Sample records for mis transistors

  1. Hafnium transistor design for neural interfacing.

    PubMed

    Parent, David W; Basham, Eric J

    2008-01-01

    A design methodology is presented that uses the EKV model and the g(m)/I(D) biasing technique to design hafnium oxide field effect transistors that are suitable for neural recording circuitry. The DC gain of a common source amplifier is correlated to the structural properties of a Field Effect Transistor (FET) and a Metal Insulator Semiconductor (MIS) capacitor. This approach allows a transistor designer to use a design flow that starts with simple and intuitive 1-D equations for gain that can be verified in 1-D MIS capacitor TCAD simulations, before final TCAD process verification of transistor properties. The DC gain of a common source amplifier is optimized by using fast 1-D simulations and using slower, complex 2-D simulations only for verification. The 1-D equations are used to show that the increased dielectric constant of hafnium oxide allows a higher DC gain for a given oxide thickness. An additional benefit is that the MIS capacitor can be employed to test additional performance parameters important to an open gate transistor such as dielectric stability and ionic penetration.

  2. Plasma Deposited SiO2 for Planar Self-Aligned Gate Metal-Insulator-Semiconductor Field Effect Transistors on Semi-Insulating InP

    NASA Technical Reports Server (NTRS)

    Tabory, Charles N.; Young, Paul G.; Smith, Edwyn D.; Alterovitz, Samuel A.

    1994-01-01

    Metal-insulator-semiconductor (MIS) field effect transistors were fabricated on InP substrates using a planar self-aligned gate process. A 700-1000 A gate insulator of Si02 doped with phosphorus was deposited by a direct plasma enhanced chemical vapor deposition at 400 mTorr, 275 C, 5 W, and power density of 8.5 MW/sq cm. High frequency capacitance-voltage measurements were taken on MIS capacitors which have been subjected to a 700 C anneal and an interface state density of lxl0(exp 11)/eV/cq cm was found. Current-voltage measurements of the capacitors show a breakdown voltage of 107 V/cm and a insulator resistivity of 10(exp 14) omega cm. Transistors were fabricated on semi-insulating InP using a standard planar self-aligned gate process in which the gate insulator was subjected to an ion implantation activation anneal of 700 C. MIS field effect transistors gave a maximum extrinsic transconductance of 23 mS/mm for a gate length of 3 microns. The drain current drift saturated at 87.5% of the initial current, while reaching to within 1% of the saturated value after only 1x10(exp 3). This is the first reported viable planar InP self-aligned gate transistor process reported to date.

  3. Hafnium transistor process design for neural interfacing.

    PubMed

    Parent, David W; Basham, Eric J

    2009-01-01

    A design methodology is presented that uses 1-D process simulations of Metal Insulator Semiconductor (MIS) structures to design the threshold voltage of hafnium oxide based transistors used for neural recording. The methodology is comprised of 1-D analytical equations for threshold voltage specification, and doping profiles, and 1-D MIS Technical Computer Aided Design (TCAD) to design a process to implement a specific threshold voltage, which minimized simulation time. The process was then verified with a 2-D process/electrical TCAD simulation. Hafnium oxide films (HfO) were grown and characterized for dielectric constant and fixed oxide charge for various annealing temperatures, two important design variables in threshold voltage design.

  4. Improved linearity in AlGaN/GaN metal-insulator-semiconductor high electron mobility transistors with nonlinear polarization dielectric

    NASA Astrophysics Data System (ADS)

    Gao, Tao; Xu, Ruimin; Kong, Yuechan; Zhou, Jianjun; Kong, Cen; Dong, Xun; Chen, Tangsheng

    2015-06-01

    We demonstrate highly improved linearity in a nonlinear ferroelectric of Pb(Zr0.52Ti0.48)-gated AlGaN/GaN metal-insulator-semiconductor high electron mobility transistor (MIS-HEMT). Distinct double-hump feature in the transconductance-gate voltage (gm-Vg) curve is observed, yielding remarkable enhancement in gate voltage swing as compared to MIS-HEMT with conventional linear gate dielectric. By incorporating the ferroelectric polarization into a self-consistent calculation, it is disclosed that in addition to the common hump corresponding to the onset of electron accumulation, the second hump at high current level is originated from the nonlinear polar nature of ferroelectric, which enhances the gate capacitance by increasing equivalent dielectric constant nonlinearly. This work paves a way for design of high linearity GaN MIS-HEMT by exploiting the nonlinear properties of dielectric.

  5. Mechanism of leakage of ion-implantation isolated AlGaN/GaN MIS-high electron mobility transistors on Si substrate

    NASA Astrophysics Data System (ADS)

    Zhang, Zhili; Song, Liang; Li, Weiyi; Fu, Kai; Yu, Guohao; Zhang, Xiaodong; Fan, Yaming; Deng, Xuguang; Li, Shuiming; Sun, Shichuang; Li, Xiajun; Yuan, Jie; Sun, Qian; Dong, Zhihua; Cai, Yong; Zhang, Baoshun

    2017-08-01

    In this paper, we systematically investigated the leakage mechanism of the ion-implantation isolated AlGaN/GaN metal-insulator-semiconductor high electron mobility transistors (MIS-HEMTs) on Si substrate. By means of combined DC tests at different temperatures and electric field dependence, we demonstrated the following original results: (1) It is proved that gate leakage is the main contribution to OFF-state leakage of ion-implantation isolated AlGaN/GaN MIS-HEMTs, and the gate leakage path is a series connection of the gate dielectric Si3N4 and Si3N4-GaN interface. (2) The dominant mechanisms of the leakage current through LPCVD-Si3N4 gate dielectric and Si3N4-GaN interface are identified to be Frenkel-Poole emission and two-dimensional variable range hopping (2D-VRH), respectively. (3) A certain temperature annealing could reduce the density of the interface state that produced by ion implantation, and consequently suppress the interface leakage transport, which results in a decrease in OFF-state leakage current of ion-implantation isolated AlGaN/GaN MIS-HEMTs.

  6. Improved linearity in AlGaN/GaN metal-insulator-semiconductor high electron mobility transistors with nonlinear polarization dielectric

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Gao, Tao; Science and Technology on Monolithic Integrated Circuits and Modules Laboratory, Nanjing Electronic Devices Institute, Nanjing 210016; Xu, Ruimin

    2015-06-15

    We demonstrate highly improved linearity in a nonlinear ferroelectric of Pb(Zr{sub 0.52}Ti{sub 0.48})-gated AlGaN/GaN metal-insulator-semiconductor high electron mobility transistor (MIS-HEMT). Distinct double-hump feature in the transconductance-gate voltage (g{sub m}-V{sub g}) curve is observed, yielding remarkable enhancement in gate voltage swing as compared to MIS-HEMT with conventional linear gate dielectric. By incorporating the ferroelectric polarization into a self-consistent calculation, it is disclosed that in addition to the common hump corresponding to the onset of electron accumulation, the second hump at high current level is originated from the nonlinear polar nature of ferroelectric, which enhances the gate capacitance by increasing equivalent dielectricmore » constant nonlinearly. This work paves a way for design of high linearity GaN MIS-HEMT by exploiting the nonlinear properties of dielectric.« less

  7. Comparative study on nitridation and oxidation plasma interface treatment for AlGaN/GaN MIS-HEMTs with AlN gate dielectric

    NASA Astrophysics Data System (ADS)

    Zhu, Jie-Jie; Ma, Xiao-Hua; Hou, Bin; Chen, Li-Xiang; Zhu, Qing; Hao, Yue

    2017-02-01

    This paper demonstrated the comparative study on interface engineering of AlN/AlGaN/GaN metal-insulator-semiconductor high-electron-mobility transistors (MIS-HEMTs) by using plasma interface pre-treatment in various ambient gases. The 15 nm AlN gate dielectric grown by plasma-enhanced atomic layer deposition significantly suppressed the gate leakage current by about two orders of magnitude and increased the peak field-effect mobility by more than 50%. NH3/N2 nitridation plasma treatment (NPT) was used to remove the 3 nm poor-quality interfacial oxide layer and N2O/N2 oxidation plasma treatment (OPT) to improve the quality of interfacial layer, both resulting in improved dielectric/barrier interface quality, positive threshold voltage (V th) shift larger than 0.9 V, and negligible dispersion. In comparison, however, NPT led to further decrease in interface charges by 3.38 × 1012 cm-2 and an extra positive V th shift of 1.3 V. Analysis with fat field-effect transistors showed that NPT resulted in better sub-threshold characteristics and transconductance linearity for MIS-HEMTs compared with OPT. The comparative study suggested that direct removing the poor interfacial oxide layer by nitridation plasma was superior to improving the quality of interfacial layer by oxidation plasma for the interface engineering of GaN-based MIS-HEMTs.

  8. T-gate geometric (solution for submicrometer gate length) HEMT: Physical analysis, modeling and implementation as parasitic elements and its usage as dual gate for variable gain amplifiers

    NASA Astrophysics Data System (ADS)

    Gupta, Ritesh; Rathi, Servin; Kaur, Ravneet; Gupta, Mridula; Gupta, R. S.

    2009-03-01

    In order to achieve superior RF performance, short gate length is required for the compound semiconductor field effect transistors, but the limitation in lithography for submicrometer gate lengths leads to the formation of various metal-insulator geometries like T-gate [Sandeep R. Bahl, Jesus A. del Alamo, Physics of breakdown in InAlAs/ n +-InGaAs heterostructure field-effect transistors, IEEE Trans. Electron Devices 41 (12) (1994) 2268-2275]. These geometries are the combination of various Metal-Semiconductor (MS)/Metal-Air-Semiconductor (MAS) contacts. Moreover, field plates [S. Karmalkar, M.S. Shur, G. Simin, M. Asif Khan, Field-plate engineering for HFETs, IEEE Trans. Electron Devices 52 (2005) 2534-2540] are also being fabricated these days, mainly at the drain end ( Γ-gate) having Metal-Insulator-Semiconductor (MIS) instead of MAS contact with the intention of increasing the breakdown voltage of the device. To realize the effect of upper gate electrode in the T-gate structure and field plates, an analytical model has been proposed in the present article by dividing the whole structure into MS/MIS contact regions, applying current continuity among them and solving iteratively. The model proposed for Metal-Insulator Semiconductor High Electron Mobility Transistor (MISHEMT) [R. Gupta, S.K. Aggarwal, M. Gupta, R.S. Gupta, Analytical model for metal insulator semiconductor high electron mobility transistor (MISHEMT) for its high frequency and high power applications, J. Semicond. Technol. Sci. 6 (3) (2006) 189-198], is equally applicable to High Electron Mobility Transistors (HEMT) and has been used to formulate this model. In this paper, various structures and geometries have been compared to anticipate the need of T-gate modeling. The effect of MIS contacts has been implemented as parasitic resistance and capacitance and has also been studied to control the middle conventional gate as in dual gate technology by applying separate voltages across it. The results obtained using the proposed analytical scheme has been compared with simulated and experimental results, to prove the validity of our model.

  9. Electrical properties of GaN-based metal-insulator-semiconductor structures with Al2O3 deposited by atomic layer deposition using water and ozone as the oxygen precursors

    NASA Astrophysics Data System (ADS)

    Kubo, Toshiharu; Freedsman, Joseph J.; Iwata, Yasuhiro; Egawa, Takashi

    2014-04-01

    Al2O3 deposited by atomic layer deposition (ALD) was used as an insulator in metal-insulator-semiconductor (MIS) structures for GaN-based MIS-devices. As the oxygen precursors for the ALD process, water (H2O), ozone (O3), and both H2O and O3 were used. The chemical characteristics of the ALD-Al2O3 surfaces were investigated by x-ray photoelectron spectroscopy. After fabrication of MIS-diodes and MIS-high-electron-mobility transistors (MIS-HEMTs) with the ALD-Al2O3, their electrical properties were evaluated by current-voltage (I-V) and capacitance-voltage (C-V) measurements. The threshold voltage of the C-V curves for MIS-diodes indicated that the fixed charge in the Al2O3 layer is decreased when using both H2O and O3 as the oxygen precursors. Furthermore, MIS-HEMTs with the H2O + O3-based Al2O3 showed good dc I-V characteristics without post-deposition annealing of the ALD-Al2O3, and the drain leakage current in the off-state region was suppressed by seven orders of magnitude.

  10. A mixed solution-processed gate dielectric for zinc-tin oxide thin-film transistor and its MIS capacitance

    NASA Astrophysics Data System (ADS)

    Kim, Hunho; Kwack, Young-Jin; Yun, Eui-Jung; Choi, Woon-Seop

    2016-09-01

    Solution-processed gate dielectrics were fabricated with the combined ZrO2 and Al2O3 (ZAO) in the form of mixed and stacked types for oxide thin film transistors (TFTs). ZAO thin films prepared with double coatings for solid gate dielectrics were characterized by analytical tools. For the first time, the capacitance of the oxide semiconductor was extracted from the capacitance-voltage properties of the zinc-tin oxide (ZTO) TFTs with the combined ZAO dielectrics by using the proposed metal-insulator-semiconductor (MIS) structure model. The capacitance evolution of the semiconductor from the TFT model structure described well the threshold voltage shift observed in the ZTO TFT with the ZAO (1:2) gate dielectric. The electrical properties of the ZTO TFT with a ZAO (1:2) gate dielectric showed low voltage driving with a field effect mobility of 37.01 cm2/Vs, a threshold voltage of 2.00 V, an on-to-off current ratio of 1.46 × 105, and a subthreshold slope of 0.10 V/dec.

  11. A mixed solution-processed gate dielectric for zinc-tin oxide thin-film transistor and its MIS capacitance

    PubMed Central

    Kim, Hunho; Kwack, Young-Jin; Yun, Eui-Jung; Choi, Woon-Seop

    2016-01-01

    Solution-processed gate dielectrics were fabricated with the combined ZrO2 and Al2O3 (ZAO) in the form of mixed and stacked types for oxide thin film transistors (TFTs). ZAO thin films prepared with double coatings for solid gate dielectrics were characterized by analytical tools. For the first time, the capacitance of the oxide semiconductor was extracted from the capacitance-voltage properties of the zinc-tin oxide (ZTO) TFTs with the combined ZAO dielectrics by using the proposed metal-insulator-semiconductor (MIS) structure model. The capacitance evolution of the semiconductor from the TFT model structure described well the threshold voltage shift observed in the ZTO TFT with the ZAO (1:2) gate dielectric. The electrical properties of the ZTO TFT with a ZAO (1:2) gate dielectric showed low voltage driving with a field effect mobility of 37.01 cm2/Vs, a threshold voltage of 2.00 V, an on-to-off current ratio of 1.46 × 105, and a subthreshold slope of 0.10 V/dec. PMID:27641430

  12. Efficient III-Nitride MIS-HEMT devices with high-κ gate dielectric for high-power switching boost converter circuits

    NASA Astrophysics Data System (ADS)

    Mohanbabu, A.; Mohankumar, N.; Godwin Raj, D.; Sarkar, Partha; Saha, Samar K.

    2017-03-01

    The paper reports the results of a systematic theoretical study on efficient recessed-gate, double-heterostructure, and normally-OFF metal-insulator-semiconductor high-electron mobility transistors (MIS-HEMTs), HfAlOx/AlGaN on Al2O3 substrate. In device architecture, a thin AlGaN layer is used in the AlGaN graded barrier MIS-HEMTs that offers an excellent enhancement-mode device operation with threshold voltage higher than 5.3 V and drain current above 0.64 A/mm along with high on-current/off-current ratio over 107 and subthreshold slope less than 73 mV/dec. In addition, a high OFF-state breakdown voltage of 1200 V is achieved for a device with a gate-to-drain distance and field-plate length of 15 μm and 5.3 μm, respectively at a drain current of 1 mA/mm with a zero gate bias, and the substrate grounded. The numerical device simulation results show that in comparison to a conventional AlGaN/GaN MIS-HEMT of similar design, a graded barrier MIS-HEMT device exhibits a better interface property, remarkable suppression of leakage current, and a significant improvement of breakdown voltage for HfAlOx gate dielectric. Finally, the benefit of HfAlOx graded-barrier AlGaN MIS-HEMTs based switching devices is evaluated on an ultra-low-loss converter circuit.

  13. Integrated Microfluidic Membrane Transistor Utilizing Chemical Information for On-Chip Flow Control.

    PubMed

    Frank, Philipp; Schreiter, Joerg; Haefner, Sebastian; Paschew, Georgi; Voigt, Andreas; Richter, Andreas

    2016-01-01

    Microfluidics is a great enabling technology for biology, biotechnology, chemistry and general life sciences. Despite many promising predictions of its progress, microfluidics has not reached its full potential yet. To unleash this potential, we propose the use of intrinsically active hydrogels, which work as sensors and actuators at the same time, in microfluidic channel networks. These materials transfer a chemical input signal such as a substance concentration into a mechanical output. This way chemical information is processed and analyzed on the spot without the need for an external control unit. Inspired by the development electronics, our approach focuses on the development of single transistor-like components, which have the potential to be used in an integrated circuit technology. Here, we present membrane isolated chemical volume phase transition transistor (MIS-CVPT). The device is characterized in terms of the flow rate from source to drain, depending on the chemical concentration in the control channel, the source-drain pressure drop and the operating temperature.

  14. Integrated Microfluidic Membrane Transistor Utilizing Chemical Information for On-Chip Flow Control

    PubMed Central

    Frank, Philipp; Schreiter, Joerg; Haefner, Sebastian; Paschew, Georgi; Voigt, Andreas; Richter, Andreas

    2016-01-01

    Microfluidics is a great enabling technology for biology, biotechnology, chemistry and general life sciences. Despite many promising predictions of its progress, microfluidics has not reached its full potential yet. To unleash this potential, we propose the use of intrinsically active hydrogels, which work as sensors and actuators at the same time, in microfluidic channel networks. These materials transfer a chemical input signal such as a substance concentration into a mechanical output. This way chemical information is processed and analyzed on the spot without the need for an external control unit. Inspired by the development electronics, our approach focuses on the development of single transistor-like components, which have the potential to be used in an integrated circuit technology. Here, we present membrane isolated chemical volume phase transition transistor (MIS-CVPT). The device is characterized in terms of the flow rate from source to drain, depending on the chemical concentration in the control channel, the source-drain pressure drop and the operating temperature. PMID:27571209

  15. Low-frequency noise in AlN/AlGaN/GaN metal-insulator-semiconductor devices: A comparison with Schottky devices

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Le, Son Phuong; Nguyen, Tuan Quy; Shih, Hong-An

    2014-08-07

    We have systematically investigated low-frequency noise (LFN) in AlN/AlGaN/GaN metal-insulator-semiconductor (MIS) devices, where the AlN gate insulator layer was sputtering-deposited on the AlGaN surface, in comparison with LFN in AlGaN/GaN Schottky devices. By measuring LFN in ungated two-terminal devices and heterojunction field-effect transistors (HFETs), we extracted LFN characteristics in the intrinsic gated region of the HFETs. Although there is a bias regime of the Schottky-HFETs in which LFN is dominated by the gate leakage current, LFN in the MIS-HFETs is always dominated by only the channel current. Analyzing the channel-current-dominated LFN, we obtained Hooge parameters α for the gated regionmore » as a function of the sheet electron concentration n{sub s} under the gate. In a regime of small n{sub s}, both the MIS- and Schottky-HFETs exhibit α∝n{sub s}{sup −1}. On the other hand, in a middle n{sub s} regime of the MIS-HFETs, α decreases rapidly like n{sub s}{sup −ξ} with ξ ∼ 2-3, which is not observed for the Schottky-HFETs. In addition, we observe strong increase in α∝n{sub s}{sup 3} in a large n{sub s} regime for both the MIS- and Schottky-HFETs.« less

  16. Thickness engineering of atomic layer deposited Al2O3 films to suppress interfacial reaction and diffusion of Ni/Au gate metal in AlGaN/GaN HEMTs up to 600 °C in air

    NASA Astrophysics Data System (ADS)

    Suria, Ateeq J.; Yalamarthy, Ananth Saran; Heuser, Thomas A.; Bruefach, Alexandra; Chapin, Caitlin A.; So, Hongyun; Senesky, Debbie G.

    2017-06-01

    In this paper, we describe the use of 50 nm atomic layer deposited (ALD) Al2O3 to suppress the interfacial reaction and inter-diffusion between the gate metal and semiconductor interface, to extend the operation limit up to 600 °C in air. Suppression of diffusion is verified through Auger electron spectroscopy (AES) depth profiling and X-ray diffraction (XRD) and is further supported with electrical characterization. An ALD Al2O3 thin film (10 nm and 50 nm), which functions as a dielectric layer, was inserted between the gate metal (Ni/Au) and heterostructure-based semiconductor material (AlGaN/GaN) to form a metal-insulator-semiconductor high electron mobility transistor (MIS-HEMT). This extended the 50 nm ALD Al2O3 MIS-HEMT (50-MIS) current-voltage (Ids-Vds) and gate leakage (Ig,leakage) characteristics up to 600 °C. Both, the 10 nm ALD Al2O3 MIS-HEMT (10-MIS) and HEMT, failed above 350 °C, as evidenced by a sudden increase of approximately 50 times and 5.3 × 106 times in Ig,leakage, respectively. AES on the HEMT revealed the formation of a Ni-Au alloy and Ni present in the active region. Additionally, XRD showed existence of metal gallides in the HEMT. The 50-MIS enables the operation of AlGaN/GaN based electronics in oxidizing high-temperature environments, by suppressing interfacial reaction and inter-diffusion of the gate metal with the semiconductor.

  17. Rapid thermal anneal in InP, GaAs and GaAs/GaAlAs

    NASA Astrophysics Data System (ADS)

    Descouts, B.; Duhamel, N.; Godefroy, S.; Krauz, P.

    Ion implantation in semiconductors provides a doping technique with several advantages over more conventional doping methods and is now extensively used for device applications, e.g. field effect transistors (MESFET GaAs, MIS (InP), GaAs/GaAlAs heterojunction bipolar transistors (HBT). Because of the lattice disorder produced by the implantation, the dopant must be made electrically active by a postimplant anneal. As the device performances are very dependent on its electrical characteristics, the anneal is a very important stage of the process. Rapid anneal is known to provide less exodiffusion and less induffusion of impurities compared to conventional furnace anneal, so this technique has been used in this work to activate an n-type dopant (Si) in InP and a p-type dopant (Mg) in GaAs and GaAs/GaAIAs. These two ions have been chosen to realize implanted MIS InP and the base contacts for GaAs/GaAlAs HBTs. The experimental conditions to obtain the maximum electrical activity in these two cases will be detailed. For example, although we have not been able to obtain a flat profile in Mg + implanted GaAs/GaAlAs heterostructure by conventional thermal anneal, rapid thermal anneal gives a flat hole profile over a depth of 0.5 μm with a concentration of 1 x 10 19 cm -3.

  18. Capacitance-voltage analysis of electrical properties for WSe2 field effect transistors with high-k encapsulation layer

    NASA Astrophysics Data System (ADS)

    Ko, Seung-Pil; Shin, Jong Mok; Jang, Ho Kyun; You, Min Youl; Jin, Jun-Eon; Choi, Miri; Cho, Jiung; Kim, Gyu-Tae

    2018-02-01

    Doping effects in devices based on two-dimensional (2D) materials have been widely studied. However, detailed analysis and the mechanism of the doping effect caused by encapsulation layers has not been sufficiently explored. In this work, we present experimental studies on the n-doping effect in WSe2 field effect transistors (FETs) with a high-k encapsulation layer (Al2O3) grown by atomic layer deposition. In addition, we demonstrate the mechanism and origin of the doping effect. After encapsulation of the Al2O3 layer, the threshold voltage of the WSe2 FET negatively shifted with the increase of the on-current. The capacitance-voltage measurements of the metal insulator semiconductor (MIS) structure proved the presence of the positive fixed charges within the Al2O3 layer. The flat-band voltage of the MIS structure of Au/Al2O3/SiO2/Si was shifted toward the negative direction on account of the positive fixed charges in the Al2O3 layer. Our results clearly revealed that the fixed charges in the Al2O3 encapsulation layer modulated the Fermi energy level via the field effect. Moreover, these results possibly provide fundamental ideas and guidelines to design 2D materials FETs with high-performance and reliability.

  19. Noise characterization of enhancement-mode AlGaN graded barrier MIS-HEMT devices

    NASA Astrophysics Data System (ADS)

    Mohanbabu, A.; Saravana Kumar, R.; Mohankumar, N.

    2017-12-01

    This paper reports a systematic theoretical study on the microwave noise performance of graded AlGaN/GaN metal-insulator semiconductor high-electron mobility transistors (MIS-HEMTs) built on an Al2O3 substrate. The HfAlOx/AlGaN/GaN MIS-HEMT devices designed for this study show an outstanding small signal analog/RF and noise performance. The results on 1 μm gate length device show an enhancement mode operation with threshold voltage, VT = + 5.3 V, low drain leakage current, Ids,LL in the order of 1 × 10-9 A/mm along with high current gain cut-off frequency, fT of 17 GHz and maximum oscillation frequency fmax of 47 GHz at Vds = 10 V. The device Isbnd V and low-frequency noise estimation of the gate and drain noise spectral density and their correlation are evaluated using a Green's function method under different biasing conditions. The devices show a minimum noise figure (NFmin) of 1.053 dB in combination with equivalent noise resistance (Rn) of 23 Ω at 17 GHz, at Vgs = 6 V and Vds = 5 V which is relatively low and is suitable for broad-band low-noise amplifiers. This study shows that the graded AlGaN MIS-HEMT with HfAlOX gate insulator is appropriate for application requiring high-power and low-noise.

  20. Interface Si donor control to improve dynamic performance of AlGaN/GaN MIS-HEMTs

    NASA Astrophysics Data System (ADS)

    Song, Liang; Fu, Kai; Zhang, Zhili; Sun, Shichuang; Li, Weiyi; Yu, Guohao; Hao, Ronghui; Fan, Yaming; Shi, Wenhua; Cai, Yong; Zhang, Baoshun

    2017-12-01

    In this letter, we have studied the performance of AlGaN/GaN metal-insulator-semiconductor high electron mobility transistors (MIS-HEMTs) with different interface Si donor incorporation which is tuned during the deposition process of LPCVD-SiNx which is adopted as gate dielectric and passivation layer. Current collapse of the MIS-HEMTs without field plate is suppressed more effectively by increasing the SiH2Cl2/NH3 flow ratio and the normalized dynamic on-resistance (RON) is reduced two orders magnitude after off-state VDS stress of 600 V for 10 ms. Through interface characterization, we have found that the interface deep-level traps distribution with high Si donor incorporation by increasing the SiH2Cl2/NH3 flow ratio is lowered. It's indicated that the Si donors are most likely to fill and screen the deep-level traps at the interface resulting in the suppression of slow trapping process and the virtual gate effect. Although the Si donor incorporation brings about the increase of gate leakage current (IGS), no clear degradation of breakdown voltage can be seen by choosing appropriate SiH2Cl2/NH3 flow ratio.

  1. Schottky Barrier Height Engineering for Electrical Contacts of Multilayered MoS2 Transistors with Reduction of Metal-Induced Gap States.

    PubMed

    Kim, Gwang-Sik; Kim, Seung-Hwan; Park, June; Han, Kyu Hyun; Kim, Jiyoung; Yu, Hyun-Yong

    2018-06-06

    The difficulty in Schottky barrier height (SBH) control arising from Fermi-level pinning (FLP) at electrical contacts is a bottleneck in designing high-performance nanoscale electronics and optoelectronics based on molybdenum disulfide (MoS 2 ). For electrical contacts of multilayered MoS 2 , the Fermi level on the metal side is strongly pinned near the conduction-band edge of MoS 2 , which makes most MoS 2 -channel field-effect transistors (MoS 2 FETs) exhibit n-type transfer characteristics regardless of their source/drain (S/D) contact metals. In this work, SBH engineering is conducted to control the SBH of electrical top contacts of multilayered MoS 2 by introducing a metal-interlayer-semiconductor (MIS) structure which induces the Fermi-level unpinning by a reduction of metal-induced gap states (MIGS). An ultrathin titanium dioxide (TiO 2 ) interlayer is inserted between the metal contact and the multilayered MoS 2 to alleviate FLP and tune the SBH at the S/D contacts of multilayered MoS 2 FETs. A significant alleviation of FLP is demonstrated as MIS structures with 1 nm thick TiO 2 interlayers are introduced into the S/D contacts. Consequently, the pinning factor ( S) increases from 0.02 for metal-semiconductor (MS) contacts to 0.24 for MIS contacts, and the controllable SBH range is widened from 37 meV (50-87 meV) to 344 meV (107-451 meV). Furthermore, the Fermi-level unpinning effect is reinforced as the interlayer becomes thicker. This work widens the scope for modifying electrical characteristics of contacts by providing a platform to control the SBH through a simple process as well as understanding of the FLP at the electrical top contacts of multilayered MoS 2 .

  2. Highly uniform and reliable resistive switching characteristics of a Ni/WOx/p+-Si memory device

    NASA Astrophysics Data System (ADS)

    Kim, Tae-Hyeon; Kim, Sungjun; Kim, Hyungjin; Kim, Min-Hwi; Bang, Suhyun; Cho, Seongjae; Park, Byung-Gook

    2018-02-01

    In this paper, we investigate the resistive switching behavior of a bipolar resistive random-access memory (RRAM) in a Ni/WOx/p+-Si RRAM with CMOS compatibility. Highly unifrom and reliable bipolar resistive switching characteristics are observed by a DC voltage sweeping and its switching mechanism can be explained by SCLC model. As a result, the possibility of metal-insulator-silicon (MIS) structural WOx-based RRAM's application to Si-based 1D (diode)-1R (RRAM) or 1T (transistor)-1R (RRAM) structure is demonstrated.

  3. Electrical characteristics and interface properties of ALD-HfO2/AlGaN/GaN MIS-HEMTs fabricated with post-deposition annealing

    NASA Astrophysics Data System (ADS)

    Kubo, Toshiharu; Egawa, Takashi

    2017-12-01

    HfO2/AlGaN/GaN metal-insulator-semiconductor (MIS)-type high electron mobility transistors (HEMTs) on Si substrates were fabricated by atomic layer deposition of HfO2 layers and post-deposition annealing (PDA). The current-voltage characteristics of the MIS-HEMTs with as-deposited HfO2 layers showed a low gate leakage current (I g) despite the relatively low band gap of HfO2, and a dynamic threshold voltage shift (ΔV th) was observed. After PDA above 500 °C, ΔV th was reduced from 2.9 to 0.7 V with an increase in I g from 2.2 × 10-7 to 4.8 × 10-2 mA mm-1. Effects of the PDA on the HfO2 layer and the HfO2/AlGaN interface were investigated by x-ray photoelectron spectroscopy (XPS) using synchrotron radiation. XPS data showed that oxygen vacancies exist in the as-deposited HfO2 layers and they disappeared with an increase in the PDA temperature. These results indicate that the deep electron traps that cause ΔV th are related to the oxygen vacancies in the HfO2 layers.

  4. Drain current enhancement induced by hole injection from gate of 600-V-class normally off gate injection transistor under high temperature conditions up to 200 °C

    NASA Astrophysics Data System (ADS)

    Ishii, Hajime; Ueno, Hiroaki; Ueda, Tetsuzo; Endoh, Tetsuo

    2018-06-01

    In this paper, the current–voltage (I–V) characteristics of a 600-V-class normally off GaN gate injection transistor (GIT) from 25 to 200 °C are analyzed, and it is revealed that the drain current of the GIT increases during high-temperature operation. It is found that the maximum drain current (I dmax) of the GIT is 86% higher than that of a conventional 600-V-class normally off GaN metal insulator semiconductor hetero-FET (MIS-HFET) at 150 °C, whereas the GIT obtains 56% I dmax even at 200 °C. Moreover, the mechanism of the drain current increase of the GIT is clarified by examining the relationship between the temperature dependence of the I–V characteristics of the GIT and the gate hole injection effect determined from the shift of the second transconductance (g m) peak of the g m–V g characteristic. From the above, the GIT is a promising device with enough drivability for future power switching applications even under high-temperature conditions.

  5. Unstable behaviour of normally-off GaN E-HEMT under short-circuit

    NASA Astrophysics Data System (ADS)

    Martínez, P. J.; Maset, E.; Sanchis-Kilders, E.; Esteve, V.; Jordán, J.; Bta Ejea, J.; Ferreres, A.

    2018-04-01

    The short-circuit capability of power switching devices plays an important role in fault detection and the protection of power circuits. In this work, an experimental study on the short-circuit (SC) capability of commercial 600 V Gallium Nitride enhancement-mode high-electron-mobility transistors (E-HEMT) is presented. A different failure mechanism has been identified for commercial p-doped GaN gate (p-GaN) HEMT and metal-insulator-semiconductor (MIS) HEMT. In addition to the well known thermal breakdown, a premature breakdown is shown on both GaN HEMTs, triggered by hot electron trapping at the surface, which demonstrates that current commercial GaN HEMTs has requirements for improving their SC ruggedness.

  6. Design and simulation of a novel E-mode GaN MIS-HEMT based on a cascode connection for suppression of electric field under gate and improvement of reliability

    NASA Astrophysics Data System (ADS)

    Li, Weiyi; Zhang, Zhili; Fu, Kai; Yu, Guohao; Zhang, Xiaodong; Sun, Shichuang; Song, Liang; Hao, Ronghui; Fan, Yaming; Cai, Yong; Zhang, Baoshun

    2017-07-01

    We proposed a novel AlGaN/GaN enhancement-mode (E-mode) high electron mobility transistor (HEMT) with a dual-gate structure and carried out the detailed numerical simulation of device operation using Silvaco Atlas. The dual-gate device is based on a cascode connection of an E-mode and a D-mode gate. The simulation results show that electric field under the gate is decreased by more than 70% compared to that of the conventional E-mode MIS-HEMTs (from 2.83 MV/cm decreased to 0.83 MV/cm). Thus, with the discussion of ionized trap density, the proposed dual-gate structure can highly improve electric field-related reliability, such as, threshold voltage stability. In addition, compared with HEMT with field plate structure, the proposed structure exhibits a simplified fabrication process and a more effective suppression of high electric field. Project supported by the Key Technologies Support Program of Jiangsu Province (No. BE2013002-2) and the National Key Scientific Instrument and Equipment Development Projects of China (No. 2013YQ470767).

  7. Origin of positive fixed charge at insulator/AlGaN interfaces and its control by AlGaN composition

    NASA Astrophysics Data System (ADS)

    Matys, M.; Stoklas, R.; Blaho, M.; Adamowicz, B.

    2017-06-01

    The key feature for the precise tuning of Vth in GaN-based metal-insulator-semiconductor (MIS) high electron mobility transistors is the control of the positive fixed charge (Qf) at the insulator/III-N interfaces, whose amount is often comparable to the negative surface polarization charge ( Qp o l -). In order to clarify the origin of Qf, we carried out a comprehensive capacitance-voltage (C-V) characterization of SiO2/AlxGa1-xN/GaN and SiN/AlxGa1-xN/GaN structures with Al composition (x) varying from 0.15 to 0.4. For both types of structures, we observed a significant Vth shift in C-V curves towards the positive gate voltage with increasing x. On the contrary, the Schottky gate structures exhibited Vth shift towards the more negative biases. From the numerical simulations of C-V curves using the Poisson's equation supported by the analytical calculations of Vth, we showed that the Vth shift in the examined MIS structures is due to a significant decrease in the positive Qf with rising x. Finally, we examined this result with respect to various hypotheses developed in the literature to explain the origin of the positive Qf at insulator/III-N interfaces.

  8. Properties of TiO2 thin films and a study of the TiO2-GaAs interface

    NASA Technical Reports Server (NTRS)

    Chen, C. Y.; Littlejohn, M. A.

    1977-01-01

    Titanium dioxide (TiO2) films prepared by chemical vapor deposition were investigated in this study for the purpose of the application in the GaAs metal-insulator-semiconductor field-effect transistor. The degree of crystallization increases with the deposition temperature. The current-voltage study, utilizing an Al-TiO2-Al MIM structure, reveals that the d-c conduction through the TiO2 film is dominated by the bulk-limited Poole-Frenkel emission mechanism. The dependence of the resistivity of the TiO2 films on the deposition environment is also shown. The results of the capacitance-voltage study indicate that an inversion layer in an n-type substrate can be achieved in the MIS capacitor if the TiO2 films are deposited at a temperature higher than 275 C. A process of low temperature deposition followed by the pattern definition and a higher temperature annealing is suggested for device fabrications. A model, based on the assumption that the surface state densities are continuously distributed in energy within the forbidden band gap, is proposed to interpret the lack of an inversion layer in the Al-TiO2-GaAs MIS structure with the TiO2 films deposited at 200 C.

  9. Charge injection in solution-processed organic field-effect transistors: physics, models and characterization methods.

    PubMed

    Natali, Dario; Caironi, Mario

    2012-03-15

    A high-mobility organic semiconductor employed as the active material in a field-effect transistor does not guarantee per se that expectations of high performance are fulfilled. This is even truer if a downscaled, short channel is adopted. Only if contacts are able to provide the device with as much charge as it needs, with a negligible voltage drop across them, then high expectations can turn into high performances. It is a fact that this is not always the case in the field of organic electronics. In this review, we aim to offer a comprehensive overview on the subject of current injection in organic thin film transistors: physical principles concerning energy level (mis)alignment at interfaces, models describing charge injection, technologies for interface tuning, and techniques for characterizing devices. Finally, a survey of the most recent accomplishments in the field is given. Principles are described in general, but the technologies and survey emphasis is on solution processed transistors, because it is our opinion that scalable, roll-to-roll printing processing is one, if not the brightest, possible scenario for the future of organic electronics. With the exception of electrolyte-gated organic transistors, where impressively low width normalized resistances were reported (in the range of 10 Ω·cm), to date the lowest values reported for devices where the semiconductor is solution-processed and where the most common architectures are adopted, are ∼10 kΩ·cm for transistors with a field effect mobility in the 0.1-1 cm(2)/Vs range. Although these values represent the best case, they still pose a severe limitation for downscaling the channel lengths below a few micrometers, necessary for increasing the device switching speed. Moreover, techniques to lower contact resistances have been often developed on a case-by-case basis, depending on the materials, architecture and processing techniques. The lack of a standard strategy has hampered the progress of the field for a long time. Only recently, as the understanding of the rather complex physical processes at the metal/semiconductor interfaces has improved, more general approaches, with a validity that extends to several materials, are being proposed and successfully tested in the literature. Only a combined scientific and technological effort, on the one side to fully understand contact phenomena and on the other to completely master the tailoring of interfaces, will enable the development of advanced organic electronics applications and their widespread adoption in low-cost, large-area printed circuits. Copyright © 2012 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  10. Limitations of threshold voltage engineering of AlGaN/GaN heterostructures by dielectric interface charge density and manipulation by oxygen plasma surface treatments

    NASA Astrophysics Data System (ADS)

    Lükens, G.; Yacoub, H.; Kalisch, H.; Vescan, A.

    2016-05-01

    The interface charge density between the gate dielectric and an AlGaN/GaN heterostructure has a significant impact on the absolute value and stability of the threshold voltage Vth of metal-insulator-semiconductor (MIS) heterostructure field effect transistor. It is shown that a dry-etching step (as typically necessary for normally off devices engineered by gate-recessing) before the Al2O3 gate dielectric deposition introduces a high positive interface charge density. Its origin is most likely donor-type trap states shifting Vth to large negative values, which is detrimental for normally off devices. We investigate the influence of oxygen plasma annealing techniques of the dry-etched AlGaN/GaN surface by capacitance-voltage measurements and demonstrate that the positive interface charge density can be effectively compensated. Furthermore, only a low Vth hysteresis is observable making this approach suitable for threshold voltage engineering. Analysis of the electrostatics in the investigated MIS structures reveals that the maximum Vth shift to positive voltages achievable is fundamentally limited by the onset of accumulation of holes at the dielectric/barrier interface. In the case of the Al2O3/Al0.26Ga0.74N/GaN material system, this maximum threshold voltage shift is limited to 2.3 V.

  11. Effects of surface plasma treatment on threshold voltage hysteresis and instability in metal-insulator-semiconductor (MIS) AlGaN/GaN heterostructure HEMTs

    NASA Astrophysics Data System (ADS)

    Zaidi, Z. H.; Lee, K. B.; Roberts, J. W.; Guiney, I.; Qian, H.; Jiang, S.; Cheong, J. S.; Li, P.; Wallis, D. J.; Humphreys, C. J.; Chalker, P. R.; Houston, P. A.

    2018-05-01

    In a bid to understand the commonly observed hysteresis in the threshold voltage (VTH) in AlGaN/GaN metal-insulator-semiconductor high electron mobility transistors during forward gate bias stress, we have analyzed a series of measurements on devices with no surface treatment and with two different plasma treatments before the in-situ Al2O3 deposition. The observed changes between samples were quasi-equilibrium VTH, forward bias related VTH hysteresis, and electrical response to reverse bias stress. To explain these effects, a disorder induced gap state model, combined with a discrete level donor, at the dielectric/semiconductor interface was employed. Technology Computer-Aided Design modeling demonstrated the possible differences in the interface state distributions that could give a consistent explanation for the observations.

  12. Thin film memory matrix using amorphous and high resistive layers

    NASA Technical Reports Server (NTRS)

    Thakoor, Anilkumar P. (Inventor); Lambe, John (Inventor); Moopen, Alexander (Inventor)

    1989-01-01

    Memory cells in a matrix are provided by a thin film of amorphous semiconductor material overlayed by a thin film of resistive material. An array of parallel conductors on one side perpendicular to an array of parallel conductors on the other side enable the amorphous semiconductor material to be switched in addressed areas to be switched from a high resistance state to a low resistance state with a predetermined level of electrical energy applied through selected conductors, and thereafter to be read out with a lower level of electrical energy. Each cell may be fabricated in the channel of an MIS field-effect transistor with a separate common gate over each section to enable the memory matrix to be selectively blanked in sections during storing or reading out of data. This allows for time sharing of addressing circuitry for storing and reading out data in a synaptic network, which may be under control of a microprocessor.

  13. The low threshold voltage n-type silicon transistors based on a polymer/silica nanocomposite gate dielectric: The effect of annealing temperatures on their operation

    NASA Astrophysics Data System (ADS)

    Hashemi, Adeleh; Bahari, Ali; Ghasemi, Shahram

    2017-09-01

    In this work, povidone/silica nanocomposite dielectric layers were deposited on the n-type Si (100) substrates for application in n-type silicon field-effect transistors (FET). Thermogravimetric analysis (TGA) indicated that strong chemical interactions between polymer and silica nanoparticles were created. In order to examine the effect of annealing temperatures on chemical interactions and nanostructure properties, annealing process was done at 423-513 K. Atomic force microscopy (AFM) images show the very smooth surfaces with very low surface roughness (0.038-0.088 nm). The Si2p and C1s core level photoemission spectra were deconvoluted to the chemical environments of Si and C atoms respectively. The obtained results of deconvoluted X-ray photoelectron spectroscopy (XPS) spectra revealed a high percentage of silanol hydrogen bonds in the sample which was not annealed. These bonds were inversed to stronger covalence bonds (siloxan bonds) at annealing temperature of 423 K. By further addition of temperature, siloxan bonds were shifted to lower binding energy of about 1 eV and their intensity were abated at annealing temperature of 513 K. The electrical characteristics were extracted from current-Voltage (I-V) and capacitance-voltage (C-V) measurements in metal-insulator-semiconductor (MIS) structure. The all n-type Si transistors showed very low threshold voltages (-0.24 to 1 V). The formation of the strongest cross-linking at nanostructure of dielectric film annealed at 423 K caused resulted in an un-trapped path for the transport of charge carriers yielding the lowest threshold voltage (0.08 V) and the highest electron mobility (45.01 cm2/V s) for its FET. By increasing the annealing temperature (473 and 513 K) on the nanocomposite dielectric films, the values of the average surface roughness, the capacitance and the FET threshold voltage increased and the value of FET electron field-effect mobility decreased.

  14. Diamond field effect transistors with a high-dielectric constant Ta2O5 as gate material

    NASA Astrophysics Data System (ADS)

    Liu, J.-W.; Liao, M.-Y.; Imura, M.; Watanabe, E.; Oosato, H.; Koide, Y.

    2014-06-01

    A Ta2O5/Al2O3 bilayer gate oxide with a high-dielectric constant (high-k) has been successfully applied to a hydrogenated-diamond (H-diamond) metal-insulator-semiconductor field effect transistor (MISFET). The Ta2O5 layer is prepared by a sputtering-deposition (SD) technique on the Al2O3 buffer layer fabricated by an atomic layer deposition (ALD) technique. The ALD-Al2O3 plays an important role to eliminate plasma damage for the H-diamond surface during SD-Ta2O5 deposition. The dielectric constants of the SD-Ta2O5/ALD-Al2O3 bilayer and single SD-Ta2O5 are as large as 12.7 and 16.5, respectively. The k value of the single SD-Ta2O5 in this study is in good agreement with that of the SD-Ta2O5 on oxygen-terminated diamond. The capacitance-voltage characteristic suggests low interfacial trapped charge density for the SD-Ta2O5/ALD-Al2O3/H-diamond MIS diode. The MISFET with a gate length of 4 µm has a drain current maximum and an extrinsic transconductance of -97.7 mA mm-1 (normalized by gate width) and 31.0 ± 0.1 mS mm-1, respectively. The effective mobility in the H-diamond channel layer is found to be 70.1 ± 0.5 cm2 V-1 s-1.

  15. Soil carbon unlocked from MIS 5 to MIS 1 aged North Siberian permafrost: state and fate of decomposition

    NASA Astrophysics Data System (ADS)

    Schwamborn, Georg; Stapel, Janina G.; Mangelsdorff, Kai; Walz, Josefine; Knoblauch, Christian; Wetterich, Sebastian; Schirrmeister, Lutz

    2017-04-01

    At Bol'shoy Lyakhovsky, New Siberian Archipelago, multiple permafrost cores were obtained providing a Late Quaternary environmental record with deposits from marine isotope stages MIS 5 to MIS 1. This exceptionally long record is used to evaluate the stored potential of the freeze-locked organic matter (OM) to serve as substrate provider for greenhouse gas producing microorganisms. We relate modern signals of OM degradation from MIS 1 deposits to previous glacial-time deposits (MIS 4 and MIS 3) and to interglacial deposits (MIS 5), which may serve as an analogue for a future Arctic warmer than modern. From the oldest to the youngest, the composite record includes re-frozen MIS 5 lake deposits (sandy silt), floodplain deposits (sandy silt) from MIS 4, Ice Complex (i.e. Yedoma) deposits from MIS 4 to 3 (sandy silt), and alas deposits (sandy silt) from a drained and re-frozen thermokarst basin with MIS 1 ages. Whereas glacial-time deposits (MIS 4 and MIS 3) are fairly ice-rich with a median at 43 wt% ice content, interglacial deposits (MIS 5 and MIS 1) are moderately ice-rich with a median at 31 wt% ice content. In terms of total organic carbon content glacial-time deposits have moderate values with a median at 2.4 wt% and interglacial deposits have low values with a median at 0.4 wt%. Deposits from MIS 4 and MIS 3 possess an increased aliphatic character and therefore higher OM quality in terms of biodegradation compared to deposits from MIS 5 and MIS 1. The strongest primal and future substrate potential is stored within the glacial-time deposits, especially in those layers deposited during environmental conditions with increased moisture. The interstadial MIS 3 deposits hold the highest concentrations of pore-water acetate, which serve as optimal substrate for greenhouse gas generating microorganisms once it is unlocked from the perennially frozen ground. MIS 3 deposits also contain the highest concentrations of organic acids ester-bound to the organic matrix, implying an increased and still stored future substrate pool. In contrast, interglacial MIS 5 deposits are distinctly depleted in both primal and future substrate pools, whereas MIS 1 substrates are partly depleted in that sense. Incubation experiments reveal that moderate CO2 and low CH4 concentrations can be generated from the deposits (after 285 days at 4°C). MIS 4 and MIS 3 deposits produce markedly higher amounts of aerobic and anaerobic CO2 than MIS 5 deposits. CH4 production was only observed in MIS 5 and in a few MIS 1 samples. This points to the fact that greenhouse gas production potentials depend on particular soil properties and environmental conditions during OM deposition and the degree of degradation prior to incorporation into permafrost.

  16. A national review of the frequency of minimally invasive surgery among general surgery residents: assessment of ACGME case logs during 2 decades of general surgery resident training.

    PubMed

    Richards, Morgan K; McAteer, Jarod P; Drake, F Thurston; Goldin, Adam B; Khandelwal, Saurabh; Gow, Kenneth W

    2015-02-01

    Minimally invasive surgery (MIS) has created a shift in how many surgical diseases are treated. Examining the effect on resident operative experience provides valuable insight into trends that may be useful for restructuring the requirements of resident training. To evaluate changes in general surgery resident operative experience regarding MIS. Retrospective review of the frequency of MIS relative to open operations among general surgery residents using the Accreditation Council for Graduate Medical Education case logs for academic years 1993-1994 through 2011-2012. General surgery residency training among accredited programs in the United States. We analyzed the difference in the mean number of MIS techniques and corresponding open procedures across training periods using 2-tailed t tests with statistical significance set at P < .05. Of 6,467,708 operations with the option of MIS, 2,393,030 (37.0%) were performed with the MIS approach. Of all MIS operations performed, the 5 most common were cholecystectomy (48.5%), appendectomy (16.2%), groin hernia repair (10.0%), abdominal exploration (nontrauma) (4.4%), and antireflux procedures (3.6%). During the study period, there was a transition from a predominantly open to MIS approach for appendectomy, antireflux procedures, thoracic wedge resection, and partial gastric resection. Cholecystectomy is the only procedure for which MIS was more common than the open technique throughout the study period (P < .001). The open approach is more common for all other procedures, including splenectomy (0.7% MIS), common bile duct exploration (24.9% MIS), gastrostomy (25.9% MIS), abdominal exploration (33.1% MIS), hernia (20.3% MIS), lung resection (22.3% MIS), partial or total colectomy (39.1%), enterolysis (19.0% MIS), ileostomy (9.0% MIS), enterectomy (5.2% MIS), vagotomy (1.8% MIS), and pediatric antireflux procedures (35.9% MIS); P < .001. Minimally invasive surgery has an increasingly prominent role in contemporary surgical therapy for many common diseases. The open approach, however, still predominates in all but 5 procedures. Residents today must become efficient at performing multiple techniques for a single procedure, which demands a broader skill set than in the past.

  17. Intestinal microflora as potential modifiers of sensitizer activity in vivo

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Sheldon, P.W.; Clarke, C.; Dawson, K.B.

    1984-08-01

    Treatment of mice (some bearing Lewis lung tumors), with penicillin (PEN) at 500 mg/l drinking water for one week prior to treatment with misonidazole (MIS), resulted in: the elimination of their anaerobic cecal flora; a decrease in MIS-induced neurotoxicity; an increase in pharmacological exposure to MIS; a decrease in MIS chemopotentiation; a probable increase in MIS radiosensitization; an increase in MIS induced hypothermia. Assuming no chemical interaction between PEN and MIS, these observations indicate that the intestinal microflora can influence the activity of MIS in vivo. The observed reduction in the neurotoxic but not the radiosensitizing potential of MIS followingmore » PEN treatment indicates a therapeutic benefit.« less

  18. Defect Generation for a Hydrated Layer and Thermal Stability Based on Ba0.7Sr0.3TiO3/SiO2 as H+ Sensitive Layer in Ion-Sensitive Field-Effect Transistor Devices

    NASA Astrophysics Data System (ADS)

    Chen, Chun-Yuan; Chou, Jung-Chuan; Chou, Hsueh-Tao

    2009-04-01

    In this paper, we present a novel sensitive ion-sensitive field-effect transistor (ISFET) membrane based on Ba0.7Sr0.3TiO3 (BST)/SiO2 fabricated by sputtering deposition. The proposed device exhibits a linear shift in acidic solutions in the pH range from 1 to 10. The device sensitivity was about 50-55 mV/pH for different deposition times. We also examined the trapping behavior of the surface hydrated layer using the metal-insulator-semiconductor (MIS) structure. Results show that the hydration layer gives rise to stress polarity dependence of electron injection when immersed in pH buffer solutions. Injection from the gate electrode produces larger positive charges and interface state densities in contrast to the substrate injection, which causes simultaneous positive and negative charge trapping. A physical model that quantitatively describes the asymmetry associated with the hydrated diffusion layer is presented, and the temperature effects of BST/SiO2 ISFET devices in the range from 25 to 65 °C were examined. We observed that pH sensitivity increases with increasing temperature. The temperature coefficient of sensitivity (TCS) can be divided into two different ranges: 0.08 mV/pH °C between 25 and 45 °C, and 0.57 mV/pH °C between 45 and 65 °C. A better thermal stability is produced in the 25 and 45 °C range in comparison with other sensitive layers.

  19. Sensitivity of the Greenland Ice Sheet to Interglacial Climate Forcing: MIS 5e Versus MIS 11

    NASA Astrophysics Data System (ADS)

    Rachmayani, Rima; Prange, Matthias; Lunt, Daniel J.; Stone, Emma J.; Schulz, Michael

    2017-11-01

    The Greenland Ice Sheet (GrIS) is thought to have contributed substantially to high global sea levels during the interglacials of Marine Isotope Stage (MIS) 5e and 11. Geological evidence suggests that the mass loss of the GrIS was greater during the peak interglacial of MIS 11 than MIS 5e, despite a weaker boreal summer insolation. We address this conundrum by using the three-dimensional thermomechanical ice sheet model Glimmer forced by Community Climate System Model version 3 output for MIS 5e and MIS 11 interglacial time slices. Our results suggest a stronger sensitivity of the GrIS to MIS 11 climate forcing than to MIS 5e forcing. Besides stronger greenhouse gas radiative forcing, the greater MIS 11 GrIS mass loss relative to MIS 5e is attributed to a larger oceanic heat transport toward high latitudes by a stronger Atlantic meridional overturning circulation. The vigorous MIS 11 ocean overturning, in turn, is related to a stronger wind-driven salt transport from low to high latitudes promoting North Atlantic Deep Water formation. The orbital insolation forcing, which causes the ocean current anomalies, is discussed.

  20. Rational decision making in a wide scenario of different minimally invasive lumbar interbody fusion approaches and devices.

    PubMed

    Pimenta, Luiz; Tohmeh, Antoine; Jones, David; Amaral, Rodrigo; Marchi, Luis; Oliveira, Leonardo; Pittman, Bruce C; Bae, Hyun

    2018-03-01

    With the proliferation of a variety of modern MIS spine surgery procedures, it is mandatory that the surgeon dominate all aspects involved in surgical indication. The information related to the decision making in patient selection for specific procedures is mandatory for surgical success. The objective of this study is to present decision-making criteria in minimally invasive surgery (MIS) selection for a variety of patients and pathologies. In this article, practicing surgeons who specialize in various MIS approaches for spinal fusion were engaged to provide expert opinion and literature review on decision making criteria for several MIS procedures. Pros, cons, relative limitations, and case examples are provided for patient selection in treatment with MIS posterolateral fusion (MIS-PLF), mini anterior lumbar interbody fusion (mini-ALIF), lateral interbody fusion (LLIF), MIS posterior lumbar interbody fusion (MIS-PLIF) and MIS transforaminal lumbar interbody fusion (MIS-TLIF). There is a variety of aspects to consider when deciding which modern MIS surgical approach is most appropriate to use based on patient and pathologic characteristics. The surgeon must adapt them to the characteristic of each type of patients, helping them to choose the most effective and efficient therapeutic option for each case.

  1. A high-resolution mid-Pleistocene temperature record from Arctic Lake El'gygytgyn: a 50 kyr super interglacial from MIS 33 to MIS 31?

    NASA Astrophysics Data System (ADS)

    de Wet, Gregory A.; Castañeda, Isla S.; DeConto, Robert M.; Brigham-Grette, Julie

    2016-02-01

    Previous periods of extreme warmth in Earth's history are of great interest in light of current and predicted anthropogenic warming. Numerous so called "super interglacial" intervals, with summer temperatures significantly warmer than today, have been identified in the 3.6 million year (Ma) sediment record from Lake El'gygytgyn, northeast Russia. To date, however, a high-resolution paleotemperature reconstruction from any of these super interglacials is lacking. Here we present a paleotemperature reconstruction based on branched glycerol dialkyl glycerol tetraethers (brGDGTs) from Marine Isotope Stages (MIS) 35 to MIS 29, including super interglacial MIS 31. To investigate this period in detail, samples were analyzed with an unprecedented average sample resolution of 500 yrs from MIS 33 to MIS 30. Our results suggest the entire period currently defined as MIS 33-31 (∼1114-1062 kyr BP) was characterized by generally warm and highly variable conditions at the lake, at times out of phase with Northern Hemisphere summer insolation, and that cold "glacial" conditions during MIS 32 lasted only a few thousand years. Close similarities are seen with coeval records from high southern latitudes, supporting the suggestion that the interval from MIS 33 to MIS 31 was an exceptionally long interglacial (Teitler et al., 2015). Based on brGDGT temperatures from Lake El'gygytgyn (this study and unpublished results), warming in the western Arctic during MIS 31 was matched only by MIS 11 during the Pleistocene.

  2. An Investigation of Partizan Misere Games

    NASA Astrophysics Data System (ADS)

    Allen, Meghan Rose

    2010-08-01

    Combinatorial games are played under two different play conventions: normal play, where the last player to move wins, and mis play, where the last player to move loses. Combinatorial games are also classified into impartial positions and partizan positions, where a position is impartial if both players have the same available moves and partizan otherwise. Mis play games lack many of the useful calculational and theoretical properties of normal play games. Until Plambeck's indistinguishability quotient and mis monoid theory were developed in 2004, research on mis play games had stalled. This thesis investigates partizan combinatorial mis play games, by taking Plambeck's indistinguishability and mis monoid theory for impartial positions and extending it to partizan ones, as well as examining the difficulties in constructing a category of mis play games in a similar manner to Joyal's category of normal play games. This thesis succeeds in finding an infinite set of positions which each have finite mis monoid, examining conditions on positions for when * + * is equivalent to 0, finding a set of positions which have Tweedledum-Tweedledee type strategy, and the two most important results of this thesis: giving necessary and sufficient conditions on a set of positions Upsilon such that the mis monoid of Upsilon is the same as the mis monoid of * and giving a construction theorem which builds all positions ξ such that the mis monoid of ξ is the same as the mis monoid of *.

  3. Kinematic design considerations for minimally invasive surgical robots: an overview.

    PubMed

    Kuo, Chin-Hsing; Dai, Jian S; Dasgupta, Prokar

    2012-06-01

    Kinematic design is a predominant phase in the design of robotic manipulators for minimally invasive surgery (MIS). However, an extensive overview of the kinematic design issues for MIS robots is not yet available to both mechanisms and robotics communities. Hundreds of archival reports and articles on robotic systems for MIS are reviewed and studied. In particular, the kinematic design considerations and mechanism development described in the literature for existing robots are focused on. The general kinematic design goals, design requirements, and design preferences for MIS robots are defined. An MIS-specialized mechanism, namely the remote center-of-motion (RCM) mechanism, is revisited and studied. Accordingly, based on the RCM mechanism types, a classification for MIS robots is provided. A comparison between eight different RCM types is given. Finally, several open challenges for the kinematic design of MIS robotic manipulators are discussed. This work provides a detailed survey of the kinematic design of MIS robots, addresses the research opportunity in MIS robots for kinematicians, and clarifies the kinematic point of view to MIS robots as a reference for the medical community. Copyright © 2012 John Wiley & Sons, Ltd.

  4. Declining MIS Enrollment: The Death of the MIS Degree?

    ERIC Educational Resources Information Center

    Saunders, Gary; Lockridge, T. Maurice

    2011-01-01

    There is little doubt that enrollments in MIS degree programs have been declining since the recession in the technical industry in 2001. Reagan's research (2008) indicates that enrollments in MIS degree programs is only about 25% of the 2001 level. Many MIS (IS) programs have been abandoned or combined with other related programs. While many…

  5. Studies of Large-Area Inversion-Layer Metal-Insulator-Semiconductor (IL/MIS) Solar Cells and Arrays

    NASA Technical Reports Server (NTRS)

    Ho, Fat Duen

    1996-01-01

    Many inversion-layer metal-insulator-semiconductor (IL/MIS) solar cells have been fabricated. There are around eighteen 1 cm(exp 2) IL/MIS solar cells which have efficiencies greater than 7%. There are only about three 19 cm(exp 2) IL/MIS cells which have efficiencies greater than 4%. The more accurate control of the thickness of the thin layer of oxide between aluminum and silicon of the MIS contacts has been achieved. A lot of effort and progress have been made in this area. A comprehensive model for MIS contacts under dark conditions has been developed that covers a wide range of parameters. It has been applied to MIS solar cells. One of the main advantages of these models is the prediction of the range of the thin oxide thickness versus the maximum efficiencies of the MIS solar cells. This is particularly important when the thickness is increased to 25 A. This study is very useful for our investigation of the IL/MIS solar cells. The two-dimensional numerical model for the IL/MIS solar cells has been tried to develop and the results are presented in this report.

  6. Perioperative Cost Analysis of Minimally Invasive vs Open Resection of Intradural Extramedullary Spinal Cord Tumors.

    PubMed

    Fontes, Ricardo B V; Wewel, Joshua T; OʼToole, John E

    2016-04-01

    Minimally invasive spinal surgery (MIS) has emerged as a clinically effective tool but its cost-effectiveness remains unclear. No studies have compared MIS vs open surgical techniques for the treatment of intradural extramedullary (IDEM) tumors. To analyze and compare open and MIS techniques for resection of IDEM tumors, with focus on perioperative costs. Retrospective analysis of a prospectively collected database including 35 IDEM patients (18 open, 17 MIS). Perioperative data, hospital costs, and hospital and physician charges for in-hospital services associated with the index surgical procedure and readmissions within 90 days were compared. Mean estimated blood loss, operative time, preoperative hospital charges, and physician fees were similar between open and MIS techniques. Patient and tumor characteristics were similar between groups. MIS cases were associated with shorter intensive care unit and floor stay. There were 3 complications in the open group, requiring 2 readmissions and 1 reoperation. Hospital costs ($21 307.80 open, $15 015.20 MIS, P < .01), and postoperative ($75 383.48 open, $56 006.88 MIS, P < .01) and total charges ($100 779.38 open, $76 100.92 MIS, P < .01) were significantly lower in the MIS group. There were no tumor recurrences in either group. All patients except for one in the open group maintained or improved their Nurick score. Both MIS and open techniques were able to adequately treat IDEM tumors. Reductions in complication rate and intensive care unit and hospital stay led to a decrease in hospital costs of almost 30% in the MIS group. MIS resection of IDEM tumors is not only an effective and safe option, but allows faster hospital discharge and significant cost savings.

  7. DOE Office of Scientific and Technical Information (OSTI.GOV)

    Mitra, Kalyan Yoti, E-mail: kalyan-yoti.mitra@mb.tu-chemnitz.de, E-mail: enrico.sowade@mb.tu-chemnitz.de; Sowade, Enrico, E-mail: kalyan-yoti.mitra@mb.tu-chemnitz.de, E-mail: enrico.sowade@mb.tu-chemnitz.de; Martínez-Domingo, Carme

    Inkjet Technology is often mis-believed to be a deposition/patterning technology which is not meant for high fabrication throughput in the field of printed and flexible electronics. In this work, we report on the 1) printing, 2) fabrication yield and 3) characterization of exemplary simple devices e.g. capacitors, organic transistors etc. which are the basic building blocks for logical circuits. For this purpose, printing is performed first with a Proof of concept Inkjet printing system Dimatix Material Printer 2831 (DMP 2831) using 10 pL small print-heads and then with Dimatix Material Printer 3000 (DMP 3000) using 35 pL industrial print-heads (frommore » Fujifilm Dimatix). Printing at DMP 3000 using industrial print-heads (in Sheet-to-sheet) paves the path towards industrialization which can be defined by printing in Roll-to-Roll format using industrial print-heads. This pavement can be termed as 'Bridging Platform'. This transfer to 'Bridging Platform' from 10 pL small print-heads to 35 pL industrial print-heads help the inkjet-printed devices to evolve on the basis of functionality and also in form of up-scaled quantities. The high printed quantities and yield of inkjet-printed devices justify the deposition reliability and potential to print circuits. This reliability is very much desired when it comes to printing of circuits e.g. inverters, ring oscillator and any other planned complex logical circuits which require devices e.g. organic transistors which needs to get connected in different staged levels. Also, the up-scaled inkjet-printed devices are characterized and they reflect a domain under which they can work to their optimal status. This status is much wanted for predicting the real device functionality and integration of them into a planned circuit.« less

  8. Vegetation responses to interglacial warming in the Arctic: examples from Lake El'gygytgyn, Far East Russian Arctic

    NASA Astrophysics Data System (ADS)

    Lozhkin, A. V.; Anderson, P. M.

    2013-06-01

    Preliminary analyses of Lake El'gygytgyn sediment indicate a wide range of ecosystem responses to warmer than present climates. While palynological work describing all interglacial vegetation is ongoing, sufficient data exist to compare recent warm events (the postglacial thermal maximum, PGTM, and marine isotope stage, MIS5) with "super" interglaciations (MIS11, MIS31). Palynological assemblages associated with these climatic optima suggest two types of vegetation responses: one dominated by deciduous taxa (PGTM, MIS5) and the second by evergreen conifers (MIS11, MIS31). MIS11 forests show a similarity to modern Picea-Larix-Betula-Alnus forests of Siberia. While dark coniferous forest also characterizes MIS31, the pollen taxa show an affinity to the boreal forest of the lower Amur valley (southern Russian Far East). Despite vegetation differences during these thermal maxima, all glacial-interglacial transitions are alike, being dominated by deciduous woody taxa. Initially Betula shrub tundra established and was replaced by tundra with tree-sized shrubs (PGTM), Betula woodland (MIS5), or Betula-Larix (MIS11, MIS31) forest. The consistent occurrence of deciduous forest and/or high shrub tundra before the incidence of maximum warmth underscores the importance of this biome for modeling efforts. The El'gygytgyn data also suggest a possible elimination or massive reduction of Arctic plant communities under extreme warm-earth scenarios.

  9. Life Sciences MIS

    NASA Technical Reports Server (NTRS)

    Dittman, R. A.; Marks, V.

    1983-01-01

    Management Information System, MIS, provides Life Sciences Projects Division at Johnson Space Center with automated system for project managment. MIS utilizes Tektronix 4027 color graphics display terminal and form-fillout capability. User interface with MIS data base is through series of forms.

  10. Soil and climate modelling to explain soil differences in MIS5e and MIS13 on the Chinese Loess Plateau

    NASA Astrophysics Data System (ADS)

    Finke, P. A.; Yu, Y.; Yin, Q.; Bernardini, N. J.

    2016-12-01

    Objective Proxy records indicate that MIS5 (about 120 ka ago) was warmer than MIS13 (about 500 ka ago). Nevertheless, MIS13-soils in the Chinese loess plateau (105 -115°E and 30-40°N) are stronger developed than MIS5-soils. This has been attributed to a stronger East Asian summer monsoon. Other differences are interglacial lengths and loess deposition rates. We aimed to find explanations for soil development differences by using a soil formation model (SoilGen) with climatic inputs obtained from an earth system model (LOVECLIM). Material and Methods The LOVECLIM model is driven by time-varying insolation and greenhouse gas concentrations and was run to give monthly values for temperature, precipitation and evaporation as well the dominant vegetation type. Model results for were corrected for systematic differences between present-day observation data and simulation. Reconstructions were made for both interglacials of the amount of inblown loess, and the mineralogy and grain size distribution of the initial loess as well as the dust. These data were fed into the SoilGen model, which was used to calculate various soil parameters with depth and over time. Results Simulations show a stronger developed MIS13 soil, in terms of weathering (loss of anorthite), and redistribution of calcite, gypsum and clay. This corresponds to observed paleosoils. MIS13-soils are more leached. As simulated temperatures and annual precipitation between MIS5 and MIS13 did not vary strongly, the greater length of MIS13 seemed the main explanation for the stronger leaching and weathering. Closer analysis however showed a larger number of months in MIS13 with a precipitation surplus, even when only considering the first 22 ka. Only in such months significant leaching can occur. Conclusion Using simulation models it was demonstrated that the stronger soil expression in MIS13 than in MIS5 is likely caused by more months with a precipitation surplus, in combination with a longer duration of MIS13.

  11. Electrical and optical properties of diketopyrrolopyrrole-based copolymer interfaces in thin film devices.

    PubMed

    Adil, Danish; Kanimozhi, Catherine; Ukah, Ndubuisi; Paudel, Keshab; Patil, Satish; Guha, Suchi

    2011-05-01

    Two donor-acceptor diketopyrrolopyrrole (DPP)-based copolymers (PDPP-BBT and TDPP-BBT) have been synthesized for their application in organic devices such as metal-insulator semiconductor (MIS) diodes and field-effect transistors (FETs). The semiconductor-dielectric interface was characterized by capacitance-voltage and conductance-voltage methods. These measurements yield an interface trap density of 4.2 × 10(12) eV⁻¹ cm⁻² in TDPP-BBT and 3.5 × 10¹² eV⁻¹ cm⁻² in PDPP-BBT at the flat-band voltage. The FETs based on these spincoated DPP copolymers display p-channel behavior with hole mobilities of the order 10⁻³ cm²/(Vs). Light scattering studies from PDPP-BBT FETs show almost no change in the Raman spectrum after the devices are allowed to operate at a gate voltage, indicating that the FETs suffer minimal damage due to the metal-polymer contact or the application of an electric field. As a comparison Raman intensity profile from the channel-Au contact layer in pentacene FETs are presented, which show a distinct change before and after biasing.

  12. The feasibility of introducing advanced minimally invasive surgery into surgical practice

    PubMed Central

    Birch, Daniel W.; Misra, Monali; Farrokhyar, Forough

    2007-01-01

    Background This study investigates the feasibility of performing advanced minimally invasive surgery (MIS) in a nonspecialized practice environment. Methods We conducted a cross-sectional survey of all community general surgeons currently practising in Ontario. Results Few community surgeons perform a high volume (> 10 procedures per yr) of advanced MIS. Most (70%) believe it is important to acquire additional skills in advanced MIS. The most appropriate methods for learning advanced MIS are believed to be expert mentoring (79.7%), courses (77.2%) and a colleague mentor (63.9%). A total of 57.6% of respondents have attended a course in MIS while in practice, and most have access to a reasonable variety of instrumentation. Respondents believe that 57.6% of assistants, 54.8% of nurses and 43.4% of anaesthetists are relatively inexperienced with advanced MIS. Barriers to establishing advanced MIS include limited operating room access (50%), resources or equipment (45.2%) and limited expert mentoring (43.6%). Surgeons with less than 10 years of practice found lack of trained nursing staff (7.9% v. 4.2%, p = 0.01) and experienced assistants (12% v. 6.2%, p = 0.008) to be more important barriers than did those with over 10 years of practice, respectively. Conclusion Most general surgeons working in Ontario are self-taught with respect to MIS skills, and few perform a high volume of advanced MIS. Only one-half of all respondents have access to skilled MIS operating room nurses, surgical assistants or anesthesiology. Despite this, general surgeons perceive the greatest barriers to introducing advanced MIS procedures to be limited access to operating rooms, resources or equipment and limited mentoring. This study has shown that the role of the surgical team in advanced MIS may be underestimated by many general surgeons. These data have important implications in training general surgeons and in incorporating additional advanced MIS procedures into the armamentarium of general surgeons. PMID:17897513

  13. Minimally Invasive versus Open Spine Surgery: What Does the Best Evidence Tell Us?

    PubMed

    McClelland, Shearwood; Goldstein, Jeffrey A

    2017-01-01

    Spine surgery has been transformed significantly by the growth of minimally invasive surgery (MIS) procedures. Easily marketable to patients as less invasive with smaller incisions, MIS is often perceived as superior to traditional open spine surgery. The highest quality evidence comparing MIS with open spine surgery was examined. A systematic review of randomized controlled trials (RCTs) involving MIS versus open spine surgery was performed using the Entrez gateway of the PubMed database for articles published in English up to December 28, 2015. RCTs and systematic reviews of RCTs of MIS versus open spine surgery were evaluated for three particular entities: Cervical disc herniation, lumbar disc herniation, and posterior lumbar fusion. A total of 17 RCTs were identified, along with six systematic reviews. For cervical disc herniation, MIS provided no difference in overall function, arm pain relief, or long-term neck pain. In lumbar disc herniation, MIS was inferior in providing leg/low back pain relief, rehospitalization rates, quality of life improvement, and exposed the surgeon to >10 times more radiation in return for shorter hospital stay and less surgical site infection. In posterior lumbar fusion, MIS transforaminal lumbar interbody fusion (TLIF) had significantly reduced 2-year societal cost, fewer medical complications, reduced time to return to work, and improved short-term Oswestry Disability Index scores at the cost of higher revision rates, higher readmission rates, and more than twice the amount of intraoperative fluoroscopy. The highest levels of evidence do not support MIS over open surgery for cervical or lumbar disc herniation. However, MIS TLIF demonstrates advantages along with higher revision/readmission rates. Regardless of patient indication, MIS exposes the surgeon to significantly more radiation; it is unclear how this impacts patients. These results should optimize informed decision-making regarding MIS versus open spine surgery, particularly in the current advertising climate greatly favoring MIS.

  14. Electrical characteristics of TMAH-surface treated Ni/Au/Al2O3/GaN MIS Schottky structures

    NASA Astrophysics Data System (ADS)

    Reddy, M. Siva Pratap; Lee, Jung-Hee; Jang, Ja-Soon

    2014-03-01

    The electrical characteristics and reverse leakage mechanisms of tetramethylammonium hydroxide (TMAH) surface-treated Ni/Au/Al2O3/GaN metal-insulator-semiconductor (MIS) diodes were investigated by using the current-voltage ( I-V) and capacitance-voltage ( C-V) characteristics. The MIS diode was formed on n-GaN after etching the AlGaN in the AlGaN/GaN heterostructures. The TMAH-treated MIS diode showed better Schottky characteristics with a lower ideality factor, higher barrier height and lower reverse leakage current compared to the TMAH-free MIS diode. In addition, the TMAH-free MIS diodes exhibited a transition from Poole-Frenkel emission at low voltages to Schottky emission at high voltages, whereas the TMAH-treated MIS diodes showed Schottky emission over the entire voltage range. Reasonable mechanisms for the improved device-performance characteristics in the TMAH-treated MIS diode are discussed in terms of the decreased interface state density or traps associated with an oxide material and the reduced tunneling probability.

  15. Cost-utility analysis of minimally invasive versus open multilevel hemilaminectomy for lumbar stenosis.

    PubMed

    Parker, Scott L; Adogwa, Owoicho; Davis, Brandon J; Fulchiero, Erin; Aaronson, Oran; Cheng, Joseph; Devin, Clinton J; McGirt, Matthew J

    2013-02-01

    Two-year cost-utility study comparing minimally invasive (MIS) versus open multilevel hemilaminectomy in patients with degenerative lumbar spinal stenosis. The objective of the study was to determine whether MIS versus open multilevel hemilaminectomy for degenerative lumbar spinal stenosis is a cost-effective advancement in lumbar decompression surgery. MIS-multilevel hemilaminectomy for degenerative lumbar spinal stenosis allows for effective treatment of back and leg pain while theoretically minimizing blood loss, tissue injury, and postoperative recovery. No studies have evaluated comprehensive healthcare costs associated with multilevel hemilaminectomy procedures, nor assessed cost-effectiveness of MIS versus open multilevel hemilaminectomy. Fifty-four consecutive patients with lumbar stenosis undergoing multilevel hemilaminectomy through an MIS paramedian tubular approach (n=27) versus midline open approach (n=27) were included. Total back-related medical resource utilization, missed work, and health state values [quality adjusted life years (QALYs), calculated from EuroQuol-5D with US valuation] were assessed after 2-year follow-up. Two-year resource use was multiplied by unit costs based on Medicare national allowable payment amounts (direct cost) and work-day losses were multiplied by the self-reported gross-of-tax wage rate (indirect cost). Difference in mean total cost per QALY gained for MIS versus open hemilaminectomy was assessed as incremental cost-effectiveness ratio (ICER: COST(MIS)-COST(OPEN)/QALY(MIS)-QALY(OPEN)). MIS versus open cohorts were similar at baseline. MIS and open hemilaminectomy were associated with an equivalent cumulative gain of 0.72 QALYs 2 years after surgery. Mean direct medical costs, indirect societal costs, and total 2-year cost ($23,109 vs. $25,420; P=0.21) were similar between MIS and open hemilaminectomy. MIS versus open approach was associated with similar total costs and utility, making it a cost equivalent technology compared with the traditional open approach. MIS versus open multilevel hemilaminectomy was associated with similar cost over 2 years while providing equivalent improvement in QALYs. In our experience, MIS versus open multilevel hemilaminectomy is a cost equivalent technology for patients with lumbar stenosis-associated radicular pain.

  16. Physiological IgM Class Catalytic Antibodies Selective for Transthyretin Amyloid*

    PubMed Central

    Planque, Stephanie A.; Nishiyama, Yasuhiro; Hara, Mariko; Sonoda, Sari; Murphy, Sarah K.; Watanabe, Kenji; Mitsuda, Yukie; Brown, Eric L.; Massey, Richard J.; Primmer, Stanley R.; O'Nuallain, Brian; Paul, Sudhir

    2014-01-01

    Peptide bond-hydrolyzing catalytic antibodies (catabodies) could degrade toxic proteins, but acquired immunity principles have not provided evidence for beneficial catabodies. Transthyretin (TTR) forms misfolded β-sheet aggregates responsible for age-associated amyloidosis. We describe nucleophilic catabodies from healthy humans without amyloidosis that degraded misfolded TTR (misTTR) without reactivity to the physiological tetrameric TTR (phyTTR). IgM class B cell receptors specifically recognized the electrophilic analog of misTTR but not phyTTR. IgM but not IgG class antibodies hydrolyzed the particulate and soluble misTTR species. No misTTR-IgM binding was detected. The IgMs accounted for essentially all of the misTTR hydrolytic activity of unfractionated human serum. The IgMs did not degrade non-amyloidogenic, non-superantigenic proteins. Individual monoclonal IgMs (mIgMs) expressed variable misTTR hydrolytic rates and differing oligoreactivity directed to amyloid β peptide and microbial superantigen proteins. A subset of the mIgMs was monoreactive for misTTR. Excess misTTR was dissolved by a hydrolytic mIgM. The studies reveal a novel antibody property, the innate ability of IgMs to selectively degrade and dissolve toxic misTTR species as a first line immune function. PMID:24648510

  17. Late to middle Pleistocene Arctic glacial history implied from a sedimentary record from the Northwind Ridge

    NASA Astrophysics Data System (ADS)

    Liu, Y.; Dong, L.; Shi, X.; Zhu, A.

    2017-12-01

    Abstract: Sediment core ARC6-C21 collected from the Northwind Ridge, western Arctic Ocean, covers the late to middle Quaternary (Marine Isotope Stages (MIS) 1-11), as estimated by correlation to earlier proposed Arctic Ocean stratigraphies and AMS14C dating of the youngest sediments. Detailed examination of the elemental composition of sediment along with grain size in core ARC6-C21 provides important new information about sedimentary environments and provenance. We use increased contents of coarse debris as an indicator of glacier collapse events at the margins of the western Arctic Ocean, and identify the provenance of these events from geochemical composition. Notably, peaks of MgO and CaO, including large dropstones, presumably track the Laurentide Ice Sheet (LIS) discharge events to the Arctic Ocean. Major LIS inputs occurred during the stratigraphic intervals estimated as MIS 3, intra-MIS 5 and 7 events, MIS 8, and MIS 10. Inputs from the East Siberian Ice Sheet (ESIS) and/or Eurasia Ice Sheet (EIS)are inferred from peaks of SiO2, K2O and Na2O associated with coarse sediment. Major ESIS and/or EIS sedimentary events occurred in the intervals estimated as MIS 2, MIS 4, MIS 6, MIS 8 and MIS 10. Keywords: Sediment core, Pleistocene, western Arctic Ocean, geochemistry, grain size, sediment provenance, glaciations

  18. Potential System Integration Issues in the Joint Multi-Role (JMR) Joint Common Architecture (JCA) Demonstration System

    DTIC Science & Technology

    2015-12-01

    the MIS System/Subsystem Specification ( SSS ), and supplementary BAA document. On June 26, 2014, the SEI provided a draft interim report of the...findings and issues. The SEI team also received July 3, 2014, versions of the MIS Stakeholder Requirements, MIS SSS , and build plan and July 17, 2014...versions of the MIS SSS together with the MIS system model. On July 14–15, 2014, the SEI presented a summary of the issues at the two contractors

  19. AMH/MIS as a contraceptive that protects the ovarian reserve during chemotherapy.

    PubMed

    Kano, Motohiro; Sosulski, Amanda E; Zhang, LiHua; Saatcioglu, Hatice D; Wang, Dan; Nagykery, Nicholas; Sabatini, Mary E; Gao, Guangping; Donahoe, Patricia K; Pépin, David

    2017-02-28

    The ovarian reserve represents the stock of quiescent primordial follicles in the ovary which is gradually depleted during a woman's reproductive lifespan, resulting in menopause. Müllerian inhibiting substance (MIS) (or anti-Müllerian hormone/AMH), which is produced by granulosa cells of growing follicles, has been proposed as a negative regulator of primordial follicle activation. Here we show that long-term parenteral administration of superphysiological doses of MIS, using either an adeno-associated virus serotype 9 (AAV9) gene therapy vector or recombinant protein, resulted in a complete arrest of folliculogenesis in mice. The ovaries of MIS-treated mice were smaller than those in controls and did not contain growing follicles but retained a normal ovarian reserve. When mice treated with AAV9/MIS were paired with male breeders, they exhibited complete and permanent contraception for their entire reproductive lifespan, disrupted vaginal cycling, and hypergonadotropic hypogonadism. However, when ovaries from AAV9-MIS-treated mice were transplanted orthotopically into normal recipient mice, or when treatment with the protein was discontinued, folliculogenesis resumed, suggesting reversibility. One of the important causes of primary ovarian insufficiency is chemotherapy-induced primordial follicle depletion, which has been proposed to be mediated in part by increased activation. To test the hypothesis that MIS could prevent chemotherapy-induced overactivation, mice were given carboplatin, doxorubicin, or cyclophosphamide and were cotreated with AAV9-MIS, recombinant MIS protein, or vehicle controls. We found significantly more primordial follicles in MIS-treated animals than in controls. Thus treatment with MIS may provide a method of contraception with the unique characteristic of blocking primordial follicle activation that could be exploited to prevent the primary ovarian insufficiency often associated with chemotherapy.

  20. The integration of minimally invasive surgery in surgical practice in a Canadian setting: results from 2 consecutive province-wide practice surveys of general surgeons over a 5-year period

    PubMed Central

    Hallet, Julie; Mailloux, Olivier; Chhiv, Mony; Grégoire, Roger C.; Gagné, Jean-Pierre

    2015-01-01

    Background Although minimally invasive surgery (MIS) has been quickly embraced, the introduction of advanced procedures appears more complex. We assessed the evolution of MIS in the province of Quebec over a 5-year period to identify areas for improvement in the modern surgical era. Methods We developed, test-piloted and conducted a self-administered questionnaire among Quebec general surgeons in 2007 and 2012 to examine stated MIS practice, MIS training and barriers and facilitators to the use of MIS. Results Response rates were 51.3% (251 of 489) in 2007 and 31.3% (153 of 491) in 2012. A significant increase was observed for performance of most advanced MIS procedures, especially for colectomy for benign (66.0% v. 84.3%, p < 0,001) and malignant diseases (43.3% v. 77.8%, p < 0,001) and for rectal surgery for malignancy (21.0% v. 54.6%, p < 0.001). More surgeons practised 3 or more advanced MIS procedures in 2012 than in 2007 (82.3% v. 64.3%, p < 0,001). At multivariate analysis, the 2007 survey administration was associated with fewer surgeons practising advanced MIS (odds ratio 0.13, 95% confidence interval 0.06–0.29). In 2012, more respondents stated they gained their skills during residency (p = 0.028). Conclusion From 2007 to 2012 there was a significant increase in advanced MIS procedures practised by general surgeons in Québec. This technique appears well established in current surgical practice. The growing place of MIS in residency training seems to be a paramount part of this development. Results from this study could be used as a baseline for studies focusing on ways to further improve the MIS practice. PMID:25598180

  1. A comparison of open and minimally invasive surgery for hepatic and pancreatic resections using the nationwide inpatient sample

    PubMed Central

    Ejaz, Aslam; Sachs, Teviah; He, Jin; Spolverato, Gaya; Hirose, Kenzo; Ahuja, Nita; Wolfgang, Christopher L.; Makary, Martin A.; Weiss, Matthew; Pawlik, Timothy M.

    2015-01-01

    Background The use of minimally invasive surgery (MIS) techniques for pancreatic and liver operations remains ill defined. We sought to compare inpatient outcomes among patients undergoing open versus MIS pancreas and liver operations using a nationally representative cohort. Methods We queried the Nationwide Inpatient Sample database for all major pancreatic and hepatic resections performed between 2000 and 2011. Appropriate International Classification of Diseases, 9th Revision (ICD-9) coding modifiers for laparoscopy and robotic assist were used to categorize procedures as MIS. Demographics, comorbidities, and inpatient outcomes were compared between the open and MIS groups. Results A total of 65,033 resections were identified (pancreas, n = 36,195 [55.7%]; liver, n = 28,035 [43.1%]; combined pancreas and liver, n = 803 [1.2%]). The overwhelming majority of operations were performed open (n = 62,192, 95.6%), whereas 4.4% (n = 2,841) were MIS. The overall use of MIS increased from 2.3% in 2000 to 7.5% in 2011. Compared with patients undergoing an open operation, MIS patients were older and had a greater incidence of multiple comorbid conditions. After operation, the incidence of complications for MIS (pancreas, 35.4%; liver, 29.5%) was lower than for open (pancreas, 41.6%; liver, 33%) procedures (all P < .05) resulting in a shorter median length of stay (8 vs 7 days; P = .001) as well as a lower in-hospital mortality (5.1% vs 2.8%; P = .001). Conclusion During the last decade, the number of MIS pancreatic and hepatic operations has increased, with nearly 1 in 13 HPB cases now being performed via an MIS approach. Despite MIS patients tending to have more preoperative medical comorbidities, postoperative morbidity, mortality, and duration of stay compared favorably with open surgery. PMID:25017135

  2. Uracil misincorporation into DNA and folic acid supplementation123

    PubMed Central

    Selhub, Jacob; Chao, Wei-Hsun; Ueland, Per Magne; Hunter, David J; Baron, John A

    2010-01-01

    Background: Folate deficiency decreases thymidylate synthesis from deoxyuridylate, which results in an imbalance of deoxyribonucleotide that may lead to excessive uracil misincorporation (UrMis) into DNA during replication and repair. Objective: We evaluated the relation between UrMis in different tissues and the effect of folate supplementation on UrMis. Design: We analyzed UrMis concentrations in rectal mucosa (n = 92) and white blood cells (WBCs; n = 60) among individuals randomly assigned to receive supplementation with 1 mg folate/d or placebo, who were then evaluated for colorectal adenoma recurrence. Results: As expected, total homocysteine was significantly lower among the study participants who received active folate treatment (Wilcoxon's P = 0.003) than among those in the placebo group. The median UrMis concentration in rectal mucosa and WBCs among individuals treated with folate was not significantly lower than that in those who received placebo (Wilcoxon's P = 0.17). UrMis concentrations in both rectal mucosa and WBCs did not correlate significantly with folate measured in plasma and red blood cells. UrMis in rectal mucosa was marginally associated with an increased risk of adenoma recurrence (odds ratio per SD: 1.43; 95% CI: 0.91, 2.25). Conclusions: UrMis measurements in WBCs are not a robust surrogate for UrMis measurements in the rectal mucosa (Spearman correlation coefficient = 0.23, P = 0.08). Furthermore, folate supplementation in an already replete population (half treated with folic acid supplements and all exposed to folic acid fortification of the food supply) was not significantly associated with reduced UrMis in rectal mucosa cells or WBCs. Large-scale studies are needed to evaluate whether excessive UrMis concentrations are an important risk factor for colorectal neoplasia. This trial was registered at clinicaltrials.gov as NCT00272324. PMID:19923375

  3. Minimally invasive surgery in veterinary practice: a 2010 survey of diplomates and residents of the American College of Veterinary Surgeons.

    PubMed

    Bleedorn, Jason A; Dykema, Jennifer L; Hardie, Robert J

    2013-08-01

    To report the current state of minimally invasive surgery (MIS) in veterinary surgical practice in 2010. Electronic questionnaire. Diplomates and residents of the American College of Veterinary Surgeons (ACVS). A survey (38 questions for Diplomates, 23 questions for residents) was sent electronically to 1216 Diplomates and 300 residents. Questions were organized into 5 categories to investigate: (1) caseload and distribution of MIS cases; (2) MIS training; (3) MIS benefits, morbidity, limitations and motivating factors; (4) ACVS role; and (5) demographics of the study population. Eighty-six percent of small animal (SA) Diplomates, 99% of large animal (LA) Diplomates, and 98% of residents had performed MIS. Median LA caseload (30 cases/year; range, 1-600) was significantly higher than SA caseload (20 cases/year; range, 1-350). Descending order of case distribution was: arthroscopy > laparoscopy > endoscopic upper airway > thoracoscopy. Sixty percent of Diplomates and 98% of residents received MIS training during their residency. Residents' perspective of MIS training proficiency was positively correlated to caseload. Ninety-five percent of all respondents felt postoperative morbidity was less with MIS, and were motivated by patient benefits, maintaining a high standard of care, and personal interests. Fifty-eight percent of Diplomates and 89% of residents felt ACVS should be involved in developing MIS training. MIS is widely used by ACVS Diplomates and residents in clinical practice; however, important differences exist between SA and LA surgeons and practice types. MIS training in partnership with the ACVS is needed for continued development in veterinary surgery. © Copyright 2013 by The American College of Veterinary Surgeons.

  4. Ice Complex permafrost of MIS5 age in the Dmitry Laptev Strait coastal region (East Siberian Arctic)

    NASA Astrophysics Data System (ADS)

    Wetterich, Sebastian; Tumskoy, Vladimir; Rudaya, Natalia; Kuznetsov, Vladislav; Maksimov, Fedor; Opel, Thomas; Meyer, Hanno; Andreev, Andrei A.; Schirrmeister, Lutz

    2016-09-01

    Ice Complex deposits (locally known as the Buchchagy Ice Complex) are exposed at both coasts of the East Siberian Dmitry Laptev Strait and preserved below the Yedoma Ice Complex that formed during MIS3 and MIS2 (Marine Isotope Stage) and lateglacial-Holocene thermokarst deposits (MIS1). Radioisotope disequilibria (230Th/U) of peaty horizons date the Buchchagy Ice Complex deposition to 126 + 16/-13 kyr and 117 + 19/-14 kyr until 98 ± 5 kyr and 89 ± 5 kyr. The deposit is characterised by poorly-sorted medium-to-coarse silts with cryogenic structures of horizontal ice bands, lens-like, and lens-like reticulated segregation ice. Two peaty horizons within the Buchchagy Ice Complex and syngenetic ice wedges (2-4 m wide, up to 10 m high) are striking. The isotopic composition (δ18O, δD) of Buchchagy ice-wedge ice indicates winter conditions colder than during the MIS3 interstadial and warmer than during MIS2 stadial, and similar atmospheric winter moisture sources as during the MIS2 stadial. Buchchagy Ice Complex pollen spectra reveal tundra-steppe vegetation and harsher summer conditions than during the MIS3 interstadial and rather similar vegetation as during the MIS2 stadial. Short-term climatic variability during MIS5 is reflected in the record. Even though the regional chronostratigraphic relationship of the Buchchagy Ice Complex to the Last Interglacial remains unclear because numerical dating is widely lacking, the present study indicates permafrost (Ice Complex) formation during MIS5 sensu lato, and its preservation afterwards. Palaeoenvironmental insights into past climate and the periglacial landscape dynamics of arctic lowlands in eastern Siberia are deduced from the record.

  5. Does MIS Surgery Allow for Shorter Constructs in the Surgical Treatment of Adult Spinal Deformity?

    PubMed

    Uribe, Juan S; Beckman, Joshua; Mummaneni, Praveen V; Okonkwo, David; Nunley, Pierce; Wang, Michael Y; Mundis, Gregory M; Park, Paul; Eastlack, Robert; Anand, Neel; Kanter, Adam; Lamarca, Frank; Fessler, Richard; Shaffrey, Chris I; Lafage, Virginie; Chou, Dean; Deviren, Vedat

    2017-03-01

    The length of construct can potentially influence perioperative risks in adult spinal deformity (ASD) surgery. A head-to-head comparison between open and minimally invasive surgery (MIS) techniques for treatment of ASD has yet to be performed. To examine the impact of MIS approaches on construct length and clinical outcomes in comparison to traditional open approaches when treating similar ASD profiles. Two multicenter databases for ASD, 1 involving MIS procedures and the other open procedures, were propensity matched for clinical and radiographic parameters in this observational study. Inclusion criteria were ASD and minimum 2-year follow-up. Independent t -test and chi-square test were used to evaluate and compare outcomes. A total of 1215 patients were identified, with 84 patients matched in each group. Statistical significance was found for mean levels fused (4.8 for circumferential MIS [cMIS] and 10.1 for open), mean interbody fusion levels (3.6 cMIS and 2.4 open), blood loss (estimated blood loss 488 mL cMIS and 1762 mL open), and hospital length of stay (6.7 days cMIS and 9.7 days open). There was no significant difference in preoperative radiographic parameters or postoperative clinical outcomes (Owestry Disability Index and visual analog scale) between groups. There was a significant difference in postoperative lumbar lordosis (43.3° cMIS and 49.8° open) and pelvic incidence-lumbar lordosis correction (10.6° cMIS and 5.2° open) in the open group. There was no significant difference in reoperation rate between the 2 groups. MIS techniques for ASD may reduce construct length, reoperation rates, blood loss, and length of stay without affecting clinical and radiographic outcomes when compared to a similar group of patients treated with open techniques. Copyright © 2017 by the Congress of Neurological Surgeons

  6. Evolution of open radical retropubic prostatectomy--how have open surgeons responded to the challenge of minimally invasive surgery?

    PubMed

    Acharya, Sujeet S; Zorn, Kevin C; Shikanov, Sergey; Thong, Alan; Zagaja, Gregory P; Shalhav, Arieh L; Steinberg, Gary D

    2009-11-01

    With the advent of minimally invasive surgery (MIS) for treating urologic malignancies, emphasis has been placed on reducing patient morbidity and resuming normal activity. We sought to clarify whether open surgeons (OS) have modified their techniques, surgical equipment, and perioperative management in response to this trend. A survey sent to all members of the Society of Urologic Oncology assessed changes that OS performing radical retropubic prostatectomy have made in analgesia, operative technique, perioperative management, and follow-up patterns. We also assessed OS sense of competition from MIS. Surgeon perception of the influence MIS had on these changes was scored from 0 to 4 (0 = not at all, 1 = slightly, 2 = moderately, 3 = greatly, 4 =completely). Overall and major influence by MIS included scores 1-4 and 3-4, respectively. Reduced radical retropubic prostatectomy (RRP) case volume because of MIS competition was reported by 20 OS (24%), with 27 OS (32%) starting to perform MIS, and 20 (24%) doing mostly/exclusively MIS. MIS has influenced OS to reduce incision length (overall influence 56%/major influence 33%), operative time (40%/12%), blood loss (31%/17%), and transfusion rate (33%/14%). MIS has influenced OS to use new instruments (48%/44%) or loupes (20%/9%), modify dissection (45%/31%) or anastomotic technique (14%/12%), and increase the use of hemostatic agents (48%/19%). MIS has reduced convalescence in OS patients by reducing length of stay (52%/28%), time to a regular diet (40%/18%), duration of drain (21%/16%) and Foley (32%/15%), time to return to work (49%/25%), and exercise (44%/21%). MIS has changed follow-up of OS patients by increasing the use of clinical pathways (14%/9%) and validated questionnaires (22%/13%). To date, the influence of MIS on the OS has not been comprehensively assessed. This survey finds that OS report that MIS serves as major competition to the open technique and that it has influenced them to modify their surgical technique, reduce convalescence, and alter follow-up recommendations.

  7. Volcanic synchronization of Dome Fuji and Dome C Antarctic deep ice cores over the past 216 kyr

    NASA Astrophysics Data System (ADS)

    Fujita, S.; Parrenin, F.; Severi, M.; Motoyama, H.; Wolff, E. W.

    2015-10-01

    Two deep ice cores, Dome Fuji (DF) and EPICA Dome C (EDC), drilled at remote dome summits in Antarctica, were volcanically synchronized to improve our understanding of their chronologies. Within the past 216 kyr, 1401 volcanic tie points have been identified. DFO2006 is the chronology for the DF core that strictly follows O2 / N2 age constraints with interpolation using an ice flow model. AICC2012 is the chronology for five cores, including the EDC core, and is characterized by glaciological approaches combining ice flow modelling with various age markers. A precise comparison between the two chronologies was performed. The age differences between them are within 2 kyr, except at Marine Isotope Stage (MIS) 5. DFO2006 gives ages older than AICC2012, with peak values of 4.5 and 3.1 kyr at MIS 5d and MIS 5b, respectively. Accordingly, the ratios of duration (AICC2012 / DFO2006) range between 1.4 at MIS 5e and 0.7 at MIS 5a. When making a comparison with accurately dated speleothem records, the age of DFO2006 agrees well at MIS 5d, while the age of AICC2012 agrees well at MIS 5b, supporting their accuracy at these stages. In addition, we found that glaciological approaches tend to give chronologies with younger ages and with longer durations than age markers suggest at MIS 5d-6. Therefore, we hypothesize that the causes of the DFO2006-AICC2012 age differences at MIS 5 are (i) overestimation in surface mass balance at around MIS 5d-6 in the glaciological approach and (ii) an error in one of the O2 / N2 age constraints by ~ 3 kyr at MIS 5b. Overall, we improved our knowledge of the timing and duration of climatic stages at MIS 5. This new understanding will be incorporated into the production of the next common age scale. Additionally, we found that the deuterium signals of ice, δDice, at DF tends to lead the one at EDC, with the DF lead being more pronounced during cold periods. The lead of DF is by +710 years (maximum) at MIS 5d, -230 years (minimum) at MIS 7a and +60 to +126 years on average.

  8. Late Quaternary environmental changes inferred from n-alkane evidence in coastal area of southern Hainan Island, China

    NASA Astrophysics Data System (ADS)

    Wang, Mengyuan; Zheng, Zhuo

    2016-04-01

    The studied core was a coastal core in Hainan Island, China. It is in length of 49.01m and divided into four Units (MIS 1~MIS 6) according to lithology description. The Optically Stimulated Luminescence (OSL) attributes the sediments from Unit 3 to the Oxygen Isotope Stage of MIS 5e (Unit 3b and 3c) and 5d (Unit 3a). To interpret the origination of organic carbons and to reconstruct paleovegetation changes, n-alkane, δ13C and TOC have been used in the present research. The result of n-alkanes distribution indicates a series of changes of sedimentary environment and terrestrial input. The shallow water facies at Unit 2, 3a and 4 is mainly characterized by short carbon chain n-alkanes and relatively low concentration. Contrasting with that of deep-water marine facies of MIS 5e (Unit 3b), the n-alkane pattern is typical bimodal and the main peaks are both in short and long carbon chains. During Unit 3b-1 (MIS 5e), more terrestrial original n-alkanes contribute to the concentration of TOC than oceanic. Organic matter source is mainly terrestrial origination. Total organic matter input mechanism of TLG-01 correlates with sediment grain size (average grain size). Total organic carbon input is enhanced with the increasing of fine grain size component. The variation of CPI (25-33) value in this study correlates with hydrological energy. The highest CPI (25-33) value is shown in the high sea level period of MIS 5e, comparing with that in MIS 5d and MIS 1. High CPI value corresponds to high TOC and average grain size (Φ) value. In the weak hydrological energy sedimentary environment, more terrestrial organic matter, together with TOC, deposit in the study area. ACL (25-33) index display higher values in the interglacial period (MIS 5 and MIS 1) than MIS 3 (sediments weathered during MIS 2) and MIS 6. Paq proxy, together with δ13C, estimates the mangrove growing depth in MIS 5e. The correlation between δ13C and each carbon chain alkane state stabilize and turbulence of sedimentary environment in MIS 5e. Sediments deposit in stable weak hydrological energy environment show order and grouped alkanes distribution (Unit 3b-2). High and positive correlation coefficients of δ13C and each carbon chain alkane show the dominant alkanes contributed to organic carbon (δ13C).

  9. Large shifts in vegetation and climate during the Early Weichselian (MIS 5d-c) inferred from multi-proxy evidence at Sokli (northern Finland)

    NASA Astrophysics Data System (ADS)

    Helmens, Karin F.; Väliranta, Minna; Engels, Stefan; Shala, Shyhrete

    2012-05-01

    For decades, detailed studies on Early Weichselian deposits have been made in central Europe. In contrast, these studies are rare in Fennoscandia in northern Europe. We here integrate an extensive multi-proxy data set obtained on sediments of MIS 5d-c age that form part of a long sediment record preserved at Sokli in northern Finland. We make a detailed interpretation of the vegetation and depositional history for MIS 5d-c using pollen, macrofossils, diatoms and other siliceous microfossils, insect remains, and sediment characteristics, and combine these data with recently published estimates on July temperatures based on chironomids and selected plant indicator species in order to make inferences of paleo-climate regimes. The fossil record obtained on the seven meter thick MIS 5d-c deposit at Sokli is exceptionally rich in species due to the large variety of habitats associated with an overall fluvial depositional environment. A braided river system flanked by steppe-tundra vegetation is inferred for MIS 5d. Mean July temperatures of at least 12-14 °C are indicated by chironomids and plant indicator species and are in agreement with the presence of conifers and birch trees as recorded by macrofossils. The reconstructed environmental conditions suggest strong continental climate conditions at Sokli during MIS 5d. The gradual infilling of an oxbow lake and subsequent return to stream channel deposition is traced in great detail in the overlying gyttja and gravelly sediment of MIS 5c age. The terrestrial pollen and plant macrofossil record from the gyttja shows the establishment of birch forest followed by the spread of pine and then spruce. Rich plant indicator species assemblages indicate that the boreal environment at Sokli during MIS 5c experienced July temperatures several degrees higher than the present-day value of 13 °C. The high summer temperatures and presence of larch suggest more continental conditions. More open vegetation returned at Sokli during late MIS 5c and was followed by glaciation by the Fennoscandian Ice Sheet (MIS 5b). Despite the major differences in zonal vegetation types during MIS 5d-c, differences in reconstructed July temperatures are minor and suggest that winter temperatures combined with precipitation values mostly determined the stadial-interstadial climate variability. The most compelling conclusion from our study is that forest development during MIS 5c was remarkably similar to that recorded for the Eemian (MIS 5e) and Holocene Interglacials at the high-latitude site Sokli, and also to that inferred from MIS 5c sediments on the northern European mainland. Our results question the definition of MIS 5c in the terrestrial record of Europe as an interstadial interval of the last glacial cycle and suggest inclusion of MIS 5c together with the Eemian (MIS 5e) in an interglacial complex.

  10. The role of ultra-thin SiO2 layers in metal-insulator-semiconductor (MIS) photoelectrochemical devices (Presentation Recording)

    NASA Astrophysics Data System (ADS)

    Esposito, Daniel V.

    2015-08-01

    Solid-state junctions based on a metal-insulator-semiconductor (MIS) architecture are of great interest for a number of optoelectronic applications such as photovoltaics, photoelectrochemical cells, and photodetection. One major advantage of the MIS junction compared to the closely related metal-semiconductor junction, or Schottky junction, is that the thin insulating layer (1-3 nm thick) that separates the metal and semiconductor can significantly reduce the density of undesirable interfacial mid-gap states. The reduction in mid-gap states helps "un-pin" the junction, allowing for significantly higher built-in-voltages to be achieved. A second major advantage of the MIS junction is that the thin insulating layer can also protect the underlying semiconductor from corrosion in an electrochemical environment, making the MIS architecture well-suited for application in (photo)electrochemical applications. In this presentation, discontinuous Si-based MIS junctions immersed in electrolyte are explored for use as i.) photoelectrodes for solar-water splitting in photoelectrochemical cells (PECs) and ii.) position-sensitive photodetectors. The development and optimization of MIS photoelectrodes for both of these applications relies heavily on understanding how processing of the thin SiO2 layer impacts the properties of nano- and micro-scale MIS junctions, as well as the interactions of the insulating layer with the electrolyte. In this work, we systematically explore the effects of insulator thickness, synthesis method, and chemical treatment on the photoelectrochemical and electrochemical properties of these MIS devices. It is shown that electrolyte-induced inversion plays a critical role in determining the charge carrier dynamics within the MIS photoelectrodes for both applications.

  11. The MIS 5 palaeoenvironmental record in the SE Mediterranean coast of the Iberian Peninsula (Río Antas, Almería, Spain)

    NASA Astrophysics Data System (ADS)

    Torres, T.; Ortiz, J. E.; Blázquez, A. M.; Ruiz Zapata, B.; Gil, M. J.; Martín, T.; Sánchez-Palencia, Y.

    2015-08-01

    Landwards of a MIS5 bar, a borehole core (SRA) was analyzed to establish the relationship between the lagoonal record and the raised beach deposits in the surroundings of the Antas river mouth and to reconstruct the Pleistocene palaeoenvironmental evolution of the southern Mediterranean coast of the Iberian Peninsula. 63 samples were recovered for amino acid racemization dating, 86 samples for sedimentological and paleontological determination, 37 samples for pollen identification and 54 for biomarker analysis. AAR revealed that the borehole record contains MIS11, MIS6 and MIS5 deposits, the latter extensively represented. During the end of MIS6 and MIS5, a sand barrier developed and created a shallow lagoon with alternating terrestrial inputs this process being common in other Mediterranean realms. Litho- and biofacies allowed the identification of distinct paleoenvironments through time, with the presence of a lagoonal environment alternating with alluvial fan progradation. Biomarkers indicated constant input from terrestrial plants, together with variable development of aquatic macrophytes. The palynological content allowed the reconstruction of the paleoclimatological conditions during MIS6 and 5, with evidence of seven scenarios characterized by alternating arid and relatively humid conditions.

  12. Different nature of glacial CaCO3 constituents between MIS 2 and MIS 12 in the East Sea/Japan Sea and its paleoceanographic implication

    NASA Astrophysics Data System (ADS)

    Khim, Boo-Keun; Tada, Ryuji; Itaki, Takuya

    2014-05-01

    Two piston cores (PC-05 and PC-08) were collected on the Yamato Rise in the East Sea/Japan Sea during the KR07-12 cruise. A composite core was achieved with the successful replacement of almost half of the upper part of core PC-05 by the entirety of core PC-08 based on the co-equivalence of L* values and the dark layers, because an interval (170 cm to 410 cm) of core PC-05 was considerably disturbed due to fluidization during the core execution. Chronostratigraphy of the composite core was constructed by the direct comparison of L* values to the well-dated core MD01-2407 that was obtained in the Oki Ridge. The lower-bottom of the composite core reached back to Marine Isotope Stage (MIS) 14, based on the age estimate by LR04 stacks. Downcore opal variation of the composite core exhibited the distinct orbital-scale cyclic changes; high during the interglacial and low during the glacial periods. However, downcore CaCO3 variation showed no corresponding orbital-scale cyclic change between glacial and interglacial periods. Some intervals of both periods were high in CaCO3 content. Frequent and large fluctuations in CaCO3 content seemed to be more related to the presence of dark layers containing thin lamination (TL) within the glacial and interglacial intervals. It is worthy to note that MIS 2 and MIS 12 are characterized by distinctly high CaCO3 content, showing up to 18% and 73%, respectively, among the glacial periods. Furthermore, in terms of lithology, MIS 2 was characterized by a thick dark layer (low L* values) with TL, whereas MIS 12 preserved the distinctly light layer (high L* values) with parallel laminations. Another remarkable dissimilarity between MIS 2 and MIS 12 was the nature of their CaCO3 constituent; the CaCO3 constituent of MIS 2 consisted of mostly planktonic foraminifera, whereas that of MIS 12 was mostly dump of coccolithophorids, regardless the presence of planktonic foraminifera. The distinctness of the CaCO3 constituents between MIS 2 and MIS 12 indicates that the preservation of CaCO3 contents was different temporarily during the glacial periods in the East Sea/Japan Sea. Enhanced CaCO3 preservation in MIS 2 is attributed primarily to less dissolution during the sinking through the water column or at the seafloor, but increased CaCO3 preservation in MIS 12 is mainly due to the high primary production in the surface water. With respect to the different function of the biological pump which controls CO2 cycles, the East Sea/Japan Sea clearly experienced carbonate-ocean-like state during MIS 12, despite normally silica-ocean-like state.

  13. Toward optimal implementation of cancer prevention and control programs in public health: a study protocol on mis-implementation.

    PubMed

    Padek, Margaret; Allen, Peg; Erwin, Paul C; Franco, Melissa; Hammond, Ross A; Heuberger, Benjamin; Kasman, Matt; Luke, Doug A; Mazzucca, Stephanie; Moreland-Russell, Sarah; Brownson, Ross C

    2018-03-23

    Much of the cancer burden in the USA is preventable, through application of existing knowledge. State-level funders and public health practitioners are in ideal positions to affect programs and policies related to cancer control. Mis-implementation refers to ending effective programs and policies prematurely or continuing ineffective ones. Greater attention to mis-implementation should lead to use of effective interventions and more efficient expenditure of resources, which in the long term, will lead to more positive cancer outcomes. This is a three-phase study that takes a comprehensive approach, leading to the elucidation of tactics for addressing mis-implementation. Phase 1: We assess the extent to which mis-implementation is occurring among state cancer control programs in public health. This initial phase will involve a survey of 800 practitioners representing all states. The programs represented will span the full continuum of cancer control, from primary prevention to survivorship. Phase 2: Using data from phase 1 to identify organizations in which mis-implementation is particularly high or low, the team will conduct eight comparative case studies to get a richer understanding of mis-implementation and to understand contextual differences. These case studies will highlight lessons learned about mis-implementation and identify hypothesized drivers. Phase 3: Agent-based modeling will be used to identify dynamic interactions between individual capacity, organizational capacity, use of evidence, funding, and external factors driving mis-implementation. The team will then translate and disseminate findings from phases 1 to 3 to practitioners and practice-related stakeholders to support the reduction of mis-implementation. This study is innovative and significant because it will (1) be the first to refine and further develop reliable and valid measures of mis-implementation of public health programs; (2) bring together a strong, transdisciplinary team with significant expertise in practice-based research; (3) use agent-based modeling to address cancer control implementation; and (4) use a participatory, evidence-based, stakeholder-driven approach that will identify key leverage points for addressing mis-implementation among state public health programs. This research is expected to provide replicable computational simulation models that can identify leverage points and public health system dynamics to reduce mis-implementation in cancer control and may be of interest to other health areas.

  14. Developing an Introductory Level MIS Project in Accordance with AACSB Assurance of Learning Standard 15

    ERIC Educational Resources Information Center

    Schwieger, Dana

    2012-01-01

    As part of the introductory level management information systems (MIS) course, faculty are asked to introduce the students to MIS concepts as well as to help them develop technology-related skills benefitting them in their course work and beyond. However, with a vast array of MIS topics that could be covered and class time at a premium, it is…

  15. Centennial-scale vegetation dynamics and climate variability in SE Europe during Marine Isotope Stage 11 based on a pollen record from Lake Ohrid

    NASA Astrophysics Data System (ADS)

    Kousis, Ilias; Koutsodendris, Andreas; Peyron, Odile; Leicher, Niklas; Francke, Alexander; Wagner, Bernd; Giaccio, Biagio; Knipping, Maria; Pross, Jörg

    2018-06-01

    To better understand climate variability during Marine Isotope Stage (MIS) 11, we here present a new, centennial-scale-resolution pollen record from Lake Ohrid (Balkan Peninsula) derived from sediment cores retrieved during an International Continental Scientific Drilling Program (ICDP) campaign. Our palynological data, augmented by quantitative pollen-based climate reconstructions, provide insight into the vegetation dynamics and thus also climate variability in SE Europe during one of the best orbital analogues for the Holocene. Comparison of our palynological results with other proxy data from Lake Ohrid as well as with regional and global climate records shows that the vegetation in SE Europe responded sensitively both to long- and short-term climate change during MIS 11. The chronology of our palynological record is based on orbital tuning, and is further supported by the detection of a new tephra from the Vico volcano, central Italy, dated to 410 ± 2 ka. Our study indicates that MIS 11c (∼424-398 ka) was the warmest interval of MIS 11. The younger part of the interglacial (i.e., MIS 11b-11a; ∼398-367 ka) exhibits a gradual cooling trend passing over into MIS 10. It is characterized by considerable millennial-scale variability as inferred by six abrupt forest-contraction events. Interestingly, the first forest contraction occurred during full interglacial conditions of MIS 11c; this event lasted for ∼1.7 kyrs (406.2-404.5 ka) and was characterized by substantial reductions in winter temperature and annual precipitation. Most notably, it occurred ∼7 ka before the end of MIS 11c and ∼15 ka before the first strong ice-rafted debris event in the North Atlantic. Our findings suggest that millennial-scale climate variability during MIS 11 was established in Southern Europe already during MIS 11c, which is earlier than in the North Atlantic where it is registered only from MIS 11b onwards.

  16. Southern California climate, hydrology and vegetation over the past ~96 ka from Baldwin Lake, San Bernardino Mountains, California

    NASA Astrophysics Data System (ADS)

    Glover, K. C.; Kirby, M. E.; Rhodes, E. J.; Silveira, E.; Stevens, L. R.; Lydon, S. E.; Whitaker, A.; MacDonald, G. M.

    2015-12-01

    Continuous paleoclimate records are scarce from terrestrial sites in Southern California beyond the Last Glacial Period (i.e. Marine Isotope Stage 2, MIS 2). Baldwin Lake in the Big Bear Valley, San Bernardino Mountains (SBM), is a playa lake in the ecotone between desert and Mediterranean climate and vegetation. We recovered a 27 m core from the site in 2012, which spans ~96 - 10 ka, based upon radiocarbon dating, infrared stimulated luminescence dating, and orbital tuning. Total organic content, total carbonate content, density, magnetic susceptibility, x-ray fluorescence, and grain size data show a lake system that responded in tandem with Marine Isotope State transitions. After the basin closed during MIS 5b, Baldwin Lake was productive for MIS 5a, then cycled through an inorganic phase to a highly organic lowstand by the end of MIS 4. A stratified lake of rapidly-deposited organic silt prevailed throughout MIS 3, then shifted to an inorganic, slow sedimentation regime during MIS 2. Paleoecological data (charcoal and fossil pollen) suggest that the Valley was most prone to wildfire during climate transitions (e.g. the end of the Last Glacial Maximum, ~21 ka). Forest cover was dominated by pine for much of the basin's history, save for the dry period at the onset of MIS 2, and a greater presence of oak woodland at the beginning of MIS 3. The reduced pine cover and increased sagebrush steppe in early MIS 2 suggests a more arid landscape of sagebrush steppe c. 29 - 25 ka, before reverting to wet conditions by the LGM. Throughout MIS 5a - 2, lake organic content fluctuates in tandem with solar radiation values; a possible link between lake productivity and insolation is currently being explored with biogenic silica (BiSi) analysis. The lake was desiccated by ~10 ka, perhaps driven by increasing insolation rates at the onset of MIS 1.

  17. Limitations of the Current Microbial Identification System for Identification of Clinical Yeast Isolates

    PubMed Central

    Kellogg, James A.; Bankert, David A.; Chaturvedi, Vishnu

    1998-01-01

    The ability of the rapid, computerized Microbial Identification System (MIS; Microbial ID, Inc.) to identify a variety of clinical isolates of yeast species was compared to the abilities of a combination of tests including the Yeast Biochemical Card (bioMerieux Vitek), determination of microscopic morphology on cornmeal agar with Tween 80, and when necessary, conventional biochemical tests and/or the API 20C Aux system (bioMerieux Vitek) to identify the same yeast isolates. The MIS chromatographically analyzes cellular fatty acids and compares the results with the fatty acid profiles in its database. Yeast isolates were subcultured onto Sabouraud dextrose agar and were incubated at 28°C for 24 h. The resulting colonies were saponified, methylated, extracted, and chromatographically analyzed (by version 3.8 of the MIS YSTCLN database) according to the manufacturer’s instructions. Of 477 isolates of 23 species tested, 448 (94%) were given species names by the MIS and 29 (6%) were unidentified (specified as “no match” by the MIS). Of the 448 isolates given names by the MIS, only 335 (75%) of the identifications were correct to the species level. While the MIS correctly identified only 102 (82%) of 124 isolates of Candida glabrata, the predictive value of an MIS identification of unknown isolates as C. glabrata was 100% (102 of 102) because no isolates of other species were misidentified as C. glabrata. In contrast, while the MIS correctly identified 100% (15 of 15) of the isolates of Saccharomyces cerevisiae, the predictive value of an MIS identification of unknown isolates as S. cerevisiae was only 47% (15 of 32), because 17 isolates of C. glabrata were misidentified as S. cerevisiae. The low predictive values for accuracy associated with MIS identifications for most of the remaining yeast species indicate that the procedure and/or database for the system need to be improved. PMID:9574676

  18. AMH/MIS as a contraceptive that protects the ovarian reserve during chemotherapy

    PubMed Central

    Kano, Motohiro; Sosulski, Amanda E.; Zhang, LiHua; Saatcioglu, Hatice D.; Wang, Dan; Nagykery, Nicholas; Sabatini, Mary E.; Gao, Guangping; Donahoe, Patricia K.; Pépin, David

    2017-01-01

    The ovarian reserve represents the stock of quiescent primordial follicles in the ovary which is gradually depleted during a woman’s reproductive lifespan, resulting in menopause. Müllerian inhibiting substance (MIS) (or anti-Müllerian hormone/AMH), which is produced by granulosa cells of growing follicles, has been proposed as a negative regulator of primordial follicle activation. Here we show that long-term parenteral administration of superphysiological doses of MIS, using either an adeno-associated virus serotype 9 (AAV9) gene therapy vector or recombinant protein, resulted in a complete arrest of folliculogenesis in mice. The ovaries of MIS-treated mice were smaller than those in controls and did not contain growing follicles but retained a normal ovarian reserve. When mice treated with AAV9/MIS were paired with male breeders, they exhibited complete and permanent contraception for their entire reproductive lifespan, disrupted vaginal cycling, and hypergonadotropic hypogonadism. However, when ovaries from AAV9-MIS–treated mice were transplanted orthotopically into normal recipient mice, or when treatment with the protein was discontinued, folliculogenesis resumed, suggesting reversibility. One of the important causes of primary ovarian insufficiency is chemotherapy-induced primordial follicle depletion, which has been proposed to be mediated in part by increased activation. To test the hypothesis that MIS could prevent chemotherapy-induced overactivation, mice were given carboplatin, doxorubicin, or cyclophosphamide and were cotreated with AAV9-MIS, recombinant MIS protein, or vehicle controls. We found significantly more primordial follicles in MIS-treated animals than in controls. Thus treatment with MIS may provide a method of contraception with the unique characteristic of blocking primordial follicle activation that could be exploited to prevent the primary ovarian insufficiency often associated with chemotherapy. PMID:28137855

  19. Glacial-interglacial variations in sediment organic carbon accumulation and benthic foraminiferal assemblages on the Bermuda Rise (ODP Site 1063) during MIS 13 to 10

    NASA Astrophysics Data System (ADS)

    Poli, Maria Serena; Meyers, Philip A.; Thunell, Robert C.; Capodivacca, Marco

    2012-09-01

    We have determined organic carbon concentrations and isotopic compositions and benthic foraminiferal assemblages in sediments deposited between ˜500 and 340 ka at ODP Site 1063 on the northeastern flank of the Bermuda Rise. This time interval includes Marine Isotope Stage (MIS) 11, a particularly warm and long interglacial that was similar to today, and MIS 12, one of the most severe glacials of the last 600 kyr. During MIS 11.3, the peak of interglacial warming, organic carbon accumulation rates are low and benthic foraminiferal assemblages are dominated by Nuttallides umbonifera, a species indicative of oligotrophic environments. Higher accumulation rates during MIS 12 and 10 correspond with elevated sedimentation rates (33-36 cm/kyr). This pattern implies a combination of enhanced delivery and improved preservation of sediment organic matter during these glacial times. Organic δ13C values are less negative during MIS 12 and MIS 10 than during MIS 11, which is consistent with greater glacial-stage marine productivity. High relative abundances ofOridorsalis umbonatus during glacial intervals probably records a low but sustained flux of highly degraded organic material. Large, recurrent fluctuations in the abundance of Epistominella exiguaat the beginnings of the MIS 12 and MIS 10 glaciations suggest a marked increase in local phytoplankton blooms at these times and consequent delivery of phytodetritus to the seafloor. The most likely causes of these variations are changes in the position and strength of the Gulf Stream and its associated cold-ring eddies, combined with increased advection of terrigenous sediments from northerly locations during glacial lowstands.

  20. Climate changes in south western Iberia and Mediterranean Outflow variations during two contrasting cycles of the last 1 Myrs: MIS 31-MIS 30 and MIS 12-MIS 11

    NASA Astrophysics Data System (ADS)

    Sánchez Goñi, M. F.; Llave, E.; Oliveira, D.; Naughton, F.; Desprat, S.; Ducassou, E.; Hodell, D. A.; Hernández-Molina, F. J.

    2016-01-01

    Grain size analysis and physical properties of Sites U1388, U1389 and U1390 collected in the Contourite Depositional System of the Gulf of Cádiz during the Integrated Ocean Drilling Program (IODP) Expedition 339 "Mediterranean Outflow" reveal relative changes in bottom current strength, a tracer of the dynamics of the Mediterranean Outflow Water (MOW), before and after the Middle Pleistocene Transition (MPT). The comparison of MOW behavior with climate changes identified by the pollen analysis and δ18O benthic foraminifera measurements of Site U1385, the Shackleton Site, collected in the south western Iberian margin shows that the interval MIS 31-MIS 30, ~ 1.1-1.05 million years ago (Ma), before the MPT, was marked by wetter climate and weaker bottom current than the interval MIS 12-MIS 11 (0.47-0.39 Ma), after the MPT. Similarly, the increase in fine particles from these glacials to interglacials and in coarse fraction from interglacials to glacials was coeval with forest and semi-desert expansions, respectively, indicating the lowering/enhancement of MOW strength during periods of regional increase/decrease of moisture. While these findings may not necessarily apply to all glacial/interglacial cycles, they nonetheless serve as excellent supporting examples of the hypothesis that aridification can serve as a good tracer for MOW intensity. The strongest regional aridity during MIS 12 coincides with a remarkable increase of coarse grain size deposition and distribution that we interpret as a maximum in MOW strength. This MOW intensification may have pre-conditioned the North Atlantic by increasing salinity, thereby triggering the strong resumption of the Meridional Overturning Circulation that could contribute to the great warmth that characterizes the MIS 11c super-interglacial.

  1. The Last Interglacial-Glacial cycle (MIS 5-2) re-examined based on long proxy records from central and northern Europe

    NASA Astrophysics Data System (ADS)

    Helmens, Karin F.

    2014-02-01

    Current multi-proxy studies on a long sediment sequence preserved at Sokli (N Finland), i.e. in the central area of Fennoscandian glaciations, are drastically changing classic ideas of glaciations, vegetation and climate in northern Europe during the Late Pleistocene. The sediments in the Sokli basin have escaped major glacial erosion due to non-typical bedrock conditions. In this review, the Sokli record is compared in great detail with other long proxy records from central, temperate and northern, boreal Europe. These comprise the classic records of La Grande Pile (E France) and Oerel (N Germany) and more recently obtained records from Horoszki Duże (E Poland) and Lake Yamozero (NW Russia). The focus of the review is on pollen, lithology and macrofossil- and insect-based temperature inferences. The long records are further compared with recent proxy data from nearby terrestrial sites as well as with the rapidly accumulating high-resolution proxy data from the ocean realm. The comparison allows a re-examination of the environmental history and climate evolution of the Last Interglacial-Glacial (LI-G) cycle (MIS 5-2). It shows that environmental and climate conditions during MIS 5 (ca 130-70 ka BP) were distinctly different from those during MIS 4-2 (ca 70-15 ka BP). MIS 5 is characterized by three long forested intervals (broadly corresponding to MIS 5e, 5c, 5a), both in temperate and northern boreal Europe. These mild periods were interrupted by two short, relatively cold and dry intervals (MIS 5d and 5b) with mountain-centered glaciation in Fennoscandia. Millennial scale climate events were superimposed upon these longer lasting climate fluctuations. The time interval encompassing MIS 4-2 shows open vegetation. It is characterized by two glacial maxima (MIS 4 and 2) with sub-continental scale glaciation over northern Europe and dry conditions in strongly continental eastern European settings. High amplitude climate oscillations of millennial duration characterized the climate variability of MIS 3. Mild climate conditions in early MIS 3 caused large-scale deglaciation of the Fennoscandian Ice Sheet, and ice-free conditions with Betula-dominated vegetation (including tree birch) persisted over large parts of Fennoscandia, possibly interrupted by glaciation, during major part of MIS 3 till ca 35 ka BP. Overall, MIS 5 was mostly mild with warmest or peak interglacial conditions at the very start during MIS 5e. MIS 4-2 was mostly cold with most extreme or peak glacial conditions in the closing phase during MIS 2. This points to a subdivision of the last climate cycle into an early, overall mild interglacial half and a late, overall cold glacial half, each with duration of ca 50 ka. This review also shows that the climate variability in central and northern Europe during the LI-G cycle was mostly in degrees of continentality with major shifts in winter temperature and precipitation values; summer temperatures, on the other hand, remained largely unchanged. It points to the waxing and waning of sea-ice over the North Atlantic Ocean as a possible characteristic feature of the Late Pleistocene. The present compilation, based on long terrestrial sequences, high-resolution multi-proxy data from the oceans, and quantified paleo-climate data, strongly favors a definition of entire Marine Oxygen Isotope Stage 5 as the Last Interglacial similar as in the original marine stratigraphy and the stratigraphy at La Grande Pile in France. The proxy-based climate data places the start of the Last Glacial at the base of MIS 4 and the northwest European Pleniglacial. It shows that the division between the Eemian (MIS 5e) and the Early Weichselian (MIS 5d-a) is not useful, as not relevant from a climate point of view.

  2. Comparison of serum and plasma measurements of Müllerian inhibiting substance.

    PubMed

    Merhi, Zaher O; Messerlian, Geralyn M; Minkoff, Howard; Eklund, Elizabeth E; Macura, Jerzy; Feldman, Joseph; Rodriguez, Carlos; Seifer, David B

    2008-06-01

    The authors sought to determine whether measurement of plasma Müllerian inhibiting substance (MIS) is a suitable substitute for measurement of serum MIS. Eighteen samples of serum and plasma were examined that were drawn simultaneously. Levels of MIS were measured with an ELISA kit, and plasma levels were studied in parallel to serum samples. A 98.5% correlation was found between serum and plasma MIS values.

  3. Climatic implications of the Quaternary fluvial tufa record in the NE Iberian Peninsula over the last 500 ka

    NASA Astrophysics Data System (ADS)

    Sancho, Carlos; Arenas, Concha; Vázquez-Urbez, Marta; Pardo, Gonzalo; Lozano, María Victoria; Peña-Monné, José Luis; Hellstrom, John; Ortiz, José Eugenio; Osácar, María Cinta; Auqué, Luis; Torres, Trinidad

    2015-11-01

    The drainage area of the Iberian Ranges (NE Spain) houses one of the most extensive Quaternary fluvial tufaceous records in Europe. In this study, tufa deposits in the Añamaza, Mesa, Piedra and Ebrón river valleys were mapped, stratigraphically described and chronologically referenced from U/Th disequilibrium series, amino acid racemization and radiocarbon methods. Tufa deposits accumulated in cascades, barrage-cascades and related damming areas developed in stepped fluvial systems. The maximum frequency of tufa deposition was identified at 120 ka (Marine Oxygen Isotope Stage [MIS] 5e), 102 ka (MIS 5c), 85 ka ( MIS 5a) and 7 ka (MIS 1), probably under warmer and wetter conditions than today. Additional phases of tufa deposition appear at 353 ka ( end of MIS 11), 258-180 ka (MIS 7) and 171-154 ka (MIS 6). Although most tufa deposition episodes are clearly correlated with interstadial periods, the occurrence of tufa deposits during the penultimate glaciation (MIS 6) is remarkable, indicating that the onset of this stage was climatically favourable in the Iberian Peninsula. Biostatic conditions and the dynamics of karstic systems regulating tufa deposition seem to be sensitive to the precipitation regime, controlled by shifts in the position of North Atlantic atmospheric belts, and summer insolation, regulated by orbital forcing.

  4. Three-year postoperative outcomes between MIS and conventional TLIF in1-segment lumbar disc herniation.

    PubMed

    Lv, You; Chen, Jingyang; Chen, Jinchuan; Wu, Yuling; Chen, Xiangyang; Liu, Yi; Chu, Zhaoming; Sheng, Luxin; Qin, Rujie; Chen, Ming

    2017-06-01

    The aim of this study is to assess the long-term clinical and radiological outcomes between minimally invasive (MIS) and conventional transforaminal lumbar interbody fusion (TLIF) in treating one-segment lumbar disc herniation (LDH). One-hundred and six patients treated by MIS-TLIF (50 cases) or conventional TLIF (56 cases) were included. Perioperative results were evaluated. Clinical outcomes were compared preoperatively and postoperatively. Radiologic parameters were based on a comparison of preoperative and three-year postoperative lumbar lordosis, segmental lordosis, sacral slope, the cross-sectional area of the paraspinal muscle and fusion rates. MIS TILF had significantly less blood, shorter operation time, mean return to work time and lower intramuscular pressure compared with the conventional group during the operation. VAS scores for lower back pain and ODI in MIS-TLIF were significantly decreased. The mean cross-sectional area of the paraspinal muscle was significantly decreased after surgery in the conventional TLIF group and no significant intragroup differences were established in the MIS-TLIF group. No significant differences were found in fusion rate, lumbar lordosis, segmental lordosis and sacral slope. Both MIS and conventional TLIF were beneficial for patients with LDH. However, MIS-TLIF manifests a great improvement in perioperative outcomes, low back pain, disability and preventing paraspinal muscle atrophy during the follow-up period observation.

  5. Comparing oncologic outcomes after minimally invasive and open surgery for pediatric neuroblastoma and Wilms tumor.

    PubMed

    Ezekian, Brian; Englum, Brian R; Gulack, Brian C; Rialon, Kristy L; Kim, Jina; Talbot, Lindsay J; Adibe, Obinna O; Routh, Jonathan C; Tracy, Elisabeth T; Rice, Henry E

    2018-01-01

    Minimally invasive surgery (MIS) has been widely adopted for common operations in pediatric surgery; however, its role in childhood tumors is limited by concerns about oncologic outcomes. We compared open and MIS approaches for pediatric neuroblastoma and Wilms tumor (WT) using a national database. The National Cancer Data Base from 2010 to 2012 was queried for cases of neuroblastoma and WT in children ≤21 years old. Children were classified as receiving open or MIS surgery for definitive resection, with clinical outcomes compared using a propensity matching methodology (two open:one MIS). For children with neuroblastoma, 17% (98 of 579) underwent MIS, while only 5% of children with WT (35 of 695) had an MIS approach for tumor resection. After propensity matching, there was no difference between open and MIS surgery for either tumor for 30-day mortality, readmissions, surgical margin status, and 1- and 3-year survival. However, in both tumors, open surgery more often evaluated lymph nodes and had larger lymph node harvest. Our retrospective review suggests that the use of MIS appears to be a safe method of oncologic resection for select children with neuroblastoma and WT. Further research should clarify which children are the optimal candidates for this approach. © 2017 Wiley Periodicals, Inc.

  6. Vegetation responses to interglacial warming in the Arctic, examples from Lake El'gygytgyn, northeast Siberia

    NASA Astrophysics Data System (ADS)

    Lozhkin, A. V.; Anderson, P. M.

    2013-01-01

    Palynological data from Lake El'gygytgyn reveal responses of plant communities to a range of climatic conditions that can help assess the possible impact of global warming on arctoboreal ecosystems. Vegetation associated with climatic optima suggests two types of interglacial responses: one is dominated by deciduous taxa (the postglacial thermal maximum (PGTM) and marine isotope stage (MIS5)) and the second by evergreen conifers (MIS11, MIS31). The MIS11 forests show a similarity to Picea-Larix-Betula-Alnus forests of Siberia. While dark coniferous forest also characterizes MIS31, the pollen taxa show an affinity to the modern boreal forest of the lower Amur valley in the Russian Far East. Despite vegetation differences during the thermal maxima, all four glacial-interglacial transitions are alike, being dominated by deciduous woody taxa. Initially Betula shrub tundra established and was replaced by tundra with tree-sized shrubs (PGTM), Betula woodland (MIS5), or Betula-Larix (MIS11, MIS31) forest. The consistent occurrence of deciduous forest and/or high shrub tundra in all interglaciations as they approach or achieve maximum warmth underscores the significance of this biome for modeling efforts. The El'gygytgyn data also suggest the possible elimination or massive reduction of arctic plant communities under extreme warm-earth scenarios.

  7. Changes in detrital input, ventilation and productivity in the central Okhotsk Sea during the marine isotope stage 5e, penultimate interglacial period

    NASA Astrophysics Data System (ADS)

    Jimenez-Espejo, Francisco J.; García-Alix, Antonio; Harada, Naomi; Bahr, André; Sakai, Saburo; Iijima, Koichi; Chang, Qing; Sato, Keiko; Suzuki, Katsuhiko; Ohkouchi, Naohiko

    2018-05-01

    By presenting benthic foraminifera isotope profiles and bulk geochemical composition of core sediments, we offer a mutiproxy reconstruction of the central Okhotsk Sea oceanography between ∼130 to and ∼115 kyr, related to the marine isotopic stage 5e (MIS 5e). Sediments from the site MR0604-PC7A have been compared with paleo- sea surface temperatures and other records. This multiparameter approach allowed to recognize three periods for MIS 5e evolution, characterized by variations in marine productivity and bottom oxygenation. These variations have been ultimately associated with the production of Okhotsk Sea Intermediate Water and the presence or absence of nutrient contribution from the Pacific Deep Water into central Okhotsk Sea. Aeolian input reconstructed by Th/Sc ratio indicates higher values during the MIS 6 and MIS 5d compared with the MIS 5e. Eu∗ values indicate an input of detrital material from Kurile Islands and East-Kamchatka during the late MIS 5e, absent during the early MIS 5e and glacial periods.

  8. A perioperative cost analysis comparing single-level minimally invasive and open transforaminal lumbar interbody fusion.

    PubMed

    Singh, Kern; Nandyala, Sreeharsha V; Marquez-Lara, Alejandro; Fineberg, Steven J; Oglesby, Mathew; Pelton, Miguel A; Andersson, Gunnar B; Isayeva, Darya; Jegier, Briana J; Phillips, Frank M

    2014-08-01

    Emerging literature suggests superior clinical short- and long-term outcomes of MIS (minimally invasive surgery) TLIFs (transforaminal lumbar interbody fusion) versus open fusions. Few studies to date have analyzed the cost differences between the two techniques and their relationship to acute clinical outcomes. The purpose of the study was to determine the differences in hospitalization costs and payments for patients treated with primary single-level MIS versus open TLIF. The impact of clinical outcomes and their contribution to financial differences was explored as well. This study was a nonrandomized, nonblinded prospective review. Sixty-six consecutive patients undergoing a single-level TLIF (open/MIS) were analyzed (33 open, 33 MIS). Patients in either cohort (MIS/open) were matched based on race, sex, age, smoking status, medical comorbidities (Charlson Comorbidity index), payer, and diagnosis. Every patient in the study had a diagnosis of either degenerative disc disease or spondylolisthesis and stenosis. Operative time (minutes), length of stay (LOS, days), estimated blood loss (EBL, mL), anesthesia time (minutes), Visual Analog Scale (VAS) scores, and hospital cost/payment amount were assessed. The MIS and open TLIF groups were compared based on clinical outcomes measures and hospital cost/payment data using SPSS version 20.0 for statistical analysis. The two groups were compared using bivariate chi-squared analysis. Mann-Whitney tests were used for non-normal distributed data. Effect size estimate was calculated with the Cohen d statistic and the r statistic with a 95% confidence interval. Average surgical time was shorter for the MIS than the open TLIF group (115.8 minutes vs. 186.0 minutes respectively; p=.001). Length of stay was also reduced for the MIS versus the open group (2.3 days vs. 2.9 days, respectively; p=.018). Average anesthesia time and EBL were also lower in the MIS group (p<.001). VAS scores decreased for both groups, although these scores were significantly lower for the MIS group (p<.001). Financial analysis demonstrated lower total hospital direct costs (blood, imaging, implant, laboratory, pharmacy, physical therapy/occupational therapy/speech, room and board) in the MIS versus the open group ($19,512 vs. $23,550, p<.001). Implant costs were similar (p=.686) in both groups, although these accounted for about two-thirds of the hospital direct costs in the MIS cohort ($13,764) and half of these costs ($13,778) in the open group. Hospital payments were $6,248 higher for open TLIF patients compared with the MIS group (p=.267). MIS TLIF technique demonstrated significant reductions of operative time, LOS, anesthesia time, VAS scores, and EBL compared with the open technique. This reduction in perioperative parameters translated into lower total hospital costs over a 60-day perioperative period. Although hospital reimbursements appear higher in the open group over the MIS group, shorter surgical times and LOS days in the MIS technique provide opportunities for hospitals to reduce utilization of resources and to increase surgical case volume. Copyright © 2014 Elsevier Inc. All rights reserved.

  9. Quantitative evaluation of three advanced laparoscopic viewing technologies: a stereo endoscope, an image projection display, and a TFT display.

    PubMed

    Wentink, M; Jakimowicz, J J; Vos, L M; Meijer, D W; Wieringa, P A

    2002-08-01

    Compared to open surgery, minimally invasive surgery (MIS) relies heavily on advanced technology, such as endoscopic viewing systems and innovative instruments. The aim of the study was to objectively compare three technologically advanced laparoscopic viewing systems with the standard viewing system currently used in most Dutch hospitals. We evaluated the following advanced laparoscopic viewing systems: a Thin Film Transistor (TFT) display, a stereo endoscope, and an image projection display. The standard viewing system was comprised of a monocular endoscope and a high-resolution monitor. Task completion time served as the measure of performance. Eight surgeons with laparoscopic experience participated in the experiment. The average task time was significantly greater (p <0.05) with the stereo viewing system than with the standard viewing system. The average task times with the TFT display and the image projection display did not differ significantly from the standard viewing system. Although the stereo viewing system promises improved depth perception and the TFT and image projection displays are supposed to improve hand-eye coordination, none of these systems provided better task performance than the standard viewing system in this pelvi-trainer experiment.

  10. Cost-effectiveness of minimally invasive versus open transforaminal lumbar interbody fusion for degenerative spondylolisthesis associated low-back and leg pain over two years.

    PubMed

    Parker, Scott L; Adogwa, Owoicho; Bydon, Ali; Cheng, Joseph; McGirt, Matthew J

    2012-07-01

    Minimally invasive transforaminal lumbar interbody fusion (MIS-TLIF) for lumbar spondylolisthesis allows for surgical treatment of back and leg pain while theoretically minimizing tissue injury and accelerating overall recovery. Although the authors of previous studies have demonstrated shorter length of hospital stay and reduced blood loss with MIS versus open-TLIF, short- and long-term outcomes have been similar. No studies to date have evaluated the comprehensive health care costs associated with TLIF procedures or assessed the cost-utility of MIS- versus open-TLIF. As such, we set out to assess previously unstudied end points of health care cost and cost-utility associated with MIS- versus open-TLIF. Thirty patients undergoing MIS-TLIF (n=15) or open-TLIF (n=15) for grade I degenerative spondylolisthesis associated back and leg pain were prospectively studied. Total back-related medical resource use, missed work, and health-state values (quality-adjusted life years [QALYs], calculated from EQ-5D with U.S. valuation) were assessed after two-year follow-up. Two-year resource use was multiplied by unit costs on the basis of Medicare national allowable payment amounts (direct cost) and work-day losses were multiplied by the self-reported gross-of-tax wage rate (indirect cost). Difference in mean total cost per QALY gained for MIS- versus open-TLIF was assessed as incremental cost-effectiveness ratio (ICER: COSTmis-COSTopen/QALYmis-QALYopen). MIS versus open-TLIF cohorts were similar at baseline. By two years postoperatively, patients undergoing MIS- versus open-TLIF reported similar mean QALYs gained (0.50 vs. 0.41, P=0.17). Mean total two-year cost of MIS- and open-TLIF was $35,996 and $44,727, respectively. The $8,731 two-year cost savings of MIS- versus open-TLIF did not reach statistical significance (P=0.18) for this sample size. Although our limited sample size prevented statistical significance, MIS- versus open-TLIF was associated with reduced costs over two years while providing equivalent improvement in QALYs. MIS-TLIF allows patients to leave the hospital sooner, achieve narcotic independence sooner, and return to work sooner than open-TLIF. In our experience, MIS- versus open-TLIF is a cost reducing technology in the surgical treatment of medically refractory low-back and leg pain from grade I lumbar spondylolisthesis. Copyright © 2012 Elsevier Inc. All rights reserved.

  11. Uranium-series ages of corals, sea level history, and palaeozoogeography, Canary Islands, Spain: an exploratory study for two Quaternary interglacial periods

    USGS Publications Warehouse

    Muhs, Daniel R.; Meco, Joaquín; Simmons, Kathleen R.

    2014-01-01

    We present the first U-series ages of corals from emergent marine deposits on the Canary Islands. Deposits at + 20 m are 481 ± 39 ka, possibly correlative to marine isotope stage (or MIS) 11, while those at + 12 and + 8 m are 120.5 ± 0.8 ka and 130.2 ± 0.8 ka, respectively, correlative to MIS 5.5. The age, elevations, and uplift rates derived from MIS 5.5 deposits on the Canary Islands allow calculations of hypothetical palaeo-sea levels during the MIS 11 high sea stand. Estimates indicate that the MIS 11 high sea stand likely was at least + 9 m (relative to present sea level) and could have been as high as + 24 m. The most conservative estimates of palaeo-sea level during MIS 11 would require an ice mass loss equivalent to all of the modern Greenland and West Antarctic ice sheets; the more extreme estimates would require additional ice mass loss from the East Antarctic ice sheet. Extralimital southern species of mollusks, found in both MIS 11 and MIS 5.5 deposits on the Canary Islands, imply warmer-than-modern sea surface temperatures during at least a part of MIS 11 and much warmer sea surface temperatures during at least a part of MIS 5.5. Both MIS 11 and MIS 5.5 marine deposits on the Canary Islands contain extralimital northern species of mollusks as well, indicating cooler-than-present waters at times during these interglacial periods. We hypothesize that the co-occurrence of extralimital southern and northern species of marine invertebrates in the fossil record of the Canary Islands reflects its geographic location with respect to major synoptic-scale controls on climate and ocean currents. Previous interglacials may have been characterized by early, insolation-forced warming, along with northward migration of the intertropical convergence zone (ITCZ), accompanied by weakened trade winds and diminished upwelling. This allowed the arrival of extralimital southern taxa from the tropical Senegalese faunal province. During later parts of the MIS 11 and 5.5 interglacials, decreased insolation may have resulted in southward migration of the ITCZ, strengthened trade winds, and re-establishment of upwelling. Such conditions may have brought about not only local extinction of the Senegalese fauna, but allowed southward migration of the cooler-water Mediterranean fauna to the Canary Islands in the later parts of interglacials, a complex palaeoclimate record that is mirrored in the deep-sea core record.

  12. Comparative effectiveness of minimally invasive versus open transforaminal lumbar interbody fusion: 2-year assessment of narcotic use, return to work, disability, and quality of life.

    PubMed

    Adogwa, Owoicho; Parker, Scott L; Bydon, Ali; Cheng, Joseph; McGirt, Matthew J

    2011-12-01

    Retrospective cohort comparison between minimally invasive (MIS) and open transforaminal lumbar interbody fusion (TLIF). To assess 2 earlier unstudied endpoints (duration of narcotic use and return to work) and long-term pain, disability, and quality of life (QOL) for MIS-TLIF versus open-TLIF. MIS-TLIF for lumbar spondylolithesis theoretically allows for surgical treatment of back and leg pain while minimizing blood loss and tissue injury. Although earlier studies have shown shorter hospital stay and equivocal 6 and 24 month outcomes with MIS-TLIF versus open-TLIF, the effect of MIS techniques on postoperative narcotic use and return to work are poorly understood. Thirty patients undergoing MIS-TLIF (n = 15) or open-TLIF (n = 15) for grade I degenerative spondylolithesis-associated back and leg pain were enrolled. Two-year outcomes were assessed through phone interview and it included pain [visual analog scale (VAS)], low-back disability (Oswestry disability index), EuroQol-5D, occupational disability, and narcotic use. MIS-TLIF versus open-TLIF cohorts were similar at baseline. Median [interquartile range (IQR)] length of hospitalization after surgery was significantly less for MIS-TLIF versus open-TLIF [3 (3 to 3) vs 5.5 (4 to 6) d], P = 0.001. MIS-TLIF versus open-TLIF patients showed similar 2-year improvement in VAS for back pain, VAS for leg pain, Oswestry disability index, and EuroQol-5D scores. Overall, median (IQR) length of postoperative narcotic use was 3.0 (1.4 to 4.6) weeks and significantly shorter for MIS-TLIF versus open-TLIF patients [2.0 (1.0 to 3.0) vs 4.0 (1.4 to 4.6) wk, P = 0.008]. Overall, median (IQR) time to return to work was 13.9 (2.2 to 25.5) weeks and significantly shorter for MIS-TLIF versus open-TLIF patients [8.5 (4.4 to 21.4) vs 17.1 (1.8 to 35.9) wk, P = 0.02]. Both MIS-TLIF and open-TLIF provide long-term improvement in pain, disability, and EuroQol-5D in patients with back and leg pain from grade I degenerative spondylolithesis. However, MIS-TLIF may allow for shortened hospital stays, reduced postoperative narcotic use, and accelerated return to work, reducing both direct medical costs and indirect costs of lost work productivity associated with TLIF procedures.

  13. Various environments of interglacials recorded by Pleistocene paleosoils in Hungary (Central Europe)

    NASA Astrophysics Data System (ADS)

    Varga, György; Kis, Éva

    2015-04-01

    Based on stable isotope analyses of worldwide reference curves from deep sea, ice core and speleothem records, it has long been apparent that duration, intensity and climatic conditions of different interglacial periods were significantly diverse. As a consequence of negligible fresh, detrital material admixture during interglacials, the soil formation intensity and maturity of various kinds of past soils have been holding vital information on the environmental conditions at the time the soils formed. This, in turn, means that several physical and chemical properties of soils allow us to reconstruct past climatic regimes. Loess-paleosol sequences in Hungary (Central Europe) provide insight into the cyclic nature of glacial-interglacial variations of the last 1 million years. The paleosoils have been recognized as the product of warmer and moister interglacials, when the (glacial) loess material was altered by chemical weathering and pedogenic processes. 12 pedogene units from MIS-19 to MIS-5 strata were analysed in the course of this study, with a special attention to MIS-11 and MIS-19 periods, because of these can be regarded as analogues of the Holocene interglacial (due to the similarities in obliquity and eccentricity). Grain size, geochemical and (clay)mineralogical studies were elaborated and were gathered from previously published papers to quantify past weathering intensity and paleoenvironmental conditions by geochemical climofunctions. The Upper and partly, the Middle Pleistocene loess deposits are intercalated by steppe, forest-steppe and brown forest soils, while the older pedogene horizons are different kinds; these are red, Mediterranean-type soils. The MIS-5 pedocomplex consist of three parts at several Hungarian sites, however the pedogene units cannot be correlated unequivocally with the three MIS-5 warmer substages, due to the scarce absolute age data. The MIS-7 and MIS-9 stages are represented by three forest steppe soils. The MIS-11 pedocomplex and MIS-17 and MIS-19 units are thick and well-developed forest soils, formed under a more humid climate compared to the younger pedogene strata. The geochemical data and climofunctions have been supported well these findings. Contrary to the global loess-paleosoil sequences, the MIS-13 and MIS-15 soils are not so dominant in the Hungarian series. Support of the Hungarian Research Fund OTKA under contract PD108708 (for G. Varga) is gratefully acknowledged. It was additionally supported (for G. Varga) by the Bolyai János Research Scholarship of the Hungarian Academy of Sciences.

  14. Identifying micro-inversions using high-throughput sequencing reads.

    PubMed

    He, Feifei; Li, Yang; Tang, Yu-Hang; Ma, Jian; Zhu, Huaiqiu

    2016-01-11

    The identification of inversions of DNA segments shorter than read length (e.g., 100 bp), defined as micro-inversions (MIs), remains challenging for next-generation sequencing reads. It is acknowledged that MIs are important genomic variation and may play roles in causing genetic disease. However, current alignment methods are generally insensitive to detect MIs. Here we develop a novel tool, MID (Micro-Inversion Detector), to identify MIs in human genomes using next-generation sequencing reads. The algorithm of MID is designed based on a dynamic programming path-finding approach. What makes MID different from other variant detection tools is that MID can handle small MIs and multiple breakpoints within an unmapped read. Moreover, MID improves reliability in low coverage data by integrating multiple samples. Our evaluation demonstrated that MID outperforms Gustaf, which can currently detect inversions from 30 bp to 500 bp. To our knowledge, MID is the first method that can efficiently and reliably identify MIs from unmapped short next-generation sequencing reads. MID is reliable on low coverage data, which is suitable for large-scale projects such as the 1000 Genomes Project (1KGP). MID identified previously unknown MIs from the 1KGP that overlap with genes and regulatory elements in the human genome. We also identified MIs in cancer cell lines from Cancer Cell Line Encyclopedia (CCLE). Therefore our tool is expected to be useful to improve the study of MIs as a type of genetic variant in the human genome. The source code can be downloaded from: http://cqb.pku.edu.cn/ZhuLab/MID .

  15. When Less Is More: The indications for MIS Techniques and Separation Surgery in Metastatic Spine Disease.

    PubMed

    Zuckerman, Scott L; Laufer, Ilya; Sahgal, Arjun; Yamada, Yoshiya J; Schmidt, Meic H; Chou, Dean; Shin, John H; Kumar, Naresh; Sciubba, Daniel M

    2016-10-15

    Systematic review. The aim of this study was to review the techniques, indications, and outcomes of minimally invasive surgery (MIS) and separation surgery with subsequent radiosurgery in the treatment of patients with metastatic spine disease. The utilization of MIS techniques in patients with spine metastases is a growing area within spinal oncology. Separation surgery represents a novel paradigm where radiosurgery provides long-term control after tumor is surgically separated from the neural elements. PubMed, Embase, and CINAHL databases were systematically queried for literature reporting MIS techniques or separation surgery in patients with metastatic spine disease. PRISMA guidelines were followed. Of the initial 983 articles found, 29 met inclusion criteria. Twenty-five articles discussed MIS techniques and were grouped according to the primary objective: percutaneous stabilization (8), tubular retractors (4), mini-open approach (8), and thoracoscopy/endoscopy (5). The remaining 4 studies reported separation surgery. Indications were similar across all studies and included patients with instability, refractory pain, or neurologic compromise. Intraoperative variables, outcomes, and complications were similar in MIS studies compared to traditional approaches, and some MIS studies showed a statistically significant improvement in outcomes. Studies of mini-open techniques had the strongest evidence for superiority. Low-quality evidence currently exists for MIS techniques and separation surgery in the treatment of metastatic spine disease. Given the early promising results, the next iteration of research should include higher-quality studies with sufficient power, and will be able to provide higher-level evidence on the outcomes of MIS approaches and separation surgery. N/A.

  16. Cost-utility analysis of posterior minimally invasive fusion compared with conventional open fusion for lumbar spondylolisthesis

    PubMed Central

    Rampersaud, Y. Raja; Gray, Randolph; Lewis, Steven J.; Massicotte, Eric M.; Fehlings, Michael G.

    2011-01-01

    Background The utility and cost of minimally invasive surgical (MIS) fusion remain controversial. The primary objective of this study was to compare the direct economic impact of 1- and 2-level fusion for grade I or II degenerative or isthmic spondylolisthesis via an MIS technique compared with conventional open posterior decompression and fusion. Methods A retrospective cohort study was performed by use of prospective data from 78 consecutive patients (37 with MIS technique by 1 surgeon and 41 with open technique by 3 surgeons). Independent review of demographic, intraoperative, and acute postoperative data was performed. Oswestry disability index (ODI) and Short Form 36 (SF-36) values were prospectively collected preoperatively and at 1 year postoperatively. Cost-utility analysis was performed by use of in-hospital micro-costing data (operating room, nursing, imaging, laboratories, pharmacy, and allied health cost) and change in health utility index (SF-6D) at 1 year. Results The groups were comparable in terms of age, sex, preoperative hemoglobin, comorbidities, and body mass index. Groups significantly differed (P < .01) regarding baseline ODI and SF-6D scores, as well as number of 2-level fusions (MIS, 12; open, 20) and number of interbody cages (MIS, 45; open, 14). Blood loss (200 mL vs 798 mL), transfusions (0% vs 17%), and length of stay (LOS) (6.1 days vs 8.4 days) were significantly (P < .01) lower in the MIS group. Complications were also fewer in the MIS group (4 vs 12, P < .02). The mean cost of an open fusion was 1.28 times greater than that of an MIS fusion (P = .001). Both groups had significant improvement in 1-year outcome. The changes in ODI and SF-6D scores were not statistically different between groups. Multivariate regression analysis showed that LOS and number of levels fused were independent predictors of cost. Age and MIS were the only predictors of LOS. Baseline outcomes and MIS were predictors of 1-year outcome. Conclusion MIS posterior fusion for spondylolisthesis does reduce blood loss, transfusion requirements, and LOS. Both techniques provided substantial clinical improvements at 1 year. The cost utility of the MIS technique was considered comparable to that of the open technique. Level of Evidence Level III. PMID:25802665

  17. How Are MIS-5e And MIS-11 Different From Other Interglacials And the Future?

    NASA Astrophysics Data System (ADS)

    Yin, Q.; Berger, A.

    2017-12-01

    MIS-5e and MIS-11 appear in many proxy records as the warmest interglacials of the last million years although their astronomical configurations are very different. To investigate how they are different from other interglacials and between themselves, the climate of nine interglacials of the past 800,000 years has been simulated using both snapshot and transient experiments. These simulations allow to investigate the relative contributions of insolation and CO2 to the intensity and duration of each interglacial as well as the differences and similarities between the interglacials. The transient simulations which cover a large range of precession, obliquity and eccentricity allow to investigate the response of different climate variables and different regions to the three astronomical parameters. My presentation will focus on the characteristics of the climate forcing and response of MIS-5e and MIS-11 in comparison with the other intergalcials. Their duration and intensity at global and regional scales will be shown and the causes will be discussed. Unique features in astronomical forcing as well as in regional climate response are found in MIS-5e and MIS-11, which might help to understand why they appear to be among the warmest interglacials. The model results also show that the warm interval of MIS-11 is the longest, confirming its long duration as found in many proxy records. The long duration of MIS-11 is related to a particular combination of eccentricity, obliquity and precession as well as to its long-lasting high CO2 concentration. The differences between the seasonal behaviour of the past interglacials highlight the importance of seasonal climate reconstruction and therefore the necessity to obtain seasonal proxies. The simulated climate of MIS-5e and MIS-11 will also be compared with the climate of today and of the future to investigate the differences and similarities between the past warm conditions and the projected future warming. Part of the results are published in: Yin Q.Z. and Berger A., 2015. Interglacial analogues of the Holocene and its natural near future. Quaternary Science Reviews, 120, 28-46. Yin Q.Z. and Berger A., 2012. Individual contribution of insolation and CO2 to the interglacial climates of the past 800,000 years. Climate Dynamics 38:709-724.

  18. Training potential in minimally invasive surgery in a tertiary care, paediatric urology centre.

    PubMed

    Schroeder, R P J; Chrzan, R J; Klijn, A J; Kuijper, C F; Dik, P; de Jong, T P V M

    2015-10-01

    Minimally invasive surgery (MIS) is being utilized more frequently as a surgical technique in general surgery and in paediatric urology. It is associated with a steep learning curve. Currently, the centre does not offer a MIS training programme. It is hypothesized that the number of MIS procedures performed in the low-volume specialty of paediatric urology will offer insufficient training potential for surgeons. To assess the MIS training potential of a highly specialized, tertiary care, paediatric urology training centre that has been accredited by the Joint Committee of Paediatric Urology (JCPU). The clinical activity of the department was retrospectively reviewed by extracting the annual number of admissions, outpatient consultations and operative procedures. The operations were divided into open procedures and MIS. Major ablative procedures (nephrectomy) and reconstructive procedures (pyeloplasty) were analysed with reference to the patients' ages. The centre policy is not to perform major MIS in children who are under 2 years old or who weigh less than 12 kg. Every year, this institution provides approximately 4300 out-patient consultations, 600 admissions, and 1300 procedures under general anaesthesia for children with urological problems. In 2012, 35 patients underwent major intricate MIS: 16 pyeloplasties, eight nephrectomies and 11 operations for incontinence (seven Burch, and four bladder neck procedures). In children ≥2 years of age, 16/21 of the pyeloplasties and 8/12 of the nephrectomies were performed laparoscopically. The remaining MIS procedures included 25 orchidopexies and one intravesical ureteral reimplantation. There is no consensus on how to assess laparoscopic training. It would be valuable to reach a consensus on a standardized laparoscopic training programme in paediatric urology. Often training potential is based on operation numbers only. In paediatric urology no minimum requirement has been specified. The number of procedures quoted for proficiency in MIS remains controversial. The MIS numbers for this centre correspond to, or exceed, numbers mentioned in other literature. To provide high-quality MIS training, exposure to laparoscopic procedures should be expanded. This may be achieved by centralizing patients into a common centre, collaborating with other specialities, modular training and training outside the operating theatre. Even in a high-volume, paediatric urology educational centre, the number of major MIS procedures performed remains relatively low, leading to limited training potential. Copyright © 2015. Published by Elsevier Ltd.

  19. Minimally invasive and computer-navigated total hip arthroplasty: a qualitative and systematic review of the literature

    PubMed Central

    2010-01-01

    Background Both minimally invasive surgery (MIS) and computer-assisted surgery (CAS) for total hip arthroplasty (THA) have gained popularity in recent years. We conducted a qualitative and systematic review to assess the effectiveness of MIS, CAS and computer-assisted MIS for THA. Methods An extensive computerised literature search of PubMed, Medline, Embase and OVIDSP was conducted. Both randomised clinical trials and controlled clinical trials on the effectiveness of MIS, CAS and computer-assisted MIS for THA were included. Methodological quality was independently assessed by two reviewers. Effect estimates were calculated and a best-evidence synthesis was performed. Results Four high-quality and 14 medium-quality studies with MIS THA as study contrast, and three high-quality and four medium-quality studies with CAS THA as study contrast were included. No studies with computer-assisted MIS for THA as study contrast were identified. Strong evidence was found for a decrease in operative time and intraoperative blood loss for MIS THA, with no difference in complication rates and risk for acetabular outliers. Strong evidence exists that there is no difference in physical functioning, measured either by questionnaires or by gait analysis. Moderate evidence was found for a shorter length of hospital stay after MIS THA. Conflicting evidence was found for a positive effect of MIS THA on pain in the early postoperative period, but that effect diminished after three months postoperatively. Strong evidence was found for an increase in operative time for CAS THA, and limited evidence was found for a decrease in intraoperative blood loss. Furthermore, strong evidence was found for no difference in complication rates, as well as for a significantly lower risk for acetabular outliers. Conclusions The results indicate that MIS THA is a safe surgical procedure, without increases in operative time, blood loss, operative complication rates and component malposition rates. However, the beneficial effect of MIS THA on functional recovery has to be proven. The results also indicate that CAS THA, though resulting in an increase in operative time, may have a positive effect on operative blood loss and operative complication rates. More importantly, the use of CAS results in better positioning of acetabular component of the prosthesis. PMID:20470443

  20. A Methodology for Successful MIS Projects

    PubMed Central

    Jacobs, Patt

    1988-01-01

    St. Vincent Hospital and Medical Center (SVHMC) was one of the Pacific Northwests' first hospitals to install a Medical Information System (MIS). In mid 1985 the hospital was confronted with the fact that vendor support of its MIS would be withdrawn in the near future. In 21 months a complete, fully operational MIS had to be selected, installed, and implemented. MIS projects are large, complicated sets of interrelated tasks organized to achieve a specific goal for an organization. Project management requires a sound methodology to deliver proper and necessary functions, on time, within budget, and that meet user expectations. This paper focuses on the process used to deliver the SIMON System on time and 15% under budget.

  1. Radiation-hardened transistor and integrated circuit

    DOEpatents

    Ma, Kwok K.

    2007-11-20

    A composite transistor is disclosed for use in radiation hardening a CMOS IC formed on an SOI or bulk semiconductor substrate. The composite transistor has a circuit transistor and a blocking transistor connected in series with a common gate connection. A body terminal of the blocking transistor is connected only to a source terminal thereof, and to no other connection point. The blocking transistor acts to prevent a single-event transient (SET) occurring in the circuit transistor from being coupled outside the composite transistor. Similarly, when a SET occurs in the blocking transistor, the circuit transistor prevents the SET from being coupled outside the composite transistor. N-type and P-type composite transistors can be used for each and every transistor in the CMOS IC to radiation harden the IC, and can be used to form inverters and transmission gates which are the building blocks of CMOS ICs.

  2. Did the Laurentide ice sheet survive through Marine Isotope Stage 9?

    NASA Astrophysics Data System (ADS)

    Carlson, A. E.; Tarasov, L.; Ullman, D. J.

    2016-12-01

    Looking at the global benthic oxygen isotope stack, only marine oxygen isotope stage (MIS) 7 stands out as an anomalous interglaciation with a higher oxygen isotope value than other interglaciations of the last half million years. However, benthic oxygen isotopes are an integrator of global ice volume plus temperature, and records of local ice-sheet change are needed to partition the sources of the global signal. Here we use the Laurentide ice-sheet (LIS) proximal record of IODP Site U1302/1303 off of Orphan Knoll to test LIS presence/absence on the eastern Canadian shield. Ice-sheet model calibrated Si relative to Sr is low in most interglaciations of the last 500 ka reflecting the removal of the LIS and its erosive power from the Canadian Shield. However, like MIS 7, MIS 9 has continued elevated inputs of Si. Furthermore, planktic oxygen isotopes do not decrease to full interglacial levels like in MIS 1, 5e and 11. MIS 9 had a similar orbital forcing as MIS 5e, but a much shorter period of elevated interglacial carbon dioxide concentration. Based on climate model simulations of LIS stability, we suggest that the reduced period of elevated atmospheric carbon dioxide allowed the LIS to survive through MIS 9 (like MIS 7), providing important constraints for the climatic thresholds necessary for a full interglaciation.

  3. The use of Mohs micrographic surgery (MMS) for melanoma in situ (MIS) of the trunk and proximal extremities.

    PubMed

    Stigall, Landon E; Brodland, David G; Zitelli, John A

    2016-11-01

    Evaluation of the entire surgical margin results in high rates of complete excision, low local recurrence rates, and maximal tissue conservation. Although well recognized for melanoma of the head and neck, few studies have focused exclusively on the trunk and proximal extremities. We sought to evaluate the efficacy of Mohs micrographic surgery for melanoma in situ (MIS) of the trunk and proximal extremities, and determine adequate excision margins for MIS when total margin evaluation is not used. Long-term outcomes in 882 cases of MIS treated with Mohs micrographic surgery were analyzed and compared with historical controls. Rates of complete excision were determined for increasing surgical margin intervals. One local recurrence occurred in our cohort (0.1%). Only 83% of MIS were excised with a 6-mm margin. Margins of 9 mm were needed to excise 97% of MIS, statistically equivalent to thin melanomas. We used a nonrandomized, single-institution, retrospective design. Mohs micrographic surgery may cure the 17% of MIS that exceed traditional excision margins of 5 mm and is a valuable option for these patients. Surgical margins of at least 0.9 cm should be considered for MIS of the trunk and extremities when total margin evaluation is not used. Copyright © 2016 American Academy of Dermatology, Inc. Published by Elsevier Inc. All rights reserved.

  4. Mis-specified cells die by an active gene-directed process, and inhibition of this death results in cell fate transformation in Drosophila

    PubMed Central

    Werz, Christian; Lee, Tom V.; Lee, Peter L.; Lackey, Melinda; Bolduc, Clare; Stein, David S.; Bergmann, Andreas

    2009-01-01

    Summary Incorrectly specified or mis-specified cells often undergo cell death or are transformed to adopt a different cell fate during development. The underlying cause for this distinction is largely unknown. In many developmental mutants in Drosophila, large numbers of mis-specified cells die synchronously, providing a convenient model for analysis of this phenomenon. The maternal mutant bicoid is particularly useful model with which to address this issue because its mutant phenotype is a combination of both transformation of tissue (acron to telson) and cell death in the presumptive head and thorax regions. We show that a subset of these mis-specified cells die through an active gene-directed process involving transcriptional upregulation of the cell death inducer hid. Upregulation of hid also occurs in oskar mutants and other segmentation mutants. In hid bicoid double mutants, mis-specified cells in the presumptive head and thorax survive and continue to develop, but they are transformed to adopt a different cell fate. We provide evidence that the terminal torso signaling pathway protects the mis-specified telson tissue in bicoid mutants from hid-induced cell death, whereas mis-specified cells in the head and thorax die, presumably because equivalent survival signals are lacking. These data support a model whereby mis-specification can be tolerated if a survival pathway is provided, resulting in cellular transformation. PMID:16280349

  5. Quantitative reconstruction of precipitation and runoff during MIS 5a, MIS 3a, and Holocene, arid China

    NASA Astrophysics Data System (ADS)

    Liu, Yuan; Li, Yu

    2017-11-01

    Marine oxygen isotope stage 5a (MIS 5a), MIS 3a, and Holocene were highlighted periods in paleoclimate studies. Many scientists have published a great number of studies in this regard, but they paid more attention to qualitative research, and there was often a lack of quantitative data. In this paper, based on chronological evidence from a paleolake in arid China, MIS 5a, MIS 3a, and Holocene lake area, the precipitation of the drainage area and the runoff of the inflowing rivers of the lake were reconstructed with ArcGIS spatial analysis software and the improved water and energy balance model which was calibrated by modern meteorological and hydrological data in the Shiyang River drainage basin. The results showed that the paleolake areas were 1824, 1124, and 628 km2 for MIS 5a, MIS 3a, and Holocene; meanwhile, the paleoprecipitation and runoff were 293.992-297.433, 271.105-274.294, and 249.431-252.373 mm and 29.103 × 108-29.496 × 108, 18.810 × 108-18.959 × 108, and 10.637 × 108-10.777 × 108 mm, respectively. The quantitative data can help us not only strengthen the understanding of paleoclimatic characteristics but also recognize the complexity and diversity of the climate system.

  6. A comparison of registration errors with imageless computer navigation during MIS total knee arthroplasty versus standard incision total knee arthroplasty: a cadaveric study.

    PubMed

    Davis, Edward T; Pagkalos, Joseph; Gallie, Price A M; Macgroarty, Kelly; Waddell, James P; Schemitsch, Emil H

    2015-01-01

    Optimal component alignment in total knee arthroplasty has been associated with better functional outcome as well as improved implant longevity. The ability to align components optimally during minimally invasive (MIS) total knee replacement (TKR) has been a cause of concern. Computer navigation is a useful aid in achieving the desired alignment although it is limited by the error during the manual registration of landmarks. Our study aims to compare the registration process error between a standard and a MIS surgical approach. We hypothesized that performing the registration error via an MIS approach would increase the registration process error. Five fresh frozen lower limbs were routinely prepared and draped. The registration process was performed through an MIS approach. This was then extended to the standard approach and the registration was performed again. Two surgeons performed the registration process five times with each approach. Performing the registration process through the MIS approach was not associated with higher error compared to the standard approach in the alignment parameters of interest. This rejects our hypothesis. Image-free navigated MIS TKR does not appear to carry higher risk of component malalignment due to the registration process error. Navigation can be used during MIS TKR to improve alignment without reduced accuracy due to the approach.

  7. Mis16 Independently Recognizes Histone H4 and the CENP-ACnp1-Specific Chaperone Scm3sp

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    An, Sojin; Kim, Hanseong; Cho, Uhn-Soo

    2015-09-04

    CENP-A is a centromere-specific histone H3 variant that is required for kinetochore assembly and accurate chromosome segregation. For it to function properly, CENP-A must be specifically localized to centromeres. In fission yeast, Scm3sp and the Mis18 complex, composed of Mis16, Eic1, and Mis18, function as a CENP-ACnp1-specific chaperone and a recruiting factor, respectively, and together ensure accurate delivery of CENP-ACnp1 to centromeres. Although how Scm3sp specifically recognizes CENP-ACnp1 has been revealed recently, the recruiting mechanism of CENP-ACnp1 via the Mis18 complex remains unknown. In this study, we have determined crystal structures of Schizosaccharomyces japonicus Mis16 alone and in complex withmore » the helix 1 of histone H4 (H4α1). Crystal structures followed by mutant analysis and affinity pull-downs have revealed that Mis16 recognizes both H4α1 and Scm3sp independently within the CENP-ACnp1/H4:Scm3sp complex. This observation suggests that Mis16 gains CENP-ACnp1 specificity by recognizing both Scm3sp and histone H4. Our studies provide insights into the molecular mechanisms underlying specific recruitment of CENP-ACnp1/H4:Scm3sp into centromeres.« less

  8. Insights into Penultimate Interglacial-Glacial Climate Change on Vegetation History at Lake Van, Turkey

    NASA Astrophysics Data System (ADS)

    Pickarski, N.; Litt, T.

    2017-12-01

    A new detailed pollen and oxygen isotope record of the penultimate interglacial-glacial cycle (ca. 250-129 ka; MIS 7-6), has been generated from the sediment core at Lake Van, Turkey. The integration of all available proxies (pollen, microscopic charcoal, δ18Obulk, and XRF) shows three temperate intervals of high effective soil moisture availability. This is evidenced by the predominance of oak steppe-forested landscapes similar to the present interglacial vegetation in this sensitive semiarid region. The wettest/warmest stage, as indicated by highest temperate tree percentages, can be broadly correlated with MIS 7c, while the amplitude of the tree population maximum during the oldest penultimate interglacial (MIS 7e) appears to be reduced due to warm but drier climatic conditions. A detailed comparison of the penultimate interglacial complex (MIS 7) to the last interglacial (MIS 5e) and the current interglacial (MIS 1) provides a vivid illustration of possible differences in the successive climatic cycles. Intervening periods of treeless vegetation (MIS 7d, 7a) were predominated by steppe elements. The occurrence of Artemisia and Chenopodiaceae during MIS 7d indicates very dry and cold climatic conditions, while higher temperate tree percentages (mainly deciduous Quercus) points to relatively humid and mild conditions throughout MIS 7b. Despite the general dominance of dry and cold desert-steppe vegetation during the penultimate glacial (MIS 6), this period can be divided into two parts: an early stage (ca. 193-157 ka) with higher oscillations in tree percentages and a later stage (ca. 157-131 ka) with lower tree percentages and subdued oscillations. Furthermore, we are able to identify the MIS 6e event (ca. 179-159 ka), which reveals clear climate variability due to rapid alternation in the vegetation cover. In comparison with long European pollen archives, speleothem isotope records from the Near East, and global climate parameters, the new high-resolution record presents an improved insight into regional vegetation dynamics and climate variability in the eastern Mediterranean region.

  9. Phytoplankton assemblages and lipid biomarkers indicate sea-surface warming and sea-ice decline in the Ross Sea during Marine Isotope sub-Stage 5e

    NASA Astrophysics Data System (ADS)

    Hartman, Julian D.; Sangiorgi, Francesca; Peterse, Francien; Barcena, Maria A.; Albertazzi, Sonia; Asioli, Alessandra; Giglio, Federico; Langone, Leonardo; Tateo, Fabio; Trincardi, Fabio

    2016-04-01

    The Marine Isotope sub-Stage 5e (~ 125 - 119 kyrs BP), the last interglacial period before the present, is believed to have been globally warmer (~ 2°C) than today. Studying this time interval might therefore provide insights into near future climate state given the ongoing climate change and global temperature increase. Of particular interest are the expected changes in polar ice cover. One important aspect of the cryosphere is sea-ice, which influences albedo, deep and surface water currents, and phytoplankton production, and thus affects the global climate system. To investigate whether changes in sea-ice cover occurred in the Southern Ocean close to Antarctica during Marine Isotope sub-Stage 5e dinoflagellate and diatom assemblages have been analyzed in core AS05-10, drilled in the continental slope off the Drygalski basin (Ross Sea) at a water depth of 2377 m. The core was drilled within the frame of the PNRA 2009/A2.01 project, an Italian project with a multidisciplinary approach, and covers the interval from Present to Marine Isotope Stage (MIS) 7. The core stratigraphy is based on diatom bioevents and on the climate cyclicity provided by the variations of the diatom assemblages. For this study we focused on the interval from MIS7 to MIS5. A strong reduction of sea-ice-loving diatom taxa with respect to open water-loving diatom taxa is observed during MIS5. In general the production of phytoplankton increases at the base of MIS5 and then slowly decreases. Dinoflagellate cysts, particularly heterotrophic species, are abundant during MIS5e only. The sea surface temperature reconstruction based on the TEX86L, a proxy based on lipid biomarkers produced by Thaumarcheota, shows a 4°C temperature increase from MIS6 to MIS5e. A slightly smaller temperature increase is observed at the onset of MIS7, but this stage is barren of heterotrophic dinoflagellates. All proxies together seem to indicate that the retreat of the summer sea-ice in the Ross Sea during MIS5e was likely greater than that during MIS7.

  10. Additional Contribution of the Malnutrition-Inflammation Score to Predict Mortality and Patient-Reported Outcomes as Compared With Its Components in a Cohort of African Descent Hemodialysis Patients.

    PubMed

    Lopes, Marcelo Barreto; Silva, Luciana Ferreira; Lopes, Gildete Barreto; Penalva, Maria Auxiliadora; Matos, Cacia Mendes; Robinson, Bruce M; Lopes, Antonio Alberto

    2017-01-01

    The malnutrition-inflammation score (MIS) combines ten components to assess nutritional status. Higher MIS has been associated with higher mortality and poorer health-related quality of life (HRQOL) in maintenance hemodialysis (MHD) patients. It is interesting to investigate associations of each component with mortality and patient-reported outcomes (PROs), that is, HRQOL and depression symptoms, and if MIS associations are generalizable for diverse populations. This study assessed associations of MIS and its components with mortality and PROs in an African descent MHD population. Prospective cohort for mortality and cross-sectional design for PROs using data of the Prospective Study of the Prognosis of Chronic Hemodialysis Patients (PROHEMO). A total of 632 MHD patients (92% black or mixed race) treated in Salvador, Brazil. MIS (range: 0-30, higher worse) and each of its ten components (range: 0-4, higher worse). Mortality, HRQOL using the KDQOL-SF, and depression symptoms using the 20-item Center for Epidemiological Studies Depression Scale. Linear regression for comparing scores and Cox regression for mortality. After extensive adjustments, MIS ≥6 was associated with 52% higher mortality (hazard ratio = 1.52; 95% confidence interval = 1.13-2.05), higher depression symptoms, and poorer HRQOL, including physical, mental, and kidney disease-targeted HRQOL measures. Weight change, comorbidity, muscle wasting, and albumin were the MIS components indicating associations between poor nutrition and higher mortality. By contrast, gastrointestinal symptoms and functional capacity were the MIS components denoting detrimental associations of poorer nutritional status with PROs. Causal conclusions are not possible. The PROHEMO results indicate that MIS components associated with mortality are not the same associated with PROs. However, the MIS showed consistent associations with mortality and PROs. These results in a population that were not the target of previous investigations, add support for using tools combining nutritional components, such as MIS, to predict outcomes in MHD populations. Copyright © 2016 National Kidney Foundation, Inc. Published by Elsevier Inc. All rights reserved.

  11. In Vivo Anti-Herpes Simplex Virus Activity of a Sulfated Derivative of Agaricus brasiliensis Mycelial Polysaccharide

    PubMed Central

    Cardozo, F. T. G. S.; Larsen, I. V.; Carballo, E. V.; Jose, G.; Stern, R. A.; Brummel, R. C.; Camelini, C. M.; Rossi, M. J.; Simões, C. M. O.

    2013-01-01

    Agaricus brasiliensis (syn. A. subrufescens), a basidiomycete fungus native to the Atlantic forest in Brazil, contains cell walls rich in glucomannan polysaccharides. The β-(1→2)-gluco-β-(1→3)-mannan was isolated from A. brasiliensis mycelium, chemically modified by sulfation, and named MI-S. MI-S has multiple mechanisms of action, including inhibition of herpes simplex virus (HSV) attachment, entry, and cell-to-cell spread (F. T. G. S. Cardozo, C. M. Camelini, A. Mascarello, M. J. Rossi, R. J. Nunes, C. R. Barardi, M. M. de Mendonça, and C. M. O. Simões, Antiviral Res. 92:108–114, 2011). The antiherpetic efficacy of MI-S was assessed in murine ocular, cutaneous, and genital infection models of HSV. Groups of 10 mice were infected with HSV-1 (strain KOS) or HSV-2 (strain 333). MI-S was given either topically or by oral gavage under various pre- and posttreatment regimens, and the severity of disease and viral titers in ocular and vaginal samples were determined. No toxicity was observed in the uninfected groups treated with MI-S. The topical and oral treatments with MI-S were not effective in reducing ocular disease. Topical application of MI-S on skin lesions was also not effective, but cutaneously infected mice treated orally with MI-S had significantly reduced disease scores (P < 0.05) after day 9, suggesting that healing was accelerated. Vaginal administration of MI-S 20 min before viral challenge reduced the mean disease scores on days 5 to 9 (P < 0.05), viral titers on day 1 (P < 0.05), and mortality (P < 0.0001) in comparison to the control groups (untreated and vehicle treated). These results show that MI-S may be useful as an oral agent to reduce the severity of HSV cutaneous and mucosal lesions and, more importantly, as a microbicide to block sexual transmission of HSV-2 genital infections. PMID:23507287

  12. Revisiting Tectonic Corrections Applied to Pleistocene Sea-Level Highstands

    NASA Astrophysics Data System (ADS)

    Creveling, J. R.; Mitrovica, J. X.; Hay, C.; Austermann, J.; Kopp, R. E.

    2015-12-01

    The robustness of stratigraphic- and geomorphic-based inferences of Quaternary peak interglacial sea levels — and equivalent minimum continental ice volumes — depends on the accuracy with which highstand markers can be corrected for vertical tectonic displacement. For sites that preserve a Marine Isotope Stage (MIS) 5e sea-level highstand marker, the customary method for estimating tectonic uplift/subsidence rate computes the difference between the local elevation of the highstand marker and a reference eustatic (i.e., global mean) MIS 5e sea-level height, typically assumed to be +6 m, and then divides this height difference by the age of the highstand marker. This rate is then applied to correct the elevation of other observed sea-level markers at that site for tectonic displacement. Subtracting a reference eustatic value from a local MIS 5e highstand marker elevation introduces two potentially significant errors. First, the commonly adopted peak eustatic MIS 5e sea-level value (i.e., +6 m) is likely too low; recent studies concluded that MIS 5e peak eustatic sea level was ~6-9 m. Second, local peak MIS 5e sea level was not globally uniform, but instead characterized by significant departures from eustasy due to glacial isostatic adjustment (GIA) in response to successive glacial-interglacial cycles and excess polar ice-sheet melt relative to present day. We present numerical models of GIA that incorporate both of these effects in order to quantify the plausible range in error of previous tectonic corrections. We demonstrate that, even far from melting ice sheets, local peak MIS 5e sea level may have departed from eustasy by 2-4 m, or more. Thus, adopting an assumed reference eustatic value to estimate tectonic displacement, rather than a site-specific GIA signal, can introduce significant error in estimates of peak eustatic sea level (and minimum ice volumes) during Quaternary highstands (e.g., MIS 11, MIS 5c and MIS 5a).

  13. Interoperative efficiency in minimally invasive surgery suites.

    PubMed

    van Det, M J; Meijerink, W J H J; Hoff, C; Pierie, J P E N

    2009-10-01

    Performing minimally invasive surgery (MIS) in a conventional operating room (OR) requires additional specialized equipment otherwise stored outside the OR. Before the procedure, the OR team must collect, prepare, and connect the equipment, then take it away afterward. These extra tasks pose a thread to OR efficiency and may lengthen turnover times. The dedicated MIS suite has permanently installed laparoscopic equipment that is operational on demand. This study presents two experiments that quantify the superior efficiency of the MIS suite in the interoperative period. Preoperative setup and postoperative breakdown times in the conventional OR and the MIS suite in an experimental setting and in daily practice were analyzed. In the experimental setting, randomly chosen OR teams simulated the setup and breakdown for a standard laparoscopic cholecystectomy (LC) and a complex laparoscopic sigmoid resection (LS). In the clinical setting, the interoperative period for 66 LCs randomly assigned to the conventional OR or the MIS suite were analyzed. In the experimental setting, the setup and breakdown times were significantly shorter in the MIS suite. The difference between the two types of OR increased for the complex procedure: 2:41 min for the LC (p < 0.001) and 10:47 min for the LS (p < 0.001). In the clinical setting, the setup and breakdown times as a whole were not reduced in the MIS suite. Laparoscopic setup and breakdown times were significantly shorter in the MIS suite (mean difference, 5:39 min; p < 0.001). Efficiency during the interoperative period is significantly improved in the MIS suite. The OR nurses' tasks are relieved, which may reduce mental and physical workload and improve job satisfaction and patient safety. Due to simultaneous tasks of other disciplines, an overall turnover time reduction could not be achieved.

  14. Coal-mining seismicity and ground-shaking hazard: A case study in the Trail Mountain area, Emery County, Utah

    USGS Publications Warehouse

    Arabasz, W.J.; Nava, S.J.; McCarter, M.K.; Pankow, K.L.; Pechmann, J.C.; Ake, J.; McGarr, A.

    2005-01-01

    We describe a multipart study to quantify the potential ground-shaking hazard to Joes Valley Dam, a 58-m-high earthfill dam, posed by mining-induced seismicity (MIS) from future underground coal mining, which could approach as close as ???1 km to the dam. To characterize future MIS close to the dam, we studied MIS located ???3-7 km from the dam at the Trail Mountain coal mine. A 12-station local seismic network (11 stations above ground, one below, combining eight triaxial accelerometers and varied velocity sensors) was operated in the Trail Mountain area from late 2000 through mid-2001 for the dual purpose of (1) continuously monitoring and locating MIS associated with longwall mining at a depth of 0.5-0.6 km and (2) recording high-quality data to develop ground-motion prediction equations for the shallow MIS. (Ground-motion attenuation relationships and moment-tensor results are reported in companion articles.) Utilizing a data set of 1913 earthquakes (M ??? 2.2), we describe space-time-magnitude distributions of the observed MIS and source-mechanism information. The MIS was highly correlated with mining activity both in space and time. Most of the better-located events have depths constrained within ??0.6 km of mine level. For the preponderance (98%) of the 1913 located events, only dilatational P-wave first motions were observed, consistent with other evidence for implosive or collapse-type mechanisms associated with coal mining in this region. We assess a probable maximum magnitude of M 3.9 (84th percentile of a cumulative distribution) for potential MIS close to Joes Valley Dam based on both the worldwide and regional record of coal-mining-related MIS and the local geology and future mining scenarios.

  15. A climate model study of an intense Asian Monsoon in a La Niña-like climate of MIS-13

    NASA Astrophysics Data System (ADS)

    Karami, M. P.; Berger, A.; Herold, N.; Yin, Q. Z.

    2012-04-01

    Studying the paleo-monsoon during past interglacials is a valuable approach to improve our understanding of the monsoon system in present-day and future climates. We focus on Marine Isotopic stage 13 (MIS-13; ~0.5 Ma) which was a relatively cool interglacial, but with a paradoxically intense monsoonal precipitation over eastern and southern Asia. Our main goal is to understand the physics-based mechanism driving the intense monsoon, specifically the East Asian Summer Monsoon (EASM), during MIS-13. We applied both an intermediate complexity model (LOVECLIM) as well as fully coupled general circulation models (HadCM3 and CCSM3) to simulate pre-industrial and MIS-13 climates. The boundary conditions for MIS-13 were chosen for 506 ka with Northern-Hemisphere (NH) summer at perihelion and a CO2 concentration of 240 ppm. For pre-industrial, NH-winter occurring at perihelion and a CO2 concentration of 280 ppm were prescribed. Preliminary analysis of the model results shows different atmospheric and oceanic features in MIS-13 compared to the pre-industrial which could affect the EASM. The Northern Pacific Subtropical High (NPSH), which is an important factor in controlling the EASM, strengthened and extended to the northwest in MIS-13 partially due to cooling of the central Pacific Ocean. This in turn brought more moisture from the Central Pacific to the EASM-region and caused a northwestward shift and bending of the low-level jet along East Asia. The change in the low-level jet subsequently increased the meridional wind velocity at 850 mbar in the EASM-region providing more moisture from the tropical Pacific and Indian Oceans. In addition, higher sea-surface temperature in the Indian Ocean during MIS-13 further increased the source of moisture for the EASM. The Asian low, which is another component of the EASM-system, also shifted eastward moving the rain band northward. Moreover, it was found that MIS-13 had a dominant La Niña condition in the tropical Pacific. La Niña-type climate is normally expected to favor increases in precipitation in the EASM through the NPSH as can be seen in MIS-13. Whether there was ENSO variability around the La Niña-like background climatic state of MIS-13 or not is under further investigation. The correlation between the sea-surface temperature variability in the tropical Pacific and the EASM precipitation was found to increase in MIS-13 compared to the pre-industrial which is another factor explaining the intensified EASM in MIS13. Although our model results show high precipitation for MIS-13 qualitatively consistent with data, we are still interested in other factors that could increase the precipitation even further. *This work is supported by the European Research Council Advanced Grant EMIS (No 227348 of the Programme 'ideas')

  16. Mouse chromosomal mapping of a murine leukemia virus integration region (Mis-1) first identified in rat thymic leukemia.

    PubMed Central

    Jolicoeur, P; Villeneuve, L; Rassart, E; Kozak, C

    1985-01-01

    We have previously identified a region of genomic DNA which constitutes the site of frequent provirus integration in rat thymomas induced by Moloney murine leukemia virus (Lemay and Jolicoeur, Proc. Natl. Acad. Sci. USA 81:38-42, 1984). This genetic locus is now designated Mis-1 (Moloney integration site). Cellular sequences homologous to Mis-1 are present in mouse DNA. Using a series of hamster-mouse somatic cell hybrids, we mapped the Mis-1 locus to mouse chromosome 15. Frequent chromosome 15 aberrations have been described in mouse thymomas. Mis-1 represents a putative new oncogene which might be involved in the initiation or maintenance or both of these neoplasms. Images PMID:4068142

  17. MIS On-Line.

    ERIC Educational Resources Information Center

    Thomson, Nancy S.; Echeverria, Donna Rose; Mills, Bob

    This paper describes the resources, processes and outcomes involved in the development of an introductory Management Information Systems (MIS) course designed to utilize as many of the technologies as possible to redefine the teaching/learning paradigm. The MIS-Online project at Northwest Missouri State University encompasses the available campus…

  18. ELPIDA: a general architecture for medical imaging systems supporting telemedicine applications

    NASA Astrophysics Data System (ADS)

    Lymberopoulos, Dimitris C.; Spiropoulos, Kostas V.; Anastassopoulos, George C.; Kotsopoulos, Stavros A.; Solomou, Katerina G.

    1995-01-01

    During the next years, profound changes are expected in computer and communication technologies that will offer the medical imaging systems (MIS) industry a challenge to develop advanced telemedicine applications of high performance. Medical industry, vendors, and specialists need to agree on a universal MIS structure that will provide a stack of functions, protocols, and interfaces suitable for coordination and management of high-level image consults, reports, and review activities. Doctors and engineers have worked together to determine the types, targets, and range of such activities within a medical group working domain and to posit their impact on MIS structure. As a result, the fundamental MIS functions have been posed and organized in the form of a general MIS architecture, denoted as ELPIDA. The structure of this architecture was kept as simple as possible to allow its extension to diverse multimode operational schemes handling medical and conversational audiovisual information of different classes. The fundamentals of ELPIDA and pulmonary image diagnostic aspects have been employed for the development of a prototype MIS.

  19. Reassessing the penultimate interglacial analog for current climate change, evidence from Antarctic dust

    NASA Astrophysics Data System (ADS)

    Aarons, S. M.; Aciego, S.; McConnell, J.

    2017-12-01

    Dust emissions and transport are linked to spatial and temporal climate variability, with dust provenance providing clues to past climate and climate impacts. The penultimate interglacial period (MIS 5e) has been suggested as an analog to Holocene climate change. We present the first evaluation of the MIS 5e ice archive developed at Taylor Glacier, East Antarctica and provide a record of dust transported to Taylor Glacier during MIS 5e. Our record shows significant differences between MIS 5e, Holocene, and pre-industrial dust transported to East Antarctica. The MIS 5e dust is sourced from New Zealand and southern South America (SSA), while the Holocene dust is sourced from local Antarctic, SSA, and potentially Australian sources. This profound change in composition suggests a variation in atmospheric transport pathways and/or paleo-environmental conditions between the interglacial periods, and indicates that MIS 5e should be reassessed as an analog for climate change and associated impacts.

  20. Non-random Mis-segregation of Human Chromosomes.

    PubMed

    Worrall, Joseph Thomas; Tamura, Naoka; Mazzagatti, Alice; Shaikh, Nadeem; van Lingen, Tineke; Bakker, Bjorn; Spierings, Diana Carolina Johanna; Vladimirou, Elina; Foijer, Floris; McClelland, Sarah Elizabeth

    2018-06-12

    A common assumption is that human chromosomes carry equal chances of mis-segregation during compromised cell division. Human chromosomes vary in multiple parameters that might generate bias, but technological limitations have precluded a comprehensive analysis of chromosome-specific aneuploidy. Here, by imaging specific centromeres coupled with high-throughput single-cell analysis as well as single-cell sequencing, we show that aneuploidy occurs non-randomly following common treatments to elevate chromosome mis-segregation. Temporary spindle disruption leads to elevated mis-segregation and aneuploidy of a subset of chromosomes, particularly affecting chromosomes 1 and 2. Unexpectedly, we find that a period of mitotic delay weakens centromeric cohesion and promotes chromosome mis-segregation and that chromosomes 1 and 2 are particularly prone to suffer cohesion fatigue. Our findings demonstrate that inherent properties of individual chromosomes can bias chromosome mis-segregation and aneuploidy rates, with implications for studies on aneuploidy in human disease. Copyright © 2018 The Author(s). Published by Elsevier Inc. All rights reserved.

  1. Efficacy of Lens Protection Systems: Dependency on Different Cranial CT Scans in The Acute Stroke Setting.

    PubMed

    Guberina, Nika; Forsting, Michael; Ringelstein, Adrian

    2017-06-15

    To evaluate the dose-reduction potential with different lens protectors for patients undergoing cranial computed tomography (CT) scans. Eye lens dose was assessed in vitro (α-Al2O3:C thermoluminescence dosemeters) using an Alderson-Rando phantom® in cranial CT protocols at different CT scanners (SOMATOM-Definition-AS+®(CT1) and SOMATOM-Definition-Flash® (CT2)) using two different lens-protection systems (Somatex® (SOM) and Medical Imaging Systems® (MIS)). Summarised percentage of the transmitted photons: (1) CT1 (a) unenhanced CT (nCT) with gantry angulation: SOM = 103%, MIS = 111%; (2) CT2 (a) nCT without gantry angulation: SOM = 81%, MIS = 91%; (b) CT angiography (CTA) with automatic dose-modulation technique: SOM = 39%, MIS = 74%; (c) CTA without dose-modulation technique: SOM = 22%, MIS = 48%; (d) CT perfusion: SOM = 44%, MIS = 69%. SOM showed a higher dose-reduction potential than MIS maintaining equal image quality. Lens-protection systems are most effective in CTA protocols without dose-reduction techniques. Lens-protection systems lower the average eye lens dose during CT scans up to 1/3 (MIS) and 2/3 (SOM), respectively, if the eye lens is exposed to the direct beam of radiation. Considering both the CT protocol and the material of lens protectors, they seem to be mandatory for reducing the radiation exposure of the eye lens. © The Author 2016. Published by Oxford University Press. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

  2. [Quality of data on early neonatal deaths].

    PubMed

    Pedrosa, Linda Délia Carvalho de Oliveira; Sarinho, Silvia Wanick; Ximenes, Ricardo Arraes de Alencar; Ordonha, Manoelina R

    2007-01-01

    To investigate the quality of official neonatal death data in Maceió, Alagoas. A descriptive study was conducted on early neonatal deaths in hospitals between January 1, 2001, and December 31, 2002, to compare data entry in the Death Certificate (DC) and Mortality Information System (MIS) with a standardized form filled out with data of medical files from the mothers and newborn. The frequency with which the following variables failed to be recorded in the DC and SIM was studied: type of death, address, age of mother, gender, birth weight, and delivery type, age at death and gestational age. MIS reliability was verified using simple concordance, sensitivity and Kappa indicator. MIS recorded 451 deaths, of which 50 were excluded. Mother's age was omitted from MIS in 44.1% of cases. 85.7% to 100% of the variables not filled in for the DC were recovered from the medical files. There was good concordance between DC and medical files for type of delivery, weight and age. Birth weight and age of mother presented the least concordance between medical files and MIS. MIS presented 69.2% sensitivity for weight and 36.3% for age of mother, thus demonstrating little capability to correctly supply information to generate perinatal health indicators. Because of incomplete filling out, quality of the DC becomes precarious and makes the MIS inadequate, even though it covers 100% of neonatal deaths in Maceió. Inefficiency of the system is increased by failure of MIS technicians to correct errors found and input all the information available.

  3. Design and Configuration of a Medical Imaging Systems Computer Laboratory Syllabus

    ERIC Educational Resources Information Center

    Selver, M. Alper

    2016-01-01

    Medical imaging systems (MIS) constitute an important emergent subdiscipline of engineering studies. In the context of electrical and electronics engineering (EEE) education, MIS courses cover physics, instrumentation, data acquisition, image formation, modeling, and quality assessment of various modalities. Many well-structured MIS courses are…

  4. Space Station Furnace Facility Management Information System (SSFF-MIS) Development

    NASA Technical Reports Server (NTRS)

    Mead, Robert M.

    1996-01-01

    Thios report summarizes the chronology, results, and lessons learned from the development of the SSFF-MIS. This system has been nearly two years in development and has yielded some valuable insights into specialized MIS development. Attachment A contains additions, corrections, and deletions by the COTR.

  5. Integrating Intellectual Property Concepts into MIS Education: An Empirical Assessment

    ERIC Educational Resources Information Center

    Mykytyn, Peter P., Jr.; Mykytyn, Kathleen; Harrison, David A.

    2005-01-01

    The evolving legal environment surrounding intellectual property (IP) and its impact on information systems, especially involving electronic commerce, and the type of education and training provided by management information systems (MIS) faculty to MIS students is a relationship that has not been investigated. Although organizations are…

  6. Mis-Education: A Recurring Theme? Transforming Black Religious and Theological Education

    ERIC Educational Resources Information Center

    Wright, Almeda M.

    2017-01-01

    Educating ministers and religious educators with the skills to connect with a variety of congregations and communities is a difficult task. Looking specifically at theological and religious education with African Americans, there are historical criticisms of "mis-education." "Mis-education" defined by Carter G. Woodson…

  7. Mental Space Theory and Misunderstanding

    ERIC Educational Resources Information Center

    Liu, Hui; Gao, Yueqin

    2010-01-01

    This essay attempts to conduct an explanatory research on MIS within the framework of mental space theory to demonstrate the cognitive operating process of MIS in people's social interaction and explore the deep causes lying behind the phenomenon. By text analysis, the author elaborates on the generating process of MIS, thus tracing cognitive…

  8. Investigation of MIS-sensor sensitivity to vapor of unsymmetrical dimethylgydrazine in air

    NASA Astrophysics Data System (ADS)

    Filipchuk, D. V.; Litvinov, A. V.; Etrekova, M. O.; Nozdrya, D. A.

    2018-01-01

    The sensitivity of MIS-sensor to the products of thermal decomposition of unsymmetrical dimethylhydrazine was investigated. It is shown that MIS sensor is able to detect the concentrations of the test substance by the means of the certain products of its thermal decomposition (ammonia and nitric dioxide).

  9. Perceived Requirements of MIS Curriculum Implementation in Bilingual Developing Countries

    ERIC Educational Resources Information Center

    Kabeil, Magdy M.

    2005-01-01

    This paper addresses additional requirements associated with implementing a standard curriculum of Management Information Systems (MIS) in bilingual developing countries where both students and workplace users speak English as a second language. In such countries, MIS graduates are required to develop bilingual computer applications and to…

  10. A Mis-recognized Medical Vocabulary Correction System for Speech-based Electronic Medical Record

    PubMed Central

    Seo, Hwa Jeong; Kim, Ju Han; Sakabe, Nagamasa

    2002-01-01

    Speech recognition as an input tool for electronic medical record (EMR) enables efficient data entry at the point of care. However, the recognition accuracy for medical vocabulary is much poorer than that for doctor-patient dialogue. We developed a mis-recognized medical vocabulary correction system based on syllable-by-syllable comparison of speech text against medical vocabulary database. Using specialty medical vocabulary, the algorithm detects and corrects mis-recognized medical vocabularies in narrative text. Our preliminary evaluation showed 94% of accuracy in mis-recognized medical vocabulary correction.

  11. Implementing AORN recommended practices for minimally invasive surgery: part I.

    PubMed

    Morton, Paula J

    2012-09-01

    This article focuses on the patient safety aspects of the revised AORN "Recommended practices for minimally invasive surgery" (MIS). Key considerations include ensuring proper fluid management practices, assessing patients for risk factors related to MIS, implementing precautions for electrosurgery, planning for risks related to MIS, and assessing patients postoperatively for potential complications related to MIS. Collaboration and collegiality among members of the surgical team are essential for ensuring all pertinent aspects of care are recognized and considered. Copyright © 2012 AORN, Inc. Published by Elsevier Inc. All rights reserved.

  12. Metal-Insulator-Semiconductor Diode Consisting of Two-Dimensional Nanomaterials.

    PubMed

    Jeong, Hyun; Oh, Hye Min; Bang, Seungho; Jeong, Hyeon Jun; An, Sung-Jin; Han, Gang Hee; Kim, Hyun; Yun, Seok Joon; Kim, Ki Kang; Park, Jin Cheol; Lee, Young Hee; Lerondel, Gilles; Jeong, Mun Seok

    2016-03-09

    We present a novel metal-insulator-semiconductor (MIS) diode consisting of graphene, hexagonal BN, and monolayer MoS2 for application in ultrathin nanoelectronics. The MIS heterojunction structure was fabricated by vertically stacking layered materials using a simple wet chemical transfer method. The stacking of each layer was confirmed by confocal scanning Raman spectroscopy and device performance was evaluated using current versus voltage (I-V) and photocurrent measurements. We clearly observed better current rectification and much higher current flow in the MIS diode than in the p-n junction and the metal-semiconductor diodes made of layered materials. The I-V characteristic curve of the MIS diode indicates that current flows mainly across interfaces as a result of carrier tunneling. Moreover, we observed considerably high photocurrent from the MIS diode under visible light illumination.

  13. The effect of sociodemographic (mis)match between interviewers and respondents on unit and item nonresponse in Belgium.

    PubMed

    Vercruyssen, Anina; Wuyts, Celine; Loosveldt, Geert

    2017-09-01

    Interviewer characteristics affect nonresponse and measurement errors in face-to-face surveys. Some studies have shown that mismatched sociodemographic characteristics - for example gender - affect people's behavior when interacting with an interviewer at the door and during the survey interview, resulting in more nonresponse. We investigate the effect of sociodemographic (mis)matching on nonresponse in two successive rounds of the European Social Survey in Belgium. As such, we replicate the analyses of the effect of (mis)matching gender and age on unit nonresponse on the one hand, and of gender, age and education level (mis)matching on item nonresponse on the other hand. Recurring effects of sociodemographic (mis)match are found for both unit and item nonresponse. Copyright © 2017 Elsevier Inc. All rights reserved.

  14. Mis-Spliced Lr34 Transcript Events in Winter Wheat.

    PubMed

    Fang, Tilin; Carver, Brett F; Hunger, Robert M; Yan, Liuling

    2017-01-01

    Lr34 in wheat is a non-race-specific gene that confers resistance against multiple fungal pathogens. The resistant allele Lr34 and the susceptible allele Lr34s can be distinguished by three polymorphisms that cause alternation of deduced amino acid sequences of Lr34 at the protein level. In seedlings of a cultivar carrying the resistant Lr34r allele, only a portion (35%) of its transcripts was correctly spliced and the majority (65%) of its transcripts were incorrectly spliced due to multiple mis-splicing events. Lr34 mis-splicing events were also observed at adult plant age when this gene exerts its function. All of the mis-spliced Lr34r cDNA transcripts observed in this study resulted in a premature stop codon due to a shift of the open reading frame; hence, the mis-spliced Lr34r cDNAs were deduced to encode incomplete proteins. Even if a cultivar has a functional Lr34 gene, its transcripts might not completely splice in a correct pattern. These findings suggested that the partial resistance conferred by a quantitative gene might be due to mis-splicing events in its transcripts; hence, the resistance of the gene could be increased by eliminating or mutating regulators that cause mis-splicing events in wheat.

  15. Middle to Late Pleistocene environmental and climatic reconstruction of the human occurrence at Grotta Maggiore di San Bernardino (Vicenza, Italy) through the small-mammal assemblage

    NASA Astrophysics Data System (ADS)

    López-García, Juan Manuel; Luzi, Elisa; Peresani, Marco

    2017-07-01

    Grotta Maggiore di San Bernardino, located at an altitude of 135 m a.s.l. in the Berici Hills in northeastern Italy, is an archaeological site with a discontinuous sedimentary sequence dating from Marine Isotope Stage 7 (MIS 7) to MIS 3. In this paper we present for the first time a palaeoenvironmental and palaeoclimatic reconstruction of the sequence based on small-mammal (insectivore, bat and rodent) assemblages. Coupled with biochronological data and absolute dating together with previous studies on large mammals, birds and other studies on small mammals and pollen from comparable time-spans in Italy, the results enable us clearly to identify distinct climatic periods: the end of MIS 7 (7c to 7a) in units VIII-VII, MIS 5d in unit V, and probably MIS 5b in unit IV and an indeterminate MIS 3 interstadial in units III-II. Finally, the study shows that the early Middle Palaeolithic human occupation in Italy occurs during mild and temperate sub-stages of MIS 7 and that human groups with the same techno-cultural background (Mousterian) were well adapted to the changing environmental and climatic conditions of the Middle to Late Pleistocene in this part of southern Europe.

  16. Are minimally invasive procedures harder to acquire than conventional surgical procedures?

    PubMed

    Hiemstra, Ellen; Kolkman, Wendela; le Cessie, Saskia; Jansen, Frank Willem

    2011-01-01

    It is frequently suggested that minimally invasive surgery (MIS) is harder to acquire than conventional surgery. To test this hypothesis, residents' learning curves of both surgical skills are compared. Residents had to be assessed using a general global rating scale of the OSATS (Objective Structured Assessment of Technical Skills) for every procedure they performed as primary surgeon during a 3-month clinical rotation in gynecological surgery. Nine postgraduate-year-4 residents collected a total of 319 OSATS during the 2 years and 3 months investigation period. These assessments concerned 129 MIS (laparoscopic and hysteroscopic) and 190 conventional (open abdominal and vaginal) procedures. Learning curves (in this study defined as OSATS score plotted against procedure-specific caseload) for MIS and conventional surgery were compared using a linear mixed model. The MIS curve revealed to be steeper than the conventional curve (1.77 vs. 0.75 OSATS points per assessed procedure; 95% CI 1.19-2.35 vs. 0.15-1.35, p < 0.01). Basic MIS procedures do not seem harder to acquire during residency than conventional surgical procedures. This may have resulted from the incorporation of structured MIS training programs in residency. Hopefully, this will lead to a more successful implementation of the advanced MIS procedures. Copyright © 2010 S. Karger AG, Basel.

  17. Acute hospital costs after minimally invasive versus open lumbar interbody fusion: data from a US national database with 6106 patients.

    PubMed

    Wang, Michael Y; Lerner, Jason; Lesko, James; McGirt, Matthew J

    2012-08-01

    Retrospective multi-institutional database review. To determine if minimally invasive interbody fusion is associated with cost savings when compared with open surgery. Minimally invasive spine (MIS) surgeries are increasingly recognized as equivalent to open procedures. Although these techniques have been advocated for reducing pain, disability, and length of hospitalization, to date there has been little data demonstrating these benefits. This study analyzed inpatient hospital records from the Premier Perspective database (2002 to 2009), including patients who underwent a posterior lumbar fusion with interbody cage placement by ICD-9 code, and had implant charge codes that allowed determination if MIS pedicle screws were utilized. Exclusion criteria included a refusion surgery, deformity, >2 levels, and anterior fusion. Total costs were adjusted for covariates (age, sex, race, hospital geography and setting, payor, and comorbidities) using an analysis of covariance model. A total of 6106 patients were identified (1667 MIS and 4439 open). Length of stay (LOS) for 1-level MIS surgery averaged of 3.35 days versus 3.6 days for open surgery (P≤0.006). For 2-level MIS surgery LOS averaged of 3.4 days versus 4.03 days for open surgery (P≤0.001). Total inflation-adjusted acute hospitalization cost averaged $29,187 for 1-level MIS procedures versus $29,947 for open surgery, a nonsignificant difference (P=0.55). Total inflation-adjusted acute hospitalization cost averaged $2106 lower for 2-level MIS surgery (total costs of $33,879 for MIS vs. $35,984 for open surgery, P=0.0023). Cost savings were attributable primarily to lower room and board ($857), operating room ($359), pharmacy ($304), and laboratory ($166) costs in the MIS group. High variances in the 2-level open surgery with prolonged hospital stay also accounted for overall cost differences. This data from a large nationwide sample of hospitalizations demonstrates that MIS lumbar interbody fusion results in a statistically significant reduction in hospital LOS and a reduction in total hospital costs with 2-level surgery after adjusting for significant covariates. The majority of cost savings from MIS surgery were due to more rapid mobilization and discharge, as well as a reduction in outliers with extended hospitalizations.

  18. Refining the timing of the MIS 5e signal, West Caicos, Bristish West Indies:implications for paleoclimatic interpretation of the stratigraphic record

    NASA Astrophysics Data System (ADS)

    Kerans, C.; Zahm, C.; Bachtel, S.; Hearty, P.; Cheng, H.

    2017-12-01

    The progressive refinement of the Last Interglacial (LIG) tropical carbonate record has focused attention on the dramatically abrupt and episodic nature of this critical approximate 12 ka time window. From initial carbonate platform flooding at 133 ka to rapid sea level fall and exposure at 118 ka, the majority of present-day Bahamian and Caribbean strata were produced in a remarkably similar pattern extending from Bermuda and the Bahamas through the Cayman Islands, Yucatan, and south to the Dominican Republic. The position of coral reefs and oolitic sands of the LIG to a first order fit the global insolation-driven climate warming signal. Less well accepted/resolved is the existence of two distinct SL peaks with an intervening sea level fall implying a non-orbitally forced climate shift during this broader highstand. West Caicos, a 10 x 5 km leeward island on the Caicos Platform is an excellent example of LIG carbonate stratigraphic complexity. We collected sub-meter-resolution whole-island airborn LIDAR and decimeter-resolution UAV-constructed DEM's of the western and southern coastal outcrops to serve as a base for decimeter-scale mapping of the MIS 11, 7?, 5e, and Holocene units of the island, with particular focus on the continuous 8.4 km west coast outcrop of the MIS 5e. Seventy-five AAR relative age assignments from ooid separates, pinned by 16 U/Th dates from corals coming from MIS stage 11, lower MIS 5e, and upper MIS 5e reefs helped establish the age model for the Pleistocene-Holocene stratigraphy. The lower MIS 5e reef system averages 128 ka with an onset age of 133 ka. Upper MIS 5e corals ranges from 123 ka to 116 ka, bracketing the intra-MIS 5e sea-level fall between to approximately 125 ka. The intra-MIS 5e fall is a distinct erosional unconformity across 5 km of continuous outcrop, truncating the upper 2.5 m of lower 5e reef. The complexity of MIS 5e record on West Caicos and in the Northern Atlantic and Caribbean platforms regionally provides important insights for those using the Pleistocene as a model for older stratigraphic successions and their linked paleoclimatic records.

  19. A Detailed Record of Changing Surface Water Conditions From Sediments Deposited During Marine Isotope Stage 11, ODP Site 980, Northeast Atlantic Ocean

    NASA Astrophysics Data System (ADS)

    Arvin, T. A.; Cullen, J. L.; Oppo, D. W.; McManus, J. F.

    2004-05-01

    Many recent paleoceanographic studies have focused on using high sedimentation rate deep-sea sediment sections that have produced records of abrupt climate variability operating at sub-orbital time scales. This is particularly true in the North Atlantic where proxies of changing surface water conditions from high quality sediment records have repeatedly demonstrated that millennial-scale climate change has been the rule rather than the exception over the past 500 kyr, during both glacial and interglacial intervals. Abrupt climate change during warm interglacials is an area of special interest as it may relate more directly to an understanding of recent and future climate change. With this in mind we have focused our efforts on documenting millennial-scale climate change from sediments deposited at ODP Site 980, northeast Atlantic Ocean during Marine Isotope Stage (MIS) 11. We have used unsplit, whole sample >150 micron size fractions from over 200 sediment samples to record changes in the number lithic grains per gram sediment to measure changes in the input of Ice-Rafted Debris (IRD). We then compare our new IRD record to previously generated records of changing surface water conditions during MIS11: variations in oxygen isotopic composition of the surface dwelling planktic foraminifer species N. pachyderma, right coiling and changes in the relative abundance of the polar species N. pachyderma, left coiling. Our MIS11 results are then compared to compatible records from MIS5e and the Holocene. Our detailed IRD record from around 418 kya to 382 kya reveals a remarkable lack of even trace amounts IRD input into sediments at ODP Site 980. IRD concentration abruptly drops and remains 0 to trace amounts per gram as soon as benthic delta O-18 values fall to and remain at < 3.5 per mil at the onset of MIS11. Only three very small amplitude IRD events are observed over the entire 35 kyr interval. The earliest 8 kyr of MIS11 is completely devoid of any IRD, despite the fact that the relative abundance of the polar species N. pachyderma, left coiling, after dropping from near 90% to below 10% at 418 kya, rises to as high as 30% during this early MIS11 time interval. This seems to indicate the influx of non-ice bearing colder polar waters to the region above Site 980 that don't seem to be influencing he N. pachyderma, right coiling isotope record in a simple way. The MIS11 IRD record significantly differs from our records from MIS5e and the Holocene, particularly when we focus on the earliest 12 kyr of MIS11. Both the approximately 10 kyr long MIS5e interval and the last 11 kyr of the Holocene exhibit a series of between 6 and 9 discrete small amplitude increases in IRD against a background of little or no IRD. At the same time relative abundances of N. pachyderma, left coiling are considerably less during both MIS5e and the Holocene when compared to the first 10 kyr of MIS11. The evidence presented here suggests that MIS11 surface water conditions above Site 980 were somewhat different from conditions recorded in sediments from two other warm interglacial intervals, MIS5e and the Holocene and that its use as an ancient analog to modern and future climate may be less straightforward than previously thought.

  20. Comprehensive malnutrition inflammation score as a marker of nutritional status in Chinese peritoneal dialysis patients.

    PubMed

    Chan, Jessie Ying Wing; Che, Kit I; Lam, Karry Mau Chu; Chow, Kai-Ming; Chung, Kwok-Yi; Li, Philip Kam-Tao; Szeto, Cheuk-Chun

    2007-04-01

    Malnutrition is common among peritoneal dialysis (PD) patients. However, the ideal marker of nutritional status in PD patients remained controversial. We studied 165 unselected adult PD patients. We compared the comprehensive Malnutrition-Inflammation Score (MIS) and the 7-point Subjective Global Assessment (SGA) score. The mean age was 59.2 +/- 11.5 years. Seventy patients were male. MIS significantly correlated with the SGA score (r =-0.667, P < 0.001). Of the 165 patients, 132 (80.0%) had similar classification of nutritional status by SGA and MIS (Group I); 17 (10.3%) were classified as normal by SGA but moderately malnourished by MIS (Group II), while 16 (9.7%) were classified as normal by MIS but moderately malnourished by SGA (Group III). Group II had been dialysed longer than Group I (71.7 +/- 50.3 vs 40.7 +/- 37.5 months, P = 0.011). As compared with Group I, Group III was more likely to require helper for PD exchange (37.5%vs 9.7%, P = 0.004), marginally more likely to be diabetic (62.5%vs 35.6%, P = 0.085) and had a slightly higher Charlson's comorbidity score (6.13 +/- 1.78 vs 4.98 +/- 2.1, P = 0.085), although the latter two were not statistically significant. MIS has a reasonable correlation with the conventional SGA score in PD patients. Patients with limited self-care capability, diabetes and multiple comorbidities probably had worse score (i.e. worse nutrition) revealed by SGA than by MIS, while patients who had been dialysed longer had worse score revealed by MIS than by SGA.

  1. A Last Interglacial pollen-temperature reconstruction, central North Island, New Zealand

    NASA Astrophysics Data System (ADS)

    Newnham, Rewi; Alloway, Brent; McGlone, Matt; Juchnowicz, Hannah; Rees, Andrew; Wilmshurst, Janet

    2017-08-01

    We present new pollen-temperature reconstructions for the Last Interglacial from central North Island, New Zealand using partial least squares regression (PLS) and modern analogue technique applied with the New Zealand pre-deforestation calibration pollen dataset. The pollen-bearing organic sequence includes numerous millimetre- to decimetre- thick tephra mostly from the adjacent Tongariro Volcanic Centre and is overlain by tephric cover-beds including the c. 25.4 ka cal BP Kawakawa/Oruanui Tephra. Fine-resolution pollen and preliminary diatom analyses above and below prominent tephra layers showed that significant vegetation impact followed only the thickest ashfall event (22 cm thickness), with vegetation recovery taking several hundred years. Apart from this, changes in the longer-term pollen record are likely to be related to climate oscillations that resemble the classic five-fold subdivision of MIS 5. The warmest interval, ascribed to MIS 5e, was characterised by tall, temperate rainforest, and occurs at the base of the sequence, with mean annual temperatures reaching around 1.1 °C higher than present. Mean annual temperatures declined to ∼4 °C below present during MIS 5d and MIS 5b and were within 1-2 °C of present during MIS 5c. The PLS temperature reconstructions are corroborated by estimates derived independently from elevational changes to vegetation communities, corresponding to modern temperature controls, inferred from the Karioi pollen spectra. Temperatures reconstructed quantitatively by the modern analogue technique were up to 1.3 °C higher for MIS 5e, MIS 5d and MIS 5b, possibly reflecting weaker modern vegetation analogues for these intervals.

  2. Dialysis Malnutrition and Malnutrition Inflammation Scores: screening tools for prediction of dialysis-related protein-energy wasting in Malaysia.

    PubMed

    Harvinder, Gilcharan Singh; Swee, Winnie Chee Siew; Karupaiah, Tilakavati; Sahathevan, Sharmela; Chinna, Karuthan; Ahmad, Ghazali; Bavanandan, Sunita; Goh, Bak Leong

    2016-01-01

    Malnutrition is highly prevalent in Malaysian dialysis patients and there is a need for a valid screening tool for early identification and management. This cross-sectional study aims to examine the sensitivity of the Dialysis Malnutrition Score (DMS) and Malnutrition Inflammation Score (MIS) tools in predicting protein-energy wasting (PEW) among Malaysian dialysis patients. A total of 155 haemodialysis (HD) and 90 peritoneal dialysis (PD) patients were screened for risk of malnutrition using DMS and MIS and comparisons were made with established guidelines by International Society of Renal Nutrition and Metabolism (ISRNM) for PEW. MIS cut-off score of >=5 indicated presence of malnutrition in all patients. A total of 59% of HD and 83% of PD patients had PEW by ISRNM criteria. Based on DMS, 73% of HD and 71% of PD patients exhibited moderate malnutrition, whilst using MIS, 88% and 90%, respectively were malnourished. DMS and MIS correlated significantly in HD (r2=0.552, p<0.001) and PD (r2=0.466, p<0.001) patients. DMS and MIS had higher sensitivity values in PD (81% and 82%, respectively) compared to HD (59% and 60%, respectively) patients. The MIS cut-off scores for malnutrition classification were established (score >=5) for use amongst Malaysian dialysis patients. Both DMS and MIS are valid tools to be used for nutrition screening of dialysis patients especially those undergoing peritoneal dialysis. The DMS may be a more practical and simpler tool to be utilized in the Malaysian dialysis settings as it does not require laboratory markers.

  3. Information Will Not Make You Well. MIS Re-examined. AIR Forum Paper 1978.

    ERIC Educational Resources Information Center

    Parker, John D.; Gardner, Don E.

    Proponents of management information systems (MIS) have traditionally held that educational administrators are in need of better management information with which to make more informed planning and policy decisions. However, few successful implementations have been reported. Literature discussing the lack of success of MIS point to such factors as…

  4. 75 FR 8528 - Procedures for Transportation Workplace Drug and Alcohol Testing Programs

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-02-25

    ... updated U.S. DOT Alcohol Testing Form (ATF) and the Management Information System (MIS) Data Collection... included a revised U.S. DOT Alcohol Testing Form (ATF) and the Management Information System (MIS) Data...) and Management Information System (MIS) form Federal Register [73 FR 14300] and [73 FR 33140]. There...

  5. Management Information Systems: Applications to Educational Administration.

    ERIC Educational Resources Information Center

    Witkin, Belle Ruth

    An orientation to management information systems (MIS) is offered which presents information about MIS in the context of public education and suggests some considerations that should be taken into account in designing and operating such systems. MIS is defined as a set of operating procedures that act as a control system to automatically provide…

  6. Concepts of Management Information Systems.

    ERIC Educational Resources Information Center

    Emery, J.C.

    The paper attempts to provide a general framework for dealing with management information systems (MIS). An MIS is defined to have the following characteristics: (1) related to ongoing activities of an organization, (2) a man-machine system, (3) composed of a collection of subsystems, and (4) oriented around a large data base. An MIS places a…

  7. MIS Development in Higher Education: A Framework for Systems Planning.

    ERIC Educational Resources Information Center

    St. John, Edward P.

    An institutional management systems development study examined the Management Information Systems (MIS) needs of 23 public institutions of higher education in Missouri. The result was a model framework for other institutions to develop MIS appropriate to their needs. One of five distinct structural development phases could be related to all…

  8. The Role of Cognitive Abilities in Laparoscopic Simulator Training

    ERIC Educational Resources Information Center

    Groenier, M.; Schraagen, J. M. C.; Miedema, H. A. T.; Broeders, I. A. J. M.

    2014-01-01

    Learning minimally invasive surgery (MIS) differs substantially from learning open surgery and trainees differ in their ability to learn MIS. Previous studies mainly focused on the role of visuo-spatial ability (VSA) on the learning curve for MIS. In the current study, the relationship between spatial memory, perceptual speed, and general…

  9. Effects of Camera Arrangement on Perceptual-Motor Performance in Minimally Invasive Surgery

    ERIC Educational Resources Information Center

    Delucia, Patricia R.; Griswold, John A.

    2011-01-01

    Minimally invasive surgery (MIS) is performed for a growing number of treatments. Whereas open surgery requires large incisions, MIS relies on small incisions through which instruments are inserted and tissues are visualized with a camera. MIS results in benefits for patients compared with open surgery, but degrades the surgeon's perceptual-motor…

  10. Pharmacological intervention of HIV-1 maturation.

    PubMed

    Wang, Dan; Lu, Wuxun; Li, Feng

    2015-11-01

    Despite significant advances in antiretroviral therapy, increasing drug resistance and toxicities observed among many of the current approved human immunodeficiency virus (HIV) drugs indicate a need for discovery and development of potent and safe antivirals with a novel mechanism of action. Maturation inhibitors (MIs) represent one such new class of HIV therapies. MIs inhibit a late step in the HIV-1 Gag processing cascade, causing defective core condensation and the release of non-infectious virus particles from infected cells, thus blocking the spread of the infection to new cells. Clinical proof-of-concept for the MIs was established with betulinic acid derived bevirimat, the prototype HIV-1 MI. Despite the discontinuation of its further clinical development in 2010 due to a lack of uniform patient response caused by naturally occurring drug resistance Gag polymorphisms, several second-generation MIs with improved activity against viruses exhibiting Gag polymorphism mediated resistance have been recently discovered and are under clinical evaluation in HIV/AID patients. In this review, current understanding of HIV-1 MIs is described and recent progress made toward elucidating the mechanism of action, target identification and development of second-generation MIs is reviewed.

  11. BatMis: a fast algorithm for k-mismatch mapping.

    PubMed

    Tennakoon, Chandana; Purbojati, Rikky W; Sung, Wing-Kin

    2012-08-15

    Second-generation sequencing (SGS) generates millions of reads that need to be aligned to a reference genome allowing errors. Although current aligners can efficiently map reads allowing a small number of mismatches, they are not well suited for handling a large number of mismatches. The efficiency of aligners can be improved using various heuristics, but the sensitivity and accuracy of the alignments are sacrificed. In this article, we introduce Basic Alignment tool for Mismatches (BatMis)--an efficient method to align short reads to a reference allowing k mismatches. BatMis is a Burrows-Wheeler transformation based aligner that uses a seed and extend approach, and it is an exact method. Benchmark tests show that BatMis performs better than competing aligners in solving the k-mismatch problem. Furthermore, it can compete favorably even when compared with the heuristic modes of the other aligners. BatMis is a useful alternative for applications where fast k-mismatch mappings, unique mappings or multiple mappings of SGS data are required. BatMis is written in C/C++ and is freely available from http://code.google.com/p/batmis/

  12. Glaciomarine sedimentation and bottom current activity on the north-western and northern continental margins of Svalbard during the late Quaternary

    NASA Astrophysics Data System (ADS)

    Chauhan, Teena; Noormets, Riko; Rasmussen, Tine L.

    2016-04-01

    Palaeo-bottom current strength of the West Spitsbergen Current (WSC) and the influence of the Svalbard-Barents Sea Ice Sheet (SBIS) on the depositional environment along the northern Svalbard margins are poorly known. Two gravity cores from the southern Yermak Plateau and the upper slope north of Nordaustlandet, covering marine isotope stage (MIS) 1 to MIS 5, are investigated. Five lithofacies, based on grain size distribution, silt/clay ratio, content and mean of sortable silt (SS), are distinguished to characterise the contourite-dominated sedimentary environments. In addition, depositional environments are described using total organic carbon (TOC), total sulphur (TS) and calcium carbonate (CaCO3) contents of sediments. Facies A, containing coarse SS, suggests strong bottom current activity and good bottom water ventilation conditions as inferred from low TOC content. This facies was deposited during the glacial periods MIS 4, MIS 2 and during the late Holocene. Facies B is dominated by fine SS indicating weak bottom current and poor ventilation (cf. high TOC content of 1.2-1.6%), and correlates with the MIS 4/3 and MIS 2/1 transition periods. With an equal amount of clay and sand, fine SS and high content of TOC, facies C indicates reduced bottom current strength for intervals with sediment supply from proximal sources such as icebergs, sea ice or meltwater discharge. This facies was deposited during the last glacial maximum. Facies D represents mass-flow deposits on the northern Svalbard margin attributed to the SBIS advance at or near the shelf edge. Facies E sediments indicating moderate bottom current strength were deposited during MIS 5 and MIS 3, and during parts of MIS 2. This first late Quaternary proxy record of the WSC flow and sedimentation history from the northern Svalbard margin suggests that the oceanographic conditions and ice sheet processes have exerted first-order control on sediment properties.

  13. Relative sea-level changes and glacio-isostatic adjustment on the Magdalen Islands archipelago (Atlantic Canada) from MIS 5 to the late Holocene

    NASA Astrophysics Data System (ADS)

    Rémillard, Audrey M.; St-Onge, Guillaume; Bernatchez, Pascal; Hétu, Bernard; Buylaert, Jan-Pieter; Murray, Andrew S.; Lajeunesse, Patrick

    2017-09-01

    The Magdalen Islands (Québec, Canada) in the centre of the Gulf of St. Lawrence are located in a strategic position for providing an overview of the relative sea-level (RSL) history of the Maritime Provinces of eastern Canada. Although data are available for the coastal terrestrial areas of the Maritimes, data from the Gulf are very scarce and both the RSL and glacio-isostatic adjustment (GIA) models extrapolate for this central region. This study provides new stratigraphic and chronological data from four outcrops and two coring sites on the Magdalen Islands. In addition to the five samples used mainly for age control purposes, nine new luminescence ages are presented. With these new data added to the available literature, a new RSL curve is reconstructed for the LGM to the late Holocene period and a partial curve is proposed for the interval between the late MIS 4 to the MIS 3. Data also indicate a few insights for the MIS 5 period. Results reveal that for the LGM to the late Holocene, the curve corresponds to the J-shaped curve scenario recognized in the literature. The RSL changes during this period are the result of glacio-isostatic rebound, migration and collapse of the peripheral forebulge, and eustatic sea-level changes. For the LGM to the early Holocene, glacio-isostatic depression curves displaying a few local differences are also proposed. For the late Holocene, the data constrain the curve between two types of indicators, i.e. marine and terrestrial, and indicate that the RSL has risen at least 3 m during the last two millennia. Sediments dated to the MIS 5 and the interval between the late MIS 4 and the MIS 3 illustrate that the GIA following the LGM also occurred for the MIS 5 interglacial and the MIS 3 interstadial. Finally, recent GIA models are discussed in light of the results of this paper.

  14. Comparative Effectiveness of Minimally Invasive Surgery and Conventional Approaches to Major or Challenging Hepatectomy

    PubMed Central

    Thornblade, Lucas W; Shi, Xu; Ruiz, Alex; Flum, David R; Park, James O

    2017-01-01

    Background The benefits of minimally invasive surgery (MIS) for low-risk or minor liver resection are well established. There is growing interest in MIS for major hepatectomy (MH) and other challenging resections, but there remain unanswered questions of safety that prevent broad adoption of this technique. Study Design Retrospective cohort study of patients undergoing hepatectomy at 65 hospitals participating in the NSQIP Hepatopancreatobiliary Collaborative in 2014. We assessed serious morbidity or mortality (SMM, including organ-space infection and organ failure). Secondary outcomes included transfusion, bile leak, liver failure, reoperation or intervention, and 30-day readmission. We also measured factors considered to make resection more challenging (large tumors, cirrhosis, ≥3 concurrent resections, prior neoadjuvant chemotherapy, or morbid obesity). Results 2819 patients underwent hepatectomy (age 58±14 years, 53% female; 25% MIS). After adjusting for clinical and operative factors, the odds of SMM (OR=0.57, 95%CI: 0.34–0.96, p=0.03) and reoperation or intervention (OR=0.52 (0.29–0.93), p=0.03) were significantly lower for patients undergoing MIS compared with open. In the MH group (n=1,015; 13% MIS), there was no difference in the odds of SMM after MIS (OR=0.37, (0.13–1.11), p=0.08) however MIS MH met criteria for non-inferiority. There were no differences in liver-specific complications or readmission between the groups. Odds of SMM were significantly lower following MIS among patients who had received neoadjuvant chemotherapy (OR 0.33 (0.15–0.70), p=0.004). Conclusion In this large study of minimally invasive major hepatectomy, we demonstrate safety outcomes that are equivalent or superior to conventional open surgery. While the decision to offer MIS may be influenced by factors not included in this evaluation, (e.g. surgeon experience and other patient factors), these findings support its current use in major hepatectomies. PMID:28163089

  15. The Plumbing System of a Highly Explosive Basaltic Volcano: Sunset Crater, AZ

    NASA Astrophysics Data System (ADS)

    Allison, C. M.; Roggensack, K.; Clarke, A. B.

    2015-12-01

    We seek to better understand highly explosive basaltic eruptions with specific focus on magmatic volatile solubility in alkali basalts and the magma plumbing system. Sunset Crater, an alkali basalt (~3.7 wt.% alkalis) scoria cone volcano, erupted explosively in 1085 AD. We analyzed 125 primary melt inclusions (MIs) from Sunset Crater tephra deposited by 2 subplinian phases and 1 Strombolian explosion to compare magma volatiles and storage conditions. We picked rapidly quenched free olivine crystals and selected large volume MIs (50-180 μm) located toward crystal cores. MIs are faceted and exhibit little major element composition variability with minor post entrapment crystallization (2-10%). MIs are relatively dry but CO2-rich. Water content varies from 0.4 wt.% to 1.5 wt.% while carbon dioxide abundance ranges between 1,150 ppm and 3,250 ppm. Most MIs contain >1 wt.% H2O and >2,150 ppm CO2. All observed MIs contain a vapor bubble, so we are evaluating MI vapor bubbles with Raman spectroscopy and re-homogenization experiments to determine the full volatile budget. Because knowledge of volatile solubility is critical to accurately interpret results from MI analyses, we measured H2O-CO2 solubility in the Sunset Crater bulk composition. Fluid-saturated experiments at 4 and 6 kbar indicate shallower entrapment pressures for these MIs than values calculated for this composition using existing models. Assuming fluid saturation, MIs record depths from 6 km to 14 km, including groupings suggesting two pauses for longer-term storage at ~6 km and ~10.5 km. We do not observe any significant differences in MIs from phases exhibiting different eruptive styles, suggesting that while a high CO2 content may drive rapid magma ascent and be partly responsible for highly explosive eruptions, shallower processes may govern the final eruptive character. To track shallow processes during magma ascent from depth of MI-entrapment up to the surface, we are examining MI re-entrants.

  16. An emerging c. 100 ka record of climate change from Baldwin Lake, San Bernardino Mountains, CA, U.S

    NASA Astrophysics Data System (ADS)

    Glover, K. C.; MacDonald, G. M.; Kirby, M. E.; Rhodes, E. J.

    2013-12-01

    Big Bear Valley (elevation ~2060 m) is situated in the east-west trending San Bernardino Mountains of California, close to the transition between Mediterranean and Mojave Desert ecoregions. Baldwin Lake is the older of two basins occupying the valley, with a sediment sequence that demonstrates a high rate of deposition and an apparent synchronicity with marine isotope and global paleoclimate records. Chronology has been established with both AMS radiocarbon and infra-red stimulated luminescence (IRSL) dates. This offers the potential to further investigate paleoclimate change over the past c. 100 ka for Southern California at a high temporal resolution. Baldwin Lake's basal date of 95.9 +/- 6.7 ka is derived from IRSL on feldspar grains, placing the onset of sedimentation into the modern basin during cool MIS 5(b). Phases of high productivity in the lake, including values of up to 35% total organic matter and marl facies, correlate with warm events MIS 5(a) and MIS 3. Glacial stages are largely defined by inorganic sedimentation, though depositional regime varies between high-energy MIS 5(b) and MIS 4, and a relatively quiescent MIS 2. Future work will reconstruct vegetation change prior to MIS 1, in order to elucidate millennial-scale changes in alpine groundcover and forests in Southern California during these globally pervasive Stages.

  17. Late Quaternary sea-level history and the antiquity of mammoths (Mammuthus exilis and Mammuthus columbi), Channel Islands NationalPark, California, USA

    USGS Publications Warehouse

    Muhs, Daniel R.; Simmons, Kathleen R.; Groves, Lindsey T.; McGeehin, John P.; Schumann, R. Randall; Agenbroad, Larry D.

    2015-01-01

    Fossils of Columbian mammoths (Mammuthus columbi) and pygmy mammoths (Mammuthus exilis) have been reported from Channel Islands National Park, California. Most date to the last glacial period (Marine Isotope Stage [MIS] 2), but a tusk of M. exilis (or immature M. columbi) was found in the lowest marine terrace of Santa Rosa Island. Uranium-series dating of corals yielded ages from 83.8 ± 0.6 ka to 78.6 ± 0.5 ka, correlating the terrace with MIS 5.1, a time of relatively high sea level. Mammoths likely immigrated to the islands by swimming during the glacial periods MIS 6 (~ 150 ka) or MIS 8 (~ 250 ka), when sea level was low and the island–mainland distance was minimal, as during MIS 2. Earliest mammoth immigration to the islands likely occurred late enough in the Quaternary that uplift of the islands and the mainland decreased the swimming distance to a range that could be accomplished by mammoths. Results challenge the hypothesis that climate change, vegetation change, and decreased land area from sea-level rise were the causes of mammoth extinction at the Pleistocene/Holocene boundary on the Channel Islands. Pre-MIS 2 mammoth populations would have experienced similar or even more dramatic changes at the MIS 6/5.5 transition.

  18. Preparation a new sorbent based on polymeric ionic liquid for stir cake sorptive extraction of organic compounds and inorganic anions.

    PubMed

    Huang, Xiaojia; Wang, Yulei; Hong, Qiuyun; Liu, Yi; Yuan, Dongxing

    2013-11-01

    A new multi-interaction sorbent (MIS) based on polymeric ionic liquid was prepared and used as extractive medium of stir cake sorptive extraction (SCSE). In the presence of dimethyl sulfoxide, an ionic liquid, 1-vinylbenzyl-3-methylimidazolium chloride was used as monomer to copolymerize in situ with divinylbenzene to form the MIS. The influences of the content of monomer and the porogen solvent in the polymerization mixture on the extraction performance were investigated thoroughly. The MIS was characterized by infrared spectroscopy, elemental analysis, scanning electron microscopy and mercury intrusion porosimetry. Parabens and aromatic amines were used to investigate the extraction performance of MIS-SCSE for apolar and strongly polar analytes, respectively. The extraction parameters for parabens and aromatic amines were optimized. At the same time, simple and sensitive analytical methods for parabens and aromatic amines in real samples were developed by the combination of MIS-SCSE and HPLC/DAD. Some inorganic anions, such as F(-), Br(-), NO3(-), PO4(3-) and SO4(2-), were used to test the extraction performance of MIS-SCSE for anions. Results indicated that mechanism involved in the extraction of MIS is the multi-interaction modes including π-π, hydrophobic, hydrogen-bonding, dipole-dipole and anion-exchange interactions. Copyright © 2013 Elsevier B.V. All rights reserved.

  19. A loess-paleosol record of climate and glacial history over the past two glacial-interglacial cycles (~140 ka), southern Jackson Hole, Wyoming

    USGS Publications Warehouse

    Pierce, Kenneth L.; Muhs, Daniel R.; Fosberg, Maynard A.; Mahan, Shannon; Rosenbaum, Joseph G.; Licciardi, Joseph M.; Pavich, Milan J.

    2011-01-01

    Loess accumulated on a Bull Lake outwash terrace of Marine Oxygen Isotope Stage 6 (MIS 6) age in southern Jackson Hole, Wyoming. The 9 m section displays eight intervals of loess deposition (Loess 1 to Loess 8, oldest), each followed by soil development. Our age-depth model is constrained by thermoluminescence, meteoric Be-10 accumulation in soils, and cosmogenic Be-10 surface exposure ages. We use particle size, geochemical, mineral-magnetic, and clay mineralogical data to interpret loess sources and pedogenesis. Deposition of MIS 6 loess was followed by a tripartite soil/thin loess complex (Soils 8,7, and 6) apparently reflecting the large climatic oscillations of MIS 5. Soil 8 (MIS 5e) shows the strongest development. Loess 5 accumulated during a glacial interval (similar to 76-69 ka; MIS 4) followed by soil development under conditions wetter and probably colder than present. Deposition of thick Loess 3 (similar to 43-51 ka, MIS 3) was followed by soil development comparable with that observed in Soil 1. Loess 1 (MIS 2) accumulated during the Pinedale glaciation and was followed by development of Soil 1 under a semiarid climate. This record of alternating loess deposition and soil development is compatible with the history of Yellowstone vegetation and the glacial flour record from the Sierra Nevada. Published by Elsevier Inc. on behalf of University of Washington.

  20. STABILIZED TRANSISTOR AMPLIFIER

    DOEpatents

    Noe, J.B.

    1963-05-01

    A temperature stabilized transistor amplifier having a pair of transistors coupled in cascade relation that are capable of providing amplification through a temperature range of - 100 un. Concent 85% F to 400 un. Concent 85% F described. The stabilization of the amplifier is attained by coupling a feedback signal taken from the emitter of second transistor at a junction between two serially arranged biasing resistances in the circuit of the emitter of the second transistor to the base of the first transistor. Thus, a change in the emitter current of the second transistor is automatically corrected by the feedback adjustment of the base-emitter potential of the first transistor and by a corresponding change in the base-emitter potential of the second transistor. (AEC)

  1. Training for an MIS Implementation: What Does it Really Cost?

    PubMed Central

    Jacobs, Patt

    1984-01-01

    Implementation of MIS systems in a hospital environment are complex, problematic, long-term endeavors. St. Vincent Hospital and Medical Center (SVHMC) completed the implementation of its base system MIS five years after the original contract was signed. The cost of that implementation in terms of time and dollars for one aspect only, training is reported.

  2. Integrating IS Curriculum Knowledge through a Cluster-Computing Project--A Successful Experiment

    ERIC Educational Resources Information Center

    Kitchens, Fred L.; Sharma, Sushil K.; Harris, Thomas

    2004-01-01

    MIS curricula in business schools are challenged to provide MIS courses that give students a strong practical understanding of the basic technologies, while also providing enough hands-on experience to solve real life problems. As an experimental capstone MIS course, the authors developed a cluster-computing project to expose business students to…

  3. An Empirical Study about the Critical Factors Affecting MIS Students' Job Opportunities

    ERIC Educational Resources Information Center

    Fang, Xiang; Lee, Sooun

    2005-01-01

    For the first time in many years, Management Information Systems (MIS) students and faculty are seeking ways to improve full-time job placement for program graduates. Due to sharp IT budget cuts, the slowing economy, and outsourcing, job opportunities for MIS graduates have become scarcer than ever before. In addition to achieving good academic…

  4. Gender Differences and Intra-Gender Differences amongst Management Information Systems Students

    ERIC Educational Resources Information Center

    Beyer, Sylvia

    2008-01-01

    Few women major in Management Information Systems (MIS). The purpose of this paper is to examine the reasons for women's underrepresentation in MIS. In addition to examining gender differences, an important and novel goal of this study is to examine intra-gender differences in undergraduate students, i.e., differences among female MIS majors and…

  5. Transistor Effect in Improperly Connected Transistors.

    ERIC Educational Resources Information Center

    Luzader, Stephen; Sanchez-Velasco, Eduardo

    1996-01-01

    Discusses the differences between the standard representation and a realistic representation of a transistor. Presents an experiment that helps clarify the explanation of the transistor effect and shows why transistors should be connected properly. (JRH)

  6. Late Pleistocene Age Model for Site U1460, Perth Basin, SW Australian Shelf: Implications for Leeuwin Current History

    NASA Astrophysics Data System (ADS)

    Christensen, B. A.; Takayanagi, H.; Petrick, B.; Ishiwa, T.; Henderiks, J.; Groeneveld, J.; Mamo, B. L.; De Vleeschouwer, D.; Auer, G.; Deik, H.; Fulthorpe, C.; Gallagher, S. J.; McHugh, C.; Reuning, L.; Yokoyama, Y.

    2017-12-01

    The Leeuwin Current (LC) exerts an important control on modern Australian climate, but its onset is not well defined. The LC is the only southward flowing eastern boundary current. Driven by a pressure gradient set up in the Indonesian Throughflow, its warm waters support reefs to 29°S. It is seasonally controlled south of the Western Cape. Determination of the onset of the LC was a major objective of IODP Expedition 356. Expedition 356 drilling on the western Australian margin provides an opportunity to explore depositional patterns and timing in the region influenced by the current. Site U1460 was drilled in 214.5 m w.d. (Gallagher et al., 2017). Integrated calcareous nannofossil and planktonic foraminiferal biostratigraphy places the upper 86.5 m firmly within the late Pleistocene. However, the glacial- interglacial stratigraphy is uncertain because of the complexity of this shelfal depositional environment. Here we present a likely late Pleistocene stratigraphy based on integrated geochemical and paleontological datasets. A benthic foraminifer (Uvigerina peregrina) stable isotope record provides the foundation for the age model and the data are supported by SST estimates based on Tex86 and alkenones. Our age model places MIS 16 between 104 and 99 m-CSF-A, followed by an expanded MIS 15 section (99 - 50 m-CSF-A). We correlate the interval from 50 - 5 m-CSF-A with MIS 14 to MIS 8, with the largest magnitude glacial events (MIS 12, MIS 6) either condensed or represented as depositional hiatuses. A Recent 14C date at 0.34 mbsf constrains the interval from 2 - 0.5 m-CSF-A to MIS 4-3, which is in good agreement with the base of common Emiliania huxleyi (0.09 Ma) at 2.13 m-CSF-A. Thus MIS 5 is equivalent to the interval from 5 to 2 m-CSF-A. The expanded MIS 15 section follows a geometric change from slope to prograding shelf. It is associated with a shift to infaunal benthic foraminiferal assemblages, abundant sponge spicules, and a reduction in CaCO3%, suggesting that the high MIS 15 sedimentation rate results from increased productivity and/or upwelling. Our stable-isotope-based correlation, combined with paleotemperature reconstructions, points to a modern-like LC in operation at 0.6 Ma (MIS 16 onward), following a change in continental margin geometry. Alternative age-depth models are possible, and are also presented.

  7. Relative to open surgery, minimally-invasive renal and ureteral pediatric surgery offers no improvement in 30-day complications, yet requires longer operative time: Data from the National Surgical Quality Improvement Program Pediatrics.

    PubMed

    Colaco, Marc; Hester, Austin; Visser, William; Rasper, Alison; Terlecki, Ryan

    2018-05-01

    Performance of minimally-invasive surgery (MIS) is increasing relative to open surgery. We sought to compare the contemporary rates of short-term complications of open versus laparoscopic renal and ureteral surgery in pediatric patients. A retrospective cross-sectional analysis of the National Surgical Quality Improvement Program Pediatrics database was performed of all cases in 2014 identified using CPT procedure codes for nephrectomy, partial nephrectomy (PN), ureteroneocystostomy (UNC), and pyeloplasty, and reviewed for postoperative complications. Univariate analysis was performed to determine 30-day complications, with comparison between open and MIS approaches. Receiver operator curve (ROC) analysis was performed to determine differences in body surface area (BSA) and age for open versus MIS. Review identified 207 nephrectomies, 72 PN, 920 UNC, and 625 pyeloplasties. MIS was associated with older age and larger BSA except for cases of UNC. Apart from PN, operative durations were longer with MIS. However, only PN was associated with significantly longer length of hospital stay (LOS). There was no difference in incidence of all other 30-day complications. When evaluating BSA via ROC, the area under the curve (AUC) was found to be 0.730 and was significant. Children with a BSA greater than 0.408 m 2 were more likely to have MIS (sensitivity, 66.9%; specificity, 69.3%). Regarding age, the AUC was 0.732. Children older than 637.5 days were more likely to have MIS (sensitivity, 72.8%; specificity, 63.3%). Pediatric MIS is associated with longer operative time for nephrectomy, but shorter LOS following PN. Surgical approach was not associated with difference in short-term complications.

  8. Similar millennial climate variability on the Iberian margin during two early Pleistocene glacials and MIS 3

    NASA Astrophysics Data System (ADS)

    Birner, B.; Hodell, D. A.; Tzedakis, P. C.; Skinner, L. C.

    2016-01-01

    Although millennial-scale climate variability (<10 ka) has been well studied during the last glacial cycles, little is known about this important aspect of climate in the early Pleistocene, prior to the Middle Pleistocene Transition. Here we present an early Pleistocene climate record at centennial resolution for two representative glacials (marine isotope stages (MIS) 37-41 from approximately 1235 to 1320 ka) during the "41 ka world" at Integrated Ocean Drilling Program Site U1385 (the "Shackleton Site") on the southwest Iberian margin. Millennial-scale climate variability was suppressed during interglacial periods (MIS 37, MIS 39, and MIS 41) and activated during glacial inceptions when benthic δ18O exceeded 3.2‰. Millennial variability during glacials MIS 38 and MIS 40 closely resembled Dansgaard-Oeschger events from the last glacial (MIS 3) in amplitude, shape, and pacing. The phasing of oxygen and carbon isotope variability is consistent with an active oceanic thermal bipolar see-saw between the Northern and Southern Hemispheres during most of the prominent stadials. Surface cooling was associated with systematic decreases in benthic carbon isotopes, indicating concomitant changes in the meridional overturning circulation. A comparison to other North Atlantic records of ice rafting during the early Pleistocene suggests that freshwater forcing, as proposed for the late Pleistocene, was involved in triggering or amplifying perturbations of the North Atlantic circulation that elicited a bipolar see-saw response. Our findings support similarities in the operation of the climate system occurring on millennial time scales before and after the Middle Pleistocene Transition despite the increases in global ice volume and duration of the glacial cycles.

  9. Accuracy of percutaneous pedicle screws for thoracic and lumbar spine fractures compared with open technique.

    PubMed

    Paredes, Igor; Panero, Irene; Cepeda, Santiago; Castaño-Leon, Ana M; Jimenez-Roldan, Luis; Perez-Nuñez, Ángel; Alén, Jose A; Lagares, Alfonso

    2018-06-14

    This study aimed to compare the accuracy of screw placement between open pedicle screw fixation and percutaneous pedicle screw fixation (MIS) for the treatment of thoracolumbar spine fractures (TSF). Forty-nine patients with acute TSF who were treated with transpedicular screw fixation from January 2013 to December 2016 were retrospectively reviewed. The patients were divided into Open and MIS groups. Laminectomy was performed in either group if needed. The accuracy of the screw placement, the evolution of the Cobb sagital angle postoperatively and at 12-month follow up and the neurological status were recorded. AO type of fracture and TLICS score were also recorded. Mean age was 42 years old. Mean TLICS score was 6,29 and 5,96 for open and MIS groups respectively. Twenty five MIS and 24 open surgeries were performed, and 350 (175 in each group) screws were inserted (7,14 per patient). Twenty-four and 13 screws were considered ̈out ̈ in the open and MIS groups respectively (Odds ratio 1,98. 0,97-4,03 p=0,056). The Cobb sagittal angle went from 13,3o to 4,5o and from 14,9o to 8,2o in the Open and MIS groups respectively (both p<0,0001). Loss of correction at 12-month follow up was 3,2o and 4,2o for the open and MIS groups respectively. No neurological worsening was observed. For the treatment of acute thoracolumbar fractures, the MIS technique seems to achieve similar results to the open technique in relation to neurological improvement and deformity correction, while placing the screws more accurately.

  10. Insights into North Atlantic deep water formation during the peak interglacial interval of Marine Isotope Stage 9 (MIS 9)

    NASA Astrophysics Data System (ADS)

    Mokeddem, Zohra; McManus, Jerry F.

    2017-11-01

    Foraminifera abundance and stable isotope records from ODP Site 984 (61.25°N, 24.04°W, 1648 m) in the North Atlantic are used to reconstruct surface circulation variations and the relative strength of the North Atlantic Deep Water (NADW) formation over the period spanning the peak warmth of Marine Interglacial Stage (MIS) 9e ( 324-336 ka). This interval includes the preceding deglaciation, Termination 4 (T4), and the subsequent glacial inception of MIS 9d. The records indicate a greatly reduced contribution of NADW during T4, as observed in more recent deglaciations. In contrast with the most recent deglaciation, the lack of a significant NADW signal extended from T4 well into the peak interglacial MIS 9e and persisted nearly until the transition to the subsequent glacial stage MIS 9d. Although NADW formation resumed during MIS 9e, only depths greater than 2000 m appear to have been ventilated. The poorly ventilated intermediate depth of Site 984 (<2000 m) may have resulted on one hand from a general reduction of deep water ventilation by NADW during the study interval or, on the other hand, from different pathways of the spread of newly formed NADW that bypassed the study location. The intermediate depths may have also been invaded by southern-sourced waters as the formation of intermediate depth NADW weakened. The absence of any significant NADW signal at the water depth of Site 984 during the climatic optimum contrasts sharply with subsequent interglacial peaks (MIS 5e and the Holocene). Despite the perturbed intermediate depth circulation, oceanic heat transport northeastward was not interrupted and may have contributed to the relatively mild interglacial conditions of MIS 9e.

  11. Si and GaAs photocapacitive MIS infrared detectors

    NASA Technical Reports Server (NTRS)

    Sher, A.; Tsuo, Y. H.; Moriarty, J. A.; Miller, W. E.; Crouch, R. K.

    1980-01-01

    Improvement of the previously reported photocapacitive MIS infrared detectors has led to the development of exceptional room-temperature devices. Unoptimized peak detectivities on the order of 10 to the 13th cm sq rt Hz/W, a value which exceeds the best obtainable from existing solid-state detectors, have now been consistently obtained in Si and GaAs devices using high-capacitance LaF3 or composite LaF3/native-oxide insulating layers. The measured spectral response of representative samples is presented and discussed in detail together with a simple theory which accounts for the observed behavior. The response of an ideal MIS photocapacitor is also contrasted with that of both a conventional photoconductor and a p-i-n photodiode, and reasons for the superior performance of the MIS detectors are given. Finally, fundamental studies on the electrical, optical, and noise characteristics of the MIS structures are analyzed and discussed in the context of infrared-detector applications.

  12. The Houston Academy of Medicine--Texas Medical Center Library management information system.

    PubMed Central

    Camille, D; Chadha, S; Lyders, R A

    1993-01-01

    A management information system (MIS) provides a means for collecting, reporting, and analyzing data from all segments of an organization. Such systems are common in business but rare in libraries. The Houston Academy of Medicine-Texas Medical Center Library developed an MIS that operates on a system of networked IBM PCs and Paradox, a commercial database software package. The data collected in the system include monthly reports, client profile information, and data collected at the time of service requests. The MIS assists with enforcement of library policies, ensures that correct information is recorded, and provides reports for library managers. It also can be used to help answer a variety of ad hoc questions. Future plans call for the development of an MIS that could be adapted to other libraries' needs, and a decision-support interface that would facilitate access to the data contained in the MIS databases. PMID:8251972

  13. Complementary spin transistor using a quantum well channel.

    PubMed

    Park, Youn Ho; Choi, Jun Woo; Kim, Hyung-Jun; Chang, Joonyeon; Han, Suk Hee; Choi, Heon-Jin; Koo, Hyun Cheol

    2017-04-20

    In order to utilize the spin field effect transistor in logic applications, the development of two types of complementary transistors, which play roles of the n- and p-type conventional charge transistors, is an essential prerequisite. In this research, we demonstrate complementary spin transistors consisting of two types of devices, namely parallel and antiparallel spin transistors using InAs based quantum well channels and exchange-biased ferromagnetic electrodes. In these spin transistors, the magnetization directions of the source and drain electrodes are parallel or antiparallel, respectively, depending on the exchange bias field direction. Using this scheme, we also realize a complementary logic operation purely with spin transistors controlled by the gate voltage, without any additional n- or p-channel transistor.

  14. Late Quaternary chronostratigraphic framework of terraces and alluvium along the lower Ohio River, southwestern Indiana and western Kentucky, USA

    USGS Publications Warehouse

    Counts, Ronald C.; Murari, Madhav K.; Owen, Lewis A.; Mahan, Shannon; Greenan, Michele

    2015-01-01

    The lower Ohio River valley is a terraced fluvial landscape that has been profoundly influenced by Quaternary climate change and glaciation. A modern Quaternary chronostratigraphic framework was developed for the lower Ohio River valley using optically stimulated luminescence (OSL) dating and allostratigraphic mapping to gain insights into the nature of fluvial responses to glacial–interglacial/stadial–interstadial transitions and Holocene climate change. River deposits, T0 (youngest) to T7 (oldest), were mapped along a 75 km reach of the lower Ohio River and were dated using 46 OSL and 5 radiocarbon samples. The examination of cores combined with OSL and radiocarbon dating shows that fluvial sediments older than marine oxygen isotope stage (MIS) 2 are present only in the subsurface. Aggradation during MIS 6 (Illinoian glaciation) filled the valley to within ∼7 m of the modern floodplain, and by ∼114 ka (MIS 5e/Sangamon interglacial) the Ohio River had scoured the MIS 6 sediments to ∼22 m below the modern floodplain surface. There were no fluvial sediments in the valley with ages between MIS 5e and the middle of MIS 3. The MIS 3 ages (∼39 ka) and stratigraphic position of T5 deposits suggest the Ohio River aggraded 8–14 m during MIS 4 or MIS 3. Near the end of MIS 3, the Ohio River incised the mid Last Glacial (mid-Wisconsinan) deposits ∼10 m and began aggrading again by ∼30 ka. Aggradation continued into MIS 2, with maximum MIS 2 aggradation occurring before ∼21 ka, which is coincident with the global Last Glacial Maximum (LGM). As the Ohio River adjusted to changing fluxes in sediment load and discharge following the LGM, it formed a sequence of fill-cut terraces in the MIS 2 outwash that get progressively younger with decreasing elevation, ranging in age from ∼21 ka to ∼13 ka. From ∼14 ka to ∼13 ka the Ohio River rapidly incised ∼3 m to form a new terrace, and by ∼12 ka at the onset of the Holocene, the Ohio River established a meandering channel pattern. The river formed a broad floodplain surface from ∼12 ka to ∼6 ka, and then incised ∼1 m and formed a fill-cut terrace from ∼6 ka to ∼5 ka. After ∼5 ka, likely in response to mid-Holocene drought in North America, the Ohio River incised ∼5 m, and by ∼4 ka the river began aggrading again. The Ohio River has aggraded ∼4 m since aggradation began at ∼4 ka. The chronostratigraphic framework and reconstructed history developed here suggest that the lower Ohio River is highly sensitive to glacial–interglacial transitions and abrupt Holocene climate change and responds rapidly to these allogenic forcings.

  15. Evolvable circuit with transistor-level reconfigurability

    NASA Technical Reports Server (NTRS)

    Stoica, Adrian (Inventor); Salazar-Lazaro, Carlos Harold (Inventor)

    2004-01-01

    An evolvable circuit includes a plurality of reconfigurable switches, a plurality of transistors within a region of the circuit, the plurality of transistors having terminals, the plurality of transistors being coupled between a power source terminal and a power sink terminal so as to be capable of admitting power between the power source terminal and the power sink terminal, the plurality of transistors being coupled so that every transistor terminal to transistor terminal coupling within the region of the circuit comprises a reconfigurable switch.

  16. Learning from Action Evaluation of the Use of Multimedia Case Studies in Management Information Systems Courses

    ERIC Educational Resources Information Center

    Kawulich, Barbara B.

    2011-01-01

    This manuscript shares lessons learned from conducting an action evaluation of the use of multimedia case studies in Management Information Systems (MIS) courses. Three undergraduate MIS classes took part in the study. The purpose for using case studies in these classes was to teach students about the role of MIS in business. An action evaluation…

  17. 49 CFR Appendix H to Part 40 - DOT Drug and Alcohol Testing Management Information System (MIS) Data Collection Form

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ..., App. H Appendix H to Part 40—DOT Drug and Alcohol Testing Management Information System (MIS) Data... 49 Transportation 1 2010-10-01 2010-10-01 false DOT Drug and Alcohol Testing Management Information System (MIS) Data Collection Form H Appendix H to Part 40 Transportation Office of the Secretary...

  18. Design of a Model Management Information System (MIS) for California's Regional Occupational Centers and Programs. Final Report.

    ERIC Educational Resources Information Center

    Dick, James C.; And Others

    The management information system (MIS) development project for California's Regional Occupational Centers and Programs (ROC/Ps) was conducted in 3 phases over a 12-month period. Phase I involved a literature review and field study to match MIS design features and development strategy with existing conditions in ROC/Ps. A decision support system…

  19. Mapping the MIS Curriculum Based on Critical Skills of New Graduates: An Empirical Examination of IT Professionals

    ERIC Educational Resources Information Center

    Downey, James P.; McMurtrey, Mark E.; Zeltmann, Steven M.

    2008-01-01

    MIS curricula research almost always focuses on either curriculum issues or the critical skills required of new MIS graduates, rarely both. This study examines both by determining the critical skills required of new graduates, from the perspective of IT professionals in the field, then uniquely mapping those skills into a comprehensive yet…

  20. 49 CFR Appendix H to Part 40 - DOT Drug and Alcohol Testing Management Information System (MIS) Data Collection Form

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ..., App. H Appendix H to Part 40—DOT Drug and Alcohol Testing Management Information System (MIS) Data... 49 Transportation 1 2013-10-01 2013-10-01 false DOT Drug and Alcohol Testing Management Information System (MIS) Data Collection Form H Appendix H to Part 40 Transportation Office of the Secretary...

  1. 49 CFR Appendix H to Part 40 - DOT Drug and Alcohol Testing Management Information System (MIS) Data Collection Form

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ..., App. H Appendix H to Part 40—DOT Drug and Alcohol Testing Management Information System (MIS) Data... 49 Transportation 1 2014-10-01 2014-10-01 false DOT Drug and Alcohol Testing Management Information System (MIS) Data Collection Form H Appendix H to Part 40 Transportation Office of the Secretary...

  2. 49 CFR Appendix H to Part 40 - DOT Drug and Alcohol Testing Management Information System (MIS) Data Collection Form

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ..., App. H Appendix H to Part 40—DOT Drug and Alcohol Testing Management Information System (MIS) Data... 49 Transportation 1 2012-10-01 2012-10-01 false DOT Drug and Alcohol Testing Management Information System (MIS) Data Collection Form H Appendix H to Part 40 Transportation Office of the Secretary...

  3. 49 CFR Appendix H to Part 40 - DOT Drug and Alcohol Testing Management Information System (MIS) Data Collection Form

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ..., App. H Appendix H to Part 40—DOT Drug and Alcohol Testing Management Information System (MIS) Data... 49 Transportation 1 2011-10-01 2011-10-01 false DOT Drug and Alcohol Testing Management Information System (MIS) Data Collection Form H Appendix H to Part 40 Transportation Office of the Secretary...

  4. Anchorage loss due to Herbst mechanics-preventable through miniscrews?

    PubMed

    Bremen, Julia von; Ludwig, Björn; Ruf, Sabine

    2015-10-01

    To assess if mandibular incisor proclination and protrusion during treatment with the Herbst/multibracket appliance can be prevented through simple screws (MIs) anchorage. After a statistical power analysis, 12 Herbst patients with MIs (100% MIs survival) ligated to the Herbst/multibracket appliance to reinforce anchorage were investigated. A control group matched for gender and skeletal maturity treated without MIs anchorage was selected. Pre- and posttreatment cephalograms were analysed for overjet reduction, mandibular incisor proclination (IL/ML), protrusion (Ii-MLp) and intrusion (Ii-ML), as well as occlusal plane inclination (OP/ML) by a single-blinded examiner. No statistically significant differences between the two groups were found concerning overjet reduction, incisor protrusion- and intrusion or occlusal plane tilt. Although the MIs group generally showed less lower incisor proclination (4.8°) than the group without skeletal anchorage (6.5°), a large interindividual variation was observed. Interradicular MIs anchorage cannot prevent anchorage loss during Herbst treatment. For the individual patient, the amount of incisor proclination and protrusion remains unpredictable. © The Author 2014. Published by Oxford University Press on behalf of the European Orthodontic Society. All rights reserved. For permissions, please email: journals.permissions@oup.com.

  5. A 600-ka Arctic sea-ice record from Mendeleev Ridge based on ostracodes

    USGS Publications Warehouse

    Cronin, Thomas M.; Polyak, L.V.; Reed, D.; Kandiano, E. S.; Marzen, R. E.; Council, E. A.

    2013-01-01

    Arctic paleoceanography and sea-ice history were reconstructed from epipelagic and benthic ostracodes from a sediment core (HLY0503-06JPC, 800 m water depth) located on the Mendeleev Ridge, Western Arctic Ocean. The calcareous microfaunal record (ostracodes and foraminifers) covers several glacial/interglacial cycles back to estimated Marine Isotope Stage 13 (MIS 13, ∼500 ka) with an average sedimentation rate of ∼0.5 cm/ka for most of the stratigraphy (MIS 5–13). Results based on ostracode assemblages and an unusual planktic foraminiferal assemblage in MIS 11 dominated by a temperate-water species Turborotalita egelida show that extreme interglacial warmth, high surface ocean productivity, and possibly open ocean convection characterized MIS 11 and MIS 13 (∼400 and 500 ka, respectively). A major shift in western Arctic Ocean environments toward perennial sea ice occurred after MIS 11 based on the distribution of an ice-dwelling ostracode Acetabulastoma arcticum. Spectral analyses of the ostracode assemblages indicate sea ice and mid-depth ocean circulation in western Arctic Ocean varied primarily at precessional (∼22 ka) and obliquity (∼40 ka) frequencies.

  6. [Validation of French versions of magical ideation and perceptual aberrations questionnaires].

    PubMed

    Dumas, P; Bouafia, S; Gutknecht, C; Saoud, M; Daléry, J; d'Amato, T

    2000-01-01

    Chapman and colleagues have developed symptom-oriented scales based on Meehl's manual of schizotypy, such as the Social Anhedonia (SA) and Physical Anhedonia (PhA) Scales, the Magical Ideation Scale (MIS), and the Perceptual Aberration Scale (PAS). Whereas Chapman's scales of psychosis proneness are the most internationally used instruments for the assessment of schizotypy, some of them, such as MIS and PAS, were still not available in French. We reported here the validation study of the MIS and the PAS French versions that we had published previously. This study was conducted in a sample of 233 students (males: n = 108; females: n = 125; mean age: 21.17 +/- 1.47; mean educational level: 13.36 +/- 1.06). The French versions of the MIS and the PAS have high internal reliability (MIS: Cronbach's alpha = 0.85; PAS: Cronbach's alpha = 0.88). French norms are given for each of these scales. They are respectively 19/30 for the MIS and 17/35 for the PAS high cutoff scores without any difference when gender was considered. These results are very closed to those found by Chapman and colleagues for University of Wisconsin undergraduate students.

  7. A new ELSA time series of tephra layers and paleobotanical evidence from laminated Eifel maar sediments covering the entire last 120,000 years

    NASA Astrophysics Data System (ADS)

    Sirocko, Frank; Knapp, Hannes; Klee, Marlies; Rothacker, Leo; Kromer, Bernd

    2014-05-01

    The ELSA Project has drilled a total of 50 sediment cores (2000 m of laminated lake sediment) from Eifel maar lakes and dry maar structures during the last 15 years. These records have been dated using 7 different methods, including 370 14C dates. Ten records reveal the established palynological succession of trees during the Holocene down to the Laacher See Tephra, which is used for synchronization with seven more recently drilled laminated sediment cores, which all are 14C-dated too and analyzed for tephra, pollen and paleobotanical macroremains. The seven newly established records reveal a continuous MIS2 section with mosses, ostracods and characea oogonia. They show that the 28.000 - 40.000 BP has witnessed an open landscape dominated by grass, but with rhythmic spread of conifer trees following the Greenland interstadial/succession. Seeds of Ranunculae provide excellent material for 14C dating. Even deciduous trees are present in small amounts until 28.000 BP. The time from 48.000 to 40.000 BP is characterized by a pronounced transition from the open landscape to an early MIS3 spruce (Picea) dominated forest during Greenland Interstadial GI17-14. Modern man apparently arrived at the end of this principal vegetation change near 40,000 BP. Volcanic activity in the Eifel had a stable and pronounced recurrence from 55,000 - 30,000 BP every 4000 years, but commenced with the beginning of MIS2. This landscape evolution with a forested early MIS3 is quite different to peat and sediment records from Netherlands/ Northern Germany/Scandinavia/ Poland, but is similar to conditions in parts of Switzerland. We address the early MIS3 forest to the nearby continuously moist soils and warm conditions in the nearby Mosel valley, i.e. on those stands where wine is growing today, and which most likely had served as a local refugia even for deciduous trees during MIS4 and MIS3. The MIS5 sections of the presented ELSA records reach down at least to the beginning of MIS5d near 118,000 BP, probably even back into MIS5e. The oldest Ar/Ar dated ELSA records reach down to 480,000 BP.

  8. Insights into MIS 3 and 4 climate in the Alps from the Baumkirchen paleo-lake site: Results of pollen analysis

    NASA Astrophysics Data System (ADS)

    Barrett, Samuel; Drescher-Schneider, Ruth; Starnberger, Reinhard; Spötl, Christoph

    2016-04-01

    The well-known Baumkirchen site of western Austria has recently been the focus of a renewed research effort. New drilling has greatly extended the length of the known lacustrine sequence to over 250 m. Luminescence dating has corroborated the late MIS 3 radiocarbon dates for the upper part of the sequence and revealed two lake phases: the upper extending from late MIS 3 back to mid MIS 3, and the lower covering late MIS 4 or early MIS 3 back possibly as far as MIS 5a. X-ray fluorescence core scanning analysis confirmed the presence of two phases which have different geochemical signals, and provided a chemistry-based stratigraphy in the visually monotonous sediments. In these uniform sediments, the only clear indication of climatic conditions from the sediments themselves is a short sequence of ice-rafted debris corresponding to the end of MIS 4. However, given their age and location within the Alps, these sediments provide an important archive of Alpine climate in the last glacial cycle. We present new results from pollen analysis and discuss them in the context of previously reported findings. Due to high sedimentation rates, pollen counts were very low. However, two stadials and two interstadials were identified. The entire lower lake phase corresponding to MIS 4 was identified as a stadial, being characterised by a very low total pollen concentrations, a dominance of herb over tree pollen and significant reworking of pre-Quaternary forms and wood fragments. The upper lake phase contains two interstadials split by an intervening stadial. The interstadials are characterised by higher total pollen concentrations and proportion of woody species including the sporadic presence of relatively warm climate species with the upper of the two appearing better developed with these indicators more strongly expressed. This upper interstadial corresponds to the location of well dated plant remains putting its age around 35 ka cal BP, strongly suggesting a correlation to Greenland interstadial 7, while the correspondence of the lower interstadial is uncertain. Overall, the vegetation of the central Inn Valley during MIS 3 and 4 was dominated by steppe-like open-vegetation (consistent with earlier work from the upper part of the sequence) with tree stands (but not forests) establishing themselves during the interstadials.

  9. Foraminifera eco-biostratigraphy of the southern Evoikos outer shelf, central Aegean Sea, during MIS 5 to present

    NASA Astrophysics Data System (ADS)

    Drinia, Hara; Antonarakou, Assimina; Tsourou, Theodora; Kontakiotis, George; Psychogiou, Maria; Anastasakis, George

    2016-09-01

    The South Evoikos Basin is a marginal basin in the Aegean Sea which receives little terrigenous supply and its sedimentation is dominated by hemipelagic processes. Late Quaternary benthic and planktonic foraminifera from core PAG-155 are investigated in order to understand their response to the glacial-interglacial cycles in this region. The quantitative analysis of planktonic foraminifera, coupled with accelerator mass spectrometry (14C-AMS) radiocarbon date measurements, provide an integrated chrono-stratigraphic time framework over the last 90 ka (time interval between late Marine Isotopic Stages 5 and 1; MIS5-MIS1). The temporary appearance and disappearance as well as several abundance peaks in the quantitative distribution of selected climate-sensitive planktonic species allowed the identification of several eco-bioevents, useful to accurately mark the boundaries of the eco-biozones widely recognized in the Mediterranean records and used for large-scale correlations. The established bio-ecozonation scheme allows a detailed palaecological reconstruction for the late Pleistocene archive in the central Aegean, and furthermore provides a notable contribution for palaeoclimatic studies, facilitating intercorrelations between various oceanographic basins. The quantitative analyses of benthic foraminifera identify four distinct assemblages, namely Biofacies: Elphidium spp., Haynesina spp. Biofacies, characterized by neritic species, dominated during the transition from MIS 5 to MIS 4; Cassidulina laevigata/carinata Biofacies dominated till 42 ka (transgressive trend from MIS 4 to MIS 3); Bulimina gibba Biofacies dominated from 42 ka to 9.5 ka (extensive regression MIS 3,2 through lowstand and early transgression; beginning of MIS 1); Bulimina marginata, Uvigerina spp. Biofacies dominated from 9.5 ka to the present (late transgression through early highstand; MIS 1)., This study showed that the South Evoikos Basin which is characterized by its critical depths and connections to the open sea, and its small volume water masses that nourished foraminiferal assemblages, accurately records 5th-4th order sea level and climatic fluctuations. Especially, the basin's limited communication with the open ocean implies that any climatic signals will be recorded in an amplified fashion, and therefore this heightened sensitivity to the effects of climate variability further underlies the prominent role of such marginal basins in the understanding of the global climatic evolution.

  10. Glacial cycles and the growth and destruction of Alaska volcanoes

    NASA Astrophysics Data System (ADS)

    Coombs, M. L.; Calvert, A. T.; Bacon, C. R.

    2014-12-01

    Glaciers have affected profoundly the growth, collapse, preservation, and possibly, eruptive behavior of Quaternary stratovolcanoes in Alaska. Holocene alpine glaciers have acted as effective agents of erosion on volcanoes north of ~55 °N and especially north of 60 °N. Cook Inlet volcanoes are particularly vulnerable as they sit atop rugged intrusive basement as high as 3000 m asl. Holocene glaciers have swept away or covered most of the deposits and dome lavas of frequently active Redoubt (60.5 °N); carved through the flanks of Spurr's active vent, Crater Peak (61.3 °N); and all but obscured the edifice of Hayes (61.6 °N), whose Holocene eruptive history is known almost exclusively though far-traveled tephra and flowage deposits. Relationships between Pleistocene eruptive histories, determined by high-precision Ar-Ar dating of lava flows, and marine oxygen isotope stages (MIS) 2-8 (Bassinot et al., 1994, EPSL, v. 126, p. 91­-108) vary with a volcano's latitude, size, and elevation. At Spurr, 26 ages cluster in interglacial periods. At Redoubt, 28 ages show a more continual eruptive pattern from the end of MIS 8 to the present, with a slight apparent increase in output following MIS 6, and almost no preservation before 220 ka. Veniaminof (56.2 °N) and Emmons (55.5°N), large, broad volcanoes with bases near sea level, had voluminous eruptive episodes during the profound deglaciations after MIS 8 and MIS 6. At Akutan (54.1 °N), many late Pleistocene lavas show evidence for ice contact; ongoing dating will be able to pinpoint ice thicknesses. Furthest south and west, away from thick Pleistocene ice on the Alaska Peninsula and mainland, the Tanaga volcanic cluster (51.9 °N) has a relatively continuous eruptive record for the last 200 k.y. that shows no clear-cut correlation with glacial cycles, except a possible hiatus during MIS 6. Finally, significant edifice collapse features have been temporally linked with deglaciations. A ~10-km3 debris-avalanche deposit from Spurr directly overlies bedrock, suggesting that edifice collapse closely followed MIS 2. The geologic history of Veniaminof suggests possible massive edifice collapse following MIS 6. A stack of westward-dipping lavas and breccias on the east flank of Redoubt Volcano erupted during MIS 6, and may have also failed during the major deglaciation of MIS 5.5.

  11. Characteristics of enhanced-mode AlGaN/GaN MIS HEMTs for millimeter wave applications

    NASA Astrophysics Data System (ADS)

    Lee, Jong-Min; Ahn, Ho-Kyun; Jung, Hyun-Wook; Shin, Min Jeong; Lim, Jong-Won

    2017-09-01

    In this paper, an enhanced-mode (E-mode) AlGaN/GaN high electron mobility transistor (HEMT) was developed by using 4-inch GaN HEMT process. We designed and fabricated Emode HEMTs and characterized device performance. To estimate the possibility of application for millimeter wave applications, we focused on the high frequency performance and power characteristics. To shift the threshold voltage of HEMTs we applied the Al2O3 insulator to the gate structure and adopted the gate recess technique. To increase the frequency performance the e-beam lithography technique was used to define the 0.15 um gate length. To evaluate the dc and high frequency performance, electrical characterization was performed. The threshold voltage was measured to be positive value by linear extrapolation from the transfer curve. The device leakage current is comparable to that of the depletion mode device. The current gain cut-off frequency and the maximum oscillation frequency of the E-mode device with a total gate width of 150 um were 55 GHz and 168 GHz, respectively. To confirm the power performance for mm-wave applications the load-pull test was performed. The measured power density of 2.32 W/mm was achieved at frequencies of 28 and 30 GHz.

  12. Comprehensive dynamic on-resistance assessments in GaN-on-Si MIS-HEMTs for power switching applications

    NASA Astrophysics Data System (ADS)

    Chou, Po-Chien; Hsieh, Ting-En; Cheng, Stone; del Alamo, Jesús A.; Chang, Edward Yi

    2018-05-01

    This study comprehensively analyzed the reliability of trapping and hot-electron effects responsible for the dynamic on-resistance (Ron) of GaN-based metal–insulator–semiconductor high electron mobility transistors. Specifically, this study performed the following analyses. First, we developed the on-the-fly Ron measurement to analyze the effects of traps during stress. With this technique, the faster one (with a pulse period of 20 ms) can characterize the degradation; the transient behavior could be monitored accurately by such short measurement pulse. Then, dynamic Ron transients were investigated under different bias conditions, including combined off state stress conditions, back-gating stress conditions, and semi-on stress conditions, in separate investigations of surface- and buffer-, and hot-electron-related trapping effects. Finally, the experiments showed that the Ron increase in semi-on state is significantly correlated with the high drain voltage and relatively high current levels (compared with the off-state current), involving the injection of greater amount of hot electrons from the channel into the AlGaN/insulator interface and the GaN buffer. These findings provide a path for device engineering to clarify the possible origins for electron traps and to accelerate the development of emerging GaN technologies.

  13. Speleothem evidence for MIS 5c and 5a sea level above modern level at Bermuda

    NASA Astrophysics Data System (ADS)

    Wainer, Karine A. I.; Rowe, Mark P.; Thomas, Alexander L.; Mason, Andrew J.; Williams, Bruce; Tamisiea, Mark E.; Williams, Felicity H.; Düsterhus, André; Henderson, Gideon M.

    2017-01-01

    The history of sea level in regions impacted by glacio-isostasy provides constraints on past ice-sheet distribution and on the characteristics of deformation of the planet in response to loading. The Western North Atlantic-Caribbean region, and Bermuda in particular, is strongly affected by the glacial forebulge that forms as a result of the Laurentide ice-sheet present during glacial periods. The timing of growth of speleothems, at elevations close to sea level can provide records of minimum relative sea level (RSL). In this study we used U-Th dating to precisely date growth periods of speleothems from Bermuda which were found close to modern-day sea level. Results suggest that RSL at this location was above modern during MIS5e, MIS5c and MIS5a. These data support controversial previous indications that Bermudian RSL was significantly higher than RSL at other locations during MIS 5c and MIS 5a. We confirm that it is possible to explain a wide range of MIS5c-a relative sea levels observed across the Western North Atlantic-Caribbean in glacial isostatic adjustment models, but only with a limited range of mantle deformation constants. This study demonstrates the particular power of Bermuda as a gauge for response of the forebulge to glacial loading, and demonstrates the potential for highstands at this location to be significantly higher than in other regions, helping to explain the high sea levels observed for Bermuda from earlier highstands.

  14. Inflammation and nutritional status assessment by malnutrition inflammation score and its outcome in pre-dialysis chronic kidney disease patients.

    PubMed

    Jagadeswaran, D; Indhumathi, E; Hemamalini, A J; Sivakumar, V; Soundararajan, P; Jayakumar, M

    2018-01-09

    Malnutrition-inflammation complex syndrome (MICS), hyperhomocysteinemia, calcium and phosphate levels derangement have been predicted as important contributing factors for the progression of cardiovascular burden. Among patients with earlier stage of CKD, hypoalbuminaemia and inflammation deliberated as non-traditional cardiovascular risk factors, which add more burden to circulatory disease, mortality and rapid advancement to CKD stage 5. The aim of the study is to evaluate inflammation and nutritional status of CKD patients not on dialysis using Malnutrition inflammation score (MIS) and to verify the association with mortality in the follow-up period. In this prospective cohort study 129 (66 males, 63 females) pre-dialysis CKD patients enrolled between June 2013 to August 2014 and censored until March 2017. Malnutrition and Inflammation assessed using Malnutrition inflammation score. Blood urea nitrogen, serum creatinine, albumin, Interleukin - 6, highly sensitive C reactive protein (hsCRP), total cholesterol and anthropometric data were analyzed. The Malnutrition inflammation score in pre-dialysis CKD patients ranged from 0 to 18 with the median score of two. During 36 or more months of follow-up, there were 30 (23.2%) deaths, 35 (27%) patients initiated on hemodialysis, one (0.7%) patient was initiated on peritoneal dialysis, two (1.4%) patients underwent renal transplantation and two (1.4%) patients were lost for follow-up. In this study, 33% had varying degree of malnutrition and inflammation. Patients who had MIS ≥7 had significant increase in IL-6 (p = 0.003) and HsCRP levels (p < 0.001) when compared with other tertiles of MIS. ROC curve analysis of MIS showed 56.5% sensitivity and 81% specificity in predicting death rate (AUC 0.709; 95% CI 0.604-0.815, p < 0.001). Kaplan-Meier survival analysis showed MIS ≥7 had a strong association (log rank test, p < 0.001) with mortality during 36 and more months of follow-up time. In unadjusted analyses, MIS (HR 1.140; 95% CI 1.054-1.233; p < 0.05) and HsCRP (HR 2.369; 95% CI 1.779-3.154; p < 0.001) found to be predictors of mortality. MIS and HsCRP remained predictors of mortality even after adjustments. This study shows MIS is an important factor that determines mortality in pre-dialysis CKD patients during 36 and more months of follow-up time. Patients with MIS ≥7 have high risk for mortality and needs close monitoring. In clinical setting application of MIS has a greater utilization in pre-dialysis CKD patients. Further research with longitudinal assessment of MIS and its association with outcomes are warranted. Pre-dialysis CKD patients should be assessed for their nutritional status and inflammation using MIS regularly to prevent malnutrition and its associated complications through appropriate medical and nutritional intervention. Copyright © 2018 Elsevier Ltd and European Society for Clinical Nutrition and Metabolism. All rights reserved.

  15. Transistor-based interface circuitry

    DOEpatents

    Taubman, Matthew S [Richland, WA

    2007-02-13

    Among the embodiments of the present invention is an apparatus that includes a transistor, a servo device, and a current source. The servo device is operable to provide a common base mode of operation of the transistor by maintaining an approximately constant voltage level at the transistor base. The current source is operable to provide a bias current to the transistor. A first device provides an input signal to an electrical node positioned between the emitter of the transistor and the current source. A second device receives an output signal from the collector of the transistor.

  16. Transistor-based particle detection systems and methods

    DOEpatents

    Jain, Ankit; Nair, Pradeep R.; Alam, Muhammad Ashraful

    2015-06-09

    Transistor-based particle detection systems and methods may be configured to detect charged and non-charged particles. Such systems may include a supporting structure contacting a gate of a transistor and separating the gate from a dielectric of the transistor, and the transistor may have a near pull-in bias and a sub-threshold region bias to facilitate particle detection. The transistor may be configured to change current flow through the transistor in response to a change in stiffness of the gate caused by securing of a particle to the gate, and the transistor-based particle detection system may configured to detect the non-charged particle at least from the change in current flow.

  17. Investigation of the sensitivity of MIS-sensor to thermal decomposition products of cables insulation

    NASA Astrophysics Data System (ADS)

    Filipchuk, D. V.; Litvinov, A. V.; Etrekova, M. O.; Nozdrya, D. A.

    2017-12-01

    Sensitivity of the MIS-sensor to products of thermal decomposition of insulation and jacket of the most common types of cables is investigated. It is shown that hydrogen is evolved under heating the insulation to temperatures not exceeding 250 °C. Registration of the evolved hydrogen by the MIS-sensor can be used for detection of fires at an early stage.

  18. Mediterranean Outflow and surface water variability off southern Portugal during the early Pleistocene: A snapshot at Marine Isotope Stages 29 to 34 (1020-1135 ka)

    NASA Astrophysics Data System (ADS)

    Voelker, Antje H. L.; Salgueiro, Emilia; Rodrigues, Teresa; Jimenez-Espejo, Francisco J.; Bahr, André; Alberto, Ana; Loureiro, Isabel; Padilha, Maria; Rebotim, Andreia; Röhl, Ursula

    2015-10-01

    Centennial-to-millennial scale records from IODP Site U1387, drilled during IODP Expedition 339 into the Faro Drift at 558 m water depth, now allow evaluating the climatic history of the upper core of the Mediterranean Outflow (MOW) and of the surface waters in the northern Gulf of Cadiz during the early Pleistocene. This study focuses on the period from Marine Isotope Stages (MIS) 29 to 34, i.e. the interval surrounding extreme interglacial MIS 31. Conditions in the upper MOW reflect obliquity, precession and millennial-scale variations. The benthic δ18O signal follows obliquity with the exception of an additional, smaller δ18O peak that marks the MIS 32/31 transition. Insolation maxima (precession minima) led to poor ventilation and a sluggish upper MOW core, whereas insolation minima were associated with enhanced ventilation and often also increased bottom current velocity. Millennial-scale periods of colder sea-surface temperatures (SST) were associated with short-term maxima in flow velocity and better ventilation, reminiscent of conditions known from MIS 3. A prominent contourite layer, coinciding with insolation cycle 100, was formed during MIS 31 and represents one of the few contourites developing within an interglacial period. MIS 31 surface water conditions were characterized by an extended period (1065-1091 ka) of warm SST, but SST were not much warmer than during MIS 33. Interglacial to glacial transitions experienced 2 to 3 stadial/interstadial cycles, just like their mid-to-late Pleistocene counterparts. Glacial MIS 30 and 32 recorded periods of extremely cold (< 12 °C) SST that in their climatic impact were comparable with the Heinrich events of the mid and late Pleistocene. Glacial MIS 34, on the other hand, was a relative warm glacial period off southern Portugal. Overall, surface water and MOW conditions at Site U1387 show a strong congruence with Mediterranean climate, whereas millennial-scale variations are closely linked to North Atlantic circulation changes.

  19. Challenges of DHS and MIS to capture the entire pattern of malaria parasite risk and intervention effects in countries with different ecological zones: the case of Cameroon.

    PubMed

    Massoda Tonye, Salomon G; Kouambeng, Celestin; Wounang, Romain; Vounatsou, Penelope

    2018-04-06

    In 2011, the demographic and health survey (DHS) in Cameroon was combined with the multiple indicator cluster survey. Malaria parasitological data were collected, but the survey period did not overlap with the high malaria transmission season. A malaria indicator survey (MIS) was also conducted during the same year, within the malaria peak transmission season. This study compares estimates of the geographical distribution of malaria parasite risk and of the effects of interventions obtained from the DHS and MIS survey data. Bayesian geostatistical models were applied on DHS and MIS data to obtain georeferenced estimates of the malaria parasite prevalence and to assess the effects of interventions. Climatic predictors were retrieved from satellite sources. Geostatistical variable selection was used to identify the most important climatic predictors and indicators of malaria interventions. The overall observed malaria parasite risk among children was 33 and 30% in the DHS and MIS data, respectively. Both datasets identified the Normalized Difference Vegetation Index and the altitude as important predictors of the geographical distribution of the disease. However, MIS selected additional climatic factors as important disease predictors. The magnitude of the estimated malaria parasite risk at national level was similar in both surveys. Nevertheless, DHS estimates lower risk in the North and Coastal areas. MIS did not find any important intervention effects, although DHS revealed that the proportion of population with an insecticide-treated nets access in their household was statistically important. An important negative relationship between malaria parasitaemia and socioeconomic factors, such as the level of mother's education, place of residence and the household welfare were captured by both surveys. Timing of the malaria survey influences estimates of the geographical distribution of disease risk, especially in settings with seasonal transmission. In countries with different ecological zones and thus different seasonal patterns, a single survey may not be able to identify all high risk areas. A continuous MIS or a combination of MIS, health information system data and data from sentinel sites may be able to capture the disease risk distribution in space across different seasons.

  20. Stratigraphy and evolution of emerged Pleistocene reefs at the Red Sea coast of Sudan

    NASA Astrophysics Data System (ADS)

    Hamed, Basher; Bussert, Robert; Dominik, Wilhelm

    2016-02-01

    Emerged Pleistocene coral reefs constitute a prominent landform along the Red Sea coast of Sudan. They are well exposed with a thickness of up to 12 m and extend over a width of about 3 km parallel to the coastline. Four major reef units that represent different reef zones are distinguished. Unit 1 is located directly at the coastline and is assigned to the rock-reef rim, while unit 2 represents the reef-front zone. Unit 3 is attributed to the reef-flat zone and unit 4 to the back-reef zone. The stratigraphic position and age of the four units respectively the facies zones are based on field relationships and δ18O analysis. Results of δ18O analysis of coral, gastropod and bivalve samples were correlated to previous age dating of correlative reefs in Sudan and other parts of the Red Sea region. Estimation of reef ages was mainly based on δ18O values of the reef-front zone (unit 2) and the observed sedimentary succession of the reefs. δ18O values of two Porites coral samples from the reef-front zone strongly suggest equivalent ages of 120 and 122 ka that correspond to marine isotope stage MIS 5.5. Based on δ18O values and the field relationship to the reef-front zone, ages of reef-flat zone (unit 3) and back-reef zone (unit 4) could be assigned to MIS 9 and MIS 7 respectively. MIS 5.1 is suggested for the reef-rock rim (unit 1). The relationship of the reef zones to individual MIS might be explained by the predominance of a specific zone during a certain stage, while other facies were less well developed and/or later eroded by wave action. The reef unit most distal from the recent coastline formed during interglacial stage MIS 7, while former studies assign this unit to interglacial stage MIS 9. Unique flourishing, high diversity and excellent preservation of corals in the back-reef unit of MIS 7 reflect growth in troughs landward of the oldest reef-flat formed during previous interglacial stage MIS 9.

  1. Comparison of the costs of nonoperative care to minimally invasive surgery for sacroiliac joint disruption and degenerative sacroiliitis in a United States commercial payer population: potential economic implications of a new minimally invasive technology

    PubMed Central

    Ackerman, Stacey J; Polly, David W; Knight, Tyler; Schneider, Karen; Holt, Tim; Cummings, John

    2014-01-01

    Introduction Low back pain is common and treatment costly with substantial lost productivity and lost wages in the working-age population. Chronic low back pain originating in the sacroiliac (SI) joint (15%–30% of cases) is commonly treated with nonoperative care, but new minimally invasive surgery (MIS) options are also effective in treating SI joint disruption. We assessed whether the higher initial MIS SI joint fusion procedure costs were offset by decreased nonoperative care costs from a US commercial payer perspective. Methods An economic model compared the costs of treating SI joint disruption with either MIS SI joint fusion or continued nonoperative care. Nonoperative care costs (diagnostic testing, treatment, follow-up, and retail pharmacy pain medication) were from a retrospective study of Truven Health MarketScan® data. MIS fusion costs were based on the Premier’s Perspective™ Comparative Database and professional fees on 2012 Medicare payment for Current Procedural Terminology code 27280. Results The cumulative 3-year (base-case analysis) and 5-year (sensitivity analysis) differentials in commercial insurance payments (cost of nonoperative care minus cost of MIS) were $14,545 and $6,137 per patient, respectively (2012 US dollars). Cost neutrality was achieved at 6 years; MIS costs accrued largely in year 1 whereas nonoperative care costs accrued over time with 92% of up front MIS procedure costs offset by year 5. For patients with lumbar spinal fusion, cost neutrality was achieved in year 1. Conclusion Cost offsets from new interventions for chronic conditions such as MIS SI joint fusion accrue over time. Higher initial procedure costs for MIS were largely offset by decreased nonoperative care costs over a 5-year time horizon. Optimizing effective resource use in both nonoperative and operative patients will facilitate cost-effective health care delivery. The impact of SI joint disruption on direct and indirect costs to commercial insurers, health plan beneficiaries, and employers warrants further consideration. PMID:24904218

  2. Viability after myocardial infarction: can it be assessed within five minutes by low-dose dynamic iodine-123-iodophenylpentadecanoic acid imaging with a multicrystal gamma camera?

    PubMed

    Murray, G L; Schad, N; Bush, A J

    1997-04-01

    Although positron emission tomography (PET) assesses myocardial viability (V) accurately, a rapid, inexpensive substitute is needed. Therefore, the authors developed a low-dose (1 mCi) Iodine-123-Iodophenylpentadecanoic Acid (IPPA) myocardial viability scan requiring analysis of only the first three minutes of data acquired at rest with a standard multicrystal gamma camera. Twenty-one patients > 2 weeks after myocardial infarction (MI) (24 MIs, 10 anterior, 14 inferoposterior, 21 akinetic or dyskinetic) had cardiac catheterization and resting IPPA imaging. V was determined by either transmural myocardial biopsy during coronary bypass surgery (12 patients, 14 MIs) or reinjection tomographic thallium scan (9 patients, 10 MIs), and 50% of MIs were viable. The IPPA variables analyzed were: time to initial left ventricular (LV) uptake in the region of interest (ROI), the ratio of three-minute uptake in the ROI to three-minute LV uptake, three-minute clearing (counts/pixel) in the ROI (decrease in IPPA after initial uptake), and three-minute accumulation (increase in IPPA after initial uptake) in the ROI. Rules for detecting V were generated and applied to 10 healthy volunteers to determine normalcy. While three-minute uptake in nonviable MIs was only 67% of volunteers (P < 0.0001) and 75% of viable MIs, uptake alone identified only 50% of viable MIs and 75% of nonviable MIs. IPPA clearing, however, was > or = 13.5 counts/pixel in 10/12 (83%) of viable MIs, and IPPA accumulation > or = 6.75 counts/pixel identified one more viable MI, for a sensitivity for V of 11/12 (92%), with a specificity of 11/12 (92%), and a 100% normalcy rate. The authors conclude low-dose IPPA (five-minute acquisition with analysis of the first three minutes of data) has potential for providing rapid, inexpensive V data after MI. Since newer multicrystal cameras are mobile, IPPA scans can be done in emergency rooms or coronary care units generating information that might be useful in decisions regarding thrombolysis, angioplasty, or bypass surgery.

  3. Artemisinin resistance containment project in Thailand. (I): Implementation of electronic-based malaria information system for early case detection and individual case management in provinces along the Thai-Cambodian border.

    PubMed

    Khamsiriwatchara, Amnat; Sudathip, Prayuth; Sawang, Surasak; Vijakadge, Saowanit; Potithavoranan, Thanapon; Sangvichean, Aumnuyphan; Satimai, Wichai; Delacollette, Charles; Singhasivanon, Pratap; Lawpoolsri, Saranath; Kaewkungwal, Jaranit

    2012-07-29

    The Bureau of Vector-borne Diseases, Ministry of Public Health, Thailand, has implemented an electronic Malaria Information System (eMIS) as part of a strategy to contain artemisinin resistance. The attempt corresponds to the WHO initiative, funded by the Bill & Melinda Gates Foundation, to contain anti-malarial drug resistance in Southeast Asia. The main objective of this study was to demonstrate the eMIS' functionality and outputs after implementation for use in the Thailand artemisinin-resistance containment project. The eMIS had been functioning since 2009 in seven Thai-Cambodian border provinces. The eMIS has covered 61 malaria posts/clinics, 27 Vector-borne Disease Units covering 12,508 hamlets at risk of malaria infections. The eMIS was designed as an evidence-based and near real-time system to capture data for early case detection, intensive case investigation, monitoring drug compliance and on/off-site tracking of malarial patients, as well as collecting data indicating potential drug resistance among patients. Data captured by the eMIS in 2008-2011 were extracted and presented. The core functionalities of the eMIS have been utilized by malaria staff at all levels, from local operational units to ministerial management. The eMIS case detection module suggested decreasing trends during 2009-2011; the number of malaria cases detected in the project areas over the years studied were 3818, 2695, and 2566, with sero-positive rates of 1.24, 0.98, and 1.16%, respectively. The eMIS case investigation module revealed different trends in weekly Plasmodium falciparum case numbers, when classified by responsible operational unit, local and migrant status, and case-detection type. It was shown that most Thai patients were infected within their own residential district, while migrants were infected either at their working village or from across the border. The data mapped in the system suggested that P. falciparum-infected cases and potential drug-resistant cases were scattered mostly along the border villages. The mobile technology application has detected different follow-up rates, with particularly low rates among seasonal and cross-border migrants. The eMIS demonstrated that it could capture essential data from individual malaria cases at local operational units, while effectively being used for situation and trend analysis at upper-management levels. The system provides evidence-based information that could contribute to the control and containment of resistant parasites. Currently, the eMIS is expanding beyond the Thai-Cambodian project areas to the provinces that lie along the Thai-Myanmar border.

  4. Evidence for the timing of sea-level events during MIS 3

    NASA Astrophysics Data System (ADS)

    Siddall, M.

    2005-12-01

    Four large sea-level peaks of millennial-scale duration occur during MIS 3. In addition smaller peaks may exist close to the sensitivity of existing methods to derive sea level during these periods. Millennial-scale changes in temperature during MIS 3 are well documented across much of the planet and are linked in some unknown, yet fundamental way to changes in ice volume / sea level. It is therefore highly likely that the timing of the sea level events during MIS 3 will prove to be a `Rosetta Stone' for understanding millennial scale climate variability. I will review observational and mechanistic arguments for the variation of sea level on Antarctic, Greenland and absolute time scales.

  5. Hand preference, magical thinking and left-right confusion.

    PubMed

    Jaspers-Fayer, Fern; Peters, Michael

    2005-03-01

    Several reports suggest a significant correlation between hand preference quotients and Magical Ideation Scale (MIS) scores, such that individuals with mixed preferences have higher MIS scores. In a sample of 156 male and 257 female undergraduate university students no significant correlation was found between MIS scores and hand preference; hand preference being defined in numerous ways, and using short and long hand preference questionnaires to assess handedness. An index of left-right confusion was significantly related to MIS score, but only in females. We suggest that the role of subjects' response style and general approach to filling out questionnaires should be fully explored before "neurological" causes of links between hand preference and other questionnaire-assessed behavioural variables are invoked.

  6. MIS capacitor studies on silicon carbide single crystals

    NASA Technical Reports Server (NTRS)

    Kopanski, J. J.

    1990-01-01

    Cubic SIC metal-insulator-semiconductor (MIS) capacitors with thermally grown or chemical-vapor-deposited (CVD) insulators were characterized by capacitance-voltage (C-V), conductance-voltage (G-V), and current-voltage (I-V) measurements. The purpose of these measurements was to determine the four charge densities commonly present in an MIS capacitor (oxide fixed charge, N(f); interface trap level density, D(it); oxide trapped charge, N(ot); and mobile ionic charge, N(m)) and to determine the stability of the device properties with electric-field stress and temperature. The section headings in the report include the following: Capacitance-voltage and conductance-voltage measurements; Current-voltage measurements; Deep-level transient spectroscopy; and Conclusions (Electrical characteristics of SiC MIS capacitors).

  7. Volatile-rich komatiitic and picritic melt inclusions in Cr-spinel beach sand from Gorgona Island, Colombia

    NASA Astrophysics Data System (ADS)

    Shimizu, K.; Shimizu, N.; Suzuki, K.; Tatsumi, Y.; Komiya, T.; Maruyama, S.

    2007-12-01

    Volatile content of komatiite is a key to constrain thermal evolution of the deep Earth. We report volatile contents with major and trace element compositions of melt inclusions (MIs) in chromian spinel (Cr-spinel) from beach sands of Gorgona Island, Colombia. Gorgona Island is ~90 Ma volcanic island, where picrites and the world-youngest komatiites occur. As Cr-spinel is dense and rigid oxide mineral that crystallizes only at early stages of crystallization, it is considered to be a superior container for retaining primitive melt, even including volatiles. Volatile (H2O, CO2, S, F and Cl) and trace element (K2O, Sr, Y, Zr, Nb, Ba, La, Ce, Sm, Dy, Yb) compositions of ~80 MIs were analyzed by SIMS (Cameca-1280 and 3f, respectively) at WHOI. MIs in the Cr-spinel from Gorgona Is. are classified into three types by their host Cr-spinel compositions such as low-Ti (P-type), high-Ti with high-Cr# (BK-type) and high-Ti with low-Cr# (K-type). MIs of P-type, BK-type and K-type are mostly in compositional ranges of picrite, high TiO2 komatiite (some basalt) and low TiO2 komatiite in Gorgona Island, respectively. Water content of P-type MIs is variable, ranging from 0.05 to 0.9 wt%, whereas those of BK and K-type MIs are limited (< 0.1 wt%). On the other hand, CO2 contents of BK-type and K- type MIs are highly scattered (40 to 4200 ppm), whereas that of P-type is relatively constant at ~200 ppm. All MIs with high CO2 content (>500 ppm) do not contain (shrinkage) bubbles and many of them are low in K2O. H2O/K2O, CO2/K2O, S/K2O and F/K2O ratios are positively correlated with Y/Sr ratios, indicating degassing trends of melt at crystallization, magma mixing and/or assimilation. Undegassed H2O/K2O, CO2/K2O, S/K2O and F/K2O ratios of komatiitic (picritic) melt are estimated to be ~10 (~40), ~80 (n.d.), ~7(~3) and ~1(~0.5), respectively, which are much higher than those estimated for the depleted source mantle of the MORB [1.6, 0.7, 1.6 and 0.2, respectively; Salters, V. & Stracke, A. (2004), Composition of the depleted mantle. Geochem. Geophys. Geosys. 5 (2003GC000597)]. The results suggest that Gorgona komatiite and picrite magmas were derived from volatile-rich sources. CO2 degassing might also have contributed to eruption of high-density magmas to the surface. In addition, H2O, S, F and Cl contents in MIs in olivine from a picrite were identical to those of P-type MIs in Cr-spinel, but CO2 in olivine-hosted MIs were considerably lower (~50 ppm) than those in Cr-spinel. This indicates that entrapment pressure for MIs in Cr-spinel is likely to be greater than that for MIs in olivine. Therefore, in order to evaluate the volatile contents of undegassed magmas from oceanic islands, melt inclusions in Cr-spinel beach sand could be very useful.

  8. Lake level fluctuations and catchment dynamics at Lake Ohrid (Macedonia, Albania) during MIS6 and MIS5

    NASA Astrophysics Data System (ADS)

    Francke, Alexander; Wagner, Bernd; Just, Janna; Sadori, Laura; Masi, Alessia; Vogel, Hendrik; Lindhorst, Katja; Krastel, Sebastian; Dosseto, Anthony; Rothacker, Leo; Leicher, Niklas; Gromig, Raphael

    2016-04-01

    Lake Ohrid, presumably the oldest lake of Europe located at the border of Macedonia and Albania, is about 30 km long, 15 km wide, and up to 290 m deep. In 2013, an ICDP deep drilling campaign was carried out under the umbrella of the Scientific Collaboration on Past Speciation Conditions in Lake Ohrid (SCOPSCO) project. At the main drill site (DEEP) in the central part of Lake Ohrid, the uppermost 568 m from a total sediment fill of ca. 700 m were recovered. Initial data from core catcher material indicate that the sediment sequence covers more than 1.2 million years. An age model, which is based on 11 tephrostratigragphic tie points and on tuning of biogeochemical proxy data versus orbital parameters reveals that that the upper 247 m of the DEEP site sequence cover the time period between 637 ka (MIS16) and the present. Inhere, we present sedimentological, (bio-)geochemical, environmental magnetic, and pollen data for the time period between MIS6 (191 ka) and MIS5 (71 ka). The data imply that MIS6 was one of the most severe glacial periods, while MIS5 was likely one of the more pronounced interglacial during the past 637 kyrs. The repercussions of these high amplitude climatic and environmental variations during this period are recorded in the sedimentological archive of Lake Ohrid. Previous studies based on hydro-acoustic and sediment core data from the northeastern part of the lake basin have shown that the lake level of Lake Ohrid was likely 60 m lower during MIS6. The ˜60 m lower lake level at Lake Ohrid during MIS6 can at least partly be explained by the ongoing subsidence, which persists in the basin until today. However, in the DEEP site sediments, the MIS6/MIS5 transition occurs at ca. 50 m sediment depth. This implies that climate-induced lake level fluctuation at Lake Ohrid are less severe compared for example to Lake Van (Turkey), were a 260 m lower lake level has been reported for the Younger Dryas. The imprint of the environmental variations between 191 ka and 71 ka can also be seen in the catchment dynamics around the lake. Extraordinary high sedimentation rates, high clastic and negligible authigenic matter concentrations in DEEP site sediments during MIS6 imply enhanced erosion in the catchment. Thereby, elemental ratios (Zr/K) and environmental magnetic data (S-ratio) suggest that predominantly the products of chemical weathered, K-depleted old soils were transported into the lake. In contrast, a low sedimentation rate despite high authigenic matter concentrations during MIS5 implies less erosion in the catchment. In order to obtain more information about the catchment dynamics at Lake Ohrid, future studies will encompass the analyses of uranium and lithium isotopes. U isotopes (234U and 238U) can be used to assess the balance between deep and shallow erosion, while Li isotopes (7Li and 6Li) can inform on the extent of chemical weathering in the sediment source area. The application of these tools on a Late Glacial to Holocene record from Lake Dojran (Macedonia, Greece) has recently shown that climatic perturbations (8.2 and 4.2 cooling event) and anthropogenic land use have a direct impact on the catchment dynamics.

  9. Low electron mobility of field-effect transistor determined by modulated magnetoresistance

    NASA Astrophysics Data System (ADS)

    Tauk, R.; Łusakowski, J.; Knap, W.; Tiberj, A.; Bougrioua, Z.; Azize, M.; Lorenzini, P.; Sakowicz, M.; Karpierz, K.; Fenouillet-Beranger, C.; Cassé, M.; Gallon, C.; Boeuf, F.; Skotnicki, T.

    2007-11-01

    Room temperature magnetotransport experiments were carried out on field-effect transistors in magnetic fields up to 10 T. It is shown that measurements of the transistor magnetoresistance and its first derivative with respect to the gate voltage allow the derivation of the electron mobility in the gated part of the transistor channel, while the access/contact resistances and the transistor gate length need not be known. We demonstrate the potential of this method using GaN and Si field-effect transistors and discuss its importance for mobility measurements in transistors with nanometer gate length.

  10. Multiple-channel detection of cellular activities by ion-sensitive transistors

    NASA Astrophysics Data System (ADS)

    Machida, Satoru; Shimada, Hideto; Motoyama, Yumi

    2018-04-01

    An ion-sensitive field-effect transistor to record cellular activities was demonstrated. This field-effect transistor (bio transistor) includes cultured cells on the gate insulator instead of gate electrode. The bio transistor converts a change in potential underneath the cells into variation of the drain current when ion channels open. The bio transistor has high detection sensitivity to even minute variations in potential utilizing a subthreshold swing region. To open ion channels, a reagent solution (acetylcholine) was added to a human-originating cell cultured on the bio transistor. The drain current was successfully decreased with the addition of acetylcholine. Moreover, we attempted to detect the opening of ion channels using a multiple-channel measurement circuit containing several bio transistors. As a consequence, the drain current distinctly decreased only after the addition of acetylcholine. We confirmed that this measurement system including bio transistors enables to observation of cellular activities sensitively and simultaneously.

  11. A transistor based on 2D material and silicon junction

    NASA Astrophysics Data System (ADS)

    Kim, Sanghoek; Lee, Seunghyun

    2017-07-01

    A new type of graphene-silicon junction transistor based on bipolar charge-carrier injection was designed and investigated. In contrast to many recent studies on graphene field-effect transistor (FET), this device is a new type of bipolar junction transistor (BJT). The transistor fully utilizes the Fermi level tunability of graphene under bias to increase the minority-carrier injection efficiency of the base-emitter junction in the BJT. Single-layer graphene was used to form the emitter and the collector, and a p-type silicon was used as the base. The output of this transistor was compared with a metal-silicon junction transistor ( i.e. surface-barrier transistor) to understand the difference between a graphene-silicon junction and metal-silicon Schottky junction. A significantly higher current gain was observed in the graphene-silicon junction transistor as the base current was increased. The graphene-semiconductor heterojunction transistor offers several unique advantages, such as an extremely thin device profile, a low-temperature (< 110 °C) fabrication process, low cost (no furnace process), and high-temperature tolerance due to graphene's stability. A transistor current gain ( β) of 33.7 and a common-emitter amplifier voltage gain of 24.9 were achieved.

  12. Exposure dating and glacial reconstruction at Mt. Field, Tasmania, Australia, identifies MIS 3 and MIS 2 glacial advances and climatic variability

    NASA Astrophysics Data System (ADS)

    Mackintosh, A. N.; Barrows, T. T.; Colhoun, E. A.; Fifield, L. K.

    2006-05-01

    Tasmania is important for understanding Quaternary climatic change because it is one of only three areas that experienced extensive mid-latitude Southern Hemisphere glaciation and it lies in a dominantly oceanic environment at a great distance from Northern Hemisphere ice sheet feedbacks. We applied exposure dating using 36Cl to an extensive sequence of moraines from the last glacial at Mt. Field, Tasmania. Glaciers advanced at 41-44 ka during Marine oxygen Isotope Stage (MIS) 3 and at 18 ka during MIS 2. Both advances occurred in response to an ELA lowering greater than 1100 m below the present-day mean summer freezing level, and a possible temperature reduction of 7-8°C. Deglaciation was rapid and complete by ca. 16 ka. The overall story emerging from studies of former Tasmanian glaciers is that the MIS 2 glaciation was of limited extent and that some glaciers were more extensive during earlier parts of the last glacial cycle. Copyright

  13. MIS-11 duration key to disappearance of the Greenland ice sheet

    NASA Astrophysics Data System (ADS)

    Robinson, Alexander; Alvarez-Solas, Jorge; Calov, Reinhard; Ganopolski, Andrey; Montoya, Marisa

    2017-07-01

    Palaeo data suggest that Greenland must have been largely ice free during Marine Isotope Stage 11 (MIS-11). However, regional summer insolation anomalies were modest during this time compared to MIS-5e, when the Greenland ice sheet likely lost less volume. Thus it remains unclear how such conditions led to an almost complete disappearance of the ice sheet. Here we use transient climate-ice sheet simulations to simultaneously constrain estimates of regional temperature anomalies and Greenland's contribution to the MIS-11 sea-level highstand. We find that Greenland contributed 6.1 m (3.9-7.0 m, 95% credible interval) to sea level, ~7 kyr after the peak in regional summer temperature anomalies of 2.8 °C (2.1-3.4 °C). The moderate warming produced a mean rate of mass loss in sea-level equivalent of only around 0.4 m per kyr, which means the long duration of MIS-11 interglacial conditions around Greenland was a necessary condition for the ice sheet to disappear almost completely.

  14. Screening-Engineered Field-Effect Solar Cells

    DTIC Science & Technology

    2012-01-01

    virtually any semiconductor, including the promising but hard-to- dope metal oxides, sulfides, and phosphides.3 Prototype SFPV devices have been...MIS interface. Unfortu- nately, MIS cells, though sporting impressive efficiencies,4−6 typically have short operating lifetimes due to surface state...instability at the MIS interface.7 Methods aimed at direct field- effect “ doping ” of semiconductors, in which the voltage is externally applied to a gate

  15. Modification of electrical properties of Au/n-type InP Schottky diode with a high-k Ba0.6Sr0.4TiO3 interlayer

    NASA Astrophysics Data System (ADS)

    Thapaswini, P. Prabhu; Padma, R.; Balaram, N.; Bindu, B.; Rajagopal Reddy, V.

    2016-05-01

    Au/Ba0.6Sr0.4TiO3 (BST)/n-InP metal/insulator/semiconductor (MIS) Schottky diodes have been analyzed by current-voltage (I-V) and capacitance-voltage (C-V) measurements. The surface morphology of the BST films on InP is fairly smooth. The Au/BST/n-InP MIS Schottky diode shows better rectification ratio and low leakage current compared to the conventional Au/n-InP metal-semiconductor (MS) Schottky diode. Higher barrier height is achieved for the MIS Schottky diode compared to the MS Schottky diode. The Norde and Cheung's methods are employed to determine the barrier height, ideality factor and series resistance. The interface state density (NSS) is determined from the forward bias I-V data for both the MS and MIS Schottky diodes. Results reveal that the NSS of the MIS Schottky diode is lower than that of the MS Schottky diode. The Poole-Frenkel emission is found dominating the reverse current in both Au/n-InP MS and Au/BST/n-InP MIS Schottky diodes, indicating the presence of structural defects and trap levels in the dielectric film.

  16. Design of an integrated master-slave robotic system for minimally invasive surgery.

    PubMed

    Li, Jianmin; Zhou, Ningxin; Wang, Shuxin; Gao, Yuanqian; Liu, Dongchun

    2012-03-01

    Minimally invasive surgery (MIS) robots are commonly used in hospitals and medical centres. However, currently available robotic systems are very complicated and huge, greatly raising system costs and the requirements of operating rooms. These disadvantages have become the major impediments to the expansion of MIS robots. An integrated MIS robotic system is proposed based on the analysis of advantages and disadvantages of different MIS robots. In the proposed system, the master manipulators, slave manipulators, image display device and control system have been designed as a whole. Modular design is adopted for the control system for easy maintenance and upgrade. The kinematic relations between the master and the slave are also investigated and embedded in software to realize intuitive movements of hand and instrument. Finally, animal experiments were designed to test the effectiveness of the robot. The robot realizes natural hand-eye movements between the master and the slave to facilitate MIS operations. The experimental results show that the robot can realize similar functions to those of current commercialized robots. The integrated design simplifies the robotic system and facilitates use of the robot. Compared with the commercialized robots, the proposed MIS robot achieves similar functions and features but with a smaller size and less weight. Copyright © 2011 John Wiley & Sons, Ltd.

  17. Taphonomic problems in reconstructing sea-level history from the late Quaternary marine terraces of Barbados

    USGS Publications Warehouse

    Muhs, Daniel; Simmons, Kathleen R.

    2017-01-01

    Although uranium series (U-series) ages of growth-position fossil corals are important to Quaternary sea-level history, coral clast reworking from storms can yield ages on a terrace dating to more than one high-sea stand, confounding interpretations of sea-level history. On northern Barbados, U-series ages corals from a thick storm deposit are not always younger with successively higher stratigraphic positions, but all date to the last interglacial period (~127 ka to ~112 ka), Marine Isotope Substage (MIS) 5.5. The storm deposit ages are consistent with the ages of growth-position corals found at the base of the section and at landward localities on this terrace. Thus, in this case, analysis of only a few corals would not have led to an error in interpreting sea-level history. In contrast, a notch cut into older Pleistocene limestone below the MIS 5.5 terrace contains corals that date to both MIS 5.5 (~125 ka) and MIS 5.3 (~108 ka). We infer that the notch formed during MIS 5.3 and the MIS 5.5 corals are reworked. Similar multiple ages of corals on terraces have been reported elsewhere on Barbados. Thus, care must be taken in interpreting U-series ages of corals that are reported without consideration of taphonomy.

  18. Comparison of the surgical outcomes of minimally invasive and open surgery for octogenarian and older compared to younger gastric cancer patients: a retrospective cohort study.

    PubMed

    Liu, Chien-An; Huang, Kuo-Hung; Chen, Ming-Huang; Lo, Su-Shun; Li, Anna Fen-Yau; Wu, Chew-Wun; Shyr, Yi-Ming; Fang, Wen-Liang

    2017-06-12

    As life expectancy continues to increase around the world, the use of minimally invasive surgery (MIS) could be beneficial for octogenarian and older gastric cancer patients. A total of 359 gastric cancer patients who underwent curative surgery between March 2011 and March 2015 were enrolled; 80 of these patients (22.2%) were octogenarians and older. Surgical approaches included MIS (50 laparoscopic and 65 robotic) and open surgery (n = 244). Surgical outcomes of MIS and open surgery in octogenarian and older patients were compared with younger patients. Among octogenarian and older patients, relative to open surgery (n = 53), MIS (n = 27) was associated with less operative blood loss, a shorter postoperative hospital stay and similar rates of surgical complications and mortality. For MIS (n = 115), octogenarian and older patients exhibited similar postoperative outcomes to those of younger patients. For open surgery (n = 244), relative to younger patients, octogenarian and older patients experienced longer postoperative hospital stays, a higher rate of wound infection and a higher incidence of pneumonia. MIS for gastric cancer is beneficial and can be performed safely in octogenarian and older patients.

  19. Climate and hydrology of the last interglaciation (MIS 5) in Owens Basin, California: Isotopic and geochemical evidence from core OL-92

    USGS Publications Warehouse

    Li, H.-C.; Bischoff, J.L.; Ku, T.-L.; Zhu, Z.-Y.

    2004-01-01

    ??18O, ??13C, total organic carbon, total inorganic carbon, and acid-leachable Li, Mg and Sr concentrations on 443 samples from 32 to 83 m depth in Owens Lake core OL-92 were analyzed to study the climatic and hydrological conditions between 60 and 155 ka with a resolution of ???200 a. The multi-proxy data show that Owens Lake overflowed during wet/cold conditions of marine isotope stages (MIS) 4, 5b and 6, and was closed during the dry/warm conditions of MIS 5a, c and e. The lake partially overflowed during MIS 5d. Our age model places the MIS 4/5 boundary at ca 72.5 ka and the MIS 5/6 boundary (Termination II) at ca 140 ka, agreeing with the Devils Hole chronology. The diametrical precipitation intensities between the Great Basin (cold/wet) and eastern China (cold/dry) on Milankovitch time scales imply a climatic teleconnection across the Pacific. It also probably reflects the effect of high-latitude ice sheets on the southward shifts of both the summer monsoon frontal zone in eastern Asia and the polar jet stream in western North America during glacial periods. ?? 2003 Elsevier Ltd. All rights reserved.

  20. ProMIS augmented reality training of laparoscopic procedures face validity.

    PubMed

    Botden, Sanne M B I; Buzink, Sonja N; Schijven, Marlies P; Jakimowicz, Jack J

    2008-01-01

    Conventional video trainers lack the ability to assess the trainee objectively, but offer modalities that are often missing in virtual reality simulation, such as realistic haptic feedback. The ProMIS augmented reality laparoscopic simulator retains the benefit of a traditional box trainer, by using original laparoscopic instruments and tactile tasks, but additionally generates objective measures of performance. Fifty-five participants performed a "basic skills" and "suturing and knot-tying" task on ProMIS, after which they filled out a questionnaire regarding realism, haptics, and didactic value of the simulator, on a 5-point-Likert scale. The participants were allotted to 2 experience groups: "experienced" (>50 procedures and >5 sutures; N = 27), and "moderately experienced" (<50 procedures and <5 sutures; N = 28). General consensus among all participants, particularly the experienced, was that ProMIS is a useful tool for training (mean: 4.67, SD: 0.48). It was considered very realistic (mean: 4.44, SD: 0.66), with good haptics (mean: 4.10, SD: 0.97) and didactic value (mean 4.10, SD: 0.65). This study established the face validity of the ProMIS augmented reality simulator for "basic skills" and "suturing and knot-tying" tasks. ProMIS was considered a good tool for training in laparoscopic skills for surgical residents and surgeons.

  1. Marine Isotope Stage 11 : The Role of Co2, Insolation and Antarctica Ice Sheet On This Interglacial

    NASA Astrophysics Data System (ADS)

    Raynaud, D.; Loutre, M. F.; Ritz, C.; Barnola, J.-M.; Berger, A.; Chappellaz, J.; Jouzel, J.; Lipenkov, V.; Petit, J.-R.; Vimeux, F.

    The Marine Isotopic Stage 11 (MIS 11), around 400kyr BP ago, has been suggested as an analogue for a future climate under natural forcing because of the similar condi- tions of orbitally driven insolation during this interglacial period and the one covering the Holocene and the near future. There are many open questions about unusual MIS 11 climatic conditions (length of the interglacial, temperature, sea level, marine car- bonate system), as recorded in different marine and continental records. The Antarctic Vostok ice core provides the only atmospheric record extending back to MIS 11 and we use it to discuss the Antarctic temperature, the atmospheric CO2 concentration and the ice sheet stability in the central part of East Antarctica during this interglacial. The unique nature of the Vostok atmospheric record leads us to use the available Vos- tok data to drive climate and ice sheet models for MIS 11. A model of intermediate complexity (LLN-2D model) is used to investigate the sensitivity of the simulated MIS 11 deglaciation to the interplay between insolation and CO2. It is shown that the length of the simulated interglacial depends strongly on the phasing between these two climate forcings. We also investigate the response of the Antarctic Ice Sheet to changing climate through simulations performed with the LGGE 3-D ice sheet model. The results indicate that sea level stands during MIS 11 as high as 20 m. above present level, as suggested by different elevated marine terraces, cannot be explained, except by assuming that MIS 11 was very dry over Antarctica.

  2. MIS Score: Prediction Model for Minimally Invasive Surgery.

    PubMed

    Hu, Yuanyuan; Cao, Jingwei; Hou, Xianzeng; Liu, Guangcun

    2017-03-01

    Reports suggest that patients with spontaneous intracerebral hemorrhage (ICH) can benefit from minimally invasive surgery, but the inclusion criterion for operation is controversial. This article analyzes factors affecting the 30-day prognoses of patients who have received minimally invasive surgery and proposes a simple grading scale that represents clinical operation effectiveness. The records of 101 patients with spontaneous ICH presenting to Qianfoshan Hospital were reviewed. Factors affecting their 30-day prognosis were identified by logistic regression. A clinical grading scale, the MIS score, was developed by weighting the independent predictors based on these factors. Univariate analysis revealed that the factors that affect 30-day prognosis include Glasgow coma scale score (P < 0.01), age ≥80 years (P < 0.05), blood glucose (P < 0.01), ICH volume (P < 0.01), operation time (P < 0.05), and presence of intraventricular hemorrhage (P < 0.001). Logistic regression revealed that the factors that affect 30-day prognosis include Glasgow coma scale score (P < 0.05), age (P < 0.05), ICH volume (P < 0.01), and presence of intraventricular hemorrhage (P < 0.05). The MIS score was developed accordingly; 39 patients with 0-1 MIS scores had favorable prognoses, whereas only 9 patients with 2-5 MIS scores had poor prognoses. The MIS score is a simple grading scale that can be used to select patients who are suited for minimal invasive drainage surgery. When MIS score is 0-1, minimal invasive surgery is strongly recommended for patients with spontaneous cerebral hemorrhage. The scale merits further prospective studies to fully determine its efficacy. Copyright © 2016 Elsevier Inc. All rights reserved.

  3. Prognostic factors associated with the success rates of posterior orthodontic miniscrew implants: A subgroup meta-analysis.

    PubMed

    Hong, Sung-Bin; Kusnoto, Budi; Kim, Eun-Jeong; BeGole, Ellen A; Hwang, Hyeon-Shik; Lim, Hoi-Jeong

    2016-03-01

    To systematically review previous studies and to assess, via a subgroup meta-analysis, the combined odds ratio (OR) of prognostic factors affecting the success of miniscrew implants (MIs) inserted into the buccal posterior region. Three electronic searches that were limited to articles on clinical human studies using MIs that were published in English prior to March 2015 were conducted. The outcome measure was the success of MIs. Patient factors included age, sex, and jaw of insertion (maxilla vs. mandible), while the MI factors included length and diameter. A meta-analysis was performed on 17 individual studies. The quality of each study was assessed for non-randomized studies and quantified using the Newcastle-Ottawa Scale. The meta-analysis outcome was a combined OR. Subgroup and sensitivity analyses based on the study design, study quality, and sample size of miniscrews implanted were performed. Significantly higher success rates were revealed for MIs inserted in the maxilla, for patients ≥ 20 years of age, and for long MIs (≥ 8 mm) and MIs with a large diameter (> 1.4 mm). All subgroups acquired homogeneity, and the combined OR of the prospective studies (OR, 3.67; 95% confidence interval [CI], 2.10-6.44) was significantly higher in the maxilla than that in the retrospective studies (OR, 2.10; 95% CI, 1.60-2.74). When a treatment plan is made, these risk factors, i.e. jaw of insertion, age, MI length, and MI diameter, should be taken into account, while sex is not critical to the success of MIs.

  4. Comparison of Accuracy between Side-Cutting Instruments and Front-Cutting Instruments in Minimally Invasive Total Knee Arthroplasty.

    PubMed

    Pinsornsak, Piya; Harnroongroj, Thos

    2016-11-01

    The specialized instrument system used in minimally invasive surgery (MIS) has been developed for reducing soft tissue trauma in total knee arthroplasty (TKA). Compared with front-cutting MIS instruments, side-cutting quadriceps sparing MIS instruments have the advantage of creating a smaller incision and causing fewer traumas to the quadriceps tendon. However, the accuracy of side-cutting instruments concerns surgeons in prosthesis malalignment. To compare the accuracy of side-cutting quadriceps sparing instruments versus front-cutting instruments in MIS-TKA. In this prospective randomized controlled study, we compared the accuracy of side-cutting quadriceps sparing instruments versus the front-cutting instruments used in MIS-TKA. Sixty knees were included in the study, with 30 knees in each group. All the operations were performed by single surgeon. Coronal alignment (tibiofemoral angle, lateral distal femoral angle, and medial proximal tibial angle), and sagittal alignment (femoral component flexion and tibial posterior slope) were measured and compared. Tibiofemoral angle, lateral distal femoral angle, and medial proximal tibial angle, all of which are considered in the assessment of acceptable coronal radiographic alignment, were not different between groups (p = 0.353, 0.500, and 0.177, respectively). However, side-cutting quadriceps sparing instruments produced less acceptable sagittal radiographic alignment, femoral component flexion (63% vs. 93%, p = 0.005), and tibial posterior slope (73% vs. 93%, p = 0.04). Side-cutting quadriceps sparing MIS-TKA instruments had similar accuracy to front-cutting MIS-TKA instruments for coronal alignment but is less accurate for sagittal alignment.

  5. Electrical and carrier transport properties of the Au/Y2O3/n-GaN metal-insulator-semiconductor (MIS) diode with rare-earth oxide interlayer

    NASA Astrophysics Data System (ADS)

    Venkata Prasad, C.; Rajagopal Reddy, V.; Choi, Chel-Jong

    2017-04-01

    The electrical and transport properties of rare-earth Y2O3 on n-type GaN with Au electrode have been investigated by current-voltage and capacitance-voltage techniques at room temperature. The Au/Y2O3/n-GaN metal-insulator-semiconductor (MIS) diode shows a good rectification behavior compared to the Au/n-GaN metal-semiconductor (MS) diode. Statistical analysis showed that a mean barrier height (BH) and ideality factor are 0.78 eV and 1.93, and 0.96 eV and 2.09 for the Au/n-GaN MS and Au/Y2O3/n-GaN MIS diodes, respectively. Results indicate that the high BH is obtained for the MIS diode compared to the MS diode. The BH, ideality factor and series resistance are also estimated by Cheung's function and Norde method. From the forward current-voltage data, the interface state density ( N SS) is estimated for both the MS and MIS Schottky diodes, and found that the estimated N SS is lower for the MIS diode compared to the MS diode. The results reveal that the introduction of Y2O3 interlayer facilitated the reduction of N SS of the Au/n-GaN interface. Experimental results suggest that the Poole-Frenkel emission is a dominant conduction mechanism in the reverse bias region of both Au/n-GaN MS and Au/Y2O3/n-GaN MIS diodes.

  6. The role of minimally invasive spine surgery in the management of pyogenic spinal discitis

    PubMed Central

    Turel, Mazda K; Kerolus, Mena; Deutsch, Harel

    2017-01-01

    Background: Diagnostic yields for spondylodiscitis from CT guided biopsy is low. In the recent years, minimally invasive surgery (MIS) has shown to have a low morbidity and faster recovery. For spinal infections, MIS surgery may offer an opportunity for early pain control while obtaining a higher diagnostic yield than CT-guided biopsies. The aim of this study was to review our patients who underwent MIS surgery for spinal infection and report outcomes. Methods: A retrospective review of seven patients who underwent MIS decompression and/or discectomy in the setting of discitis, osteomyelitis, spondylodiscitis, and/or an epidural abscess was identified. Patient data including symptoms, visual analog score (VAS), surgical approach, antibiotic regimen, and postoperative outcomes were obtained. Results: Of the 7 patients, 5 patients had lumbar infections and two had thoracic infections. All seven patients improved in VAS immediately after surgery and at discharge. The average VAS improved by 4.4 ± 1.9 points. An organism was obtained in 6 of the 7 (85%) patients by the operative cultures. All patients made an excellent clinical recovery without the need for further spine surgery. All patients who received postoperative imaging on follow-up showed complete resolution or dramatically improved magnetic resonance imaging changes. The follow-up ranged from 2 to 9 months. Conclusions: MIS surgery provides an opportunity for early pain relief in patients with discitis, osteomyelitis, spondylodiscitis, and/or epidural abscess by directly addressing the primary cause of pain. MIS surgery for discitis provides a higher diagnostic yield to direct antibiotic treatment. MIS surgery results in good long-term recovery. PMID:28250635

  7. Biogeochemistry of a submerged groundwater seep ecosystem in Lake Huron near karst region of Alpena, MI

    NASA Astrophysics Data System (ADS)

    Kinsman-Costello, L. E.; Dick, G.; Sheik, C.; Burton, G. A.; Sheldon, N. D.

    2015-12-01

    Submerged groundwater seeps in Lake Huron establish ecosystems with distinctive geochemical conditions. In the Middle Island Sinkhole (MIS), a 23-m deep seep, groundwater seepage establishes low O2 (< 4 mg L-1), high sulfate (6 mM) conditions, in which a purple cyanobacteria-dominated mat thrives. The mat is capable of anoxygenic photosynthesis, oxygenic photosynthesis, and chemosynthesis. Within the top 3 cm of the mat-water interface, hydrogen sulfide concentrations increase to 1-7 mM. Little is known about the structure and function of microbes within organic-rich, high-sulfide sediments beneath the mat. Using pore water and sediment geochemical characterization along with microbial community analysis, we elucidated relationships between microbial community structure and ecosystem function along vertical gradients. In sediment pore waters, biologically reactive solutes (SO42-, NH4+, PO43-, and CH4) displayed steep vertical gradients, reflecting biological and geochemical functioning. In contrast, more conservative ions (Ca+2, Mg+2, Na+, and Cl-), did not change significantly with depth in MIS sediments, indicating groundwater influence in the sediment profile. MIS sediments contained more organic matter than typical Lake Huron sediments, and were generally higher in nutrients, metals, and sulfur (acid volatile sulfide). Using the Illumina MiSeq platform we detected 14,127 unique operational taxonomic units across sediment and surface mat samples. Microbial community composition in the MIS was distinctly different from non-groundwater affected areas at similar depth nearby in Lake Huron (ANOSIM, R= 0.74, p=0.002). MIS sediment communities were more diverse that MIS surface mat communities and changed with depth into sediments. MIS sediment community composition was related to several geochemical variables, including organic matter and multiple indicators of phosphorus availability. Elucidating the structure and function of microbial consortia in MIS, a highly unique and environmentally vulnerable ecosystem, provides a rare opportunity to understand relationships between microbial species and their environment and may provide insights into the evolution of life under ancient low-oxygen, high-sulfur conditions.

  8. Comparative effectiveness of open versus minimally invasive sacroiliac joint fusion.

    PubMed

    Ledonio, Charles Gt; Polly, David W; Swiontkowski, Marc F; Cummings, John T

    2014-01-01

    The mainstay of sacroiliac joint disruption/degenerative sacroiliitis therapy has been nonoperative management. This nonoperative management often includes a regimen of physical therapy, chiropractic treatment, therapeutic injections, and possibly radiofrequency ablation at the discretion of the treating physician. When these clinical treatments fail, sacroiliac joint fusion has been recommended as the standard treatment. Open and minimally invasive (MIS) surgical techniques are typical procedures. This study aims to compare the perioperative measures and Oswestry Disability Index (ODI) outcomes associated with each of these techniques. A comparative retrospective chart review of patients with sacroiliac joint fusion and a minimum of 1 year of follow-up was performed. Perioperative measures and ODI scores were compared using the Fisher's exact test and two nonparametric tests, ie, the Mann-Whitney U test and the Wilcoxon signed-rank test. The results are presented as percent or median with range, as appropriate. Forty-nine patients from two institutions underwent sacroiliac joint fusion between 2006 and 2012. Ten patients were excluded because of incomplete data, leaving 39 evaluable patients, of whom 22 underwent open and 17 underwent MIS sacroiliac joint fusion. The MIS group was significantly older (median age 66 [39-82] years) than the open group (median age 51 [34-74] years). Surgical time and hospital stay were significantly shorter in the MIS group than in the open group. Preoperative ODI was significantly greater in the open group (median 64 [44-78]) than in the MIS group (median 53 [14-84]). Postoperative improvement in ODI was statistically significant within and between groups, with MIS resulting in greater improvement. The open and MIS sacroiliac joint fusion techniques resulted in statistically and clinically significant improvement for patients with degenerative sacroiliitis refractory to nonoperative management. However, the number of patients reaching the minimal clinically important difference and those showing overall improvement were greater in the MIS group.

  9. Comparative effectiveness of open versus minimally invasive sacroiliac joint fusion

    PubMed Central

    Ledonio, Charles GT; Polly, David W; Swiontkowski, Marc F; Cummings, John T

    2014-01-01

    Background The mainstay of sacroiliac joint disruption/degenerative sacroiliitis therapy has been nonoperative management. This nonoperative management often includes a regimen of physical therapy, chiropractic treatment, therapeutic injections, and possibly radiofrequency ablation at the discretion of the treating physician. When these clinical treatments fail, sacroiliac joint fusion has been recommended as the standard treatment. Open and minimally invasive (MIS) surgical techniques are typical procedures. This study aims to compare the perioperative measures and Oswestry Disability Index (ODI) outcomes associated with each of these techniques. Methods A comparative retrospective chart review of patients with sacroiliac joint fusion and a minimum of 1 year of follow-up was performed. Perioperative measures and ODI scores were compared using the Fisher’s exact test and two nonparametric tests, ie, the Mann–Whitney U test and the Wilcoxon signed-rank test. The results are presented as percent or median with range, as appropriate. Results Forty-nine patients from two institutions underwent sacroiliac joint fusion between 2006 and 2012. Ten patients were excluded because of incomplete data, leaving 39 evaluable patients, of whom 22 underwent open and 17 underwent MIS sacroiliac joint fusion. The MIS group was significantly older (median age 66 [39–82] years) than the open group (median age 51 [34–74] years). Surgical time and hospital stay were significantly shorter in the MIS group than in the open group. Preoperative ODI was significantly greater in the open group (median 64 [44–78]) than in the MIS group (median 53 [14–84]). Postoperative improvement in ODI was statistically significant within and between groups, with MIS resulting in greater improvement. Conclusion The open and MIS sacroiliac joint fusion techniques resulted in statistically and clinically significant improvement for patients with degenerative sacroiliitis refractory to nonoperative management. However, the number of patients reaching the minimal clinically important difference and those showing overall improvement were greater in the MIS group. PMID:24940087

  10. The Sexual Function Questionnaire's Medical Impact Scale (SFQ-MIS): validation among a sample of first-time mothers.

    PubMed

    Jawed-Wessel, Sofia; Schick, Vanessa; Herbenick, Debby

    2013-11-01

    Changes in sexual function can be difficult to capture, especially when an attempt is made to assess the effects of pregnancy or childbirth on the sexual function of first-time mothers. Commonly used sexual function measures are limited and fail to account for pregnancy or birth in assessment of function. The purpose of this study was to explore the utility of the Sexual Function Questionnaire Medical Impact Scale (SFQ-MIS) in assessing impact of childbirth on sexual function among first-time mothers with infants aged one year or younger. A total of 255 women completed a cross-sectional, web-based survey. Exploratory factor analysis was utilized to assess the factor structure of the SFQ-MIS scores in this sample. Variations in SFQ-MIS scores based upon participant characteristics were conducted to further evaluate the SFQ-MIS scores. SFQ-MIS score was the primary measure of interest. Factors related to pregnancy and childbirth, such as mode of delivery, infant date of birth, last menstrual period, need for an episiotomy or perineal stitches, breastfeeding status, and score on the Perceived Stress Scale, were also assessed in order to further evaluate the validity and predictive capacity of the SFQ-MIS. Results indicated one factor that accounted for 58.27% of the variance in impact on sexual function due to childbirth. Cronbach's α coefficient for all five items was acceptable (0.82). Women who were breastfeeding (P<0.05), those who had received perineal stitches after a vaginal delivery (P<0.05), and those who reported no sexual activity in the past month (P < 0.001) experienced significantly greater impact than those who were not breastfeeding, those who had not required stitches, and those who had been sexually active in the past month. The SFQ-MIS appears to be a useful and valid indicator of changes in sexual function following childbirth, such as those related to arousal, desire, and orgasm. © 2013 International Society for Sexual Medicine.

  11. Detection of desmoplastic melanoma with dermoscopy and reflectance confocal microscopy.

    PubMed

    Maher, N G; Solinas, A; Scolyer, R A; Puig, S; Pellacani, G; Guitera, P

    2017-12-01

    Desmoplastic melanoma (DM) is frequently misdiagnosed clinically and often associated with melanoma in situ (MIS). To improve the detection of DM using dermoscopy and reflectance confocal microscopy (RCM). A descriptive analysis of DM dermoscopy features and a case-control study within a melanoma population for RCM feature evaluation was performed blindly, using data obtained between 2005 and 2015. After retrospectively identifying all DM cases with RCM data over the study period (n = 16), a control group of non-DM melanoma patients with RCM data, in a ratio of at least 3 : 1, was selected. The control group was matched by age and primary tumour site location, divided into non-DM invasive melanomas (n = 27) and MIS (n = 27). Invasive melanomas were selected according to the melanoma subtypes associated with the DM cases. The main outcomes were the frequency of melanoma-specific features on dermoscopy for DM; and the odds ratios of RCM features to distinguish DM from MIS and/or other invasive melanomas; or MIS from the combined invasive melanoma group. At least one of the 14 melanoma-specific features evaluated on dermoscopy was found in 100% of DMs (n = 15 DM with dermoscopy). Known RCM melanoma predictors were commonly found in the DMs, such as pagetoid cells (100%) and cell atypia (100%). The RCM feature of spindle cells in the superficial dermis was more common in DM compared with the entire melanoma control group (OR 3.82, 95% CI 1.01-14.90), and particularly compared to MIS (OR 5.48, 95% CI 1.11-32.36). Nucleated cells in the dermis and the RCM correlate of dermal inflammation were also significant RCM features favouring DM over MIS, as well as invasive melanoma over MIS. Dermoscopy and RCM may be useful tools for the identification of DM. Certain RCM features may help distinguish DM from MIS and other invasive melanomas. Larger studies are warranted. © 2017 European Academy of Dermatology and Venereology.

  12. Lithic technological responses to Late Pleistocene glacial cycling at Pinnacle Point Site 5-6, South Africa

    PubMed Central

    Brown, Kyle S.; Oestmo, Simen; Pereira, Telmo; Ranhorn, Kathryn L.; Schoville, Benjamin J.; Marean, Curtis W.

    2017-01-01

    There are multiple hypotheses for human responses to glacial cycling in the Late Pleistocene, including changes in population size, interconnectedness, and mobility. Lithic technological analysis informs us of human responses to environmental change because lithic assemblage characteristics are a reflection of raw material transport, reduction, and discard behaviors that depend on hunter-gatherer social and economic decisions. Pinnacle Point Site 5–6 (PP5-6), Western Cape, South Africa is an ideal locality for examining the influence of glacial cycling on early modern human behaviors because it preserves a long sequence spanning marine isotope stages (MIS) 5, 4, and 3 and is associated with robust records of paleoenvironmental change. The analysis presented here addresses the question, what, if any, lithic assemblage traits at PP5-6 represent changing behavioral responses to the MIS 5-4-3 interglacial-glacial cycle? It statistically evaluates changes in 93 traits with no a priori assumptions about which traits may significantly associate with MIS. In contrast to other studies that claim that there is little relationship between broad-scale patterns of climate change and lithic technology, we identified the following characteristics that are associated with MIS 4: increased use of quartz, increased evidence for outcrop sources of quartzite and silcrete, increased evidence for earlier stages of reduction in silcrete, evidence for increased flaking efficiency in all raw material types, and changes in tool types and function for silcrete. Based on these results, we suggest that foragers responded to MIS 4 glacial environmental conditions at PP5-6 with increased population or group sizes, ‘place provisioning’, longer and/or more intense site occupations, and decreased residential mobility. Several other traits, including silcrete frequency, do not exhibit an association with MIS. Backed pieces, once they appear in the PP5-6 record during MIS 4, persist through MIS 3. Changing paleoenvironments explain some, but not all temporal technological variability at PP5-6. PMID:28355257

  13. Effect of minimally invasive surgery fellowship on residents' operative experience.

    PubMed

    Altieri, Maria S; Frenkel, Catherine; Scriven, Richard; Thornton, Deborah; Halbert, Caitlin; Talamini, Mark; Telem, Dana A; Pryor, Aurora D

    2017-01-01

    There is an increased need for surgical trainees to acquire advanced laparoscopic skills as laparoscopy becomes the standard of care in many areas of general surgery. Since the introduction of minimally invasive surgery (MIS) fellowships, there has been a continuing debate as to whether these fellowships adversely affect general surgery resident exposure to laparoscopic cases. The aim of our study was to examine whether the introduction of an MIS fellowship negatively impacts general surgery residents' experience at a single academic center. We describe the changes following establishment of MIS fellowship at an academic center. Resident case log system from the Accreditation Council for Graduate Medical Education was queried to obtain all PGY 1-5 resident operative case logs. Two-year time period preceding and following the institution of an MIS fellowship at our institution in 2012 was compared. P values less than 0.05 were considered statistically significant. Following initiation of the MIS fellowship, an MIS service was established. The service comprised of a fellow, midlevel resident, and intern. Operative experience was examined. From 2010-2012 to 2012-2014, residents logged a total of 272 and 585 complex laparoscopic cases, respectively. There were 43 residents from 2010 to 2013 and 44 residents from 2013 to 2014. When the two time periods were compared, a trend of increased numbers for all procedures was noted, except laparoscopic GYN/genito-urinary procedures. Average percent increase in complex general surgery procedures was 249 ± 179.8 %. Following establishment of a MIS fellowship, reported cases by residents were higher or similar to those reported nationally for laparoscopic procedures. Institution of an MIS fellowship had a favorable effect on general surgery resident operative education at a single academic training center. Residents may benefit from the presence of a fellowship at an academic center because they are able to participate in an increased number of complex laparoscopic cases.

  14. The Last Interglacial in the Levant: Perspective from the ICDP Dead Sea Deep Drill Core

    NASA Astrophysics Data System (ADS)

    Goldstein, S. L.; Torfstein, A.; Stein, M.; Kushnir, Y.; Enzel, Y.; Haug, G. H.

    2014-12-01

    Sediments recovered by the ICDP Dead Sea Deep Drilling Project provide a new perspective on the climate history of the Levant during the last interglacial period MIS5. They record the extreme impacts of an intense interglacial characterized by stronger insolation, warmer mean global temperatures, and higher sea-levels than the Holocene. Results show both extreme hyper-aridity during MIS5e, including an unprecedented drawdown of Dead Sea water levels, and the impacts of a strong precession-driven African monsoon responsible for a major sapropel event (S5) in the eastern Mediterranean. Hyper-arid conditions at the beginning of MIS5e prior to S5 (~132-128 ka) are evidenced by halite deposition, indicating declining Dead Sea lake levels. Surprisingly, the hyper-arid phase is interrupted during the MIS5e peak (~128-120 ka), coinciding with the S5 sapropel, which is characterized by a thick (23 m) section of silty detritus (without any halite) whose provenance indicates southern-sourced wetness in the watershed. Upon weakening of the S5 monsoon (~120-115 ka), the return of extreme aridity resulted in an unprecedented lake level drawdown, reflected by massive salt deposition, and followed by a sediment hiatus (~115-100 ka) indicating prolonged low lake level. The resumption of section follows classic Levant patterns with more wetness during cooler MIS5b and hyper-aridity during warmer MIS5a. The ICDP core provides the first evidence for a direct linkage between an intense precession-driven African monsoon and wetness at the high subtropical latitude (~30N) of the Dead Sea watershed. Combined with coeval deposition of Negev speleothems and travertines, and calcitification of Red Sea corals, the evidence indicates a wet climatic corridor that could facilitate homo sapiens migration out of Africa during the MIS5e peak. In addition, the MIS 5e hyper-arid intervals may provide an important cautionary analogue for the impact of future warming on regional water resources.

  15. Lithic technological responses to Late Pleistocene glacial cycling at Pinnacle Point Site 5-6, South Africa.

    PubMed

    Wilkins, Jayne; Brown, Kyle S; Oestmo, Simen; Pereira, Telmo; Ranhorn, Kathryn L; Schoville, Benjamin J; Marean, Curtis W

    2017-01-01

    There are multiple hypotheses for human responses to glacial cycling in the Late Pleistocene, including changes in population size, interconnectedness, and mobility. Lithic technological analysis informs us of human responses to environmental change because lithic assemblage characteristics are a reflection of raw material transport, reduction, and discard behaviors that depend on hunter-gatherer social and economic decisions. Pinnacle Point Site 5-6 (PP5-6), Western Cape, South Africa is an ideal locality for examining the influence of glacial cycling on early modern human behaviors because it preserves a long sequence spanning marine isotope stages (MIS) 5, 4, and 3 and is associated with robust records of paleoenvironmental change. The analysis presented here addresses the question, what, if any, lithic assemblage traits at PP5-6 represent changing behavioral responses to the MIS 5-4-3 interglacial-glacial cycle? It statistically evaluates changes in 93 traits with no a priori assumptions about which traits may significantly associate with MIS. In contrast to other studies that claim that there is little relationship between broad-scale patterns of climate change and lithic technology, we identified the following characteristics that are associated with MIS 4: increased use of quartz, increased evidence for outcrop sources of quartzite and silcrete, increased evidence for earlier stages of reduction in silcrete, evidence for increased flaking efficiency in all raw material types, and changes in tool types and function for silcrete. Based on these results, we suggest that foragers responded to MIS 4 glacial environmental conditions at PP5-6 with increased population or group sizes, 'place provisioning', longer and/or more intense site occupations, and decreased residential mobility. Several other traits, including silcrete frequency, do not exhibit an association with MIS. Backed pieces, once they appear in the PP5-6 record during MIS 4, persist through MIS 3. Changing paleoenvironments explain some, but not all temporal technological variability at PP5-6.

  16. X-band T/R switch with body-floating multi-gate PDSOI NMOS transistors

    NASA Astrophysics Data System (ADS)

    Park, Mingyo; Min, Byung-Wook

    2018-03-01

    This paper presents an X-band transmit/receive switch using multi-gate NMOS transistors in a silicon-on-insulator CMOS process. For low loss and high power handling capability, floating body multi-gate NMOS transistors are adopted instead of conventional stacked NMOS transistors, resulting in 53% reduction of transistor area. Comparing to the stacked NMOS transistors, the multi gate transistor shares the source and drain region between stacked transistors, resulting in reduced chip area and parasitics. The impedance between bodies of gates in multi-gate NMOS transistors is assumed to be very large during design and confirmed after measurement. The measured input 1 dB compression point is 34 dBm. The measured insertion losses of TX and RX modes are respectively 1.7 dB and 2.0 dB at 11 GHz, and the measured isolations of TX and RX modes are >27 dB and >20 dB in X-band, respectively. The chip size is 0.086 mm2 without pads, which is 25% smaller than the T/R switch with stacked transistors.

  17. A prospective, multi-institutional comparative effectiveness study of lumbar spine surgery in morbidly obese patients: does minimally invasive transforaminal lumbar interbody fusion result in superior outcomes?

    PubMed

    Adogwa, Owoicho; Carr, Kevin; Thompson, Paul; Hoang, Kimberly; Darlington, Timothy; Perez, Edgar; Fatemi, Parastou; Gottfried, Oren; Cheng, Joseph; Isaacs, Robert E

    2015-05-01

    Obese and morbidly obese patients undergoing lumbar spinal fusion surgery are a challenge to the operating surgeon. Minimally invasive transforaminal lumbar interbody fusion (MIS-TLIF) and open-TLIF have been performed for many years with good results; however, functional outcomes after lumbar spine surgery in this subgroup of patients remain poorly understood. Furthermore, whether index MIS-TLIF or open-TLIF for the treatment of degenerative disc disease or spondylolisthesis in morbidly obese results in superior postoperative functional outcomes remains unknown. A total of 148 (MIS-TLIF: n = 40, open-TLIF: n = 108) obese and morbidly obese patients undergoing index lumbar arthrodesis for low back pain and/or radiculopathy between January 2003 and December 2010 were selected from a multi-institutional prospective data registry. We collected and analyzed data on patient demographics, postoperative complications, back pain, leg pain, and functional disability over 2 years. Patients completed the Oswestry Disability Index (ODI), Medical Outcomes Study Short-Form 36 (SF-36), and back and leg pain numerical rating scores before surgery and then at 12 and 24 months after surgery. Clinical outcomes and complication rates were compared between both patient cohorts. Compared with preoperative status, Visual Analog Scale (VAS) back and leg pain, ODI, and SF-36 physical component score/mental component score were improved in both groups. Both MIS-TLIF and open-TLIF patients showed similar 2-year improvement in VAS for back pain (MIS-TLIF: 2.42 ± 3.81 vs. open-TLIF: 2.33 ± 3.67, P = 0.89), VAS for leg pain (MIS-TLIF: 3.77 ± 4.53 vs. open-TLIF: 2.67 ± 4.10, P = 0.18), ODI (MIS-TLIF: 11.61 ± 25.52 vs. open-TLIF: 14.88 ± 22.07, P = 0.47), and SF-36 physical component score (MIS-TLIF: 8.61 ± 17.72 vs. open-TLIF: 7.61 ± 15.55, P = 0.93), and SF-36 mental component score (MIS-TLIF: 4.35 ± 22.71 vs. open-TLIF: 5.96 ± 21.09, P = 0.69). Postoperative complications rates between both cohorts were also not significantly divergent between (12.50% vs. 11.11%, P = 0.51). MIS-TLIF is a safe and viable option for lumbar fusion in morbidly obese patients and, compared with open-TLIF, resulted in similar improvement in pain and functional disability. Postoperative complications rates between both cohorts were also not significantly divergent. Copyright © 2015 Elsevier Inc. All rights reserved.

  18. Effect of minimally invasive technique on return to work and narcotic use following transforaminal lumbar inter-body fusion: a review.

    PubMed

    Parker, Scott L; Lerner, Jason; McGirt, Matthew J

    2012-01-01

    Low back pain is one of the most prevalent and disabling musculoskeletal conditions affecting the working population in the United States. Informed, shared decision making among patients, clinicians, and case managers about treatment options for chronic low back pain-including the role of spinal fusion where medically necessary-can have a meaningful impact on return to work, normal function, and economic outcomes. Minimally invasive techniques for lumbar spinal fusion, including transforaminal lumbar interbody fusion (MIS TLIF) have recently been introduced with the goal of smaller operative wounds, less tissue trauma, and faster postoperative recovery when compared with open fusion. Although similar long-term clinical outcomes have been reported for MIS TLIF and open TLIF, the relative merits with respect to workplace productivity have not been comprehensively investigated. Time to return to work and narcotic independence after MIS TLIF and open TLIF are important parameters that may affect overall workplace productivity, and as such are the focus of this study. This study was performed via a review of the literature. We performed a systematic literature review to identify all published articles that reported on the postoperative outcomes of patients, as assessed by return to work or narcotic independence status or both, following MIS TLIF or open TLIF. A cumulative comparison was made for all included MIS TLIF versus open TLIF surgeries. Seventy-four published studies reported postoperative outcomes following MIS TLIF or open TLIF; only five (6.8%) studies directly described time to return to work or duration of narcotic use postoperatively or both, and were therefore included into the analysis of this review. Four studies in the published literature describe time to return to work following MIS TLIF or open TLIF, and two studies describe time to narcotic independence. Overall, the reviewed literature suggests that MIS TLIF may be associated with an accelerated time to narcotic independence and return to work versus open TLIF. There are limited data regarding time to return to work and duration of postoperative narcotic use following TLIF for low back pain. The available data appear to suggest that MIS TLIF may be associated with accelerated return to work and narcotic independence compared with open TLIF. Further analysis will be necessary to quantify the impact of MIS TLIF on workplace productivity and the indirect costs borne by patients and employers. Such information will be of value to case managers, disability managers, employers, patients, and clinicians aligned on reducing morbidity and hastening return to normal function.

  19. Electrochemical doping for lowering contact barriers in organic field effect transistors

    PubMed Central

    Schaur, Stefan; Stadler, Philipp; Meana-Esteban, Beatriz; Neugebauer, Helmut; Serdar Sariciftci, N.

    2012-01-01

    By electrochemically p-doping pentacene in the vicinity of the source-drain electrodes in organic field effect transistors the injection barrier for holes is decreased. The focus of this work is put on the influence of the p-doping process on the transistor performance. Cyclic voltammetry performed on a pentacene based transistor exhibits a reversible p-doping response. This doped state is evoked at the transistor injection electrodes. An improvement is observed when comparing transistor characteristics before and after the doping process apparent by an improved transistor on-current. This effect is reflected in the analysis of the contact resistances of the devices. PMID:23483101

  20. VOLTAGE-CONTROLLED TRANSISTOR OSCILLATOR

    DOEpatents

    Scheele, P.F.

    1958-09-16

    This patent relates to transistor oscillators and in particular to those transistor oscillators whose frequencies vary according to controlling voltages. A principal feature of the disclosed transistor oscillator circuit resides in the temperature compensation of the frequency modulating stage by the use of a resistorthermistor network. The resistor-thermistor network components are selected to have the network resistance, which is in series with the modulator transistor emitter circuit, vary with temperature to compensate for variation in the parameters of the transistor due to temperature change.

  1. Evolutionary Technique for Automated Synthesis of Electronic Circuits

    NASA Technical Reports Server (NTRS)

    Stoica, Adrian (Inventor); Salazar-Lazaro, Carlos Harold (Inventor)

    2007-01-01

    An evolvable circuit includes a plurality of reconfigurable switches, a plurality of transistors within a region of the circuit, the plurality of transistors having terminals, the plurality of transistors being coupled between a power source terminal and a power sink terminal so as to be capable of admitting power between the power source terminal and the power sink terminal, the plurality of transistors being coupled so that every transistor to transistor terminal coupling within the region of the circuit comprises a reconfigurable switch.

  2. Assessment of the Potential for Color Overlays to Enhance the Reading Skills of Enlisted Navy Recruits

    DTIC Science & Technology

    2006-07-30

    as an intervention . Readers with MIS symptoms read significantly faster with their chosen overlay than without it. These findings justify further...recent years, the techniques for routine diagnosis and effective intervention methods for MIS have been improved and developed. Although Irlen is...The British Royal Navy, for example, screens for MIS on a case-by-case basis and provides overlays and filters as intervention . Furthermore

  3. Thomas checks the condition of the MIS-B middeck locker experiment

    NASA Image and Video Library

    1995-07-28

    STS070-329-022 (13-22 JULY 1995)--- Astronaut Donald A. Thomas, mission specialist, prepares to activate the Microcapsules in Space (MIS-B) experiment on the space shuttle Discovery?s middeck. MIS-B is an Army project to improve the understanding of microencapsulated drug technology and demonstrate the feasibility of producing pharmaceutical microcapsules in the weightlessness of space. This is the second flight of the experiment, which originally flew on STS-53 in 1992. Microcapsules are tiny spheres about 50 to 100 micrometers in diameter (about the thickness of a strand of human hair). They are used to develop high-performance chemical products and innovative pharmaceuticals such as time-release prescriptions. The drug used in the MIS experiments was ampicillin.

  4. Doped organic transistors operating in the inversion and depletion regime

    PubMed Central

    Lüssem, Björn; Tietze, Max L.; Kleemann, Hans; Hoßbach, Christoph; Bartha, Johann W.; Zakhidov, Alexander; Leo, Karl

    2013-01-01

    The inversion field-effect transistor is the basic device of modern microelectronics and is nowadays used more than a billion times on every state-of-the-art computer chip. In the future, this rigid technology will be complemented by flexible electronics produced at extremely low cost. Organic field-effect transistors have the potential to be the basic device for flexible electronics, but still need much improvement. In particular, despite more than 20 years of research, organic inversion mode transistors have not been reported so far. Here we discuss the first realization of organic inversion transistors and the optimization of organic depletion transistors by our organic doping technology. We show that the transistor parameters—in particular, the threshold voltage and the ON/OFF ratio—can be controlled by the doping concentration and the thickness of the transistor channel. Injection of minority carriers into the doped transistor channel is achieved by doped contacts, which allows forming an inversion layer. PMID:24225722

  5. Deep-sea benthic response to rapid climatic oscillations of the last glacial cycle in the SE Bay of Biscay

    NASA Astrophysics Data System (ADS)

    Rodriguez-Lazaro, J.; Pascual, A.; Cacho, I.; Varela, Z.; Pena, L. D.

    2017-12-01

    Paleoclimatic evolution of the last 140 ka (Marine Isotopic Stages MIS 1 to MIS 5) in the South Bay of Biscay has been studied by considering microfossil changes in sediment samples of deep core PP10-17. This core was retrieved at 2882 m water depth (mwd) in the Landas Plateau and is formed by 1792 cm of clay-silt continuously deposited sediment. For this study, a total of 114 samples have been examined, yielding approximately 60 thousands of specimens of foraminifers (181 benthic species, BF) and ostracods (70 spp.). Reconstruction of the benthic response is based on the main foraminifer and ostracod species by considering their oxic/anoxic character as well as other ecological features of the assemblages. Detailed quantification of microfossils (planktonic and benthic foraminifers, ostracods) together with grain size analyses and magnetic susceptibility of the sediments allow us to characterize many of the climatic events registered in this core. Based on a robust chronostratigraphy by correlation with reference core MD95-2002 and Greenland ice core records (GICC05modelext), we are able to characterize a detailed response of benthic environments to cooling/warming, oxygen-content and productivity cycles in the region. MIS 5 has been characterized by oscillations of the planktonic/benthic foraminifer ratio (Oceanity index, OI; 60-90%); this index was higher (90-100%) and stable through the MIS 4-MIS 3 intervals. We found BF species indicators of different climatic-related events. Thus, MIS 5a, c, e interstadials are evidenced by Bulimina gibba and B. aculeata while the stadials MIS 5b, d are shown by the occurrence of Melonis pompilioides. Heinrich events, with massive iceberg discharges into the N Atlantic Ocean, are indicated by presence of Globobulimina affinis, particularly during the MIS 4 to MIS 2 interval. The beginning of MIS 4 is indicated by the appearance of new species of BF and an increase of Cassidulina laevigata. Krithe spp. and C. laevigata are good indicators of the LGM (Last Glacial Maximum, 19-23 ka) when the OI decreased. Other cooling periods (e.g. Younger Dryas, YD, around 12-13 ka) are shown as well by an increase of M. pompilioides, similar to that of the MIS 5d stadial. The Holocene (11.5 ka to present) is marked by an increase in the oceanity index, disappearance of cold-water indicators and the occurrence of Uvigerina peregrina. A shallow infaunal microhabitat of benthics foraminifers (Cibicides, Cassidulina, Uvigerina) and ostracods (Krithe, Argilloecia) has been linked to favorable bottom conditions, with oxic to slightly suboxic conditions (high diversity and equitability of assemblages) reflecting an active Atlantic Meridional Overturning Circulation (AMOC) during many D/O interstadials. The opposite conditions were established for deep infaunal BF (Bulimina, Globobulimina) where the strong dysoxic bottom conditions are indicative of poor ventilation produced by a reduction or shutdown of the AMOC during Heinrich stadials.

  6. Minimally invasive versus open fusion for Grade I degenerative lumbar spondylolisthesis: analysis of the Quality Outcomes Database.

    PubMed

    Mummaneni, Praveen V; Bisson, Erica F; Kerezoudis, Panagiotis; Glassman, Steven; Foley, Kevin; Slotkin, Jonathan R; Potts, Eric; Shaffrey, Mark; Shaffrey, Christopher I; Coric, Domagoj; Knightly, John; Park, Paul; Fu, Kai-Ming; Devin, Clinton J; Chotai, Silky; Chan, Andrew K; Virk, Michael; Asher, Anthony L; Bydon, Mohamad

    2017-08-01

    OBJECTIVE Lumbar spondylolisthesis is a degenerative condition that can be surgically treated with either open or minimally invasive decompression and instrumented fusion. Minimally invasive surgery (MIS) approaches may shorten recovery, reduce blood loss, and minimize soft-tissue damage with resultant reduced postoperative pain and disability. METHODS The authors queried the national, multicenter Quality Outcomes Database (QOD) registry for patients undergoing posterior lumbar fusion between July 2014 and December 2015 for Grade I degenerative spondylolisthesis. The authors recorded baseline and 12-month patient-reported outcomes (PROs), including Oswestry Disability Index (ODI), EQ-5D, numeric rating scale (NRS)-back pain (NRS-BP), NRS-leg pain (NRS-LP), and satisfaction (North American Spine Society satisfaction questionnaire). Multivariable regression models were fitted for hospital length of stay (LOS), 12-month PROs, and 90-day return to work, after adjusting for an array of preoperative and surgical variables. RESULTS A total of 345 patients (open surgery, n = 254; MIS, n = 91) from 11 participating sites were identified in the QOD. The follow-up rate at 12 months was 84% (83.5% [open surgery]; 85% [MIS]). Overall, baseline patient demographics, comorbidities, and clinical characteristics were similarly distributed between the cohorts. Two hundred fifty seven patients underwent 1-level fusion (open surgery, n = 181; MIS, n = 76), and 88 patients underwent 2-level fusion (open surgery, n = 73; MIS, n = 15). Patients in both groups reported significant improvement in all primary outcomes (all p < 0.001). MIS was associated with a significantly lower mean intraoperative estimated blood loss and slightly longer operative times in both 1- and 2-level fusion subgroups. Although the LOS was shorter for MIS 1-level cases, this was not significantly different. No difference was detected with regard to the 12-month PROs between the 1-level MIS versus the 1-level open surgical groups. However, change in functional outcome scores for patients undergoing 2-level fusion was notably larger in the MIS cohort for ODI (-27 vs -16, p = 0.1), EQ-5D (0.27 vs 0.15, p = 0.08), and NRS-BP (-3.5 vs -2.7, p = 0.41); statistical significance was shown only for changes in NRS-LP scores (-4.9 vs -2.8, p = 0.02). On risk-adjusted analysis for 1-level fusion, open versus minimally invasive approach was not significant for 12-month PROs, LOS, and 90-day return to work. CONCLUSIONS Significant improvement was found in terms of all functional outcomes in patients undergoing open or MIS fusion for lumbar spondylolisthesis. No difference was detected between the 2 techniques for 1-level fusion in terms of patient-reported outcomes, LOS, and 90-day return to work. However, patients undergoing 2-level MIS fusion reported significantly better improvement in NRS-LP at 12 months than patients undergoing 2-level open surgery. Longer follow-up is needed to provide further insight into the comparative effectiveness of the 2 procedures.

  7. Comparison of esophagectomy with and without thoracotomy in a low-resource tertiary care center in a developing country.

    PubMed

    Kothari, K C; Nair, C Krishnan; George, P S; Patel, M H; Gatti, R C; Gurjar, G C

    2011-11-01

    Esophageal cancer surgery is traditionally performed by a number of open surgical approaches. Open approaches require thoracotomy and laparotomy. Developments in instrumentation and optics have allowed the use of minimally invasive approaches to esophageal cancer, which had been traditionally managed by open operation. Minimally invasive surgery (MIS) avoids thoracotomy and laparotomy and results in quicker return to normal functions and less morbidity. In this prospective study, we compared the immediate surgical and oncologic outcomes of patients who have undergone MIS with those who have had open surgery. From November 1, 2003 to March 30, 2006, 62 cases of carcinoma esophagus were operated in Surgical unit 3 (MIS unit) in the institute. Out of the 62 patients, 34 (54.8%) underwent minimally invasive esophagectomy (MIE), and the remaining 28 patients (45.2%) underwent open surgery. Both operations were done by the same team of surgeons. The groups were compared in terms of perioperative outcomes, morbidity, mortality, and adequacy of oncologic excision. The average duration for MIS was 312.35 min (60-480 min), which was more than that of open group surgery whose average duration was 261.96 min (60-360 min). This difference was found to be not significant (P < 0.110). The average blood loss was 275.74 mL (200-500 mL) in minimally invasive group compared with 312.50 (200-500 mL) in open group (P-value 0.33). Four patients (11.76%) in MIS group had been converted to open surgery. Average duration of hospitalization was 11.9 (4-24) days in MIS group compared with 12.19 (5-24) days in open group (P-value 0.282). Nine (26.47%) patients in MIS group had developed major or minor morbidity. Similarly, eight (28.57%) patients in open group had morbidity. One patient each expired in each group. The morbidity and mortality rates were not statistically significant. There were four leaks (11.76%) in MIS group and three leaks (10.71%) in open group (P-value 0.85). Regarding the extent of nodal clearance, an average number of 9.5 (0-19) nodes were removed in MIS group compared with an average of 7.26 (0-12) nodes in open group (P-value 0.05). Better visibility and magnification enabled more number of lymph nodes to be removed in MIS group. MIE is oncologically safe compared with open surgery. It has almost similar postoperative course, morbidity pattern, and duration of hospital stay as open surgery. Increased duration of procedure compared with open surgery is a disadvantage of MIS, especially in the early part of learning curve. © 2011 Copyright the Authors. Journal compilation © 2011, Wiley Periodicals, Inc. and the International Society for Diseases of the Esophagus.

  8. Methane seep events of the southern Joetsu Knoll since middle Pleistocene based on benthic foraminifera

    NASA Astrophysics Data System (ADS)

    Oi, T.; Akiba, F.; Matsumoto, R.; Kakuwa, Y.

    2016-12-01

    Gas hydrates were collected at several sites off Joetsu which presented anomalous seismic structures. "Gas chimneys", major host structures for shallow gas hydrates, were recognized ROV off Joetsu in eastern margin of the Japan Sea, as were a number of active methane seeps. The assemblage components and carbon isotope of benthic foraminifera, which are ubiquitous in global marine settings, can indicate methane seep environments (Akimoto et al., 1994; Bhaumik and Gupta, 2007). Preliminary work by Oi et al. (2015) documented the obvious occurrences of methane related foraminifera, Rutherfordoides sp., in three core sediments recovered from Umitaka Spur, west Oki Trough and north Mogami Trough in the eastern margin of the Japan Sea, and found them to comprise the early part of the MIS 2, calculated to 28-25ka. These records suggest that active methane seep events might occur at the same time during early MIS 2, but were confined within the last 100ka. In this study, we analyzed benthic foraminiferal fossils from drilling core J04RB (core length 122 m; one of the gas hydrate bearing sites at a southern part of the Joetsu Knoll) in order to document methane seep events during the last 500ka. Firstly, we estimated sedimentation ages from diatom biostratigraphy and identification of Aso-1 tephra. Based on diatom components, we recognized a boundary between NPD (Neogene North Pacific diatom Zonations) 12 and NPD11, estimated at 300 ka (MIS8/9; Yanagisawa and Akiba, 1998). The bottom age was estimated to almost 530-560 ka (around MIS14) especially from the alternation with warm and cold diatom zones (Akiba et al., 2014). Secondary, we could suppose the paleoenvironments from benthic foraminifera as below. 1. The rare benthic foraminifera during the cold stages (MIS8, MIS10, and MIS12) indicate anoxic bottom conditions characteristic of falling sea level, just as with MIS 2. 2. We recognized the continuous distributions of tiny methane related specimens of Rutherfordoides sp. during MIS10. In order to confirm new records of active methane seep events in the Joetsu Knoll, we need to measure isotope records of this species. This study was conducted under the commission from AIST as a part of the methane hydrate research project of METI (the Ministry of Economy, Trade and Industry, Japan).

  9. A Tianshan Mountains loess-paleosol sequence indicates anti-phase climatic variations in arid central Asia and in East Asia

    NASA Astrophysics Data System (ADS)

    Li, Guoqiang; Chen, Fahu; Xia, Dunsheng; Yang, He; Zhang, Xiaojian; Madsen, David; Oldknow, Chris; Wei, Haitao; Rao, Zhiguo; Qiang, Mingrui

    2018-07-01

    Paleoclimatic changes in arid central Asia (ACA), one of the largest arid regions in the world, are complex and the nature of these changes on orbital cycles remains unclear. Widely distributed loess records in ACA potentially provide records of paleoclimatic variation, but these records are difficult to interpret due to a lack of robust high resolution chronologies. K-feldspar pIRIR dating was employed to date 37 samples from a 13 m loess-paleosol sequence (section KS15) in an intermontane basin of the Tianshan Mountains, central ACA, NW China. The reliability of the pIRIR ages was determined by using internal checks of luminescence characteristics of the pIR50IR290 and pIR200IR290 signals, and by comparing pIR50IR290 and pIR200IR290 ages. A high resolution chronology for the loess-paleosol sequence, spanning 130-45 ka, was established using Bacon age/depth modeling. In combination with climate proxy indexes of magnetic susceptibility, total organic material, and δ13C of organic remains from the sequence, our results suggest: (1) the pIRIR ages utilizing pIR50IR290 and pIR200IR290 signals are consistent for loess samples <150 ka; (2) eolian loess was deposited in intermontane basins of the Tianshan Mountains by at least ∼150 ka, with a steadily increasing rate of loess deposition from the last interglacial to the last glacial period; (3) ACA had a moist climate, characterized by paleosol development, during periods at 117-109, 97-85, 77-70 and 58-50 ka, corresponding to MIS 5d, MIS 5b, MIS 5-4 and MIS 3c; (4) ACA had dry climates, characterized by loess deposition, at 131-117, 109-97, 85-76, 70-58 and 50-46 ka, corresponding to MIS 5e, MIS 5c, MIS a and MIS 3b; and (5) during sub-stages of MIS 5 the ACA climate was characterized by cold-moist to warm-dry shifts which appear to be related to ∼21 ka precession cycles, but inversely related to Northern Hemisphere summer insolation patterns. Moisture variation in ACA thus has an anti-phase relationship to that in monsoonal East Asia. Orbital forcing may be responsible for this moisture variation in ACA.

  10. How are patients influenced when counseled for minimally invasive lumbar spine surgeries? A stepwise model assessing pivotal information for decision-making.

    PubMed

    Hey, Hwee Weng Dennis; Kumar, Nishant; Teo, Alex Quok An; Tan, Kimberly-Anne; Kumar, Naresh; Liu, Ka-Po Gabriel; Wong, Hee-Kit

    2017-08-01

    Although minimally invasive surgery (MIS)-transforaminal lumbar interbody fusion (TLIF) has many evidence-based short-term benefits over open TLIF, both procedures have similar long-term outcomes. Patients' preference for MIS over open TLIF may be confounded by a lack of understanding of what each approach entails. The study aimed to identify the various factors influencing patients' choice between MIS and open TLIF. This is a cross-sectional study conducted at a tertiary health-care institution. Patients, for whom TLIF procedures were indicated, were recruited over a 3-month period from specialist outpatient clinics. The outcome measure was patients' choice of surgical approach (MIS or open). All patients were subjected to a stepwise interviewing process and were asked to select between open and MIS approaches at each step. Further subgroup analysis stratifying subjects based on stages of decision-making was performed to identify key predictors of selection changes. No sources of funding were required for this study and there are no conflicts of interests. Fifty-four patients with a mean age of 55.8 years participated in the study. Thirteen (24.1%) consistently selected a single approach, whereas 31 (57.4%) changed their selection more than once during the interviewing process. Overall, 12 patients (22.2%) had a final decision different from their initial choice, and 15 patients (27.8%) were unable to decide. A large proportion of patients (65.0%) initially favored the open approach's midline incision. This proportion dropped to 16.7% (p<.001) upon mention of the term MIS. The proportion of patients favoring MIS dropped significantly following discussion on the pros and cons (p=.002) of each approach, as well as conversion or revision surgery (p=.017). Radiation and cosmesis were identified as the two most important factors influencing patients' final decisions. The longer midline incision of the open approach is cosmetically more appealing to patients than the paramedian stab wounds of MIS. The advantages of the MIS approach may not be as valued by patients as they are by surgeons. Given the equivalent long-term outcomes of both approaches, it is crucial that patients are adequately informed during preoperative counseling to achieve the best consensus decision. Copyright © 2017 Elsevier Inc. All rights reserved.

  11. Interband Lateral Resonant Tunneling Transistor.

    DTIC Science & Technology

    1994-11-14

    INTERBAND LATERAL RESONANT TUNNELING TRANSISTOR 10 BACKGROUND OF THE INVENTION Field of the Invention This invention pertains to a tunneling transistor...and in 15 particular to an interband lateral resonant tunneling transistor. Description of Related Art Conventional semiconductor technologies are... interband lateral resonant tunneling transistor along the cross-section B-B of Figure 2c. Figure 4 is another preferred embodiment cross-sectional 20

  12. Interglacial/glacial changes in coccolith-rich deposition in the SW Pacific Ocean: An analogue for a warmer world?

    NASA Astrophysics Data System (ADS)

    Duncan, Bella; Carter, Lionel; Dunbar, Gavin; Bostock, Helen; Neil, Helen; Scott, George; Hayward, Bruce W.; Sabaa, Ashwaq

    2016-09-01

    Satellite observations of middle to high latitudes show that modern ocean warming is accompanied by increased frequency and poleward expansion of coccolithophore blooms. However, the outcomes of such events and their causal processes are unclear. In this study, marine sediment cores are used to investigate past coccolithophore production north and south of the Subtropical Front. Calcareous pelagites from subtropical waters off northernmost New Zealand (site P71) and from subantarctic waters on Campbell Plateau (Ocean Drilling Program [ODP] site 1120C) record marked changes in pelagite deposition. At both locations, foraminiferal-rich sediments dominate glacial periods whereas coccolith-rich sediments characterise specific interglacial periods. Sediment grain size has been used to determine relative abundances of coccoliths and foraminifers. Results show coccoliths prevailed around certain Marine Isotope Stage (MIS) transitions, at MIS 7b/a and MIS 2/1 at P71, and at MIS 6/5e at ODP 1120C. Palaeo-environmental proxies suggest that coccolithophore production and deposition at P71 reflect enhanced nutrient availability associated with intense winter mixing in the subtropical Tasman Sea. An increased inflow of that warm, micronutrient-bearing subtropical water in concert with upper ocean thermal stratification in late spring/summer, led to peak phytoplankton production. At ODP 1120C during MIS 6/5e, an increased inflow of subtropical water, warm sea surface temperatures and a thermally stratified upper ocean also favoured coccolithophore production. These palaeo-environmental reconstructions together with model simulations suggest that (i) future subtropical coccolithophore production at P71 is unlikely to reach abundances recorded during MIS 7b/a but (ii) future subantarctic production is likely to dominate sedimentation over Campbell Plateau as modern conditions trend towards those prevalent during MIS 5e.

  13. Uranium uptake history, open-system behaviour and uranium-series ages of fossil Tridacna gigas from Huon Peninsula, Papua New Guinea

    NASA Astrophysics Data System (ADS)

    Ayling, Bridget F.; Eggins, Stephen; McCulloch, Malcolm T.; Chappell, John; Grün, Rainer; Mortimer, Graham

    2017-09-01

    Molluscs incorporate negligible uranium into their skeleton while they are living, with any uranium uptake occurring post-mortem. As such, closed-system U-series dating of molluscs is unlikely to provide reliable age constraints for marine deposits. Even the application of open-system U-series modelling is challenging, because uranium uptake and loss histories can affect time-integrated uranium distributions and are difficult to constrain. We investigate the chemical and isotopic distribution of uranium in fossil Tridacna gigas (giant clams) from Marine Isotope Stage (MIS) 5e (128-116 ka) and MIS 11 (424-374 ka) reefs at Huon Peninsula in Papua New Guinea. The large size of the clams enables detailed chemical and isotopic mapping of uranium using LA-ICPMS and LA-MC-ICPMS techniques. Within each fossil Tridacna specimen, marked differences in uranium concentrations are observed across the three Tridacna growth zones (outer, inner, hinge), with the outer and hinge zones being relatively enriched. In MIS 5e and MIS 11 Tridacna, the outer and hinge zones contain approximately 1 ppm and 5 ppm uranium respectively. In addition to uptake of uranium, loss of uranium appears prevalent, especially in the MIS 11 specimens. The effect of uranium loss is to elevate measured [230Th/238U] values with little effect on [234U/238U] values. Closed-system age estimates are on average 50% too young for the MIS 5e Tridacna, and 25% too young for the MIS 11 Tridacna. A complex, multi-stage uptake and loss history is interpreted for the fossil Tridacna and we demonstrate that they cannot provide independent, reliable geochronological controls on the timing of past reef growth at Huon Peninsula.

  14. Late Pleistocene climate change and landscape dynamics in the Eastern Alps: the inner-alpine Unterangerberg record (Austria)

    PubMed Central

    Starnberger, Reinhard; Drescher-Schneider, Ruth; Reitner, Jürgen M.; Rodnight, Helena; Reimer, Paula J.; Spötl, Christoph

    2013-01-01

    Drill cores from the inner-alpine valley terrace of Unterangerberg, located in the Eastern Alps of Austria, offer first insights into a Pleistocene sedimentary record that was not accessible so far. The succession comprises diamict, gravel, sand, lignite and thick, fine grained sediments. Additionally, cataclastic deposits originating from two paleo-landslide events are present. Multi-proxy analyses including sedimentological and palynological investigations as well as radiocarbon and luminescence data record the onset of the last glacial period (Würmian) at Unterangerberg at ∼120–110 ka. This first time period, correlated to the MIS 5d, was characterised by strong fluvial aggradation under cold climatic conditions, with only sparse vegetation cover. Furthermore, two large and quasi-synchronous landslide events occurred during this time interval. No record of the first Early Würmian interstadial (MIS 5c) is preserved. During the second Early Würmian interstadial (MIS 5a), the local vegetation was characterised by a boreal forest dominated by Picea, with few thermophilous elements. The subsequent collapse of the vegetation is recorded by sediments dated to ∼70–60 ka (i.e. MIS 4), with very low pollen concentrations and the potential presence of permafrost. Climatic conditions improved again between ∼55 and 45 ka (MIS 3) and cold-adapted trees re-appeared during interstadials, forming an open forest vegetation. MIS 3 stadials were shorter and less severe than the MIS 4 at Unterangerberg, and vegetation during these cold phases was mainly composed of shrubs, herbs and grasses, similar to what is known from today's alpine timberline. The Unterangerberg record ended at ∼45 ka and/or was truncated by ice during the Last Glacial Maximum. PMID:23805019

  15. First clinical results of minimally invasive vector lumbar interbody fusion (MIS-VLIF) in spondylodiscitis and concomitant osteoporosis: a technical note.

    PubMed

    Rieger, Bernhard; Jiang, Hongzhen; Ruess, Daniel; Reinshagen, Clemens; Molcanyi, Marek; Zivcak, Jozef; Tong, Huaiyu; Schackert, Gabriele

    2017-12-01

    First description of MIS-VLIF, a minimally invasive lumbar stabilization, to evaluate its safety and feasibility in patients suffering from weak bony conditions (lumbar spondylodiscitis and/or osteoporosis). After informed consent, 12 patients suffering from lumbar spondylodiscitis underwent single level MIS-VLIF. Eight of them had a manifest osteoporosis, either. Pre- and postoperative clinical status was documented using numeric rating scale (NRS) for leg and back pain. In all cases, the optimal height for the cage was preoperatively determined using software-based range of motion and sagittal balance analysis. CT scans were obtained to evaluate correct placement of the construct and to verify fusion after 6 months. Since 2013, 12 patients with lumbar pyogenic spondylodiscitis underwent MIS-VLIF. Mean surgery time was 169 ± 28 min and average blood loss was less than 400 ml. Postoperative CT scans showed correct placement of the implants. Eleven patients showed considerable postoperative improvement in clinical scores. In one patient, we observed screw loosening. After documented bony fusion in the CT scan, the fixation system was removed in two cases to achieve lower material load. The load-bearing trajectories (vectors) of MIS-VLIF are different from those of conventional coaxial pedicle screw implantation. The dorsally converging construct combines the heads of the dorsoventral pedicle screws with laminar pedicle screws following cortical bone structures within a small approach. In case of lumbar spondylodiscitis and/or osteoporosis, MIS-VLIF relies on cortical bony structures for all screw vectors and the construct does not depend on conventional coaxial pedicle screws in the presence of inflamed, weak, cancellous or osteoporotic bone. MIS-VLIF allows full 360° lumbar fusion including cage implantation via a small, unilateral dorsal midline approach.

  16. Paleo-surfaces of glacio-eustatically forced aggradational successions in the coastal area of Rome: Assessing interplay between tectonics and sea-level during the last ten interglacials

    NASA Astrophysics Data System (ADS)

    Marra, Fabrizio; Florindo, Fabio; Anzidei, Marco; Sepe, Vincenzo

    2016-09-01

    Recently acquired geochronological and stratigraphic data provide new information on the sedimentary successions deposited by the Paleo-Tiber River in the coastal and near-coastal area of Rome in consequence of the glacio-eustatic changes, allowing to better define their inner geometry and palaeogeographic spatial distribution. In the present work we use this revised sedimentary dataset to provide a geochronologically constrained and tectonically adjusted record of paleo sea-level indicators. Aimed at this scope, we review literature data acquired in the last 35 years and using the new geochronological constraints we pinpoint the coastal-to-fluvial terraces of MIS 5 and MIS 7, mapping their relic surfaces in an area of 30 km along the coast north and south of the Tiber River mouth, and 20 km inland of the fluvial valleys of Tiber and Aniene rivers. The geometry of these paleo-surfaces provides constraints on the relative elevation of the sea-level during the last interglacials and on the uplift rates in this region during the last 200 ka. In particular, we recognize the previously undetected terraces of MIS 5.3 and MIS 5.1 interstadials, and we assess their spatial relationship with respect to MIS 5.5, providing important information on sea-level oscillations during this time span. Comparison with sea-level indicators provided by previous aggradational successions deposited during past interglacials spanning MIS 9 through MIS 21 in the coastal area of Rome, also allows us to reconstruct the tectonic history and investigate its relationships with the Middle-Pleistocene volcanic activity of the Roman Comagmatic Region along the Tyrrhenian Sea margin of Italy in the last 900 ka.

  17. A Prospective Randomized Peri- and Post-Operative Comparison of the Minimally Invasive Anterolateral Approach Versus the Lateral Approach

    PubMed Central

    Landgraeber, Stefan; Quitmann, Henning; Güth, Sebastian; Haversath, Marcel; Kowalczyk, Wojciech; Kecskeméthy, Andrés; Heep, Hansjörg; Jäger, Marcus

    2013-01-01

    There is still controversy as to whether minimally invasive total hip arthroplasty enhances the postoperative outcome. The aim of this study was to compare the outcome of patients who underwent total hip replacement through an anterolateral minimally invasive (MIS) or a conventional lateral approach (CON). We performed a randomized, prospective study of 75 patients with primary hip arthritis, who underwent hip replacement through the MIS (n=36) or CON (n=39) approach. The Western Ontario and McMaster Universities Osteoarthritis Index and Harris Hip score (HHS) were evaluated at frequent intervals during the early postoperative follow-up period and then after 3.5 years. Pain sensations were recorded. Serological and radiological analyses were performed. In the MIS group the patients had smaller skin incisions and there was a significantly lower rate of patients with a positive Trendelenburg sign after six weeks postoperatively. After six weeks the HHS was 6.85 points higher in the MIS group (P=0.045). But calculating the mean difference between the baseline and the six weeks HHS we evaluated no significant differences. Blood loss was greater and the duration of surgery was longer in the MIS group. The other parameters, especially after the twelfth week, did not differ significantly. Radiographs showed the inclination of the acetabular component to be significantly higher in the MIS group, but on average it was within the same permitted tolerance range as in the CON group. Both approaches are adequate for hip replacement. Given the data, there appears to be no significant long term advantage to the MIS approach, as described in this study. PMID:24191179

  18. Dead Sea drawdown and monsoonal impacts in the Levant during the last interglacial

    NASA Astrophysics Data System (ADS)

    Torfstein, Adi; Goldstein, Steven L.; Kushnir, Yochanan; Enzel, Yehouda; Haug, Gerald; Stein, Mordechai

    2015-02-01

    Sediment cores recovered by the Dead Sea Deep Drilling Project (DSDDP) from the deepest basin of the hypersaline, terminal Dead Sea (lake floor at ∼725 m below mean sea level) reveal the detailed climate history of the lake's watershed during the last interglacial period (Marine Isotope Stage 5; MIS5). The results document both a more intense aridity during MIS5 than during the Holocene, and the moderating impacts derived from the intense MIS5e African Monsoon. Early MIS5e (∼133-128 ka) was dominated by hyperarid conditions in the Eastern Mediterranean-Levant, indicated by thick halite deposition triggered by a lake-level drop. Halite deposition was interrupted however, during the MIS5e peak (∼128-122 ka) by sequences of flood deposits, which are coeval with the timing of the intense precession-forced African monsoon that generated Mediterranean sapropel S5. A subsequent weakening of this humidity source triggered extreme aridity in the Dead Sea watershed and resulting in the biggest known lake level drawdown in its history, reflected by the deposition of thick salt layers, and a capping pebble layer corresponding to a hiatus at ∼116-110 ka. The DSDDP core provides the first evidence for a direct association of the African monsoon with mid subtropical latitude climate systems effecting the Dead Sea watershed. Combined with coeval deposition of Arabia and southern Negev speleothems, Arava travertines, and calcification of Red Sea corals, the evidence points to a climatically wet corridor that could have facilitated homo sapiens migration "out of Africa" during the MIS5e peak. The hyperaridity documented during MIS5e may provide an important analogue for future warming of arid regions of the Eastern Mediterranean-Levant.

  19. MIS 5e relative sea-level changes in the Mediterranean Sea: Contribution of isostatic disequilibrium

    NASA Astrophysics Data System (ADS)

    Stocchi, Paolo; Vacchi, Matteo; Lorscheid, Thomas; de Boer, Bas; Simms, Alexander R.; van de Wal, Roderik S. W.; Vermeersen, Bert L. A.; Pappalardo, Marta; Rovere, Alessio

    2018-04-01

    Sea-level indicators dated to the Last Interglacial, or Marine Isotope Stage (MIS) 5e, have a twofold value. First, they can be used to constrain the melting of Greenland and Antarctic Ice Sheets in response to global warming scenarios. Second, they can be used to calculate the vertical crustal rates at active margins. For both applications, the contribution of glacio- and hydro-isostatic adjustment (GIA) to vertical displacement of sea-level indicators must be calculated. In this paper, we re-assess MIS 5e sea-level indicators at 11 Mediterranean sites that have been generally considered tectonically stable or affected by mild tectonics. These are found within a range of elevations of 2-10 m above modern mean sea level. Four sites are characterized by two separate sea-level stands, which suggest a two-step sea-level highstand during MIS 5e. Comparing field data with numerical modeling we show that (i) GIA is an important contributor to the spatial and temporal variability of the sea-level highstand during MIS 5e, (ii) the isostatic imbalance from the melting of the MIS 6 ice sheet can produce a >2.0 m sea-level highstand, and (iii) a two-step melting phase for the Greenland and Antarctic Ice Sheets reduces the differences between observations and predictions. Our results show that assumptions of tectonic stability on the basis of the MIS 5e records carry intrinsically large uncertainties, stemming either from uncertainties in field data and GIA models. The latter are propagated to either Holocene or Pleistocene sea-level reconstructions if tectonic rates are considered linear through time.

  20. Towards open-source, low-cost haptics for surgery simulation.

    PubMed

    Suwelack, Stefan; Sander, Christian; Schill, Julian; Serf, Manuel; Danz, Marcel; Asfour, Tamim; Burger, Wolfgang; Dillmann, Rüdiger; Speidel, Stefanie

    2014-01-01

    In minimally invasive surgery (MIS), virtual reality (VR) training systems have become a promising education tool. However, the adoption of these systems in research and clinical settings is still limited by the high costs of dedicated haptics hardware for MIS. In this paper, we present ongoing research towards an open-source, low-cost haptic interface for MIS simulation. We demonstrate the basic mechanical design of the device, the sensor setup as well as its software integration.

  1. Faithful anaphase is ensured by Mis4, a sister chromatid cohesion molecule required in S phase and not destroyed in G1 phase

    PubMed Central

    Furuya, Kanji; Takahashi, Kohta; Yanagida, Mitsuhiro

    1998-01-01

    The loss of sister chromatid cohesion triggers anaphase spindle movement. The budding yeast Mcd1/Scc1 protein, called cohesin, is required for associating chromatids, and proteins homologous to it exist in a variety of eukaryotes. Mcd1/Scc1 is removed from chromosomes in anaphase and degrades in G1. We show that the fission yeast protein, Mis4, which is required for equal sister chromatid separation in anaphase is a different chromatid cohesion molecule that behaves independent of cohesin and is conserved from yeast to human. Its inactivation in G1 results in cell lethality in S phase and subsequent premature sister chromatid separation. Inactivation in G2 leads to cell death in subsequent metaphase–anaphase progression but missegregation occurs only in the next round of mitosis. Mis4 is not essential for condensation, nor does it degrade in G1. Rather, it associates with chromosomes in a punctate fashion throughout the cell cycle. mis4 mutants are hypersensitive to hydroxyurea (HU) and UV irradiation but retain the ability to restrain cell cycle progression when damaged or sustaining a block to replication. The mis4 mutation results in synthetic lethality with a DNA ligase mutant. Mis4 may form a stable link between chromatids in S phase that is split rather than removed in anaphase. PMID:9808627

  2. Minimally invasive surgery (MIS) for total knee replacement; medium term results with minimum five year follow-up.

    PubMed

    Unwin, Olivia; Hassaballa, Mohammed; Murray, James; Harries, William; Porteous, Andrew

    2017-03-01

    MIS TKA has been shown to offer a reduced in-patient stay, but no clinical difference at two years. Whilst there may be a benefit from earlier discharge, we need to ensure that there are no detrimental effects in the medium and long-term following MIS-TKA. To report the mid-term result from a prospective randomised controlled trial (RCT) comparing MIS-TKA with standard approach for TKA. Using knee score questionnaires, we collected patient reported outcome measures (PROMs) regarding pain and function. Sixty-six patients (from an eligible cohort of 83 patients) completed the mid-term postal follow-up. There was no significant difference between groups for change in score from pre-operative to final follow-up in all three PROMs. Mean MIS and standard group improvement was: AKSS 53 and 51 (p=0.7644), OKS 15 and 16 (p=0.2341) or WOMAC 15 and 15 (p=0.9900) respectively. Both groups showed improvement in pain and function with no significant difference between groups. There was no difference between groups for revision due to malalignment at a mean six year follow-up. In addition to the early benefits regarding hospital stay and complications, we have found that at a mean of six years there was no increase in malalignment, pain or function with MIS techniques. Copyright © 2017 Elsevier B.V. All rights reserved.

  3. Evidence for millennial-scale climate change during marine isotope stages 2 and 3 at Little Lake, Western Oregon, U.S.A.

    USGS Publications Warehouse

    Grigg, L.D.; Whitlock, C.; Dean, W.E.

    2001-01-01

    Pollen and geochemical data from Little Lake, western Oregon, suggest several patterns of millennial-scale environmental change during marine isotope stage (MIS) 2 (14,100-27,600 cal yr B.P.) and the latter part of MIS 3 (27,600-42,500 cal yr B.P.). During MIS 3, a series of transitions between warm- and cold-adapted taxa indicate that temperatures oscillated by ca. 2??-4??C every 1000-3000 yr. Highs and lows in summer insolation during MIS 3 are generally associated with the warmest and coldest intervals. Warm periods at Little Lake correlate with warm sea-surface temperatures in the Santa Barbara Basin. Changes in the strength of the subtropical high and the jet stream may account for synchronous changes at the two sites. During MIS 2, shifts between mesic and xeric subalpine forests suggest changes in precipitation every 1000-3000 yr. Increases in Tsuga heterophylla pollen at 25,000 and 22,000 cal yr B.P. imply brief warmings. Minimum summer insolation and maximum global ice-volumes during MIS 2 correspond to cold and dry conditions. Fluctuations in precipitation at Little Lake do not correlate with changes in the Santa Barbara Basin and may be explained by variations in the strength of the glacial anticyclone and the position of the jet stream. ?? 2001 University of Washington.

  4. About the age and habitat of the Kirgilyakh mammoth (Dima), Western Beringia

    NASA Astrophysics Data System (ADS)

    Lozhkin, A. V.; Anderson, P. M.

    2016-08-01

    The unearthing in 1977 of a complete frozen carcass of a young mammoth, known as the Kirgilyakh mammoth or Dima: 1) provided the first opportunity for detailed study of the anatomy of a mammoth calf; 2) provided a more detailed understanding of interstadial landscapes; and 3) suggested paleoclimatic variability occurred in Western Beringia during marine isotope stage (MIS) 3. Limited access to early Russian literature resulted in unfortunate misinformation in English-language publications. Since then, six other juvenile carcasses have been discovered in northern Siberia and additional Late Pleistocene paleobotanical records have increased understanding of MIS2 and MIS3 environments. Given the new data, it seems timely to re-examine information about the Kirgilyakh mammoth in the context of: 1) correcting mistakes about the age and environments of the site, including the manner of the mammoth's death; 2) comparing paleoenvironmental settings with that of other young mammoth carcasses; and 3) revisiting the concept of mammoth-steppe. This re-examination, which places the Kirgilyakh results in a broader spatial-temporal setting, reinforces the idea that climatic variability, including the Kirgilyakh cool interval, characterized MIS3. Unstable landscapes in mountains and lowlands were key factors in deaths of the Siberian mammoth calves. The prevalence of tundra in MIS2 model reconstructions and abundance of paleobotanical data indicating mesic tundra and forest during MIS3 suggest that classification of these intervals as mammoth-steppe is problematic.

  5. Reconfigurable Complementary Logic Circuits with Ambipolar Organic Transistors

    PubMed Central

    Yoo, Hocheon; Ghittorelli, Matteo; Smits, Edsger C. P.; Gelinck, Gerwin H.; Lee, Han-Koo; Torricelli, Fabrizio; Kim, Jae-Joon

    2016-01-01

    Ambipolar organic electronics offer great potential for simple and low-cost fabrication of complementary logic circuits on large-area and mechanically flexible substrates. Ambipolar transistors are ideal candidates for the simple and low-cost development of complementary logic circuits since they can operate as n-type and p-type transistors. Nevertheless, the experimental demonstration of ambipolar organic complementary circuits is limited to inverters. The control of the transistor polarity is crucial for proper circuit operation. Novel gating techniques enable to control the transistor polarity but result in dramatically reduced performances. Here we show high-performance non-planar ambipolar organic transistors with electrical control of the polarity and orders of magnitude higher performances with respect to state-of-art split-gate ambipolar transistors. Electrically reconfigurable complementary logic gates based on ambipolar organic transistors are experimentally demonstrated, thus opening up new opportunities for ambipolar organic complementary electronics. PMID:27762321

  6. Highly Crumpled All-Carbon Transistors for Brain Activity Recording.

    PubMed

    Yang, Long; Zhao, Yan; Xu, Wenjing; Shi, Enzheng; Wei, Wenjing; Li, Xinming; Cao, Anyuan; Cao, Yanping; Fang, Ying

    2017-01-11

    Neural probes based on graphene field-effect transistors have been demonstrated. Yet, the minimum detectable signal of graphene transistor-based probes is inversely proportional to the square root of the active graphene area. This fundamentally limits the scaling of graphene transistor-based neural probes for improved spatial resolution in brain activity recording. Here, we address this challenge using highly crumpled all-carbon transistors formed by compressing down to 16% of its initial area. All-carbon transistors, chemically synthesized by seamless integration of graphene channels and hybrid graphene/carbon nanotube electrodes, maintained structural integrity and stable electronic properties under large mechanical deformation, whereas stress-induced cracking and junction failure occurred in conventional graphene/metal transistors. Flexible, highly crumpled all-carbon transistors were further verified for in vivo recording of brain activity in rats. These results highlight the importance of advanced material and device design concepts to make improvements in neuroelectronics.

  7. Reconfigurable Complementary Logic Circuits with Ambipolar Organic Transistors.

    PubMed

    Yoo, Hocheon; Ghittorelli, Matteo; Smits, Edsger C P; Gelinck, Gerwin H; Lee, Han-Koo; Torricelli, Fabrizio; Kim, Jae-Joon

    2016-10-20

    Ambipolar organic electronics offer great potential for simple and low-cost fabrication of complementary logic circuits on large-area and mechanically flexible substrates. Ambipolar transistors are ideal candidates for the simple and low-cost development of complementary logic circuits since they can operate as n-type and p-type transistors. Nevertheless, the experimental demonstration of ambipolar organic complementary circuits is limited to inverters. The control of the transistor polarity is crucial for proper circuit operation. Novel gating techniques enable to control the transistor polarity but result in dramatically reduced performances. Here we show high-performance non-planar ambipolar organic transistors with electrical control of the polarity and orders of magnitude higher performances with respect to state-of-art split-gate ambipolar transistors. Electrically reconfigurable complementary logic gates based on ambipolar organic transistors are experimentally demonstrated, thus opening up new opportunities for ambipolar organic complementary electronics.

  8. Doped Organic Transistors.

    PubMed

    Lüssem, Björn; Keum, Chang-Min; Kasemann, Daniel; Naab, Ben; Bao, Zhenan; Leo, Karl

    2016-11-23

    Organic field-effect transistors hold the promise of enabling low-cost and flexible electronics. Following its success in organic optoelectronics, the organic doping technology is also used increasingly in organic field-effect transistors. Doping not only increases device performance, but it also provides a way to fine-control the transistor behavior, to develop new transistor concepts, and even improve the stability of organic transistors. This Review summarizes the latest progress made in the understanding of the doping technology and its application to organic transistors. It presents the most successful doping models and an overview of the wide variety of materials used as dopants. Further, the influence of doping on charge transport in the most relevant polycrystalline organic semiconductors is reviewed, and a concise overview on the influence of doping on transistor behavior and performance is given. In particular, recent progress in the understanding of contact doping and channel doping is summarized.

  9. The reliability of four widely used patellar height ratios.

    PubMed

    van Duijvenbode, Dennis; Stavenuiter, Michel; Burger, Bart; van Dijke, Cees; Spermon, Jacco; Hoozemans, Marco

    2016-03-01

    The objective of this study was to evaluate the inter-observer reliability and the intra-observer reliability of four patellar height ratios: Insall-Salvati (IS), modified Insall-Salvati (MIS), Blackburne-Peel (BP) and Caton-Deschamps (CD). The patellar height ratios were assessed by four independent examiners using weight-bearing lateral knee radiographs in 30° flexion. Intra-class correlation coefficients and Fleiss' kappa's were determined. The inter-observer reliability was excellent for the IS and moderate for the other ratios. When the ratio values were categorized, the inter-observer reliability was strong for the IS, moderate for the MIS and BP, and poor for the CD. The intra-observer reliability was excellent for the IS, MIS and CD, and strong for the BP. When the ratio values were categorized, the intra-observer reliability was strong for the IS and MIS, and moderate for the other ratios. Although the IS showed best reliability, we advise to use the MIS as it showed the second best reliability but is, according to the literature, associated with better validity.

  10. MIS-11 duration key to disappearance of the Greenland ice sheet

    PubMed Central

    Robinson, Alexander; Alvarez-Solas, Jorge; Calov, Reinhard; Ganopolski, Andrey; Montoya, Marisa

    2017-01-01

    Palaeo data suggest that Greenland must have been largely ice free during Marine Isotope Stage 11 (MIS-11). However, regional summer insolation anomalies were modest during this time compared to MIS-5e, when the Greenland ice sheet likely lost less volume. Thus it remains unclear how such conditions led to an almost complete disappearance of the ice sheet. Here we use transient climate–ice sheet simulations to simultaneously constrain estimates of regional temperature anomalies and Greenland’s contribution to the MIS-11 sea-level highstand. We find that Greenland contributed 6.1 m (3.9–7.0 m, 95% credible interval) to sea level, ∼7 kyr after the peak in regional summer temperature anomalies of 2.8 °C (2.1–3.4 °C). The moderate warming produced a mean rate of mass loss in sea-level equivalent of only around 0.4 m per kyr, which means the long duration of MIS-11 interglacial conditions around Greenland was a necessary condition for the ice sheet to disappear almost completely. PMID:28681860

  11. MIS-11 duration key to disappearance of the Greenland ice sheet.

    PubMed

    Robinson, Alexander; Alvarez-Solas, Jorge; Calov, Reinhard; Ganopolski, Andrey; Montoya, Marisa

    2017-07-06

    Palaeo data suggest that Greenland must have been largely ice free during Marine Isotope Stage 11 (MIS-11). However, regional summer insolation anomalies were modest during this time compared to MIS-5e, when the Greenland ice sheet likely lost less volume. Thus it remains unclear how such conditions led to an almost complete disappearance of the ice sheet. Here we use transient climate-ice sheet simulations to simultaneously constrain estimates of regional temperature anomalies and Greenland's contribution to the MIS-11 sea-level highstand. We find that Greenland contributed 6.1 m (3.9-7.0 m, 95% credible interval) to sea level, ∼7 kyr after the peak in regional summer temperature anomalies of 2.8 °C (2.1-3.4 °C). The moderate warming produced a mean rate of mass loss in sea-level equivalent of only around 0.4 m per kyr, which means the long duration of MIS-11 interglacial conditions around Greenland was a necessary condition for the ice sheet to disappear almost completely.

  12. Preliminary Ar-40/Ar-39 age spectrum and laser probe dating of the M1 core of the Manson Impact Structure, Iowa: A K-T boundary crater candidate

    NASA Technical Reports Server (NTRS)

    Kunk, M. J.; Snee, L. W.; French, B. M.; Harlan, S. S.; Mcgee, J. J.

    1993-01-01

    Preliminary Ar-40/Ar-39 age spectrum and laser probe dating results from new drill core from the 35-km-diameter Manson Impact Structure (MIS), Iowa indicates a reasonable possibility that the MIS is a Cretaceous-Tertiary (K-T) boundary impact event. Several different types of samples from a melt-matrix breccia, a unit of apparent crater fill intersected by the M1 core, were analyzed. Ar-40/Ar-39 results from these samples indicate a maximum age for the MIS of about 65.4 plus or minus 0.4(2 sigma) Ma. Petrographic analyses of the samples indicate a high probability that all the dated samples from the melt-matrix breccia contain relict grains that were not entirely melted or degassed at the time of impact, suggesting that the actual age of the MIS could be somewhat younger than our preliminary results indicate. The results are consistent with a previously published age estimate of shocked microcline from the MIS central uplift of 65.7 plus or minus 1.0 Ma.

  13. Additive Manufacturing/Diagnostics via the High Frequency Induction Heating of Metal Powders: The Determination of the Power Transfer Factor for Fine Metallic Spheres

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Rios, Orlando; Radhakrishnan, Balasubramaniam; Caravias, George

    2015-03-11

    Grid Logic Inc. is developing a method for sintering and melting fine metallic powders for additive manufacturing using spatially-compact, high-frequency magnetic fields called Micro-Induction Sintering (MIS). One of the challenges in advancing MIS technology for additive manufacturing is in understanding the power transfer to the particles in a powder bed. This knowledge is important to achieving efficient power transfer, control, and selective particle heating during the MIS process needed for commercialization of the technology. The project s work provided a rigorous physics-based model for induction heating of fine spherical particles as a function of frequency and particle size. This simulationmore » improved upon Grid Logic s earlier models and provides guidance that will make the MIS technology more effective. The project model will be incorporated into Grid Logic s power control circuit of the MIS 3D printer product and its diagnostics technology to optimize the sintering process for part quality and energy efficiency.« less

  14. Abrupt sand-dune accumulation at the northeastern margin of the Tibetan Plateau challenges the wet MIS3a inferred from numerous lake-highstands

    PubMed Central

    Long, Hao; Fuchs, Markus; Yang, Linhai; Cheng, Hongyi

    2016-01-01

    Over the Tibetan Plateau and adjacent regions, numerous 14C-based lake records revealed a ubiquitous wet climatic period during 40–25 ka (late MIS 3), which is in contradiction with the global pattern of generally cold and dry climates. This paper focuses on OSL dating results of a large set of sand dunes and alluvial sediments (50 OSL ages) from the Qinwangchuan (QWC) Basin at the northeast edge of the Tibetan Plateau, with the aim to test the validity of the anomalous wet condition for the late MIS 3 interval, evidenced by numerous lake highstands. The abrupt sand dune accumulation as indication of increased aridity in the study area was OSL dated to ~40–13 ka. This dry climatic inference of the sand dune system from QWC apparently shows no wet MIS 3a event. Thus, the anomalous wet conditions revealed by high lake levels for the late MIS 3 phase may not be a universal phenomena across entire western China. PMID:27172907

  15. Comparison of traditional gas chromatography (GC), headspace GC, and the microbial identification library GC system for the identification of Clostridium difficile.

    PubMed Central

    Cundy, K V; Willard, K E; Valeri, L J; Shanholtzer, C J; Singh, J; Peterson, L R

    1991-01-01

    Three gas chromatography (GC) methods were compared for the identification of 52 clinical Clostridium difficile isolates, as well as 17 non-C. difficile Clostridium isolates. Headspace GC and Microbial Identification System (MIS) GC, an automated system which utilizes a software library developed at the Virginia Polytechnic Institute to identify organisms based on the fatty acids extracted from the bacterial cell wall, were compared against the reference method of traditional GC. Headspace GC and MIS were of approximately equivalent accuracy in identifying the 52 C. difficile isolates (52 of 52 versus 51 of 52, respectively). However, 7 of 52 organisms required repeated sample preparation before an identification was achieved by the MIS method. Both systems effectively differentiated C. difficile from non-C. difficile clostridia, although the MIS method correctly identified only 9 of 17. We conclude that the headspace GC system is an accurate method of C. difficile identification, which requires only one-fifth of the sample preparation time of MIS GC and one-half of the sample preparation time of traditional GC. PMID:2007632

  16. Middle Palaeolithic occupation in the Thar Desert during the Upper Pleistocene: the signature of a modern human exit out of Africa?

    NASA Astrophysics Data System (ADS)

    Blinkhorn, James; Achyuthan, Hema; Petraglia, Michael; Ditchfield, Peter

    2013-10-01

    The Thar Desert marks the transition from the Saharo-Arabian deserts to the Oriental biogeographical zone and is therefore an important location in understanding hominin occupation and dispersal during the Upper Pleistocene. Here, we report the discovery of stratified Middle Palaeolithic assemblages at Katoati in the north-eastern Thar Desert, dating to Marine Isotope Stages (MIS) 5 and the MIS 4-3 boundary, during periods of enhanced humidity. Hominins procured cobbles from gravels at the site as evidenced by early stages of stone tool reduction, with a component of more formalised point production. The MIS 5c assemblages at Katoati represent the earliest securely dated Middle Palaeolithic occupation of South Asia. Distinctive artefacts identified in both MIS 5 and MIS 4-3 boundary horizons match technological entities observed in Middle Palaeolithic assemblages in South Asia, Arabia and Middle Stone Age sites in the Sahara. The evidence from Katoati is consistent with arguments for the dispersal of Homo sapiens populations from Africa across southern Asia using Middle Palaeolithic technologies.

  17. Pre-mRNA mis-splicing of sarcomeric genes in heart failure.

    PubMed

    Zhu, Chaoqun; Chen, Zhilong; Guo, Wei

    2017-08-01

    Pre-mRNA splicing is an important biological process that allows production of multiple proteins from a single gene in the genome, and mainly contributes to protein diversity in eukaryotic organisms. Alternative splicing is commonly governed by RNA binding proteins to meet the ever-changing demands of the cell. However, the mis-splicing may lead to human diseases. In the heart of human, mis-regulation of alternative splicing has been associated with heart failure. In this short review, we focus on alternative splicing of sarcomeric genes and review mis-splicing related heart failure with relatively well studied Sarcomeric genes and splicing mechanisms with identified regulatory factors. The perspective of alternative splicing based therapeutic strategies in heart failure has also been discussed. Copyright © 2016 Elsevier B.V. All rights reserved.

  18. Fast optical detecting media based on semiconductor nanostructures for recording images obtained using charges of free photocarriers

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Kasherininov, P. G., E-mail: peter.kasherininov@mail.ioffe.ru; Tomasov, A. A.; Beregulin, E. V.

    2011-01-15

    Available published data on the properties of optical recording media based on semiconductor structures are reviewed. The principles of operation, structure, parameters, and the range of application for optical recording media based on MIS structures formed of photorefractive crystals with a thick layer of insulator and MIS structures with a liquid crystal as the insulator (the MIS LC modulators), as well as the effect of optical bistability in semiconductor structures (semiconductor MIS structures with nanodimensionally thin insulator (TI) layer, M(TI)S nanostructures). Special attention is paid to recording media based on the M(TI)S nanostructures promising for fast processing of highly informativemore » images and to fabrication of optoelectronic correlators of images for noncoherent light.« less

  19. Recent progress in photoactive organic field-effect transistors.

    PubMed

    Wakayama, Yutaka; Hayakawa, Ryoma; Seo, Hoon-Seok

    2014-04-01

    Recent progress in photoactive organic field-effect transistors (OFETs) is reviewed. Photoactive OFETs are divided into light-emitting (LE) and light-receiving (LR) OFETs. In the first part, LE-OFETs are reviewed from the viewpoint of the evolution of device structures. Device performances have improved in the last decade with the evolution of device structures from single-layer unipolar to multi-layer ambipolar transistors. In the second part, various kinds of LR-OFETs are featured. These are categorized according to their functionalities: phototransistors, non-volatile optical memories, and photochromism-based transistors. For both, various device configurations are introduced: thin-film based transistors for practical applications, single-crystalline transistors to investigate fundamental physics, nanowires, multi-layers, and vertical transistors based on new concepts.

  20. Controlled n-Type Doping of Carbon Nanotube Transistors by an Organorhodium Dimer.

    PubMed

    Geier, Michael L; Moudgil, Karttikay; Barlow, Stephen; Marder, Seth R; Hersam, Mark C

    2016-07-13

    Single-walled carbon nanotube (SWCNT) transistors are among the most developed nanoelectronic devices for high-performance computing applications. While p-type SWCNT transistors are easily achieved through adventitious adsorption of atmospheric oxygen, n-type SWCNT transistors require extrinsic doping schemes. Existing n-type doping strategies for SWCNT transistors suffer from one or more issues including environmental instability, limited carrier concentration modulation, undesirable threshold voltage control, and/or poor morphology. In particular, commonly employed benzyl viologen n-type doping layers possess large thicknesses, which preclude top-gate transistor designs that underlie high-density integrated circuit layouts. To overcome these limitations, we report here the controlled n-type doping of SWCNT thin-film transistors with a solution-processed pentamethylrhodocene dimer. The charge transport properties of organorhodium-treated SWCNT thin films show consistent n-type behavior when characterized in both Hall effect and thin-film transistor geometries. Due to the molecular-scale thickness of the organorhodium adlayer, large-area arrays of top-gated, n-type SWCNT transistors are fabricated with high yield. This work will thus facilitate ongoing efforts to realize high-density SWCNT integrated circuits.

  1. Organic transistors making use of room temperature ionic liquids as gating medium

    NASA Astrophysics Data System (ADS)

    Hoyos, Jonathan Javier Sayago

    The ability to couple ionic and electronic transport in organic transistors, based on pi conjugated organic materials for the transistor channel, can be particularly interesting to achieve low voltage transistor operation, i.e. below 1 V. The operation voltage in typical organic transistors based on conventional dielectrics (200 nm thick SiO2) is commonly higher than 10 V. Electrolyte-gated (EG) transistors, i.e. employing an electrolyte as the gating medium, permit current modulations of several orders of magnitude at relatively low gate voltages thanks to the exceptionally high capacitance at the electrolyte/transistor channel interface, in turn due to the low thickness (ca. 3 nm) of the electrical double layers forming at the electrolyte/semiconductor interface. Electrolytes based on room temperature ionic liquids (RTILs) are promising in EG transistor applications for their high electrochemical stability and good ionic conductivity. The main motivation behind this work is to achieve low voltage operation in organic transistors by making use of RTILs as gating medium. First we demonstrate the importance of the gate electrode material in the EG transistor performance. The use of high surface area carbon gate electrodes limits undesirable electrochemical processes and renders unnecessary the presence of a reference electrode to monitor the channel potential. This was demonstrated using activated carbon as gate electrode, the electronic conducting polymer MEH-PPV, poly[2-methoxy-5-(2'-ethylhexyloxy)-1,4-phenylene vinylene] channel material, and the ionic liquid [EMIM][TFSI] (1-ethyl-3-methylimidazolium bis(trifluoromethylsulfonyl)imide), as gating medium. Using high surface area gate electrodes resulted in sub-1 V operation and charge carrier mobilities of (1.0 +/- 0.5) x 10-2 cm2V -1s-1. A challenge in the field of EG transistors is to decrease their response time, a consequence of the slow ion redistribution in the transistor channel upon application of electric biases. We systematically investigated EG transistors employing RTILs belonging to the same family, i.e. based on a common anion and different cations. The transistor characteristics showed a limited cation influence in establishing the p-type doping of the conducting polymer. Interestingly, we observed that the transistor response time depends on at least two processes: the redistribution of ions from the electrolyte into the transistor channel, affecting the gate-source current (I gs); and the redistribution of charges in the transistor channel, affecting the drain-source current (Ids), as a function of time. The two processes have different rates, with the latter being the slowest. Incorporating propylene carbonate in the electrolyte proved to be an effective solution to increase the ionic conductivity, to lower the viscosity and, consequently, to reduce the transistor response time. Finally, we were able to demonstrate a multifunctional device integrating the transistor logic function with that of energy storage in a supercapacitor: the TransCap. The polymer/electrolyte/carbon vertical stacking of the EG transistor features the cell configuration of a hybrid supercapacitor. Supercapacitors are high specific power systems that, for their ability to store/deliver charge within short times may outperform batteries in applications having high power demand. When the TransCap is ON (open transistor channel), the polymer and the carbon gate electrodes store charge (Q) at a given Vgs, hence the stored energy equals Q˙V gs. When the TransCap is switched OFF, the channel and the gate are discharged and the energy can be delivered back to power other electronic components. EG transistors, making use of activated carbon as gate electrode and different RTILs as well as RTIL solvent mixtures as electrolyte gating medium, are interesting towards low voltage printable electronics. The high capacitance at the interface between the electrolyte and the transistor channel enables energy storage within the EG transistor architecture.

  2. Silicon on insulator self-aligned transistors

    DOEpatents

    McCarthy, Anthony M.

    2003-11-18

    A method for fabricating thin-film single-crystal silicon-on-insulator (SOI) self-aligned transistors. Standard processing of silicon substrates is used to fabricate the transistors. Physical spaces, between the source and gate, and the drain and gate, introduced by etching the polysilicon gate material, are used to provide connecting implants (bridges) which allow the transistor to perform normally. After completion of the silicon substrate processing, the silicon wafer is bonded to an insulator (glass) substrate, and the silicon substrate is removed leaving the transistors on the insulator (glass) substrate. Transistors fabricated by this method may be utilized, for example, in flat panel displays, etc.

  3. A multi-proxy record of MIS 11-12 deglaciation and glacial MIS 12 instability from the Sulmona basin (central Italy)

    NASA Astrophysics Data System (ADS)

    Regattieri, Eleonora; Giaccio, Biagio; Galli, Paolo; Nomade, Sebastien; Peronace, Edoardo; Messina, Paolo; Sposato, Andrea; Boschi, Chiara; Gemelli, Maurizio

    2016-01-01

    A multi-proxy record (lithology, XRF, CaCO3 content, carbonate δ18O and δ13C) was acquired from a sediment core drilled in the intermountain Sulmona basin (central Italy). Tephrostratigraphic analyses of three volcanic ash layers ascribe the investigated succession to the MIS 12-MIS 11 period, spanning the interval ca. 500-410 ka. Litho-pedo facies assemblage indicates predominant lacustrine deposition, interrupted by a minor sub-aerial and lake low stand episode. Variations in major and minor elements concentrations are related to changes in the clastic input to the lake. The oxygen isotopic composition of carbonate (δ18Oc) intervals is interpreted mainly as a proxy for the amount of precipitation in the high-altitude catchment of the karst recharge system. The record shows pronounced hydrological variability at orbital and millennial time-scales, which appears closely related to the Northern Hemisphere summer insolation pattern and replicates North Atlantic and west Mediterranean Sea Surface Temperature (SST) fluctuations. The MIS 12 glacial inception is marked by an abrupt reduction of precipitation, lowering of the lake level and enhanced catchment erosion. A well-defined and isotopically prominent interstadial with increased precipitation maybe related to insolation maxima-precession minima at ca. 465 ka. This interstadial ends abruptly at ca. 457 ka and it is followed by a phase of strong short-term instability. Drastic lake-level lowering and enhanced clastic flux characterized the MIS 12 glacial maximum. Lacustrine deposition restarted about 440 ka ago. The MIS 12-MIS 11 transition is characterized by a rapid increase in the precipitation, lake-level rise and reduction in the clastic input, interrupted by a short and abrupt return to drier conditions. Comparison with marine records from the Iberian margin and western Mediterranean suggests that major events of ice rafted debris deposition, related to southward migrations of the polar front, match the harshest periods in central Italy. This indicates strong teleconnections between Northern hemisphere ice sheet dynamics, North Atlantic oceanic conditions and Mediterranean continental hydrology.

  4. Northern Mediterranean climate since the Middle Pleistocene: a 637 ka stable isotope record from Lake Ohrid (Albania/Macedonia)

    NASA Astrophysics Data System (ADS)

    Lacey, Jack H.; Leng, Melanie J.; Francke, Alexander; Sloane, Hilary J.; Milodowski, Antoni; Vogel, Hendrik; Baumgarten, Henrike; Zanchetta, Giovanni; Wagner, Bernd

    2016-03-01

    Lake Ohrid (Macedonia/Albania) is an ancient lake with unique biodiversity and a site of global significance for investigating the influence of climate, geological, and tectonic events on the generation of endemic populations. Here, we present oxygen (δ18O) and carbon (δ13C) isotope data from carbonate over the upper 243 m of a composite core profile recovered as part of the Scientific Collaboration on Past Speciation Conditions in Lake Ohrid (SCOPSCO) project. The investigated sediment succession covers the past ca. 637 ka. Previous studies on short cores from the lake (up to 15 m, < 140 ka) have indicated the total inorganic carbon (TIC) content of sediments to be highly sensitive to climate change over the last glacial-interglacial cycle. Sediments corresponding to warmer periods contain abundant endogenic calcite; however, an overall low TIC content in glacial sediments is punctuated by discrete bands of early diagenetic authigenic siderite. Isotope measurements on endogenic calcite (δ18Oc and δ13Cc) reveal variations both between and within interglacials that suggest the lake has been subject to palaeoenvironmental change on orbital and millennial timescales. We also measured isotope ratios from authigenic siderite (δ18Os and δ13Cs) and, with the oxygen isotope composition of calcite and siderite, reconstruct δ18O of lake water (δ18Olw) over the last 637 ka. Interglacials have higher δ18Olw values when compared to glacial periods most likely due to changes in evaporation, summer temperature, the proportion of winter precipitation (snowfall), and inflow from adjacent Lake Prespa. The isotope stratigraphy suggests Lake Ohrid experienced a period of general stability from marine isotope stage (MIS) 15 to MIS 13, highlighting MIS 14 as a particularly warm glacial. Climate conditions became progressively wetter during MIS 11 and MIS 9. Interglacial periods after MIS 9 are characterised by increasingly evaporated and drier conditions through MIS 7, MIS 5, and the Holocene. Our results provide new evidence for long-term climate change in the northern Mediterranean region, which will form the basis to better understand the influence of major environmental events on biological evolution within Lake Ohrid.

  5. Sr-Nd isotopes constrain on the deposit history of the basins in the Gulf of Mexico

    NASA Astrophysics Data System (ADS)

    Li, Y.; Jiang, S.

    2015-12-01

    The Brazos-Trinity Basin IV and Ursa Basin are situated on the northern slope of the Gulf of Mexico. The Ursa basin lies in the center of late Pleistocene Mississippi River deposition, received the sediment deposition during Marine Isotope Stage (MIS) 2- 4. The Brazos-Trinity Basin IV belongs to a part of the Brazos-Trinity fan, it recorded the turbidite deposition and hemiplegic deposition during MIS1- 5. The Sr and Nd isotopic composition of the detrital composition of the sediment in both basins indicates the change of the sediment provenance during the basin-filled process. In the Ursa basin, The difference of 87Sr/86Sr ratio and ɛNd of the detrital component between MIS1,2 (87Sr/86Sr ~ 0.7219 - 0.7321, ɛNd ~ -12 - -13.4) and MIS3,4(87Sr/86Sr ~ 0.7310 - 0.7354, ɛNd ~ -16 - -17.9) is suggested to be related with the provenance change of the detrital particles since LGM. The addition of detrital particle from Appalachians with less radiogenic 87Sr/86Sr and positive ɛNd altered the character of the sediment of the Mississippi River during the last glaciation and deglaciation. In the Brazos-Trinity Basin IV, the narrow range of 87Sr/86Sr and ɛNd indicate that the sediment source of Brazos-Trinity Basin IV had not changed obviously during MIS5e to MIS2, mostly from coastal rivers such as Brazos River, Trinity River and Sabine River. The pre-fan with 87Sr/86Sr ~0.735 and ɛNd ~ -14.5 to -16.9, which is very similar to the deep sediment in the Ursa Basin with 87Sr/86Sr ~0.733 to 0.735 and ɛNd ~ -16 to -18. It is suggested that sediments of the pre-fan of the Brazos-Trinity Basin IV were supplied from the ancestral Mississippi River Delta during the low sea level (MIS 6). During the MIS5, the discharge of Mississippi River is thought switched to its present course, ~300 km to the east.

  6. Integrated geochronology of Acheulian sites from the southern Latium (central Italy): Insights on human-environment interaction and the technological innovations during the MIS 11-MIS 10 period

    NASA Astrophysics Data System (ADS)

    Pereira, Alison; Nomade, Sébastien; Moncel, Marie-Hélène; Voinchet, Pierre; Bahain, Jean-Jacques; Biddittu, Italo; Falguères, Christophe; Giaccio, Biagio; Manzi, Giorgio; Parenti, Fabio; Scardia, Giancarlo; Scao, Vincent; Sottili, Gianluca; Vietti, Amina

    2018-05-01

    We have explored the multimethod approach combining 40Ar/39Ar on single crystal, ESR on bleached quartz, and ESR/U-series on teeth to improve the age of four neighbours "Acheulian" sites of the Frosinone Province (Latium, Italy): Fontana Ranuccio, Cava Pompi (Pofi), Isoletta, and Lademagne. Ages obtained by the three methods are in mutual agreement and confirm the potential of dating with confidence Middle Pleistocene sites of Italy using these methods. At Fontana Ranuccio, the 40Ar/39Ar age (408 ± 10 ka, full external error at 2σ) obtained for the archaeological level (unit FR4) and geochemical analyses of glass shards performed on the Unit FR2a layer allow us to attribute the studied volcanic material to the Pozzolane Nere volcanic series, a well-known caldera-forming event originated from the Colli Albani volcanic district. These new data ascribe the Fontana Ranuccio site, as well as the eponym faunal unit, to the climatic optimum of Marine Isotope Stage (MIS) 11. Ages obtained for the Cava Pompi, Isoletta, and Lademagne sites cover a relatively short period of time between 408 ka and 375 ka, spanning MIS 11 climatic optimum to the MIS 11-10 transition. Analysis of small collections of lithic industries, bifacial tools, and small cores technologies from Isoletta, Lademagne, and the neighbour site of Ceprano-Campogrande shows common technical strategies for the period comprised between MIS 11 and MIS 9 (410-325 ka), such as the elaboration of flaked elephant bone industries found over the whole Latium region. However, some features found only in the Frosinone province area, like large-sized bifaces, suggest particular regional behaviours. The presence of one Levallois core in the oldest layer of Lademagne (i.e. > 405 ± 9 ka) suggests a punctual practice of this technology, also proposed as early as MIS 10/11 in the neighbour site of Guado San Nicola (Molise) in central Italy.

  7. Terrestrial biomarkers in the sediment of the East Sea (Japan Sea) since the MIS 11: implications for paleoproductivity and paleoclimatic changes

    NASA Astrophysics Data System (ADS)

    Hyun, S.; Suh, Y. J.; Woo, K. S.; Ikehara, M.

    2014-12-01

    Terrestrial biomarkers such as n-alkanes and cholesterol were analyzed to infer the variations of paleoproductivity and the corresponding paleoclimatologic information from the sediment of the Korean Plateau, East Sea (Japan Sea) since the Marine Isotope Stage (MIS) 11 (ca. 400 ka). Previous studies of SST variation have shown that glacial-interglacial scale changes were quite variable with the maximum range of 26oC in MIS 7, and the minimum range of 12oC during MIS 2 and 6. The distribution of terrestrial n-alkanes signatures is characterized by the occurrence of high odd number frequency with a minor contribution of specific compound (nC27 only). Average Chain Length (ACL) and Carbon Preferences Index (CPI), both of which are derived from n-alkane combination, show similar shifting between glacial and interglacial periods. This suggests that paleovegetation communities had been changed in responding to paleoclimatological variations, and the input amount of terrestrial compound was strongly linked with paleoclimatologic changes. In particular, depleted values of δ13Corg during MIS 2, 8 and 10 were coincident with lower nitrogen isotope values indicating local paleoceanographic effects such as paleoproductivity changes. Decoupling between δ13Corg and δ15Norg during MIS 1, 3, 5, 7 and coupling of the two during MIS 8 and 11 can be observed, which appear to be interpreted as local productivity changes. In particular, high abundance of cholesterol and C21 n-alkanes, which were derived from diatom, increased during interglacial periods. Therefore, alkenones, SST and n-alkanes signatures coincide with δ13Corg and δ15Norg variations during glacial-interglacial cycles and further strongly associated with cholesterol abundance suggesting that the paleoenvironmental conditions in East Sea during glacial-interglacial periods were sensitive not only to global climate changes but also to local paleceanographic variations. Surface water circulation around the Korea Plateau associated with eustatic sea-level changes may have been linked with paleoproductivity changes, at least on the Korea Plateau of the East Sea (Japan Sea) since the last MIS 11.

  8. Paleoproductivity vs. influx of terrestrial biomarker in sediment from the Korean Plateau, East Sea (Japan Sea) since the MIS 11

    NASA Astrophysics Data System (ADS)

    Hyun, Sangmin; Suh, Yean Jee; Ikehara, Miroru

    2015-04-01

    A piston core collected from the Korean Plateau, East Sea (Japan Sea) of Korea was conducted in terms of variations in paleoproductivity and influx of terrestrial biomarker. The distribution of terrestrial n-alkanes signatures is characterized by the occurrence of high odd number frequency with a minor contribution of specific compound (nC27 only). Average Chain Length (ACL) and Carbon Preferences Index (CPI), both of which are derived from n-alkane combination, show similar shifting between glacial and interglacial periods. Previous studies of SST variation have shown that glacial-interglacial scale changes were quite variable with the maximum range of 26oC in MIS 7, and the minimum range of 12oC during MIS 2 and 6. Therefore, paleovegetation communities had been changed in responding to paleoclimatological variations, and the input amount of terrestrial compound was strongly linked with paleoclimatologic changes. The isotopic composition of δ13C and δ15N of organic matter, which showed extreme temporal variation since MIS 11, indicates the influx of large amount of terrestrial organic matter from the neighboring terrestrial environments during MIS 2, 8 and 10. In particular, depleted values of δ13Corg during MIS 2, 8 and 10 were coincident with lower nitrogen isotope values indicating local paleoceanographic effects such as paleoproductivity changes. Decoupling between δ13Corg and δ15Norg during MIS 1, 3, 5, 7 and coupling of the two during MIS 8 and 11 can be observed, which appear to be interpreted as local productivity changes. In particular, high abundance of cholesterol and C21 n-alkanes, which were derived from diatom, increased during interglacial periods. Therefore, alkenones, SST and n-alkanes signatures coincide with δ13Corg and δ15Norg variations during glacial-interglacial cycles and further strongly associated with cholesterol abundance suggesting that the paleoenvironmental conditions in East Sea during glacial-interglacial periods were sensitive not only to global climate changes but also to local paleceanographic variations.

  9. Dynamics and timing of paleoglaciation on opposite flanks of the Ikh-Turgen Mountains, Central Asia

    NASA Astrophysics Data System (ADS)

    Blomdin, Robin; Stroeven, Arjen P.; Harbor, Jonathan M.; Gribenski, Natacha; Caffee, Marc W.; Heyman, Jakob; Rogozhina, Irina; Ivanov, Mikhail N.; Petrakov, Dmitry A.; Walther, Michael; Rudoy, Alexei N.; Zhang, Wei; Alexander, Orkhonselenge; Hättestrand, Clas; Lifton, Nathaniel A.; Jansson, Krister N.

    2017-04-01

    Spanning a northern sector of continental Central Asia, the Altai Mountains contains a rich record of glaciation. Still, there are few studies reconstructing the dynamics and timing of former glaciers in the region. We investigated the glacial history of two paleoglaciers, residing on opposite flanks of the Ikh-Turgen Mountains, straddling the border between Russia and Mongolia, using a combination of remote sensing, terrain analysis, field investigations and 10Be surface exposure dating. On the eastern side (Mongolia) of Ikh-Turgen, mean arithmetic exposure ages from a latero-frontal moraine indicate deglaciation during Marine Isotope Stage (MIS) 3 (45.3±2.7 ka, n=5) and MIS 2 (22.8±3.5 ka, n=4). These age constraints are consistent with other paleoclimate records from the region. Cold and wet conditions during early MIS 2 and MIS 3 likely triggered glacier expansions but the transition to a drier climate resulted in more restricted paleoglacier extents during MIS 2 than during MIS 3. Well-constrained MIS 3 glacier expansions in Central Asia are rare. We therefore speculate whether the climatic and topographic setting of the eastern flank of the Ikh-Turgen Mountains has allowed for a better preservation potential of these moraines, making them more suitable for surface exposure dating than other regions of Central Asia, or whether MIS 3 moraines occur more widespread but await to be robustly dated. Corresponding surface exposure ages, from the western side (Russia) of Ikh-Turgen, indicate a more complex story with large scatter ( 14-53 ka, n=8) making paleoclimate inference and comparison to other proxies difficult. Owing to their proximity, the paleoglaciers of Ikh-Turgen, should have responded similarly to climate forcing, yet they exhibited distinctly different behaviours. We discuss the connection between paleoglacier dynamics and style of moraine deposition and propose that differences in glacier dynamics caused differences in ice-marginal depositional environments, explaining the scatter in exposure ages on the western side. This study shows the importance of style of deposition in chronological studies of glacial landforms and demonstrates that certain moraine types can be difficult to use as paleoclimate proxies.

  10. Comparative Study of the Difference of Perioperative Complication and Radiologic Results: MIS-DLIF (Minimally Invasive Direct Lateral Lumbar Interbody Fusion) Versus MIS-OLIF (Minimally Invasive Oblique Lateral Lumbar Interbody Fusion).

    PubMed

    Jin, Jie; Ryu, Kyeong-Sik; Hur, Jung-Woo; Seong, Ji-Hoon; Kim, Jin-Sung; Cho, Hyun-Jin

    2018-02-01

    Retrospective observatory analysis. The purpose of this study was to compare the incidence of perioperative complication, difference of cage location, and sagittal alignment between minimally invasive oblique lateral lumbar interbody fusion (MIS-OLIF) and MIS-direct lateral lumbar interbody fusion (DLIF) in the cases of single-level surgery at L4-L5. MIS-DLIF using tubular retractor has been used for the treatment of lumbar degenerative diseases; however, blunt transpsoas dissection poses a risk of injury to the lumbar plexus. As an alternative, MIS-OLIF uses a window between the prevertebral venous structures and psoas muscle. A total of 43 consecutive patients who underwent MIS-DLIF or MIS-OLIF for various L4/L5 level pathologies between November 2011 and April 2014 by a single surgeon were retrospectively reviewed. A complication classification based on the relation to surgical procedure and effect duration was used. Perioperative complications until 3-month postoperatively were reviewed for the patients. Radiologic results including the cage location and sagittal alignment were also assessed with plain radiography. There were no significant statistical differences in perioperative parameters and early clinical outcome between 2 groups. Overall, there were 13 (59.1%) approach-related complications in the DLIF group and 3 (14.3%) in the OLIF group. In the DLIF group, 3 (45.6%) were classified as persistent, however, there was no persistent complication in the OLIF group. In the OLIF group, cage is located mostly in the middle 1/3 of vertebral body, significantly increasing posterior disk space height and foraminal height compared with the DLIF group. Global and segmental lumbar lordosis was greater in the DLIF group due to anterior cage position without statistical significance. In our report of L4/L5 level diseases, the OLIF technique may decrease approach-related perioperative morbidities by eliminating the risk of unwanted muscle and nerve manipulations. Using orthogonal maneuver, cage could be safely placed more posteriorly, resulting in better disk and foraminal height restoration.

  11. Reconstruction of the North Atlantic end-member of the thermohaline circulation across the Mid-Pleistocene Transition

    NASA Astrophysics Data System (ADS)

    Kim, J.; Seguí, M. J.; Yehudai, M.; Goldstein, S. L.; Pena, L. D.; Raymo, M. E.; Ford, H. L.; Haynes, L.; Farmer, J. R.; Hoenisch, B.

    2016-12-01

    The dominant periodicity of glacial and interglacial cycles shifted from 41 ky to 100 ky at 1.2-0.8 Ma, marking the Mid-Pleistocene Transition (MPT). Pena and Goldstein (Science, 2014) investigated changes in the Earth's global thermohaline circulation (THC), focusing on South Atlantic cores, and concluded that the THC experienced major disruptions between 950-850 ka (MIS 25 to 21), which generated the climatic conditions that intensified cold periods, prolonged their duration, and stabilized 100 ky cycles. However, knowledge of the coeval North Atlantic is key for interpreting data from the Middle and South Atlantic. We report Nd isotope ratios on Fe-Mn oxide encrusted foraminifera and fish debris from DSDP Site 607 (41.001N; 32.957W, 3427m) between 1.2-0.4 Ma, as a representative of the deep North Atlantic. Pre-MPT results (MIS 35-25) show interglacial ɛNd-values of -13.5 to -14.0, similar to today, and glacial-interglacial variability of 1 ɛNd-unit. Post-MPT results after MIS 19 also show interglacial ɛNd-values of -13.5 to -14.0, but greater glacial-interglacial variability of 2 ɛNd-units. Interglacial-to-glacial transitions throughout the core shift to higher ɛNd-values indicative of weakening THC, except for MIS 26, which is uniquely more negative than the neighboring interglacials, with ɛNd reaching -14.5. During the critical MPT interval of MIS 25-21 recognized by Pena and Goldstein (2014), and continuing beyond it through MIS 19, DSDP 607 ɛNd shows higher values of -11.5 to -12.5, like post-MPT glacials. Thus for the North Atlantic, from the point of view of ɛNd in DSDP 607, post-MPT and pre-MPT interglacials are similar, and post-MPT glacials and MPT glacials are similar. Moreover, comparison to the Pena and Goldstein (2014) South Atlantic data indicates that disruptions to North Atlantic overturning may have begun as early as MIS 27, and the recovery to the pre-MPT interglacial conditions may have been delayed beyond MIS 19.

  12. Systematic design methodology for robust genetic transistors based on I/O specifications via promoter-RBS libraries.

    PubMed

    Lee, Yi-Ying; Hsu, Chih-Yuan; Lin, Ling-Jiun; Chang, Chih-Chun; Cheng, Hsiao-Chun; Yeh, Tsung-Hsien; Hu, Rei-Hsing; Lin, Che; Xie, Zhen; Chen, Bor-Sen

    2013-10-27

    Synthetic genetic transistors are vital for signal amplification and switching in genetic circuits. However, it is still problematic to efficiently select the adequate promoters, Ribosome Binding Sides (RBSs) and inducer concentrations to construct a genetic transistor with the desired linear amplification or switching in the Input/Output (I/O) characteristics for practical applications. Three kinds of promoter-RBS libraries, i.e., a constitutive promoter-RBS library, a repressor-regulated promoter-RBS library and an activator-regulated promoter-RBS library, are constructed for systematic genetic circuit design using the identified kinetic strengths of their promoter-RBS components.According to the dynamic model of genetic transistors, a design methodology for genetic transistors via a Genetic Algorithm (GA)-based searching algorithm is developed to search for a set of promoter-RBS components and adequate concentrations of inducers to achieve the prescribed I/O characteristics of a genetic transistor. Furthermore, according to design specifications for different types of genetic transistors, a look-up table is built for genetic transistor design, from which we could easily select an adequate set of promoter-RBS components and adequate concentrations of external inducers for a specific genetic transistor. This systematic design method will reduce the time spent using trial-and-error methods in the experimental procedure for a genetic transistor with a desired I/O characteristic. We demonstrate the applicability of our design methodology to genetic transistors that have desirable linear amplification or switching by employing promoter-RBS library searching.

  13. Systematic design methodology for robust genetic transistors based on I/O specifications via promoter-RBS libraries

    PubMed Central

    2013-01-01

    Background Synthetic genetic transistors are vital for signal amplification and switching in genetic circuits. However, it is still problematic to efficiently select the adequate promoters, Ribosome Binding Sides (RBSs) and inducer concentrations to construct a genetic transistor with the desired linear amplification or switching in the Input/Output (I/O) characteristics for practical applications. Results Three kinds of promoter-RBS libraries, i.e., a constitutive promoter-RBS library, a repressor-regulated promoter-RBS library and an activator-regulated promoter-RBS library, are constructed for systematic genetic circuit design using the identified kinetic strengths of their promoter-RBS components. According to the dynamic model of genetic transistors, a design methodology for genetic transistors via a Genetic Algorithm (GA)-based searching algorithm is developed to search for a set of promoter-RBS components and adequate concentrations of inducers to achieve the prescribed I/O characteristics of a genetic transistor. Furthermore, according to design specifications for different types of genetic transistors, a look-up table is built for genetic transistor design, from which we could easily select an adequate set of promoter-RBS components and adequate concentrations of external inducers for a specific genetic transistor. Conclusion This systematic design method will reduce the time spent using trial-and-error methods in the experimental procedure for a genetic transistor with a desired I/O characteristic. We demonstrate the applicability of our design methodology to genetic transistors that have desirable linear amplification or switching by employing promoter-RBS library searching. PMID:24160305

  14. Is the use of minimally invasive fusion technologies associated with improved outcomes after elective interbody lumbar fusion? Analysis of a nationwide prospective patient-reported outcomes registry.

    PubMed

    McGirt, Matthew J; Parker, Scott L; Mummaneni, Praveen; Knightly, John; Pfortmiller, Deborah; Foley, Kevin; Asher, Anthony L

    2017-07-01

    Over the last decade, clinical investigators and biomedical industry groups have used significant resources to develop advanced technologies that enable less invasive spine fusions. These minimally invasive surgery (MIS) technologies often require increased expenditures by hospitals and payers. Although several small single center studies have suggested MIS technologies decrease surgical morbidity and reduce hospital stay, evidence documenting benefit from a patient perspective remains limited. Furthermore, MIS outcomes have yet to be evaluated from the perspective of multiple practice types representing the broad spectrum of US spine surgery. This study aimed to examine a population of patients who underwent one- or two-level interbody lumbar fusion diagnosed with lumbar stenosis or Grade 1 spondylolisthesis in an observational, prospective national registry for the purposes of determining how MIS and traditional open technologies affect postsurgical and patient-reported outcomes (PROs). This study used observational analysis of prospectively collected data. The sample consisted of cases from the National Neurosurgery Quality and Outcomes Database (N 2 QOD). Numeric rating scale for back and leg pain, Oswestry Disability Index, EuroQol-5D, return to work, and perioperative morbidity were the outcome measures. The N 2 QOD is a prospective PROs registry enrolling patients undergoing elective spine surgery from 60 hospitals in 27 US states via representative sampling. We analyzed the N 2 QOD aggregate dataset (2010-2014) to identify one- and two-level lumbar interbody fusion procedures performed for lumbar stenosis or Grade 1 spondylolisthesis with 12 months' follow-up where surgical instrumentation and implant types were clearly identified. Perioperative and 1-year outcomes were compared between cases performed with MIS enabling technologies versus traditional open technologies before and after propensity matching. There were 467 (24%) patients who underwent elective interbody lumbar fusion using MIS enabling technologies whereas 1,480 (76%) underwent the procedure using traditional open technologies. The MIS patients were slightly healthier (American Society of Anesthesiologists grade), had private insurance more frequently, and underwent two-level fusion less frequently. Unmatched, the MIS cohort was associated with reduced blood loss, a 0.7-day reduction in mean length of hospital stay, and 5% reduced need for post-discharge inpatient rehabilitation, but equivalent 90-day safety measures. After propensity matching, the MIS cohort remained associated with reduced blood loss and a shorter length of stay for one-level fusion (p<.05) but had equivalent length of stay for two-level fusion. Outcomes in all other 90-day safety measures were similar. In both unadjusted and propensity-matched comparison, MIS versus open technologies were associated with equivalent return to work, patient-reported pain, physical disability, and quality of life at 3 and 12 months' follow-up. In a representative sampling registry of elective interbody lumbar spine fusion procedures spanning 27 US states, nearly a quarter of procedures performed from 2010 to 2014 used minimally invasive enabling technologies. Regardless of approach, interbody lumbar fusion was associated with significant and sustained improvements in all measured health domains. When used in everyday care by a wide spectrum of spine surgeons in non-research settings, the use of MIS technologies was associated with reduced intraoperative blood loss but only a half-day reduction in mean length of hospital stay for one-level fusions. Minimally invasive surgery was not associated with any improved perioperative safety measures or 12-month outcomes. Although MIS enabling technologies may increase some in-hospital care efficiencies, MIS clinical outcomes are similar to open surgery for patients undergoing one- and two-level interbody lumbar fusions. Copyright © 2017 Elsevier Inc. All rights reserved.

  15. Stretchable transistors with buckled carbon nanotube films as conducting channels

    DOEpatents

    Arnold, Michael S; Xu, Feng

    2015-03-24

    Thin-film transistors comprising buckled films comprising carbon nanotubes as the conductive channel are provided. Also provided are methods of fabricating the transistors. The transistors, which are highly stretchable and bendable, exhibit stable performance even when operated under high tensile strains.

  16. Electrophoretic and field-effect graphene for all-electrical DNA array technology.

    PubMed

    Xu, Guangyu; Abbott, Jeffrey; Qin, Ling; Yeung, Kitty Y M; Song, Yi; Yoon, Hosang; Kong, Jing; Ham, Donhee

    2014-09-05

    Field-effect transistor biomolecular sensors based on low-dimensional nanomaterials boast sensitivity, label-free operation and chip-scale construction. Chemical vapour deposition graphene is especially well suited for multiplexed electronic DNA array applications, since its large two-dimensional morphology readily lends itself to top-down fabrication of transistor arrays. Nonetheless, graphene field-effect transistor DNA sensors have been studied mainly at single-device level. Here we create, from chemical vapour deposition graphene, field-effect transistor arrays with two features representing steps towards multiplexed DNA arrays. First, a robust array yield--seven out of eight transistors--is achieved with a 100-fM sensitivity, on par with optical DNA microarrays and at least 10 times higher than prior chemical vapour deposition graphene transistor DNA sensors. Second, each graphene acts as an electrophoretic electrode for site-specific probe DNA immobilization, and performs subsequent site-specific detection of target DNA as a field-effect transistor. The use of graphene as both electrode and transistor suggests a path towards all-electrical multiplexed graphene DNA arrays.

  17. CMOS-based carbon nanotube pass-transistor logic integrated circuits

    PubMed Central

    Ding, Li; Zhang, Zhiyong; Liang, Shibo; Pei, Tian; Wang, Sheng; Li, Yan; Zhou, Weiwei; Liu, Jie; Peng, Lian-Mao

    2012-01-01

    Field-effect transistors based on carbon nanotubes have been shown to be faster and less energy consuming than their silicon counterparts. However, ensuring these advantages are maintained for integrated circuits is a challenge. Here we demonstrate that a significant reduction in the use of field-effect transistors can be achieved by constructing carbon nanotube-based integrated circuits based on a pass-transistor logic configuration, rather than a complementary metal-oxide semiconductor configuration. Logic gates are constructed on individual carbon nanotubes via a doping-free approach and with a single power supply at voltages as low as 0.4 V. The pass-transistor logic configurarion provides a significant simplification of the carbon nanotube-based circuit design, a higher potential circuit speed and a significant reduction in power consumption. In particular, a full adder, which requires a total of 28 field-effect transistors to construct in the usual complementary metal-oxide semiconductor circuit, uses only three pairs of n- and p-field-effect transistors in the pass-transistor logic configuration. PMID:22334080

  18. Realization of Molecular-Based Transistors.

    PubMed

    Richter, Shachar; Mentovich, Elad; Elnathan, Roey

    2018-06-06

    Molecular-based devices are widely considered as significant candidates to play a role in the next generation of "post-complementary metal-oxide-semiconductor" devices. In this context, molecular-based transistors: molecular junctions that can be electrically gated-are of particular interest as they allow new modes of operation. The properties of molecular transistors composed of a single- or multimolecule assemblies, focusing on their practicality as real-world devices, concerning industry demands and its roadmap are compared. Also, the capability of the gate electrode to modulate the molecular transistor characteristics efficiently is addressed, showing that electrical gating can be easily facilitated in single molecular transistors and that gating of transistor composed of molecular assemblies is possible if the device is formed vertically. It is concluded that while the single-molecular transistor exhibits better performance on the lab-scale, its realization faces signifacant challenges when compared to those faced by transistors composed of a multimolecule assembly. © 2018 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  19. High-performance vertical organic transistors.

    PubMed

    Kleemann, Hans; Günther, Alrun A; Leo, Karl; Lüssem, Björn

    2013-11-11

    Vertical organic thin-film transistors (VOTFTs) are promising devices to overcome the transconductance and cut-off frequency restrictions of horizontal organic thin-film transistors. The basic physical mechanisms of VOTFT operation, however, are not well understood and VOTFTs often require complex patterning techniques using self-assembly processes which impedes a future large-area production. In this contribution, high-performance vertical organic transistors comprising pentacene for p-type operation and C60 for n-type operation are presented. The static current-voltage behavior as well as the fundamental scaling laws of such transistors are studied, disclosing a remarkable transistor operation with a behavior limited by injection of charge carriers. The transistors are manufactured by photolithography, in contrast to other VOTFT concepts using self-assembled source electrodes. Fluorinated photoresist and solvent compounds allow for photolithographical patterning directly and strongly onto the organic materials, simplifying the fabrication protocol and making VOTFTs a prospective candidate for future high-performance applications of organic transistors. Copyright © 2013 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  20. Analogy of transistor function with modulating photonic band gap in electromagnetically induced grating

    PubMed Central

    Wang, Zhiguo; Ullah, Zakir; Gao, Mengqin; Zhang, Dan; Zhang, Yiqi; Gao, Hong; Zhang, Yanpeng

    2015-01-01

    Optical transistor is a device used to amplify and switch optical signals. Many researchers focus on replacing current computer components with optical equivalents, resulting in an optical digital computer system processing binary data. Electronic transistor is the fundamental building block of modern electronic devices. To replace electronic components with optical ones, an equivalent optical transistor is required. Here we compare the behavior of an optical transistor with the reflection from a photonic band gap structure in an electromagnetically induced transparency medium. A control signal is used to modulate the photonic band gap structure. Power variation of the control signal is used to provide an analogy between the reflection behavior caused by modulating the photonic band gap structure and the shifting of Q-point (Operation point) as well as amplification function of optical transistor. By means of the control signal, the switching function of optical transistor has also been realized. Such experimental schemes could have potential applications in making optical diode and optical transistor used in quantum information processing. PMID:26349444

  1. Analogy of transistor function with modulating photonic band gap in electromagnetically induced grating

    NASA Astrophysics Data System (ADS)

    Wang, Zhiguo; Ullah, Zakir; Gao, Mengqin; Zhang, Dan; Zhang, Yiqi; Gao, Hong; Zhang, Yanpeng

    2015-09-01

    Optical transistor is a device used to amplify and switch optical signals. Many researchers focus on replacing current computer components with optical equivalents, resulting in an optical digital computer system processing binary data. Electronic transistor is the fundamental building block of modern electronic devices. To replace electronic components with optical ones, an equivalent optical transistor is required. Here we compare the behavior of an optical transistor with the reflection from a photonic band gap structure in an electromagnetically induced transparency medium. A control signal is used to modulate the photonic band gap structure. Power variation of the control signal is used to provide an analogy between the reflection behavior caused by modulating the photonic band gap structure and the shifting of Q-point (Operation point) as well as amplification function of optical transistor. By means of the control signal, the switching function of optical transistor has also been realized. Such experimental schemes could have potential applications in making optical diode and optical transistor used in quantum information processing.

  2. Society of Laparoendoscopic Surgeons

    MedlinePlus

    ... physician orientation and patient outcome. Minimally Invasive Surgery Week 2018 MISWeek – The #1 MIS Meeting. Minimally Invasive ... Pacific Rim, Asian Oceanic regions … Minimally Invasive Surgery Week 2017 MISWeek – The #1 MIS Meeting. Minimally Invasive ...

  3. Distributed-Memory Fast Maximal Independent Set

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Kanewala Appuhamilage, Thejaka Amila J.; Zalewski, Marcin J.; Lumsdaine, Andrew

    The Maximal Independent Set (MIS) graph problem arises in many applications such as computer vision, information theory, molecular biology, and process scheduling. The growing scale of MIS problems suggests the use of distributed-memory hardware as a cost-effective approach to providing necessary compute and memory resources. Luby proposed four randomized algorithms to solve the MIS problem. All those algorithms are designed focusing on shared-memory machines and are analyzed using the PRAM model. These algorithms do not have direct efficient distributed-memory implementations. In this paper, we extend two of Luby’s seminal MIS algorithms, “Luby(A)” and “Luby(B),” to distributed-memory execution, and we evaluatemore » their performance. We compare our results with the “Filtered MIS” implementation in the Combinatorial BLAS library for two types of synthetic graph inputs.« less

  4. Applying management information systems to staffing.

    PubMed

    Hanson, R L

    1982-10-01

    A management information system (MIS) is a tool for managing resources effectively. After reviewing some concepts and principles for effective data management, Hanson clearly applies the concepts to nurse staffing systems, which manage human resources. He defines a seven-step process for establishing an MIS, from defining the management objective to implementing the system. Pointing out that an MIS need not be computerized to be effective, Hanson presents a positive perspective and clarifies some often-misconceived notions about management information systems and the paper printouts they generate. In the next issue of JONA, a second article by Hanson will take a more detailed look at the variety, use, and usefulness of staffing statistics available from an MIS for staffing. These articles are based on material in a forthcoming book, Management Systems for Nursing Service Staffing, to be published by Aspen Systems Corporation, Rockville, Maryland.

  5. Additive Manufacturing Consolidation of Low-Cost Water Atomized Steel Powder Using Micro-Induction Sintering

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Carter, William G.; Rios, Orlando; U

    ORNL worked with Grid Logic Inc to demonstrate micro induction sintering (MIS) and binder decomposition of steel powders. It was shown that MIS effectively emits spatially confined electromagnetic energy that is directly coupled to metallic powders resulting in resistive heating of individual particles. The non-uniformity of particle morphology and distribution of the water atomized steel powders resulted in inefficient transfer of energy. It was shown that adhering the particles together using polymer binders resulted in more efficient coupling. Using the MIS processes, debinding and sintering could be done in a single step. When combined with another system, such as binder-jet,more » this could reduce the amount of required post-processing. An invention disclosure was filed on hybrid systems that use MIS to reduce the amount of required post-processing.« less

  6. Further study of inversion layer MIS solar cells

    NASA Technical Reports Server (NTRS)

    Ho, Fat Duen

    1992-01-01

    Many inversion layer metal-insulator-semiconductor (IL/MIS) solar cells have been fabricated. As of today, the best cell fabricated by us has a 9.138 percent AMO efficiency, with FF = 0.641, V(sub OC) = 0.557 V, and I(sub SC) = 26.9 micro A. Efforts made for fabricating an IL/MOS solar cell with reasonable efficiencies are reported. The more accurate control of the thickness of the thin layer of oxide between aluminum and silicon of the MIS contacts has been achieved by using two different process methods. Comparison of these two different thin oxide processings is reported. The effects of annealing time of the sample are discussed. The range of the resistivity of the substrates used in the IL cell fabrication is experimentally estimated. Theoretical study of the MIS contacts under dark conditions is addressed.

  7. A retinaculum-sparing surgical approach preserves porcine stifle joint cartilage in an experimental animal model of cartilage repair.

    PubMed

    Bonadio, Marcelo B; Friedman, James M; Sennett, Mackenzie L; Mauck, Robert L; Dodge, George R; Madry, Henning

    2017-12-01

    This study compares a traditional parapatellar retinaculum-sacrificing arthrotomy to a retinaculum-sparing arthrotomy in a porcine stifle joint as a cartilage repair model. Surgical exposure of the femoral trochlea of ten Yucatan pigs stifle joint was performed using either a traditional medial parapatellar approach with retinaculum incision and luxation of the patella (n = 5) or a minimally invasive (MIS) approach which spared the patellar retinaculum (n = 5). Both classical and MIS approaches provided adequate access to the trochlea, enabling the creation of cartilage defects without difficulties. Four full thickness, 4 mm circular full-thickness cartilage defects were created in each trochlea. There were no intraoperative complications observed in either surgical approach. All pigs were allowed full weight-bearing and full range of motion immediately postoperatively and were euthanized between 2 and 3 weeks. The traditional approach was associated with increased cartilage wear compared to the MIS approach. Two blinded raters performed gross evaluation of the trochlea cartilage surrounding the defects according to the modified ICRS cartilage injury classification. The traditional approach cartilage received a significantly worse score than the MIS approach group from both scorers (3.2 vs 0.8, p = 0.01 and 2.8 vs 0, p = 0.005 respectively). The MIS approach results in less damage to the trochlear cartilage and faster return to load bearing activities. As an arthrotomy approach in the porcine model, MIS is superior to the traditional approach.

  8. Resolution of donor non-alcoholic fatty liver disease following liver transplantation.

    PubMed

    Posner, Andrew D; Sultan, Samuel T; Zaghloul, Norann A; Twaddell, William S; Bruno, David A; Hanish, Steven I; Hutson, William R; Hebert, Laci; Barth, Rolf N; LaMattina, John C

    2017-09-01

    Transplant surgeons conventionally select against livers displaying high degrees (>30%) of macrosteatosis (MaS), out of concern for primary non-function or severe graft dysfunction. As such, there is relatively limited experience with such livers, and the natural history remains incompletely characterized. We present our experience of transplanted livers with high degrees of MaS and microsteatosis (MiS), with a focus on the histopathologic and clinical outcomes. Twenty-nine cases were identified with liver biopsies available from both the donor and the corresponding liver transplant recipient. Donor liver biopsies displayed either MaS or MiS ≥15%, while all recipients received postoperative liver biopsies for cause. The mean donor MaS and MiS were 15.6% (range 0%-60%) and 41.3% (7.5%-97.5%), respectively. MaS decreased significantly from donor (M=15.6%) to recipient postoperative biopsies (M=0.86%), P<.001. Similarly, MiS decreased significantly from donor biopsies (M=41.3%) to recipient postoperative biopsies (M=1.8%), P<.001. At a median of 68 days postoperatively (range 4-384), full resolution of MaS and MiS was observed in 27 of 29 recipients. High degrees of MaS and MiS in donor livers resolve in recipients following liver transplantation. Further insight into the mechanisms responsible for treating fatty liver diseases could translate into therapeutic targets. © 2017 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

  9. Environmental impact of minimally invasive surgery in the United States: an estimate of the carbon dioxide footprint.

    PubMed

    Power, Nicholas E; Silberstein, Jonathan L; Ghoneim, Tarek P; Guillonneau, Bertrand; Touijer, Karim A

    2012-12-01

    To attempt to quantitate the carbon footprint of minimally invasive surgery (MIS) through approximated scope 1 to 3 CO(2) emissions to identify its potential role in global warming. To estimate national usage, we determined the number of inpatient and outpatient MIS procedures using International Classification of Diseases, ninth revision-clinical modification codes for all MIS procedures in a 2009 sample collected in national databases. Need for surgery was considered essential, and therefore traditional open surgery was used as the comparator. Scope 1 (direct) CO(2) emissions resulting from CO(2) gas used for insufflation were based on both escaping procedural CO(2) and metabolic CO(2) eliminated via respiration. Scopes 2 and 3 (indirect) emissions related to capture, compression, and transportation of CO(2) to hospitals and the disposal of single-use equipment not used in open surgery were calculated. The total CO(2) emissions were calculated to be 355,924 tonnes/year. For perspective, if MIS in the United States was considered a country, it would rank 189 th on the United Nations 2008 list of countries' carbon emissions per year. Limitations include the inability to account for uncertainty using the various models and tools for approximating CO(2) emissions. CO(2) emission of MIS in the United States may have a significant environmental impact. This is the first attempt to quantify CO(2) emissions related to MIS in the United States. Strategies for reduction, while maintaining high quality medical care, should be considered.

  10. Current control circuitry

    DOEpatents

    Taubman, Matthew S [Richland, WA

    2005-03-15

    Among the embodiments of the present invention is an apparatus that includes a transistor (30), a servo device (40), and a current source (50). The servo device (40) is operable to provide a common base mode of operation of the transistor (30) by maintaining an approximately constant voltage level at the transistor base (32b). The current source (150) is operable to provide a bias current to the transistor (30). A first device (24) provides an input signal to an electrical node (70) positioned between the emitter (32e) of the transistor (30) and the current source (50). A second device (26) receives an output signal from the collector (32c) of the transistor (30).

  11. Comparison of junctionless and inversion-mode p-type metal-oxide-semiconductor field-effect transistors in presence of hole-phonon interactions

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Dib, E., E-mail: elias.dib@for.unipi.it; Carrillo-Nuñez, H.; Cavassilas, N.

    Junctionless transistors are being considered as one of the alternatives to conventional metal-oxide field-effect transistors. In this work, it is then presented a simulation study of silicon double-gated p-type junctionless transistors compared with its inversion-mode counterpart. The quantum transport problem is solved within the non-equilibrium Green's function formalism, whereas hole-phonon interactions are tackled by means of the self-consistent Born approximation. Our findings show that junctionless transistors should perform as good as a conventional transistor only for ultra-thin channels, with the disadvantage of requiring higher supply voltages in thicker channel configurations.

  12. Optimization of Vertical Double-Diffused Metal-Oxide Semiconductor (VDMOS) Power Transistor Structure for Use in High Frequencies and Medical Devices

    PubMed Central

    Farhadi, Rozita; Farhadi, Bita

    2014-01-01

    Power transistors, such as the vertical, double-diffused, metal-oxide semiconductor (VDMOS), are used extensively in the amplifier circuits of medical devices. The aim of this research was to construct a VDMOS power transistor with an optimized structure to enhance the operation of medical devices. First, boron was implanted in silicon by implanting unclamped inductive switching (UIS) and a Faraday shield. The Faraday shield was implanted in order to replace the gate-field parasitic capacitor on the entry part of the device. Also, implanting the UIS was used in order to decrease the effect of parasitic bipolar junction transistor (BJT) of the VDMOS power transistor. The research tool used in this study was Silvaco software. By decreasing the transistor entry resistance in the optimized VDMOS structure, power losses and noise at the entry of the transistor were decreased, and, by increasing the breakdown voltage, the lifetime of the VDMOS transistor lifetime was increased, which resulted in increasing drain flow and decreasing Ron. This consequently resulted in enhancing the operation of high-frequency medical devices that use transistors, such as Radio Frequency (RF) and electrocardiograph machines. PMID:25763152

  13. Optimization of Vertical Double-Diffused Metal-Oxide Semiconductor (VDMOS) Power Transistor Structure for Use in High Frequencies and Medical Devices.

    PubMed

    Farhadi, Rozita; Farhadi, Bita

    2014-01-01

    Power transistors, such as the vertical, double-diffused, metal-oxide semiconductor (VDMOS), are used extensively in the amplifier circuits of medical devices. The aim of this research was to construct a VDMOS power transistor with an optimized structure to enhance the operation of medical devices. First, boron was implanted in silicon by implanting unclamped inductive switching (UIS) and a Faraday shield. The Faraday shield was implanted in order to replace the gate-field parasitic capacitor on the entry part of the device. Also, implanting the UIS was used in order to decrease the effect of parasitic bipolar junction transistor (BJT) of the VDMOS power transistor. The research tool used in this study was Silvaco software. By decreasing the transistor entry resistance in the optimized VDMOS structure, power losses and noise at the entry of the transistor were decreased, and, by increasing the breakdown voltage, the lifetime of the VDMOS transistor lifetime was increased, which resulted in increasing drain flow and decreasing Ron. This consequently resulted in enhancing the operation of high-frequency medical devices that use transistors, such as Radio Frequency (RF) and electrocardiograph machines.

  14. Hydrological variability in the Northern Levant: a 250 ka multiproxy record from the Yammoûneh (Lebanon) sedimentary sequence

    NASA Astrophysics Data System (ADS)

    Gasse, F.; Vidal, L.; Develle, A.-L.; van Campo, E.

    2011-11-01

    The Levant is a key region in terms of both long-term hydroclimate dynamics and human cultural evolution. Our understanding of the regional response to glacial-interglacial boundary conditions is limited by uncertainties in proxy-data interpretation and the lack of long-term records from different geographical settings. The present paper provides a 250 ka paleoenvironmental reconstruction based on a multi-proxy approach from northern Levant, derived from a 36 m lacustrine-palustrine sequence cored in the small intra-mountainous karstic Yammoûneh basin from northern Lebanon. We combined time series of sediment properties, paleovegetation, and carbonate oxygen isotopes (δc), to yield a comprehensive view of paleohydrologic-paleoclimatic fluctuations in the basin over the two last glacial-interglacial cycles. Integration of all available proxies shows that Interglacial maxima (early-mid MIS 7, MIS 5.5 and early MIS 1) experienced relatively high effective moisture, evidenced by the dominance of forested landscapes (although with different forest types) associated with authigenic carbonate sedimentation in a productive waterbody. Synchronous and steep δc increases can be reconciled with enhanced mean annual moisture when changes in seasonality are taken into account. During Glacials periods (MIS 2 and MIS 6), open vegetation tends to replace the forests, favouring local erosion and detrital sedimentation. However, all proxy data reveal an overall wetting during MIS 6, while a drying trend took place during MIS4-2, leading to extremely harsh LGM conditions possibly linked to water storage as ice in the surrounding highlands. Over the past 250 ka, the Yammoûneh record shows an overall decrease in local effective water, coincident with a weakening of seasonal insolation contrasts linked to the decreasing amplitude of the eccentricity cycle. The Yammoûneh record is roughly consistent with long-term climatic fluctuations in the northeastern Mediterranean region (except during MIS 6). It suggests that the role of seasonality on effective moisture, already highlighted for MIS 1, also explains older interglacial climate. The Yammoûneh record shares some features with speleothem isotope records of western Israel, while the Dead Sea basin generally evolved in opposite directions. Changes in atmospheric circulation, regional topographic patterns and site-specific hydrological factors are invoked as potential causes of spatial heterogeneities. Further work is needed to refine the Yammoûneh chronology, better understand its functioning through hydrological and climate modelling, and acquire other long records from northern Levant to disentangle the relative effects of local versus regional factors.

  15. A MIS 9/MIS 8 speleothem record of hydrological variability from Macedonia (F.Y.R.O.M.)

    NASA Astrophysics Data System (ADS)

    Regattieri, Eleonora; Zanchetta, Giovanni; Isola, Ilaria; Bajo, Petra; Perchiazzi, Natale; Drysdale, Russell N.; Boschi, Chiara; Hellstrom, John C.; Francke, Alexander; Wagner, Bernd

    2018-03-01

    The period corresponding to Marine Isotope Stages 9 (MIS 9) offers the opportunity to study orbital and sub-orbital scale climate variability under boundary conditions different from those of better studied intervals such as the Holocene and the Last Interglacial. Yet, it is poorly represented in independently-dated continental archives around the Mediterranean Region. Here, we present a speleothem stable isotope record (δ18O and δ13C) from the Former Yugoslavian Republic of Macedonia (F.Y.R.O.M., southern Balkans), which consists of two periods of growth broadly covering the ca. 332 to 292 ka and the ca. 264 to 248 ka intervals (MIS 9e-b and late MIS 8). We interpret the speleothem δ18O as mostly related to regional hydrology, with variations that can be interpreted as due to changes in rainfall amount, with higher/lower values associated to drier/wetter condition. This interpretation is corroborated by a change in mineralogical composition between aragonite and calcite at ca. 328 ka, which marks increasing precipitation at the onset of MIS 9 and occurs within a trend of decreasing δ18O values. Also the comparison with the multiproxy climate record available from the nearby Lake Ohrid seems to support the proposed interpretation. The MIS 9e interglacial appears to be characterized by wettest conditions between ca. 326 and 321 ka, i.e. lasting ca. 5 kyr. Decreasing precipitation and enhanced millennial scale variability matches the glacial inception (MIS9 d to b), with drier events at ca. 319 ka (ca. 2 kyr long) and 310 ka (ca. 1 kyr long), and a major rainfall reduction between 306 and 298 ka. The latter is followed by a prominent wetter period between 298 and 295 ka, for which carbon data values suggest high infiltration rate. Rainfall decreases again after 295 ka, and remain low until the growth interruption at ca. 292 ka. Resumption of the growth and progressive soil development, expressed by the carbon isotope record, occurred during the late part of MIS 8. Despite the rather high temporal uncertainty (average 6 ka), the speleothem hydrological record complements the environmental information provided by the Lake Ohrid record and also fits well to the framework of regional and extra-regional variability, showing similarities with pollen records from southern and western Europe, both at orbital and at sub-orbital time scale.

  16. Triple-mode single-transistor graphene amplifier and its applications.

    PubMed

    Yang, Xuebei; Liu, Guanxiong; Balandin, Alexander A; Mohanram, Kartik

    2010-10-26

    We propose and experimentally demonstrate a triple-mode single-transistor graphene amplifier utilizing a three-terminal back-gated single-layer graphene transistor. The ambipolar nature of electronic transport in graphene transistors leads to increased amplifier functionality as compared to amplifiers built with unipolar semiconductor devices. The ambipolar graphene transistors can be configured as n-type, p-type, or hybrid-type by changing the gate bias. As a result, the single-transistor graphene amplifier can operate in the common-source, common-drain, or frequency multiplication mode, respectively. This in-field controllability of the single-transistor graphene amplifier can be used to realize the modulation necessary for phase shift keying and frequency shift keying, which are widely used in wireless applications. It also offers new opportunities for designing analog circuits with simpler structure and higher integration densities for communications applications.

  17. T-gate aligned nanotube radio frequency transistors and circuits with superior performance.

    PubMed

    Che, Yuchi; Lin, Yung-Chen; Kim, Pyojae; Zhou, Chongwu

    2013-05-28

    In this paper, we applied self-aligned T-gate design to aligned carbon nanotube array transistors and achieved an extrinsic current-gain cutoff frequency (ft) of 25 GHz, which is the best on-chip performance for nanotube radio frequency (RF) transistors reported to date. Meanwhile, an intrinsic current-gain cutoff frequency up to 102 GHz is obtained, comparable to the best value reported for nanotube RF transistors. Armed with the excellent extrinsic RF performance, we performed both single-tone and two-tone measurements for aligned nanotube transistors at a frequency up to 8 GHz. Furthermore, we utilized T-gate aligned nanotube transistors to construct mixing and frequency doubling analog circuits operated in gigahertz frequency regime. Our results confirm the great potential of nanotube-based circuit applications and indicate that nanotube transistors are promising building blocks in high-frequency electronics.

  18. How CEOs use management information systems for strategy implementation in hospitals.

    PubMed

    Naranjo-Gil, David; Hartmann, Frank

    2007-04-01

    Institutional and market changes seem to force hospitals across the Western world to revitalize their corporate strategies towards more cost efficiency on the one hand, and more flexibility towards customer demands on the other hand. Hospitals, however, apparently differ in the extent to which they are able to implement such strategies effectively. This paper explores whether these different levels of effectiveness depend on how hospitals' top managers' use of the available management information systems (MIS). Based on data obtained from the 218 CEOs of public hospitals in Spain, we analyze how CEOs' professional and educational backgrounds affect their use of MIS, and how the use of the MIS subsequently supports or inhibits the implementation of these strategic goals. The results indicate that CEOs with a predominant clinical background focus more on non-financial information for decision-making and prefer an interactive style of using MIS, which together support flexibility strategies. CEOs with a predominant administrative background seem more effective in establishing cost-reduction strategies, through their larger inclination to emphasize financial information in combination with a diagnostic use of the MIS. Implications for the strategic management of hospitals are outlined.

  19. A Modified Protocol with Improved Detection Rate for Mis-Matched Donor HLA from Low Quantities of DNA in Urine Samples from Kidney Graft Recipients.

    PubMed

    Kwok, Janette; Choi, Leo C W; Ho, Jenny C Y; Chan, Gavin S W; Mok, Maggie M Y; Lam, Man-Fei; Chak, Wai-Leung; Cheuk, Au; Chau, Ka-Foon; Tong, Matthew; Chan, Kwok-Wah; Chan, Tak-Mao

    2016-01-01

    Urine from kidney transplant recipient has proven to be a viable source for donor DNA. However, an optimized protocol would be required to determine mis-matched donor HLA specificities in view of the scarcity of DNA obtained in some cases. In this study, fresh early morning urine specimens were obtained from 155 kidney transplant recipients with known donor HLA phenotype. DNA was extracted and typing of HLA-A, B and DRB1 loci by polymerase chain reaction-specific sequence primers was performed using tailor-made condition according to the concentration of extracted DNA. HLA typing of DNA extracted from urine revealed both recipient and donor HLA phenotypes, allowing the deduction of the unknown donor HLA and hence the degree of HLA mis-match. By adopting the modified procedures, mis-matched donor HLA phenotypes were successfully deduced in all of 35 tested urine samples at DNA quantities spanning the range of 620-24,000 ng. This urine-based method offers a promising and reliable non-invasive means for the identification of mis-matched donor HLA antigens in kidney transplant recipients with unknown donor HLA phenotype or otherwise inadequate donor information.

  20. Temperature Dependences of the Product of the Differential Resistance by the Area in MIS-Structures Based on Cd x Hg1- x Te Grown by Molecularbeam Epitaxy on Alternative Si and GaAs Substrates

    NASA Astrophysics Data System (ADS)

    Voitsekhovskii, A. V.; Nesmelov, S. N.; Dzyadukh, S. M.; Varavin, V. S.; Vasil'ev, V. V.; Dvoretskii, S. A.; Mikhailov, N. N.; Yakushev, M. V.; Sidorov, G. Yu.

    2017-06-01

    In a temperature range of 9-200 K, temperature dependences of the differential resistance of space-charge region in the strong inversion mode are experimentally studied for MIS structures based on CdxHg1-xTe (x = 0.22-0.40) grown by molecular-beam epitaxy. The effect of various parameters of structures: the working layer composition, the type of a substrate, the type of insulator coating, and the presence of a near-surface graded-gap layer on the value of the product of differential resistance by the area is studied. It is shown that the values of the product RSCRA for MIS structures based on n-CdHgTe grown on a Si(013) substrate are smaller than those for structures based on the material grown on a GaAs(013) substrate. The values of the product RSCRA for MIS structures based on p-CdHgTe grown on a Si(013) substrate are comparable with the value of the analogous parameter for MIS structures based on p-CdHgTe grown on a GaAs(013) substrate.

  1. An ostracode based paleolimnologic and paleohydrologic history of Death Valley: 200 to 0 ka

    USGS Publications Warehouse

    Forester, R.M.; Lowenstein, T.K.; Spencer, R.J.

    2005-01-01

    Death Valley, a complex tectonic and hydrologic basin, was cored from its lowest surface elevation to a depth of 186 m. The sediments range from bedded primary halite to black muds. Continental ostracodes found in the black muds indicate that those sediments were deposited in a variety of hydrologic settings ranging from deep, relatively fresh water to shallow saline lakes to spring discharge supported wetlands. The alkaline-enriched, calcium-depleted paleolake waters indicate extrabasinal streamflow and basin-margin spring discharge. The alkaline-depleted, calcium-enriched paleowetland waters indicate intrabasinal spring discharge. During Marine Isotope Stage 6 (MIS 6, ca. 180-140 ka) the hydrologic settings were highly variable, implying that complex relations existed between climate and basin hydrology. Termination II (MIS 6 to MIS 5E) was a complex multicyclic sequence of paleoenvironments, implying that climates oscillated between high and low effective moisture. MIS 4 (ca. 73-61 ka) was a spring discharge supported wetland complex. During MIS 2 (ca. 20-12 ka) the hydrologic settings were variable, although they are not fully understood because some black muds deposited during that time were lost during coring. ?? 2005 Geological Society of America.

  2. Real-time geometry-aware augmented reality in minimally invasive surgery.

    PubMed

    Chen, Long; Tang, Wen; John, Nigel W

    2017-10-01

    The potential of augmented reality (AR) technology to assist minimally invasive surgery (MIS) lies in its computational performance and accuracy in dealing with challenging MIS scenes. Even with the latest hardware and software technologies, achieving both real-time and accurate augmented information overlay in MIS is still a formidable task. In this Letter, the authors present a novel real-time AR framework for MIS that achieves interactive geometric aware AR in endoscopic surgery with stereo views. The authors' framework tracks the movement of the endoscopic camera and simultaneously reconstructs a dense geometric mesh of the MIS scene. The movement of the camera is predicted by minimising the re-projection error to achieve a fast tracking performance, while the three-dimensional mesh is incrementally built by a dense zero mean normalised cross-correlation stereo-matching method to improve the accuracy of the surface reconstruction. The proposed system does not require any prior template or pre-operative scan and can infer the geometric information intra-operatively in real time. With the geometric information available, the proposed AR framework is able to interactively add annotations, localisation of tumours and vessels, and measurement labelling with greater precision and accuracy compared with the state-of-the-art approaches.

  3. ESR and 230Th/234U dating of speleothems from Aladağlar Mountain Range (AMR) in Turkey

    NASA Astrophysics Data System (ADS)

    Ulusoy, Ülkü; Anbar, Gül; Bayarı, Serdar; Uysal, Tonguç

    2014-03-01

    Electron spin resonance (ESR) and 230Th/234U ages of speleothem samples collected from karstic caves located around 3000 m elevation in the Aladağlar Mountain Range (AMR), south-central Turkey, were determined in order to provide new insight and information regarding late Pleistocene climate. ESR ages were validated with the 230Th/234U ages of test samples. The ESR ages of 21 different layers of six speleothem samples were found to range mostly between about 59 and 4 ka, which cover the Marine Oxygen Isotope Stages (MIS) MIS 3 to MIS 1. Among all, only six layers appear to have deposited during MIS 8 and 5. Most of the samples dated were deposited during the late glacial stage (MIS 2). It appears that a cooler climate with a perennial and steady recharge was more conducive to speleothem development rather than a warmer climate with seasonal recharge in the AMR during the late Quaternary. This argument supports previous findings that suggest a two -fold increase in last glacial maximum mean precipitation in Turkey with respect to the present value.

  4. Self-protecting transistor oscillator for treating animal tissues

    DOEpatents

    Doss, James D.

    1980-01-01

    A transistor oscillator circuit wherein the load current applied to animal tissue treatment electrodes is fed back to the transistor. Removal of load is sensed to automatically remove feedback and stop oscillations. A thermistor on one treatment electrode senses temperature, and by means of a control circuit controls oscillator transistor current.

  5. Development and Experimental Evaluation of an Automated Multi-Media Course on Transistors.

    ERIC Educational Resources Information Center

    Whitted, J.H., Jr.; And Others

    A completely automated multi-media self-study program for teaching a portion of electronic solid-state fundamentals was developed. The subject matter areas included were fundamental theory of transistors, transistor amplifier fundamentals, and simple mathematical analysis of transistors including equivalent circuits, parameters, and characteristic…

  6. EDITORIAL: Reigniting innovation in the transistor Reigniting innovation in the transistor

    NASA Astrophysics Data System (ADS)

    Demming, Anna

    2012-09-01

    Today the transistor is integral to the electronic circuitry that wires our lives. When Bardeen and Brattain first observed an amplified signal by connecting electrodes to a germanium crystal they saw that their 'semiconductor triode' could prove a useful alternative to the more cumbersome vacuum tubes used at the time [1]. But it was perhaps William Schottky who recognized the extent of the transistor's potential. A basic transistor has three or more terminals and current across one pair of terminals can switch or amplify current through another pair. Bardeen, Brattain and Schottky were jointly awarded a Nobel Prize in 1956 'for their researches on semiconductors and their discovery of the transistor effect' [2]. Since then many new forms of the transistor have been developed and understanding of the underlying properties is constantly advancing. In this issue Chen and Shih and colleagues at Taiwan National University and Drexel University report a pyroelectrics transistor. They show how a novel optothermal gating mechanism can modulate the current, allowing a range of developments in nanoscale optoelectronics and wireless devices [3]. The explosion of interest in nanoscale devices in the 1990s inspired electronics researchers to look for new systems that can act as transistors, such as carbon nanotube [4] and silicon nanowire [5] transistors. Generally these transistors function by raising and lowering an energy barrier of kBT -1, but researchers in the US and Canada have demonstrated that the quantum interference between two electronic pathways through aromatic molecules can also modulate the current flow [6]. The device has advantages for further miniaturization where energy dissipation in conventional systems may eventually cause complications. Interest in transistor technology has also led to advances in fabrication techniques for achieving high production quantities, such as printing [7]. Researchers in Florida in the US demonstrated field effect transistor behaviour in devices fabricated from chemically reduced graphene oxide. The work provided an important step forward for graphene electronics, which has been hampered by difficulties in scaling up the mechanical exfoliation techniques required to produce the high-quality graphene often needed for functioning devices [8]. In Sweden, researchers have developed a transistor design that they fabricate using standard III-V parallel processing, which also has great promise for scaling up production. Their transistor is based on a vertical array of InAs nanowires, which provide high electron mobility and the possibility of high-speed and low-power operation [9]. Different fabrication techniques and design parameters can influence the properties of transistors. Researchers in Belgium used a new method based on high-vacuum scanning spreading resistance microscopy to study the effect of diameter on carrier profile in nanowire transistors [10]. They then used experimental data and simulations to gain a better understanding of how this influenced the transistor performance. In Japan, Y Ohno and colleagues at Nagoya University have reported how atomic layer deposition of an insulating layer of HfO2 on carbon nanotube field effect transistors can change the carrier from p-type to n-type [11]. Carrier type switching—'ambipolar behaviour'—and hysteresis of carbon nanotube network transistors can make achieving reliable device performance challenging. However studies have also suggested that the hysteretic properties may be exploited in non-volatile memory applications. A collaboration of researchers in Italy and the US demonstrated transistor and memory cell behaviour in a system based on a carbon nanotube network [13]. Their device had relatively fast programming, good endurance and the charge retention was successfully enhanced by limiting exposure to air. Progress in understanding transistor behaviour has inspired other innovations in device applications. Nanowires are notoriously sensitive to gases such as CO, opening opportunities for applications in sensing using one-dimensional nanostructure transistors [12]. The pyroelectric transistor reported in this issue represents an intriguing development for device applications of this versatile and ubiquitous electronics component [3]. As the researchers point out, 'By combining the photocurrent feature and optothermal gating effect, the wide range of response to light covering ultraviolet and infrared radiation can lead to new nanoscale optoelectronic devices that are suitable for remote or wireless applications.' In nanotechnology research and development, often the race is on to achieve reliable device behaviour in the smallest possible systems. But sometimes it is the innovations in the approach used that revolutionize technology in industry. The pyroelectric transistor reported in this issue is a neat example of the ingenious innovations in this field of research. While in research the race is never really over, as this work demonstrates the journey itself remains an inspiration. References [1] Bardeen J and Brattain W H 1948 The transistor, a semi-conductor triode Phys. Rev 74 230-1 [2] Shockley W B, Bardeen J and Brattain W H 1956 The nobel prize in physics www.nobelprize.org/nobel_prizes/physics/laureates/1956/# [3] Hsieh C-Y, Lu M-L, Chen J-Y, Chen Y-T, Chen Y-F, Shih W Y and Shih W-H 2012 Single ZnO nanowire-PZT optothermal field effect transistors Nanotechnology 23 355201 [4] Tans S J, Verschueren A R M and Dekker C 1998 Room-temperature transistor based on a single carbon nanotube Nature 393 49-52 [5] Cui Y, Zhong Z, Wang D, Wang W U and Lieber C M 2003 High performance silicon nanowire field effect transistors Nano Lett. 3 149-52 [6]Stafford C A, Cardamone D M and Mazumdar S 2007 The quantum interference effect transistor Nanotechnology 18 424014 [7] Garnier F, Hajlaoui R, Yassar A and Srivastava P 1994 All-polymer field-effect transistor realized by printing techniques Science 265 1684-6 [8] Joung D, Chunder A, Zhai L and Khondaker S I 2010 High yield fabrication of chemically reduced graphene oxide field effect transistors by dielectrophoresis Nanotechnology 21 165202 [9] Bryllert T, Wernersson L-E, L¨owgren T and Samuelson L 2006 Vertical wrap-gated nanowire transistors Nanotechnology 17 S227-30 [10] Schulze A et al 2011 Observation of diameter dependent carrier distribution in nanowire-based transistors Nanotechnology 22 185701 [11] Moriyama N, Ohno Y, Kitamura T, Kishimoto S and Mizutani T 2010 Change in carrier type in high-k gate carbon nanotube field-effect transistors by interface fixed charges Nanotechnology 21 165201 [12] Bartolomeo A D, Rinzan M, Boyd A K, Yang Y, Guadagno L, Giubileo F and Barbara P 2010 Electrical properties and memory effects of field-effect transistors from networks of single-and double-walled carbon nanotubes Nanotechnology 21 115204 [13] Liao L et al 2009 Multifunctional CuO nanowire devices: P-type field effect transistors and CO gas sensors Nanotechnology 20 085203

  7. 49 CFR 219.800 - Annual reports.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... perform a service for the railroad. (b) As a railroad, you must use the Management Information System (MIS... submission to FRA. For information on where to submit MIS forms and for the electronic version of the form...

  8. Method and Circuit for Injecting a Precise Amount of Charge onto a Circuit Node

    NASA Technical Reports Server (NTRS)

    Hancock, Bruce R. (Inventor)

    2016-01-01

    A method and circuit for injecting charge into a circuit node, comprising (a) resetting a capacitor's voltage through a first transistor; (b) after the resetting, pre-charging the capacitor through the first transistor; and (c) after the pre-charging, further charging the capacitor through a second transistor, wherein the second transistor is connected between the capacitor and a circuit node, and the further charging draws charge through the second transistor from the circuit node, thereby injecting charge into the circuit node.

  9. A PWM transistor inverter for an ac electric vehicle drive

    NASA Technical Reports Server (NTRS)

    Slicker, J. M.

    1981-01-01

    A prototype system consisting of closely integrated motor, inverter, and transaxle has been built in order to demonstrate the feasibility of a three-phase ac transistorized inverter for electric vehicle applications. The microprocessor-controlled inverter employs monolithic power transistors to drive an oil-cooled, three-phase induction traction motor at a peak output power of 30 kW from a 144 V battery pack. Transistor safe switching requirements are discussed, and a circuit is presented for recovering trapped snubber inductor energy at transistor turn-off.

  10. An Introduction to the IP/PCT Model Implementation in IPME

    DTIC Science & Technology

    2011-03-01

    perceptuel (TCP) mis en œuvre dans le logiciel Environnement intégré de modélisation des performances (EIMP) par Micro Analysis and Design. Ce...de la théorie du contrôle perceptuel (TCP) mis en œuvre dans le logiciel Environnement intégré de modélisation des performances (EIMP) par Micro...modèles de traitement de l’information (TI) et de la théorie du contrôle perceptuel (TCP) mis en œuvre dans le logiciel Environnement intégré de

  11. An Auto-management Thesis Program WebMIS Based on Workflow

    NASA Astrophysics Data System (ADS)

    Chang, Li; Jie, Shi; Weibo, Zhong

    An auto-management WebMIS based on workflow for bachelor thesis program is given in this paper. A module used for workflow dispatching is designed and realized using MySQL and J2EE according to the work principle of workflow engine. The module can automatively dispatch the workflow according to the date of system, login information and the work status of the user. The WebMIS changes the management from handwork to computer-work which not only standardizes the thesis program but also keeps the data and documents clean and consistent.

  12. Ultrathin strain-gated field effect transistor based on In-doped ZnO nanobelts

    NASA Astrophysics Data System (ADS)

    Zhang, Zheng; Du, Junli; Li, Bing; Zhang, Shuhao; Hong, Mengyu; Zhang, Xiaomei; Liao, Qingliang; Zhang, Yue

    2017-08-01

    In this work, we fabricated a strain-gated piezoelectric transistor based on single In-doped ZnO nanobelt with ±(0001) top/bottom polar surfaces. In the vertical structured transistor, the Pt tip of the AFM and Au film are used as source and drain electrode. The electrical transport performance of the transistor is gated by compressive strains. The working mechanism is attributed to the Schottky barrier height changed under the coupling effect of piezoresistive and piezoelectric. Uniquely, the transistor turns off under the compressive stress of 806 nN. The strain-gated transistor is likely to have important applications in high resolution mapping device and MEMS devices.

  13. Graphene-based flexible and stretchable thin film transistors.

    PubMed

    Yan, Chao; Cho, Jeong Ho; Ahn, Jong-Hyun

    2012-08-21

    Graphene has been attracting wide attention owing to its superb electronic, thermal and mechanical properties. These properties allow great applications in the next generation of optoelectronics, where flexibility and stretchability are essential. In this context, the recent development of graphene growth/transfer and its applications in field-effect transistors are involved. In particular, we provide a detailed review on the state-of-the-art of graphene-based flexible and stretchable thin film transistors. We address the principles of fabricating high-speed graphene analog transistors and the key issues of producing an array of graphene-based transistors on flexible and stretchable substrates. It provides a platform for future work to focus on understanding and realizing high-performance graphene-based transistors.

  14. Micro-power dissipation device described

    NASA Astrophysics Data System (ADS)

    Mao, X.; Zhou, L.; Zhou, J.

    1985-11-01

    The common-emitter current gain beta of a common two-pole transistor is generally below 250. They are referred to as high-beta or high gain transistors when the beta of such transistors exceeds 300. When the beta of a transistor is higher than 1,000, it is called a super-beta transistor (SBT) or supergain transistor. The micropower dissipation type has the widest applications among the high-beta. Micropower dissipation high-beta means that there is a high gain or a superhigh gain under a microcurrent. The device is widely used in small signal-detection systems and stereo audio equipment because of their characteristics of high gain, low frequency and low noise under small signals.

  15. Perception versus reality: elucidating motivation and expectations of current fellowship council minimally invasive surgery fellows.

    PubMed

    Watkins, Jeffrey R; Pryor, Aurora D; Truitt, Michael S; Jeyarajah, D Rohan

    2018-04-17

    The aim of our study is to determine minimally invasive trainee motivation and expectations for their respective fellowship. Minimally Invasive Surgery (MIS) is one of the largest non-ACGME post-residency training pathways though little is known concerning the process of residents choosing MIS as a fellowship focus. As general surgery evolves, it is important to understand resident motivation in order to better prepare them for a surgical career. A survey invitation was sent to current trainees in the Minimally Invasive and related pathways through the Fellowship Council. The participants were asked to complete a web-based questionnaire detailing demographics, experiences preparing for fellowship, motivation in choosing an MIS fellowship, and expectations for surgical practice after fellowship. Sixty-seven MIS trainees responded to the survey out of 151 invitations (44%). The Fellowship Council website, mentors, and other fellows were cited as the most helpful source of information when applying for fellowship. Trainees were active in surgical societies as residents, with 78% having membership in the ACS and 60% in SAGES. When deciding to pursue MIS as a fellowship, the desire to increase laparoscopic training was the most important factor. The least important reasons cited were lack of laparoendoscopic training in residency and desire to learn robotic surgery. The majority of trainees believed their laparoscopic skill set was above that of their residency cohort (81%). The most desired post-fellowship employment model is hospital employee (46%) followed by private practice (27%). Most fellows plan on marketing themselves as MIS surgeons (90%) or General Surgeons (78%) when in practice. Residents who choose MIS as a fellowship have a strong exposure to laparoscopy and want to become specialists in their field. Mentors and surgical societies including ACS and SAGES play a vital role in preparing residents for fellowship and practice.

  16. SST and terrestrial n-alkanes records in sediment of the Korean Plateau, East Sea (Japan Sea) during the last 400 kyr: Paleoceanographic and paleoclimatic implications

    NASA Astrophysics Data System (ADS)

    Hyun, Sangmin; Suh, Yean Jee; Kim, Jin Kyung

    2014-05-01

    SST variation was reconstructed using alkenones and their variation was compared with terrestrial n-alkanes signature from the sediment of the Korean Plateau, East Sea (Japan Sea) during the last 400 ka. SST variation showed glacial-interglacial time scale variation with a maximum temperature of 26 oC in MIS 7, and a minimum of 12 oC at MIS 2 and 6. The distribution of terrestrial n-alkanes signatures is characterized by the occurrence of high odd number predominance in most samples, however minor dominance of a specific compound (nC27 only) was the additional characteristic.bAverage Chain Length (ACL) and Carbon Preferences Index (ICP), derived from n-alkane distributions, showed a similar shifting between glacial-interglacial time-scale. This suggests that paleovegetation communities changed in response to paleoclimatological variations, and the input of terrestrial compound is strongly linked with paleoclimatology. In the previous work, isotopic composition of δ13C and δ15N of organic matter showed extreme temporal variation since MIS 11 suggesting influx of a large amount of terrestrial organic matters from the neighboring continent during MIS 2, 8 and 10. In particular, depleted values of δ13C during MIS 2, 8 and 10 were coincident with lower nitrogen isotope values indicating local paleoceanographic effects such as paleoproductivity changes. Decoupling of δ13C and δ15N during MIS 1, 3, 5, and 7, and coupling of the two during MIS 8 and 11 is observed, which can be interpreted as local productivity changes. The alkenones SST and n-alkanes signature coincided with carbon and nitrogen isotope variation in terms of glacial-interglacial time scale suggesting that the paleoenvironments in the East Sea is sensitive to the global climate changes associated with not only orbital-scale glacial-interglacial variations but also local paleceanographic variations.

  17. Minimally Invasive Direct Lateral Interbody Fusion (MIS-DLIF): Proof of Concept and Perioperative Results.

    PubMed

    Abbasi, Hamid; Abbasi, Ali

    2017-01-14

    Minimally invasive direct lateral interbody fusion (MIS-DLIF) is a novel approach for fusions of the lumbar spine. In this proof of concept study, we describe the surgical technique and report our experience and the perioperative outcomes of the first nine patients who underwent this procedure. In this study we establish the safety and efficacy of this approach. MIS-DLIF was performed on 15 spinal levels in nine patients who failed to respond to conservative therapy for the treatment of a re-herniated disk, spondylolisthesis, or other severe disk disease of the lumbar spine. We recorded surgery time, blood loss, fluoroscopy time, patient-reported pain, and complications. Throughout the MIS-DLIF procedure, the surgeon is aided by biplanar fluoroscopic imaging to place an interbody graft or cage into the disc space through the interpleural space. A discectomy is performed in the same minimally invasive fashion. The procedure is usually completed with posterior pedicle screw fixation. MIS-DLIF took 44/85 minutes, on average, for 1/2 levels, with 54/112 ml of blood loss, and 0.3/1.7 days of hospital stay. Four of nine patients did not require overnight hospitalization and were discharged two to four hours after surgery. We did not encounter any clinically significant complications. At more than ninety days post surgery, the patients reported a statistically significant reduction of 4.5 points on a 10-point sliding pain scale. MIS-DLIF with pedicle screw fixation is a safe and clinically effective procedure for fusions of the lumbar spine. The procedure overcomes many of the limitations of the current minimally invasive approaches to the lumbar spine and is technically straightforward. MIS-DLIF has the potential to improve patient outcomes and reduce costs relative to the current standard of care and therefore warrants further investigation. We are currently expanding this study to a larger cohort and documenting long-term outcome data.

  18. The effect of abrupt climate changes and climate background conditions in Southern Europe during the last glacial

    NASA Astrophysics Data System (ADS)

    Knorr, Gregor; Martin-Puertas, Celia; Brauer, Achim; Lohmann, Gerrit

    2015-04-01

    The last glacial period is characterized by abrupt and large temperature shifts in Greenland and the North Atlantic realm. Pollen and sediment data from Lago Grande di Monticchio (MON) have demonstrated a clear imprint of these fluctuations operating at millennial time-scales. Interestingly, basic mean environmental condition changes with respect to temperature and precipitation occurred during MIS4, separating warm and dry conditions during MIS5 from relatively cold and humid conditions within MIS3. This general climate background shift is superposed by distinct millennial-scale variability at MON. Using a fully coupled atmosphere-ocean general circulation model applying boundary conditions at 32 ka BP and pre-industrial conditions as a surrogate for MIS3 and MIS5, we have simulated and analysed characteristic changes in Southern Europe during the last glacial. We find that changes in the mean state at MON are mainly related to a partial shift of the North Atlantic deep water (NADW) convection sites from the Nordic Seas to South of Iceland, the presence of the Fennoscandian ice sheet and lower greenhouse gas concentrations. These background characteristics provide the basis for enhanced zonal moisture transport from the eastern North Atlantic to Middle and Southern Europe. Furthermore, simulations of abrupt climate change scenarios show that a deactivation of the convection sites South of Iceland during MIS3 leads to cooler and dryer conditions at MON. Such temperature and precipitation changes are thought to provide a counter-acting effect on woody vegetation and associated pollen signals at MON. This is in contrast to the impact of abrupt climate perturbation scenarios during MIS5, where no significant precipitation changes are detected. Hence, the simulated changes and underlying mechanisms are largely consistent with the recorded proxy evidence with respect to both, mean state and millennial-scale changes.

  19. Climatic variability during the penultimate interglacial (MIS 7) and glacial (MIS 6) periods recorded in a speleothem from Kanaan cave, Lebanon (Central Levant)

    NASA Astrophysics Data System (ADS)

    Nehme, Carole; Verheyden, Sophie; Breitenbach, Sebastian F. M.; Gillikin, David P.; Verheyden, Anouk; Cheng, Hai; Edwards, Laurence; Hellstrom, John; Noble, Stephen R.; Farrant, Andrew R.; Sahy, Diana; Goovaerts, Thomas; Salem, Ghada; Claeys, Philippe

    2017-04-01

    Little is known about terrestrial climate dynamics of the Levant during the penultimate interglacial-glacial period. A well-dated stalagmite ( 194 to 154 ka) from Kanaan cave, located near the Mediterranean in Lebanon, is examined for its petrography, growth history, and stable isotope geochemistry to answer the climate instability pattern of the glacial MIS 6 and possible wet phases. A highly resolved continental climate record from the northern Levant has been recovered from this precisely U-Th-dated speleothem, spanning the late penultimate interglacial (equivalent of the MIS 7) to the mid-penultimate glacial period ( MIS 6). The stalagmite grew slowly and discontinuously with an unstable isotopic pattern from 194 and at least up to 178 ka. Subsequently, the stalagmite ceased growing from 169.5 to 163.1 ka (interpolated ages) with a hiatus of ca. 6.24 ka according to the model age. However, low δ 18O and δ 13C values indicate generally cold, but overall more humid climate compared to the last glacial (MIS 3). Higher growth rates during the mid-penultimate glacial period ( 163-154 ka) are most probably linked to increased water recharge in the vadose zone. A short More distinct layering in the upper section compared to the basal part of the stalagmite suggests stronger seasonality from 163 ka to 154 ka. Negative oxygen and carbon isotope excursions were found at ˜155.5 ka, ˜156 ka, between ˜159.6 and ˜160.1 ka and at ˜162.6 ka. The inferred Kanaan cave humid intervals during the mid-penultimate period follow variations of pollen records in the Eastern and Western Mediterranean basins and correlate well with the synthetic Greenland records and East Asian Summer Monsoon Interstadials, indicating short warm/wet periods similar to the D-O events during MIS 4-3 in the Eastern Mediterranean region.

  20. High-frequency noise characterization of graphene field effect transistors on SiC substrates

    NASA Astrophysics Data System (ADS)

    Yu, C.; He, Z. Z.; Song, X. B.; Liu, Q. B.; Dun, S. B.; Han, T. T.; Wang, J. J.; Zhou, C. J.; Guo, J. C.; Lv, Y. J.; Cai, S. J.; Feng, Z. H.

    2017-07-01

    Considering its high carrier mobility and high saturation velocity, a low-noise amplifier is thought of as being the most attractive analogue application of graphene field-effect transistors. The noise performance of graphene field-effect transistors at frequencies in the K-band remains unknown. In this work, the noise parameters of a graphene transistor are measured from 10 to 26 GHz and noise models are built with the data. The extrinsic minimum noise figure for a graphene transistor reached 1.5 dB, and the intrinsic minimum noise figure was as low as 0.8 dB at a frequency of 10 GHz, which were comparable with the results from tests on Si CMOS and started to approach those for GaAs and InP transistors. Considering the short development time, the current results are a significant step forward for graphene transistors and show their application potential in high-frequency electronics.

  1. Electrical coupling of single cardiac rat myocytes to field-effect and bipolar transistors.

    PubMed

    Kind, Thomas; Issing, Matthias; Arnold, Rüdiger; Müller, Bernt

    2002-12-01

    A novel bipolar transistor for extracellular recording the electrical activity of biological cells is presented, and the electrical behavior compared with the field-effect transistor (FET). Electrical coupling is examined between single cells separated from the heart of adults rats (cardiac myocytes) and both types of transistors. To initiate a local extracellular voltage, the cells are periodically stimulated by a patch pipette in voltage clamp and current clamp mode. The local extracellular voltage is measured by the planar integrated electronic sensors: the bipolar and the FET. The small signal transistor currents correspond to the local extracellular voltage. The two types of sensor transistors used here were developed and manufactured in the laboratory of our institute. The manufacturing process and the interfaces between myocytes and transistors are described. The recordings are interpreted by way of simulation based on the point-contact model and the single cardiac myocyte model.

  2. Pseudo 2-transistor active pixel sensor using an n-well/gate-tied p-channel metal oxide semiconductor field eeffect transistor-type photodetector with built-in transfer gate

    NASA Astrophysics Data System (ADS)

    Seo, Sang-Ho; Seo, Min-Woong; Kong, Jae-Sung; Shin, Jang-Kyoo; Choi, Pyung

    2008-11-01

    In this paper, a pseudo 2-transistor active pixel sensor (APS) has been designed and fabricated by using an n-well/gate-tied p-channel metal oxide semiconductor field effect transistor (PMOSFET)-type photodetector with built-in transfer gate. The proposed sensor has been fabricated using a 0.35 μm 2-poly 4-metal standard complementary metal oxide semiconductor (CMOS) logic process. The pseudo 2-transistor APS consists of two NMOSFETs and one photodetector which can amplify the generated photocurrent. The area of the pseudo 2-transistor APS is 7.1 × 6.2 μm2. The sensitivity of the proposed pixel is 49 lux/(V·s). By using this pixel, a smaller pixel area and a higher level of sensitivity can be realized when compared with a conventional 3-transistor APS which uses a pn junction photodiode.

  3. Ultra-high gain diffusion-driven organic transistor.

    PubMed

    Torricelli, Fabrizio; Colalongo, Luigi; Raiteri, Daniele; Kovács-Vajna, Zsolt Miklós; Cantatore, Eugenio

    2016-02-01

    Emerging large-area technologies based on organic transistors are enabling the fabrication of low-cost flexible circuits, smart sensors and biomedical devices. High-gain transistors are essential for the development of large-scale circuit integration, high-sensitivity sensors and signal amplification in sensing systems. Unfortunately, organic field-effect transistors show limited gain, usually of the order of tens, because of the large contact resistance and channel-length modulation. Here we show a new organic field-effect transistor architecture with a gain larger than 700. This is the highest gain ever reported for organic field-effect transistors. In the proposed organic field-effect transistor, the charge injection and extraction at the metal-semiconductor contacts are driven by the charge diffusion. The ideal conditions of ohmic contacts with negligible contact resistance and flat current saturation are demonstrated. The approach is general and can be extended to any thin-film technology opening unprecedented opportunities for the development of high-performance flexible electronics.

  4. Ultra-high gain diffusion-driven organic transistor

    NASA Astrophysics Data System (ADS)

    Torricelli, Fabrizio; Colalongo, Luigi; Raiteri, Daniele; Kovács-Vajna, Zsolt Miklós; Cantatore, Eugenio

    2016-02-01

    Emerging large-area technologies based on organic transistors are enabling the fabrication of low-cost flexible circuits, smart sensors and biomedical devices. High-gain transistors are essential for the development of large-scale circuit integration, high-sensitivity sensors and signal amplification in sensing systems. Unfortunately, organic field-effect transistors show limited gain, usually of the order of tens, because of the large contact resistance and channel-length modulation. Here we show a new organic field-effect transistor architecture with a gain larger than 700. This is the highest gain ever reported for organic field-effect transistors. In the proposed organic field-effect transistor, the charge injection and extraction at the metal-semiconductor contacts are driven by the charge diffusion. The ideal conditions of ohmic contacts with negligible contact resistance and flat current saturation are demonstrated. The approach is general and can be extended to any thin-film technology opening unprecedented opportunities for the development of high-performance flexible electronics.

  5. Proton Damage Effects on Carbon Nanotube Field-Effect Transistors

    DTIC Science & Technology

    2014-06-19

    PROTON DAMAGE EFFECTS ON CARBON NANOTUBE FIELD-EFFECT TRANSISTORS THESIS Evan R. Kemp, Ctr...United States. AFIT-ENP-T-14-J-39 PROTON DAMAGE EFFECTS ON CARBON NANOTUBE FIELD-EFFECT TRANSISTORS THESIS Presented to...PROTON DAMAGE EFFECTS ON CARBON NANOTUBE FIELD-EFFECT TRANSISTORS Evan R. Kemp, BS Ctr, USAF Approved: // Signed

  6. Evaluation of semiconductor devices for Electric and Hybrid Vehicle (EHV) ac-drive applications, volume 2

    NASA Technical Reports Server (NTRS)

    Lee, F. C.; Chen, D. Y.; Jovanic, M.; Hopkins, D. C.

    1985-01-01

    Test data of switching times characterization of bipolar transistors, of field effect transistor's switching times on-resistance and characterization, comparative data of field effect transistors, and test data of field effect transistor's parallel operation characterization are given. Data is given in the form of graphs.

  7. Improved insulator layer for MIS devices

    NASA Technical Reports Server (NTRS)

    Miller, W. E.

    1980-01-01

    Insulating layer of supersonic conductor such as LaF sub 3 has been shown able to impart improved electrical properties to photoconductive detectors and promises to improve other metal/insulator/semiconductor (MIS) devices, e.g., MOSFET and integrated circuits.

  8. A steep-slope transistor based on abrupt electronic phase transition

    NASA Astrophysics Data System (ADS)

    Shukla, Nikhil; Thathachary, Arun V.; Agrawal, Ashish; Paik, Hanjong; Aziz, Ahmedullah; Schlom, Darrell G.; Gupta, Sumeet Kumar; Engel-Herbert, Roman; Datta, Suman

    2015-08-01

    Collective interactions in functional materials can enable novel macroscopic properties like insulator-to-metal transitions. While implementing such materials into field-effect-transistor technology can potentially augment current state-of-the-art devices by providing unique routes to overcome their conventional limits, attempts to harness the insulator-to-metal transition for high-performance transistors have experienced little success. Here, we demonstrate a pathway for harnessing the abrupt resistivity transformation across the insulator-to-metal transition in vanadium dioxide (VO2), to design a hybrid-phase-transition field-effect transistor that exhibits gate controlled steep (`sub-kT/q') and reversible switching at room temperature. The transistor design, wherein VO2 is implemented in series with the field-effect transistor's source rather than into the channel, exploits negative differential resistance induced across the VO2 to create an internal amplifier that facilitates enhanced performance over a conventional field-effect transistor. Our approach enables low-voltage complementary n-type and p-type transistor operation as demonstrated here, and is applicable to other insulator-to-metal transition materials, offering tantalizing possibilities for energy-efficient logic and memory applications.

  9. A steep-slope transistor based on abrupt electronic phase transition.

    PubMed

    Shukla, Nikhil; Thathachary, Arun V; Agrawal, Ashish; Paik, Hanjong; Aziz, Ahmedullah; Schlom, Darrell G; Gupta, Sumeet Kumar; Engel-Herbert, Roman; Datta, Suman

    2015-08-07

    Collective interactions in functional materials can enable novel macroscopic properties like insulator-to-metal transitions. While implementing such materials into field-effect-transistor technology can potentially augment current state-of-the-art devices by providing unique routes to overcome their conventional limits, attempts to harness the insulator-to-metal transition for high-performance transistors have experienced little success. Here, we demonstrate a pathway for harnessing the abrupt resistivity transformation across the insulator-to-metal transition in vanadium dioxide (VO2), to design a hybrid-phase-transition field-effect transistor that exhibits gate controlled steep ('sub-kT/q') and reversible switching at room temperature. The transistor design, wherein VO2 is implemented in series with the field-effect transistor's source rather than into the channel, exploits negative differential resistance induced across the VO2 to create an internal amplifier that facilitates enhanced performance over a conventional field-effect transistor. Our approach enables low-voltage complementary n-type and p-type transistor operation as demonstrated here, and is applicable to other insulator-to-metal transition materials, offering tantalizing possibilities for energy-efficient logic and memory applications.

  10. Enhanced transconductance in a double-gate graphene field-effect transistor

    NASA Astrophysics Data System (ADS)

    Hwang, Byeong-Woon; Yeom, Hye-In; Kim, Daewon; Kim, Choong-Ki; Lee, Dongil; Choi, Yang-Kyu

    2018-03-01

    Multi-gate transistors, such as double-gate, tri-gate and gate-all-around transistors are the most advanced Si transistor structure today. Here, a genuine double-gate transistor with a graphene channel is experimentally demonstrated. The top and bottom gates of the double-gate graphene field-effect transistor (DG GFET) are electrically connected so that the conductivity of the graphene channel can be modulated simultaneously by both the top and bottom gate. A single-gate graphene field-effect transistor (SG GFET) with only the top gate is also fabricated as a control device. For systematical analysis, the transfer characteristics of both GFETs were measured and compared. Whereas the maximum transconductance of the SG GFET was 17.1 μS/μm, that of the DG GFET was 25.7 μS/μm, which is approximately a 50% enhancement. The enhancement of the transconductance was reproduced and comprehensively explained by a physics-based compact model for GFETs. The investigation of the enhanced transfer characteristics of the DG GFET in this work shows the possibility of a multi-gate architecture for high-performance graphene transistor technology.

  11. Genetic therapies for RNA mis-splicing diseases.

    PubMed

    Hammond, Suzan M; Wood, Matthew J A

    2011-05-01

    RNA mis-splicing diseases account for up to 15% of all inherited diseases, ranging from neurological to myogenic and metabolic disorders. With greatly increased genomic sequencing being performed for individual patients, the number of known mutations affecting splicing has risen to 50-60% of all disease-causing mutations. During the past 10years, genetic therapy directed toward correction of RNA mis-splicing in disease has progressed from theoretical work in cultured cells to promising clinical trials. In this review, we discuss the use of antisense oligonucleotides to modify splicing as well as the principles and latest work in bifunctional RNA, trans-splicing and modification of U1 and U7 snRNA to target splice sites. The success of clinical trials for modifying splicing to treat Duchenne muscular dystrophy opens the door for the use of splicing modification for most of the mis-splicing diseases. Copyright © 2011 Elsevier Ltd. All rights reserved.

  12. Minimal invasive surgery in the newborn: current status and evidence.

    PubMed

    Lacher, Martin; Kuebler, Joachim F; Dingemann, Jens; Ure, Benno M

    2014-10-01

    The evolution of minimally invasive surgery (MIS) in the newborn has been delayed due to the limited working space and the unique physiology. With the development of smaller instruments and advanced surgical skills, many of the initial obstacles have been overcome. MIS is currently used in specialized centers around the world with excellent feasibility. Obvious advantages include better cosmesis, less trauma, and better postoperative musculoskeletal function, in particular after thoracic procedures. However, the aim of academic studies has shifted from proving feasibility to a critical evaluation of outcome. Prospective randomized trials and high-level evidence for the benefit of endoscopic surgery are still scarce. Questions to be answered in the upcoming years will therefore include both advantages and potential disadvantages of MIS, especially in neonates. This review summarizes recent developments of MIS in neonates and the evidence for its use. Copyright © 2014 Elsevier Inc. All rights reserved.

  13. Radiation effects in LDD MOS devices

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Woodruff, R.L.; Adams, J.R.

    1987-12-01

    The purpose of this work is to investigate the response of lightly doped drain (LDD) n-channel transistors to ionizing radiation. Transistors were fabricated with conventional (non-LDD) and lightly doped drain (LDD) structures using both standard (non-hardened) and radiation hardened gate oxides. Characterization of the transistors began with a correlation of the total-dose effects due to 10 keV x-rays with Co-60 gamma rays. The authors find that for the gate oxides and transistor structures investigated in this work, 10 keV x-rays produce more fixed-charge guild-up in the gate oxide, and more interface charge than do Co-60 gamma rays. They determined thatmore » the radiation response of LDD transistors is similar to that of conventional (non-LDD) transistors. In addition, both standard and radiation-hardened transistors subjected to hot carrier stress before irradiation show a similar radiation response. After exposure to 1.0 x 10/sup 6/ rads(Si), non-hardened transistors show increased susceptibility to hot-carrier graduation, while the radiation-hardened transistors exhibit similar hot-carrier degradation to non-irradiated devices. The authors have demonstrated a fully-integrated radiation hardened process tht is solid to 1.0 x 10/sup 6/ rads(Si), and shows promise for achieving 1.0 x 10/sup 7/ rad(Si) total-dose capability.« less

  14. Feasibility Study of Extended-Gate-Type Silicon Nanowire Field-Effect Transistors for Neural Recording

    PubMed Central

    Kang, Hongki; Kim, Jee-Yeon; Choi, Yang-Kyu; Nam, Yoonkey

    2017-01-01

    In this research, a high performance silicon nanowire field-effect transistor (transconductance as high as 34 µS and sensitivity as 84 nS/mV) is extensively studied and directly compared with planar passive microelectrode arrays for neural recording application. Electrical and electrochemical characteristics are carefully characterized in a very well-controlled manner. We especially focused on the signal amplification capability and intrinsic noise of the transistors. A neural recording system using both silicon nanowire field-effect transistor-based active-type microelectrode array and platinum black microelectrode-based passive-type microelectrode array are implemented and compared. An artificial neural spike signal is supplied as input to both arrays through a buffer solution and recorded simultaneously. Recorded signal intensity by the silicon nanowire transistor was precisely determined by an electrical characteristic of the transistor, transconductance. Signal-to-noise ratio was found to be strongly dependent upon the intrinsic 1/f noise of the silicon nanowire transistor. We found how signal strength is determined and how intrinsic noise of the transistor determines signal-to-noise ratio of the recorded neural signals. This study provides in-depth understanding of the overall neural recording mechanism using silicon nanowire transistors and solid design guideline for further improvement and development. PMID:28350370

  15. Feasibility Study of Extended-Gate-Type Silicon Nanowire Field-Effect Transistors for Neural Recording.

    PubMed

    Kang, Hongki; Kim, Jee-Yeon; Choi, Yang-Kyu; Nam, Yoonkey

    2017-03-28

    In this research, a high performance silicon nanowire field-effect transistor (transconductance as high as 34 µS and sensitivity as 84 nS/mV) is extensively studied and directly compared with planar passive microelectrode arrays for neural recording application. Electrical and electrochemical characteristics are carefully characterized in a very well-controlled manner. We especially focused on the signal amplification capability and intrinsic noise of the transistors. A neural recording system using both silicon nanowire field-effect transistor-based active-type microelectrode array and platinum black microelectrode-based passive-type microelectrode array are implemented and compared. An artificial neural spike signal is supplied as input to both arrays through a buffer solution and recorded simultaneously. Recorded signal intensity by the silicon nanowire transistor was precisely determined by an electrical characteristic of the transistor, transconductance. Signal-to-noise ratio was found to be strongly dependent upon the intrinsic 1/f noise of the silicon nanowire transistor. We found how signal strength is determined and how intrinsic noise of the transistor determines signal-to-noise ratio of the recorded neural signals. This study provides in-depth understanding of the overall neural recording mechanism using silicon nanowire transistors and solid design guideline for further improvement and development.

  16. Copper atomic-scale transistors.

    PubMed

    Xie, Fangqing; Kavalenka, Maryna N; Röger, Moritz; Albrecht, Daniel; Hölscher, Hendrik; Leuthold, Jürgen; Schimmel, Thomas

    2017-01-01

    We investigated copper as a working material for metallic atomic-scale transistors and confirmed that copper atomic-scale transistors can be fabricated and operated electrochemically in a copper electrolyte (CuSO 4 + H 2 SO 4 ) in bi-distilled water under ambient conditions with three microelectrodes (source, drain and gate). The electrochemical switching-on potential of the atomic-scale transistor is below 350 mV, and the switching-off potential is between 0 and -170 mV. The switching-on current is above 1 μA, which is compatible with semiconductor transistor devices. Both sign and amplitude of the voltage applied across the source and drain electrodes ( U bias ) influence the switching rate of the transistor and the copper deposition on the electrodes, and correspondingly shift the electrochemical operation potential. The copper atomic-scale transistors can be switched using a function generator without a computer-controlled feedback switching mechanism. The copper atomic-scale transistors, with only one or two atoms at the narrowest constriction, were realized to switch between 0 and 1 G 0 ( G 0 = 2e 2 /h; with e being the electron charge, and h being Planck's constant) or 2 G 0 by the function generator. The switching rate can reach up to 10 Hz. The copper atomic-scale transistor demonstrates volatile/non-volatile dual functionalities. Such an optimal merging of the logic with memory may open a perspective for processor-in-memory and logic-in-memory architectures, using copper as an alternative working material besides silver for fully metallic atomic-scale transistors.

  17. Scalable fabrication of self-aligned graphene transistors and circuits on glass.

    PubMed

    Liao, Lei; Bai, Jingwei; Cheng, Rui; Zhou, Hailong; Liu, Lixin; Liu, Yuan; Huang, Yu; Duan, Xiangfeng

    2012-06-13

    Graphene transistors are of considerable interest for radio frequency (rf) applications. High-frequency graphene transistors with the intrinsic cutoff frequency up to 300 GHz have been demonstrated. However, the graphene transistors reported to date only exhibit a limited extrinsic cutoff frequency up to about 10 GHz, and functional graphene circuits demonstrated so far can merely operate in the tens of megahertz regime, far from the potential the graphene transistors could offer. Here we report a scalable approach to fabricate self-aligned graphene transistors with the extrinsic cutoff frequency exceeding 50 GHz and graphene circuits that can operate in the 1-10 GHz regime. The devices are fabricated on a glass substrate through a self-aligned process by using chemical vapor deposition (CVD) grown graphene and a dielectrophoretic assembled nanowire gate array. The self-aligned process allows the achievement of unprecedented performance in CVD graphene transistors with a highest transconductance of 0.36 mS/μm. The use of an insulating substrate minimizes the parasitic capacitance and has therefore enabled graphene transistors with a record-high extrinsic cutoff frequency (> 50 GHz) achieved to date. The excellent extrinsic cutoff frequency readily allows configuring the graphene transistors into frequency doubling or mixing circuits functioning in the 1-10 GHz regime, a significant advancement over previous reports (∼20 MHz). The studies open a pathway to scalable fabrication of high-speed graphene transistors and functional circuits and represent a significant step forward to graphene based radio frequency devices.

  18. Paleopedological research of the dynamics alteration in environment of the Lover Volga region in the last macrocycle

    NASA Astrophysics Data System (ADS)

    Bagrova, Svetlana; Makeev, Alexander; Rusakov, Alexey; Yanina, Tatiana; Kurbanov, Redzhep

    2017-04-01

    Caspian Sea reflects in its development global climate changes, glacial-interglacial rhythms in Russian plains and mountain areas. It is stratigraphic region for drawing up a single stratigraphic and paleogeographic plan of the Upper Pleistocene of Northern Eurasia. To date, accumulated a considerable amount of material on the Quaternary history of Ponto-Caspian, based on stratigraphic, paleogeographic and geomorphological studies. However, paleopedological work in the region have been starting for the first time. Studying paleopedology in soil-sediment thickness have paramount importance, as they can reliably break down the steps of the surface on which stabilization was carried out paedogenesis with further sedimentation, and allow us to trace the stages of evolution of the environment of the region. The site (Srednyaya Akhtuba) located on the left bank of the Akhtuba River, 20 km from the Volzhsky city, the upper part of Lower Volga region. This marine terrace represented by 6 paedogenetic levels, including 7 soils (MIS1-MIS5) (Yanina, 2014) separated by sediments (precipitation) of different structure and genesis. The upper part of the section (0-150 cm) presented by a typical for the dry steppe area soil Kastanzem (WRB, 2014) (MIS1). Parent rock material is a great pack (>1m) of the Caspian marine sediments, represented by a series of layers of chocolate clays (MIS2) with interbedding of sands. Lower, is a pack (520-670 cm), formed during Atelian regression of the Caspian Sea (MIS3-MIS4), presented by one well-developed soil with truncated humus horizon and two loessic layers with signs of soil formation (rhizolithes, manganese nodule, cryogenesis structure and etc) MIS3 stage. The lower part of Atel-Ahtuba strata (910-1530 cm) is presented by carbonate loess without noticeable pedogenetic transformation. From a depth of 1530 cm begins thick layer of loess-soil series, presented by MIS5a-e Mezin pedocomplex, dedicated to the Late Khazar-Girkan transgression, with three well-preserved soils. The upper soil, Gleyic Phaeozem, has accretionary humus horizon (about 1 m), many krotovinas, and network of frost wedges 40-50 cm. Wedges start in the overlying Atel-Akhtuba loess layer indicating the beginning of the last glacial cycle (MIS4). The middle soil, Gleyic Chernozem, has first 5 cm humus horizon intermixed with Bg horizon of the upper soil (welded paleosol). Until the middle of the profile (1740 cm) are the end of the loess permafrost wedges. Gleyic features are due to seasonal overflooding. The lower soil of Mezin pedocomplex (MIS5e), Mollic Calcic Gleysol, formed in loess sediments accumulated during penultimate glaciation (MIS6) and has reworked upper boundary (10-13 cm), well-defined humus horizon with gley process. Three soils of Mezin pedocomplex have common features: semi terrestrial genesis with gleyic features due to long-term seasonal overflooding; well developed humus horizons and complex assemblage of carbonate neoformations, formed under steppe environment. Pedogenetic horizons serve as good stratigraphic markers that will help to correlate late Pleistocene soil-sedimentary sequences of the whole Caspian-Azov-Black sea region, East European Plain and link it with global stratigraphic schemes. Detailed analytical and further field studies are required to reveal further pedogenetic response to environmental changes in the area. Research was supported by Russian Science Foundation, project 14-17-00705

  19. Response of diatom and silicoflagellate assemblages in the central Gulf of California to regional climate change during the past 55 kyrs

    USGS Publications Warehouse

    Barron, John A.; Bukry, David; Cheshire, Heather

    2014-01-01

    High-resolution studies of diatoms and silicoflagellates of the past 55 kyrs in cores MD02-2517/2515 from the central Gulf of California (GoC) reveal profound changes in GoC surface waters. Roperia tesselata, a diatom proxy for late winter–early spring upwelling, and Dictyocha stapedia, a subtropical silicoflagellate indicative of GoC sea surface temperatures (SSTs) > 24 °C, are common during the Holocene but rare during Marine Isotope Stage (MIS) 2 and most of MIS 3, a relationship that likely reflects a more northerly position of the North Pacific High (NPH) during the Holocene. In contrast during most of MIS 2 (~ 27–15 ka), the persistent presence of Distephanus speculum, a silicoflagellate associated with SSTs During MIS 3 (~ 55–27 ka), increased dominance of Azpeitia nodulifera (diatom) implies that stratified, tropical waters were present year round, whereas silicoflagellate assemblages suggest that stratified tropical conditions alternated with more productive, upwelling conditions on millennial timescales. Reduced biosiliceous productivity during Heinrich events likely reflected a reduction in both surface water nutrient levels and in the strength of northwest winds due to a weakened and more southerly NPH. Conversely, enhanced biosiliceous productivity during MIS 3 interstadials was probably linked to heightened nutrient levels and a strengthened NPH. Abrupt relative abundance increases of the silicoflagellate, Dictyocha aculeata, approximate the termination of MIS3 Heinrich events and may signal times when nutrient-rich deep waters associated with the resumption of enhanced Atlantic Meridional Overturning Circulation penetrated into the central Gulf.

  20. Palaeoclimatic implications of aeolian sediments on the Miaodao Islands, Bohai Sea, East China, based on OSL dating and proxies

    NASA Astrophysics Data System (ADS)

    Xu, Shujian; Ding, Xinchao; Yu, Lupeng; Ni, Zhichao

    2015-12-01

    The loess-paleosol sequences in Shandong Province, East China, is an important aeolian archive, which can provide information for aeolian activity, palaeoclimatic change and sea level change in eastern coast of China since the last interglacial period. However, for so long, most of the studies about loess have been focused on the Chinese Loess Plateau, remaining many questions and disputes about the loess in East China. The Xianjingyuan (XJY) section on the TIA, Bohai Sea, is a representative aeolian section for islands off the eastern coast of China. In this study, optically stimulated luminescence (OSL) dating, particle size and magnetic susceptibility were applied to date and analysis the loess-paleosol sequences in this section. The results show that: (1) The OSL ages at the depths of 0.8 m, 2.5 m, and 3.9 m are 12.6 ± 1.0 ka, 19.2 ± 1.1 ka and 56.9 ± 2.6 ka, respectively, and the loess started to accumulate at ca. 86.5 ka according to the depositional rates (2) The loess accumulated mainly during the Marine Isotope Stage (MIS) 2, i.e., Last glacial maximum and deglaciation, MIS4 and MIS3b with higher depositional rate, coarser grain size, and higher magnetic susceptibility; while paleosol mainly developed during MIS3a, MIS3c and MIS5 with lower depositional rate, finer grain size and lower magnetic susceptibility. (3) The palaeoclimatic changes and aeolian sediments evolution were mainly controlled by the changes of East Asian summer monsoon and sea levels.

  1. Safety of robotic prostatectomy over time: a national study of in-hospital injury.

    PubMed

    Chughtai, Bilal; Isaacs, Abby J; Mao, Jialin; Lee, Richard; Te, Alexis; Kaplan, Steven; Sedrakyan, Art

    2015-02-01

    To assess national trends of iatrogenic complications and associated burden of care among patients undergoing open and minimally invasive prostatectomy using a population-based cohort. Using the nationally representative cohort, we identified patients who were diagnosed with prostate cancer, and underwent prostatectomy during 2001 and 2011. We determined the risk of iatrogenic complication and length of stay (LOS) over time among open and minimally invasive surgery (MIS) patients. Hierarchical multivariable logistic regression was performed to assess the changes over time and elucidate independent predictors of iatrogenic complications. We identified 556,932 and 219,434 prostate cancer patients undergoing open and minimally invasive prostatectomy. We found that iatrogenic complications for MIS were less frequent in later years (years 09-11 vs. year 01-02 odds ratio (OR), 0.21; 95% confidence intervals (CI), 0.09-0.40). MIS was associated with higher risk of iatrogenic complications in early period (years 01-02 OR, 3.81; 95% CI, 1.72-8.41), but lower risk in late period (years 09-11 OR 0.72 95% CI 0.61-0.86). Patients who experienced iatrogenic complications tended to have longer LOS (Median: Open vs. MIS, 4 days vs. 3 day) than those who didn't (Median: Open vs. MIS, 2 days vs. 1 day), regardless of procedure type. We found that minimally invasive prostatectomy is associated with lower risk of iatrogenic complications when compared with open surgery (OS). However, as "learning curve" is overcome over time, MIS becomes safer than OS. Iatrogenic complications are not benign and seem to be associated with higher burden of inpatient care.

  2. How do geometry-related parameters influence the clinical performance of orthodontic mini-implants? A systematic review and meta-analysis.

    PubMed

    Cunha, A C; da Veiga, A M A; Masterson, D; Mattos, C T; Nojima, L I; Nojima, M C G; Maia, L C

    2017-12-01

    The aim of this systematic review and meta-analysis was to investigate how parameters related to geometry influence the clinical performance of orthodontic mini-implants (MIs). Systematic searches were performed in electronic databases including MEDLINE, Scopus, Web of Science, Virtual Health Library, and Cochrane Library and reference lists up to March 2016. Eligibility criteria comprised clinical studies involving patients who received MIs for orthodontic anchorage, with data for categories of MI dimension, shape, and thread design and insertion site, and evaluated by assessment of primary and secondary stability. Study selection, data extraction, quality assessment, and a meta-analysis were carried out. Twenty-seven studies were included in the qualitative synthesis: five randomized, eight prospective, and 14 retrospective clinical studies. One study with a serious risk of bias was later excluded. Medium and short MIs (1.4-1.9mm diameter and 5-8mm length) presented the highest success rates (0.87, 95% CI 0.80-0.92). A maximum insertion torque of 13.28Ncm (standard error 0.34) was observed for tapered self-drilling MIs in the mandible, whereas cylindrical MIs in the maxilla presented a maximum removal torque of 10.01Ncm (standard error 0.17). Moderate evidence indicates that the clinical performance of MIs is influenced by implant geometry parameters and is also related to properties of the insertion site. However, further research is necessary to support these associations. Copyright © 2017 International Association of Oral and Maxillofacial Surgeons. Published by Elsevier Ltd. All rights reserved.

  3. Cross-cultural adaptation to Portuguese of tools for assessing the nutritional status of patients on dialysis.

    PubMed

    Fetter, Renata Lemos; Bigogno, Fernanda Guedes; de Oliveira, Fernanda Galvão Pasculli; Avesani, Carla Maria

    2014-01-01

    The 7 point subjective global assessment (7p-SGA) and the malnutrition inflammation score (MIS) are tools commonly applied for the assessment of nutritional status in dialyzed patients. Both were developed in English and require translation to Portuguese to be applied in Brazil. The cross-cultural equivalence process ensures semantic and measurement equivalence of a translated tool. To perform the cross-cultural adaptation to Portuguese of the 7p-SGA and MIS. Semantic equivalence was performed by the back-translation method and by assessing the degree of similarity between the original instrument and that back-translated from Portuguese to English (Back-translation). The assessment of the equivalence measurement was made by evaluating the intern reliability (Cronbach's α) and interobserver reliability (two observers). One-hundred and one elderly patients on hemodialysis (HD) were included. Both instruments showed a high degree of semantic similarity with results close to the maximum value (7p-SGA 96.8 ± 7.8 and MIS 99.6 ± 1.4). The intern consistency showed a Cronbach's α value for 7p-SGA of 0.72 and of 0.53 for MIS. The interobserver reproducibility of 7p-SGA was moderate (intraclass coefficient [ICC] = 0.74 [95% CI: 0.58; 0.84]), while for MIS was strong (ICC = 0.88 [95% CI: 0.81; 0.93]). The 7p-SGA and MIS translated into Portuguese can be applied for assessing the nutritional status of elderly patients on HD. Studies testing the applicability of these instruments in adult patients on HD and in peritoneal dialysis should yet be performed.

  4. Pharyngeal mis-sequencing in dysphagia: characteristics, rehabilitative response, and etiological speculation.

    PubMed

    Huckabee, Maggie-Lee; Lamvik, Kristin; Jones, Richard

    2014-08-15

    Clinical data are submitted as documentation of a pathophysiologic feature of dysphagia termed pharyngeal mis-sequencing and to encourage clinicians and researchers to adopt more critical approaches to diagnosis and treatment planning. Recent clinical experience has identified a cohort of patients who present with an atypical dysphagia not specifically described in the literature: mis-sequenced constriction of the pharynx when swallowing. As a result, they are unable to coordinate streamlined bolus transfer from the pharynx into the esophagus. This mis-sequencing contributes to nasal redirection, aspiration, and, for some, the inability to safely tolerate an oral diet. Sixteen patients (8 females, 8 males), with a mean age of 44 years (range=25-78), had an average time post-onset of 23 months (range=2-72) at initiation of intensive rehabilitation. A 3-channel manometric catheter was used to measure pharyngeal pressure. The average peak-to-peak latency between nadir pressures at sensor-1 and sensor-2 was 15 ms (95% CI, -2 to 33 ms), compared to normative mean latency of 239 ms (95% CI, 215 to 263 ms). Rehabilitative responses are summarized, along with a single detailed case report. It is unclear from these data if pharyngeal mis-sequencing is (i) a pathological feature of impaired motor planning from brainstem damage or (ii) a maladaptive compensation developed in response to chronic dysphagia. Future investigation is needed to provide a full report of pharyngeal mis-sequencing, and the implications on our understanding of underlying neural control of swallowing. Copyright © 2014 Elsevier B.V. All rights reserved.

  5. Substrate potential of last interglacial to Holocene permafrost organic matter for future microbial greenhouse gas production

    NASA Astrophysics Data System (ADS)

    Stapel, Janina G.; Schwamborn, Georg; Schirrmeister, Lutz; Horsfield, Brian; Mangelsdorf, Kai

    2018-04-01

    In this study the organic matter (OM) in several permafrost cores from Bol'shoy Lyakhovsky Island in NE Siberia was investigated. In the context of the observed global warming the aim was to evaluate the potential of freeze-locked OM from different depositional ages to act as a substrate provider for microbial production of greenhouse gases from thawing permafrost. To assess this potential, the concentrations of free and bound acetate, which form an appropriate substrate for methanogenesis, were determined. The largest free-acetate (in pore water) and bound-acetate (organic-matrix-linked) substrate pools were present in interstadial marine isotope stage (MIS) 3 and stadial MIS 4 Yedoma permafrost deposits. In contrast, deposits from the last interglacial MIS 5e (Eemian) contained only a small pool of substrates. The Holocene (MIS 1) deposits revealed a significant bound-acetate pool, representing a future substrate potential upon release during OM degradation. Additionally, pyrolysis experiments on the OM allocated an increased aliphatic character to the MIS 3 and 4 Late Pleistocene deposits, which might indicate less decomposed and presumably more easily degradable OM. Biomarkers for past microbial communities, including those for methanogenic archaea, also showed the highest abundance during MIS 3 and 4, which indicated OM-stimulated microbial degradation and presumably greenhouse gas production during time of deposition. On a broader perspective, Arctic warming will increase and deepen permafrost thaw and favor substrate availability from older freeze-locked permafrost deposits. Thus, the Yedoma deposits especially showed a high potential for providing substrates relevant for microbial greenhouse gas production.

  6. Environmental Impact of Minimally Invasive Surgery in the United States: An Estimate of the Carbon Dioxide Footprint

    PubMed Central

    Power, Nicholas E.; Silberstein, Jonathan L.; Ghoneim, Tarek P.; Guillonneau, Bertrand

    2012-01-01

    Abstract Purpose To attempt to quantitate the carbon footprint of minimally invasive surgery (MIS) through approximated scope 1 to 3 CO2 emissions to identify its potential role in global warming. Patients and Methods To estimate national usage, we determined the number of inpatient and outpatient MIS procedures using International Classification of Diseases, ninth revision-clinical modification codes for all MIS procedures in a 2009 sample collected in national databases. Need for surgery was considered essential, and therefore traditional open surgery was used as the comparator. Scope 1 (direct) CO2 emissions resulting from CO2 gas used for insufflation were based on both escaping procedural CO2 and metabolic CO2 eliminated via respiration. Scopes 2 and 3 (indirect) emissions related to capture, compression, and transportation of CO2 to hospitals and the disposal of single-use equipment not used in open surgery were calculated. Results The total CO2 emissions were calculated to be 355,924 tonnes/year. For perspective, if MIS in the United States was considered a country, it would rank 189th on the United Nations 2008 list of countries' carbon emissions per year. Limitations include the inability to account for uncertainty using the various models and tools for approximating CO2 emissions. Conclusion CO2 emission of MIS in the United States may have a significant environmental impact. This is the first attempt to quantify CO2 emissions related to MIS in the United States. Strategies for reduction, while maintaining high quality medical care, should be considered. PMID:22845049

  7. MIS Case Study: I-94 Rehabilitation Project - Detroit, Michigan.

    DOT National Transportation Integrated Search

    1997-01-01

    ISTEA includes specific requirements for inclusion in studies of Major Investment Projects in Metropolitan Planning Areas. The State of Michigan initiated a Major Investment Study (MIS) in October 1994 for the redesign and reconstruction of a 7 mile ...

  8. Investigating annually-resovled natural climate variability during MIS 11 using lacustrine records

    NASA Astrophysics Data System (ADS)

    Tye, G. J.; Palmer, A. P.; Candy, I.; Coxon, P.; Hardiman, M.

    2012-04-01

    Marine isotope stage 11 (MIS 11, ca 410,000 yrs BP) is considered to be one of the best analogues for current and future climate change due to the similarity of orbital forcing patterns during these two interglacials. Marine and ice-core records suggest that MIS 11 was a particularly long interglacial, characterised by stable climates. The investigation of high-resolution climate records from MIS 11 can, therefore, allow us to understand how the climate of a Holocene-like interglacial might evolve in the absence of anthropogenic modification. MIS 11 sediments preserved in the palaeolake basin at Marks Tey, eastern England, offer the potential for such a study as they are considered to be annually-laminated (varved) throughout a large part of the interglacial (Turner, 1970, 1975). The lamination sets appear to be comprised, primarily, of three regularly occurring laminae types; 1) authigenic carbonate, 2) diatom blooms, and 3) organic detritus, although there appears to be some variability in the microfacies of these laminations. The carbonate laminations are the key to the study of climate variability during MIS 11, as they represent authigenic carbonate precipitation, consistent with temperature/biologically driven changes in lake chemistry during the summer months. Oxygen isotopic analysis of the carbonate therefore gives a proxy for summer temperature. A period of key interest in the MIS 11 sequence at Marks Tey occurs during the early part of the interglacial, where there is a short-lived increase in grass pollen relative to tree pollen, termed the Non-Arboreal Pollen Zone (NAPZ). The cause of this shift in pollen has been subject to debate, with natural wildfire (Turner, 1970) or climatic deterioration (e.g. Kelly, 1964) being suggested as possible forcing mechanisms. In this study, as well as discussing the main characteristics of the MIS 11 sequence at Marks Tey, we will focus on the sedimentary, micromorphological and geochemical record of the NAPZ. In particular we discuss the potential role of abrupt, sub-Milankovitch, climate cooling in its genesis, whilst highlighting the complexity of ecological and landscape response that such a climatic event may generate. The study concludes by discussing the potential occurrence of 8.2ka-like events in pre-Holocene interglacials.

  9. Pleistocene environmental dynamics recorded in the loess of the middle and lower Danube basin

    NASA Astrophysics Data System (ADS)

    Fitzsimmons, Kathryn E.; Marković, Slobodan B.; Hambach, Ulrich

    2012-05-01

    The substantial loess deposits of the middle and lower Danube basin in southeastern Europe represent one of the thickest and most comprehensive terrestrial palaeoenvironmental records on the continent, yet are also the least well understood. Environmental conditions over the last million years have resulted in relatively continuous deposits uninterrupted by glaciation and tundra conditions, which nevertheless reflect oscillations between relatively warm-humid (“interglacial”) and cold-dry (“glacial”) intervals. This relative environmental stability may have proven important for hominins migrating into and through the region. The loess stratigraphy comprises distinct loess-paleosol sequences, reflecting glacial-interglacial phases which can be quantified for intensity using environmental magnetism and geochemistry. These phases are emphasised by variations in vegetation and malacofauna which respond to climatic change. The loess deposits demonstrate broadly similar sedimentological characteristics across the basin. Danubian loess deposits initiated in response to the tectonic formation of the Pannonian basin, retreat of the large palaeolakes, and increased sediment supply from the Danube. The period from ˜1 Ma-500 ka (MIS 27-13) was characterised by alternating loess deposition and pedogenesis during glacial and interglacial periods respectively, in response to relatively humid, forested conditions. This period represents the opening of the Danube corridor and provides the backdrop for initial hominin arrival into Europe. After ˜500 ka, and particularly after MIS 9, loess accumulation rates increased in response to relatively more steppic, arid, environments. MIS 9 and 13-15 were the most humid phases of the last ˜600 ky. The MIS 5 interglacial period was the warmest, and relatively most humid, period preceding the Holocene, and was followed by substantially increased loess accumulation during MIS 4, which may be linked to North Atlantic circulation. The complexity of the MIS 3 interstadial paleosol suggests that conditions were not uniformly warm and wet during this time. MIS 3 corresponds with the first arrival of anatomically modern humans to Europe. The last glacial maximum and Younger Dryas of MIS 2 were characterised by substantially increased loess accumulation indicating cold steppe environments most likely influenced by the North Atlantic, although conditions were sufficiently mild that the region acted as a refugium for thermophilic biota, as may also have been the case for most of the Pleistocene glacial cycles. The Holocene soil represents relatively wamer and more humid conditions corresponding to the current interglacial.

  10. Effect of graft source on unrelated donor hemopoietic stem cell transplantation in adults with acute myeloid leukemia after reduced-intensity or nonmyeloablative conditioning: a study from the Société Francaise de Greffe de Moelle et de Thérapie Cellulaire.

    PubMed

    Malard, Florent; Milpied, Noel; Blaise, Didier; Chevallier, Patrice; Michallet, Mauricette; Lioure, Bruno; Clément, Laurence; Hicheri, Yosr; Cordonnier, Catherine; Huynh, Anne; Yakoub-Agha, Ibrahim; Peffault de Latour, Regis; Mohty, Mohamad

    2015-06-01

    This retrospective report compared the 4-year outcomes of allogeneic stem cell transplantation (allo-SCT) in 651 adult patients with acute myeloid leukemia receiving a reduced-intensity (RIC) or nonmyeloablative conditioning (NMA) regimen according to the type of unrelated donors. These were either umbilical cord blood (UCB, n = 205), a 9/10 mismatched unrelated donor (MisMUD, n = 99), or a 10/10 matched unrelated donor (MUD, n = 347) graft. Neutrophil recovery was slower in UCB (74.5% by day 42) compared with MisMUD (94.8%) and MUD (95.6%) (P < .001). There was no significant difference in nonrelapse mortality between UCB and both MUD (hazard ratio [HR], 1.05; 95% confidence interval [CI], .62 to 1.78; P = .85) and MisMUD (HR, 1.58; 95% CI, .88 to 2.83; P = .13) The relapse/progression was similar between UCB and MisMUD (HR, .62; 95% CI, .37 to 1.03; P = .07), but was significantly lower in MUD compared with UCB (HR, .60; 95% CI, .39 to .92; P = .02). The rate of extensive chronic graft-versus-host disease (GVHD) was similar between UCB and both MUD (HR, 2.15; 95% CI, .93 to 4.97; P = .08) and MisMUD (HR, 1.84; 95% CI, .68 to 4.95; P = .23). The rate of severe grade III and IV acute GVHD was significantly increased in MisMUD compared with UCB (HR, 2.61; 95% CI, 1.30 to 5.23; P = .007). There was no significant difference in overall survival between UCB and both MisMUD (HR, .98; 95% CI, .66 to 1.45; P = .92) and MUD (HR, .74; 95% CI, .52 to 1.03; P = .08). These data suggest that in the setting of RIC/NMA, allo-SCT UCB is a valid alternative graft source, with significantly less chronic GVHD, compared with MisMUD, when there is no MUD available or when urgent transplantation is needed. Copyright © 2015 American Society for Blood and Marrow Transplantation. Published by Elsevier Inc. All rights reserved.

  11. Terahertz signal detection in a short gate length field-effect transistor with a two-dimensional electron gas

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Vostokov, N. V., E-mail: vostokov@ipm.sci-nnov.ru; Shashkin, V. I.

    2015-11-28

    We consider the problem of non-resonant detection of terahertz signals in a short gate length field-effect transistor having a two-dimensional electron channel with zero external bias between the source and the drain. The channel resistance, gate-channel capacitance, and quadratic nonlinearity parameter of the transistor during detection as a function of the gate bias voltage are studied. Characteristics of detection of the transistor connected in an antenna with real impedance are analyzed. The consideration is based on both a simple one-dimensional model of the transistor and allowance for the two-dimensional distribution of the electric field in the transistor structure. The resultsmore » given by the different models are discussed.« less

  12. Flexible Proton-Gated Oxide Synaptic Transistors on Si Membrane.

    PubMed

    Zhu, Li Qiang; Wan, Chang Jin; Gao, Ping Qi; Liu, Yang Hui; Xiao, Hui; Ye, Ji Chun; Wan, Qing

    2016-08-24

    Ion-conducting materials have received considerable attention for their applications in fuel cells, electrochemical devices, and sensors. Here, flexible indium zinc oxide (InZnO) synaptic transistors with multiple presynaptic inputs gated by proton-conducting phosphorosilicate glass-based electrolyte films are fabricated on ultrathin Si membranes. Transient characteristics of the proton gated InZnO synaptic transistors are investigated, indicating stable proton-gating behaviors. Short-term synaptic plasticities are mimicked on the proposed proton-gated synaptic transistors. Furthermore, synaptic integration regulations are mimicked on the proposed synaptic transistor networks. Spiking logic modulations are realized based on the transition between superlinear and sublinear synaptic integration. The multigates coupled flexible proton-gated oxide synaptic transistors may be interesting for neuroinspired platforms with sophisticated spatiotemporal information processing.

  13. Controllable film densification and interface flatness for high-performance amorphous indium oxide based thin film transistors

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Ou-Yang, Wei, E-mail: OUYANG.Wei@nims.go.jp, E-mail: TSUKAGOSHI.Kazuhito@nims.go.jp; Mitoma, Nobuhiko; Kizu, Takio

    2014-10-20

    To avoid the problem of air sensitive and wet-etched Zn and/or Ga contained amorphous oxide transistors, we propose an alternative amorphous semiconductor of indium silicon tungsten oxide as the channel material for thin film transistors. In this study, we employ the material to reveal the relation between the active thin film and the transistor performance with aid of x-ray reflectivity study. By adjusting the pre-annealing temperature, we find that the film densification and interface flatness between the film and gate insulator are crucial for achieving controllable high-performance transistors. The material and findings in the study are believed helpful for realizingmore » controllable high-performance stable transistors.« less

  14. Copper atomic-scale transistors

    PubMed Central

    Kavalenka, Maryna N; Röger, Moritz; Albrecht, Daniel; Hölscher, Hendrik; Leuthold, Jürgen

    2017-01-01

    We investigated copper as a working material for metallic atomic-scale transistors and confirmed that copper atomic-scale transistors can be fabricated and operated electrochemically in a copper electrolyte (CuSO4 + H2SO4) in bi-distilled water under ambient conditions with three microelectrodes (source, drain and gate). The electrochemical switching-on potential of the atomic-scale transistor is below 350 mV, and the switching-off potential is between 0 and −170 mV. The switching-on current is above 1 μA, which is compatible with semiconductor transistor devices. Both sign and amplitude of the voltage applied across the source and drain electrodes (U bias) influence the switching rate of the transistor and the copper deposition on the electrodes, and correspondingly shift the electrochemical operation potential. The copper atomic-scale transistors can be switched using a function generator without a computer-controlled feedback switching mechanism. The copper atomic-scale transistors, with only one or two atoms at the narrowest constriction, were realized to switch between 0 and 1G 0 (G 0 = 2e2/h; with e being the electron charge, and h being Planck’s constant) or 2G 0 by the function generator. The switching rate can reach up to 10 Hz. The copper atomic-scale transistor demonstrates volatile/non-volatile dual functionalities. Such an optimal merging of the logic with memory may open a perspective for processor-in-memory and logic-in-memory architectures, using copper as an alternative working material besides silver for fully metallic atomic-scale transistors. PMID:28382242

  15. A III-V nanowire channel on silicon for high-performance vertical transistors.

    PubMed

    Tomioka, Katsuhiro; Yoshimura, Masatoshi; Fukui, Takashi

    2012-08-09

    Silicon transistors are expected to have new gate architectures, channel materials and switching mechanisms in ten years' time. The trend in transistor scaling has already led to a change in gate structure from two dimensions to three, used in fin field-effect transistors, to avoid problems inherent in miniaturization such as high off-state leakage current and the short-channel effect. At present, planar and fin architectures using III-V materials, specifically InGaAs, are being explored as alternative fast channels on silicon because of their high electron mobility and high-quality interface with gate dielectrics. The idea of surrounding-gate transistors, in which the gate is wrapped around a nanowire channel to provide the best possible electrostatic gate control, using InGaAs channels on silicon, however, has been less well investigated because of difficulties in integrating free-standing InGaAs nanostructures on silicon. Here we report the position-controlled growth of vertical InGaAs nanowires on silicon without any buffering technique and demonstrate surrounding-gate transistors using InGaAs nanowires and InGaAs/InP/InAlAs/InGaAs core-multishell nanowires as channels. Surrounding-gate transistors using core-multishell nanowire channels with a six-sided, high-electron-mobility transistor structure greatly enhance the on-state current and transconductance while keeping good gate controllability. These devices provide a route to making vertically oriented transistors for the next generation of field-effect transistors and may be useful as building blocks for wireless networks on silicon platforms.

  16. Uracil misincorporation into DNA and folic acid supplementation

    USDA-ARS?s Scientific Manuscript database

    BACKGROUND: Folate deficiency decreases thymidylate synthesis from deoxyuridylate, which results in an imbalance of deoxyribonucleotide that may lead to excessive uracil misincorporation (UrMis) into DNA during replication and repair. OBJECTIVE: We evaluated the relation between UrMis in different ...

  17. The Role of Minimally Invasive Surgery in Pediatric Trauma.

    PubMed

    Pearson, Erik G; Clifton, Matthew S

    2017-02-01

    Minimally invasive surgery (MIS) in the management of blunt and penetrating pediatric trauma has evolved in the past 30 years. Laparoscopy and thoracoscopy possess high levels of diagnostic accuracy with low associated missed injury rates. Currently available data advocate limiting the use of MIS to blunt or penetrating injuries in the hemodynamically stable child. In the pediatric trauma population, MIS offers both diagnostic and therapeutic potential, as well as reduced postoperative pain, a decreased rate of postoperative complications, shortened hospital stay, and potentially reduced cost. Copyright © 2016 Elsevier Inc. All rights reserved.

  18. The monsoon imprint during the `atypical' MIS 13 as seen through north and equatorial Indian Ocean records

    NASA Astrophysics Data System (ADS)

    Caley, Thibaut; Malaizé, Bruno; Bassinot, Franck; Clemens, Steven C.; Caillon, Nicolas; Linda, Rossignol; Charlier, Karine; Rebaubier, Helene

    2011-09-01

    Previous studies have suggested that Marine Isotope Stage (MIS) 13, recognized as atypical in many paleoclimate records, is marked by the development of anomalously strong summer monsoons in the northern tropical areas. To test this hypothesis, we performed a multi-proxy study on three marine records from the tropical Indian Ocean in order to reconstruct and analyse changes in the summer Indian monsoon winds and precipitations during MIS 13. Our data confirm the existence of a low-salinity event during MIS 13 in the equatorial Indian Ocean but we argue that this event should not be considered as "atypical". Taking only into account a smaller precession does not make it possible to explain such precipitation episode. However, when considering also the larger obliquity in a more complete orbitally driven monsoon "model," one can successfully explain this event. In addition, our data suggest that intense summer monsoon winds, although not atypical in strength, prevailed during MIS 13 in the western Arabian Sea. These strong monsoon winds, transporting important moisture, together with the effect of insolation and Eurasian ice sheet, are likely one of the factors responsible for the intense monsoon precipitation signal recorded in China loess, as suggested by model simulations.

  19. Chironomid-based reconstructions of summer air temperature from lake deposits in Lyndon Stream, New Zealand spanning the MIS 3/2 transition

    NASA Astrophysics Data System (ADS)

    Woodward, C. A.; Shulmeister, J.

    2007-01-01

    We present chironomid-based temperature reconstructions from lake sediments deposited between ca 26,600 cal yr BP and 24,500 cal yr BP from Lyndon Stream, South Island, New Zealand. Summer (February mean) temperatures averaged 1 °C cooler, with a maximum inferred cooling of 3.7 °C. These estimates corroborate macrofossil and beetle-based temperature inferences from the same site and suggest climate amelioration (an interstadial) at this time. Other records from the New Zealand region also show a large degree of variability during the late Otiran glacial sequence (34,000-18,000 cal yr BP) including a phase of warming at the MIS 2/3 transition and a maximum cooling that did not occur until the global LGM (ca 20,000 cal yr BP). The very moderate cooling identified here at the MIS 2/3 transition confirms and enhances the long-standing discrepancy in New Zealand records between pollen and other proxies. Low abundances (<20%) of canopy tree pollen in records from late MIS 3 to the end of MIS 2 cannot be explained by the minor (<5 °C) cooling inferred from this and other studies unless other environmental parameters are considered. Further work is required to address this critical issue.

  20. Optically stimulated luminescence age controls on late Pleistocene and Holocene coastal lithosomes, North Carolina, USA

    USGS Publications Warehouse

    Mallinson, D.; Burdette, K.; Mahan, S.; Brook, G.

    2008-01-01

    Luminescence ages from a variety of coastal features on the North Carolina Coastal Plain provide age control for shoreline formation and relative sea-level position during the late Pleistocene. A series of paleoshoreline ridges, dating to Marine Isotope Stage (MIS) 5a and MIS 3 have been defined. The Kitty Hawk beach ridges, on the modern Outer Banks, yield ages of 3 to 2??ka. Oxygen-isotope data are used to place these deposits in the context of global climate and sea-level change. The occurrence of MIS 5a and MIS 3 shorelines suggests that glacio-isostatic adjustment (GIA) of the study area is large (ca. 22 to 26??m), as suggested and modeled by other workers, and/or MIS 3 sea level was briefly higher than suggested by some coral reef studies. Correcting the shoreline elevations for GIA brings their elevation in line with other sea-level indicators. The age of the Kitty Hawk beach ridges places the Holocene shoreline well west of its present location at ca. 3 to 2??ka. The age of shoreline progradation is consistent with the ages of other beach ridge complexes in the southeast USA, suggesting some regionally contemporaneous forcing mechanism. ?? 2007 University of Washington.

  1. Ergonomic assessment of neck posture in the minimally invasive surgery suite during laparoscopic cholecystectomy.

    PubMed

    van Det, M J; Meijerink, W J H J; Hoff, C; van Veelen, M A; Pierie, J P E N

    2008-11-01

    With the expanding implementation of minimally invasive surgery, the operating team is confronted with challenges in the field of ergonomics. Visual feedback is derived from a monitor placed outside the operating field. This crossover trial was conducted to evaluate and compare neck posture in relation to monitor position in a dedicated minimally invasive surgery (MIS) suite and a conventional operating room. Assessment of the neck was conducted for 16 surgeons, assisting surgeons, and scrub nurses performing a laparoscopic cholecystectomy in both types of operating room. Flexion and rotation of the cervical spine were measured intraoperatively using a video analysis system. A two-question visual analog scale (VAS) questionnaire was used to evaluate posture in relation to the monitor position. Neck rotation was significantly reduced in the MIS suite for the surgeon (p = 0.018) and the assisting surgeon (p < 0.001). Neck flexion was significantly improved in the MIS suite for the surgeon (p < 0.001) and the scrub nurse (p = 0.018). On the questionnaire, the operating room team scored their posture significantly higher in the MIS suite and also indicated fewer musculoskeletal complaints. The ergonomic quality of the neck posture is significantly improved in the MIS suite for the entire operating room team.

  2. [Quality of information analysis on basic causes of neonatal deaths recorded in the Mortality Information System: a study in Maceió, Alagoas State, Brazil, 2001-2002].

    PubMed

    Pedrosa, Linda Délia C O; Sarinho, Silvia W; Ordonha, Manoelina R

    2007-10-01

    Analysis of the quality of information on basic causes of neonatal deaths in Brazil is crucially important, since it allows one to estimate how many deaths are avoidable and provide support for policies to decrease neonatal mortality. The current study aimed to evaluate the reliability and validity of the Mortality Information System (MIS) for discriminating between basic causes of neonatal deaths and defining percentages of reducible causes. The basic causes of early neonatal deaths in hospitals in Maceió, Alagoas State, were analyzed, and the causes recorded in medical records were compared to the MIS data in order to measure reliability and validity. The modified SEADE Foundation and Wigglesworth classifications were compared to analyze the capacity for reduction of neonatal mortality. Maternal causes predominated in the medical records, as compared to respiratory disorders on the death certificates and in the MIS. The percentage of avoidable deaths may be much higher than observed from the MIS, due to imprecision in completing death certificates. Based on the MIS, the greatest problems are in early diagnosis and treatment of neonatal causes. However, the results show that the most pressing problems relate to failures in prenatal care and lack of control of diseases.

  3. Admittance of MIS-Structures Based on HgCdTe with a Double-Layer CdTe/Al2O3 Insulator

    NASA Astrophysics Data System (ADS)

    Dzyadukh, S. M.; Voitsekhovskii, A. V.; Nesmelov, S. N.; Sidorov, G. Yu.; Varavin, V. S.; Vasil'ev, V. V.; Dvoretsky, S. A.; Mikhailov, N. N.; Yakushev, M. V.

    2018-03-01

    Admittance of MIS structures based on n( p)- Hg1-xCdxTe (at x from 0.22 to 0.40) with SiO2/Si3N4, Al2O3, and CdTe/Al2O3 insulators is studied experimentally at 77 K. Growth of an intermediate CdTe layer during epitaxy results in the almost complete disappearance of the hysteresis of electrophysical characteristics of MIS structures based on graded-gap n-HgCdTe for a small range of the voltage variation. For a wide range of the voltage variation, the hysteresis of the capacitance-voltage characteristics appears for MIS structures based on n-HgCdTe with the CdTe/Al2O3 insulator. However, the hysteresis mechanism differs from that in case of a single-layer Al2O3 insulator. For MIS structures based on p-HgCdTe, introduction of an additional CdTe layer does not lead to a significant decrease of the hysteresis phenomena, which may be due to the degradation of the interface properties when mercury leaves the film as a result of low-temperature annealing changing the conductivity type of the semiconductor.

  4. Temperature-Dependent Electrical Properties and Carrier Transport Mechanisms of TMAH-Treated Ni/Au/Al2O3/GaN MIS Diode

    NASA Astrophysics Data System (ADS)

    Reddy, M. Siva Pratap; Puneetha, Peddathimula; Reddy, V. Rajagopal; Lee, Jung-Hee; Jeong, Seong-Hoon; Park, Chinho

    2016-11-01

    The temperature-dependent electrical properties and carrier transport mechanisms of tetramethylammonium hydroxide (TMAH)-treated Ni/Au/Al2O3/GaN metal-insulator-semiconductor (MIS) diodes have been investigated by current-voltage ( I- V) and capacitance-voltage ( C- V) measurements. The experimental results reveal that the barrier height ( I- V) increases whereas the ideality factor decreases with increasing temperature. The TMAH-treated Ni/Au/Al2O3/GaN MIS diode showed nonideal behaviors which indicate the presence of a nonuniform distribution of interface states ( N SS) and effect of series resistance ( R S). The obtained R S and N SS were found to decrease with increasing temperature. Furthermore, it was found that different transport mechanisms dominated in the TMAH-treated Ni/Au/Al2O3/GaN MIS diode. At 150 K to 250 K, Poole-Frenkel emission (PFE) was found to be responsible for the reverse leakage, while Schottky emission (SE) was the dominant mechanism at high electric fields in the temperature range from 300 K to 400 K. Feasible energy band diagrams and possible carrier transport mechanisms for the TMAH-treated Ni/Au/Al2O3/GaN MIS diode are discussed based on PFE and SE.

  5. Paleoecological and climatic implications of stable isotope results from late Pleistocene bone collagen, Ziegeleigrube Coenen, Germany

    NASA Astrophysics Data System (ADS)

    Wißing, Christoph; Matzerath, Simon; Turner, Elaine; Bocherens, Hervé

    2015-07-01

    Climatic and ecological conditions during Marine Oxygen Isotope Stage (MIS) 3 are complex and the impact of cold spells on the ecosystems in Central Europe still needs to be investigated thoroughly. Ziegeleigrube Coenen (ZC) is a late Pleistocene MIS 3 locality in the Lower Rhine Embayment of Germany, radiocarbon-dated to > 34 14C ka BP. The site yielded a broad spectrum of mammal species. We investigated the carbon (δ13C), nitrogen (δ15N) and sulfur (δ34S) isotope signatures of bone collagen, since these are valuable tools in characterizing ecological niches, environmental conditions and aspects of climate and mobility. By comparison with pre- and post-Last Glacial Maximum (LGM) sites in Central Europe we show that ZC belongs in a cold event of MIS 3 and was climatically more similar to post-LGM sites than to pre-LGM sites. However, the trophic structure resembled that of typical pre-LGM sites in Belgium. This cold event in MIS 3 changed the bottom of the foodweb, but do not seem to have had a direct impact on the occurrence of the mammalian species and their ecological distribution. Apparently the (mega-) faunal community could adapt also to harsher environmental conditions during MIS 3.

  6. Transmission line relay mis-operation detection based on time-synchronized field data

    DOE PAGES

    Esmaeilian, Ahad; Popovic, Tomo; Kezunovic, Mladen

    2015-05-04

    In this paper, a real-time tool to detect transmission line relay mis-operation is implemented. The tool uses time-synchronized measurements obtained from both ends of the line during disturbances. The proposed fault analysis tool comes into the picture only after the protective device has operated and tripped the line. The proposed methodology is able not only to detect, classify, and locate transmission line faults, but also to accurately confirm whether the line was tripped due to a mis-operation of protective relays. The analysis report includes either detailed description of the fault type and location or detection of relay mis-operation. As such,more » it can be a source of very useful information to support the system restoration. The focus of the paper is on the implementation requirements that allow practical application of the methodology, which is illustrated using the field data obtained the real power system. Testing and validation is done using the field data recorded by digital fault recorders and protective relays. The test data included several hundreds of event records corresponding to both relay mis-operations and actual faults. The discussion of results addresses various challenges encountered during the implementation and validation of the presented methodology.« less

  7. Late Quaternary uplift rate across the Shimokita peninsula, northeastern Japan forearc

    NASA Astrophysics Data System (ADS)

    Matsu'Ura, T.

    2009-12-01

    I estimated the late Quaternary uplift rate across the northeastern Japan forearc (Shimokita peninsula) by using the height distribution of MIS 5.5 marine terraces as determined from tephra and cryptotephra stratigraphy. The heights of inner-margins (shoreline angles) of the MIS 5.5 marine terrace surface were previously reported to be 43-45 m and 30 m around Shiriyazaki and Gamanosawa, respectively. These heights decrease westward and are possibly due to a west-dipping offshore fault. But in some places, the heights of terrace inner-margins are probably overestimated by thick sediments. I found the MIS 5.5 wave-cut platform which is overlain by gravels and loess deposits containing a basal Toya tephra horizon (MIS 5.4) at Shiriyazaki by boring. The MIS 5.5 wave-cut platform (paleo sea level) is about 25 m above sea level, nearly half of the reported height of the terrace inner-margin. My result shows that the late Quaternary uplift rate across the Shimokita peninsula should be reconsidered. Further studies are also required whether or not the intra-plate (offshore) fault is a factor of the forearc uplifting at the peninsula. This research project has been conducted under the research contract with Nuclear and Industrial Safety Agency (NISA).

  8. Contrasting pollen histories of MIS 5e and the Holocene from Lake Titicaca (Bolivia/Peru)

    NASA Astrophysics Data System (ADS)

    Hanselman, Jennifer A.; Gosling, William D.; Paduano, Gina M.; Bush, Mark B.

    2005-10-01

    Two long sediment records (cores LTO1-2B and LT01-3B) from Lake Titicaca, Bolivia/Peru, are compared with a previously analysed Holocene record from this lake (core NE98-1PC). The Holocene records of LT01-2B and NE98-1PC are similar. There are striking differences, however, between the MIS 5e sections of the long cores and the Holocene records. In these records, temperature is probably the dominant parameter that determines the total fossil pollen concentration and is used to time the onset and termination of deglaciation. In contrast, the relative and absolute abundance of specific taxa (e.g. Polylepis/Acaena, Chenopodiaceae) are indicators of relative moisture availability. Although the Holocene contains a period of aridity between ca. 8000 cal. yr BP and 4300 cal. yr BP, it is a minor event compared with the more extreme aridity of MIS 5e. Core LT01-3B showed similar trends during MIS 5e when compared to LT01-2B, as did NE98-1PC when comparing Holocene records. MIS 5e and the Holocene are markedly different interglacials, depicted by shifts in pollen concentration and taxa representation over time.

  9. Perioperative outcomes and adverse events of minimally invasive versus open posterior lumbar fusion: meta-analysis and systematic review.

    PubMed

    Goldstein, Christina L; Macwan, Kevin; Sundararajan, Kala; Rampersaud, Y Raja

    2016-03-01

    The objective of this study was to determine the clinical comparative effectiveness and adverse event rates of posterior minimally invasive surgery (MIS) compared with open transforaminal or posterior lumbar interbody fusion (TLIF/PLIF). A systematic review of the Medline, EMBASE, PubMed, Web of Science, and Cochrane databases was performed. A hand search of reference lists was conducted. Studies were reviewed by 2 independent assessors to identify randomized controlled trials (RCTs) or comparative cohort studies including at least 10 patients undergoing MIS or open TLIF/PLIF for degenerative lumbar spinal disorders and reporting at least 1 of the following: clinical outcome measure, perioperative clinical or process measure, radiographic outcome, or adverse events. Study quality was assessed using the Grades of Recommendation, Assessment, Development, and Evaluation (GRADE) protocol. When appropriate, a meta-analysis of outcomes data was conducted. The systematic review and reference list search identified 3301 articles, with 26 meeting study inclusion criteria. All studies, including 1 RCT, were of low or very low quality. No significant difference regarding age, sex, surgical levels, or diagnosis was identified between the 2 cohorts (856 patients in the MIS cohort, 806 patients in the open cohort). The meta-analysis revealed changes in the perioperative outcomes of mean estimated blood loss, time to ambulation, and length of stay favoring an MIS approach by 260 ml (p < 0.00001), 3.5 days (p = 0.0006), and 2.9 days (p < 0.00001), respectively. Operative time was not significantly different between the surgical techniques (p = 0.78). There was no significant difference in surgical adverse events (p = 0.97), but MIS cases were significantly less likely to experience medical adverse events (risk ratio [MIS vs open] = 0.39, 95% confidence interval 0.23-0.69, p = 0.001). No difference in nonunion (p = 0.97) or reoperation rates (p = 0.97) was observed. Mean Oswestry Disability Index scores were slightly better in the patients undergoing MIS (n = 346) versus open TLIF/PLIF (n = 346) at a median follow-up time of 24 months (mean difference [MIS - open] = 3.32, p = 0.001). The result of this quantitative systematic review of clinical comparative effectiveness research examining MIS versus open TLIF/PLIF for degenerative lumbar pathology suggests equipoise in patient-reported clinical outcomes. Furthermore, a meta-analysis of adverse event data suggests equivalent rates of surgical complications with lower rates of medical complications in patients undergoing minimally invasive TLIF/PLIF compared with open surgery. The quality of the current comparative evidence is low to very low, with significant inherent bias.

  10. Undegassed Carbon Content from a Highly Depleted Segment of the Mid-Atlantic Ridge (1-5°S): Evidence from Melt Inclusions

    NASA Astrophysics Data System (ADS)

    Le Voyer, M.; Kelley, K. A.; Cottrell, E.; Hauri, E. H.

    2014-12-01

    As carbon solubility is low in basalts, MORB contain little dissolved CO2 (189±61 ppm, 1σ, n=600 [1]). A global negative correlation between CO2/Nb (proxy for amount of CO2 lost by degassing) and Ba/La (proxy for source enrichment) indicates that depleted MORB are less affected by degassing than enriched MORB: CO2/Nb ratios range from 0-100 for samples with Ba/La>4, while CO2/Nb range from 50 to 400 for samples with Ba/La<4 [1]. To assess the CO2 content of undegassed MORB, we analyzed the volatile content of 70 olivine-hosted, glassy melt inclusions (MIs) from four basalts dredged along MAR 1-5°S, a ridge segment that produces highly depleted MORB in terms of trace element enrichment and radiogenic isotopes [2, 3]. MIs contain CO2 contents (180-1420 ppm) that are higher than their respective matrix glasses (130-220 ppm, typical for vapor-saturated melts erupted at 3-5 km b.s.l.). One of the four dredges (EN061 5D-3Ag) contains MIs that do not exhibit shrinkage bubbles. For this sample only, we find a positive correlation between the CO2 content (240-770 ppm) and the Cl content (6-20 ppm) of the MIs that is not found in the matrix glasses (see Fig.). We infer that the correlation between CO2 and Cl, both highly incompatible in silicate minerals during fractional crystallization, is strong evidence for vapor-undersaturation, as any CO2 degassing would have erased the correlation. Together with MIs from the Siqueiros Fracture Zone [4] and from northern Iceland [5], the MIs from EN061 5D-3Ag may represent another occurrence of carbon-undersaturated MORB. Our results will be used to model the primary carbon content of MORB and of the depleted upper mantle. Note that the average Cl content of the matrix glasses (20±1 ppm) is higher than those of the MIs (12±3 ppm, see Fig.). This indicates either that the matrix glasses assimilated a small amount of seawater Cl, or that the MIs are all more depleted than the matrix glass. We will acquire major and trace element data in order to further investigate the origin of the low Cl and high CO2 contents in these MIs. Ref. [1] Le Voyer et al. 2014 Goldschmidt abstr. [2] Schilling et al. 1994 JGR 99 [3] Kelley et al. 2013 G3 [4] Saal et al. 2002 Nature 419 [5] Hauri and Saal 2009 EOS Fall suppl. AGU abstr.

  11. High voltage power transistor development

    NASA Technical Reports Server (NTRS)

    Hower, P. L.

    1981-01-01

    Design considerations, fabrication procedures, and methods of evaluation for high-voltage power-transistor development are discussed. Technique improvements such as controlling the electric field at the surface and perserving lifetimes in the collector region which have advanced the state of the art in high-voltage transistors are discussed. These improvements can be applied directly to the development of 1200 volt, 200 ampere transistors.

  12. Metal Oxide Silicon /MOS/ transistors protected from destructive damage by wire

    NASA Technical Reports Server (NTRS)

    Deboo, G. J.; Devine, E. J.

    1966-01-01

    Loop of flexible, small diameter, nickel wire protects metal oxide silicon /MOS/ transistors from a damaging electrostatic potential. The wire is attached to a music-wire spring, slipped over the MOS transistor case, and released so the spring tensions the wire loop around all the transistor leads, shorting them together. This allows handling without danger of damage.

  13. 19 CFR 10.13 - Statutory provision: Subheading 9802.00.80, Harmonized Tariff Schedule of the United States (19 U...

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... the exemption bears to the full value of the assembled article. Example 1. A transistor radio is assembled abroad from foreign-made components and American-made transistors. Upon importation, the transistor radio is subject to the ad valorem rate of duty applicable to transistor radios upon the value of...

  14. 19 CFR 10.13 - Statutory provision: Subheading 9802.00.80, Harmonized Tariff Schedule of the United States (19 U...

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... the exemption bears to the full value of the assembled article. Example 1. A transistor radio is assembled abroad from foreign-made components and American-made transistors. Upon importation, the transistor radio is subject to the ad valorem rate of duty applicable to transistor radios upon the value of...

  15. 19 CFR 10.13 - Statutory provision: Subheading 9802.00.80, Harmonized Tariff Schedule of the United States (19 U...

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... the exemption bears to the full value of the assembled article. Example 1. A transistor radio is assembled abroad from foreign-made components and American-made transistors. Upon importation, the transistor radio is subject to the ad valorem rate of duty applicable to transistor radios upon the value of...

  16. 19 CFR 10.13 - Statutory provision: Subheading 9802.00.80, Harmonized Tariff Schedule of the United States (19 U...

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... the exemption bears to the full value of the assembled article. Example 1. A transistor radio is assembled abroad from foreign-made components and American-made transistors. Upon importation, the transistor radio is subject to the ad valorem rate of duty applicable to transistor radios upon the value of...

  17. 19 CFR 10.13 - Statutory provision: Subheading 9802.00.80, Harmonized Tariff Schedule of the United States (19 U...

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... the exemption bears to the full value of the assembled article. Example 1. A transistor radio is assembled abroad from foreign-made components and American-made transistors. Upon importation, the transistor radio is subject to the ad valorem rate of duty applicable to transistor radios upon the value of...

  18. Three-Dimensional, Inkjet-Printed Organic Transistors and Integrated Circuits with 100% Yield, High Uniformity, and Long-Term Stability.

    PubMed

    Kwon, Jimin; Takeda, Yasunori; Fukuda, Kenjiro; Cho, Kilwon; Tokito, Shizuo; Jung, Sungjune

    2016-11-22

    In this paper, we demonstrate three-dimensional (3D) integrated circuits (ICs) based on a 3D complementary organic field-effect transistor (3D-COFET). The transistor-on-transistor structure was achieved by vertically stacking a p-type OFET over an n-type OFET with a shared gate joining the two transistors, effectively halving the footprint of printed transistors. All the functional layers including organic semiconductors, source/drain/gate electrodes, and interconnection paths were fully inkjet-printed except a parylene dielectric which was deposited by chemical vapor deposition. An array of printed 3D-COFETs and their inverter logic gates comprising over 100 transistors showed 100% yield, and the uniformity and long-term stability of the device were also investigated. A full-adder circuit, the most basic computing unit, has been successfully demonstrated using nine NAND gates based on the 3D structure. The present study fulfills the essential requirements for the fabrication of organic printed complex ICs (increased transistor density, 100% yield, high uniformity, and long-term stability), and the findings can be applied to realize more complex digital/analogue ICs and intelligent devices.

  19. Scaling of Device Variability and Subthreshold Swing in Ballistic Carbon Nanotube Transistors

    NASA Astrophysics Data System (ADS)

    Cao, Qing; Tersoff, Jerry; Han, Shu-Jen; Penumatcha, Ashish V.

    2015-08-01

    In field-effect transistors, the inherent randomness of dopants and other charges is a major cause of device-to-device variability. For a quasi-one-dimensional device such as carbon nanotube transistors, even a single charge can drastically change the performance, making this a critical issue for their adoption as a practical technology. Here we calculate the effect of the random charges at the gate-oxide surface in ballistic carbon nanotube transistors, finding good agreement with the variability statistics in recent experiments. A combination of experimental and simulation results further reveals that these random charges are also a major factor limiting the subthreshold swing for nanotube transistors fabricated on thin gate dielectrics. We then establish that the scaling of the nanotube device uniformity with the gate dielectric, fixed-charge density, and device dimension is qualitatively different from conventional silicon transistors, reflecting the very different device physics of a ballistic transistor with a quasi-one-dimensional channel. The combination of gate-oxide scaling and improved control of fixed-charge density should provide the uniformity needed for large-scale integration of such novel one-dimensional transistors even at extremely scaled device dimensions.

  20. Top-gated chemical vapor deposition grown graphene transistors with current saturation.

    PubMed

    Bai, Jingwei; Liao, Lei; Zhou, Hailong; Cheng, Rui; Liu, Lixin; Huang, Yu; Duan, Xiangfeng

    2011-06-08

    Graphene transistors are of considerable interest for radio frequency (rf) applications. In general, transistors with large transconductance and drain current saturation are desirable for rf performance, which is however nontrivial to achieve in graphene transistors. Here we report high-performance top-gated graphene transistors based on chemical vapor deposition (CVD) grown graphene with large transconductance and drain current saturation. The graphene transistors were fabricated with evaporated high dielectric constant material (HfO(2)) as the top-gate dielectrics. Length scaling studies of the transistors with channel length from 5.6 μm to 100 nm show that complete current saturation can be achieved in 5.6 μm devices and the saturation characteristics degrade as the channel length shrinks down to the 100-300 nm regime. The drain current saturation was primarily attributed to drain bias induced shift of the Dirac points. With the selective deposition of HfO(2) gate dielectrics, we have further demonstrated a simple scheme to realize a 300 nm channel length graphene transistors with self-aligned source-drain electrodes to achieve the highest transconductance of 250 μS/μm reported in CVD graphene to date.

  1. Reprogrammable read only variable threshold transistor memory with isolated addressing buffer

    DOEpatents

    Lodi, Robert J.

    1976-01-01

    A monolithic integrated circuit, fully decoded memory comprises a rectangular array of variable threshold field effect transistors organized into a plurality of multi-bit words. Binary address inputs to the memory are decoded by a field effect transistor decoder into a plurality of word selection lines each of which activates an address buffer circuit. Each address buffer circuit, in turn, drives a word line of the memory array. In accordance with the word line selected by the decoder the activated buffer circuit directs reading or writing voltages to the transistors comprising the memory words. All of the buffer circuits additionally are connected to a common terminal for clearing all of the memory transistors to a predetermined state by the application to the common terminal of a large magnitude voltage of a predetermined polarity. The address decoder, the buffer and the memory array, as well as control and input/output control and buffer field effect transistor circuits, are fabricated on a common substrate with means provided to isolate the substrate of the address buffer transistors from the remainder of the substrate so that the bulk clearing function of simultaneously placing all of the memory transistors into a predetermined state can be performed.

  2. Enhanced Amplification and Fan-Out Operation in an All-Magnetic Transistor

    PubMed Central

    Barman, Saswati; Saha, Susmita; Mondal, Sucheta; Kumar, Dheeraj; Barman, Anjan

    2016-01-01

    Development of all-magnetic transistor with favorable properties is an important step towards a new paradigm of all-magnetic computation. Recently, we showed such possibility in a Magnetic Vortex Transistor (MVT). Here, we demonstrate enhanced amplification in MVT achieved by introducing geometrical asymmetry in a three vortex sequence. The resulting asymmetry in core to core distance in the three vortex sequence led to enhanced amplification of the MVT output. A cascade of antivortices travelling in different trajectories including a nearly elliptical trajectory through the dynamic stray field is found to be responsible for this amplification. This asymmetric vortex transistor is further used for a successful fan-out operation, which gives large and nearly equal gains in two output branches. This large amplification in magnetic vortex gyration in magnetic vortex transistor is proposed to be maintained for a network of vortex transistor. The above observations promote the magnetic vortex transistors to be used in complex circuits and logic operations. PMID:27624662

  3. DEVICE TECHNOLOGY. Nanomaterials in transistors: From high-performance to thin-film applications.

    PubMed

    Franklin, Aaron D

    2015-08-14

    For more than 50 years, silicon transistors have been continuously shrunk to meet the projections of Moore's law but are now reaching fundamental limits on speed and power use. With these limits at hand, nanomaterials offer great promise for improving transistor performance and adding new applications through the coming decades. With different transistors needed in everything from high-performance servers to thin-film display backplanes, it is important to understand the targeted application needs when considering new material options. Here the distinction between high-performance and thin-film transistors is reviewed, along with the benefits and challenges to using nanomaterials in such transistors. In particular, progress on carbon nanotubes, as well as graphene and related materials (including transition metal dichalcogenides and X-enes), outlines the advances and further research needed to enable their use in transistors for high-performance computing, thin films, or completely new technologies such as flexible and transparent devices. Copyright © 2015, American Association for the Advancement of Science.

  4. Ultra-high gain diffusion-driven organic transistor

    PubMed Central

    Torricelli, Fabrizio; Colalongo, Luigi; Raiteri, Daniele; Kovács-Vajna, Zsolt Miklós; Cantatore, Eugenio

    2016-01-01

    Emerging large-area technologies based on organic transistors are enabling the fabrication of low-cost flexible circuits, smart sensors and biomedical devices. High-gain transistors are essential for the development of large-scale circuit integration, high-sensitivity sensors and signal amplification in sensing systems. Unfortunately, organic field-effect transistors show limited gain, usually of the order of tens, because of the large contact resistance and channel-length modulation. Here we show a new organic field-effect transistor architecture with a gain larger than 700. This is the highest gain ever reported for organic field-effect transistors. In the proposed organic field-effect transistor, the charge injection and extraction at the metal–semiconductor contacts are driven by the charge diffusion. The ideal conditions of ohmic contacts with negligible contact resistance and flat current saturation are demonstrated. The approach is general and can be extended to any thin-film technology opening unprecedented opportunities for the development of high-performance flexible electronics. PMID:26829567

  5. Large-scale complementary macroelectronics using hybrid integration of carbon nanotubes and IGZO thin-film transistors.

    PubMed

    Chen, Haitian; Cao, Yu; Zhang, Jialu; Zhou, Chongwu

    2014-06-13

    Carbon nanotubes and metal oxide semiconductors have emerged as important materials for p-type and n-type thin-film transistors, respectively; however, realizing sophisticated macroelectronics operating in complementary mode has been challenging due to the difficulty in making n-type carbon nanotube transistors and p-type metal oxide transistors. Here we report a hybrid integration of p-type carbon nanotube and n-type indium-gallium-zinc-oxide thin-film transistors to achieve large-scale (>1,000 transistors for 501-stage ring oscillators) complementary macroelectronic circuits on both rigid and flexible substrates. This approach of hybrid integration allows us to combine the strength of p-type carbon nanotube and n-type indium-gallium-zinc-oxide thin-film transistors, and offers high device yield and low device variation. Based on this approach, we report the successful demonstration of various logic gates (inverter, NAND and NOR gates), ring oscillators (from 51 stages to 501 stages) and dynamic logic circuits (dynamic inverter, NAND and NOR gates).

  6. Bottom-Up Tri-gate Transistors and Submicrosecond Photodetectors from Guided CdS Nanowalls.

    PubMed

    Xu, Jinyou; Oksenberg, Eitan; Popovitz-Biro, Ronit; Rechav, Katya; Joselevich, Ernesto

    2017-11-08

    Tri-gate transistors offer better performance than planar transistors by exerting additional gate control over a channel from two lateral sides of semiconductor nanowalls (or "fins"). Here we report the bottom-up assembly of aligned CdS nanowalls by a simultaneous combination of horizontal catalytic vapor-liquid-solid growth and vertical facet-selective noncatalytic vapor-solid growth and their parallel integration into tri-gate transistors and photodetectors at wafer scale (cm 2 ) without postgrowth transfer or alignment steps. These tri-gate transistors act as enhancement-mode transistors with an on/off current ratio on the order of 10 8 , 4 orders of magnitude higher than the best results ever reported for planar enhancement-mode CdS transistors. The response time of the photodetector is reduced to the submicrosecond level, 1 order of magnitude shorter than the best results ever reported for photodetectors made of bottom-up semiconductor nanostructures. Guided semiconductor nanowalls open new opportunities for high-performance 3D nanodevices assembled from the bottom up.

  7. Universal power transistor base drive control unit

    DOEpatents

    Gale, Allan R.; Gritter, David J.

    1988-01-01

    A saturation condition regulator system for a power transistor which achieves the regulation objectives of a Baker clamp but without dumping excess base drive current into the transistor output circuit. The base drive current of the transistor is sensed and used through an active feedback circuit to produce an error signal which modulates the base drive current through a linearly operating FET. The collector base voltage of the power transistor is independently monitored to develop a second error signal which is also used to regulate base drive current. The current-sensitive circuit operates as a limiter. In addition, a fail-safe timing circuit is disclosed which automatically resets to a turn OFF condition in the event the transistor does not turn ON within a predetermined time after the input signal transition.

  8. Universal power transistor base drive control unit

    DOEpatents

    Gale, A.R.; Gritter, D.J.

    1988-06-07

    A saturation condition regulator system for a power transistor is disclosed which achieves the regulation objectives of a Baker clamp but without dumping excess base drive current into the transistor output circuit. The base drive current of the transistor is sensed and used through an active feedback circuit to produce an error signal which modulates the base drive current through a linearly operating FET. The collector base voltage of the power transistor is independently monitored to develop a second error signal which is also used to regulate base drive current. The current-sensitive circuit operates as a limiter. In addition, a fail-safe timing circuit is disclosed which automatically resets to a turn OFF condition in the event the transistor does not turn ON within a predetermined time after the input signal transition. 2 figs.

  9. Transistor-based filter for inhibiting load noise from entering a power supply

    DOEpatents

    Taubman, Matthew S

    2013-07-02

    A transistor-based filter for inhibiting load noise from entering a power supply is disclosed. The filter includes a first transistor having an emitter coupled to a power supply, a collector coupled to a load, and a base. The filter also includes a first capacitor coupled between the base of the first transistor and a ground terminal. The filter further includes an impedance coupled between the base and a node between the collector and the load, or a second transistor and second capacitor. The impedance can be a resistor or an inductor.

  10. Transistor-based filter for inhibiting load noise from entering a power supply

    DOEpatents

    Taubman, Matthew S

    2015-02-24

    A transistor-based filter for inhibiting load noise from entering a power supply is disclosed. The filter includes a first transistor having an emitter coupled to a power supply, a collector coupled to a load, and a base. The filter also includes a first capacitor coupled between the base of the first transistor and a ground terminal The filter further includes an impedance coupled between the base and a node between the collector and the load, or a second transistor and second capacitor. The impedance can be a resistor or an inductor.

  11. Transistor circuit increases range of logarithmic current amplifier

    NASA Technical Reports Server (NTRS)

    Gilmour, G.

    1966-01-01

    Circuit increases the range of a logarithmic current amplifier by combining a commercially available amplifier with a silicon epitaxial transistor. A temperature compensating network is provided for the transistor.

  12. The Changing Environment of Management Information Systems.

    ERIC Educational Resources Information Center

    Tagawa, Ken

    1982-01-01

    The promise of mainframe computers in the 1970s for management information systems (MIS) is largely unfulfilled, and newer office automation systems and data communication systems are designed to be responsive to MIS needs. The status of these innovations is briefly outlined. (MSE)

  13. Cognitive Processes and Students' Misconceptions in Science.

    ERIC Educational Resources Information Center

    Smith, Deborah C.

    Several categories of misconceptions which appear to be emerging across studies are discussed. They include: mis-perceptions; stunted conceptions; mis-translations; confused conceptions; lost conceptions; and true misconceptions. True misconceptions are metaphors and analogies which represent truly complete systems of explanation but are…

  14. Application of the Johnson criteria to graphene transistors

    NASA Astrophysics Data System (ADS)

    Kelly, M. J.

    2013-12-01

    For 60 years, the Johnson criteria have guided the development of materials and the materials choices for field-effect and bipolar transistor technology. Intrinsic graphene is a semi-metal, precluding transistor applications, but only under lateral bias is a gap opened and transistor action possible. This first application of the Johnson criteria to biased graphene suggests that this material will struggle to ever achieve competitive commercial applications.

  15. Assessment of Phospohrene Field Effect Transistors

    DTIC Science & Technology

    2018-01-28

    electronics industry. To this end, transistor test structures would initially be fabricated on phosphorene exfoliated from black phosphorus and, later, on...34Phosphorene FETs-Promising Transistors Based on a few Layers of Phosphorus Atoms," Nanjing Electronic Devices Institute, Nanjing, China, Jul. 2015...OH, Nov. 2015. J.C. M. Hwang, "Phosphorene Transistors-Transient or Lasting Electronics ?" Workshop Frontier Electronics , San Juan, PR, Dec. 2015

  16. Subtractive Plasma-Assisted-Etch Process for Developing High Performance Nanocrystalline Zinc-Oxide Thin-Film-Transistors

    DTIC Science & Technology

    2015-03-26

    THIN - FILM - TRANSISTORS THESIS Thomas M. Donigan, First Lieutenant, USAF AFIT-ENG-MS-15-M-027 DEPARTMENT OF THE AIR FORCE AIR UNIVERSITY AIR...DEVELOPING HIGH PERFORMANCE NANOCRYSTALLINE ZINC-OXIDE THIN - FILM - TRANSISTORS THESIS Presented to the Faculty Department of Electrical and...15-M-027 SUBTRACTIVE PLASMA-ASSISTED-ETCH PROCESS FOR DEVELOPING HIGH PERFORMANCE NANOCRYSTALLINE ZINC-OXIDE THIN - FILM - TRANSISTORS

  17. Oxide Based Transistor for Flexible Displays

    DTIC Science & Technology

    2014-09-15

    thin film transistors (TFTs) for next generation display technologies. A detailed and comprehensive study was carried out to ascertain the process...Box 12211 Research Triangle Park, NC 27709-2211 Thin film transistors , flexible electronics, RF sputtering, Transparent amorphous oxide semiconductors...NC A&T and RTI, International investigated In free GaSnZnO (GSZO) material system, as the active channel in thin film transistors (TFTs) for next

  18. Coaxial inverted geometry transistor having buried emitter

    NASA Technical Reports Server (NTRS)

    Hruby, R. J.; Cress, S. B.; Dunn, W. R. (Inventor)

    1973-01-01

    The invention relates to an inverted geometry transistor wherein the emitter is buried within the substrate. The transistor can be fabricated as a part of a monolithic integrated circuit and is particularly suited for use in applications where it is desired to employ low actuating voltages. The transistor may employ the same doping levels in the collector and emitter, so these connections can be reversed.

  19. Transistor Laser Optical NOR Gate for High Speed Optical Logic Processors

    DTIC Science & Technology

    2017-03-20

    proposes an optical bistable latch can be built with two universal photonic NOR gate circuits, which are implemented by the three-port tunneling ... Tunneling Junction Transistor Laser (TJ-TL); Optical NOR Gate. Introduction To fulfill the future national security and intelligence needs in this...two-terminal diode lasers. Three-Port Transistor Laser – an Integration of Quantum-Wells into Heterojunction Bipolar Transistor Different than

  20. Field-effect transistors (2nd revised and enlarged edition)

    NASA Astrophysics Data System (ADS)

    Bocharov, L. N.

    The design, principle of operation, and principal technical characteristics of field-effect transistors produced in the USSR are described. Problems related to the use of field-effect transistors in various radioelectronic devices are examined, and tables of parameters and mean statistical characteristics are presented for the main types of field-effect transistors. Methods for calculating various circuit components are discussed and illustrated by numerical examples.

  1. PRESSURE TRANSDUCER

    DOEpatents

    Sander, H.H.

    1959-10-01

    A pressure or mechanical force transducer particularly adaptable to miniature telemetering systems is described. Basically the device consists of a transistor located within a magnetic field adapted to change in response to mechanical force. The conduction characteristics of the transistor in turn vary proportionally with changes in the magnetic flux across the transistor such that the output (either frequency of amplitude) of the transistor circuit is proportional to mechanical force or pressure.

  2. Single-transistor-clocked flip-flop

    DOEpatents

    Zhao, Peiyi; Darwish, Tarek; Bayoumi, Magdy

    2005-08-30

    The invention provides a low power, high performance flip-flop. The flip-flop uses only one clocked transistor. The single clocked transistor is shared by the first and second branches of the device. A pulse generator produces a clock pulse to trigger the flip-flop. In one preferred embodiment the device can be made as a static explicit pulsed flip-flop which employs only two clocked transistors.

  3. Millennial-scale variability to 735 ka: High-resolution climate records from Santa Barbara Basin, CA

    NASA Astrophysics Data System (ADS)

    White, Sarah M.; Hill, Tessa M.; Kennett, James P.; Behl, Richard J.; Nicholson, Craig

    2013-06-01

    Determining the ultimate cause and effect of millennial-scale climate variability remains an outstanding problem in paleoceanography, partly due to the lack of high-resolution records predating the last glaciation. Recent cores from Santa Barbara Basin provide 2500-5700 year "windows" of climate with 10-50 year resolution. Ages for three cores, determined by seismic stratigraphic correlation, oxygen isotope stratigraphy, and biostratigraphy, date to 293 ka (MIS 8), 450 ka (MIS 12), and 735 ka (MIS 18). These records sample the Late Pleistocene, during which the 100 kyr cycle strengthened and the magnitude of glacial-interglacial cyclicity increased. Thus, these records provide a test of the dependence of millennial-scale behavior on variations in glacial-interglacial cyclicity. The stable isotopic (δ18O) composition of planktonic foraminifera shows millennial-scale variability in all three intervals, with similar characteristics (duration, cyclicity) to those previously documented during MIS 3 at this site. Stadial G. bulloides δ18O values are 2.75-1.75‰ (average 2.25‰) and interstadial values are 1.75-0.5‰ (average 1‰), with rapid (decadal-scale) interstadial and stadial initiations of 1-2‰, as in MIS 3. Interstadials lasted 250-1600 years and occurred every 650-1900 years. Stadial paleotemperatures were 3.5-9.5°C and interstadial paleotemperatures were 7.5-13°C. Upwelling, evidenced by planktonic foraminiferal assemblages and δ13C, increased during interstadials, similar to MIS 3; high productivity during some stadials was reminiscent of the Last Glacial Maximum. This study builds upon previous records in showing that millennial-scale shifts were an inherent feature of Northern Hemisphere glacial climates since 735 ka, and they remained remarkably constant in the details of their amplitude, cyclicity, and temperature variability.

  4. New chronology of the best developed loess/paleosol sequence of Hungary capturing the past 1.1 ma: Implications for correlation and proposed pan-Eurasian stratigraphic schemes

    NASA Astrophysics Data System (ADS)

    Sümegi, P.; Gulyás, S.; Molnár, D.; Sümegi, B. P.; Almond, P. C.; Vandenberghe, J.; Zhou, L.; Pál-Molnár, E.; Törőcsik, T.; Hao, Q.; Smalley, I.; Molnár, M.; Marsi, I.

    2018-07-01

    In this paper, we are presenting a revised chronology of the best developed, longest (100 m) LPS in Hungary dating back 1.1 Ma: borehole Udvari-2A. It is based on a non-tuned age-depth model, built on the position of the Matuyama-Brunhes Boundary, Jaramillo and Olduvai Subchrons. Furthermore, on the assignment of formerly recorded uninterpreted geomagnetic reversals in both chrons. Other chronometric tools (AMS 14C dating, biostratigraphy, tephrostratigraphy) yielding absolute ages and/or ensuring validation of these were also used. Records of a Middle Pleistocene gastropod index fossil Neostyriaca corynodes (400 -140 ka) facilitated verification of ages between MIS 10 and MIS 6. Multiple age control points at 15, 25, 27, 45, 120, 191, 362, 430, 670, 780, 900, 990, 1070 ka were established for the last ca. 1.1 Ma. The resulting chronology is the best resolved independent one so far among Danubian Basin LPSs. In light of our data, the S3-S4 units were fused as S3 in all Serbian, and some Romanian sites and re-correlated with MIS 9. The results also point to a misassignment of the S5 units at these sites to MIS 13-15 leading to erroneous conclusions regarding paleoclimatic conditions and cyclicity. In our new stratigraphic scheme, these S5 paleosols were taken to represent the S4 paleosol and recorrelated with MIS 11. Finally, an ideal stratigraphic column dating back 1.1 Ma for SW Hungary was constructed and correlated with the Chinese loess/paleosol sequence of Xifeng and the benthic oxygen isotope record down to MIS 31.

  5. Minimally invasive surgery for pedal digital deformity: an audit of complications using national benchmark indicators.

    PubMed

    Gilheany, Mark; Baarini, Omar; Samaras, Dean

    2015-01-01

    There is increasing global interest and performance of minimally invasive foot surgery (MIS) however, limited evidence is available in relation to complications associated with MIS for digital deformity correction. The aim of this prospective audit is to report the surgical and medical complications following MIS for digital deformity against standardised clinical indicators. A prospective clinical audit of 179 patients who underwent MIS to reduce simple and complex digital deformities was conducted between June 2011 and June 2013. All patients were followed up to a minimum of 12 months post operatively. Data was collected according to a modified version of the Australian Council of Healthcare standards (ACHS) clinical indicator program. The audit was conducted in accordance with the National Research Ethics Service (NRES) guidelines on clinical audit. The surgical complications included 1 superficial infection (0.53%) and 2 under-corrected digits (0.67%), which required revision surgery. Two patients who underwent isolated complex digital corrections had pain due to delayed union (0.7%), which resolved by 6 months post-op. No neurovascular compromise and no medical complications were encountered. The results compare favourably to rates reported in the literature for open reduction of digital deformity. This audit has illustrated that performing MIS to address simple and complex digital deformity results in low complication rates compared to published standards. MIS procedures were safely performed in a range of clinical settings, on varying degrees of digital deformity and on a wide range of ages and health profiles. Further studies investigating the effectiveness of these techniques are warranted and should evaluate long term patient reported outcome measures, as well as developing treatment algorithms to guide clinical decision making.

  6. Mode change of millennial CO2 variability during the last glacial cycle associated with a bipolar marine carbon seesaw

    PubMed Central

    Bereiter, Bernhard; Lüthi, Dieter; Siegrist, Michael; Schüpbach, Simon; Stocker, Thomas F.; Fischer, Hubertus

    2012-01-01

    Important elements of natural climate variations during the last ice age are abrupt temperature increases over Greenland and related warming and cooling periods over Antarctica. Records from Antarctic ice cores have shown that the global carbon cycle also plays a role in these changes. The available data shows that atmospheric CO2 follows closely temperatures reconstructed from Antarctic ice cores during these variations. Here, we present new high-resolution CO2 data from Antarctic ice cores, which cover the period between 115,000 and 38,000 y before present. Our measurements show that also smaller Antarctic warming events have an imprint in CO2 concentrations. Moreover, they indicate that during Marine Isotope Stage (MIS) 5, the peak of millennial CO2 variations lags the onset of Dansgaard/Oeschger warmings by 250 ± 190 y. During MIS 3, this lag increases significantly to 870 ± 90 y. Considerations of the ocean circulation suggest that the millennial variability associated with the Atlantic Meridional Overturning Circulation (AMOC) undergoes a mode change from MIS 5 to MIS 4 and 3. Ocean carbon inventory estimates imply that during MIS 3 additional carbon is derived from an extended mass of carbon-enriched Antarctic Bottom Water. The absence of such a carbon-enriched water mass in the North Atlantic during MIS 5 can explain the smaller amount of carbon released to the atmosphere after the Antarctic temperature maximum and, hence, the shorter lag. Our new data provides further constraints for transient coupled carbon cycle-climate simulations during the entire last glacial cycle. PMID:22675123

  7. MIS 5e sea levels and `superstorms': what the integration of field data and modelling can tell us?

    NASA Astrophysics Data System (ADS)

    Rovere, A.; Raymo, M. E.; O'Leary, M.; Stocchi, P.; Vacchi, M.; Lorscheid, T.; Harris, D. L.; Casella, E.; Nandasena, N. A. K.; Sandstrom, R. M.; D'Andrea, W. J.; Dyer, B.

    2016-12-01

    The Last Interglacial (MIS 5e, 128-116 ka) is among the most studied past periods in Earth's history. The climate at that time was warmer than today, primarily due to different orbital conditions, with smaller ice sheets and higher sea level. Understanding the climate system, and in particular sea level, during MIS 5e is essential to understand the behavior of ice sheets in a warmer world. Two questions in particular remain unsolved: was there a meltwater pulse towards the end of the interglacial? Was the same period characterized by superstorms? Thousands of studies spanning more than a century report information on MIS 5e RSL indicators. Despite the large quantity of field data available, the two questions formulated above remain unanswered. This is due to different reasons. In first instance, relative sea-level (RSL) indicators and field interpretations may carry large uncertainties. Second, processes such as tectonics are difficult to isolate and quantify independently. In this presentation, we will describe the strategies that can be adopted to minimize the uncertainties associated with paleo RSL calculations, and we show the limits of `tectonic stability' assumptions based on the position of MIS 5e shorelines. We then show that the combination of high-resolution topographic methods (e.g. GPS, photogrammetry from UAVs and detailed bathymetry) with scenarios dictated by GIA and coastal hydrodynamic models is essential to gather insights not only on the indicative meaning of RSL indicators, but also on the hypothesis that the last period of MIS 5e was characterized by `superstorms' (as defined by Hansen, J. et al. Atmos. Chem. Phys. Discuss. 15, 2015).

  8. Effect on neurostimulation of injectates used for perineural space expansion before placement of a stimulating catheter: normal saline versus dextrose 5% in water.

    PubMed

    Pham Dang, Charles; Lelong, Aurélie; Guilley, Jérôme; Nguyen, Jean Michel; Volteau, Christelle; Venet, Guillaume; Perrier, Cyril; Lejus, Corinne; Blanloeil, Yvonnick

    2009-01-01

    We clinically assessed the electrophysiologic effect of dextrose 5% in water (D5W) and of normal saline (NS) used for expansion of the perineural space before placing a stimulating catheter. We questioned if higher current was required with NS but not with D5W, as has been observed experimentally. This was a prospective randomized double-blind study of ASA I to II patients scheduled for total knee replacement. Patients from 2 hospitals were randomly assigned to receive unidentified injectate D5W (n = 25) or NS (n = 25). The primary outcome was the minimal intensity of stimulation (MIS) recorded before and after 2 and 5 mL of study injectates were flushed through the needle before placing a stimulating catheter for continuous femoral and sciatic nerve blocks. Secondary outcomes included, among other parameters, MIS recorded during placement of stimulating catheters. No difference between groups was found with MIS before injection. However, MIS recorded during neurostimulation via the needle in all blocks was significantly higher after 2 and 5 mL of NS than after D5W. In femoral blocks, MIS recorded during placement of catheters was higher during insertion after NS than after D5W but was not different after reaching the final site, regardless of injectate used. In sciatic blocks, MIS was not different during insertion regardless of injectate but was higher after NS than after D5W after reaching the final site. The current needed to electrostimulate the femoral or sciatic nerve was higher after injection of NS than after D5W.

  9. SAGES's advanced GI/MIS fellowship curriculum pilot project.

    PubMed

    Weis, Joshua J; Goldblatt, Matthew; Pryor, Aurora; Dunkin, Brian J; Brunt, L Michael; Jones, Daniel B; Scott, Daniel J

    2018-06-01

    The American health care system faces deficits in quality and quantity of surgeons. SAGES is a major stakeholder in surgical fellowship training and is responsible for defining the curriculum for the Advanced GI/MIS fellowship. SAGES leadership is actively adapting this curriculum. The process of reform began in 2014 through a series of iterative meetings and discussions. A working group within the Resident and Fellow Training Committee reviewed case log data from 2012 to 2015. These data were used to propose new criteria designed to provide adequate exposure to core content. The working group also proposed using video assessment of an MIS case to provide objective assessment of competency. Case log data were available for 326 fellows with a total of 85,154 cases logged (median 227 per fellow). The working group proposed new criteria starting with minimum case volumes for five defined categories including foregut (20), bariatrics (25), inguinal hernia (10), ventral hernia (10), and solid organ/colon/thoracic (10). Fellows are expected to perform an additional 75 complex MIS cases of any category for a total of 150 required cases overall. The proposal also included a minimum volume of flexible endoscopy (50) and submission of an MIS foregut case for video assessment. The new criteria more clearly defined which surgeon roles count for major credit within individual categories. Fourteen fellowships volunteered to pilot these new criteria for the 2017-2018 academic year. The new SAGES Advanced GI/MIS fellowship has been crafted to better define the core content that should be contained in these fellowships, while still allowing sufficient heterogeneity so that individual learners can tailor their training to specific areas of interest. The criteria also introduce innovative, evidence-based methods for assessing competency. Pending the results of the pilot program, SAGES will consider broad implementation of the new fellowship criteria.

  10. Mode change of millennial CO2 variability during the last glacial cycle associated with a bipolar marine carbon seesaw.

    PubMed

    Bereiter, Bernhard; Lüthi, Dieter; Siegrist, Michael; Schüpbach, Simon; Stocker, Thomas F; Fischer, Hubertus

    2012-06-19

    Important elements of natural climate variations during the last ice age are abrupt temperature increases over Greenland and related warming and cooling periods over Antarctica. Records from Antarctic ice cores have shown that the global carbon cycle also plays a role in these changes. The available data shows that atmospheric CO(2) follows closely temperatures reconstructed from Antarctic ice cores during these variations. Here, we present new high-resolution CO(2) data from Antarctic ice cores, which cover the period between 115,000 and 38,000 y before present. Our measurements show that also smaller Antarctic warming events have an imprint in CO(2) concentrations. Moreover, they indicate that during Marine Isotope Stage (MIS) 5, the peak of millennial CO(2) variations lags the onset of Dansgaard/Oeschger warmings by 250 ± 190 y. During MIS 3, this lag increases significantly to 870 ± 90 y. Considerations of the ocean circulation suggest that the millennial variability associated with the Atlantic Meridional Overturning Circulation (AMOC) undergoes a mode change from MIS 5 to MIS 4 and 3. Ocean carbon inventory estimates imply that during MIS 3 additional carbon is derived from an extended mass of carbon-enriched Antarctic Bottom Water. The absence of such a carbon-enriched water mass in the North Atlantic during MIS 5 can explain the smaller amount of carbon released to the atmosphere after the Antarctic temperature maximum and, hence, the shorter lag. Our new data provides further constraints for transient coupled carbon cycle-climate simulations during the entire last glacial cycle.

  11. Stability of kinetochore-microtubule attachment and the role of different KMN network components in Drosophila.

    PubMed

    Feijão, Tália; Afonso, Olga; Maia, André F; Sunkel, Claudio E

    2013-10-01

    Kinetochores bind spindle microtubules and also act as signaling centers that monitor this interaction. Defects in kinetochore assembly lead to chromosome missegregation and aneuploidy. The interaction between microtubules and chromosomes involves a conserved super-complex of proteins, known as the KNL1Mis12Ndc80 (KMN) network, composed by the KNL1 (Spc105), Mis12, and Ndc80 complexes. Previous studies indicate that all components of the network are required for kinetochore-microtubule attachment and all play relevant functions in chromosome congression, biorientation, and segregation. Here, we report a comparative study addressing the role of the different KMN components using dsRNA and in vivo fluorescence microscopy in Drosophila S2 cells allowing us to suggest that different KMN network components might perform different roles in chromosome segregation and the mitotic checkpoint signaling. Depletion of different components results in mostly lateral kinetochore-microtubule attachments that are relatively stable on depletion of Mis12 or Ndc80 but very unstable after Spc105 depletion. In vivo analysis on depletion of Mis12, Ndc80, and to some extent Spc105, shows that lateral kinetochore-microtubule interactions are still functional allowing poleward kinetochore movement. We also find that different KMN network components affect differently the localization of spindle assembly checkpoint (SAC) proteins at kinetochores. Depletion of Ndc80 and Spc105 abolishes the mitotic checkpoint, whereas depletion of Mis12 causes a delay in mitotic progression. Taken together, our results suggest that Mis12 and Ndc80 complexes help to properly orient microtubule attachment, whereas Spc105 plays a predominant role in the kinetochore-microtubule attachment as well as in the poleward movement of chromosomes, SAC response, and cell viability. Copyright © 2013 Wiley Periodicals, Inc.

  12. Minimally invasive "separation surgery" plus adjuvant stereotactic radiotherapy in the management of spinal epidural metastases.

    PubMed

    Turel, Mazda K; Kerolus, Mena G; O'Toole, John E

    2017-01-01

    This study aimed to describe the application of minimally invasive surgery (MIS) in separation surgery combined with postoperative stereotactic body radiation therapy (SBRT) in patients with symptomatic metastatic epidural spinal disease. Three techniques are described: (1) MIS posterior separation surgery alone, (2) MIS posterolateral separation surgery with percutaneous pedicle screw placement, and (3) MIS lateral corpectomy with percutaneous pedicle screw placement. Seven representative cases are presented in which the above techniques were applied and after which postoperative SBRT was performed. The seven representative patients (3 male, 4 female) had a mean age of 54 years (range, 46-62 years). Two patients had a primary diagnosis of cholangiocarcinoma and in one patient each a diagnosis of breast, renal, lung adenocarcinoma, melanoma, and urothelial squamous cell carcinoma as their primary tumor. All patients had additional multiorgan disease apart from the metastatic spine involvement. Three patients underwent operations in the lumbar spine, two in the thoracic spine, and one in each of the thoraco-lumbar and lumbo-sacral spine. The average operating time was 149 ± 60.3 min (range, 90-240 min). The mean estimated blood loss was 188.8 cc. The mean length of stay in the hospital was 4 days (range, 3-7 days). There were no surgical complications. All patients received postoperative SBRT (typically 24 Gy in 3 fractions) at a mean of 43.2 days after surgery (range, 30-83). Early reports such as this suggest that MIS techniques can be successfully and safely applied in accomplishing "separation surgery" with adjuvant SBRT in the management of metastatic spinal disease. The potential advantages conferred by MIS techniques such as shortened hospital stay, decreased blood loss, reduced perioperative complications, and earlier initiation of adjuvant radiation are highly desirable in the treatment of this challenging patient population.

  13. Magnetic induction spectroscopy: non-contact measurement of the electrical conductivity spectra of biological samples

    NASA Astrophysics Data System (ADS)

    Barai, A.; Watson, S.; Griffiths, H.; Patz, R.

    2012-08-01

    Measurement of the electrical conductivity of biological tissues as a function of frequency, often termed ‘bioelectrical impedance spectroscopy (BIS)’, provides valuable information on tissue structure and composition. In implementing BIS though, there can be significant practical difficulties arising from the electrode-sample interface which have likely limited its deployment in industrial applications. In magnetic induction spectroscopy (MIS) these difficulties are eliminated through the use of fully non-contacting inductive coupling between the sensors and sample. However, inductive coupling introduces its own set of technical difficulties, primarily related to the small magnitudes of the induced currents and their proportionality with frequency. This paper describes the design of a practical MIS system incorporating new, highly-phase-stable electronics and compares its performance with that of electrode-based BIS in measurements on biological samples including yeast suspensions in saline (concentration 50-400 g l-1) and solid samples of potato, cucumber, tomato, banana and porcine liver. The shapes of the MIS spectra were in good agreement with those for electrode-based BIS, with a residual maximum discrepancy of 28%. The measurement precision of the MIS was 0.05 S m-1 at 200 kHz, improving to 0.01 S m-1 at a frequency of 20 MHz, for a sample volume of 80 ml. The data-acquisition time for each MIS measurement was 52 s. Given the value of spectroscopic conductivity information and the many advantages of obtaining these data in a non-contacting manner, even through electrically-insulating packaging materials if necessary, it is concluded that MIS is a technique with considerable potential for monitoring bio-industrial processes and product quality.

  14. Late Pleistocene lithostratigraphy and sequences in the southwestern Mesopotamia (Argentina): Evidences of the last interglacial stage

    NASA Astrophysics Data System (ADS)

    Ernesto, Brunetto; Soledad, Ferrero Brenda; Ignacio, Noriega Jorge

    2015-03-01

    The aim of this paper is to show the stratigraphic record of the Late Pleistocene corresponding to the distal region of the Paraná River basin. It displays sedimentological, paleontological and geochronological evidences that characterise the last interglacial-glacial cycle. In particular, strong environmental records are shown for the Last Interglacial Stage (LIS). Salto Ander Egg Formation (SAEF) is defined as a new lithostratigraphic unit representative of the Late Pleistocene in southwestern Mesopotamia. This unit is formed of complex fluvial deposits, which contains a heterogeneous collection of sub-environments, of ages ranging from 120 to 60 ky BP. The clast-supported gravel facies containing sparse boulders indicate high flow during a humid climate. The large and middle-scale architectures of fluvial sedimentary bodies evidence the relationship between the sediment accommodation and the sea level oscillations. Three sub-sequences identified in the succession suggest a transgressive trend during the MIS5e, a highstand stage in MIS5c, and a minor transgressive cycle during MIS3. A Brazilian faunal association collected at the bottom of the sequence and sedimentological interpretations display wet and warm climatic conditions, typical of tropical or subtropical environments. Such environmental conditions are characteristic of the maximum of the last interglacial stage (MIS5e) and show a signal stronger than the signal of the current interglacial stage. All these data show a direct correlation between the increases of paleodischarges and the elevation of the sea level. The whole sequence is completed with transitional swampy deposits, accumulated probably during the MIS3/MIS2 transition, and the typical loess of the Tezanos Pinto Formation, mantled during the Last Maximum Glacial.

  15. Knee Extensor Strength and Gait Characteristics After Minimally Invasive Unicondylar Knee Arthroplasty vs Minimally Invasive Total Knee Arthroplasty: A Nonrandomized Controlled Trial.

    PubMed

    Braito, Matthias; Giesinger, Johannes M; Fischler, Stefan; Koller, Arnold; Niederseer, David; Liebensteiner, Michael C

    2016-08-01

    In light of the existing lack of evidence, it was the aim of this study to compare gait characteristics and knee extensor strength after medial unicondylar knee arthroplasty (MUKA) with those after total knee arthroplasty (TKA), given the same standardized minimally invasive surgery (MIS) approach in both groups. Patients scheduled for MIS-MUKA or MIS-TKA as part of clinical routine were invited to participate. A posterior cruciate ligament-retaining total knee design was used for all MIS-TKA. A 3-dimensional gait analysis was performed preoperatively with a VICON system and at 8 weeks postoperative to determine temporospatial parameters, ground reaction forces, joint angles, and joint moments. At the same 2 times, isokinetic tests were performed to obtain peak values of knee extensor torque. A multivariate analysis of variance was conducted and included the main effects time (before and after surgery) and surgical group and the group-by-time interaction effect. Fifteen MIS-MUKA patients and 17 MIS-TKA patients were eligible for the final analysis. The groups showed no differences regarding age, body mass index, sex, side treated, or stage of osteoarthritis. We determined neither intergroup differences nor time × group interactions for peak knee extensor torque or any gait parameters (temporospatial, ground reaction forces, joint angles, and joint moments). It is concluded that MUKA is not superior to TKA with regard to knee extensor strength or 3-dimensional gait characteristics at 8 weeks after operation. As gait characteristics and knee extensor strength are only 2 of the various potential outcome parameters (knee scores, activity scores…) and quadriceps strength might take a longer time to recover, our findings should be interpreted with caution. Copyright © 2016 The Authors. Published by Elsevier Inc. All rights reserved.

  16. The Top 50 Articles on Minimally Invasive Spine Surgery.

    PubMed

    Virk, Sohrab S; Yu, Elizabeth

    2017-04-01

    Bibliometric study of current literature. To catalog the most important minimally invasive spine (MIS) surgery articles using the amount of citations as a marker of relevance. MIS surgery is a relatively new tool used by spinal surgeons. There is a dynamic and evolving field of research related to MIS techniques, clinical outcomes, and basic science research. To date, there is no comprehensive review of the most cited articles related to MIS surgery. A systematic search was performed over three widely used literature databases: Web of Science, Scopus, and Google Scholar. There were four searches performed using the terms "minimally invasive spine surgery," "endoscopic spine surgery," "percutaneous spinal surgery," and "lateral interbody surgery." The amount of citations included was averaged amongst the three databases to rank each article. The query of the three databases was performed in November 2015. Fifty articles were selected based upon the amount of citations each averaged amongst the three databases. The most cited article was titled "Extreme Lateral Interbody Fusion (XLIF): a novel surgical technique for anterior lumbar interbody fusion" by Ozgur et al and was credited with 447, 239, and 279 citations in Google Scholar, Web of Science, and Scopus, respectively. Citations ranged from 27 to 239 for Web of Science, 60 to 279 for Scopus, and 104 to 462 for Google Scholar. There was a large variety of articles written spanning over 14 different topics with the majority dealing with clinical outcomes related to MIS surgery. The majority of the most cited articles were level III and level IV studies. This is likely due to the relatively recent nature of technological advances in the field. Furthermore level I and level II studies are required in MIS surgery in the years ahead. 5.

  17. The ESA Mice in Space (MIS) habitat: effects of cage confinement on neuromusculoskeletal structure and function and stress/behavior using wild-type C57Bl/6JRj mice in a modular science reference model (MSRM) test on ground

    NASA Astrophysics Data System (ADS)

    Blottner, Dieter; Vico, Laurence; Jamon, D. Berckmansp L. Vicop Y. Liup R. Canceddap M.

    Background: Environmental conditions likely affect physiology and behaviour of mice used for Life Sciences Research on Earth and in Space. Thus, mice habitats with sufficient statistical numbers should be developed for adequate life support and care and that should meet all nesces-sary ethical and scientific requirements needed to successfully perform animal experimentation in Space. Aim of study: We here analysed the effects of cage confinement on the weightbear-ing musculoskeletal system, behaviour and stress of wild-type mice (C57BL/6JRj, 30 g b.wt., total n = 24) housed for 25 days in a prototypical ground-based MSRM (modular science ref-erence module) in the frame of breadboard activities for a fully automated life support habitat called "Mice in Space" (MIS) at the Leuven University, Belgium. Results: Compared with control housing (individually ventilated cages, IVC-mice) the MIS mice revealed no significant changes in soleus muscle size and myofiber distribution (type I vs. II) and quality of bone (3-D microarchitecture and mineralisation of calvaria, spine and femur) determined by confocal and micro-computed tomography. Corticosterone metabolism measured non-invasively (faeces) monitored elevated adrenocortical activity at only start of the MIS cage confinement (day 1). Behavioural tests (i.e., grip strength, rotarod, L/D box, elevated plus-maze, open field, ag-gressiveness) performed subsequently revealed only minor changes in motor performance (MIS vs. controls). Conclusions: The MIS habitat will not, on its own, produce major effects that could confound interpretation of data induced by microgravity exposure on orbit as planned for future biosatellite programmes. Sponsors: ESA-ESTEC, Noordwijk, NL

  18. Tracking dust deposition around the North Pacific Gyre over the past 500kyr

    NASA Astrophysics Data System (ADS)

    Costa, K.; McManus, J. F.; Winckler, G.; Anderson, R. F.; Middleton, J. L.; Mukhopadhyay, S.

    2017-12-01

    Across the North Pacific, dust delivery and distribution depends on atmospheric transport and precipitation, and dust fluxes generally decrease with distance away from the Asian continent. While it is well established that dust fluxes vary on glacial-interglacial timescales, how the dust distribution from the source to the sediment may have evolved is poorly constrained, largely due to a lack of long dust flux records from this region. Here we reconstruct dust flux variability from six piston cores on the Juan de Fuca Ridge in the Northeastern Pacific over the past 500kyr using 232Th as a lithogenic tracer and 230Th normalization to calculate fluxes. Minimal spatial variability between the six cores allows the compilation of a single regional dust flux stack. Dust fluxes vary by a factor of two between glacial, high-dust flux, and interglacial, low-dust flux periods, consistent with global patterns. Interglacial periods MIS7 and MIS9 dust fluxes remain relatively high compared to the adjacent glacial periods MIS6 and MIS 8 so that dust fluxes are fairly constant (3.3±0.6 ug 232Th/cm2kyr) from 135-335ka, excepting the high-lithogenic feature at 272ka (turbidite). Dust fluxes may be highest in MIS10 (6.0 ug 232Th/cm2kyr) than more recent glacial periods, for example MIS2 (3.9 ug 232Th/cm2kyr). Five multicores add high-resolution data for the last 30kyr. We compare these new records from the Northeast Pacific with dust flux records from the Northwest Pacific and the Equatorial Pacific to better constrain how dust deposition varied at different locations around the North Pacific Gyre on glacial-interglacial timescales.

  19. Limit load solution for electron beam welded joints with single edge weld center crack in tension

    NASA Astrophysics Data System (ADS)

    Lu, Wei; Shi, Yaowu; Li, Xiaoyan; Lei, Yongping

    2012-05-01

    Limit loads are widely studied and several limit load solutions are proposed to some typical geometry of weldments. However, there are no limit load solutions exist for the single edge crack weldments in tension (SEC(T)), which is also a typical geometry in fracture analysis. The mis-matching limit load for thick plate with SEC(T) are investigated and the special limit load solutions are proposed based on the available mis-matching limit load solutions and systematic finite element analyses. The real weld configurations are simplified as a strip, and different weld strength mis-matching ratio M, crack depth/width ratio a/ W and weld width 2H are in consideration. As a result, it is found that there exists excellent agreement between the limit load solutions and the FE results for almost all the mis-matching ration M, a/ W and ligament-to-weld width ratio ( W-a)/ H. Moreover, useful recommendations are given for evaluating the limit loads of the EBW structure with SEC(T). For the EBW joints with SEC(T), the mis-matching limit loads can be obtained assuming that the components are wholly made of base metal, when M changing from 1.6 to 0.6. When M decreasing to 0.4, the mis-matching limit loads can be obtained assuming that the components are wholly made of base metal only for large value of ( W-a)/ H. The recommendations may be useful for evaluating the limit loads of the EBW structures with SEC(T). The engineering simplifications are given for assessing the limit loads of electron beam welded structure with SEC(T).

  20. Impacts of polar ice sheets on the East Asian monsoon during the MIS-13 interglacial

    NASA Astrophysics Data System (ADS)

    Shi, Feng; Yin, Qiuzhen; Nikolova, Irina; Guo, Zhengtang; Berger, Andre

    2017-04-01

    Among all the interglacials of the last one million years, Marine Isotope Stage (MIS) 13 has the highest δ18O value over the past 800 ka in the deep-sea sediments. This would indicate that MIS-13 is the coolest interglacial if assuming δ18O mainly represents global ice volume. The Antarctic ice core records show also that MIS-13 is the coolest interglacial over Antarctica with almost the lowest greenhouse gases concentrations (GHG). However, many proxy records from the northern hemisphere (NH) indicate that MIS-13 is at least as warm as or even warmer than the recent interglacials, with extremely strong summer monsoon and a possible melting of Greenland ice sheet. In this study, based on proxy reconstructions, different scenarios regarding the size of the Greenland and Antarctic ice sheets are made, and the response of the East Asian summer monsoon to these scenarios are tested by using the models HadCM3 and LOVECLIM as well as factor separation analysis and under the astronomical and GHG configurations of MIS-13. The results show that the influence of the disappearance of Greenland ice sheet on the surface temperature is quite localized, mainly over the northern high latitudinal regions, however, the influence of the bigger southern Hemisphere (SH) ice sheet on the surface temperature is very global, especially in the southern hemisphere. This ice sheet condition has an impact on the precipitation pattern over tropical-subtropical regions. It causes much more summer precipitation over all the East Asian monsoon region, in consistent with the paleosol record from southern China. The scenario of melted Greenland ice sheet and of larger SH ice sheets provides one of the explanations of the strong monsoon rainfall documented by the proxy data.

  1. Boron nitride housing cools transistors

    NASA Technical Reports Server (NTRS)

    1965-01-01

    Boron nitride ceramic heat sink cools transistors in r-f transmitter and receiver circuits. Heat dissipated by the transistor is conducted by the boron nitride housing to the metal chassis on which it is mounted.

  2. Current sensing circuit

    NASA Technical Reports Server (NTRS)

    Franke, Ralph J. (Inventor)

    1996-01-01

    A current sensing circuit is described in which a pair of bipolar transistors are arranged with a pair of field effect transistors such that the field effect transistors absorb most of the supply voltage associated with a load.

  3. 78 FR 56737 - Privacy Act of 1974; System of Records

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-09-13

    ... system as the ``Organized Crime Drug Enforcement Task Forces Management Information System'' (OCDETF MIS... Task Forces Management Information System (OCDETF MIS). SECURITY CLASSIFICATION: Unclassified. SYSTEM... Office of Management and Budget (OMB) Circular No. A-130, notice is hereby given that the Department of...

  4. Strategic Planning for Management Information Systems.

    ERIC Educational Resources Information Center

    Ein-Dor, Phillip; Segev, Eli

    1978-01-01

    Two factors predominate in determining the appropriateness of strategic plans for management information systems (MIS)--explicitness (the degree to which the process is conscious, formal, and documented) and situational fit (the degree to which the MIS is compatible with the specific organization and its members). (Author/IRT)

  5. Three dimensional-stacked complementary thin-film transistors using n-type Al:ZnO and p-type NiO thin-film transistors.

    PubMed

    Lee, Ching-Ting; Chen, Chia-Chi; Lee, Hsin-Ying

    2018-03-05

    The three dimensional inverters were fabricated using novel complementary structure of stacked bottom n-type aluminum-doped zinc oxide (Al:ZnO) thin-film transistor and top p-type nickel oxide (NiO) thin-film transistor. When the inverter operated at the direct voltage (V DD ) of 10 V and the input voltage from 0 V to 10 V, the obtained high performances included the output swing of 9.9 V, the high noise margin of 2.7 V, and the low noise margin of 2.2 V. Furthermore, the high performances of unskenwed inverter were demonstrated by using the novel complementary structure of the stacked n-type Al:ZnO thin-film transistor and p-type nickel oxide (NiO) thin-film transistor.

  6. Tunable organic transistors that use microfluidic source and drain electrodes

    NASA Astrophysics Data System (ADS)

    Maltezos, George; Nortrup, Robert; Jeon, Seokwoo; Zaumseil, Jana; Rogers, John A.

    2003-09-01

    This letter describes a type of transistor that uses conducting fluidic source and drain electrodes of mercury which flow on top of a thin film of the organic semiconductor pentacene. Pumping the mercury through suitably designed microchannels changes the width of the transistor channel and, therefore, the electrical characteristics of the device. Measurements on transistors with a range of channel lengths reveal low contact resistances between mercury and pentacene. Data collected before, during, and after pumping the mercury through the microchannels demonstrate reversible and systematic tuning of the devices. This unusual type of organic transistor has the potential to be useful in plastic microfluidic devices that require active elements for pumps, sensors, or other components. It also represents a noninvasive way to build transistor test structures that incorporate certain classes of chemically and mechanically fragile organic semiconductors.

  7. Apparatus and method for recharging a string a avalanche transistors within a pulse generator

    DOEpatents

    Fulkerson, E. Stephen

    2000-01-01

    An apparatus and method for recharging a string of avalanche transistors within a pulse generator is disclosed. A plurality of amplification stages are connected in series. Each stage includes an avalanche transistor and a capacitor. A trigger signal, causes the apparatus to generate a very high voltage pulse of a very brief duration which discharges the capacitors. Charge resistors inject current into the string of avalanche transistors at various points, recharging the capacitors. The method of the present invention includes the steps of supplying current to charge resistors from a power supply; using the charge resistors to charge capacitors connected to a set of serially connected avalanche transistors; triggering the avalanche transistors; generating a high-voltage pulse from the charge stored in the capacitors; and recharging the capacitors through the charge resistors.

  8. Smallest Nanoelectronic with Atomic Devices with Precise Structures

    NASA Technical Reports Server (NTRS)

    Yamada, Toshishige

    2000-01-01

    Since its invention in 1948, the transistor has revolutionized our everyday life - transistor radios and TV's appeared in the early 1960s, personal computers came into widespread use in the mid-1980s, and cellular phones, laptops, and palm-sized organizers dominated the 1990s. The electronics revolution is based upon transistor miniaturization; smaller transistors are faster, and denser circuitry has more functionality. Transistors in current generation chips are 0.25 micron or 250 nanometers in size, and the electronics industry has completed development of 0.18 micron transistors which will enter production within the next few years. Industry researchers are now working to reduce transistor size down to 0.13 micron - a thousandth of the width of a human hair. However, studies indicate that the miniaturization of silicon transistors will soon reach its limit. For further progress in microelectronics, scientists have turned to nanotechnology to advance the science. Rather than continuing to miniaturize transistors to a point where they become unreliable, nanotechnology offers the new approach of building devices on the atomic scale [see sidebar]. One vision for the next generation of miniature electronics is atomic chain electronics, where devices are composed of atoms aligned on top of a substrate surface in a regular pattern. The Atomic Chain Electronics Project (ACEP) - part of the Semiconductor Device Modeling and Nanotechnology group, Integrated Product Team at the NAS Facility has been developing the theory of understanding atomic chain devices, and the author's patent for atomic chain electronics is now pending.

  9. The Quench Control of Water Estimates in Convergent Margin Magmas

    NASA Astrophysics Data System (ADS)

    Gavrilenko, M.; Krawczynski, M.; Ruprecht, P.

    2017-12-01

    Mineral-hosted glassy melt inclusions (MIs) have been used to quantify magma volatile contents for several decades. Despite the growing number of volatile studies utilizing MIs, it has not been tested whether there is a physical limit on how much dissolved volatiles a glassy MI can contain. We explored the limits of MIs as hydrous magma recorders in an experimental study, showing that there is a limit of dissolved H2O that glassy MIs cannot exceed. These results show there is potential bias in the glassy MI data set; they can only faithfully record pre-eruptive H2O contents in the upper-most part of the Earth's crust where H2O-solubility is low. The current MI database cannot be used to robustly estimate the full range of arc magmas and therefore assess volatile budgets in primitive or evolved compositions. Such magmas may contain much larger amounts of H2O than currently recognized and the diversity of magma evolutionary pathways in subduction zones is likely being significantly underappreciated.

  10. Sex Differences in Magical Ideation: A Community-Based Twin Study

    PubMed Central

    Karcher, Nicole R.; Slutske, Wendy S.; Kerns, John G.; Piasecki, Thomas M.; Martin, Nicholas G.

    2014-01-01

    Two questions regarding sex differences in magical ideation were investigated in this study: (1) whether there are mean level sex differences on the Magical Ideation Scale (MIS), and (2) whether there are quantitative and/or qualitative sex differences in the genetic contributions to variation on this scale. These questions were evaluated using data obtained from a large community sample of adult Australian twins (N=4,355) that included opposite-sex pairs. Participants completed a modified 15-item version of the MIS within a larger assessment battery. Women reported both higher means and variability on the MIS than men; this was also observed within families (in opposite-sex twin pairs). Biometric modeling indicated that the proportion of variation in MIS scores due to genetic influences (indicating quantitative sex differences) and the specific latent genetic contributions to this variation (indicating qualitative sex differences) were the same in men and women. These findings clarify the nature of sex differences in magical ideation and point to avenues for future research. PMID:24364500

  11. Electrical characterizations of MIS structures based on variable-gap n(p)-HgCdTe grown by MBE on Si(0 1 3) substrates

    NASA Astrophysics Data System (ADS)

    Voitsekhovskii, A. V.; Nesmelov, S. N.; Dzyadukh, S. M.; Varavin, V. S.; Dvoretskii, S. A.; Mikhailov, N. N.; Yakushev, M. V.; Sidorov, G. Yu.

    2017-12-01

    Metal-insulator-semiconductor (MIS) structures based on n(p)-Hg1-xCdxTe (x = 0.22-0.40) with near-surface variable-gap layers were grown by the molecular-beam epitaxy (MBE) technique on the Si (0 1 3) substrates. Electrical properties of MIS structures were investigated experimentally at various temperatures (9-77 K) and directions of voltage sweep. The ;narrow swing; technique was used to determine the spectra of fast surface states with the exception of hysteresis effects. It is established that the density of fast surface states at the MCT/Al2O3 interface at a minimum does not exceed 3 × 1010 eV-1 × cm-2. For MIS structures based on n-MCT/Si(0 1 3), the differential resistance of the space-charge region in strong inversion mode in the temperature range 50-90 K is limited by the Shockley-Read-Hall generation in the space-charge region.

  12. Decoding noises in HIV computational genotyping.

    PubMed

    Jia, MingRui; Shaw, Timothy; Zhang, Xing; Liu, Dong; Shen, Ye; Ezeamama, Amara E; Yang, Chunfu; Zhang, Ming

    2017-11-01

    Lack of a consistent and reliable genotyping system can critically impede HIV genomic research on pathogenesis, fitness, virulence, drug resistance, and genomic-based healthcare and treatment. At present, mis-genotyping, i.e., background noises in molecular genotyping, and its impact on epidemic surveillance is unknown. For the first time, we present a comprehensive assessment of HIV genotyping quality. HIV sequence data were retrieved from worldwide published records, and subjected to a systematic genotyping assessment pipeline. Results showed that mis-genotyped cases occurred at 4.6% globally, with some regional and high-risk population heterogeneities. Results also revealed a consistent mis-genotyping pattern in gp120 in all studied populations except the group of men who have sex with men. Our study also suggests novel virus diversities in the mis-genotyped cases. Finally, this study reemphasizes the importance of implementing a standardized genotyping pipeline to avoid genotyping disparity and to advance our understanding of virus evolution in various epidemiological settings. Copyright © 2017 Elsevier Inc. All rights reserved.

  13. Depth Perception of Surgeons in Minimally Invasive Surgery.

    PubMed

    Bogdanova, Rositsa; Boulanger, Pierre; Zheng, Bin

    2016-10-01

    Minimally invasive surgery (MIS) poses visual challenges to the surgeons. In MIS, binocular disparity is not freely available for surgeons, who are required to mentally rebuild the 3-dimensional (3D) patient anatomy from a limited number of monoscopic visual cues. The insufficient depth cues from the MIS environment could cause surgeons to misjudge spatial depth, which could lead to performance errors thus jeopardizing patient safety. In this article, we will first discuss the natural human depth perception by exploring the main depth cues available for surgeons in open procedures. Subsequently, we will reveal what depth cues are lost in MIS and how surgeons compensate for the incomplete depth presentation. Next, we will further expand our knowledge by exploring some of the available solutions for improving depth presentation to surgeons. Here we will review the innovative approaches (multiple 2D camera assembly, shadow introduction) and devices (3D monitors, head-mounted devices, and auto-stereoscopic monitors) for 3D image presentation from the past few years. © The Author(s) 2016.

  14. Unexpected weak seasonal climate in the western Mediterranean region during MIS 31, a high-insolation forced interglacial

    NASA Astrophysics Data System (ADS)

    Oliveira, Dulce; Sánchez Goñi, Maria Fernanda; Naughton, Filipa; Polanco-Martínez, J. M.; Jimenez-Espejo, Francisco J.; Grimalt, Joan O.; Martrat, Belen; Voelker, Antje H. L.; Trigo, Ricardo; Hodell, David; Abrantes, Fátima; Desprat, Stéphanie

    2017-04-01

    Marine Isotope Stage 31 (MIS 31) is an important analogue for ongoing and projected global warming, yet key questions remain about the regional signature of its extreme orbital forcing and intra-interglacial variability. Based on a new direct land-sea comparison in SW Iberian margin IODP Site U1385 we examine the climatic variability between 1100 and 1050 ka including the ;super interglacial; MIS 31, a period dominated by the 41-ky obliquity periodicity. Pollen and biomarker analyses at centennial-scale-resolution provide new insights into the regional vegetation, precipitation regime and atmospheric and oceanic temperature variability on orbital and suborbital timescales. Our study reveals that atmospheric and SST warmth during MIS 31 was not exceptional in this region highly sensitive to precession. Unexpectedly, this warm stage stands out as a prolonged interval of a temperate and humid climate regime with reduced seasonality, despite the high insolation (precession minima values) forcing. We find that the dominant forcing on the long-term temperate forest development was obliquity, which may have induced a decrease in summer dryness and associated reduction in seasonal precipitation contrast. Moreover, this study provides the first evidence for persistent atmospheric millennial-scale variability during this interval with multiple forest decline events reflecting repeated cooling and drying episodes in SW Iberia. Our direct land-sea comparison shows that the expression of the suborbital cooling events on SW Iberian ecosystems is modulated by the predominance of high or low-latitude forcing depending on the glacial/interglacial baseline climate states. Severe dryness and air-sea cooling is detected under the larger ice volume during glacial MIS 32 and MIS 30. The extreme episodes, which in their climatic imprint are similar to the Heinrich events, are likely related to northern latitude ice-sheet instability and a disruption of the Atlantic Meridional Overturning Circulation (AMOC). In contrast, forest declines during MIS 31 are associated to neither SST cooling nor high-latitude freshwater forcing. Time-series analysis reveals a dominant cyclicity of about 6 ky in the temperate forest record, which points to a potential link with the fourth harmonic of precession and thus low-latitude insolation forcing.

  15. Final validation of the ProMisE molecular classifier for endometrial carcinoma in a large population-based case series.

    PubMed

    Kommoss, S; McConechy, M K; Kommoss, F; Leung, S; Bunz, A; Magrill, J; Britton, H; Kommoss, F; Grevenkamp, F; Karnezis, A; Yang, W; Lum, A; Krämer, B; Taran, F; Staebler, A; Lax, S; Brucker, S Y; Huntsman, D G; Gilks, C B; McAlpine, J N; Talhouk, A

    2018-05-01

    We have previously developed and confirmed a pragmatic molecular classifier for endometrial cancers; ProMisE (Proactive Molecular Risk Classifier for Endometrial Cancer). Inspired by the Cancer Genome Atlas, ProMisE identifies four prognostically distinct molecular subtypes and can be applied to diagnostic specimens (biopsy/curettings) enabling earlier informed decision-making. We have strictly adhered to the Institute of Medicine (IOM) guidelines for the development of genomic biomarkers, and herein present the final validation step of a locked-down classifier before clinical application. We assessed a retrospective cohort of women from the Tübingen University Women's Hospital treated for endometrial carcinoma between 2003 and 2013. Primary outcomes of overall, disease-specific, and progression-free survival were evaluated for clinical, pathological, and molecular features. Complete clinical and molecular data were evaluable from 452 women. Patient age ranged from 29 to 93 (median 65) years, and 87.8% cases were endometrioid histotype. Grade distribution included 282 (62.4%) G1, 75 (16.6%) G2, and 95 (21.0%) G3 tumors. 276 (61.1%) patients had stage IA disease, with the remaining stage IB [89 (19.7%)], stage II [26 (5.8%)], and stage III/IV [61 (13.5%)]. ProMisE molecular classification yielded 127 (28.1%) MMR-D, 42 (9.3%) POLE, 55 (12.2%) p53abn, and 228 (50.4%) p53wt. ProMisE was a prognostic marker for progression-free (P = 0.001) and disease-specific (P = 0.03) survival even after adjusting for known risk factors. Concordance between diagnostic and surgical specimens was highly favorable; accuracy 0.91, κ 0.88. We have developed, confirmed, and now validated a pragmatic molecular classification tool (ProMisE) that provides consistent categorization of tumors and identifies four distinct prognostic molecular subtypes. ProMisE can be applied to diagnostic samples and thus could be used to inform surgical procedure(s) and/or need for adjuvant therapy. Based on the IOM guidelines this classifier is now ready for clinical evaluation through prospective clinical trials.

  16. Depositional and sea-level history from MIS 6 (Termination II) to MIS 3 on the southern continental shelf of South Africa

    NASA Astrophysics Data System (ADS)

    Cawthra, H. C.; Jacobs, Z.; Compton, J. S.; Fisher, E. C.; Karkanas, P.; Marean, C. W.

    2018-02-01

    Pleistocene shoreline deposits comprised of calcified shallow marine (palaeobeach) and aeolian (palaeodune) facies found along mid-latitude coastlines can be useful indicators of past sea levels. Here, we describe a succession of such deposits that are presently exposed both above (subaerial) and below (submerged) mean sea level along the southern Cape coast of South Africa, 18 km east of the town of Mossel Bay. The submerged units provide a window on Late Pleistocene coastal processes, as palaeoshoreline deposits in this study extend to water depths of up to 55 m on the mid-shelf. Five sedimentary facies were identified in the strata and were compared to modern depositional environments of the local littoral zone, which include aeolian dune, upper shoreface, foreshore, intertidal swash and back-barrier settings. Twenty-two geological units were observed and mapped. Some of these units were directly dated with optically stimulated luminescence (OSL) dating. OSL ages were obtained for ten samples from the subaerial and twelve samples from the submerged deposits. Those geological units not directly dated were interpreted based on sedimentology and field/stratigraphic relationships to dated units. The stratigraphy and chronology of the succession indicates a record of initial deposition during Termination II (T-II) meltwater events, preceding and leading to marine isotope stage (MIS) 5e. Indicators for multiple sea-level fluctuations between MIS 5d and MIS 4, and sediment deposition at the end of MIS 4 and start of MIS 3 are also found. Both regressive and transgressive depositional cycles are well-preserved in the succession. We propose that palaeodune and palaeobeach deposits along the South Coast of South Africa have no clear preference for deposition during sea-level transgressions or regressions. Sediment deposition more closely mirrors the rate of sea level change, with deposition and preservation either during times of rapid sea-level movement, or oscillation around still-stand events. Periods of relatively slow average rise or fall of sea level are represented by erosional planation surfaces in this record.

  17. Differentiation of MIS 9 and MIS 11 in the continental record: vegetational, faunal, aminostratigraphic and sea-level evidence from coastal sites in Essex, UK

    NASA Astrophysics Data System (ADS)

    Roe, Helen M.; Coope, G. Russell; Devoy, Robert J. N.; Harrison, Colin J. O.; Penkman, Kirsty E. H.; Preece, Richard C.; Schreve, Danielle C.

    2009-11-01

    Multidisciplinary investigations of the vegetational, faunal and sea-level history inferred from the infills of buried channels on the coast of eastern Essex have a direct bearing on the differentiation of MIS 11 and MIS 9 in continental records. New data are presented from Cudmore Grove, an important site on Mersea Island that can be linked to the terrace sequence of the River Thames. The vegetational history has been reconstructed from a pollen sequence covering much of the interglacial represented. The temperate nature of the climate is apparent from a range of fossil groups, including plant remains, vertebrates (especially the rich herpetofauna), molluscs and beetles, which all have strong thermophilous components. The beetle data have been used to derive a Mutual Climatic Range reconstruction, suggesting that mean July temperatures were about 2 °C warmer than modern values for southeast England, whereas mean January temperatures may have been slightly colder. The sea-level history has been reconstructed from the molluscs, ostracods and especially the diatoms, which indicate that the marine transgression occurred considerably earlier in the interglacial cycle than at the neighbouring Hoxnian site at Clacton. There are a number of palynological similarities between the sequence at Cudmore Grove and Clacton, especially the presence of Abies and the occurrence of Azolla filiculoides megaspores. Moreover, both sites have yielded Palaeolithic archaeology, indeed the latter is the type site of the Clactonian (flake-and-core) industry. However, the sites can be differentiated on the basis of mammalian biostratigraphy, new aminostratigraphic data, as well as the differences in the sea-level history. The combined evidence suggests that the infill of the channel at Cudmore Grove accumulated during MIS 9, whereas the deposits at Clacton formed during MIS 11. The infill of a much later channel, yielding non-marine molluscs and vertebrates including Hippopotamus, appears to have formed during the Ipswichian (MIS 5e). This evidence is compared with other important sites of late Middle Pleistocene age in Britain and elsewhere on the continent and the importance of a multidisciplinary approach is stressed.

  18. Paleoclimatic and paleoceanographic records through Marine Isotope Stage 19 at the Chiba composite section, central Japan: A key reference for the Early-Middle Pleistocene Subseries boundary

    NASA Astrophysics Data System (ADS)

    Suganuma, Yusuke; Haneda, Yuki; Kameo, Koji; Kubota, Yoshimi; Hayashi, Hiroki; Itaki, Takuya; Okuda, Masaaki; Head, Martin, J.; Sugaya, Manami; Nakazato, Hiroomi; Igarashi, Atsuo; Shikoku, Kizuku; Hongo, Misao; Watanabe, Masami; Satoguchi, Yasufumi; Takeshita, Yoshihiro; Nishida, Naohisa; Izumi, Kentaro; Kawamura, Kenji; Kawamata, Moto; Okuno, Jun'ichi; Yoshida, Takeshi; Ogitsu, Itaru; Yabusaki, Hisashi; Okada, Makoto

    2018-07-01

    Marine Isotope Stage (MIS) 19 is an important analogue for the present interglacial because of its similar orbital configuration, especially the phasing of the obliquity maximum to precession minimum. However, sedimentary records suitable for capturing both terrestrial and marine environmental changes are limited, and thus the climatic forcing mechanisms for MIS 19 are still largely unknown. The Chiba composite section, east-central Japanese archipelago, is a continuous and expanded marine sedimentary succession well suited to capture terrestrial and marine environmental changes through MIS 19. In this study, a detailed oxygen isotope chronology is established from late MIS 20 to early MIS 18, supported by a U-Pb zircon age and the presence of the Matuyama-Brunhes boundary. New pollen, marine microfossil, and planktonic foraminiferal δ18O and Mg/Ca paleotemperature records reveal the complex interplay of climatic influences. Our pollen data suggest that the duration of full interglacial conditions during MIS 19 extends from 785.0 to 775.1 ka (9.9 kyr), which offers an important natural baseline in predicting the duration of the present interglacial. A Younger Dryas-type cooling event is present during Termination IX, suggesting that such events are linked to this orbital configuration. Millennial- to multi-millennial-scale variations in our δ18O and Mg/Ca records imply that the Subarctic Front fluctuated in the northwestern Pacific Ocean during late MIS 19, probably in response to East Asian winter monsoon variability. The climatic setting at this time appears to be related to less severe summer insolation minima at 65˚N and/or high winter insolation at 50˚N. Our records do not support a recently hypothesized direct coupling between variations in the geomagnetic field intensity and global/regional climate change. Our highly resolved paleoclimatic and paleoceanographic records, coupled with a well-defined Matuyama-Brunhes boundary (772.9 ka; duration 1.9 kyr), establish the Chiba composite section as an exceptional climatic and chronological reference section for the Early-Middle Pleistocene boundary.

  19. Differentiation of MIS 9 and MIS 11 in the continental record: vegetational, faunal, aminostratigraphic and sea-level evidence from coastal sites in Essex, UK

    PubMed Central

    Roe, Helen M.; Coope, G. Russell; Devoy, Robert J.N.; Harrison, Colin J.O.; Penkman, Kirsty E.H.; Preece, Richard C.; Schreve, Danielle C.

    2009-01-01

    Multidisciplinary investigations of the vegetational, faunal and sea-level history inferred from the infills of buried channels on the coast of eastern Essex have a direct bearing on the differentiation of MIS 11 and MIS 9 in continental records. New data are presented from Cudmore Grove, an important site on Mersea Island that can be linked to the terrace sequence of the River Thames. The vegetational history has been reconstructed from a pollen sequence covering much of the interglacial represented. The temperate nature of the climate is apparent from a range of fossil groups, including plant remains, vertebrates (especially the rich herpetofauna), molluscs and beetles, which all have strong thermophilous components. The beetle data have been used to derive a Mutual Climatic Range reconstruction, suggesting that mean July temperatures were about 2 °C warmer than modern values for southeast England, whereas mean January temperatures may have been slightly colder. The sea-level history has been reconstructed from the molluscs, ostracods and especially the diatoms, which indicate that the marine transgression occurred considerably earlier in the interglacial cycle than at the neighbouring Hoxnian site at Clacton. There are a number of palynological similarities between the sequence at Cudmore Grove and Clacton, especially the presence of Abies and the occurrence of Azolla filiculoides megaspores. Moreover, both sites have yielded Palaeolithic archaeology, indeed the latter is the type site of the Clactonian (flake-and-core) industry. However, the sites can be differentiated on the basis of mammalian biostratigraphy, new aminostratigraphic data, as well as the differences in the sea-level history. The combined evidence suggests that the infill of the channel at Cudmore Grove accumulated during MIS 9, whereas the deposits at Clacton formed during MIS 11. The infill of a much later channel, yielding non-marine molluscs and vertebrates including Hippopotamus, appears to have formed during the Ipswichian (MIS 5e). This evidence is compared with other important sites of late Middle Pleistocene age in Britain and elsewhere on the continent and the importance of a multidisciplinary approach is stressed. PMID:20119485

  20. Study on the Hydrogenated ZnO-Based Thin Film Transistors. Part 1

    DTIC Science & Technology

    2011-04-30

    IGZO film on the performance of thin film transistors 5 Chapter 2. Hydrogenation of a- IGZO channel layer in the thin film transistors 12...effect of substrate temperature during the deposition of a- IGZO film on the performance of thin film transistors Introduction The effect of substrate...temperature during depositing IGZO channel layer on the performance of amorphous indium-gallium-zinc oxide (a- IGZO

  1. p-Type Transparent Electronics

    DTIC Science & Technology

    2003-09-25

    thin - film transistors (TTFTs) reported to date in the literature are summarized. 2.2.1 Thin - Film Transistor Structure and Fabrication A TFT ...is incapable of controlling the TFT regardless of gate voltage, as described in Sec. 2.2.3.1. 2.2.4 Transparent Thin - Film Transistors (TTFTs...Transparent thin - film transistors (TTFTs) described in the literature to date are all n-channel devices. Several n-channel TTFTs (n-TTFTs) based on

  2. Theory and Device Modeling for Nano-Structured Transistor Channels

    DTIC Science & Technology

    2011-06-01

    zinc oxide ( ZnO ) thin film transistors ( TFTs ) that contain nanocrystalline grains on the order of ~20nm. The authors of ref. 1 present results...problem in order to determine the threshold voltage. 15. SUBJECT TERMS nano-structured transistor , mesoscopic, zinc oxide , ZnO , field-effect...and R. Neidhard, “Microwave ZnO Thin - Film Transistors ”, IEEE Electron Dev. Lett. 29, 1024 (2008); doi: 10.1109/LED.2008.2001635.

  3. High-Speed, high-power, switching transistor

    NASA Technical Reports Server (NTRS)

    Carnahan, D.; Ohu, C. K.; Hower, P. L.

    1979-01-01

    Silicon transistor rate for 200 angstroms at 400 to 600 volts combines switching speed of transistors with ruggedness, power capacity of thyristor. Transistor introduces unique combination of increased power-handling capability, unusally low saturation and switching losses, and submicrosecond switching speeds. Potential applications include high power switching regulators, linear amplifiers, chopper controls for high frequency electrical vehicle drives, VLF transmitters, RF induction heaters, kitchen cooking ranges, and electronic scalpels for medical surgery.

  4. AlGaSb Buffer Layers for Sb-Based Transistors

    DTIC Science & Technology

    2010-01-01

    transistor ( HEMT ), molecular beam epitaxy (MBE), field-effect transistor (FET), buffer layer INTRODUCTION High-electron-mobility transistors ( HEMTs ) with InAs...monolayers/s. The use of thinner buffer layers reduces molecular beam epitaxial growth time and source consumption. The buffer layers also exhibit...source. In addition, some of the flux from an Sb cell in a molecular beam epitaxy (MBE) system will deposit near the mouth of the cell, eventually

  5. Photonic transistor and router using a single quantum-dot-confined spin in a single-sided optical microcavity

    NASA Astrophysics Data System (ADS)

    Hu, C. Y.

    2017-03-01

    The future Internet is very likely the mixture of all-optical Internet with low power consumption and quantum Internet with absolute security guaranteed by the laws of quantum mechanics. Photons would be used for processing, routing and com-munication of data, and photonic transistor using a weak light to control a strong light is the core component as an optical analogue to the electronic transistor that forms the basis of modern electronics. In sharp contrast to previous all-optical tran-sistors which are all based on optical nonlinearities, here I introduce a novel design for a high-gain and high-speed (up to terahertz) photonic transistor and its counterpart in the quantum limit, i.e., single-photon transistor based on a linear optical effect: giant Faraday rotation induced by a single electronic spin in a single-sided optical microcavity. A single-photon or classical optical pulse as the gate sets the spin state via projective measurement and controls the polarization of a strong light to open/block the photonic channel. Due to the duality as quantum gate for quantum information processing and transistor for optical information processing, this versatile spin-cavity quantum transistor provides a solid-state platform ideal for all-optical networks and quantum networks.

  6. Photonic transistor and router using a single quantum-dot-confined spin in a single-sided optical microcavity

    PubMed Central

    Hu, C. Y.

    2017-01-01

    The future Internet is very likely the mixture of all-optical Internet with low power consumption and quantum Internet with absolute security guaranteed by the laws of quantum mechanics. Photons would be used for processing, routing and com-munication of data, and photonic transistor using a weak light to control a strong light is the core component as an optical analogue to the electronic transistor that forms the basis of modern electronics. In sharp contrast to previous all-optical tran-sistors which are all based on optical nonlinearities, here I introduce a novel design for a high-gain and high-speed (up to terahertz) photonic transistor and its counterpart in the quantum limit, i.e., single-photon transistor based on a linear optical effect: giant Faraday rotation induced by a single electronic spin in a single-sided optical microcavity. A single-photon or classical optical pulse as the gate sets the spin state via projective measurement and controls the polarization of a strong light to open/block the photonic channel. Due to the duality as quantum gate for quantum information processing and transistor for optical information processing, this versatile spin-cavity quantum transistor provides a solid-state platform ideal for all-optical networks and quantum networks. PMID:28349960

  7. Ferroelectric field-effect transistors based on solution-processed electrochemically exfoliated graphene

    NASA Astrophysics Data System (ADS)

    Heidler, Jonas; Yang, Sheng; Feng, Xinliang; Müllen, Klaus; Asadi, Kamal

    2018-06-01

    Memories based on graphene that could be mass produced using low-cost methods have not yet received much attention. Here we demonstrate graphene ferroelectric (dual-gate) field effect transistors. The graphene has been obtained using electrochemical exfoliation of graphite. Field-effect transistors are realized using a monolayer of graphene flakes deposited by the Langmuir-Blodgett protocol. Ferroelectric field effect transistor memories are realized using a random ferroelectric copolymer poly(vinylidenefluoride-co-trifluoroethylene) in a top gated geometry. The memory transistors reveal ambipolar behaviour with both electron and hole accumulation channels. We show that the non-ferroelectric bottom gate can be advantageously used to tune the on/off ratio.

  8. Complementary junction heterostructure field-effect transistor

    DOEpatents

    Baca, Albert G.; Drummond, Timothy J.; Robertson, Perry J.; Zipperian, Thomas E.

    1995-01-01

    A complimentary pair of compound semiconductor junction heterostructure field-effect transistors and a method for their manufacture are disclosed. The p-channel junction heterostructure field-effect transistor uses a strained layer to split the degeneracy of the valence band for a greatly improved hole mobility and speed. The n-channel device is formed by a compatible process after removing the strained layer. In this manner, both types of transistors may be independently optimized. Ion implantation is used to form the transistor active and isolation regions for both types of complimentary devices. The invention has uses for the development of low power, high-speed digital integrated circuits.

  9. Complementary junction heterostructure field-effect transistor

    DOEpatents

    Baca, A.G.; Drummond, T.J.; Robertson, P.J.; Zipperian, T.E.

    1995-12-26

    A complimentary pair of compound semiconductor junction heterostructure field-effect transistors and a method for their manufacture are disclosed. The p-channel junction heterostructure field-effect transistor uses a strained layer to split the degeneracy of the valence band for a greatly improved hole mobility and speed. The n-channel device is formed by a compatible process after removing the strained layer. In this manner, both types of transistors may be independently optimized. Ion implantation is used to form the transistor active and isolation regions for both types of complimentary devices. The invention has uses for the development of low power, high-speed digital integrated circuits. 10 figs.

  10. High-performance carbon nanotube thin-film transistors on flexible paper substrates

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Liu, Na; Yun, Ki Nam; Yu, Hyun-Yong

    Single-walled carbon nanotubes (SWCNTs) are promising materials as active channels for flexible transistors owing to their excellent electrical and mechanical properties. However, flexible SWCNT transistors have never been realized on paper substrates, which are widely used, inexpensive, and recyclable. In this study, we fabricated SWCNT thin-film transistors on photo paper substrates. The devices exhibited a high on/off current ratio of more than 10{sup 6} and a field-effect mobility of approximately 3 cm{sup 2}/V·s. The proof-of-concept demonstration indicates that SWCNT transistors on flexible paper substrates could be applied as low-cost and recyclable flexible electronics.

  11. Npn double heterostructure bipolar transistor with ingaasn base region

    DOEpatents

    Chang, Ping-Chih; Baca, Albert G.; Li, Nein-Yi; Hou, Hong Q.; Ashby, Carol I. H.

    2004-07-20

    An NPN double heterostructure bipolar transistor (DHBT) is disclosed with a base region comprising a layer of p-type-doped indium gallium arsenide nitride (InGaAsN) sandwiched between n-type-doped collector and emitter regions. The use of InGaAsN for the base region lowers the transistor turn-on voltage, V.sub.on, thereby reducing power dissipation within the device. The NPN transistor, which has applications for forming low-power electronic circuitry, is formed on a gallium arsenide (GaAs) substrate and can be fabricated at commercial GaAs foundries. Methods for fabricating the NPN transistor are also disclosed.

  12. Minimally Invasive Surgery (MIS) Approaches to Thoracolumbar Trauma.

    PubMed

    Kaye, Ian David; Passias, Peter

    2018-03-01

    Minimally invasive surgical (MIS) techniques offer promising improvements in the management of thoracolumbar trauma. Recent advances in MIS techniques and instrumentation for degenerative conditions have heralded a growing interest in employing these techniques for thoracolumbar trauma. Specifically, surgeons have applied these techniques to help manage flexion- and extension-distraction injuries, neurologically intact burst fractures, and cases of damage control. Minimally invasive surgical techniques offer a means to decrease blood loss, shorten operative time, reduce infection risk, and shorten hospital stays. Herein, we review thoracolumbar minimally invasive surgery with an emphasis on thoracolumbar trauma classification, minimally invasive spinal stabilization, surgical indications, patient outcomes, technical considerations, and potential complications.

  13. The chief information officer--capturing healthcare's rare bird.

    PubMed

    Krinsky, M L

    1986-08-01

    While we occasionally conducted MIS executive searches during the 1970s, the recent pace has quickened substantially. Healthcare corporations need the MIS executive or CIO to keep the organization technologically and managerially current. Downsizing of acute-care facilities, expansion of outpatient services and creation of new programs have put a premium on current, computer-generated data. Skilled managers must rely on an efficient, flexible data processing department to evaluate options and make decisions about corporate strategy and program development. A presentable, articulate, personable MIS executive is a key ingredient in a successful management team. The position will continue to grow in importance and prominence in the fast-changing healthcare delivery industry.

  14. Ultrashort Channel Length Black Phosphorus Field-Effect Transistors.

    PubMed

    Miao, Jinshui; Zhang, Suoming; Cai, Le; Scherr, Martin; Wang, Chuan

    2015-09-22

    This paper reports high-performance top-gated black phosphorus (BP) field-effect transistors with channel lengths down to 20 nm fabricated using a facile angle evaporation process. By controlling the evaporation angle, the channel length of the transistors can be reproducibly controlled to be anywhere between 20 and 70 nm. The as-fabricated 20 nm top-gated BP transistors exhibit respectable on-state current (174 μA/μm) and transconductance (70 μS/μm) at a VDS of 0.1 V. Due to the use of two-dimensional BP as the channel material, the transistors exhibit relatively small short channel effects, preserving a decent on-off current ratio of 10(2) even at an extremely small channel length of 20 nm. Additionally, unlike the unencapsulated BP devices, which are known to be chemically unstable in ambient conditions, the top-gated BP transistors passivated by the Al2O3 gate dielectric layer remain stable without noticeable degradation in device performance after being stored in ambient conditions for more than 1 week. This work demonstrates the great promise of atomically thin BP for applications in ultimately scaled transistors.

  15. Balancing Hole and Electron Conduction in Ambipolar Split-Gate Thin-Film Transistors.

    PubMed

    Yoo, Hocheon; Ghittorelli, Matteo; Lee, Dong-Kyu; Smits, Edsger C P; Gelinck, Gerwin H; Ahn, Hyungju; Lee, Han-Koo; Torricelli, Fabrizio; Kim, Jae-Joon

    2017-07-10

    Complementary organic electronics is a key enabling technology for the development of new applications including smart ubiquitous sensors, wearable electronics, and healthcare devices. High-performance, high-functionality and reliable complementary circuits require n- and p-type thin-film transistors with balanced characteristics. Recent advancements in ambipolar organic transistors in terms of semiconductor and device engineering demonstrate the great potential of this route but, unfortunately, the actual development of ambipolar organic complementary electronics is currently hampered by the uneven electron (n-type) and hole (p-type) conduction in ambipolar organic transistors. Here we show ambipolar organic thin-film transistors with balanced n-type and p-type operation. By manipulating air exposure and vacuum annealing conditions, we show that well-balanced electron and hole transport properties can be easily obtained. The method is used to control hole and electron conductions in split-gate transistors based on a solution-processed donor-acceptor semiconducting polymer. Complementary logic inverters with balanced charging and discharging characteristics are demonstrated. These findings may open up new opportunities for the rational design of complementary electronics based on ambipolar organic transistors.

  16. Management Information Systems, Planning, and Public Community Colleges.

    ERIC Educational Resources Information Center

    Ritch, Stephen W.; Munro, Robert J.

    Management Information Systems (MIS), originally developed in the areas of accounting, management science, and computer processing, are now being applied to decision-making in educational settings. Definitions of MIS are numerous and often vague, but management systems (as distinguished from other information systems) should promote real-time…

  17. Public Management Information Systems: Theory and Prescription.

    ERIC Educational Resources Information Center

    Bozeman, Barry; Bretschneider, Stuart

    1986-01-01

    The existing theoretical framework for research in management information systems (MIS) is criticized for its lack of attention to the external environment of organizations, and a new framework is developed which better accommodates MIS in public organizations: public management information systems. Four models of publicness that reflect external…

  18. Rationalizing Management Information System Costs.

    ERIC Educational Resources Information Center

    Parden, Robert J.

    This paper examines the proposition that management information systems (MIS) for colleges and universities are not achieving their original objectives of supporting better management decisions by providing more and better information in a more timely manner. As a consequence, the MIS activity should be reduced in scope, and standardized to…

  19. Language, Violence, and Indian Mis-education.

    ERIC Educational Resources Information Center

    Russell, Caskey

    2002-01-01

    Traces the history of institutionalized violence--both physical and symbolic--within American Indian education; the legacy of shame and guilt from the boarding school era, when oppression was internalized; and the relationship of such "mis-education" to the decline of Tlingit language and culture in southwestern Alaska. Discusses…

  20. The Graduate MIS Security Course: Objectives and Challenges

    ERIC Educational Resources Information Center

    Jensen, Bradley K.; Guynes, Carl S.; Nyaboga, Andrew

    2009-01-01

    Given the magnitude of real and potential losses, both private and public employers increasingly expect graduates of management information systems (MIS) programs to understand information security concepts. The infrastructure requirements for the course includes setting up a secure laboratory environment to accommodate the development of viruses…

  1. Recruitment of Hispanic Students into MIS Curricula

    ERIC Educational Resources Information Center

    McHaney, Roger; Martin, Dawne

    2007-01-01

    This paper provides several suggestions Hispanic student recruitment and retention in MIS or other business curricula. Cultural considerations like allocentrism and familialism are discussed along with the situation at K-State. It is believed that the recruitment and retention of Hispanic students can be influenced positively by considering…

  2. Insight to Marine Isotope Stage 13 using Late Pleistocene relaxation models of ice volume and carbon cycle change

    NASA Astrophysics Data System (ADS)

    Lisiecki, L. E.; Herrero, C.; García-Olivares, A.

    2016-12-01

    The Marine Isotope Stage (MIS) 13 interglacial is unusual in that warm Northern Hemisphere conditions were accompanied by relatively cool Southern Hemisphere conditions and because it was preceded by a mild glaciation (MIS 14) with less ice volume and higher CO2 levels than the two preceding glacial maxima. Here we investigate Late Pleistocene glacial cycles, and MIS 13 in particular, using two relaxation models from García-Olivares & Herrero [2013] that describe the relationships between global ice volume (V), atmospheric CO2 (C) and the extent of the Antarctic ice shelves (A). The two models differ in parameterizing deep ocean stratification as either a function of V and A (model 3τ) or as a function of C and A (model LS). Note that global ice volume, V, is most closely related to Northern hemisphere climate, whereas C and A are most closely related to Antarctic climate. Here we present the results of using a sea level stack [Spratt & Lisiecki, 2016] as the ice volume tuning target instead of benthic δ18O. We find that tuning to the sea level stack dramatically improves the simulation of MIS 13 in the 3τ model. With the sea level stack, 3τ correctly reproduces the weak amplitudes of MIS 13 and 14 and a double peak in CO2 during MIS 13, whereas the LS model does not reproduce these features using either tuning target. The first peak in CO2 follows a minor ice volume decrease at 530 kyr but significantly precedes a second, larger sea level rise at 500 kyr. The later sea level rise coincides with a second benthic δ18O decrease and likely triggered the second CO2 peak. This two-step transition to peak interglacial conditions might be caused by deep ocean stratification and Antarctic ice cover acting out of phase: weakened stratification produced an initial pulse of CO2 from the deep ocean, but because Antarctic warming was unusually weak, the Antarctic ice shelf remained relatively wide and less CO2 than usual was released from the deep ocean. Because ocean stratification in the 3τ model is affected by both hemispheres, hemispheric asymmetry during MIS 13 produced a less stable stratification that allowed for a second CO2 pulse. Thus, the unusual hemispheric asymmetry during MIS 13 allows us to identify the influences of both Northern and Southern hemisphere climate on deep ocean stratification and its role in regulating atmospheric CO2.

  3. Phytoplankton assemblages and (bio)geochemical proxies indicate enhanced productivity and sea-ice decline in the Ross Sea during Marine Isotope sub-Stage 5e

    NASA Astrophysics Data System (ADS)

    Hartman, Julian; Sangiorgi, Francesca; Albertazzi, Sonia; Ángeles Bárcena, Mariá; Bijl, Peter; Giglio, Federico; Langone, Leonardo; Peterse, Francien; Tateo, Fabio; Trincardi, Fabio; Asioli, Alessandra

    2017-04-01

    Sea ice is an important component of the Antarctic cryosphere. It plays an important role in climate (e.g. albedo, gas exchange with the atmosphere), ocean circulation and primary productivity. Although sea ice has been increasing on average around Antarctica as a result of current global climate change, long-term model predictions expect sea ice to decline. To better understand the changes in sea-ice cover and its consequences on the oceanography, biology and geochemistry of the Southern Ocean during on-going and near-future warming it is important to study past periods of global warming, such as the Last Interglacial (LIG, 125-119 ka), also known as Marine Isotope sub-Stage 5e (MIS5e). During MIS5e global temperatures were on average 2°C warmer than present-day, the same temperature set as maximum global warming limit during the recent Paris Agreement (COP21). We investigated changes in sea-ice cover and environmental conditions by means of diatom, palynological, foraminifer and (bio)geochemical data in a sediment core (AS05-10) from the continental slope of the Drygalski Basin, Ross Sea (2377 mbsl) encompassing the MIS5e. The core was collected within the frame of the PNRA 2009/A2.01 project, an Italian project with a multidisciplinary approach, and covers approximately the last 350 kyr according to an age model based on diatom bioevents and cyclostratigraphy. The productivity proxies, e.g., excess barium, magnetic susceptibility and diatom abundances show a strong relation to the glacial-interglacial cycles. The rapid deglaciations preceding MIS5e and MIS7e are characterized by Ice Rafted Debris and the presence of reworked material. Subsequently, each interglacial is characterized by enhanced productivity related to a decrease in annual sea-ice cover. The beginning of each interglacial is also marked by changes in the fossil assemblages and organic geochemical proxies indicative of high nutrient conditions and water column stratification due to fresh water discharge. Annual sea-ice cover was most reduced during MIS5e. Diatoms indicate that surface water conditions were much more open during MIS5e than during the other marine isotope stages. Furthermore, there was a brief period of reduced bottom water oxygenation during MIS5e, which has led to enhanced preservation of fossil organic material in the sediments. Possibly, this is caused by a reduced influence of oxygen-rich High Salinity Shelf Water due to freshening of the shelf waters.

  4. Effectiveness of Implementation of Electronic Malaria Information System as the National Malaria Surveillance System in Thailand

    PubMed Central

    2016-01-01

    Background In moving toward malaria elimination, one strategy is to implement an active surveillance system for effective case management. Thailand has developed and implemented the electronic Malaria Information System (eMIS) capturing individualized electronic records of suspected or confirmed malaria cases. Objective The main purpose of this study was to determine how well the eMIS improves the quality of Thailand’s malaria surveillance system. In particular, the focus of the study was to evaluate the effectiveness of the eMIS in terms of the system users’ perception and the system outcomes (ie, quality of data) regarding the management of malaria patients. Methods A mixed-methods technique was used with the framework based on system effectiveness attributes: data quality, timeliness, simplicity, acceptability, flexibility, stability, and usefulness. Three methods were utilized: data records review, survey of system users, and in-depth interviews with key stakeholders. From the two highest endemic provinces, paper forms matching electronic records of 4455 noninfected and 784 malaria-infected cases were reviewed. Web-based anonymous questionnaires were distributed to all 129 eMIS data entry staff throughout Thailand, and semistructured interviews were conducted with 12 management-level officers. Results The eMIS is well accepted by system users at both management and operational levels. The data quality has enabled malaria personnel to perform more effective prevention and control activities. There is evidence of practices resulting in inconsistencies and logical errors in data reporting. Critical data elements were mostly completed, except for a few related to certain dates and area classifications. Timeliness in reporting a case to the system was acceptable with a delay of 3-4 days. The evaluation of quantitative and qualitative data confirmed that the eMIS has high levels of simplicity, acceptability, stability, and flexibility. Conclusions Overall, the system implemented has achieved its objective. The results of the study suggested that the eMIS helps improve the quality of Thailand’s malaria surveillance system. As the national malaria surveillance system, the eMIS’s functionalities have provided the malaria staff working at the point of care with close-to-real-time case management data quality, covering case detection, case investigation, drug compliance, and follow-up visits. Such features has led to an improvement in the quality of the malaria control program; the government officials now have quicker access to both individual and aggregated data to promptly react to possible outbreak. The eMIS thus plays one of the key roles in moving toward the national goal of malaria elimination by the next decade. PMID:27227156

  5. Paleosols in low-order streams and valley heads in the Araucaria Plateau - Record of continental environmental conditions in southern Brazil at the end of MIS 3

    NASA Astrophysics Data System (ADS)

    Paisani, Julio Cesar; Pontelli, Marga Eliz; Osterrieth, Margarita Luisa; Paisani, Sani Daniela Lopes; Fachin, Andressa; Guerra, Simone; Oliveira, Leandro

    2014-10-01

    The Araucaria Plateau is a geomorphological unit that occupies approximately three-quarters of the terrain in the southern region of Brazil. The plateau displays different altitudinal levels (600 to <1400 m a.s.l.) that are locally recognized as remnants of planed surfaces (S8-S1). These surfaces are maintained by basic (S3-S8) and acidic (S1 and S2) volcanic flows from the Neocretaceous period of the Paraná Basin. The largest extent of this plateau is located in a humid subtropical climate zone. Colluvial, colluvial-alluvial, alluvial sediments and paleosols (Ab diagnostic horizons) occur predominantly in S2. The paleosols are located in low-hierarchical-order fossil valleys (first- to fourth-order in Strahler's stream classification) and valley heads, which are referred to as paleovalleys in this paper. We employed these paleosols as stratigraphic level markers of the pedogenesis of the regional Upper Quaternary and propose their importance as records of the paleoenvironmental conditions of the Araucaria Plateau in areas above 1200 m a.s.l. These paleosols were dated by 14C and show ages between 23.8 ± 0.05 kyr BP (28.06-29.08 kyr cal. BP) and 41.16 ± 0.48 kyr BP (44.13-45.58 kyr cal. BP). The calibrated ages are related to Marine Isotope Stage 3 (MIS 3), in which the last period of global warming occurred (approximately 60-25 kyr cal. BP). We integrated the morphological, pedogeochemical, clay fraction mineralogy, micromorphological and δC-13 analyses of five paleosols from S2 to verify the paleoenvironmental conditions of the Araucaria Plateau and its correspondence with the paleoclimatic phenomena that were identified on a global scale during MIS 3 in the Southern Hemisphere. We obtained the following conclusions: a) the properties of paleosols reflect pedological processes that are adjusted to the paleoenvironmental conditions at the end of MIS 3 and the transition to MIS 2 (Last Glacial Maximum); b) aplasmogenic partial acidolysis was the predominant pedogeochemical process during MIS 3; c) during this period, the water regime was sufficiently humid to develop hydromorphic horizons in the valley bottoms of the entire drainage network to the valley heads; d) regional change toward a drier hydric regime occurred in MIS 2, when erosion of the paleosols predominated; and e) in MIS 1 (current Holocene interglacial), burial of the paleosols and relief inversion occurred, which resulted in fossilization of the valleys.

  6. DOE Office of Scientific and Technical Information (OSTI.GOV)

    Wesnousky, Steven G.; Briggs, Richard W.; Caffee, Marc W.

    Deposits near Lamoille in the Ruby Mountains-East Humboldt Range of central Nevada and at Woodfords on the eastern edge of the Sierra Nevada each record two distinct glacial advances. In this paper, we compare independent assessments of terrestrial cosmogenic nuclide (TCN) surface exposure ages for glacial deposits that we have determined to those obtained by others at the two sites. At each site, TCN ages of boulders on moraines of the younger advance are between 15 and 30 ka and may be associated with marine oxygen isotope stage (MIS) 2. At Woodfords, TCN ages of boulders on the moraine ofmore » the older advance are younger than ~ 60 ka and possibly formed during MIS 4, whereas boulders on the correlative outwash surface show ages approaching 140 ka (~ MIS 6). The TCN ages of boulders on older glacial moraine at Woodfords thus appear to severely underestimate the true age of the glacial advance responsible for the deposit. The same is possibly true at Lamoille where clasts sampled from the moraine of the oldest advance have ages ranging between 20 and 40 ka with a single outlier age of ~ 80 ka. The underestimations are attributed to the degradation and denudation of older moraine crests. Noting that boulder ages on the older advances at each site overlap significantly with MIS 2. Finally, we speculate that erosion of the older moraines has been episodic, with a pulse of denudation accompanying the inception of MIS 2 glaciation.« less

  7. The national survey of health administration program graduates on management information systems education.

    PubMed

    Zalkind, D; Malec, B

    1988-01-01

    A national survey of alumni of AUPHA programs from the classes of 1983, 1984, and 1985 was undertaken to assess their experiences in management information systems education, both formally and on the job. The survey covered 38 AUPHA graduate member programs and resulted in 1,181 responses. Over 40 percent of the alumni indicated that they had had an introductory management information systems (MIS) course in a health administration program. Since graduation, almost 90 percent have had some significant on-the-job involvement with computers, computer-generated information, or MIS. More than one-third of the respondents felt that their MIS course work did not adequately prepare them for what was expected on the job. Alumni stressed that microcomputer software applications, such as spreadsheets and data bases, are important areas for student hands-on experiences. When asked the importance of certain areas to be included in a required introductory MIS course, the alumni also recommended spreadsheet analysis and design, report writing and data presentation, and other management areas. Additional comments suggested more access to personal computers (PCs), more relevance in the curriculum to the "real world," and the importance of MIS to the career paths of alumni. Faculty suggestions from a 1984-85 survey are compared with alumni responses in order to identify curricular changes needed. Recommendations are outlined for consideration.

  8. Best-Matched Internal Standard Normalization in Liquid Chromatography-Mass Spectrometry Metabolomics Applied to Environmental Samples.

    PubMed

    Boysen, Angela K; Heal, Katherine R; Carlson, Laura T; Ingalls, Anitra E

    2018-01-16

    The goal of metabolomics is to measure the entire range of small organic molecules in biological samples. In liquid chromatography-mass spectrometry-based metabolomics, formidable analytical challenges remain in removing the nonbiological factors that affect chromatographic peak areas. These factors include sample matrix-induced ion suppression, chromatographic quality, and analytical drift. The combination of these factors is referred to as obscuring variation. Some metabolomics samples can exhibit intense obscuring variation due to matrix-induced ion suppression, rendering large amounts of data unreliable and difficult to interpret. Existing normalization techniques have limited applicability to these sample types. Here we present a data normalization method to minimize the effects of obscuring variation. We normalize peak areas using a batch-specific normalization process, which matches measured metabolites with isotope-labeled internal standards that behave similarly during the analysis. This method, called best-matched internal standard (B-MIS) normalization, can be applied to targeted or untargeted metabolomics data sets and yields relative concentrations. We evaluate and demonstrate the utility of B-MIS normalization using marine environmental samples and laboratory grown cultures of phytoplankton. In untargeted analyses, B-MIS normalization allowed for inclusion of mass features in downstream analyses that would have been considered unreliable without normalization due to obscuring variation. B-MIS normalization for targeted or untargeted metabolomics is freely available at https://github.com/IngallsLabUW/B-MIS-normalization .

  9. Dermal changes in superficial basal cell carcinoma, melanoma in situ and actinic keratosis and their implications

    PubMed Central

    Kazlouskaya, Viktoryia; Malhotra, Saurabh; Navarro, Raquel; Wu, Karen Nguyen; Shvartsbeyn, Marianna; Shengli, Chen; Gui, Jiang; Elston, Dirk M.

    2018-01-01

    Background Basal cell carcinoma (BCC) has a characteristic stroma, but less is known about the dermal characteristics associated with melanoma in situ (MIS) and actinic keratosis (AK). Materials and methods Dermal changes were studied in 301 specimens of AK, BCC and MIS. Subsequently, blinded images of dermal changes from 90 randomly selected cases of those entities were used to assess the predictive value of the dermal changes. Agreement with the final diagnosis was calculated using kappa coefficient (κ). Results Fibromyxoid stroma was present in 82% of BCC cases; fibrous stroma was seen in 25% of BCC, 58% of MIS and 35.6% of AK specimens (p <0.05). A lichenoid inflammatory infiltrate was frequently associated with AK and a perifollicular infiltrate with periadnexal fibrosis with MIS. Blinded evaluation of images of the dermal changes associated with the tumors yielded the correct diagnosis in (54.4, 41.1 and 27.8%; average 41.2%) by the three appraisers. Coefficient of agreement in blinded imaged evaluation with the actual diagnosis was higher in the BCC and MIS compared with AK (κ = 0.37, p = 0.0001; κ = 0.2, p = 0.0005 and κ = −0.06, p = 0.84, respectively). Conclusion Dermal features may be helpful in predicting the correct diagnosis when tumor is not visible. PMID:24117926

  10. Electrical properties of MIS devices on CdZnTe/HgCdTe

    NASA Astrophysics Data System (ADS)

    Lee, Tae-Seok; Jeoung, Y. T.; Kim, Hyun Kyu; Kim, Jae Mook; Song, Jinhan; Ann, S. Y.; Lee, Ji Y.; Kim, Young Hun; Kim, Sun-Ung; Park, Mann-Jang; Lee, S. D.; Suh, Sang-Hee

    1998-10-01

    In this paper, we report the capacitance-voltage (C-V) properties of metal-insulator-semiconductor (MIS) devices on CdTe/HgCdTe by the metalorganic chemical vapor deposition (MOCVD) and CdZnTe/HgCdTe by thermal evaporation. In MOCVD, CdTe layers are directly grown on HgCdTe using the metal organic sources of DMCd and DiPTe. HgCdTe layers are converted to n-type and the carrier concentration, ND is low 1015 cm-3 after Hg-vacancy annealing at 260 degrees Celsius. In thermal evaporation, CdZnTe passivation layers were deposited on HgCdTe surfaces after the surfaces were etched with 0.5 - 2.0% bromine in methanol solution. To investigate the electrical properties of the MIS devices, the C-V measurement is conducted at 80 K and 1 MHz. C-V curve of MIS devices on CdTe/HgCdTe by MOCVD has shown nearly flat band condition and large hysteresis, which is inferred to result from many defects in CdTe layer induced during Hg-vacancy annealing process. A negative flat band voltage (VFB approximately equals -2 V) and a small hysteresis have been observed for MIS devices on CdZnTe/HgCdTe by thermal evaporation. It is inferred that the negative flat band voltage results from residual Te4+ on the surface after etching with bromine in methanol solution.

  11. TRANSISTOR HIGH VOLTAGE POWER SUPPLY

    DOEpatents

    Driver, G.E.

    1958-07-15

    High voltage, direct current power supplies are described for use with battery powered nuclear detection equipment. The particular advantages of the power supply described, are increased efficiency and reduced size and welght brought about by the use of transistors in the circuit. An important feature resides tn the employment of a pair of transistors in an alternatefiring oscillator circuit having a coupling transformer and other circuit components which are used for interconnecting the various electrodes of the transistors.

  12. Base drive circuit

    DOEpatents

    Lange, A.C.

    1995-04-04

    An improved base drive circuit having a level shifter for providing bistable input signals to a pair of non-linear delays. The non-linear delays provide gate control to a corresponding pair of field effect transistors through a corresponding pair of buffer components. The non-linear delays provide delayed turn-on for each of the field effect transistors while an associated pair of transistors shunt the non-linear delays during turn-off of the associated field effect transistor. 2 figures.

  13. Organic transistors manufactured using inkjet technology with subfemtoliter accuracy

    PubMed Central

    Sekitani, Tsuyoshi; Noguchi, Yoshiaki; Zschieschang, Ute; Klauk, Hagen; Someya, Takao

    2008-01-01

    A major obstacle to the development of organic transistors for large-area sensor, display, and circuit applications is the fundamental compromise between manufacturing efficiency, transistor performance, and power consumption. In the past, improving the manufacturing efficiency through the use of printing techniques has inevitably resulted in significantly lower performance and increased power consumption, while attempts to improve performance or reduce power have led to higher process temperatures and increased manufacturing cost. Here, we lift this fundamental limitation by demonstrating subfemtoliter inkjet printing to define metal contacts with single-micrometer resolution on the surface of high-mobility organic semiconductors to create high-performance p-channel and n-channel transistors and low-power complementary circuits. The transistors employ an ultrathin low-temperature gate dielectric based on a self-assembled monolayer that allows transistors and circuits on rigid and flexible substrates to operate with very low voltages. PMID:18362348

  14. Comparative studies of Ge and Si p-channel metal-oxide-semiconductor field-effect-transistors with HfSiON dielectric and TaN metal gate

    NASA Astrophysics Data System (ADS)

    Hu, Ai-Bin; Xu, Qiu-Xia

    2010-05-01

    Ge and Si p-channel metal-oxide-semiconductor field-effect-transistors (p-MOSFETs) with hafnium silicon oxynitride (HfSiON) gate dielectric and tantalum nitride (TaN) metal gate are fabricated. Self-isolated ring-type transistor structures with two masks are employed. W/TaN metal stacks are used as gate electrode and shadow masks of source/drain implantation separately. Capacitance-voltage curve hysteresis of Ge metal-oxide-semiconductor (MOS) capacitors may be caused by charge trapping centres in GeO2 (1 < x < 2). Effective hole mobilities of Ge and Si transistors are extracted by using a channel conductance method. The peak hole mobilities of Si and Ge transistors are 33.4 cm2/(V · s) and 81.0 cm2/(V · s), respectively. Ge transistor has a hole mobility 2.4 times higher than that of Si control sample.

  15. Back bias induced dynamic and steep subthreshold swing in junctionless transistors

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Parihar, Mukta Singh; Kranti, Abhinav, E-mail: akranti@iiti.ac.in

    In this work, we analyze back bias induced steep and dynamic subthreshold swing in junctionless double gate transistors operated in the asymmetric mode. This impact ionization induced dynamic subthreshold swing is explained in terms of the ratio between minimum hole concentration and peak electron concentration, and the dynamic change in the location of the conduction channel with applied front gate voltage. The reason for the occurrence of impact ionization at sub-bandgap drain voltages in silicon junctionless transistors is also accounted for. The optimum junctionless transistor operating at a back gate bias of −0.9 V, achieves over 5 orders of change inmore » drain current at a gate overdrive of 200 mV and drain bias of 1 V. These results for junctionless transistors are significantly better than those exhibited by silicon tunnel field effect transistors operating at the same drain bias.« less

  16. I-V Characteristics of a Ferroelectric Field Effect Transistor

    NASA Technical Reports Server (NTRS)

    MacLeod, Todd C.; Ho, Fat Duen

    1999-01-01

    There are many possible uses for ferroelectric field effect transistors.To understand their application, a fundamental knowledge of their basic characteristics must first be found. In this research, the current and voltage characteristics of a field effect transistor are described. The effective gate capacitance and charge are derived from experimental data on an actual FFET. The general equation for a MOSFET is used to derive the internal characteristics of the transistor: This equation is modified slightly to describe the FFET characteristics. Experimental data derived from a Radiant Technologies FFET is used to calculate the internal transistor characteristics using fundamental MOSFET equations. The drain current was measured under several different gate and drain voltages and with different initial polarizations on the ferroelectric material in the transistor. Two different polarization conditions were used. One with the gate ferroelectric material polarized with a +9.0 volt write pulse and one with a -9.0 volt pulse.

  17. A Novel Metal-Ferroelectric-Semiconductor Field-Effect Transistor Memory Cell Design

    NASA Technical Reports Server (NTRS)

    Phillips, Thomas A.; Bailey, Mark; Ho, Fat Duen

    2004-01-01

    The use of a Metal-Ferroelectric-Semiconductor Field-Effect Transistor (MFSFET) in a resistive-load SRAM memory cell has been investigated A typical two-transistor resistive-load SRAM memory cell architecture is modified by replacing one of the NMOS transistors with an n-channel MFSFET. The gate of the MFSFET is connected to a polling voltage pulse instead of the other NMOS transistor drain. The polling voltage pulses are of sufficient magnitude to saturate the ferroelectric gate material and force the MFSFET into a particular logic state. The memory cell circuit is further modified by the addition of a PMOS transistor and a load resistor in order to improve the retention characteristics of the memory cell. The retention characteristics of both the "1" and "0" logic states are simulated. The simulations show that the MFSFET memory cell design can maintain both the "1" and "0" logic states for a long period of time.

  18. High-Performance Vertical Organic Electrochemical Transistors.

    PubMed

    Donahue, Mary J; Williamson, Adam; Strakosas, Xenofon; Friedlein, Jacob T; McLeod, Robert R; Gleskova, Helena; Malliaras, George G

    2018-02-01

    Organic electrochemical transistors (OECTs) are promising transducers for biointerfacing due to their high transconductance, biocompatibility, and availability in a variety of form factors. Most OECTs reported to date, however, utilize rather large channels, limiting the transistor performance and resulting in a low transistor density. This is typically a consequence of limitations associated with traditional fabrication methods and with 2D substrates. Here, the fabrication and characterization of OECTs with vertically stacked contacts, which overcome these limitations, is reported. The resulting vertical transistors exhibit a reduced footprint, increased intrinsic transconductance of up to 57 mS, and a geometry-normalized transconductance of 814 S m -1 . The fabrication process is straightforward and compatible with sensitive organic materials, and allows exceptional control over the transistor channel length. This novel 3D fabrication method is particularly suited for applications where high density is needed, such as in implantable devices. © 2017 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  19. Depletion type floating gate p-channel MOS transistor for recording action potentials generated by cultured neurons.

    PubMed

    Cohen, Ariel; Spira, Micha E; Yitshaik, Shlomo; Borghs, Gustaaf; Shwartzglass, Ofer; Shappir, Joseph

    2004-07-15

    We report the realization of electrical coupling between neurons and depletion type floating gate (FG) p-channel MOS transistors. The devices were realized in a shortened 0.5 microm CMOS technology. Increased boron implant dose was used to form the depletion type devices. Post-CMOS processing steps were added to expose the devices sensing area. The neurons are coupled to the polycrystalline silicon (PS) FG through 420A thermal oxide in an area which is located over the thick field oxide away from the transistor. The combination of coupling area pad having a diameter of 10 or 15 microm and sensing transistor with W/L of 50/0.5 microm results in capacitive coupling ratio of the neuron signal of about 0.5 together with relatively large transistor transconductance. The combination of the FG structure with a depletion type device, leads to the following advantages. (a) No need for dc bias between the solution in which the neurons are cultured and the transistor with expected consequences to the neuron as well as the silicon die durability. (b) The sensing area of the neuron activity is separated from the active area of the transistor. Thus, it is possible to design the sensing area and the channel area separately. (c) The channel area, which is the most sensitive part of the transistor, can be insulated and shielded from the ionic solution in which the neurons are cultured. (d) There is an option to add a switching transistor to the FG and use the FG also for the neuron stimulation.

  20. Modeling of charge transport in ion bipolar junction transistors.

    PubMed

    Volkov, Anton V; Tybrandt, Klas; Berggren, Magnus; Zozoulenko, Igor V

    2014-06-17

    Spatiotemporal control of the complex chemical microenvironment is of great importance to many fields within life science. One way to facilitate such control is to construct delivery circuits, comprising arrays of dispensing outlets, for ions and charged biomolecules based on ionic transistors. This allows for addressability of ionic signals, which opens up for spatiotemporally controlled delivery in a highly complex manner. One class of ionic transistors, the ion bipolar junction transistors (IBJTs), is especially attractive for these applications because these transistors are functional at physiological conditions and have been employed to modulate the delivery of neurotransmitters to regulate signaling in neuronal cells. Further, the first integrated complementary ionic circuits were recently developed on the basis of these ionic transistors. However, a detailed understanding of the device physics of these transistors is still lacking and hampers further development of components and circuits. Here, we report on the modeling of IBJTs using Poisson's and Nernst-Planck equations and the finite element method. A two-dimensional model of the device is employed that successfully reproduces the main characteristics of the measurement data. On the basis of the detailed concentration and potential profiles provided by the model, the different modes of operation of the transistor are analyzed as well as the transitions between the different modes. The model correctly predicts the measured threshold voltage, which is explained in terms of membrane potentials. All in all, the results provide the basis for a detailed understanding of IBJT operation. This new knowledge is employed to discuss potential improvements of ion bipolar junction transistors in terms of miniaturization and device parameters.

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