Bi-Frequency Modulated Quasi-Resonant Converters: Theory and Applications

NASA Astrophysics Data System (ADS)

Zhang, Yuefeng

1995-01-01

To avoid the variable frequency operation of quasi -resonant converters, many soft-switching PWM converters have been proposed, all of them require an auxiliary switch, which will increase the cost and complexity of the power supply system. In this thesis, a new kind of technique for quasi -resonant converters has been proposed, which is called the bi-frequency modulation technique. By operating the quasi-resonant converters at two switching frequencies, this technique enables quasi-resonant converters to achieve the soft-switching, at fixed switching frequencies, without an auxiliary switch. The steady-state analysis of four commonly used quasi-resonant converters, namely, ZVS buck, ZCS buck, ZVS boost, and ZCS boost converter has been presented. Using the concepts of equivalent sources, equivalent sinks, and resonant tank, the large signal models of these four quasi -resonant converters were developed. Based on these models, the steady-state control characteristics of BFM ZVS buck, BFM ZCS buck, BFM ZVS boost, and BFM ZCS boost converter have been derived. The functional block and design consideration of the bi-frequency controller were presented, and one of the implementations of the bi-frequency controller was given. A complete design example has been presented. Both computer simulations and experimental results have verified that the bi-frequency modulated quasi-resonant converters can achieve soft-switching, at fixed switching frequencies, without an auxiliary switch. One of the application of bi-frequency modulation technique is for EMI reduction. The basic principle of using BFM technique for EMI reduction was introduced. Based on the spectral analysis, the EMI performances of the PWM, variable-frequency, and bi-frequency modulated control signals was evaluated, and the BFM control signals show the lowest EMI emission. The bi-frequency modulated technique has also been applied to the power factor correction. A BFM zero -current switching boost converter has been designed for the power factor correction, and the simulation results show that the power factor has been improved.

Closed-loop analysis and control of a non-inverting buck-boost converter

NASA Astrophysics Data System (ADS)

Chen, Zengshi; Hu, Jiangang; Gao, Wenzhong

2010-11-01

In this article, a cascade controller is designed and analysed for a non-inverting buck-boost converter. The fast inner current loop uses sliding mode control. The slow outer voltage loop uses the proportional-integral (PI) control. Stability analysis and selection of PI gains are based on the nonlinear closed-loop error dynamics incorporating both the inner and outer loop controllers. The closed-loop system is proven to have a nonminimum phase structure. The voltage transient due to step changes of input voltage or resistance is predictable. The operating range of the reference voltage is discussed. The controller is validated by a simulation circuit. The simulation results show that the reference output voltage is well-tracked under system uncertainties or disturbances, confirming the validity of the proposed controller.

A Bidirectional High-Power-Quality Grid Interface With a Novel Bidirectional Noninverted Buck Boost Converter for PHEVs

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

Onar, Omer C

2012-01-01

Plug-in hybrid electric vehicles (PHEVs) will play a vital role in future sustainable transportation systems due to their potential in terms of energy security, decreased environmental impact, improved fuel economy, and better performance. Moreover, new regulations have been established to improve the collective gas mileage, cut greenhouse gas emissions, and reduce dependence on foreign oil. This paper primarily focuses on two major thrust areas of PHEVs. First, it introduces a grid-friendly bidirectional alternating current/direct current ac/dc dc/ac rectifier/inverter for facilitating vehicle-to-grid (V2G) integration of PHEVs. Second, it presents an integrated bidirectional noninverted buck boost converter that interfaces the energy storagemore » device of the PHEV to the dc link in both grid-connected and driving modes. The proposed bidirectional converter has minimal grid-level disruptions in terms of power factor and total harmonic distortion, with less switching noise. The integrated bidirectional dc/dc converter assists the grid interface converter to track the charge/discharge power of the PHEV battery. In addition, while driving, the dc/dc converter provides a regulated dc link voltage to the motor drive and captures the braking energy during regenerative braking.« less

Optimal design strategy of switching converters employing current injected control

NASA Astrophysics Data System (ADS)

Lee, F. C.; Fang, Z. D.; Lee, T. H.

1985-01-01

This paper analyzes a buck/boost regulator employing current-injected control (CIC). It reveals the complex interactions between the dc loop and the current-injected loop and underlines the fundamental principle that governs the loop gain determination. Three commonly used compensation techniques are compared. The integral and lead/lag compensation are shown to be most desirable for performance optimization and stability.

Mathematical simulation of power conditioning systems. Volume 1: Simulation of elementary units. Report on simulation methodology

NASA Technical Reports Server (NTRS)

Prajous, R.; Mazankine, J.; Ippolito, J. C.

1978-01-01

Methods and algorithms used for the simulation of elementary power conditioning units buck, boost, and buck-boost, as well as shunt PWM are described. Definitions are given of similar converters and reduced parameters. The various parts of the simulation to be carried out are dealt with; local stability, corrective network, measurements of input-output impedance and global stability. A simulation example is given.

User's design handbook for a Standardized Control Module (SCM) for DC to DC Converters, volume 2

NASA Technical Reports Server (NTRS)

Lee, F. C.

1980-01-01

A unified design procedure is presented for selecting the key SCM control parameters for an arbitrarily given power stage configuration and parameter values, such that all regulator performance specifications can be met and optimized concurrently in a single design attempt. All key results and performance indices, for buck, boost, and buck/boost switching regulators which are relevant to SCM design considerations are included to facilitate frequent references.

Modelling, analyses and design of switching converters

NASA Technical Reports Server (NTRS)

Cuk, S. M.; Middlebrook, R. D.

1978-01-01

A state-space averaging method for modelling switching dc-to-dc converters for both continuous and discontinuous conduction mode is developed. In each case the starting point is the unified state-space representation, and the end result is a complete linear circuit model, for each conduction mode, which correctly represents all essential features, namely, the input, output, and transfer properties (static dc as well as dynamic ac small-signal). While the method is generally applicable to any switching converter, it is extensively illustrated for the three common power stages (buck, boost, and buck-boost). The results for these converters are then easily tabulated owing to the fixed equivalent circuit topology of their canonical circuit model. The insights that emerge from the general state-space modelling approach lead to the design of new converter topologies through the study of generic properties of the cascade connection of basic buck and boost converters.

State-plane analysis of zero-voltage-switching resonant dc/dc power converters

NASA Astrophysics Data System (ADS)

Kazimierczuk, Marian K.; Morse, William D.

The state-plane analysis technique for the zero-voltage-switching resonant dc/dc power converter family of topologies, namely the buck, boost, buck-boost, and Cuk converters is established. The state plane provides a compression of information that allows the designer to uniquely examine the nonlinear dynamics of resonant converter operation. Utilizing the state plane, resonant converter modes of operation are examined and the switching frequencies are derived for the boundaries between these modes, including the boundary of energy conversion.

Modeling and analysis of fractional order DC-DC converter.

PubMed

Radwan, Ahmed G; Emira, Ahmed A; AbdelAty, Amr M; Azar, Ahmad Taher

2017-07-11

Due to the non-idealities of commercial inductors, the demand for a better model that accurately describe their dynamic response is elevated. So, the fractional order models of Buck, Boost and Buck-Boost DC-DC converters are presented in this paper. The detailed analysis is made for the two most common modes of converter operation: Continuous Conduction Mode (CCM) and Discontinuous Conduction Mode (DCM). Closed form time domain expressions are derived for inductor currents, voltage gain, average current, conduction time and power efficiency where the effect of the fractional order inductor is found to be strongly present. For example, the peak inductor current at steady state increases with decreasing the inductor order. Advanced Design Systems (ADS) circuit simulations are used to verify the derived formulas, where the fractional order inductor is simulated using Valsa Constant Phase Element (CPE) approximation and Generalized Impedance Converter (GIC). Different simulation results are introduced with good matching to the theoretical formulas for the three DC-DC converter topologies under different fractional orders. A comprehensive comparison with the recently published literature is presented to show the advantages and disadvantages of each approach. Copyright © 2017 ISA. Published by Elsevier Ltd. All rights reserved.

dc analysis and design of zero-voltage-switched multi-resonant converters

NASA Astrophysics Data System (ADS)

Tabisz, Wojciech A.; Lee, Fred C.

Recently introduced multiresonant converters (MRCs) provide zero-voltage switching (ZVS) of both active and passive switches and offer a substantial reduction of transistor voltage stress and an increase of load range, compared to their quasi-resonant converter counterparts. Using the resonant switch concept, a simple, generalized analysis of ZVS MRCs is presented. The conversion ratio and voltage stress characteristics are derived for basic ZVS MRCs, including buck, boost, and buck/boost converters. Based on the analysis, a design procedure that optimizes the selection of resonant elements for maximum conversion efficiency is proposed.

Two-inductor boost and buck converters

NASA Astrophysics Data System (ADS)

White, J. L.; Muldoon, W. J.

The derivation, analysis and design of a coupled inductor boost converter is presented. Aspects of the qualitative ac behavior of coupled inductor converters are discussed. Considerations for the design of the magnetics for such converters are addressed.

Transformerless dc-Isolated Converter

NASA Technical Reports Server (NTRS)

Rippel, Wally E.

1987-01-01

Efficient voltage converter employs capacitive instead of transformer coupling to provide dc isolation. Offers buck/boost operation, minimal filtering, and low parts count, with possible application in photovoltaic power inverters, power supplies and battery charges. In photovoltaic inverter circuit with transformerless converter, Q2, Q3, Q4, and Q5 form line-commutated inverter. Switching losses and stresses nil because switching performed when current is zero.

An Optimal Control Strategy for DC Bus Voltage Regulation in Photovoltaic System with Battery Energy Storage

PubMed Central

Daud, Muhamad Zalani; Mohamed, Azah; Hannan, M. A.

2014-01-01

This paper presents an evaluation of an optimal DC bus voltage regulation strategy for grid-connected photovoltaic (PV) system with battery energy storage (BES). The BES is connected to the PV system DC bus using a DC/DC buck-boost converter. The converter facilitates the BES power charge/discharge to compensate for the DC bus voltage deviation during severe disturbance conditions. In this way, the regulation of DC bus voltage of the PV/BES system can be enhanced as compared to the conventional regulation that is solely based on the voltage-sourced converter (VSC). For the grid side VSC (G-VSC), two control methods, namely, the voltage-mode and current-mode controls, are applied. For control parameter optimization, the simplex optimization technique is applied for the G-VSC voltage- and current-mode controls, including the BES DC/DC buck-boost converter controllers. A new set of optimized parameters are obtained for each of the power converters for comparison purposes. The PSCAD/EMTDC-based simulation case studies are presented to evaluate the performance of the proposed optimized control scheme in comparison to the conventional methods. PMID:24883374

An optimal control strategy for DC bus voltage regulation in photovoltaic system with battery energy storage.

PubMed

Daud, Muhamad Zalani; Mohamed, Azah; Hannan, M A

2014-01-01

This paper presents an evaluation of an optimal DC bus voltage regulation strategy for grid-connected photovoltaic (PV) system with battery energy storage (BES). The BES is connected to the PV system DC bus using a DC/DC buck-boost converter. The converter facilitates the BES power charge/discharge to compensate for the DC bus voltage deviation during severe disturbance conditions. In this way, the regulation of DC bus voltage of the PV/BES system can be enhanced as compared to the conventional regulation that is solely based on the voltage-sourced converter (VSC). For the grid side VSC (G-VSC), two control methods, namely, the voltage-mode and current-mode controls, are applied. For control parameter optimization, the simplex optimization technique is applied for the G-VSC voltage- and current-mode controls, including the BES DC/DC buck-boost converter controllers. A new set of optimized parameters are obtained for each of the power converters for comparison purposes. The PSCAD/EMTDC-based simulation case studies are presented to evaluate the performance of the proposed optimized control scheme in comparison to the conventional methods.

Derivation of linearized transfer functions for switching-mode regulations. Phase A: Current step-up and voltage step-up converters

NASA Technical Reports Server (NTRS)

Wong, R. C.; Owen, H. A., Jr.; Wilson, T. G.

1981-01-01

Small-signal models are derived for the power stage of the voltage step-up (boost) and the current step-up (buck) converters. The modeling covers operation in both the continuous-mmf mode and the discontinuous-mmf mode. The power stage in the regulated current step-up converter on board the Dynamics Explorer Satellite is used as an example to illustrate the procedures in obtaining the small-signal functions characterizing a regulated converter.

The Series Connected Buck Boost Regulator Concept for High Efficiency Light Weight DC Voltage Regulation

NASA Technical Reports Server (NTRS)

Birchenough, Arthur G.

2003-01-01

Improvements in the efficiency and size of DC-DC converters have resulted from advances in components, primarily semiconductors, and improved topologies. One topology, which has shown very high potential in limited applications, is the Series Connected Boost Unit (SCBU), wherein a small DC-DC converter output is connected in series with the input bus to provide an output voltage equal to or greater than the input voltage. Since the DC-DC converter switches only a fraction of the power throughput, the overall system efficiency is very high. But this technique is limited to applications where the output is always greater than the input. The Series Connected Buck Boost Regulator (SCBBR) concept extends partial power processing technique used in the SCBU to operation when the desired output voltage is higher or lower than the input voltage, and the implementation described can even operate as a conventional buck converter to operate at very low output to input voltage ratios. This paper describes the operation and performance of an SCBBR configured as a bus voltage regulator providing 50 percent voltage regulation range, bus switching, and overload limiting, operating above 98 percent efficiency. The technique does not provide input-output isolation.

Bidirectional buck boost converter

DOEpatents

Esser, Albert Andreas Maria

1998-03-31

A bidirectional buck boost converter and method of operating the same allows regulation of power flow between first and second voltage sources in which the voltage level at each source is subject to change and power flow is independent of relative voltage levels. In one embodiment, the converter is designed for hard switching while another embodiment implements soft switching of the switching devices. In both embodiments, first and second switching devices are serially coupled between a relatively positive terminal and a relatively negative terminal of a first voltage source with third and fourth switching devices serially coupled between a relatively positive terminal and a relatively negative terminal of a second voltage source. A free-wheeling diode is coupled, respectively, in parallel opposition with respective ones of the switching devices. An inductor is coupled between a junction of the first and second switching devices and a junction of the third and fourth switching devices. Gating pulses supplied by a gating circuit selectively enable operation of the switching devices for transferring power between the voltage sources. In the second embodiment, each switching device is shunted by a capacitor and the switching devices are operated when voltage across the device is substantially zero.

Bidirectional buck boost converter

DOEpatents

Esser, A.A.M.

1998-03-31

A bidirectional buck boost converter and method of operating the same allows regulation of power flow between first and second voltage sources in which the voltage level at each source is subject to change and power flow is independent of relative voltage levels. In one embodiment, the converter is designed for hard switching while another embodiment implements soft switching of the switching devices. In both embodiments, first and second switching devices are serially coupled between a relatively positive terminal and a relatively negative terminal of a first voltage source with third and fourth switching devices serially coupled between a relatively positive terminal and a relatively negative terminal of a second voltage source. A free-wheeling diode is coupled, respectively, in parallel opposition with respective ones of the switching devices. An inductor is coupled between a junction of the first and second switching devices and a junction of the third and fourth switching devices. Gating pulses supplied by a gating circuit selectively enable operation of the switching devices for transferring power between the voltage sources. In the second embodiment, each switching device is shunted by a capacitor and the switching devices are operated when voltage across the device is substantially zero. 20 figs.

High-frequency high-voltage high-power DC-to-DC converters

NASA Technical Reports Server (NTRS)

Wilson, T. G.; Owen, H. A.; Wilson, P. M.

1982-01-01

A simple analysis of the current and voltage waveshapes associated with the power transistor and the power diode in an example current-or-voltage step-up (buck-boost) converter is presented. The purpose of the analysis is to provide an overview of the problems and design trade-offs which must be addressed as high-power high-voltage converters are operated at switching frequencies in the range of 100 kHz and beyond. Although the analysis focuses on the current-or-voltage step-up converter as the vehicle for discussion, the basic principles presented are applicable to other converter topologies as well.

High-frequency high-voltage high-power DC-to-DC converters

NASA Astrophysics Data System (ADS)

Wilson, T. G.; Owen, H. A.; Wilson, P. M.

1982-09-01

A simple analysis of the current and voltage waveshapes associated with the power transistor and the power diode in an example current-or-voltage step-up (buck-boost) converter is presented. The purpose of the analysis is to provide an overview of the problems and design trade-offs which must be addressed as high-power high-voltage converters are operated at switching frequencies in the range of 100 kHz and beyond. Although the analysis focuses on the current-or-voltage step-up converter as the vehicle for discussion, the basic principles presented are applicable to other converter topologies as well.

Monolithic quasi-sliding-mode controller for SIDO buck converter with a self-adaptive free-wheeling current level

NASA Astrophysics Data System (ADS)

Xiaobo, Wu; Qing, Liu; Menglian, Zhao; Mingyang, Chen

2013-01-01

An analog implementation of a novel fixed-frequency quasi-sliding-mode controller for single-inductor dual-output (SIDO) buck converter in pseudo-continuous conduction mode (PCCM) with a self-adaptive freewheeling current level (SFCL) is presented. Both small and large signal variations around the operation point are considered to achieve better transient response so as to reduce the cross-regulation of this SIDO buck converter. Moreover, an internal integral loop is added to suppress the steady-state regulation error introduced by conventional PWM-based sliding mode controllers. Instead of keeping it as a constant value, the free-wheeling current level varies according to the load condition to maintain high power efficiency and less cross-regulation at the same time. To verify the feasibility of the proposed controller, an SIDO buck converter with two regulated output voltages, 1.8 V and 3.3 V, is designed and fabricated in HEJIAN 0.35 μm CMOS process. Simulation and experiment results show that the transient time of this SIDO buck converter drops to 10 μs while the cross-regulation is reduced to 0.057 mV/mA, when its first load changes from 50 to 100 mA.

Series-Connected Buck Boost Regulators

NASA Technical Reports Server (NTRS)

Birchenough, Arthur G.

2005-01-01

A series-connected buck boost regulator (SCBBR) is an electronic circuit that bucks a power-supply voltage to a lower regulated value or boosts it to a higher regulated value. The concept of the SCBBR is a generalization of the concept of the SCBR, which was reported in "Series-Connected Boost Regulators" (LEW-15918), NASA Tech Briefs, Vol. 23, No. 7 (July 1997), page 42. Relative to prior DC-voltage-regulator concepts, the SCBBR concept can yield significant reductions in weight and increases in power-conversion efficiency in many applications in which input/output voltage ratios are relatively small and isolation is not required, as solar-array regulation or battery charging with DC-bus regulation. Usually, a DC voltage regulator is designed to include a DC-to-DC converter to reduce its power loss, size, and weight. Advances in components, increases in operating frequencies, and improved circuit topologies have led to continual increases in efficiency and/or decreases in the sizes and weights of DC voltage regulators. The primary source of inefficiency in the DC-to-DC converter portion of a voltage regulator is the conduction loss and, especially at high frequencies, the switching loss. Although improved components and topology can reduce the switching loss, the reduction is limited by the fact that the converter generally switches all the power being regulated. Like the SCBR concept, the SCBBR concept involves a circuit configuration in which only a fraction of the power is switched, so that the switching loss is reduced by an amount that is largely independent of the specific components and circuit topology used. In an SCBBR, the amount of power switched by the DC-to-DC converter is only the amount needed to make up the difference between the input and output bus voltage. The remaining majority of the power passes through the converter without being switched. The weight and power loss of a DC-to-DC converter are determined primarily by the amount of power processed. In the SCBBR, the unswitched majority of the power is passed through with very little power loss, and little if any increase in the sizes of the converter components is needed to enable the components to handle the unswitched power. As a result, the power-conversion efficiency of the regulator can be very high, as shown in the example of Figure 1. A basic SCBBR includes a DC-to-DC converter (see Figure 2). The switches and primary winding of a transformer in the converter is connected across the input bus, while the secondary winding and switches are connected in series with the output bus, so that the output voltage is the sum of the input voltage and the secondary voltage of the converter. In the breadboard SCBBR, the input voltage applied to the primary winding is switched by use of metal oxide/semiconductor field-effect transistors (MOSFETs) in a full bridge circuit; the secondary winding is center-tapped, with two MOSFET switches and diode rectifiers connected in opposed series in each leg. The sets of opposed switches and rectifiers are what enable operation in either a boost or a buck mode. In the boost mode, input voltage and current, and the output voltage and current are all positive; that is, the secondary voltage is added to the input voltage and the net output voltage can be regulated at a value equal or greater than the input voltage. In the buck mode, input voltage is still positive and the current still flows in the same direction in the secondary, but the switches are controlled such that some power flows from the secondary to the primary. The voltage across the secondary and the current into the primary are reversed. The result is that the output voltage is lower than the input voltage, and some power is recirculated from the converter secondary back to the input. Quantitatively, the advantage of an SCBBR is a direct function of the regulation range required. If, for example, a regulation range of 20 percent is required for a 500-W supply, th it suffices to design the DC-to-DC converter in the SCBBR for a power rating of only 100 W. The switching loss and size are much smaller than those of a conventional regulator that must be rated for switching of all 500 W. The reduction in size and the increase in efficiency are not directly proportional to switched-power ratio of 5:1 because the additional switches contribute some conduction loss and the input and output filters must be larger than those typically required for a 100-W converter. Nevertheless, the power loss and the size can be much smaller than those of a 500-W converter.

Space platform power system hardware testbed

NASA Technical Reports Server (NTRS)

Sable, D.; Patil, A.; Sizemore, T.; Deuty, S.; Noon, J.; Cho, B. H.; Lee, F. C.

1991-01-01

The scope of the work on the NASA Space Platform includes the design of a multi-module, multi-phase boost regulator, and a voltage-fed, push-pull autotransformer converter for the battery discharger. A buck converter was designed for the charge regulator. Also included is the associated mode control electronics for the charger and discharger, as well as continued development of a comprehensive modeling and simulation tool for the system. The design of the multi-module boost converter is discussed for use as a battery discharger. An alternative battery discharger design is discussed using a voltage-fed, push-pull autotransformer converter. The design of the charge regulator is explained using a simple buck converter. The design of the mode controller and effects of locating the bus filter capacitor bank 20 feet away from the power ORU are discussed. A brief discussion of some alternative topologies for battery charging and discharging is included. The power system modeling is described.

Input-current shaped ac to dc converters

NASA Technical Reports Server (NTRS)

1986-01-01

The problem of achieving near unity power factor while supplying power to a dc load from a single phase ac source of power is examined. Power processors for this application must perform three functions: input current shaping, energy storage, and output voltage regulation. The methods available for performing each of these three functions are reviewed. Input current shaping methods are either active or passive, with the active methods divided into buck-like and boost-like techniques. In addition to large reactances, energy storage methods include resonant filters, active filters, and active storage schemes. Fast voltage regulation can be achieved by post regulation or by supplementing the current shaping topology with an extra switch. Some indications of which methods are best suited for particular applications concludes the discussion.

An Balancing Strategy Based on SOC for Lithium-Ion Battery Pack

NASA Astrophysics Data System (ADS)

Li, Peng

2017-09-01

According to the two kinds of working state of a battery pack, we designed a balancing strategy based on SOC, and expounds the working principle of balanced control strategy: the battery is charging, the battery charged state of the highest monomer battery is balanced discharge, strong single battery charging current decreases, while the other single cell in the same group is not affected; the battery is in a discharge or static state, single cell battery is the weakest balanced charge, while the other single cell in the same group are not affected. In this paper, we design a kind of lithium ion battery charging and discharging equalizer based on Buck chopper circuit and Boost-Buck chopper circuit. The equalizer is balanced charging and discharging experiments of series four lithium iron phosphate battery, the experimental results show that this equalizer has not only improved the degree not equilibrium between single cells, and improve the battery charge and discharge capacity.

Silicon Carbide Diodes Characterization at High Temperature and Comparison With Silicon Devices

NASA Technical Reports Server (NTRS)

Lebron-Velilla, Ramon C.; Schwarze, Gene E.; Gardner, Brent G.; Adams, Jerry D., Jr.

2004-01-01

Commercially available silicon carbide (SiC) Schottky diodes from different manufacturers rated at 200, 300, 600, and 1200 V, were electrically tested and characterized as a function of temperature up to 300 C. Electrical tests included both steady state and dynamic tests. Steady state tests produced forward and reverse I-V characteristic curves. Transient tests evaluated the switching performance of the diodes in either a hard-switched DC to DC buck converter or a half-bridge boost converter. For evaluation and comparison purposes, the same tests were performed with current state-of-the-art ultra fast silicon (Si) pn-junction diodes of similar ratings and also a Si Schottky diode. The comparisons made were forward voltage drop at rated current, reverse current at rated voltage, and turn-off peak reverse recovery current and reverse recovery time. In addition, efficiency measurements were taken for the buck DC to DC converter using both the SiC Schottky diodes and the Si pn-junction diodes at different temperatures and frequencies. The test results showed that at high temperature, the forward voltage drop for SiC Schottky diodes is higher than the forward drop of the ultra fast Si pn-junction diodes. As the temperature increased, the forward voltage drop of the SiC Schottky increased while for the ultra fast Si pn-junction diodes, the forward voltage drop decreased as temperature increased. For the elevated temperature steady state reverse voltage tests, the SiC Schottky diodes showed low leakage current at their rated voltage. Likewise, for the transient tests, the SiC Schottky diodes displayed low reverse recovery currents over the range of temperatures tested. Conversely, the Si pn-junction diodes showed increasing peak reverse current values and reverse recovery times with increasing temperature. Efficiency measurements in the DC to DC buck converter showed the advantage of the SiC Schottky diodes over the ultra fast Si pn-junction diodes, especially at the higher temperatures and higher frequencies.

Sexual maturation and fertility of male Nigerian Dwarf goat (Capra hircus) clones produced by somatic cell nuclear transfer.

PubMed

Gauthier, M; Pierson, J; Drolet, M; Bhatia, B; Baldassarre, H; Keefer, C L

2001-01-01

Three, genetically identical, Nigerian Dwarf bucks produced by somatic cell nuclear transfer (NT) of fetal fibroblasts were monitored for sexual maturation and fertility. Starting at four months of age, these male clones were trained to serve an artificial vagina (AV). Average age of the NT-derived bucks at first semen collection was 20 weeks, which was not different from that of other young bucks of this breed (average age at first collection = 20 weeks). Average sperm production at 5 months of age for the NT-derived bucks was 5.0 x 10(8) spermatozoa, which was comparable to that of dwarf bucks of similar age (3.4 x 10(8) spermatozoa). At seven months of age, semen collected from two NT-derived bucks was used to artificially inseminate six females (three does per buck). Five does were confirmed pregnant by ultrasound at day 42. Nine healthy kids, four males and five females, were born in March and April 2000. Viable spermatozoa were collected from one of the F1 males at 28 weeks of age. These results demonstrated that NT-derived bucks and one of their male offspring developed sexually within the normal timeframe for their breed and that the clones were fertile.

Radiation Effects on DC-DC Converters

NASA Technical Reports Server (NTRS)

Zhang, De-Xin; AbdulMazid, M. D.; Attia, John O.; Kankam, Mark D. (Technical Monitor)

2001-01-01

In this work, several DC-DC converters were designed and built. The converters are Buck Buck-Boost, Cuk, Flyback, and full-bridge zero-voltage switched. The total ionizing dose radiation and single event effects on the converters were investigated. The experimental results for the TID effects tests show that the voltages of the Buck Buck-Boost, Cuk, and Flyback converters increase as total dose increased when using power MOSFET IRF250 as a switching transistor. The change in output voltage with total dose is highest for the Buck converter and the lowest for Flyback converter. The trend of increase in output voltages with total dose in the present work agrees with those of the literature. The trends of the experimental results also agree with those obtained from PSPICE simulation. For the full-bridge zero-voltage switch converter, it was observed that the dc-dc converter with IRF250 power MOSFET did not show a significant change of output voltage with total dose. In addition, for the dc-dc converter with FSF254R4 radiation-hardened power MOSFET, the output voltage did not change significantly with total dose. The experimental results were confirmed by PSPICE simulation that showed that FB-ZVS converter with IRF250 power MOSFET's was not affected with the increase in total ionizing dose. Single Event Effects (SEE) radiation tests were performed on FB-ZVS converters. It was observed that the FB-ZVS converter with the IRF250 power MOSFET, when the device was irradiated with Krypton ion with ion-energy of 150 MeV and LET of 41.3 MeV-square cm/mg, the output voltage increased with the increase in fluence. However, for Krypton with ion-energy of 600 MeV and LET of 33.65 MeV-square cm/mg, and two out of four transistors of the converter were permanently damaged. The dc-dc converter with FSF254R4 radiation hardened power MOSFET's did not show significant change at the output voltage with fluence while being irradiated by Krypton with ion energy of 1.20 GeV and LET of 25.97 MeV-square cm/mg. This might be due to fact that the device is radiation hardened.

Fuel cells, batteries and super-capacitors stand-alone power systems management using optimal/flatness based-control

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

Benaouadj, M.; Aboubou, A.; Bahri, M.

2016-07-25

In this work, an optimal control (under constraints) based on the Pontryagin’s maximum principle is used to optimally manage energy flows in a basic PEM (Proton Exchange Membrane) fuel cells system associated to lithium-ion batteries and supercapacitors through a common DC bus having a voltage to stabilize using the differential flatness approach. The adaptation of voltage levels between different sources and load is ensured by use of three DC-DC converters, one boost connected to the PEM fuel cells, while the two others are buck/boost and connected to the lithiumion batteries and supercapacitors. The aim of this paper is to developmore » an energy management strategy that is able to satisfy the following objectives: Impose the power requested by a habitat (representing the load) according to a proposed daily consumption profile, Keep fuel cells working at optimal power delivery conditions, Maintain constant voltage across the common DC bus, Stabilize the batteries voltage and stored quantity of charge at desired values given by the optimal control. Results obtained under MATLAB/Simulink environment prove that the cited objectives are satisfied, validating then, effectiveness and complementarity between the optimal and flatness concepts proposed for energy management. Note that this study is currently in experimentally validation within MSE Laboratory.« less

Fuzzy control of power converters based on quasilinear modelling

NASA Astrophysics Data System (ADS)

Li, C. K.; Lee, W. L.; Chou, Y. W.

1995-03-01

Unlike feedback control by the fuzzy PID method, a new fuzzy control algorithm based on quasilinear modelling of the DC-DC converter is proposed. Investigation is carried out using a buck-boost converter. Simulation results demonstrated that the converter can be regulated with improved performance even when subjected to input disturbance and load variation.

Design of a hybrid battery charger system fed by a wind-turbine and photovoltaic power generators.

PubMed

Chang Chien, Jia-Ren; Tseng, Kuo-Ching; Yan, Bo-Yi

2011-03-01

This paper is aimed to develop a digital signal processor (DSP) for controlling a solar cell and wind-turbine hybrid charging system. The DSP consists of solar cells, a wind turbine, a lead acid battery, and a buck-boost converter. The solar cells and wind turbine serve as the system's main power sources and the battery as an energy storage element. The output powers of solar cells and wind turbine have large fluctuations with the weather and climate conditions. These unstable powers can be adjusted by a buck-boost converter and thus the most suitable output powers can be obtained. This study designs a booster by using a dsPIC30F4011 digital signal controller as a core processor. The DSP is controlled by the perturbation and observation methods to obtain an effective energy circuit with a full 100 W charging system. Also, this DSP can, day and night, be easily controlled and charged by a simple program, which can change the state of the system to reach a flexible application based on the reading weather conditions.

Male goat vocalizations stimulate the estrous behavior and LH secretion in anestrous goats that have been previously exposed to bucks.

PubMed

Delgadillo, José Alberto; Vielma, Jesús; Hernandez, Horacio; Flores, José Alfredo; Duarte, Gerardo; Fernández, Ilda Graciela; Keller, Matthieu; Gelez, Hélène

2012-09-01

We investigated whether live vocalizations emitted by bucks interacting with anestrous females stimulate secretion of LH, estrous behavior and ovulation in anestrous goats. In experiment 1, bucks rendered sexually active by exposure to long days followed by natural photoperiod were exposed in a light-proof-building to five anestrous females. Buck vocalizations were reproduced through a microphone-amplifier-loudspeaker system to an open pen where one group of goats (n=6) was exposed for 10 days to these live vocalizations. Another group of females (n=6) was isolated from males and vocalizations. The proportion of goats displaying estrous behavior was significantly higher in females exposed to buck vocalizations than in females isolated from males. The proportion of goats that ovulated did not differ between the 2 groups (exposed to males versus isolated). In experiment 2, female goats that either had previous contact with males (n=7), or no previous contact with males (n=7) were exposed to live buck vocalizations, reproduced as described in experiment 1, for 5 days. The number and amplitude of LH pulses did not differ between groups before exposition to buck vocalizations. Five days of exposure to male vocalizations significantly increased LH pulsatility only in females that had previous contact with males, while LH pulse amplitude was not modified. We concluded that live buck vocalizations can stimulate estrous behavior and LH secretion in goats if they have had previous contact with bucks. Copyright © 2012 Elsevier Inc. All rights reserved.

Differential distribution of Y-chromosome haplotypes in Swiss and Southern European goat breeds.

PubMed

Vidal, Oriol; Drögemüller, Cord; Obexer-Ruff, Gabriela; Reber, Irene; Jordana, Jordi; Martínez, Amparo; Bâlteanu, Valentin Adrian; Delgado, Juan Vicente; Eghbalsaied, Shahin; Landi, Vincenzo; Goyache, Felix; Traoré, Amadou; Pazzola, Michele; Vacca, Giuseppe Massimo; Badaoui, Bouabid; Pilla, Fabio; D'Andrea, Mariasilvia; Álvarez, Isabel; Capote, Juan; Sharaf, Abdoallah; Pons, Àgueda; Amills, Marcel

2017-11-23

The analysis of Y-chromosome variation has provided valuable clues about the paternal history of domestic animal populations. The main goal of the current work was to characterize Y-chromosome diversity in 31 goat populations from Central Eastern (Switzerland and Romania) and Southern Europe (Spain and Italy) as well as in reference populations from Africa and the Near East. Towards this end, we have genotyped seven single nucleotide polymorphisms (SNPs), mapping to the SRY, ZFY, AMELY and DDX3Y Y-linked loci, in 275 bucks from 31 populations. We have observed a low level of variability in the goat Y-chromosome, with just five haplotypes segregating in the whole set of populations. We have also found that Swiss bucks carry exclusively Y1 haplotypes (Y1A: 24%, Y1B1: 15%, Y1B2: 43% and Y1C: 18%), while in Italian and Spanish bucks Y2A is the most abundant haplotype (77%). Interestingly, in Carpathian goats from Romania the Y2A haplotype is also frequent (42%). The high Y-chromosome differentiation between Swiss and Italian/Spanish breeds might be due to the post-domestication spread of two different Near Eastern genetic stocks through the Danubian and Mediterranean corridors. Historical gene flow between Southern European and Northern African goats might have also contributed to generate such pattern of genetic differentiation.

Regulation of a lightweight high efficiency capacitator diode voltage multiplier dc-dc converter

NASA Technical Reports Server (NTRS)

Harrigill, W. T., Jr.; Myers, I. T.

1976-01-01

A method for the regulation of a capacitor diode voltage multiplier dc-dc converter has been developed which has only minor penalties in weight and efficiency. An auxiliary inductor is used, which only handles a fraction of the total power, to control the output voltage through a pulse width modulation method in a buck boost circuit.

Exploration of the Chaotic Behaviour in a Buck-Boost Converter Depending on the Converter and Load Elements

NASA Astrophysics Data System (ADS)

Demirbaş, Şevki; Fidanboy, Hikmet; Kurt, Erol

2016-08-01

In this paper, detailed analyses of the chaotic behavior observed in a buck-boost converter are presented. Although this basic converter system is already known world-wide for the purpose of dc-dc conversion of the output of renewable energy systems, it indicates certain chaotic regimes where both the output amplitude and frequency change randomly. This chaotic regime can yield an unstable output over the resistive or resistive/inductive electrical loads. This study presents a detailed map for the regular and chaotic regions in terms of material parameters, such as converter capacitance C, resistive load R, and inductive load L. Thus, the stable area of operation for efficient and renewable electricity production will be ascertained for the studied converter system. We emphasize that the material parameters C, R, and L play important roles in generating energy from the solar cell; indeed, the stability increases with higher values of the converter capacitor and load inductance, whereas it decreases according to the resistive load. A number of periodic windows have been observed and the output frequency gives a broad-band spectrum of up to 50 kHz.

High performance ripple feedback for the buck unity-power-factor rectifier

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

Lo, Y.W.; King, R.J.

1995-03-01

The buck unity-power-factor rectifier has harmonic-free input current with complete load regulation down to zero output voltage. A new ``nonlinear ripple feedback`` is proposed which exactly cancels the spoiling effect of dc-side current ripple on the low-distortion ac line current waveforms, even for large amounts of ripple. This cancellation is independent of operating point and readily implemented with analog hardware, thereby permitting economies in the design of the dc filter while maintaining harmonic-free operation. Both large-signal and incremental analyses of the rectifier are given. Confirming experimental results from a 1-kW 48-V isolated battery charger operating with current-ripple levels ranging frommore » 50% to discontinuous-conduction-mode operation are given.« less

Tracking the global maximum power point of PV arrays under partial shading conditions

NASA Astrophysics Data System (ADS)

Fennich, Meryem

This thesis presents the theoretical and simulation studies of the global maximum power point tracking (MPPT) for photovoltaic systems under partial shading. The main goal is to track the maximum power point of the photovoltaic module so that the maximum possible power can be extracted from the photovoltaic panels. When several panels are connected in series with some of them shaded partially either due to clouds or shadows from neighboring buildings, several local maxima appear in the power vs. voltage curve. A power increment based MPPT algorithm is effective in identifying the global maximum from the several local maxima. Several existing MPPT algorithms are explored and the state-of-the-art power increment method is simulated and tested for various partial shading conditions. The current-voltage and power-voltage characteristics of the PV model are studied under different partial shading conditions, along with five different cases demonstrating how the MPPT algorithm performs when shading switches from one state to another. Each case is supplemented with simulation results. The method of tracking the Global MPP is based on controlling the DC-DC converter connected to the output of the PV array. A complete system simulation including the PV array, the direct current to direct current (DC-DC) converter and the MPPT is presented and tested using MATLAB software. The simulation results show that the MPPT algorithm works very well with the buck converter, while the boost converter needs further changes and implementation.

High-frequency high-voltage high-power DC-to-DC converters

NASA Astrophysics Data System (ADS)

Wilson, T. G.; Owen, H. A., Jr.; Wilson, P. M.

1981-07-01

The current and voltage waveshapes associated with the power transitor and the power diode in an example current-or-voltage step-up (buck-boost) converter were analyzed to highlight the problems and possible tradeoffs involved in the design of high voltage high power converters operating at switching frequencies in the range of 100 Khz. Although the fast switching speeds of currently available power diodes and transistors permit converter operation at high switching frequencies, the resulting time rates of changes of current coupled with parasitic inductances in series with the semiconductor switches, produce large repetitive voltage transients across the semiconductor switches, potentially far in excess of the device voltage ratings. The need is established for semiconductor switch protection circuitry to control the peak voltages appearing across the semiconductor switches, as well as to provide the waveshaping action require for a given semiconductor device. The possible tradeoffs, as well as the factors affecting the tradeoffs that must be considered in order to maximize the efficiency of the converters are enumerated.

High-frequency high-voltage high-power DC-to-DC converters

NASA Technical Reports Server (NTRS)

Wilson, T. G.; Owen, H. A., Jr.; Wilson, P. M.

1981-01-01

The current and voltage waveshapes associated with the power transitor and the power diode in an example current-or-voltage step-up (buck-boost) converter were analyzed to highlight the problems and possible tradeoffs involved in the design of high voltage high power converters operating at switching frequencies in the range of 100 Khz. Although the fast switching speeds of currently available power diodes and transistors permit converter operation at high switching frequencies, the resulting time rates of changes of current coupled with parasitic inductances in series with the semiconductor switches, produce large repetitive voltage transients across the semiconductor switches, potentially far in excess of the device voltage ratings. The need is established for semiconductor switch protection circuitry to control the peak voltages appearing across the semiconductor switches, as well as to provide the waveshaping action require for a given semiconductor device. The possible tradeoffs, as well as the factors affecting the tradeoffs that must be considered in order to maximize the efficiency of the converters are enumerated.

A High-Efficiency Wind Energy Harvester for Autonomous Embedded Systems

PubMed Central

Brunelli, Davide

2016-01-01

Energy harvesting is currently a hot research topic, mainly as a consequence of the increasing attractiveness of computing and sensing solutions based on small, low-power distributed embedded systems. Harvesting may enable systems to operate in a deploy-and-forget mode, particularly when power grid is absent and the use of rechargeable batteries is unattractive due to their limited lifetime and maintenance requirements. This paper focuses on wind flow as an energy source feasible to meet the energy needs of a small autonomous embedded system. In particular the contribution is on the electrical converter and system integration. We characterize the micro-wind turbine, we define a detailed model of its behaviour, and then we focused on a highly efficient circuit to convert wind energy into electrical energy. The optimized design features an overall volume smaller than 64 cm3. The core of the harvester is a high efficiency buck-boost converter which performs an optimal power point tracking. Experimental results show that the wind generator boosts efficiency over a wide range of operating conditions. PMID:26959018

A High-Efficiency Wind Energy Harvester for Autonomous Embedded Systems.

PubMed

Brunelli, Davide

2016-03-04

Energy harvesting is currently a hot research topic, mainly as a consequence of the increasing attractiveness of computing and sensing solutions based on small, low-power distributed embedded systems. Harvesting may enable systems to operate in a deploy-and-forget mode, particularly when power grid is absent and the use of rechargeable batteries is unattractive due to their limited lifetime and maintenance requirements. This paper focuses on wind flow as an energy source feasible to meet the energy needs of a small autonomous embedded system. In particular the contribution is on the electrical converter and system integration. We characterize the micro-wind turbine, we define a detailed model of its behaviour, and then we focused on a highly efficient circuit to convert wind energy into electrical energy. The optimized design features an overall volume smaller than 64 cm³. The core of the harvester is a high efficiency buck-boost converter which performs an optimal power point tracking. Experimental results show that the wind generator boosts efficiency over a wide range of operating conditions.

A High Power Density Single-Phase PWM Rectifier With Active Ripple Energy Storage

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

Wang, Ruxi; Wang, Fei; Boroyevich, Dushan

It is well known that single-phase pulse width modulation rectifiers have second-order harmonic currents and corresponding ripple voltages on the dc bus. The low-frequency harmonic current is normally filtered using a bulk capacitor in the bus, which results in low power density. However, pursuing high power density in converter design is a very important goal in the aerospace applications. This paper studies methods for reducing the energy storage capacitor for single-phase rectifiers. The minimum ripple energy storage requirement is derived independently of a specific topology. Based on theminimum ripple energy requirement, the feasibility of the active capacitor s reduction schemesmore » is verified. Then, we propose a bidirectional buck boost converter as the ripple energy storage circuit, which can effectively reduce the energy storage capacitance. The analysis and design are validated by simulation and experimental results.« less

Solar power generation system for reducing leakage current

NASA Astrophysics Data System (ADS)

Wu, Jinn-Chang; Jou, Hurng-Liahng; Hung, Chih-Yi

2018-04-01

This paper proposes a transformer-less multi-level solar power generation system. This solar power generation system is composed of a solar cell array, a boost power converter, an isolation switch set and a full-bridge inverter. A unipolar pulse-width modulation (PWM) strategy is used in the full-bridge inverter to attenuate the output ripple current. Circuit isolation is accomplished by integrating the isolation switch set between the solar cell array and the utility, to suppress the leakage current. The isolation switch set also determines the DC bus voltage for the full-bridge inverter connecting to the solar cell array or the output of the boost power converter. Accordingly, the proposed transformer-less multi-level solar power generation system generates a five-level voltage, and the partial power of the solar cell array is also converted to AC power using only the full-bridge inverter, so the power efficiency is increased. A prototype is developed to validate the performance of the proposed transformer-less multi-level solar power generation system.

Analysis of Extended Z-source Inverter for Photovoltaic System

NASA Astrophysics Data System (ADS)

Prakash, G.; Subramani, C.; Dhineshkumar, K.; Rayavel, P.

2018-04-01

The Z-source inverter has picked up prominence as a solitary stage buck-support inverter topology among numerous specialists. Notwithstanding, its boosting capacity could be constrained, and in this manner, it may not be reasonable for a few applications requiring high lift request of falling other dc-dc help converters. The Z-source inverter is a recent converter topology that exhibits both voltage-buck and voltage-boost capability This could lose the effectiveness and request all the more detecting for controlling the additional new stages. This paper is proposing another group of broadened help semi Z - source inverter (ZSI) to fill the exploration hole left in the improvement of ZSI. These new topologies can be worked with same regulation strategies that were produced for unique ZSI. Likewise, they have a similar number of dynamic switches as unique ZSI saving the single-organize nature of ZSI. Proposed topologies are dissected in the enduring state and their exhibitions are approved utilizing recreated comes about acquired in MATLAB/Simulink. Besides, they are tentatively approved with comes about acquired from a model created in the research facility. The trend of fast increase of the PV energy use is related to the increasing efficiency of solar cells as well as the improvements of manufacturing technology of solar panels.

Practical Design Guidelines of qZSI Based Step-Up DC/DC Converter

NASA Astrophysics Data System (ADS)

Zakis, Janis; Vinnikov, Dmitri; Roasto, Indrek; Jalakas, Tanel

2010-01-01

This paper presents some design guidelines for a new voltage fed step-up DC/DC isolated converter. The most significant advantage of proposed converter is voltage buck-boost operation on single stage. The most promising application for proposed converter is in the field of distributed power generation e.g. fuel cells or photovoltaic. The most sensitive issues - such as power losses caused by high currents in the input side of converter and high transient overvoltages across the inverter bridge caused by stray inductances were discussed and solved. The proposals and recommendations to overcome these issues are given in the paper. The Selection and design guidelines of converter elements are proposed and explained. The prototype of proposed converter was built and experimentally tested. Some results are presented and evaluated.

Series Connected Converter for Control of Multi-Bus Spacecraft Power Utility

NASA Technical Reports Server (NTRS)

Beach, Raymond F. (Inventor); Brush, Andy (Inventor)

1997-01-01

The invention provides a power system using series connected regulators. Power from a source, such as a solar array, is processed through the regulators and provided to corresponding buses used to charge a battery and supply loads. The regulators employ a bypass loop around a DC-DC converter. The bypass loop connects a hot input of the converter to a return output, preferably though an inductor. Part of the current from the source passes through the bypass loop to the power bus. The converter bucks or boosts the voltage from the source to maintain the desired voltage at the bus. Thus, only part of the power is processed through the converter. The converter can also be used without the bypass loop to provide isolation. All of the converters can be substantially identical.

Performance analyses of Z-source and quasi Z-source inverter for photovoltaic applications

NASA Astrophysics Data System (ADS)

Himabind, S.; Priya, T. Hari; Manjeera, Ch.

2018-04-01

This paper presents the comparative analysis of Z-source and Quasi Z-source converter for renewable energy applications. Due to the dependency of renewable energy sources on external weather conditions the output voltage, current changes accordingly which effects the performance of traditional voltage source and current source inverters connected across it. To overcome the drawbacks of VSI and CSI, Z-source and Quasi Z-source inverter (QZSI) are used, which can perform multiple tasks like ac-to-dc, dc-to-ac, ac-to-ac, dc-to-dc conversion. They can be used for both buck and boost operations, by utilizing the shoot-through zero state. The QZSI is derived from the ZSI topology, with a slight change in the impedance network and it overcomes the drawbacks of ZSI. The QZSI draws a constant current from the source when compared to ZSI. A comparative analysis is performed between Z-source and Quasi Z-source inverter, simulation is performed in MATLAB/Simulink environment.

Integrated mixed signal control IC for 500-kHz switching frequency buck regulator

NASA Astrophysics Data System (ADS)

Chen, Keng; Zhang, Hong

2015-12-01

The main purpose for this work is to study the challenges of designing a digital buck regulator using pipelined analog to digital converter (ADC). Although pipelined ADC can achieve high sampling speed, it will introduce additional phase lag to the buck circuit. Along with the latency brought by processing time of additional digital circuits, as well as the time delay associated with the switching frequency, the closed loop will be unstable; moreover, raw ADC outputs have low signal-to-noise ratio, which usually need back-end calibration. In order to compensate these phase lag and make control loop unconditional stable, as well as boost up signal-to-noise ratio of the ADC block with cost-efficient design, a finite impulse response filter followed by digital proportional-integral-derivative blocks were designed. All these digital function blocks were optimised with processing speed. In the system simulation, it can be found that this controller achieved output regulation within 10% of nominal 5 V output voltage under 1 A/µs load transient condition; moreover, with the soft-start method, there is no turn-on overshooting. The die size of this controller is controlled within 3 mm2 by using 180 nm CMOS technology.

A zero-voltage-switched three-phase interleaved buck converter

NASA Astrophysics Data System (ADS)

Hsieh, Yao-Ching; Huang, Bing-Siang; Lin, Jing-Yuan; Pham, Phu Hieu; Chen, Po-Hao; Chiu, Huang-Jen

2018-04-01

This paper proposes a three-phase interleaved buck converter which is composed of three identical paralleled buck converters. The proposed solution has three shunt inductors connected between each other of three basic buck conversion units. With the help of the shunt inductors, the MOSFET parasitic capacitances will resonate to achieve zero-voltage-switching. Furthermore, the decreasing rate of the current through the free-wheeling diodes is limited, and therefore, their reverse-recovery losses can be minimised. The active power switches are controlled by interleaved pulse-width modulation signals to reduce the input and output current ripples. Therefore, the filtering capacitances on the input and output sides can be reduced. The power efficiency is measured to be as high as 98% in experiment with a prototype circuit.

19. Photocopy of photograph (source uncertain; probably Bucks County Historical ...

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

19. Photocopy of photograph (source uncertain; probably Bucks County Historical Society) ca. 1916, photographer unknown SHOWING CONSTRUCTION ESSENTIALLY COMPLETED. MERCER'S CAPTION READS: 'ON SATURDAY EVENING, NOVEMBER 13th AT 5: 15 P.M. THE WORKMEN HAVING AT FIVE O'CLOCK FINISHED THE CONSTRUCTION OF THE NEW BUILDING OF THE MUSEUM OF THE BUCKS COUNTY HISTORICAL SOCIETY AT DOYLESTOWN, A BAND OF TRAVELLING MUSICIANS STOPPED UNASKED AT NO. 196 GREEN STREET OPPOSITE THE SOUTHEAST GABLE OF THE BUILDING AND I HEARD THEM PLAY THE GERMAN SONG SHOWN BELOW, TRANSLATED 'WE HAD BUILT A STATELY HOUSE, AND DEDICATED IT TO GOD, AGAINST RAIN, STORM AND DISASTER' I CALLED THEM BACK TO PLAY IT AGAIN, BUT THEY MISUNDERSTOOD ME AND WENT AWAY. HENRY C. MERCER' - Mercer Museum, Pine & Ashland Streets, Doylestown, Bucks County, PA

Single Active Switch PV Inverter

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

Ramanan, V. R.; Pan, Zhiguo

This report presents a new PV inverter topology that uses only one active switch instead of 7 active switches in a conventional PV inverter. It has a buck boost converter and operates at discontinuous current control mode, which can reduce the output stage from an active switch bridge to a thyristor bridge. This concept, if successfully demonstrated, may have great cost and size/weight benefits over conventional solutions. Since the proposed topology is completely different from the traditional boost converter plus voltage source inverter approach, there is no existing control/modulation scheme available. A new modulation scheme for both the main switchmore » and the thyristors has been developed. An active clamping circuit has also been proposed to reduce switching losses and voltage spike during the switching transient. A simulation model has been set up to validate the control algorithm and clamping circuit. Simulated results show that a proposed 10 kW PV inverter can reach 5% total harmonic distortion (THD), 98.8% peak efficiency with only one main active switch, and an inductor weighing less than 3 kg. Based on that, a 10 kW prototype converter has been designed and built.« less

PSO Based PI Controller Design for a Solar Charger System

PubMed Central

Yau, Her-Terng; Lin, Chih-Jer; Liang, Qin-Cheng

2013-01-01

Due to global energy crisis and severe environmental pollution, the photovoltaic (PV) system has become one of the most important renewable energy sources. Many previous studies on solar charger integrated system only focus on load charge control or switching Maximum Power Point Tracking (MPPT) and charge control modes. This study used two-stage system, which allows the overall portable solar energy charging system to implement MPPT and optimal charge control of Li-ion battery simultaneously. First, this study designs a DC/DC boost converter of solar power generation, which uses variable step size incremental conductance method (VSINC) to enable the solar cell to track the maximum power point at any time. The voltage was exported from the DC/DC boost converter to the DC/DC buck converter, so that the voltage dropped to proper voltage for charging the battery. The charging system uses constant current/constant voltage (CC/CV) method to charge the lithium battery. In order to obtain the optimum PI charge controller parameters, this study used intelligent algorithm to determine the optimum parameters. According to the simulation and experimental results, the control parameters resulted from PSO have better performance than genetic algorithms (GAs). PMID:23766713

PSO based PI controller design for a solar charger system.

PubMed

Yau, Her-Terng; Lin, Chih-Jer; Liang, Qin-Cheng

2013-01-01

Due to global energy crisis and severe environmental pollution, the photovoltaic (PV) system has become one of the most important renewable energy sources. Many previous studies on solar charger integrated system only focus on load charge control or switching Maximum Power Point Tracking (MPPT) and charge control modes. This study used two-stage system, which allows the overall portable solar energy charging system to implement MPPT and optimal charge control of Li-ion battery simultaneously. First, this study designs a DC/DC boost converter of solar power generation, which uses variable step size incremental conductance method (VSINC) to enable the solar cell to track the maximum power point at any time. The voltage was exported from the DC/DC boost converter to the DC/DC buck converter, so that the voltage dropped to proper voltage for charging the battery. The charging system uses constant current/constant voltage (CC/CV) method to charge the lithium battery. In order to obtain the optimum PI charge controller parameters, this study used intelligent algorithm to determine the optimum parameters. According to the simulation and experimental results, the control parameters resulted from PSO have better performance than genetic algorithms (GAs).

Comparison of control structures for a bidirectional high-frequency dc-dc converter

NASA Astrophysics Data System (ADS)

Himmelstoss, Felix A.; Kolar, Johann W.; Zach, Franz C.

1989-08-01

A system for dc-dc power conversion based on a buck-boost converter topology is presented. It makes power flow in both directions possible. The possibility of bidirectional power flow is useful for certain applications, such as uninterruptable power supplies. Starting from a structural diagram the transfer function of the system is derived. The controller for the converter is then designed. It is made up of a simple voltage controller, a voltage controller with an inner loop current controller (cascade control) and with two kinds of state space control. The transfer functions of the different system parts are derived and dimensioning guidelines for the controller sections are presented. The closed loop behavior of the bidirectional converter for the different control structures is analyzed based on simulation using duty cycle averaging. Bodediagrams and step responses are shown.

A three-dimensional bucking system for optimal bucking of Central Appalachian hardwoods

Treesearch

Jingxin Wang; Jingang Liu; Chris B. LeDoux

2009-01-01

An optimal tree stembucking systemwas developed for central Appalachian hardwood species using three-dimensional (3D) modeling techniques. ActiveX Data Objects were implemented via MS Visual C++/OpenGL to manipulate tree data which were supported by a backend relational data model with five data entity types for stems, grades and prices, logs, defects, and stem shapes...

Comparison of Two Railgun Power Supply Architectures to Quantify the Energy Dissipated After the Projectile Leaves the Railgun

DTIC Science & Technology

2016-06-01

inch gun on impact [1]. The potential of the EM railgun renders the need to store dangerous explosives associated with the conventional warheads...leaves the gun . The simulation will outline some critical performance characteristics of a buck-boost power supply as compared to a thyristor-based...between the rails and from the projectile position along the length of the gun x [5]: 3 1 2 𔃻 2 2 w o

Ethylene dibromide (EDB) trends in the upper Floridan Aquifer, Seminole County, Georgia, October 1981 to November 1987

USGS Publications Warehouse

McConnell, J.B.

1988-01-01

Results of an investigation to assess the persistence and trends of ethylene dibromide (EDB) in the Upper Floridan aquifer, in Georgia indicate that in November 1987, EDB was present in the groundwater 4 years after it was last applied as a soil fumigant in the intensively farmed area of central Seminole County. At that time, EDB was detected in water samples from one domestic well and four irrigation wells. Concentrations ranged from less than 0.01 micrograms/L to 3.3 micrograms/L. The investigation in November 1987 revealed the groundwater contamination was limited to the 4-sq-mi area in the vicinity of Buck Hole, a sinkhole in a swampy depression in the central part of the County. In three of the five wells in which EDB was detected, concentrations have not changed significantly since August 1983. However, in one irrigation well near Buck Hole, the concentration decreased from 110 to 0.7 microgram/L since October 1981. In another irrigation well near Buck Hole, the concentration decreased from 26 to about 2.5 microgram/L during that period. The groundwater level data indicate that from Buck Hole, the hydraulic gradient in the Upper Floridan aquifer is about 2.8 ft/mi toward the east. However, the movement of EDB from the area of relatively high concentration near Buck Hole in the direction of inferred flow lines is not apparent. Although concentration gradients were not detected along flow lines, the movement of water induced by pumping wells W4 and W5 produced short-term decreasing and increasing trends in EDB Concentrations in wells W4 and W5, respectively. (USGS)

Analysis of transistor and snubber turn-off dynamics in high-frequency high-voltage high-power converters

NASA Technical Reports Server (NTRS)

Wilson, P. M.; Wilson, T. G.; Owen, H. A., Jr.

1982-01-01

Dc to dc converters which operate reliably and efficiently at switching frequencies high enough to effect substantial reductions in the size and weight of converter energy storage elements are studied. A two winding current or voltage stepup (buck boost) dc-to-dc converter power stage submodule designed to operate in the 2.5-kW range, with an input voltage range of 110 to 180 V dc, and an output voltage of 250 V dc is emphasized. In order to assess the limitations of present day component and circuit technologies, a design goal switching frequency of 10 kHz was maintained. The converter design requirements represent a unique combination of high frequency, high voltage, and high power operation. The turn off dynamics of the primary circuit power switching transistor and its associated turn off snubber circuitry are investigated.

Analysis of transistor and snubber turn-off dynamics in high-frequency high-voltage high-power converters

NASA Astrophysics Data System (ADS)

Wilson, P. M.; Wilson, T. G.; Owen, H. A., Jr.

Dc to dc converters which operate reliably and efficiently at switching frequencies high enough to effect substantial reductions in the size and weight of converter energy storage elements are studied. A two winding current or voltage stepup (buck boost) dc-to-dc converter power stage submodule designed to operate in the 2.5-kW range, with an input voltage range of 110 to 180 V dc, and an output voltage of 250 V dc is emphasized. In order to assess the limitations of present day component and circuit technologies, a design goal switching frequency of 10 kHz was maintained. The converter design requirements represent a unique combination of high frequency, high voltage, and high power operation. The turn off dynamics of the primary circuit power switching transistor and its associated turn off snubber circuitry are investigated.

First impressions and beyond: marketing your practice in touch points--Part II.

PubMed

Bisera, Cheryl

2012-01-01

When calling in a marketing expert to boost a practice's numbers, administrators and providers are usually looking for external marketing strategies--ways to attract new patients to the practice. However, one of the most important, yet often overlooked, elements to successfully marketing a practice is the very important work of retaining current patients and turning them into enthusiastic referrers. When new patients are simply filling the place of previous patients that have moved on, you are not building solid practice growth. You can create an atmosphere of loyal referring patients by providing positive touch points that fulfill the needs of your patients. This article will cover touch points that occur before a patient has chosen your practice. Laying the groundwork for positive touch points will give your marketing efforts a snowball effect, build growth, and deliver the most bang for your marketing bucks.

A hybrid power system for unmanned aerial vehicle electromagnetic launcher

NASA Astrophysics Data System (ADS)

Wang, Zhiren; Wu, Jun; Huang, Shengjun

2018-06-01

According to the UAV electromagnetic catapult with fixed timing, a hybrid energy storage system consist with battery and super capacitor is designed, in order to reduce the volume and weight of the energy storage system. The battery is regarded as the energy storage device and the super capacitor as power release device. Firstly, the battery charges the super capacitor, and then the super capacitor supplies power to electromagnetic catapult separately. The strategy is using the Buck circuit to charge the super capacitor with constant current and using the Boost circuit to make super capacitor provide a stable voltage circuit for electromagnetic catapult. The Simulink simulation results show that the designed hybrid energy storage system can meet the requirements of electromagnetic catapult. Compared with the system powered by the battery alone, the proposed scheme can reduce the number of batteries, and greatly reduce the volume and weight of the energy storage system.

Semen quality, antioxidant status and reproductive performance of rabbits bucks fed milk thistle seeds and rosemary leaves.

PubMed

Attia, Youssef A; Hamed, Rawia S; Bovera, Fulvia; Abd El-Hamid, Abd El-Hamid E; Al-Harthi, Mohammed A; Shahba, Hossam A

2017-09-01

The study aimed to investigate the effects of milk thistle seeds (MTS) and rosemary leaves (RL) both at 5 and 10g/kg diet on reproductive performance, semen quality and blood metabolites of rabbit bucks. A total of 35 rabbit bucks were randomly distributed into five experimental groups (7 bucks/group). All the groups were fed the same basal diet. The 1st group (control) did not have MTS and RL in its basal diet. The 2nd and 3rd groups were supplemented with MTS at 5 and 10g/kg, respectively. The 4th and 5th groups were fed the basal diet supplemented with RL at 5 and 10g/kg, respectively. The sperm concentration (SC), total sperm output (TSO), live sperm (LS), total live sperm (TLS) and total motile sperm (TMS) were significantly greater in the bucks fed MTS at 10 and RL at 5g/kg diet than the control group. Bucks fed MTS at 10g/kg diet had higher fertility than the control. Also, RL 5g/kg group showed higher testosterone and fertility than the control, but the MTS 10g/kg group showed the highest value for both parameters. In conclusion, MTS and RL at 10 and 5g/kg, respectively, significantly improved the semen quality and the fertility and MTS also increased the economic efficiency of rabbit bucks. Copyright © 2017 Elsevier B.V. All rights reserved.

Power Quality Improvement Using an Enhanced Network-Side-Shunt-Connected Dynamic Voltage Restorer

NASA Astrophysics Data System (ADS)

Fereidouni, Alireza; Masoum, Mohammad A. S.; Moghbel, Moayed

2015-10-01

Among the four basic dynamic voltage restorer (DVR) topologies, the network-side shunt-connected DVR (NSSC-DVR) has a relatively poor performance and is investigated in this paper. A new configuration is proposed and implemented for NSSC-DVR to enhance its performance in compensating (un)symmetrical deep and long voltage sags and mitigate voltage harmonics. The enhanced NSSC-DVR model includes a three-phase half-bridge semi-controlled network-side-shunt-connected rectifier and a three-phase full-bridge series-connected inverter implemented with a back-to-back configuration through a bidirectional buck-boost converter. The network-side-shunt-connected rectifier is employed to inject/draw the required energy by NSSC-DVR to restore the load voltage to its pre-fault value under sag/swell conditions. The buck-boost converter is responsible for maintaining the DC-link voltage of the series-connected inverter at its designated value in order to improve the NSSC-DVR capability in compensating deep and long voltage sags/swells. The full-bridge series-connected inverter permits to compensate unbalance voltage sags containing zero-sequence component. The harmonic compensation of the load voltage is achieved by extracting harmonics from the distorted network voltage using an artificial neural network (ANN) method called adaptive linear neuron (Adaline) strategy. Detailed simulations are performed by SIMULINK/MATLAB software for six case studies to verify the highly robustness of the proposed NSSC-DVR model under various conditions.

High power density dc-to-dc converters for aerospace applications

NASA Technical Reports Server (NTRS)

Divan, Deepakraj M.

1990-01-01

Three dc-to-dc converter topologies aimed at high-power high-frequency applications are introduced. Major system parasitics, namely, the leakage inductance of the transformer and the device output capacitance are efficiently utilized. Of the three circuits, the single-phase and three-phase versions of the dual active bridge topology demonstrate minimal stresses, better utilization of the transformer, bidirectional, and buck-boost modes of operation. All circuits operate at a constant switching frequency, thus simplifying design of the reactive elements. The power transfer characteristics and soft-switching regions on the Vout-Iout plane are identified. Two coaxial transformers with different cross-sections were built for a rating of 50 kVA. Based on the single-phase dual active bridge topology, a 50 kW, 50 kHz converter operating at an input voltage of 200 Vdc and an output voltage of 1600 Vdc was fabricated. Characteristics of current-fed output make the dual active bridge topologies amenable to paralleling and hence extension to megawatt power levels. Projections to a 1 MW system operating from a 500 Vdc input, at an output voltage of 10 kVdc and a switching frequency of 50 kHz, using MOS-controlled thyristors, coaxially wound transformers operating at three times the present current density with cooling, and multilayer ceramic capacitors, suggests an overall power density of 0.075 to 0.08 kg/kW and an overall efficiency of 96 percent.

Closed Loop Fuzzy Logic Controlled PV Based Cascaded Boost Five-Level Inverter System

NASA Astrophysics Data System (ADS)

Revana, Guruswamy; Kota, Venkata Reddy

2018-04-01

Recent developments in intelligent control methods and power electronics have produced PV based DC to AC converters related to AC drives. Cascaded boost converter and inverter find their way in interconnecting PV and Induction Motor. This paper deals with digital simulation and implementation of closed loop controlled five-level inverter based Photo-Voltaic (PV) system. The objective of this work is to reduce the harmonics using Multi Level Inverter based system. The DC output from the PV panel is boosted using cascaded-boost-converters. The DC output of these cascaded boost converters is applied to the bridges of the cascaded inverter. The AC output voltage is obtained by the series cascading of the output voltage of the two inverters. The investigations are done with Induction motor load. Cascaded boost-converter is proposed in the present work to produce the required DC Voltage at the input of the bridge inverter. A simple FLC is applied to CBFLIIM system. The FLC is proposed to reduce the steady state error. The simulation results are compared with the hardware results. The results of the comparison are made to show the improvement in dynamic response in terms of settling time and steady state error. Design procedure and control strategy are presented in detail.

Closed Loop Fuzzy Logic Controlled PV Based Cascaded Boost Five-Level Inverter System

NASA Astrophysics Data System (ADS)

Revana, Guruswamy; Kota, Venkata Reddy

2017-12-01

Recent developments in intelligent control methods and power electronics have produced PV based DC to AC converters related to AC drives. Cascaded boost converter and inverter find their way in interconnecting PV and Induction Motor. This paper deals with digital simulation and implementation of closed loop controlled five-level inverter based Photo-Voltaic (PV) system. The objective of this work is to reduce the harmonics using Multi Level Inverter based system. The DC output from the PV panel is boosted using cascaded-boost-converters. The DC output of these cascaded boost converters is applied to the bridges of the cascaded inverter. The AC output voltage is obtained by the series cascading of the output voltage of the two inverters. The investigations are done with Induction motor load. Cascaded boost-converter is proposed in the present work to produce the required DC Voltage at the input of the bridge inverter. A simple FLC is applied to CBFLIIM system. The FLC is proposed to reduce the steady state error. The simulation results are compared with the hardware results. The results of the comparison are made to show the improvement in dynamic response in terms of settling time and steady state error. Design procedure and control strategy are presented in detail.

A Fully Directional Universal Power Electronic Interface for EV, HEV, and PHEV Applications

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

Onar, Omer C

2012-01-01

This study focuses on a universal power electronic interface that can be utilized in any type of the electric vehicles, hybrid electric vehicles, and plug-in hybrid electric vehicles (PHEVs). Basically, the proposed converter interfaces the energy storage device of the vehicle with the motor drive and the external charger, in case of PHEVs. The proposed converter is capable of operating in all directions in buck or boost modes with a noninverted output voltage (positive output voltage with respect to the input) and bidirectional power flow.

Bucking the Trend: Is Ethnoracial Diversity Declining in American Communities?

PubMed Central

Lee, Barrett A.; Hughes, Lauren A.

2015-01-01

Although increasing diversity at the national scale is a well-documented trend, substantial variation in patterns of ethnoracial change occurs across American communities. Our research considers one theoretically implied path: that some communities are ‘bucking the trend’, becoming more homogeneous over time. Using 1980 through 2010 decennial census data, we calculate panethnic (five-group) entropy index scores to measure the magnitude of diversity for nearly 11,000 census-defined places. Our results indicate that while certain places reach their diversity peak in 1980 or 1990, they are few in number. Moreover, they experience a variety of post-peak trajectories other than monotonic diversity decline. Decreasing diversity is concentrated in the South and West, among places with higher levels of diversity and larger proportions of Hispanic or black residents at the beginning of the study period. These places exhibit complex shifts in racial-ethnic structure, but Hispanic succession predominates. PMID:26023247

Predicted sex ratio of juvenile Hawksbill Seaturtles inhabiting Buck Island Reef national monument, U.S. Virgin Islands

USGS Publications Warehouse

Geis, A.; Wibbels, T.; Phillips, B.; Hillis-Starr, Z.; Meylan, A.; Meylan, P.; Diez, C.; Van Dam, R.

2003-01-01

Hawksbill Seaturtles have temperature-dependent sex determination. As such, the resulting sex ratios are of conservational and ecological significance. Buck Island Reef is an interesting location for sex ratio studies since it represents a natural and unexploited foraging ground for hawksbills in the Caribbean. To examine sex ratios, blood samples were obtained from juvenile Hawksbill Seaturtles captured on Buck Island Reef over a four-year period. We used a radioimmunoassay to determine testosterone levels in those samples and compared those values to testosterone levels of juvenile hawksbills from the Caribbean whose sex has been verified by laparoscopy. The results of this study reveal a significantly female-biased sex ratio (approximately 80% female) occurs in this juvenile aggregation inhabiting Buck Island Reef.

Pegasus power system facility upgrades

NASA Astrophysics Data System (ADS)

Lewicki, B. T.; Kujak-Ford, B. A.; Winz, G. R.

2008-11-01

Two key Pegasus systems have been recently upgraded: the Ohmic-transformer IGCT bridge control system, and the plasma-gun injector power system. The Ohmic control system contains two new microprocessor controlled components to provide an interface between the PWM controller and the IGCT bridges. An interface board conditions the command signals from the PWM controller. A splitter/combiner board routes the conditioned PWM commands to an array of IGCT bridges and interprets IGCT bridge status. This system allows for any PWM controller to safely control IGCT bridges. Future developments will include a transition to a polyphasic bridge control. This will allow for 3 to 4 times the present pulse length and provide a much higher switching frequency. The plasma gun injector system now includes active current feedback control on gun bias current via PWM buck type power supplies. Near term goals include a doubling or tripling of the applied bias voltage. Future arc bias system power supplies may include a simpler boost type system which will allow access to even higher voltages using existing low voltage energy storage systems.

FET commutated current-FED inverter

NASA Technical Reports Server (NTRS)

Rippel, Wally E. (Inventor); Edwards, Dean B. (Inventor)

1983-01-01

A shunt switch comprised of a field-effect transistor (Q.sub.1) is employed to commutate a current-fed inverter (10) using thyristors (SCR1, SCR2) or bijunction transistors (Q.sub.2, Q.sub.3) in a full bridge (1, 2, 3, 4) or half bridge (5, 6) and transformer (T.sub.1) configuration. In the case of thyristors, a tapped inverter (12) is employed to couple the inverter to a dc source to back bias the thyristors during commutation. Alternatively, a commutation power supply (20) may be employed for that purpse. Diodes (D.sub.1, D.sub.2) in series with some voltage dropping element (resistor R.sub.12 or resistors R.sub.1, R.sub.2 or Zener diodes D.sub.4, D.sub.5) are connected in parallel with the thyristors in the half bridge and transformer configuration to assure sharing the back bias voltage. A clamp circuit comprised of a winding (18) negatively coupled to the inductor and a diode (D.sub.3) return stored energy from the inductor to the power supply for efficient operation with buck or boost mode.

A Low Input Current and Wide Conversion Ratio Buck Regulator with 75% Efficiency for High-Voltage Triboelectric Nanogenerators

NASA Astrophysics Data System (ADS)

Luo, Li-Chuan; Bao, De-Chun; Yu, Wu-Qi; Zhang, Zhao-Hua; Ren, Tian-Ling

2016-01-01

It is meaningful to research the Triboelectric Nanogenerators (TENG), which can create electricity anywhere and anytime. There are many researches on the structures and materials of TENG to explain the phenomenon that the maximum voltage is stable and the current is increasing. The output voltage of the TENG is high about 180-400 V, and the output current is small about 39 μA, which the electronic devices directly integration of TENG with Li-ion batteries will result in huge energy loss due to the ultrahigh TENG impedance. A novel interface circuit with the high-voltage buck regulator for TENG is introduced firstly in this paper. The interface circuit can transfer the output signal of the TENG into the signal fit to a lithium ion battery. Through the circuit of the buck regulator, the average output voltage is about 4.0 V and the average output current is about 1.12 mA. Further, the reliability and availability for the lithium ion battery and the circuit are discussed. The interface circuit is simulated using the Cadence software and verified through PCB experiment. The buck regulator can achieve 75% efficiency for the High-Voltage TENG. This will lead to a research hot and industrialization applications.

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

Kim, Hyeokjin; Chen, Hua; Maksimovic, Dragan

An experimental 30 kW boost composite converter is described in this paper. The composite converter architecture, which consists of a buck module, a boost module, and a dual active bridge module that operates as a DC transformer (DCX), leads to substantial reductions in losses at partial power points, and to significant improvements in weighted efficiency in applications that require wide variations in power and conversion ratio. A comprehensive loss model is developed, accounting for semiconductor conduction and switching losses, capacitor losses, as well as dc and ac losses in magnetic components. Based on the developed loss model, the module andmore » system designs are optimized to maximize efficiency at a 50% power point. Experimental results for the 30 kW prototype demonstrate 98.5%peak efficiency, very high efficiency over wide ranges of power and voltage conversion ratios, as well as excellent agreements between model predictions and measured efficiency curves.« less

Modeling, Development and Control of Multilevel Converters for Power System Application =

NASA Astrophysics Data System (ADS)

Vahedi, Hani

The main goal of this project is to develop a multilevel converter topology to be useful in power system applications. Although many topologies are introduced rapidly using a bunch of switches and isolated dc sources, having a single-dc-source multilevel inverter is still a matter of controversy. In fact, each isolated dc source means a bulky transformer and a rectifier that have their own losses and costs forcing the industries to avoid entering in this topic conveniently. On the other hand, multilevel inverters topologies with single-dc-source require associated controllers to regulate the dc capacitors voltages in order to have multilevel voltage waveform at the output. Thus, a complex controller would not interest investors properly. Consequently, developing a single-dc-source multilevel inverter topology along with a light and reliable voltage control is still a challenging topic to replace the 2-level inverters in the market effectively. The first effort in this project was devoted to the PUC7 inverter to design a simple and yet efficient controller. A new modelling is performed on the PUC7 inverter and it has been simplified to first order system. Afterwards, a nonlinear cascaded controller is designed and applied to regulate the capacitor voltage at 1/3 of the DC source amplitude and to generate 7 identical voltage levels at the output supplying different type of loads such as RL or rectifier harmonic ones. In next work, the PUC5 topology is proposed as a remedy to the PUC7 that requires a complicated controller to operate properly. The capacitor voltage is regulated at half of dc source amplitude to generate 5 voltage levels at the output. Although the 7-level voltage waveform is replaced by a 5-level one in PUC5 topology, it is shown that the PUC5 needs a very simple and reliable voltage balancing technique due to having some redundant switching states. Moreover, a sensor-less voltage balancing technique is designed and implemented on the PUC5 inverter successfully to work in both stand-alone and gridconnected mode of operation. Eventually, a modified configuration of the PUC5 topology is presented to work as a buck PFC rectifier. The internal performance of the rectifier is like a buck converter to generate stepped down DC voltages at the two output terminals while the grid sees a boost converter externally. As well, a decoupled voltage/current controller is designed and applied to balance the output voltages identically and synchronize the input current with grid voltage to have a PFC operation acceptably. A power balance analysis is done to show the load variation range limit. All the theoretical and simulation studies are validated by experimental results completely.

A Study of 4-level DC-DC Boost Inverter with Passive Component Reduction Consideration

NASA Astrophysics Data System (ADS)

Kasiran, A. N.; Ponniran, A.; Harimon, M. A.; Hamzah, H. H.

2018-04-01

This study is to analyze design principles of boost inductor and capacitor used in the 4-level DC-DC boost converter to realize size reduction of passive component referring to their attributes. The important feature of this circuit is that most of the boost-up energy is transferred from the capacitor-clamped to the output side which the small inductance can be used at the input side. The inductance of the boost inductor is designed by referring the inductor current ripple. On the other hand, the capacitance of the capacitor-clamped is designed by considering voltage stress on semiconductor devices and also the used switching frequency. Besides that, according to the design specifications, the required inductance in 4-level DC-DC boost converter is decreased compared to a conventional conventional DC-DC boost converter. Meanwhile, voltage stress on semiconductor device is depending on the maximum voltage ripple of the capacitor-clamped. A 50 W 4-level DC-DC boost converter prototype has been constructed. The results show that the inductor current ripple was 1.15 A when the inductors, 1 mH and 0.11 mH were used in the conventional and 4-level DC-DC boost converters, respectively. Thus, based on the experimental results, it shows that the reduction of passive components by referring to their attributes in 4-level DC-DC boost converter is achieved. Moreover, the decreasing of voltage stress on the semiconductor devices is an advantage for the selection of low ON-resistance of the devices which will contribute to the reduction of the semiconductor conduction loss. The integration result of boost converter and H-bridge inverter is also shown.

Fuzzy Current-Mode Control and Stability Analysis

NASA Technical Reports Server (NTRS)

Kopasakis, George

2000-01-01

In this paper a current-mode control (CMC) methodology is developed for a buck converter by using a fuzzy logic controller. Conventional CMC methodologies are based on lead-lag compensation with voltage and inductor current feedback. In this paper the converter lead-lag compensation will be substituted with a fuzzy controller. A small-signal model of the fuzzy controller will also be developed in order to examine the stability properties of this buck converter control system. The paper develops an analytical approach, introducing fuzzy control into the area of CMC.

Design of Power System Architectures for Small Spacecraft Systems

NASA Technical Reports Server (NTRS)

Momoh, James A.; Subramonian, Rama; Dias, Lakshman G.

1996-01-01

The objective of this research is to perform a trade study on several candidate power system architectures for small spacecrafts to be used in NASA's new millennium program. Three initial candidate architectures have been proposed by NASA and two other candidate architectures have been proposed by Howard University. Howard University is currently conducting the necessary analysis, synthesis, and simulation needed to perform the trade studies and arrive at the optimal power system architecture. Statistical, sensitivity and tolerant studies has been performed on the systems. It is concluded from present studies that certain components such as the series regulators, buck-boost converters and power converters can be minimized while retaining the desired functionality of the overall architecture. This in conjunction with battery scalability studies and system efficiency studies have enabled us to develop more economic architectures. Future studies will include artificial neural networks and fuzzy logic to analyze the performance of the systems. Fault simulation studies and fault diagnosis studies using EMTP and artificial neural networks will also be conducted.

Altitude and configuration of the potentiometric surface in Buckingham and Wrightstown townships, Bucks County, Pennsylvania, June 1992 through January 1993

USGS Publications Warehouse

McManus, B.C.; Schreffler, C.L.; Rowland, C.J.

1994-01-01

A map showing ground-water levels in Buckingham and Wrightstown Townships, Bucks County, Pennsylvania, was constructed from water levels measured in 251 wells and from 3 reported elevations of quarry sumps from June 1992 through January 1993. Observed water-level altitudes range from 459 feet above sea level along Burnt House Hill Road, south- west of Mechanicsville, to 10 feet above sea level along Swamp Road and Route 232, near Neshaminy Creek in Wrightstown Township.

Electronics drivers for high voltage dielectric electro active polymer (DEAP) applications

NASA Astrophysics Data System (ADS)

Zhang, Zhe; Andersen, Michael A. E.

2015-04-01

Dielectric electro active polymer (DEAP) can be used in actuation, sensing and energy harvesting applications, but driving the DEAP based actuators and generators has three main challenges from a power electronics standpoint, i.e. high voltage (around 2.5 kV), nonlinearity, and capacitive behavior. In this paper, electronics divers for heating valves, loud speakers, incremental motors, and energy harvesting are reviewed, studied and developed in accordance with their corresponding specifications. Due to the simplicity and low power capacity (below 10W), the reversible Fly-back converters with both magnetic and piezoelectric transformers are employed for the heating valve and incremental motor application, where only ON/OFF regulation is adopted for energy saving; as for DEAP based energy harvesting, the noisolated Buck/Boost converter is used, due to the system high power capacity (above 100W), but the voltage balancing across the series-connected high voltage IGBTs is a critical issue and accordingly a novel gate driver circuitry is proposed and equipped; due to the requirements of the audio products, such as low distortion and noise, the multi-level Buck converter based Class-D amplifier, because of its high control linearity, is implemented for the loud speaker applications. A synthesis among those converter topologies and control techniques is given; therefore, for those DEAP based applications, their diversity and similarity of electronics drivers, as well as the key technologies employed are analyzed. Therefore a whole picture of how to choose the proper topologies can be revealed. Finally, the design guidelines in order to achieve high efficiency and reliability are discussed.

Decentralized Interleaving of Paralleled Dc-Dc Buck Converters: Preprint

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

Johnson, Brian B; Rodriguez, Miguel; Sinha, Mohit

We present a decentralized control strategy that yields switch interleaving among parallel connected dc-dc buck converters without communication. The proposed method is based on the digital implementation of the dynamics of a nonlinear oscillator circuit as the controller. Each controller is fully decentralized, i.e., it only requires the locally measured output current to synthesize the pulse width modulation (PWM) carrier waveform. By virtue of the intrinsic electrical coupling between converters, the nonlinear oscillator-based controllers converge to an interleaved state with uniform phase-spacing across PWM carriers. To the knowledge of the authors, this work represents the first fully decentralized strategy formore » switch interleaving of paralleled dc-dc buck converters.« less

Formative assessment as a vehicle for changing classroom practice in a specific cultural context

NASA Astrophysics Data System (ADS)

Chen, Jingping

2015-09-01

In this commentary, I interpret Xinying Yin and Gayle Ann Buck's collaborative action research from a social-cultural perspective. Classroom implementation of formative assessment is viewed as interaction between this assessment method and the local learning culture. I first identify Yin and Buck's definition of the formative assessment, and then analyze the role of formative assessment in the change of local learning culture. Based on the practice of Yin and Buck I emphasize the significance of their "bottom up" strategy to the teachers' epistemological change. I believe that this strategy may provide practicable solutions to current Chinese educational problems as well as a means for science educators to shift toward systematic professional development.

Food safety aspects of primary environmental contaminants in the edible tissues of roe deer (Capreolus capreolus).

PubMed

Lehel, József; Zwillinger, Dóra; Bartha, András; Lányi, Katalin; Laczay, Péter

2017-11-01

The muscle, liver, kidney and fat samples of 20 roe deer of both sexes originating from a hunting area in central Hungary were investigated for the presence of heavy metals such as As, Cd, Hg and Pb, and their contents were evaluated for possible health risk to consumers. Both As and Hg were found at a level below the limit of detection (< 0.5 mg/kg wet weight) in all samples. The median of the measured Cd concentrations was significantly higher in both the kidney and the liver (p = 0.0011) of bucks than of does. In bucks, Cd levels exceeded the respective maximum limits laid down in the European legislation in four kidney and three muscle samples, whereas in does, the measured concentrations were below the respective limits in all samples. The detected amounts of Pb exceeded the maximum limits in the kidney of one buck and eight does, in the liver of two bucks and six does, in the muscle of six bucks and nine does, whereas in all fat tissues of both bucks and does. The concentration of Pb (p = 0.02) was significantly greater in the kidney of does compared to roebucks. Based on data obtained from the present study, the consumption of organs and tissues of the investigated roe deer could be objectionable from food-toxicological point of view and may pose risk to the high consumers of wild game due to their cadmium and lead contents.

Methods, systems and apparatus for controlling operation of two alternating current (AC) machines

DOEpatents

Gallegos-Lopez, Gabriel [Torrance, CA; Nagashima, James M [Cerritos, CA; Perisic, Milun [Torrance, CA; Hiti, Silva [Redondo Beach, CA

2012-02-14

A system is provided for controlling two AC machines. The system comprises a DC input voltage source that provides a DC input voltage, a voltage boost command control module (VBCCM), a five-phase PWM inverter module coupled to the two AC machines, and a boost converter coupled to the inverter module and the DC input voltage source. The boost converter is designed to supply a new DC input voltage to the inverter module having a value that is greater than or equal to a value of the DC input voltage. The VBCCM generates a boost command signal (BCS) based on modulation indexes from the two AC machines. The BCS controls the boost converter such that the boost converter generates the new DC input voltage in response to the BCS. When the two AC machines require additional voltage that exceeds the DC input voltage required to meet a combined target mechanical power required by the two AC machines, the BCS controls the boost converter to drive the new DC input voltage generated by the boost converter to a value greater than the DC input voltage.

Decentralized Interleaving of Paralleled Dc-Dc Buck Converters

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

Johnson, Brian B; Rodriguez, Miguel; Sinha, Mohit

We present a decentralized control strategy that yields switch interleaving among parallel-connected dc-dc buck converters. The proposed method is based on the digital implementation of the dynamics of a nonlinear oscillator circuit as the controller. Each controller is fully decentralized, i.e., it only requires the locally measured output current to synthesize the pulse width modulation (PWM) carrier waveform and no communication between different controllers is needed. By virtue of the intrinsic electrical coupling between converters, the nonlinear oscillator-based controllers converge to an interleaved state with uniform phase-spacing across PWM carriers. To the knowledge of the authors, this work presents themore » first fully decentralized strategy for switch interleaving in paralleled dc-dc buck converters.« less

77 FR 12323 - Draft Environmental Impact Statement for the General Management Plan, Buck Island Reef National...

Federal Register 2010, 2011, 2012, 2013, 2014

2012-02-29

...Pursuant to 42 U.S.C. 4332(2)(C) of the National Environmental Policy Act of 1969 and National Park Service (NPS) policy in Director's Order Number 2 (Park Planning) and Director's Order Number 12 (Conservation Planning, Environmental Impact Analysis, and Decision- making) the NPS announces the availability of a DEIS/GMP for Buck Island Reef National Monument, Virgin Islands. The document provides a framework for management, use, and development options for Buck Island Reef National Monument by the NPS for the next 15 to 20 years. It describes four management alternatives for consideration, including a No-Action Alternative that continues current management policies and the NPS's preferred alternative. The document analyzes the environmental impacts of the alternatives.

Improving fruit and vegetable consumption among low-income customers at farmers markets: Philly Food Bucks, Philadelphia, Pennsylvania, 2011.

PubMed

Young, Candace R; Aquilante, Jennifer L; Solomon, Sara; Colby, Lisa; Kawinzi, Mukethe A; Uy, Nicky; Mallya, Giridhar

2013-10-03

We evaluated whether Philly Food Bucks, a bonus incentive program at farmers markets, is associated with increased fruit and vegetable consumption and Supplemental Nutrition Assistance Program (SNAP) sales at farmers markets in low-income areas. A convenience sample of 662 customers at 22 farmers markets in low-income neighborhoods in Philadelphia, Pennsylvania, was surveyed via face-to-face interviews. Questions addressed shopping characteristics, self-reported change in fruit and vegetable consumption, whether customers tried new fruits or vegetables, use of Philly Food Bucks, and demographic information. Market-level SNAP sales and Philly Food Bucks redemption data were also collected to monitor sales patterns. Philly Food Bucks users were significantly more likely than nonusers to report increasing fruit and vegetable consumption (OR, 2.4; 95% CI, 1.6-3.7; P < .001) and to report trying new fruits or vegetables (OR 1.8; 95% CI, 1.2-2.7; P = .006). At the market level, average SNAP sales more than doubled at farmers markets in low-income areas in the first 2 years of the Philly Food Bucks program. At the city's largest farmers market in a low-income area, the program was associated with an almost 5-fold higher increase in annual SNAP sales compared with baseline. Results from this study demonstrate that a bonus incentive program tied to SNAP was associated with self-reported increases in fruit and vegetable consumption and increased SNAP sales at participating farmers markets in low-income communities. More research is warranted to evaluate the long-term impact of bonus incentives on farmers market use, dietary behaviors, and health outcomes.

Analysis of a PWM Resonant Buck Chopper for Use as a Ship Service Converter Module

DTIC Science & Technology

1999-01-01

zonal architecture [2] has a number of advantages over the current radial distribution architecture. The radial network includes generators supplying...Several representative topologies are considered in this section. The literature is replete with softswitching dc-dc converter topologies and control...differs from a conventional PWM buck by the addition of a resonant network consisting of inductor Lr, capacitor Q, an auxiliary switch Sr, an auxiliary

Resident areas and migrations of female green turtles nesting at Buck Island Reef National Monument, St. Croix, U.S. Virgin Islands

USGS Publications Warehouse

Hart, Kristen M.; Iverson, Autumn; Benscoter, Allison M.; Fujisaki, Ikuko; Cherkiss, Michael S.; Pollock, Clayton; Lundgren, Ian; Hillis-Starr, Zandy

2017-01-01

Satellite tracking in marine turtle studies can reveal much about their spatial use of breeding areas, migration zones, and foraging sites. We assessed spatial habitat-use patterns of 10 adult female green turtles (Chelonia mydas) nesting at Buck Island Reef National Monument, U.S. Virgin Islands (BIRNM) from 2011 – 2014. Turtles ranged in size from 89.0 – 115.9 cm CCL (mean + SD = 106.8 + 7.7 cm). The inter-nesting period across all turtles ranged from 31 July to 4 November, and sizes of the 50% core-use areas during inter-nesting ranged from 4.2 – 19.0 km2. Inter-nesting core-use areas were located up to1.4 km from shore and had bathymetry values ranging from -17.0 to -13.0 m. Seven of the ten turtles remained locally resident after the nesting season. Five turtles (50%) foraged around Buck Island, two foraged around the island of St. Croix, and the other three (30%) made longer-distance migrations to Antigua, St. Kitts & Nevis, and Venezuela. Further, five turtles had foraging centroids within protected areas. Delineating spatial areas and identifying temporal periods of nearshore habitat-use can be useful for natural resource managers with responsibility for overseeing vulnerable habitats and protected marine turtle populations.

Sterile Protection against Plasmodium knowlesi in Rhesus Monkeys from a Malaria Vaccine: Comparison of Heterologous Prime Boost Strategies

PubMed Central

Jiang, George; Shi, Meng; Conteh, Solomon; Richie, Nancy; Banania, Glenna; Geneshan, Harini; Valencia, Anais; Singh, Priti; Aguiar, Joao; Limbach, Keith; Kamrud, Kurt I.; Rayner, Jonathan; Smith, Jonathan; Bruder, Joseph T.; King, C. Richter; Tsuboi, Takafumi; Takeo, Satoru; Endo, Yaeta; Doolan, Denise L.; Richie, Thomas L.; Weiss, Walter R.

2009-01-01

Using newer vaccine platforms which have been effective against malaria in rodent models, we tested five immunization regimens against Plasmodium knowlesi in rhesus monkeys. All vaccines included the same four P. knowlesi antigens: the pre-erythrocytic antigens CSP, SSP2, and erythrocytic antigens AMA1, MSP1. We used four vaccine platforms for prime or boost vaccinations: plasmids (DNA), alphavirus replicons (VRP), attenuated adenovirus serotype 5 (Ad), or attenuated poxvirus (Pox). These four platforms combined to produce five different prime/boost vaccine regimens: Pox alone, VRP/Pox, VRP/Ad, Ad/Pox, and DNA/Pox. Five rhesus monkeys were immunized with each regimen, and five Control monkeys received a mock vaccination. The time to complete vaccinations was 420 days. All monkeys were challenged twice with 100 P. knowlesi sporozoites given IV. The first challenge was given 12 days after the last vaccination, and the monkeys receiving the DNA/Pox vaccine were the best protected, with 3/5 monkeys sterilely protected and 1/5 monkeys that self-cured its parasitemia. There was no protection in monkeys that received Pox malaria vaccine alone without previous priming. The second sporozoite challenge was given 4 months after the first. All 4 monkeys that were protected in the first challenge developed malaria in the second challenge. DNA, VRP and Ad5 vaccines all primed monkeys for strong immune responses after the Pox boost. We discuss the high level but short duration of protection in this experiment and the possible benefits of the long interval between prime and boost. PMID:19668343

Risky Business II: Finding Big Bucks. Panel IV.

ERIC Educational Resources Information Center

Appalachia, 1986

1986-01-01

Five panelists discuss alternatives to venture capital sources for Appalachian business expansion, new institutions created or supported by state and local governments to provide capital, and how businesses can best position themselves to take advantage of all capital sources. (NEC)

An Optimal Current Observer for Predictive Current Controlled Buck DC-DC Converters

PubMed Central

Min, Run; Chen, Chen; Zhang, Xiaodong; Zou, Xuecheng; Tong, Qiaoling; Zhang, Qiao

2014-01-01

In digital current mode controlled DC-DC converters, conventional current sensors might not provide isolation at a minimized price, power loss and size. Therefore, a current observer which can be realized based on the digital circuit itself, is a possible substitute. However, the observed current may diverge due to the parasitic resistors and the forward conduction voltage of the diode. Moreover, the divergence of the observed current will cause steady state errors in the output voltage. In this paper, an optimal current observer is proposed. It achieves the highest observation accuracy by compensating for all the known parasitic parameters. By employing the optimal current observer-based predictive current controller, a buck converter is implemented. The converter has a convergently and accurately observed inductor current, and shows preferable transient response than the conventional voltage mode controlled converter. Besides, costs, power loss and size are minimized since the strategy requires no additional hardware for current sensing. The effectiveness of the proposed optimal current observer is demonstrated experimentally. PMID:24854061

Women in History--Pearl Buck: An Advocate for Women and Children

ERIC Educational Resources Information Center

Watts, Lynette

2008-01-01

This article profiles Pearl Buck, an advocate for women's rights and minority children, an author of Chinese history, and a pioneer in many ways. Buck established the Welcome House in 1949 in order to help unadoptable children find families (Conn, 1996). In 1964, Buck founded the Pearl S. Buck Foundation, now Pearl S. Buck International, which…

Optimal tree-stem bucking of northeastern species of China

Treesearch

Jingxin Wang; Chris B. LeDoux; Joseph McNeel

2004-01-01

An application of optimal tree-stem bucking to the northeastern tree species of China is reported. The bucking procedures used in this region are summarized, which are the basic guidelines for the optimal bucking design. The directed graph approach was adopted to generate the bucking patterns by using the network analysis labeling algorithm. A computer-based bucking...

Design and experiment of vehicular charger AC/DC system based on predictive control algorithm

NASA Astrophysics Data System (ADS)

He, Guangbi; Quan, Shuhai; Lu, Yuzhang

2018-06-01

For the car charging stage rectifier uncontrollable system, this paper proposes a predictive control algorithm of DC/DC converter based on the prediction model, established by the state space average method and its prediction model, obtained by the optimal mathematical description of mathematical calculation, to analysis prediction algorithm by Simulink simulation. The design of the structure of the car charging, at the request of the rated output power and output voltage adjustable control circuit, the first stage is the three-phase uncontrolled rectifier DC voltage Ud through the filter capacitor, after by using double-phase interleaved buck-boost circuit with wide range output voltage required value, analyzing its working principle and the the parameters for the design and selection of components. The analysis of current ripple shows that the double staggered parallel connection has the advantages of reducing the output current ripple and reducing the loss. The simulation experiment of the whole charging circuit is carried out by software, and the result is in line with the design requirements of the system. Finally combining the soft with hardware circuit to achieve charging of the system according to the requirements, experimental platform proved the feasibility and effectiveness of the proposed predictive control algorithm based on the car charging of the system, which is consistent with the simulation results.

An energy-efficient, adiabatic electrode stimulator with inductive energy recycling and feedback current regulation.

PubMed

Arfin, Scott K; Sarpeshkar, Rahul

2012-02-01

In this paper, we present a novel energy-efficient electrode stimulator. Our stimulator uses inductive storage and recycling of energy in a dynamic power supply. This supply drives an electrode in an adiabatic fashion such that energy consumption is minimized. It also utilizes a shunt current-sensor to monitor and regulate the current through the electrode via feedback, thus enabling flexible and safe stimulation. Since there are no explicit current sources or current limiters, wasteful energy dissipation across such elements is naturally avoided. The dynamic power supply allows efficient transfer of energy both to and from the electrode and is based on a DC-DC converter topology that we use in a bidirectional fashion in forward-buck or reverse-boost modes. In an exemplary electrode implementation intended for neural stimulation, we show how the stimulator combines the efficiency of voltage control and the safety and accuracy of current control in a single low-power integrated-circuit built in a standard .35 μm CMOS process. This stimulator achieves a 2x-3x reduction in energy consumption as compared to a conventional current-source-based stimulator operating from a fixed power supply. We perform a theoretical analysis of the energy efficiency that is in accord with experimental measurements. This theoretical analysis reveals that further improvements in energy efficiency may be achievable with better implementations in the future. Our electrode stimulator could be widely useful for neural, cardiac, retinal, cochlear, muscular and other biomedical implants where low power operation is important.

THE BUCK HILL FALLS REPORT, THE CHANGING NATURE AND SCOPE OF THE SCHOOL AND LIBRARY MARKET. ARE NEW MARKETING TECHNIQUES NEEDED. A CONFERENCE SPONSORED BY THE SCHOOL AND LIBRARY PROMOTION AND MARKETING COMMITTEE (BUCK HILL FALLS, APRIL 27-29,1966).

ERIC Educational Resources Information Center

SCRIBNER, CHARLES, JR.

PUBLISHERS, LIBRARIANS, AND EDUCATORS MET TO DISCUSS THE CURRENT SCHOOL AND LIBRARY MARKET FOR BOOKS AND OTHER INSTRUCTIONAL MATERIALS IN AN EFFORT TO INCREASE UNDERSTANDING OF THEIR RESPECTIVE ROLES IN MEETING THE GREATER DEMANDS MADE UPON THEM BY THE ADOPTION OF IMPROVED EDUCATION AS A NATIONAL POLICY. AFTER AN EXAMINATION OF FEDERAL EDUCATIONAL…

Correlation of biochemical constituents of seminal plasma with semen quality in Teddy goat (Capra hircus) bucks.

PubMed

Umar, S; Ahmad, M; Ahmad, I; Zubair, M; Umar, Z; Qureshi, A S; Manzoor, A; Murtaza, A; Shaukat, A

2018-04-01

This study was planned to determine the relationship between semen quality parameters and the levels of biochemical constituents of seminal plasma of Teddy (Capra hircus) buck semen. For this purpose, semen ejaculates were collected from five mature healthy Teddy bucks. All the experimental bucks were kept under natural environmental conditions. Semen was collected twice in a week for the duration of 6 weeks by Artificial Vagina (AV) in the breeding season (February-April). Two successive ejaculates of single buck were pooled at time of collection, and a total of 60 semen samples were processed for semen analysis. Sperm per cent motility, sperm concentration, dead sperm percentage, morphological abnormal spermatozoa, plasma membrane integrity were correlated with biochemical constituents of seminal plasma. The mean per cent motility (89.18% ± 0.37%), sperm concentration (1.86 ± 0.04 × 10 9 /ml), dead sperm percentage (8.08% ± 0.29%), morphological abnormal spermatozoa (6.05% ± 0.29%) and plasma membrane integrity (88.22% ± 0.34%) were recorded. The seminal plasma contained Na + (144.12 ± 1.59 mEq/L), K + (27.38 ± 0.49 mEq/L), Cl - (65.73 ± 0.45 mEq/L), Ca ++ (9.34 ± 0.22 mg/dl), P (19.32 ± 0.97 mg/dl), aspartate aminotransferase (AST; 26.48 ± 1.30 IU/L), alanine aminotransferase (ALT; 168.47 ± 5.18 IU/L), lactate dehydrogenase (LDH; 215.98 ± 6.06 IU/L), albumin (1.90 ± 0.10 g/dl), globulins (2.08 ± 0.11 g/dl) and total protein (3.98 ± 0.20 g/dl). The collected data were analysed by applying Pearson's correlation coefficients. Dead sperm percentage had negative correlation with sodium (r = -.278, p < .05), albumin (r = -.294, p < .05), globulin (r = -.266, p < .05) and total protein (r = -.295, p < .05). Phosphorus was negatively associated with sperm concentration (r = -.262, p < .05). AST was negatively correlated with plasma membrane integrity (r = -.292, p < .05). It was concluded that most of the semen quality parameters of Teddy bucks were positively correlated with biochemical constituents, but opposite trends were found in case of dead sperm percentage. The seminal biochemical constituents dynamically interact with each other. © 2017 Blackwell Verlag GmbH.

Elimination of current spikes in buck power converters

NASA Technical Reports Server (NTRS)

Mclyman, W. T. (Inventor)

1981-01-01

Current spikes in a buck power converter due to commutating diode turn-off time are eliminated by using a tapped inductor in the converter with the tap connected to the switching transistor. The commutating diode is not in the usual place, but is instead connected to conduct current from one end of the tapped inductor remote from the load during the interval in which the transistor is not conducting. In the case of a converter having a center-tapped (primary and secondary) transformer between two switching power transistors operated in a push-pull mode and two rectifying diodes in the secondary circuit, current spikes due to transformer saturation are also eliminated by using a tapped inductor in the converter with the tap connected to the rectifying diodes and a diode connected to conduct current from one end of the tapped inductor remote from the load during the interval in which the transistors are not conducting.

Hardware Implementation of Maximum Power Point Tracking for Thermoelectric Generators

NASA Astrophysics Data System (ADS)

Maganga, Othman; Phillip, Navneesh; Burnham, Keith J.; Montecucco, Andrea; Siviter, Jonathan; Knox, Andrew; Simpson, Kevin

2014-06-01

This work describes the practical implementation of two maximum power point tracking (MPPT) algorithms, namely those of perturb and observe, and extremum seeking control. The proprietary dSPACE system is used to perform hardware in the loop (HIL) simulation whereby the two control algorithms are implemented using the MATLAB/Simulink (Mathworks, Natick, MA) software environment in order to control a synchronous buck-boost converter connected to two commercial thermoelectric modules. The process of performing HIL simulation using dSPACE is discussed, and a comparison between experimental and simulated results is highlighted. The experimental results demonstrate the validity of the two MPPT algorithms, and in conclusion the benefits and limitations of real-time implementation of MPPT controllers using dSPACE are discussed.

Adaptive capability as indicated by behavioral and physiological responses, plasma HSP70 level, and PBMC HSP70 mRNA expression in Osmanabadi goats subjected to combined (heat and nutritional) stressors.

PubMed

Shilja, Shaji; Sejian, V; Bagath, M; Mech, A; David, C G; Kurien, E K; Varma, Girish; Bhatta, Raghavendra

2016-09-01

A study was conducted to assess the impact of heat and nutritional stress simultaneously on the adaptive capability as indicated by behavioral and physiological responses, plasma heat shock protein 70 (HSP70) level, and peripheral blood mononuclear cells (PBMC) HSP70 gene expression in goats. Twenty-four adult Osmanabadi bucks (average body weight (BW) 16.0 kg) were used in the present study. The bucks were divided into four groups viz., C (n = 6; control), HS (n = 6; heat stress), NS (n = 6; nutritional stress), and CS (n = 6; combined stress). The study was conducted for a period of 45 days. C and HS bucks had ad libitum access to their feed while NS and CS bucks were under restricted feed (30 % intake of C bucks) to induce nutritional stress. The HS and CS bucks were exposed to solar radiation for 6 h a day between 10:00 a.m. and 4:00 p.m. to induce heat stress. The data was analyzed using repeated measures analysis of variance. The standing time differed significantly (P < 0.01) between ad libitum fed groups (C and HS) and restricted feeding groups (NS and CS). The highest (P < 0.01) lying time was recorded in the CS group while the lowest in the C and HS groups. The highest (P < 0.01) drinking frequency was also recorded in the CS group. Water intake recorded was significantly (P < 0.01) higher in both the HS and CS groups. The highest respiration rate (RR), pulse rate (PR), and rectal temperature (RT) during the afternoon were also recorded in the CS group. Further, skin temperature of the head, flank, and scrotum during the afternoon was also higher (P < 0.01) in the CS group. In addition, both plasma HSP70 concentration and PBMC HSP70 messenger RNA (mRNA) transcript expression were also significantly (P < 0.01) higher in the CS group. It can be concluded from this study that when two stressors occur simultaneously, they may have severe impact on adaptive capabilities of Osmanabadi bucks as compared to that would occur individually. Further, the study indicated that lying time, drinking frequency, RR, RT, plasma HSP70, and PBMC HSP70 gene expression may act as ideal biological markers for assessing the impact of CS on adaptive capabilities in bucks.

Adaptive capability as indicated by behavioral and physiological responses, plasma HSP70 level, and PBMC HSP70 mRNA expression in Osmanabadi goats subjected to combined (heat and nutritional) stressors

NASA Astrophysics Data System (ADS)

Shilja, Shaji; Sejian, V.; Bagath, M.; Mech, A.; David, C. G.; Kurien, E. K.; Varma, Girish; Bhatta, Raghavendra

2016-09-01

A study was conducted to assess the impact of heat and nutritional stress simultaneously on the adaptive capability as indicated by behavioral and physiological responses, plasma heat shock protein 70 (HSP70) level, and peripheral blood mononuclear cells (PBMC) HSP70 gene expression in goats. Twenty-four adult Osmanabadi bucks (average body weight (BW) 16.0 kg) were used in the present study. The bucks were divided into four groups viz., C ( n = 6; control), HS ( n = 6; heat stress), NS ( n = 6; nutritional stress), and CS ( n = 6; combined stress). The study was conducted for a period of 45 days. C and HS bucks had ad libitum access to their feed while NS and CS bucks were under restricted feed (30 % intake of C bucks) to induce nutritional stress. The HS and CS bucks were exposed to solar radiation for 6 h a day between 10:00 a.m. and 4:00 p.m. to induce heat stress. The data was analyzed using repeated measures analysis of variance. The standing time differed significantly ( P < 0.01) between ad libitum fed groups (C and HS) and restricted feeding groups (NS and CS). The highest ( P < 0.01) lying time was recorded in the CS group while the lowest in the C and HS groups. The highest ( P < 0.01) drinking frequency was also recorded in the CS group. Water intake recorded was significantly ( P < 0.01) higher in both the HS and CS groups. The highest respiration rate (RR), pulse rate (PR), and rectal temperature (RT) during the afternoon were also recorded in the CS group. Further, skin temperature of the head, flank, and scrotum during the afternoon was also higher ( P < 0.01) in the CS group. In addition, both plasma HSP70 concentration and PBMC HSP70 messenger RNA (mRNA) transcript expression were also significantly ( P < 0.01) higher in the CS group. It can be concluded from this study that when two stressors occur simultaneously, they may have severe impact on adaptive capabilities of Osmanabadi bucks as compared to that would occur individually. Further, the study indicated that lying time, drinking frequency, RR, RT, plasma HSP70, and PBMC HSP70 gene expression may act as ideal biological markers for assessing the impact of CS on adaptive capabilities in bucks.

A computerized bucking trainer for optimally bucking hardwoods

Treesearch

Scott Noble; Blair Orr; Philip A. Araman; John Baumgras; James B. Pickens

2000-01-01

The bucking of hardwood stems constitutes the initial manufacturing decision for hardwood lumber production. Each bucking cut creates a log of fixed grade and scale. The grade and scale of each log created by the bucker determines the quantity and quality of potential lumber, which determines the value of the log within a given market. As a result, bucking decisions...

Production analysis of two tree-bucking and product-sorting methods for hardwoods

Treesearch

John E. Baumgras; Chris B. LeDoux

1989-01-01

This paper documents the results of a study to determine the cost and productivity of two tree-bucking and product-sorting methods used by West Virginia loggers harvesting three to four types of roundwood products. The methods include manual chainsaw bucking and bucking with a hydraulically powered chainsaw slasher. Results show that chain saw bucking of trees...

75 FR 16128 - Agency Forms Undergoing Paperwork Reduction Act Review

Federal Register 2010, 2011, 2012, 2013, 2014

2010-03-31

... Project Evaluation of Childhood Obesity Prevention and Control Initiative: New York City Health Bucks... Disease Control and Prevention (CDC). Background and Brief Description Childhood obesity is a major public health concern. One out of every five children is affected by overweight or obesity in the United States...

Performance and hemtochemical parameters of buck-kids fed concentrate partially replaced with tropical Piliostigma thonningii foliage.

PubMed

Olafadehan, Olurotimi A; Njidda, Ahmed A; Okunade, Sunday A; Salihu, Sarah O; Balogun, David O; Salem, Abdelfattah Z M

2018-02-01

Fifteen 5-month-old Red Sokoto buck-kids, (6.6 ± 0.71 kg body weight (BW)) randomly distributed into three groups of five animals per group, were used to study the effects of supplementary concentrate partially replaced with Piliostigma thonningii (PT) foliage on the growth performance, economic benefit and blood profile in a completely randomized design using analysis of variance. The goats in group 1 received 100% supplementary concentrates (PT0), groups 2 and 3 received 25% (PT25) and 50% (PT50), respectively, of concentrate replaced with an equal amount (dry matter basis) of Piliostigma foliage. The goats were fed a basal diet of threshed sorghum top (TST). Intake of concentrate, hemoglobin, mean corpuscular hemoglobin concentration, mean corpuscular hemoglobin, total feeding cost and cost/kg BW were greater (P < 0.05) for PT0 than for PT25 and PT50. Consumption of P. thonningii foliage was greater (P < 0.05) for PT50 relative to PT25. Tannin consumption of the treatment diets were greater (P < 0.05) than that of the control concentrate diet. Serum urea N reduced (P < 0.05) with increasing level of concentrate replacement, while serum glucose was higher (P < 0.05) in PT0 than in PT50. However, means of all blood measurements were within normal ranges for goats. Net benefit showed this rank order: PT0 < PT50 < PT25 (all P < 0.05). Both differential and relative benefits were higher (P < 0.05) for PT25 than for PT50. P. thonningii foliage can replace 50% of supplemental concentrate without impairing feed intake, growth performance and health of buck-kids. © 2017 Japanese Society of Animal Science.

Laboratory and Workplace Assessments of Rivet Bucking Bar Vibration Emissions

PubMed Central

McDowell, Thomas W.; Warren, Christopher; Xu, Xueyan S.; Welcome, Daniel E.; Dong, Ren G.

2016-01-01

Sheet metal workers operating rivet bucking bars are at risk of developing hand and wrist musculoskeletal disorders associated with exposures to hand-transmitted vibrations and forceful exertions required to operate these hand tools. New bucking bar technologies have been introduced in efforts to reduce workplace vibration exposures to these workers. However, the efficacy of these new bucking bar designs has not been well documented. While there are standardized laboratory-based methodologies for assessing the vibration emissions of many types of powered hand tools, no such standard exists for rivet bucking bars. Therefore, this study included the development of a laboratory-based method for assessing bucking bar vibrations which utilizes a simulated riveting task. With this method, this study evaluated three traditional steel bucking bars, three similarly shaped tungsten alloy bars, and three bars featuring spring-dampeners. For comparison the bucking bar vibrations were also assessed during three typical riveting tasks at a large aircraft maintenance facility. The bucking bars were rank-ordered in terms of unweighted and frequency-weighted acceleration measured at the hand-tool interface. The results suggest that the developed laboratory method is a reasonable technique for ranking bucking bar vibration emissions; the lab-based riveting simulations produced similar rankings to the workplace rankings. However, the laboratory-based acceleration averages were considerably lower than the workplace measurements. These observations suggest that the laboratory test results are acceptable for comparing and screening bucking bars, but the laboratory measurements should not be directly used for assessing the risk of workplace bucking bar vibration exposures. The newer bucking bar technologies exhibited significantly reduced vibrations compared to the traditional steel bars. The results of this study, together with other information such as rivet quality, productivity, tool weight, comfort, worker acceptance, and initial cost can be used to make informed bucking bar selections. PMID:25381185

Laboratory and workplace assessments of rivet bucking bar vibration emissions.

PubMed

McDowell, Thomas W; Warren, Christopher; Xu, Xueyan S; Welcome, Daniel E; Dong, Ren G

2015-04-01

Sheet metal workers operating rivet bucking bars are at risk of developing hand and wrist musculoskeletal disorders associated with exposures to hand-transmitted vibrations and forceful exertions required to operate these hand tools. New bucking bar technologies have been introduced in efforts to reduce workplace vibration exposures to these workers. However, the efficacy of these new bucking bar designs has not been well documented. While there are standardized laboratory-based methodologies for assessing the vibration emissions of many types of powered hand tools, no such standard exists for rivet bucking bars. Therefore, this study included the development of a laboratory-based method for assessing bucking bar vibrations which utilizes a simulated riveting task. With this method, this study evaluated three traditional steel bucking bars, three similarly shaped tungsten alloy bars, and three bars featuring spring-dampeners. For comparison the bucking bar vibrations were also assessed during three typical riveting tasks at a large aircraft maintenance facility. The bucking bars were rank-ordered in terms of unweighted and frequency-weighted acceleration measured at the hand-tool interface. The results suggest that the developed laboratory method is a reasonable technique for ranking bucking bar vibration emissions; the lab-based riveting simulations produced similar rankings to the workplace rankings. However, the laboratory-based acceleration averages were considerably lower than the workplace measurements. These observations suggest that the laboratory test results are acceptable for comparing and screening bucking bars, but the laboratory measurements should not be directly used for assessing the risk of workplace bucking bar vibration exposures. The newer bucking bar technologies exhibited significantly reduced vibrations compared to the traditional steel bars. The results of this study, together with other information such as rivet quality, productivity, tool weight, comfort, worker acceptance, and initial cost can be used to make informed bucking bar selections. Published by Oxford University Press on behalf of the British Occupational Hygiene Society 2014.

Continuous contact with females in estrus throughout the year enhances testicular activity and improves seminal traits of male goats.

PubMed

Giriboni, Julia; Lacuesta, Lorena; Ungerfeld, Rodolfo

2017-01-01

The "female effect" consists in the stimulation of males' reproductive activity by different signals emitted by females. This stimulation leads to endocrine and behavioral changes that may modify the seasonal pattern of male ruminants. The aims of this experiment were (1) to describe the local reproductive seasonal pattern of Gabon bucks and (2) to determine if continuous chemical, auditory, and visual contact with does in estrus enhances bucks' testicular activity and improves seminal traits throughout the year and modify their seasonal pattern. We used 16 adult Gabon bucks assigned to two experimental groups: nine bucks remained continuously isolated from females (isolated bucks, group IB) and seven bucks were in continuous chemical, auditory, and visual contact through a fence line with does in estrus (stimulated bucks, group SB). During 13 months, scrotal circumference and testosterone concentration were measured weekly and testicular echogenicity was measured every 2 weeks. Also, sperm motility mass and percentage of abnormal spermatozoa were determined, and sperm concentration and total number of motile spermatozoa were calculated every 2 weeks. Testicular echogenicity was greater in IB than that in SB bucks (P < 0.0001), but there were no differences in scrotal circumference. Overall, testosterone concentration was greater in IB than that in SB bucks (P = 0.04), but from late winter to mid-summer, when testosterone concentration presented basal concentrations, SB bucks had greater values than IB bucks (P = 0.004). Sperm concentration (P = 0.05) and sperm mass motility (P = 0.01) were greater in SB than that in IB bucks, and the total number of progressive motile spermatozoa tended to be greater in SB than in that IB bucks (P = 0.1). The percentage of abnormal spermatozoa was lower in SB than in IB bucks in several time points (P < 0.0001). Testicular and seminal traits were better from the end of the spring until mid-autumn. We concluded that does in estrus stimulated bucks' testicular activity, including better seminal quality and a greater increase of testicular fluid content than bucks isolated from females. However, the general seasonal pattern was not modified by stimulation with does in estrus. Copyright © 2016 Elsevier Inc. All rights reserved.

Does a prosocial-selfish distinction help explain the biological affects? Comment on Buck (1999).

PubMed

Gray, Jeremy R

2002-10-01

R. Buck (1999) argued that a conceptual distinction between prosocial and selfish motivation is necessary to understand the biological affects (consciously experienced feelings and desires having an innate neurochemical basis). However, at a biological level of analysis, a prosocial-selfish distinction is doubtful empirically and conceptually. For this reason, Buck's proposed typology of biological affects is unclear. Moreover, a prosocial-selfish distinction is not necessary to explain hemispheric differences in brain activity associated with affect. In contrast, an approach-withdrawal distinction explains some data uniquely well, although numerous exceptions imply that simple models are inadequate. To extend hemispheric models of experienced emotion, a prosocial-selfish distinction is unlikely to be explanatory, whereas an alternative account based on a distinction between verbal and nonverbal working memory may be useful.

Dramatically Polarized Opinion on the Role of Brachytherapy Boost in Management of High-risk Prostate Cancer: A Survey of North American Genitourinary Expert Radiation Oncologists.

PubMed

McClelland, Shearwood; Sandler, Kiri A; Degnin, Catherine; Chen, Yiyi; Mitin, Timur

2018-06-01

Three randomized clinical trials have established brachytherapy (BT) boost in combination with external beam radiation therapy (EBRT) and androgen deprivation therapy (ADT) as superior to definitive EBRT and ADT alone in terms of biochemical control (but not overall survival) at the expense of increased toxicity in men with high-risk (HR) prostate cancer (PCa). The current view regarding these 2 treatment algorithms among North American genitourinary (GU) experts is not known. A survey was distributed to 88 practicing North American GU physicians serving on decision-making committees of cooperative group research organizations. Questions pertained to opinions regarding BT as monotherapy for low-risk PCa and BT boost for HR PCa. Responders were asked to self-identify as BT experts versus non-experts. Treatment recommendations were correlated with practice patterns using the Fisher exact test. Forty-two radiation oncologists completed the survey, of whom 23 (55%) recommend EBRT and ADT alone and 19 (45%) recommend addition of BT boost. Twenty-five participants (60%) identified themselves as BT experts. Nearly 90% of those recommending BT boost were BT experts versus approximately 10% of non-BT experts (P < .001). Responders who recommended BT monotherapy as first-choice treatment for low-risk PCa were more likely to recommend BT boost for HR PCa (P < .0001). There is a dramatic polarization in opinions regarding incorporation of BT boost into EBRT + ADT therapy for patients with HR PCa among North American GU radiation oncology experts, who serve on decision-making committees and influence the national treatment guidelines and future clinical trials. Those who identify themselves as BT experts are significantly more likely to recommend BT boost. These findings are likely to influence the national guidelines and implementation of BT boost in current and future North American PCa clinical studies. Copyright © 2018 Elsevier Inc. All rights reserved.

Male sexual behavior contributes to the maintenance of high LH pulsatility in anestrous female goats.

PubMed

Vielma, Jesús; Chemineau, Philippe; Poindron, Pascal; Malpaux, Benoît; Delgadillo, José Alberto

2009-10-01

The objective of this study was to determine the importance of male sexual behavior in stimulating LH secretion in anovulatory female goats. Two groups of females (n=10 per group) were each exposed to a buck in sexual rest and submitted to natural daylength. In one group, the buck was awake, whereas in the other group, it was sedated to prevent its sexual behavior. Two other groups of goats (n=10 per group) were exposed to sexually active bucks that had been exposed to 2.5 months of long days. In one group, the buck was awake, and in the other group, it was sedated. LH secretion was determined every 15 min from 4 h before introducing the bucks to 8 h after, then every 15 min again from 20 to 24 h after introducing the bucks. The bucks submitted to natural daylength did not stimulate LH secretion (P>0.05), whether they were sedated or not. In contrast, both the awake and the sedated light-treated bucks induced an increase (P<0.05) of LH pulsatility in the first 4 h following their introduction. However, pulsatility remained elevated until 24 h in the females exposed to the light-treated awake buck, whereas in the group with the light-treated sedated buck, pulsatility diminished (P<0.05) after the first 4 h of stimulation by the buck. In conclusion, the sexual behavior of males contributes to the maintenance of a high LH pulsatility up to 24 h after introduction into a group of anovulatory goats.

A PWM Buck Converter With Load-Adaptive Power Transistor Scaling Scheme Using Analog-Digital Hybrid Control for High Energy Efficiency in Implantable Biomedical Systems.

PubMed

Park, Sung-Yun; Cho, Jihyun; Lee, Kyuseok; Yoon, Euisik

2015-12-01

We report a pulse width modulation (PWM) buck converter that is able to achieve a power conversion efficiency (PCE) of > 80% in light loads 100 μA) for implantable biomedical systems. In order to achieve a high PCE for the given light loads, the buck converter adaptively reconfigures the size of power PMOS and NMOS transistors and their gate drivers in accordance with load currents, while operating at a fixed frequency of 1 MHz. The buck converter employs the analog-digital hybrid control scheme for coarse/fine adjustment of power transistors. The coarse digital control generates an approximate duty cycle necessary for driving a given load and selects an appropriate width of power transistors to minimize redundant power dissipation. The fine analog control provides the final tuning of the duty cycle to compensate for the error from the coarse digital control. The mode switching between the analog and digital controls is accomplished by a mode arbiter which estimates the average of duty cycles for the given load condition from limit cycle oscillations (LCO) induced by coarse adjustment. The fabricated buck converter achieved a peak efficiency of 86.3% at 1.4 mA and > 80% efficiency for a wide range of load conditions from 45 μA to 4.1 mA, while generating 1 V output from 2.5-3.3 V supply. The converter occupies 0.375 mm(2) in 0.18 μm CMOS processes and requires two external components: 1.2 μF capacitor and 6.8 μH inductor.

Effect of low-speed impact damage on the buckling properties of E-glass/epoxy laminates

NASA Astrophysics Data System (ADS)

Yapici, A.; Metin, M.

2009-11-01

The postimpact buck ling loads of E-glass/epoxy laminates have been measured. Composite samples with the stacking sequence [+45/-45/90/0]2s were subjected to low-speed impact loadings at various energy levels. The tests were conducted on a specially developed vertical drop-weight testing machine. The main impact parameters, such as the peak load, absorbed energy, deflection at the peak load, and damage area, were evaluated and com pared. The damaged specimens were subjected to compressive axial forces, and their buckling loads were determined. The relation between the level of impact energy and buck ling loads is investigated.

Do wolves affect white-tailed buck harvest in northeastern Minnesota?

USGS Publications Warehouse

Mech, L. David; Nelson, Michael E.

2000-01-01

We used simple linear regression to analyze 8-23 years of data on a wolf (Canis lupus) population and human harvest of white-tailed deer (Odocoileus virginianus) bucks in northeastern Minnesota to determine any effects of wolves on buck harvesting. Over the long term, wolves accounted for at least 14-22% of the inter-year variation in buck harvest in the region, but an unknown amount of variation in hunter effort may have obscured any more precise estimate. For part of the area with poorest habitat, we found strong inverse relationships (r2 = 0.66-0.84) between annual wolf numbers and buck harvests from 1988 to 1995 when hunting pressure was considered relatively constant. However, in better habitat, where our buck harvest sample was larger, we found no evidence of wolves influencing buck harvest. Our findings tend to confirm the suitability of the Minnesota Department of Natural Resource's deer harvest regulations for a sustainable yield.

Gertrude Buck on Metaphor: Twentieth-Century Concepts in a Late Nineteenth-Century Dissertation.

ERIC Educational Resources Information Center

Vivian, Barbara G.

Gertrude Buck's doctoral dissertation, published in 1899, represented a radical departure from traditional treatments of metaphor. By approaching metaphor from an entirely new vantage point--psychology--Buck offered fresh insight and provided new explanations for the origin and function of figurative language. Buck made at least four other…

NREL Joins Initiative to Boost Power Electronics Energy Efficiency and Job

Science.gov Websites

Electronics and Electric Machines team, which focuses on vehicle component research and development (R&D current silicon-based components in the next five years. The institute will bring partners together to power electronics thermal management and reliability R&D, NREL's research in this area focuses on

Bidirectional DC/DC Converter

NASA Astrophysics Data System (ADS)

Pedersen, F.

2008-09-01

The presented bidirectional DC/DC converter design concept is a further development of an already existing converter used for low battery voltage operation.For low battery voltage operation a high efficient low parts count DC/DC converter was developed, and used in a satellite for the battery charge and battery discharge function.The converter consists in a bidirectional, non regulating DC/DC converter connected to a discharge regulating Buck converter and a charge regulating Buck converter.The Bidirectional non regulating DC/DC converter performs with relatively high efficiency even at relatively high currents, which here means up to 35Amps.This performance was obtained through the use of power MOSFET's with on- resistances of only a few mille Ohms connected to a special transformer allowing paralleling several transistor stages on the low voltage side of the transformer. The design is patent protected. Synchronous rectification leads to high efficiency at the low battery voltages considered, which was in the range 2,7- 4,3 Volt DC.The converter performs with low switching losses as zero voltage zero current switching is implemented in all switching positions of the converter.Now, the drive power needed, to switch a relatively large number of low Ohm , hence high drive capacitance, power MOSFET's using conventional drive techniques would limit the overall conversion efficiency.Therefore a resonant drive consuming considerable less power than a conventional drive circuit was implemented in the converter.To the originally built and patent protected bidirectional non regulating DC/DC converter, is added the functionality of regulation.Hereby the need for additional converter stages in form of a Charge Buck regulator and a Discharge Buck regulator is eliminated.The bidirectional DC/DC converter can be used in connection with batteries, motors, etc, where the bidirectional feature, simple design and high performance may be useful.

Induction logging device with a pair of mutually perpendicular bucking coils

DOEpatents

Koelle, Alfred R.; Landt, Jeremy A.

1981-01-01

An instrument is disclosed for mapping vertical conductive fractures in a resistive bedrock, magnetically inducing eddy currents by a pair of vertically oriented, mutually perpendicular, coplanar coils. The eddy currents drive magnetic fields which are picked up by a second, similar pair of coils.

Testicular biochemicals, sperm reserves and daily sperm production of West African dwarf bucks fed varied levels of dietary aflatoxin.

PubMed

Ewuola, E O; Jimoh, O A; Bello, A D; Bolarinwa, A O

2014-08-01

An experiment was conducted with twenty West African dwarf (WAD) bucks (5-6 months old) to assess reproductive potentials of growing WAD bucks to varied dietary aflatoxin of 0 μg/kg, 50 μg/kg, 100 μg/kg and 150 μg/kg containing in diets 1 (control) 2, 3 and 4 respectively, for a period of 12 weeks. At the end of the 12th week, the reproductive tracts of bucks were excised and homogenised in physiological saline for assessment of glucose, total protein and testosterone concentration, gonadal and extra gonadal sperm reserves. Results showed that gonadal and extra-gonadal sperm reserves of goats fed control diet (2.71×10(9) and 3.07×10(9) spermatozoa respectively) were superior (p<0.05) to those fed 50 μg/kg, 100 μg/kg and 15 0μg/kg [(1.59×10(9) and 2.33×10(9)), (1.09×10(9) and 2.45×10(9)) and (1.00×10(9) and 1.41×10(9)) spermatozoa respectively]. Daily sperm production of bucks fed the control diet was significantly (p<0.05) higher (7.60×10(8) spermatozoa/testis) than those fed 50 μg/kg (4.47×10(8)), 100 μg/kg (3.07×10(8)) and 150 μg/kg (2.80×10(8) spermatozoa/testis). Sperm production efficiency also follows the same trend as daily sperm production. Glucose and total protein concentration in the testes declined significantly as the aflatoxin level increases in the diets. Testosterone level was significantly lower in goats fed 100 μg/kg than others. The study suggest that exposure of male goats to dietary aflatoxin up to 50 μg/kg diet will reduced testicular biochemical and testosterone with resultant depression in sperm storage capability and daily sperm production in the animals. Copyright © 2014 Elsevier B.V. All rights reserved.

HW Buck for Windows: the optimal hardwood log bucking decision simulator with expanded capabilities

Treesearch

James B. Pickens; Scott Noble; Blair Orr; Philip A. Araman; John E. Baumgras; Al Steele

2006-01-01

It has long been recognized that inappropriate placement of crosscuts when manufacturing hardwood logs from harvested stems (log bucking) reduces the value of logs produced. Recent studies have estimated losses in the range from 28% to 38% in the lake states region. These estimates were developed by evaluating the bucking cuts chosen by harvesting crews and comparing...

A PIPO Boost Converter with Low Ripple and Medium Current Application

NASA Astrophysics Data System (ADS)

Bandri, S.; Sofian, A.; Ismail, F.

2018-04-01

This paper presents a Parallel Input Parallel Output (PIPO) boost converter is proposed to gain power ability of converter, and reduce current inductors. The proposed technique will distribute current for n-parallel inductor and switching component. Four parallel boost converters implement on input voltage 20.5Vdc to generate output voltage 28.8Vdc. The PIPO boost converter applied phase shift pulse width modulation which will compare with conventional PIPO boost converters by using a similar pulse for every switching component. The current ripple reduction shows an advantage PIPO boost converter then conventional boost converter. Varies loads and duty cycle will be simulated and analyzed to verify the performance of PIPO boost converter. Finally, the unbalance of current inductor is able to be verified on four area of duty cycle in less than 0.6.

Dispersal and population state of an endangered island lizard following a conservation translocation.

PubMed

Angeli, Nicole F; Lundgren, Ian F; Pollock, Clayton G; Hillis-Starr, Zandy M; Fitzgerald, Lee A

2018-03-01

Population size is widely used as a unit of ecological analysis, yet to estimate population size requires accounting for observed and latent heterogeneity influencing dispersion of individuals across landscapes. In newly established populations, such as when animals are translocated for conservation, dispersal and availability of resources influence patterns of abundance. We developed a process to estimate population size using N-mixture models and spatial models for newly established and dispersing populations. We used our approach to estimate the population size of critically endangered St. Croix ground lizards (Ameiva polops) five years after translocation of 57 individuals to Buck Island, an offshore island of St. Croix, United States Virgin Islands. Estimates of population size incorporated abiotic variables, dispersal limits, and operative environmental temperature available to the lizards to account for low species detection. Operative environmental temperature and distance from the translocation site were always important in fitting the N-mixture model indicating effects of dispersal and species biology on estimates of population size. We found that the population is increasing its range across the island by 5-10% every six months. We spatially interpolated site-specific abundance from the N-mixture model to the entire island, and we estimated 1,473 (95% CI, 940-1,802) St. Croix ground lizards on Buck Island in 2013 corresponding to survey results. This represents a 26-fold increase since the translocation. We predicted the future dispersal of the lizards to all habitats on Buck Island, with the potential for the population to increase by another five times in the future. Incorporating biologically relevant covariates as explicit parameters in population models can improve predictions of population size and the future spread of species introduced to new localities. © 2018 by the Ecological Society of America.

Evaluation of rumen-protected choline additive to diet on productive performance of male Zaraibi growing goats during hot summer season in Egypt.

PubMed

Habeeb, A A M; Gad, A E; Atta, M A A; Abdel-Hafez, M A M

2017-08-01

Twenty Zaraibi goat bucks were used in this experiment which lasted 3 months during summer season of Egypt. The animals were divided randomly into two equal groups. The first group was kept without treatment as control while in the second group, rumen-protected choline (RPC) at the level of 20 g/buck/day was added to the concentrate feed mixture at the morning feeding. RPC additives to diet of Zaraibi goat bucks during the period of hot summer season increased (P < 0.01) total gain and average daily gain compared to the control group. RPC increased (P < 0.05) dry matter intake and feed conversion while water intake was not affected by RPC additives. RPC increased (P < 0.05) red and white blood cell (RBC × 10 6 , WBC × 10 3 ) counts and hemoglobin concentration and hematocrit percentage. RPC increased total protein (P < 0.05), globulin, and γ-globulin (P < 0.01). On the other hand, total lipids, total cholesterol, and triglyceride concentrations decreased (P < 0.05 and P < 0.05) while phospholipids, glucose, and choline concentrations increased (P < 0.01) due to RPC supplementation. RPC increased (P < 0.01) thyroxin and triiodothyronine, increased (P < 0.05) testosterone levels, and decreased (P < 0.01) cortisol level compared with control bucks. It is concluded that dietary RPC at the rate of 20 g daily is required for growing male goats, especially, under heat stress conditions of summer season in Egypt and showed the best results concerning the growth, feed conversion, blood metabolites, and economic efficiency.

Effect of body condition score of does and use of bucks subjected to added artificial light on estrus response of Alpine goats.

PubMed

Rivas-Muñoz, Raymundo; Carrillo, Evaristo; Rodriguez-Martinez, Rafael; Leyva, Carlos; Mellado, Miguel; Véliz, Francisco Gerardo

2010-08-01

The effects of body condition score of does and exposure to sexually active bucks after exposure to long-day artificial photoperiod were examined in mature anovulatory French Alpine goat in Northern Mexico. In June, goats in good (2.3 +/- 0.2, scale 1 to 4; n = 10) or poor (1.6 +/- 0.3; n = 10) body condition were exposed during 15 day to sexually active bucks, which had been exposed to long photoperiod (16:8-h light-dark cycle, starting in December). A third group of goats in good body condition was exposed to bucks kept under the natural photoperiod of this region (26 degrees N). All goats in good body condition exposed to bucks treated with prolonged photoperiod exhibited estrus behavior, whereas only 50% of the does in poor body condition showed estrous behavior during the 15-day buck exposure. None of the does in good body condition showed estrus when exposed to bucks under natural photoperiod. These results revealed that a good body condition is required for maximum estrus response in anestrous Alpine goats and that exposure of bucks to long photoperiod in winter is essential for an adequate stimulus to reestablish estrus cycles in anovulatory Alpine does in Northern Mexico.

Testicular lesions and antler abnormalities in Colorado, USA mule deer (Odocoileus hemionus): a possible role for epizootic hemorrhagic disease virus.

PubMed

Fox, Karen A; Diamond, Brandon; Sun, Feng; Clavijo, Alfonso; Sneed, Loyd; Kitchen, Donald N; Wolfe, Lisa L

2015-01-01

Antler abnormalities of deer and other cervids often result from testicular lesions and decreased levels of testosterone, inhibiting normal cycles of antler growth. Affected males have antlers with retained velvet, numerous short, misshapen points ("cactus bucks"), and failure to shed these abnormal antlers annually. In Colorado, US, we observed a high occurrence of "cactus bucks" in mule deer (Odocoileus hemionus) populations after management efforts to increase the number of mature male deer in the state. Affected males consistently had antibody to epizootic hemorrhagic disease virus serotype 2 (EHDV-2), and examination of the testes of these animals demonstrated nonspecific end-stage lesions of chronic inflammation, fibrosis, and mineralization. To examine more acute stages of testicular lesions, and to screen for EHDV specifically within the testes, we sampled 16 male mule deer from affected herds, but with essentially normal antlers (n = 14) or retained velvet only (n = 2). Testicular and epididymal lesions identified from these samples included necrotizing vasculitis (n = 2), hemorrhage (n = 6), edema (n = 2), seminiferous tubular necrosis (n = 5), orchitis (n = 5), epididymitis (n = 10), hypospermia (n = 6), and end-stage lesions of seminiferous tubular loss (n = 2), fibrosis (n = 2), and mineralization (n = 2). Each of the 16 cases was blindly scored on the basis of number of histologic lesions, with a median score of two. Five of seven (71%) testes that were PCR positive for EHDV had lesion scores above the median, whereas none of the nine (0%) EHDV PCR-negative testes had lesion scores above the median, suggesting an association between testicular lesions and detection of EHDV RNA in the testes (P = 0.003). Although the role of EHDV infection remains unconfirmed, the association between testicular and epididymal lesions and presence of EHDV RNA in the affected tissues suggests that cactus buck antlers may be a sequela of EHDV infection.

Toxic effects of arsenic on semen and hormonal profile and their amelioration with vitamin E in Teddy goat bucks.

PubMed

Zubair, M; Ahmad, M; Jamil, H; Deeba, F

2016-12-01

The present environmental study has been planned to investigate the toxic effects of arsenic on reproductive functions of Teddy bucks as well as to examine whether these toxic effects are ameliorated by vitamin E. Sixteen adult Teddy bucks were divided randomly into four equal groups A, B, C and D with following treatment: A (control), B (sodium arsenite 5 mg kg -1 BW day -1 ), C (vit E 200 mg kg -1 BW day -1  + Arsenic 5 mg kg -1 BW day -1 ) and D (vit E 200 mg kg -1 BW day -1 ). This treatment was continued for 84 days. Semen quality parameters were evaluated weekly. Male testosterone, luteinising hormone (LH), follicle-stimulating hormone (FSH) and cortisol levels were measured through enzyme-linked immunosorbent assay (ELISA) after every 2 weeks. The data were subjected to two-way analysis of variance followed by Duncan test for multiple comparisons. Semen evaluation parameters were reduced significantly (P < 0.05) in arsenic-treated animals. The serum hormonal profile of testosterone, LH and FSH was reduced significantly (P < 0.05) in arsenic group, while the serum level of cortisol was increased. Vitamin E alleviated the toxic effects of arsenic on semen and hormonal parameters. It may be concluded from this study that sodium arsenite causes major toxicity changes in semen and hormonal profile in Teddy goat bucks and vitamin E has ameliorative effects on these toxic changes. © 2016 Blackwell Verlag GmbH.

A matter of scale: damage from Hurricane Hugo (1989) to U.S. Virgin Islands reefs at the colony, community and whole reef level

USGS Publications Warehouse

Rogers, Caroline S.

1993-01-01

Studies at Buck Island Reef National Monument (St. Croix) and Virgin Islands National Park (St. John) by scientists in the U.S. National Park Service Coral Reef Assessment Program re- vealed the effects of Humcane Hugo on individual coral species, community parameters, and overall reef structure. Effects of the storm varied with depth, coral species, location relative to the storm path, character of the pre-storm communities, and ecological history. Live coral cover, initially less than 30% at all sites, dropped by 40 to 73%. Cover by the dominant species Montastrea annularis de- clined about 35% on the St. John reefs. At Buck Island, Acropora palmata cover, already reduced from 85% to 5% by white band disease and storms, fell to 0.8% after Hugo. Some areas on the south side of Buck Island were reduced to rubble pave- ment while other areas escaped serious damage. Data from cores at Buck Island reveal the influence of wave energy and storm frequency on overall reef character. Patchiness and variation in the responses of different species, zones, and entire reefs to the storm suggest that assessment of long-term trends in reef structure and composition requires analysis of changes at permanent study sites distributed over large areas.

Design of a Miniaturized RAD Hard Point-of-Load Converter

NASA Astrophysics Data System (ADS)

Lofgren, Henrik; Landstrom, Sven; Gunnarsson, Marcus; Hagstrom, Maria

2014-08-01

As an ARTES 5.2 activity, a miniaturized radiation hardened Point-Of-Load converter (uPOL) has been developed. Several different design options have been evaluated before the final system level design was selected. The selected topology is a buck regulator with synchronous rectification utilizing peak current mode control. The PWM logic is designed using discrete electronics. Inside the POL converter package, an independent latching current limiter and clamping over- voltage protection are included as protection devices. The converter has an input voltage range of 4.8-6.2V, output voltage range of 1.2-3.5V and an output current of 0-3.5A. The final converter will be a metal packaged hybrid built on LTCC technology with an operating case temperature range of -40 to +85 °C.

96. CENTRAL COURT. MERCER MUSEUM, FROM ENTRY LEVEL SAME VIEW ...

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

96. CENTRAL COURT. MERCER MUSEUM, FROM ENTRY LEVEL SAME VIEW AS PA-107-67. - Moravian Pottery & Tile Works, Southwest side of State Route 313 (Swamp Road), Northwest of East Court Street, Doylestown, Bucks County, PA

20. Photocopy of photograph (from the Bucks County Historical Society) ...

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

20. Photocopy of photograph (from the Bucks County Historical Society) photographer and date unknown GENERAL VIEW FROM THE SOUTHWEST - Moravian Pottery & Tile Works, Southwest side of State Route 313 (Swamp Road), Northwest of East Court Street, Doylestown, Bucks County, PA

Humoral and B-cell memory responses in children five years after pertussis acellular vaccine priming.

PubMed

Carollo, Maria; Pandolfi, Elisabetta; Tozzi, Alberto Eugenio; Buisman, Anne-Marie; Mascart, Françoise; Ausiello, Clara Maria

2014-04-11

The resurgence of pertussis suggests the need for greater efforts in understanding the long-lasting protective responses induced by vaccination. In this paper we dissect the persistence of humoral and B-cell memory responses induced by primary vaccination with two different acellular pertussis (aP) vaccines, hexavalent Hexavac(®) vaccine (Hexavac) (Sanofi Pasteur MSD) and Infanrix hexa(®) (Infanrix) (GlaxoSmithKline Biologicals). We evaluated the specific immune responses in the two groups of children, 5 years after primary vaccination by measuring the persistence of IgG and antibody secreting cells (ASC) specific for vaccine antigens. Part of the enrolled children received only primary vaccination, while others had the pre-school boost dose. A similar level of antigen-specific IgG and ASC was found in Infanrix and Hexavac vaccinated children. The mean IgG levels were significantly higher in children that received the pre-school boost as compared with children that did not receive the boost dose. A longer persistence after the pre-school boost of IgG-Pertussis Toxin (PT) and IgG-pertactin levels was observed in Infanrix primed children, but it was not statistically significant. More than 80% of children presented a positive ASC B memory response. Around 50% of children still presented protective IgG-PT levels which are reduced to 36% in no-boosted children. The pre-school booster dose restores the percentage of protected children above 50%. In conclusion our data underline the importance of giving a booster dose 5 years after primary vaccination and suggest the need for a new vaccine able to induce a long lasting protective response. Copyright © 2014 Elsevier Ltd. All rights reserved.

The Impact of New York City’s Health Bucks Program on Electronic Benefit Transfer Spending at Farmers Markets, 2006–2009

PubMed Central

Dunn, Lillian; Nonas, Cathy; Dannefer, Rachel; Sacks, Rachel

2013-01-01

Introduction Increasing the accessibility and affordability of fresh produce is an important strategy for municipalities combatting obesity and related health conditions. Farmers markets offer a promising venue for intervention in urban settings, and in recent years, an increasing number of programs have provided financial incentives to Supplemental Nutrition Assistance Program (SNAP) recipients. However, few studies have explored the impact of these programs on use of SNAP benefits at farmers markets. Methods New York City’s Health Bucks Program provides SNAP recipients with a $2 coupon for every $5 spent using SNAP benefits at participating farmers markets. We analyzed approximately 4 years of electronic benefit transfer (EBT) sales data, from July 2006 through November 2009, to develop a preliminary assessment of the effect of the Health Bucks Program on EBT spending at participating markets. Results Farmers markets that offered Health Bucks coupons to SNAP recipients averaged higher daily EBT sales than markets without the incentive ($383.07, 95% confidence interval [CI], 333.1–433.1, vs $273.97, 95% CI, 243.4–304.5, P < 0.001) following the introduction of a direct point-of-purchase incentive. Multivariate analysis indicated this difference remained after adjusting for the year the market was held and the neighborhood poverty level. Conclusion When a $2 financial incentive was distributed with EBT, use of SNAP benefits increased at participating New York City farmers markets. We encourage other urban jurisdictions to consider adapting the Health Bucks Program to encourage low-income shoppers to purchase fresh produce as one potential strategy in a comprehensive approach to increasing healthful food access and affordability in low-income neighborhoods. PMID:24070035

The impact of New York City's Health Bucks Program on electronic benefit transfer spending at farmers markets, 2006-2009.

PubMed

Baronberg, Sabrina; Dunn, Lillian; Nonas, Cathy; Dannefer, Rachel; Sacks, Rachel

2013-09-26

Increasing the accessibility and affordability of fresh produce is an important strategy for municipalities combatting obesity and related health conditions. Farmers markets offer a promising venue for intervention in urban settings, and in recent years, an increasing number of programs have provided financial incentives to Supplemental Nutrition Assistance Program (SNAP) recipients. However, few studies have explored the impact of these programs on use of SNAP benefits at farmers markets. New York City's Health Bucks Program provides SNAP recipients with a $2 coupon for every $5 spent using SNAP benefits at participating farmers markets. We analyzed approximately 4 years of electronic benefit transfer (EBT) sales data, from July 2006 through November 2009, to develop a preliminary assessment of the effect of the Health Bucks Program on EBT spending at participating markets. Farmers markets that offered Health Bucks coupons to SNAP recipients averaged higher daily EBT sales than markets without the incentive ($383.07, 95% confidence interval [CI], 333.1-433.1, vs $273.97, 95% CI, 243.4-304.5, P < 0.001) following the introduction of a direct point-of-purchase incentive. Multivariate analysis indicated this difference remained after adjusting for the year the market was held and the neighborhood poverty level. When a $2 financial incentive was distributed with EBT, use of SNAP benefits increased at participating New York City farmers markets. We encourage other urban jurisdictions to consider adapting the Health Bucks Program to encourage low-income shoppers to purchase fresh produce as one potential strategy in a comprehensive approach to increasing healthful food access and affordability in low-income neighborhoods.

Modeling and control of fuel cell based distributed generation systems

NASA Astrophysics Data System (ADS)

Jung, Jin Woo

This dissertation presents circuit models and control algorithms of fuel cell based distributed generation systems (DGS) for two DGS topologies. In the first topology, each DGS unit utilizes a battery in parallel to the fuel cell in a standalone AC power plant and a grid-interconnection. In the second topology, a Z-source converter, which employs both the L and C passive components and shoot-through zero vectors instead of the conventional DC/DC boost power converter in order to step up the DC-link voltage, is adopted for a standalone AC power supply. In Topology 1, two applications are studied: a standalone power generation (Single DGS Unit and Two DGS Units) and a grid-interconnection. First, dynamic model of the fuel cell is given based on electrochemical process. Second, two full-bridge DC to DC converters are adopted and their controllers are designed: an unidirectional full-bridge DC to DC boost converter for the fuel cell and a bidirectional full-bridge DC to DC buck/boost converter for the battery. Third, for a three-phase DC to AC inverter without or with a Delta/Y transformer, a discrete-time state space circuit model is given and two discrete-time feedback controllers are designed: voltage controller in the outer loop and current controller in the inner loop. And last, for load sharing of two DGS units and power flow control of two DGS units or the DGS connected to the grid, real and reactive power controllers are proposed. Particularly, for the grid-connected DGS application, a synchronization issue between an islanding mode and a paralleling mode to the grid is investigated, and two case studies are performed. To demonstrate the proposed circuit models and control strategies, simulation test-beds using Matlab/Simulink are constructed for each configuration of the fuel cell based DGS with a three-phase AC 120 V (L-N)/60 Hz/50 kVA and various simulation results are presented. In Topology 2, this dissertation presents system modeling, modified space vector PWM implementation (MSVPWM) and design of a closed-loop controller of the Z-source converter which utilizes L and C components and shoot-through zero vectors for the standalone AC power generation. The fuel cell system is modeled by an electrical R-C circuit in order to include slow dynamics of the fuel cells and a voltage-current characteristic of a cell is also considered. A discrete-time state space model is derived to implement digital control and a space vector pulse-width modulation (SVPWM) technique is modified to realize the shoot-through zero vectors that boost the DC-link voltage. Also, three discrete-time feedback controllers are designed: a discrete-time optimal voltage controller, a discrete-time sliding mode current controller, and a discrete-time PI DC-link voltage controller. Furthermore, an asymptotic observer is used to reduce the number of sensors and enhance the reliability of the system. To demonstrate the analyzed circuit model and proposed control strategy, various simulation results using Matlab/Simulink are presented under both light/heavy loads and linear/nonlinear loads for a three-phase AC 208 V (L-L)/60 Hz/10 kVA.

76 FR 2878 - Six Rivers National Forest, Mad River Ranger District, CA; Buck Mountain Vegetation and Fuel...

Federal Register 2010, 2011, 2012, 2013, 2014

2011-01-18

...; Buck Mountain Vegetation and Fuel Management Project EIS AGENCY: Forest Service, USDA. ACTION: Notice... the Buck Mountain Vegetation and Fuel Management Project to accelerate late-successional forest... project design features have been identified. Late-Successional Reserve Management Silvicultural...

36 CFR 7.73 - Buck Island Reef National Monument.

Code of Federal Regulations, 2013 CFR

2013-07-01

...), seashells, corals, dead coral, sea fans, sponges and all associated reef invertebrates, plants, fruits and... 36 Parks, Forests, and Public Property 1 2013-07-01 2013-07-01 false Buck Island Reef National... INTERIOR SPECIAL REGULATIONS, AREAS OF THE NATIONAL PARK SYSTEM § 7.73 Buck Island Reef National Monument...

36 CFR 7.73 - Buck Island Reef National Monument.

Code of Federal Regulations, 2012 CFR

2012-07-01

...), seashells, corals, dead coral, sea fans, sponges and all associated reef invertebrates, plants, fruits and... 36 Parks, Forests, and Public Property 1 2012-07-01 2012-07-01 false Buck Island Reef National... INTERIOR SPECIAL REGULATIONS, AREAS OF THE NATIONAL PARK SYSTEM § 7.73 Buck Island Reef National Monument...

36 CFR 7.73 - Buck Island Reef National Monument.

Code of Federal Regulations, 2014 CFR

2014-07-01

...), seashells, corals, dead coral, sea fans, sponges and all associated reef invertebrates, plants, fruits and... 36 Parks, Forests, and Public Property 1 2014-07-01 2014-07-01 false Buck Island Reef National... INTERIOR SPECIAL REGULATIONS, AREAS OF THE NATIONAL PARK SYSTEM § 7.73 Buck Island Reef National Monument...

36 CFR 7.73 - Buck Island Reef National Monument.

Code of Federal Regulations, 2010 CFR

2010-07-01

...), seashells, corals, dead coral, sea fans, sponges and all associated reef invertebrates, plants, fruits and... 36 Parks, Forests, and Public Property 1 2010-07-01 2010-07-01 false Buck Island Reef National... INTERIOR SPECIAL REGULATIONS, AREAS OF THE NATIONAL PARK SYSTEM § 7.73 Buck Island Reef National Monument...

36 CFR 7.73 - Buck Island Reef National Monument.

Code of Federal Regulations, 2011 CFR

2011-07-01

...), seashells, corals, dead coral, sea fans, sponges and all associated reef invertebrates, plants, fruits and... 36 Parks, Forests, and Public Property 1 2011-07-01 2011-07-01 false Buck Island Reef National... INTERIOR SPECIAL REGULATIONS, AREAS OF THE NATIONAL PARK SYSTEM § 7.73 Buck Island Reef National Monument...

9. INTERIOR VIEW, FIRST FLOOR, NORTHEAST ROOM, EAST WALL, ORIGINAL ...

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

9. INTERIOR VIEW, FIRST FLOOR, NORTHEAST ROOM, EAST WALL, ORIGINAL KITCHEN FIREPLACE AND BAKE OVEN, WITH OPEN DOORWAY INTO CURRENT KITCHEN - Edgemont, 212 Bridgetown Pike, 1/4 mile East of PA 413 (Middletown Township), Langhorne, Bucks County, PA

Boosting Social and Emotional Competence

ERIC Educational Resources Information Center

Beland, Kathy

2007-01-01

Beland maintains that high school students will need a high level of skill in the social and emotional arena to be ready for competitive employment in the 21st century. In a 2006 survey, human resource professionals said five skills were most crucial to high school graduates' success: professionalism/work ethic; teamwork; oral communications;…

Design of transient light signal simulator based on FPGA

NASA Astrophysics Data System (ADS)

Kang, Jing; Chen, Rong-li; Wang, Hong

2014-11-01

A design scheme of transient light signal simulator based on Field Programmable gate Array (FPGA) was proposed in this paper. Based on the characteristics of transient light signals and measured feature points of optical intensity signals, a fitted curve was created in MATLAB. And then the wave data was stored in a programmed memory chip AT29C1024 by using SUPERPRO programmer. The control logic was realized inside one EP3C16 FPGA chip. Data readout, data stream cache and a constant current buck regulator for powering high-brightness LEDs were all controlled by FPGA. A 12-Bit multiplying CMOS digital-to-analog converter (DAC) DAC7545 and an amplifier OPA277 were used to convert digital signals to voltage signals. A voltage-controlled current source constituted by a NPN transistor and an operational amplifier controlled LED array diming to achieve simulation of transient light signal. LM3405A, 1A Constant Current Buck Regulator for Powering LEDs, was used to simulate strong background signal in space. Experimental results showed that the scheme as a transient light signal simulator can satisfy the requests of the design stably.

An optimal design of magnetostrictive material (MsM) based energy harvester

NASA Astrophysics Data System (ADS)

Hu, Jingzhen; Yuan, Fuh-Gwo; Xu, Fujun; Huang, Alex Q.

2010-04-01

In this study, an optimal vibration-based energy harvesting system using magnetostrictive material (MsM) has been designed to power the Wireless Intelligent Sensor Platform (WISP), developed at North Carolina State University. A linear MsM energy harvesting device has been modeled and optimized to maximize the power output. The effects of number of MsM layers and glue layers, and load matching on the output power of the MsM energy harvester have been analyzed. From the measurement, the open circuit voltage can reach 1.5 V when the MsM cantilever beam operates at the 2nd natural frequency 324 Hz. The AC output power is 0.97 mW, giving power density 279 μW/cm3. Since the MsM device has low open circuit output voltage characteristics, a full-wave quadrupler has been designed to boost the rectified output voltage. To deliver the maximum output power to the load, a complex conjugate impedance matching between the load and the MsM device has been implemented using a discontinuous conduction mode (DCM) buck-boost converter. The maximum output power after the voltage quadrupler is now 705 μW and power density reduces to 202.4 μW/cm3, which is comparable to the piezoelectric energy harvesters given in the literature. The output power delivered to a lithium rechargeable battery is around 630 μW, independent of the load resistance.

Biological Determinism and the Concept of Mental Retardation: The Lesson of Carrie Buck.

ERIC Educational Resources Information Center

Smith, J. David

This paper reviews the case of Carrie Buck, who was the first person sterilized (in 1927) under a Virginia law allowing sterilization of persons identified as incompetent and likely to genetically transmit physical, psychological, or social deficiencies to their offspring. This law was later upheld by the Supreme Court in Buck v. Bell, which…

Geologic Controls of Sand Boil Formation at Buck Chute, Mississippi

DTIC Science & Technology

2017-06-30

12 Figure 6. 1915 MRC hydrographic survey of Buck Chute (Modified from MRC 1975, sheet 48). ............ 13 Figure 7. 1926 MRC...hydrographic survey of Buck Chute (Modified from MRC 1975, sheet 48). ............ 14 Figure 8. Diagram of the evolution of the Mississippi River...library). .................... 17 Figure 11. AGI SuperSting 8 ERT survey equipment

Value recovery from two mechanized bucking operations in the southeastern United States

Treesearch

Kevin Boston; Glen. Murphy

2003-01-01

The value recovered from two mechanized bucking operations in the southeastern United States was compared with the optimal value computed using an individual-stem log optimization program, AVIS. The first operation recovered 94% of the optimal value. The main cause for the value loss was a failure to capture potential sawlog volume; logs were bucked to a larger average...

Boosting Manufacturing through Modular Chemical Process Intensification

ScienceCinema

None

2018-06-12

Manufacturing USA's Rapid Advancement in Process Intensification Deployment Institute will focus on developing breakthrough technologies to boost domestic energy productivity and energy efficiency by 20 percent in five years through manufacturing processes.

Boosting Manufacturing through Modular Chemical Process Intensification

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

None

2016-12-09

Manufacturing USA's Rapid Advancement in Process Intensification Deployment Institute will focus on developing breakthrough technologies to boost domestic energy productivity and energy efficiency by 20 percent in five years through manufacturing processes.

Addressing Circuitous Currents MVDC Power Systems Protection

DTIC Science & Technology

2017-12-31

load . The converter modules are current-controlled buck converters. They are being controlled to provide a no - load voltage of 155V at their outputs...PAGE Form Approved 0MB No . 0704-0188 The public reporting burden for this collection of information is estimated to average 1 hour per response...distribution is unlimited 13. SUPPLEMENTARY NOTES 14. ABSTRACT The work investigates Z-source breakers in multi-zone systems with current to the load through

The Vilification and Vindication of Colonel Kuklinski

DTIC Science & Technology

2000-01-01

Brzezinski , �Kuklinski�s informa tion permitted us to make counterplans to disrupt com mand-and-control facilities rather than only relying on a massive...final verdict �~3 This buck-pass ing would continue for another five years. Dr. Brzezinski was Kuklinski�s earli est and ultimately his most...return to Poland, � Brzezinski was Kuklinski�s earliest and ultimately his most effective champion. 9~ despite his legal problems, to com memorate the

Bucking logs to cable yarder capacity can decrease yarding costs and minimize wood wastage

Treesearch

Chris B. LeDoux

1986-01-01

Data from select time and motions studies and a forest model plot, used in a simulation model, show that logging managers planning felling, bucking, and limbing for a cable yarding operation must consider the effect of alternate bucking rules on wood wastage, yarding production rates and cost, the number of choker to fly and total logging costs. Results emphasize then...

The interbreeding of sheep and goats.

PubMed Central

Kelk, D A; Gartley, C J; Buckrell, B C; King, W A

1997-01-01

To determine the outcome of interbreeding sheep and goats, ewes and does were bred to rams and bucks, and their embryos recovered. Pregnancy was monitored in 2 does bred to a ram. Fertilization rates in ram X does, buck X does, ram X ewes, and buck X ewes were 72%, 96%, 90%, and 0%, respectively. Ram X doe fetuses died at 5 to 10 weeks. PMID:9105723

10 CFR Appendix H to Part 73 - Weapons Qualification Criteria

Code of Federal Regulations, 2014 CFR

2014-01-01

... position Shotgun 1 1 7 yards 2 Double 0 buck-shot 4 seconds At low ready position fire 2 rounds standing Minimum qualifying = 70%. 2 12 15 yards 4 Double 0 buck-shot 15 seconds At low ready position fire 2 rounds standing, reload and fire 2 rounds 3 12 25 yards 4 rifled slugs or 00 buck-shot 20 seconds On...

10 CFR Appendix H to Part 73 - Weapons Qualification Criteria

Code of Federal Regulations, 2011 CFR

2011-01-01

... position Shotgun 1 1 7 yards 2 Double 0 buck-shot 4 seconds At low ready position fire 2 rounds standing Minimum qualifying = 70%. 2 12 15 yards 4 Double 0 buck-shot 15 seconds At low ready position fire 2 rounds standing, reload and fire 2 rounds 3 12 25 yards 4 rifled slugs or 00 buck-shot 20 seconds On...

10 CFR Appendix H to Part 73 - Weapons Qualification Criteria

Code of Federal Regulations, 2012 CFR

2012-01-01

... position Shotgun 1 1 7 yards 2 Double 0 buck-shot 4 seconds At low ready position fire 2 rounds standing Minimum qualifying = 70%. 2 12 15 yards 4 Double 0 buck-shot 15 seconds At low ready position fire 2 rounds standing, reload and fire 2 rounds 3 12 25 yards 4 rifled slugs or 00 buck-shot 20 seconds On...

10 CFR Appendix H to Part 73 - Weapons Qualification Criteria

Code of Federal Regulations, 2010 CFR

2010-01-01

... position Shotgun 1 1 7 yards 2 Double 0 buck-shot 4 seconds At low ready position fire 2 rounds standing Minimum qualifying = 70%. 2 12 15 yards 4 Double 0 buck-shot 15 seconds At low ready position fire 2 rounds standing, reload and fire 2 rounds 3 12 25 yards 4 rifled slugs or 00 buck-shot 20 seconds On...

10 CFR Appendix H to Part 73 - Weapons Qualification Criteria

Code of Federal Regulations, 2013 CFR

2013-01-01

... position Shotgun 1 1 7 yards 2 Double 0 buck-shot 4 seconds At low ready position fire 2 rounds standing Minimum qualifying = 70%. 2 12 15 yards 4 Double 0 buck-shot 15 seconds At low ready position fire 2 rounds standing, reload and fire 2 rounds 3 12 25 yards 4 rifled slugs or 00 buck-shot 20 seconds On...

Investigation of ethylene dibromide (EDB) in ground water in Seminole County, Georgia

USGS Publications Warehouse

McConnell, James B.; Hicks, D.W.; Lowe, L. E.; Cohen, S.Z.; Jovanovich, A.P.

1984-01-01

An investigation of ground water in Seminole County, Georgia, for ethylene dibromide (EDB) was conducted in August 1983 by the U.S. Geological Survey in cooperation with the Exposure Assessment Branch of the U.S. Environmental Protection Agency. The purpose of the investigation was to determine whether EDB, which was previously detected in ground-water samples from four neighboring wells, was localized in the vicinity of the wells or was more widespread in the ground-water system. EDB was detected in 6 of 19 wells sampled. Concentrations ranged from 0.03 to 11.8 micrograms per liter. Five of the six samples that contained EDB were collected from irrigation wells, and one was collected from a domestic well. Concentrations of 4.5 and 11.8 micrograms per liter were found in two irrigation wells located near Buck Hole, a sinkhole in a swampy depression in central Seminole County. EDB was not detected in samples from the remaining 10 irrigation and 3 domestic wells and the surface-water site (detection level less than 0.01 microgram per liter). Nine core samples were collected from a borehole near one of the irrigation wells that had high EDB concentrations. EDB was found in a core sample near the surface and in samples from depths of 24 to 25, 34 to 35, and 39 to 40 feet in the residuum. EDB concentrations in the core samples ranged from 0.06 to 2.4 micrograms per kilogram. EDB in the aquifer was found in a 4-square-mile area of the county in the vicinity of Buck Hole. EDB application information and the local hydrogeology indicate that EDB contamination in ground water in Seminole County probably is due to soil fumigation with EDB. Apparently, EDB moves downward through the residuum and, through undetermined pathways, enters the aquifer. However, because the high concentration of EDB in the aquifer seems to be localized in the Buck Hole area, the possibility of contamination from an EDB fumigant spill cannot be disregarded at this time.

Cannabis, alcohol use, psychological distress, and decision-making style.

PubMed

Phillips, James G; Ogeil, Rowan P

2017-09-01

There have been suggestions of hypofrontality in cannabis users. To understand cannabis-related differences in decisional processes, Janis and Mann's conflict model of decision making was applied to recreational cannabis smokers who varied in their alcohol use and level of psychological distress. An online sample of recreational substance users (114 male, 119 female) completed the Melbourne Decision Making Questionnaire, the Alcohol Use Disorders Identification Test (AUDIT), Kessler's Psychological Distress Scale (K10), and the Severity of Dependence Scale (SDS) for cannabis. Multivariate analysis of variance examined self-reported decision-making styles as a function of gender, recent cannabis use, risky alcohol consumption, and levels of psychological distress. Psychological distress was associated with lower decisional self-esteem and higher levels of procrastination and buck-passing. There were gender differences associated with cannabis use. Female cannabis users reported higher levels of hypervigilance, while male cannabis users reported lower levels of buck-passing. Although there was little indication of an avoidant decisional style in cannabis users, the results suggest that cannabis affects decisional processes, contributing to panic in females and impulsivity in males.

Analysis of Voltage and Current Signal Processing in a Li-ion Battery Management System

DTIC Science & Technology

2010-09-01

SUBJECT TERMS Pulsed Power, Charger, Buck Converter, Field Programmable Gate Array (FPGA), Lithium - ion Batteries 16. PRICE CODE 17. SECURITY...Congressional Research Service. July 31, 2000. [3] F. E. Filler, “A Pulsed Power System Design Using Lithium - ion Batteries and One Charger per Battery

Cryoprotective role of organic Zn and Cu supplementation in goats (Capra hircus) diet.

PubMed

Arangasamy, Arunachalam; Krishnaiah, Mayasula Venkata; Manohar, Narasimhaiah; Selvaraju, Sellappan; Rani, Guvvala Pushpa; Soren, Nira Manik; Reddy, Ippala Janardhan; Ravindra, Janivara Parameshwaraiah

2018-04-01

The current study focused on cryopreservation and assessment of characters of post-thaw semen of indigenous Osmanabadi bucks maintained with standard diet, supplemented with different concentrations of organic zinc (Zn), copper (Cu) or in combination, for a period of 180 days. The different doses of organic Zn and Cu were fed per kg DM basis, Zn groups (low: Zn20, medium: Zn40 and high: Zn60), Cu groups: (low: Cu12.5, medium: Cu25 and high: Cu37.5) and combination of Zn + Cu groups (low: Zn20 + Cu12.5, medium: Zn40 + Cu25 and high: Zn60 + Cu37.5) respectively. The control group bucks were maintained mainly on the basal diet without any additional mineral supplementation. Two hundred and forty (240) semen samples were collected from 40 bucks aged 11 months, through electro ejaculator method, processed and analysed for sperm quality parameters both at pre freeze and post-thaw stage. The semen samples were diluted in Tris egg yolk extender, cooled and equilibrated for 4 h at 5 °C, cryopreserved using programmable freezer (PLANER Kryo 360-1.7) and stored at -196 °C. The organic trace minerals (Zn, Cu and Zn + Cu) protected the spermatozoa against the cryoinjury and maintained higher post-thaw semen parameters except in high Zn group. Additional feeding of organic Cu and Zn to bucks had a protective role and resulted in higher sperm liveability, plasma membrane and acrosome integrities, motility and velocity and reduced oxidative stress in supplemented goats (P < 0.05). Copyright © 2018 Elsevier Inc. All rights reserved.

Dietary flax seed oil and/or Vitamin E improve sperm parameters of cloned goats following freezing-thawing.

PubMed

Kargar, Rohollah; Forouzanfar, Mohsen; Ghalamkari, Gholamreza; Nasr Esfahani, Mohammad Hossein

2017-02-01

Semen cryopreservation is affected by individual differences and use of clones animal from the same source is the main tool to eliminate genetic variation. Among many nutrients that are necessary for fertility, essential fatty acids and antioxidants are vital for production of healthy sperm by improving sperm membrane integrity and protecting sperm from oxidative stress. The goal of the current study was to investigate whether a flax seed oil or/and Vitamin E dietary supplementation could improve semen quality of cloned bucks following semen cryopreservation. Accordingly, eight adult cloned Bakhtiari bucks were divided randomly into four groups. Bucks were offered a base diet of hay and concentrate. The concentrate was enriched with flax seed oil, 30 gr/kg body weight/day (OIL), Vitamin E (VIT), 3 gr/kg body weight/day, or combined flax seed oil and the vitamin E (OIL-VIT). The concentrate with no supplements was considered as control group (CONT). Both flax seed oil and Vitamin E supplements were added to the total diet. The bucks were fed with their corresponding diets for a total of 9 weeks while sperm collection was carried out within 10-14 weeks. Ejaculates were diluted with Andromed ® and were frozen in liquid nitrogen. Sperm parameters and reactive oxygen species (ROS) contents were evaluated following freezing/thawing. According to the results of our study, dietary supplementation with flax seed oil, or/and Vitamin E can improve sperm motility, vitality and number of sperm with intact plasma membrane following freezing-thawing. But the degree of improvement in these parameters was significantly higher when Flax seed oil and vitamin E were co-supplemented. Copyright © 2016. Published by Elsevier Inc.

Implementing a Farmers’ Market Incentive Program: Perspectives on the New York City Health Bucks Program

PubMed Central

Wethington, Holly; Olsho, Lauren; Jernigan, Jan; Farris, Rosanne; Walker, Deborah Klein

2013-01-01

Introduction One strategy for lowering the prevalence of obesity is to increase access to and affordability of fruits and vegetables through farmers’ markets. However, little has been documented in the literature on the implementation of such efforts. To address this gap, the Division of Nutrition, Physical Activity, and Obesity (DNPAO) sponsored an evaluation of the New York City Health Bucks program, a farmers’ market coupon incentive program intended to increase access to fresh fruits and vegetables in underserved neighborhoods while supporting local farmers. Methods We conducted a process evaluation of Health Bucks program implementation. We interviewed 6 farmer/vendors, 3 market managers, and 4 program administrators, and collected data on site at 86 farmers’ markets, including surveys of 81 managers and 141 farmer/vendors on their perspectives on promotion and redemption of the incentive coupons; knowledge and attitudes regarding the program; experiences with markets and products; and facilitators and barriers to program participation. Results Results indicate that respondents view Health Bucks as a positive program model. Farmers’ market incentive coupon programs like Health Bucks are one strategy to address the problem of obesity and were associated with higher fruit and vegetable access and purchases in low-income communities. Conclusions This evaluation identified some areas for improving implementation of the Health Bucks program. Farmers’ market incentive programs like Health Bucks may be one avenue to increase access to and affordability of fruits and vegetables among low-income persons. Further research is needed to assess the potential effects of these programs on access and health outcomes. PMID:23987251

Design and dSpace interfacing of current fed high gain dc to dc boost converter for low voltage applications

NASA Astrophysics Data System (ADS)

Mukhopadhyay, Debraj; Das, Subhrajit; Arunkumar, G.; Elangovan, D.; Ragunath, G.

2017-11-01

In this paper a current fed interleaved DC - DC boost converter which has an isolated topology and used for high voltage step up is proposed. A basic DC to DC boost converter converts uncontrolled DC voltage into controlled DC voltage of higher magnitude. Whereas this topology has the advantages of lower input current ripple, lesser output voltage, lesser stress on switches, faster transient response, improved reliability and much lesser electromagnetic emission over the conventional DC to DC boost converter. Most important benefit of this interleaved DC to DC boost converter is much higher efficiency. The input current is divided into two paths, substantially ohmic loss (I2R) and inductor ac loss gets reduced and finally the system achieves much higher efficiency. With recent mandates on energy saving interleaved DC to DC boost converter may be used as a very powerful tool to maintain good power density keeping the input current manageable. Higher efficiency also allows higher switching frequency and as a result the topology becomes more compact and cost friendly. The proposed topology boosts 48v DC to 200 V DC. Switching frequency is 100 kHz and PSIM 9.1 Platform has been used for the simulation.

Consistent prediction of GO protein localization.

PubMed

Spetale, Flavio E; Arce, Debora; Krsticevic, Flavia; Bulacio, Pilar; Tapia, Elizabeth

2018-05-17

The GO-Cellular Component (GO-CC) ontology provides a controlled vocabulary for the consistent description of the subcellular compartments or macromolecular complexes where proteins may act. Current machine learning-based methods used for the automated GO-CC annotation of proteins suffer from the inconsistency of individual GO-CC term predictions. Here, we present FGGA-CC + , a class of hierarchical graph-based classifiers for the consistent GO-CC annotation of protein coding genes at the subcellular compartment or macromolecular complex levels. Aiming to boost the accuracy of GO-CC predictions, we make use of the protein localization knowledge in the GO-Biological Process (GO-BP) annotations to boost the accuracy of GO-CC prediction. As a result, FGGA-CC + classifiers are built from annotation data in both the GO-CC and GO-BP ontologies. Due to their graph-based design, FGGA-CC + classifiers are fully interpretable and their predictions amenable to expert analysis. Promising results on protein annotation data from five model organisms were obtained. Additionally, successful validation results in the annotation of a challenging subset of tandem duplicated genes in the tomato non-model organism were accomplished. Overall, these results suggest that FGGA-CC + classifiers can indeed be useful for satisfying the huge demand of GO-CC annotation arising from ubiquitous high throughout sequencing and proteomic projects.

Survivorship, development, and fecundity of buck moth (Lepidoptera: Saturniidae) on common tree species in the Gulf Coast urban forest

Treesearch

P. J. Martinat; J. D. Solomon; Theodor D. Leininger

1996-01-01

Hemileuca maia maia (Drury), the buck moth, is abundant in urban areas of the Gulf Coast region where it defoliates oaks. However, the extent to which the buck moth can survive on other tree species common in the southern urban forest has not been reported. In the laboratory, the authors studied the suitability and acceptability to larvae of 14 common tree species in...

The Score-Boosting Game.

ERIC Educational Resources Information Center

Popham, W. James

2000-01-01

Teachers everywhere are playing the score-boosting game to raise scores on mandated standardized achievement tests, although five nationally recognized assessments compare student performance instead of measuring classroom learning. Since curriculum standards are often vague and misaligned with assessments, teachers sprinkle instruction with…

How Much Can We Boost IQ and Scholastic Achievement?

ERIC Educational Resources Information Center

Jensen, Arthur R.

The importance and consequences of raising the average ability level (IQ) of the population requires consideration of the ability level that society requires, how the relevant abilities are distributed, and the efficiency of the current educational process. Within the framework of these factors, the document discusses the determinants of mental…

Effect of elemental nano-selenium on semen quality, glutathione peroxidase activity, and testis ultrastructure in male Boer goats.

PubMed

Shi, Li-guang; Yang, Ru-jie; Yue, Wen-bin; Xun, Wen-juan; Zhang, Chun-xiang; Ren, You-she; Shi, Lei; Lei, Fu-lin

2010-04-01

The objective of this experiment is to study the effects of novel elemental nano-selenium in the diet on testicular ultrastructure, semen quality and GSH-Px activity in male goats. Forty-two 2-month-old bucks were offered a total mixed ration which had been supplemented with nano-Se (0.3mg/kg Se) or unsupplemented (the control group only received 0.06mg/kg Se-background), for a period of 12 weeks (from weaning to sexual maturity). Results showed that the testicular Se level, semen glutathione peroxidase and ATPase activity increased significantly in the nano-Se supplementation group compared with control (P<0.05). The semen quality (volume, density, motility and pH) was not affected by added Se in diets, however, the sperm abnormality rate of control bucks was significantly higher than Se supplemented bucks (P<0.05). The testes of 5 goats in each group were examined by transmission electron microscopy (TEM), and showed that in Se-deficient bucks the membrane was damaged, and showed the occurrence of abnormalities in the mitochondria of the midpiece of spermatozoa. In conclusion, selenium deficiency resulted in abnormal spermatozoal mitochondria, and supplementation with nano-Se enhanced the testis Se content, testicular and semen GSH-Px activity, protected the membrane system integrity and the tight arrayment of the midpiece of the mitochondria. Further studies are required to research the novel elemental nano-Se with characterization of bioavailability and toxicity in small ruminants. Copyright 2009 Elsevier B.V. All rights reserved.

Genetic parameters of rabbit semen traits and male fertilising ability.

PubMed

Brun, J M; Sanchez, A; Ailloud, E; Saleil, G; Theau-Clément, M

2016-03-01

This study aimed to estimate genetic parameters for rabbit semen production, semen characteristics and fertilising ability following artificial insemination. It involved five successive batches of 30-36 bucks each, 22 weeks of semen collection, and 11 weeks of semen recording per batch. Semen analyses were based on 2312 ejaculates. A total of 2019 inseminations were performed on 674 females with semen from 236 ejaculates from 128 bucks. Heritability estimates of semen traits ranged from 0.05 to 0.18. At approximately 0.05-0.06 for pH, volume and mass motility, they were higher for concentration (0.10) and the total number of sperms per ejaculate (0.12), and even higher for motility traits based on computer-assisted semen analysis. The percentage of motile sperms had the highest heritability (0.18) and appeared to be a good candidate criterion to select for both sperm number and motility. The heritability estimates were close to zero for all three criteria of fertilising ability: fertility (F), prolificacy (live births, LB) and their product (LB per insemination). A permanent environmental effect of the male seemed to be higher for LB (0.04) than for F (0.01). The rabbit does accounted for approximately 10% of the variance of the three criteria. With respect to the female, the male contribution was negligible for fertility and in a ratio of 4-10 for the number of live births. In our experimental conditions, prolificacy would thus be more highly influenced by the buck than fertility. Copyright © 2016 Elsevier B.V. All rights reserved.

Operation strategy for grid-tied DC-coupling power converter interface integrating wind/solar/battery

NASA Astrophysics Data System (ADS)

Jou, H. L.; Wu, J. C.; Lin, J. H.; Su, W. N.; Wu, T. S.; Lin, Y. T.

2017-11-01

The operation strategy for a small-capacity grid-tied DC-coupling power converter interface (GDPCI) integrating wind energy, solar energy and battery energy storage is proposed. The GDPCI is composed of a wind generator, a solar module set a battery bank, a boost DC-DC power converter (DDPC), a bidirectional DDPC power converter, an AC-DC power converter (ADPC) and a five-level DC-AC inverter (DAI). A solar module set, a wind generator and a battery bank are coupled to the common DC bus through the boost DDPC, the ADPC and the bidirectional DDPC, respectively. For verifying the performance of the GDPCI under different operation modes, computer simulation is carried out by PSIM.

The effect of sawbolt length on the yield of pallet materials from small-diameter hardwood trees

Treesearch

E. Paul Craft

1982-01-01

From poletimber stand thinnings, 52 trees were bucked into 8-foot lengths, and 49 trees were felled and bucked into 10-foot lengths, The 8- and 10-foot pieces were sawed into pallet cants and side lumber suitable for pallet parts. The sawed yield, by tree, from each length category was compared to the predicted yield of the same trees if bucked into 4- and 6-foot bolts...

Create a Sense of Place for the Mobile Learner

ERIC Educational Resources Information Center

Hemmig, William; Johnstone, Brian T.; Montet, Margaret

2012-01-01

"Sense of place" no longer applies only to the physical library. All students are distance learners to one extent or another, and all distance services must be considered as a single virtual learning commons. Librarians at Bucks County (PA) Community College implement and integrate current teaching, learning, virtual reference, and mobile access…

The American Society for Therapeutic Radiology and Oncology (ASTRO) evidence-based review of the role of radiosurgery for malignant glioma

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

Tsao, May N.; Mehta, Minesh P.; Whelan, Timothy J.

2005-09-01

Purpose: To systematically review the evidence for the use of stereotactic radiosurgery or stereotactic fractionated radiation therapy in adult patients with malignant glioma. Methods: Key clinical questions to be addressed in this evidence-based review were identified. Outcomes considered were overall survival, quality of life or symptom control, brain tumor control or response and toxicity. MEDLINE (1990-2004 June Week 2), CANCERLIT (1990-2003), CINAHL (1990-2004 June Week 2), EMBASE (1990-2004 Week 25), and the Cochrane library (2004 issue 2) databases were searched using OVID. In addition, the Physician Data Query clinical trials database, the proceedings of the American Society of Clinical Oncologymore » (1997-2004), ASTRO (1997-2004), and the European Society of Therapeutic Radiology and Oncology (ESTRO) (1997-2003) were searched. Data from the literature search were reviewed and tabulated. This process included an assessment of the level of evidence. Results: For patients with newly diagnosed malignant glioma, radiosurgery as boost therapy with conventional external beam radiation was examined in one randomized trial, five prospective cohort studies, and seven retrospective series. There is Level I evidence that the use of radiosurgery boost followed by external beam radiotherapy and carmustine (BCNU) does not confer benefit with respect to overall survival, quality of life, or patterns of failure as compared with external beam radiotherapy and BCNU. There is Level I-III evidence of toxicity associated with radiosurgery boost as compared with external beam radiotherapy alone. The results of the prospective and retrospective studies may be influenced by selection bias. Radiosurgery used as salvage for recurrent or progressive malignant glioma after conventional external beam radiotherapy failure was reported in zero randomized trials, three prospective cohort studies, and five retrospective series. The available data are sparse and insufficient to make absolute recommendations. Stereotactic fractionated radiation therapy has been reported as boost therapy with external beam radiotherapy for patients with newly diagnosed malignant glioma in only three prospective studies. As primary therapy alone without conventional external beam radiotherapy for newly diagnosed malignant glioma patients, stereotactic fractionated radiation therapy has been reported in only one prospective study. There were only three prospective series and two retrospective studies reported for patients with recurrent or progressive malignant glioma. Conclusions: For patients with malignant glioma, there is Level I-III evidence that the use of radiosurgery boost followed by external beam radiotherapy and BCNU does not confer benefit in terms of overall survival, local brain control, or quality of life as compared with external beam radiotherapy and BCNU. The use of radiosurgery boost is associated with increased toxicity. For patients with malignant glioma, there is insufficient evidence regarding the benefits/harms of using radiosurgery at the time progression or recurrence. There is also insufficient evidence regarding the benefits/harms in the use of stereotactic fractionated radiation therapy for patients with newly diagnosed or progressive/recurrent malignant glioma.« less

Manual harvesting of high population Leucaena stands

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

Pecson, R.D.; Van Den Beldt, R.J.

1983-01-01

Five-year-old giant Leucaena leucocephala, planted at spacing 1x0.5 m, were harvested using bolos (Filipino machetes) and chainsaws. For felling alone, chainsaws took 35% less time than bolos. For the total harvest including delimbing and hauling an average 20 m to the edge of the stand, chainsaws took 20% less time than bolos. Assuming chainsaws are economically viable, it may be advisable to fell with chainsaws in advance of bolo teams that buck and haul. 2 references.

Investigation of the Fisheries of Africa, Buck, and Judd Lakes, Louisiana.

DTIC Science & Technology

1987-10-01

D-A188 978 INVESTIGATION OF THE FISHERIES VVW NJ 7 LAKES LOUISIA A(U) ARMY ENGINEER UATERWiAYS EXPERIMENT STATION VICKSBURG MS ENVIR L G SANDERS ET...MISCELLANEOUS PAPER EL-87-10 INVESTIGATION OF THE FISHERIES OF AFRICA, S BUCK, AND JUDD LAKES, LOUISIANA by AD-A188 978 Larry G. Sanders, John A...0060 ELEMENT NO. NO NO. rCCESSION NO 11 TITLE (Include Security Classification) Investigation of the Fisheries of Africa, Buck, and Judd Lakes

An empirical comparison of several recent epistatic interaction detection methods.

PubMed

Wang, Yue; Liu, Guimei; Feng, Mengling; Wong, Limsoon

2011-11-01

Many new methods have recently been proposed for detecting epistatic interactions in GWAS data. There is, however, no in-depth independent comparison of these methods yet. Five recent methods-TEAM, BOOST, SNPHarvester, SNPRuler and Screen and Clean (SC)-are evaluated here in terms of power, type-1 error rate, scalability and completeness. In terms of power, TEAM performs best on data with main effect and BOOST performs best on data without main effect. In terms of type-1 error rate, TEAM and BOOST have higher type-1 error rates than SNPRuler and SNPHarvester. SC does not control type-1 error rate well. In terms of scalability, we tested the five methods using a dataset with 100 000 SNPs on a 64 bit Ubuntu system, with Intel (R) Xeon(R) CPU 2.66 GHz, 16 GB memory. TEAM takes ~36 days to finish and SNPRuler reports heap allocation problems. BOOST scales up to 100 000 SNPs and the cost is much lower than that of TEAM. SC and SNPHarvester are the most scalable. In terms of completeness, we study how frequently the pruning techniques employed by these methods incorrectly prune away the most significant epistatic interactions. We find that, on average, 20% of datasets without main effect and 60% of datasets with main effect are pruned incorrectly by BOOST, SNPRuler and SNPHarvester. The software for the five methods tested are available from the URLs below. TEAM: http://csbio.unc.edu/epistasis/download.php BOOST: http://ihome.ust.hk/~eeyang/papers.html. SNPHarvester: http://bioinformatics.ust.hk/SNPHarvester.html. SNPRuler: http://bioinformatics.ust.hk/SNPRuler.zip. Screen and Clean: http://wpicr.wpic.pitt.edu/WPICCompGen/. wangyue@nus.edu.sg.

Water resources of southeastern Bucks County, Pennsylvania

USGS Publications Warehouse

Graham, Jack B.; Mangan, John W.; White, Walter F.

1951-01-01

This report has been prepared as a contribution to the development of southeastern Bucks County, Pa. It summarizes available information on the water resources of this 90-square mile area and evaluates current supplies. Future development of the area may change both the available quantity and the quality of the water supply. The effective development of the area demands a continuing knowledge of the water used and the potential quantity and quality of water available from both underground and surface sources. The area is strategically important to a great industrial section of the Bast. Its eastern boundary is a 26-mile segment of the Delaware River along the extreme southeastern border of Bucks County, Pa. (fig. 1). The present.population of the area is about 40,000, including 24,800 in Bristol Borough and Township and 6,770 in Morrisville. The area is traversed by both the Pennsylvania and the Reading Railroads and also by U.S. Highways 1 and 13. These are main transportation routes connecting the great market outlets of Philadelphia and New York. The Delaware River'is navigable from Morrisville to the sea. The area is only a short distance upstream from the Port of Philadelphia, which ranks second only to New York as the most important seaport in the United States. The area is mostly flat, open land 10 to 60 feet above mean sea level. It contains several large Industries, concentrated chiefly in the Bristol area (pi. 1). There are also scattered industries in the Morrisville, Langhorne, and Bensalem areas. However, Bucks County retains some of the characteristics of a farming region. Truck farming and gardening are still carried on to a considerable extent. Along Delaware River below Morrisville the mining of sand and gravel is an Important industry. The facts summarized in this report have been accumulated over a period of 25 years or more by Federal, State, and local agencies in connection with Investigations for other purposes. Most of the data used in this report have been obtained by the United States Geological Survey in cooperation with the Pennsylvania Department of Forests and Waters, the Pennsylvania Department of Internal Affairs, the Pennsylvania Department of Commerce, and State Planning Board, the City of Philadelphia, the Corps of Engineers, and the Interstate Commission on the Delaware River Basin. This report was prepared in the Water Resources Division of the U.S.Geological Survey by Jack B. Qraham, District Geologist; John W. Mangan, District Engineer; and Walter F. White, Jr., District Chemist, under the general direction of C. G. Paulsen, Chief Hydraulic Engineer.

Experimental injury study of children seated behind collapsing front seats in rear impacts.

PubMed

Saczalski, Kenneth J; Sances, Anthony; Kumaresan, Srirangam; Burton, Joseph L; Lewis, Paul R

2003-01-01

In the mid 1990's the U.S. Department of Transportation made recommendations to place children and infants into the rear seating areas of motor vehicles to avoid front seat airbag induced injuries and fatalities. In most rear-impacts, however, the adult occupied front seats will collapse into the rear occupant area and pose another potentially serious injury hazard to the rear-seated children. Since rear-impacts involve a wide range of speeds, impact severity, and various sizes of adults in collapsing front seats, a multi-variable experimental method was employed in conjunction with a multi-level "factorial analysis" technique to study injury potential of rear-seated children. Various sizes of Hybrid III adult surrogates, seated in a "typical" average strength collapsing type of front seat, and a three-year-old Hybrid III child surrogate, seated on a built-in booster seat located directly behind the front adult occupant, were tested at various impact severity levels in a popular "minivan" sled-buck test set up. A total of five test configurations were utilized in this study. Three levels of velocity changes ranging from 22.5 to 42.5 kph were used. The average of peak accelerations on the sled-buck tests ranged from approximately 8.2 G's up to about 11.1 G's, with absolute peak values of just over 14 G's at the higher velocity change. The parameters of the test configuration enabled the experimental data to be combined into a polynomial "injury" function of the two primary independent variables (i.e. front seat adult occupant weight and velocity change) so that the "likelihood" of rear child "injury potential" could be determined over a wide range of the key parameters. The experimentally derived head injury data was used to obtain a preliminary HIC (Head Injury Criteria) polynomial fit at the 900 level for the rear-seated child. Several actual accident cases were compared with the preliminary polynomial fit. This study provides a test efficient, multi-variable, method to compare the injury biomechanical data with actual accident cases.

Targeting MRS-Defined Dominant Intraprostatic Lesions with Inverse-Planned High Dose Rate Brachytherapy

DTIC Science & Technology

2008-06-01

brachytherapy treatment planning has been demonstrated. Using the inverse planning program IPSA , dose escalation of target regions with a higher tumor...algorithm (called IPSA ) was used to generate dose distributions for five different levels of DIL- boost, at least 110%, 120%, 130%, 140% and 150...and LDR, VI Last Generation Radiotherapy Course, São Paulo, Brazil, Oct. 19, 2006. Principles and Clinical Applications of IPSA ; Nucletron

Topological Analysis and Gaussian Decision Tree: Effective Representation and Classification of Biosignals of Small Sample Size.

PubMed

Zhang, Zhifei; Song, Yang; Cui, Haochen; Wu, Jayne; Schwartz, Fernando; Qi, Hairong

2017-09-01

Bucking the trend of big data, in microdevice engineering, small sample size is common, especially when the device is still at the proof-of-concept stage. The small sample size, small interclass variation, and large intraclass variation, have brought biosignal analysis new challenges. Novel representation and classification approaches need to be developed to effectively recognize targets of interests with the absence of a large training set. Moving away from the traditional signal analysis in the spatiotemporal domain, we exploit the biosignal representation in the topological domain that would reveal the intrinsic structure of point clouds generated from the biosignal. Additionally, we propose a Gaussian-based decision tree (GDT), which can efficiently classify the biosignals even when the sample size is extremely small. This study is motivated by the application of mastitis detection using low-voltage alternating current electrokinetics (ACEK) where five categories of bisignals need to be recognized with only two samples in each class. Experimental results demonstrate the robustness of the topological features as well as the advantage of GDT over some conventional classifiers in handling small dataset. Our method reduces the voltage of ACEK to a safe level and still yields high-fidelity results with a short assay time. This paper makes two distinctive contributions to the field of biosignal analysis, including performing signal processing in the topological domain and handling extremely small dataset. Currently, there have been no related works that can efficiently tackle the dilemma between avoiding electrochemical reaction and accelerating assay process using ACEK.

Diesel Combustion and Emission Using High Boost and High Injection Pressure in a Single Cylinder Engine

NASA Astrophysics Data System (ADS)

Aoyagi, Yuzo; Kunishima, Eiji; Asaumi, Yasuo; Aihara, Yoshiaki; Odaka, Matsuo; Goto, Yuichi

Heavy-duty diesel engines have adopted numerous technologies for clean emissions and low fuel consumption. Some are direct fuel injection combined with high injection pressure and adequate in-cylinder air motion, turbo-intercooler systems, and strong steel pistons. Using these technologies, diesel engines have achieved an extremely low CO2 emission as a prime mover. However, heavy-duty diesel engines with even lower NOx and PM emission levels are anticipated. This study achieved high-boost and lean diesel combustion using a single cylinder engine that provides good engine performance and clean exhaust emission. The experiment was done under conditions of intake air quantity up to five times that of a naturally aspirated (NA) engine and 200MPa injection pressure. The adopted pressure booster is an external supercharger that can control intake air temperature. In this engine, the maximum cylinder pressure was increased and new technologies were adopted, including a monotherm piston for endurance of Pmax =30MPa. Moreover, every engine part is newly designed. As the boost pressure increases, the rate of heat release resembles the injection rate and becomes sharper. The combustion and brake thermal efficiency are improved. This high boost and lean diesel combustion creates little smoke; ISCO and ISTHC without the ISNOx increase. It also yields good thermal efficiency.

Maximum power point tracking techniques for wind energy systems using three levels boost converter

NASA Astrophysics Data System (ADS)

Tran, Cuong Hung; Nollet, Frédéric; Essounbouli, Najib; Hamzaoui, Abdelaziz

2018-05-01

This paper presents modeling and simulation of three level Boost DC-DC converter in Wind Energy Conversion System (WECS). Three-level Boost converter has significant advantage compared to conventional Boost. A maximum power point tracking (MPPT) method for a variable speed wind turbine using permanent magnet synchronous generator (PMSG) is also presented. Simulation of three-level Boost converter topology with Perturb and Observe algorithm and Fuzzy Logic Control is implemented in MATLAB/SIMULINK. Results of this simulation show that the system with MPPT using fuzzy logic controller has better performance to the Perturb and Observe algorithm: fast response under changing conditions and small oscillation.

8. DETAIL VIEW OF CONNECTION AT CENTER OF BRIDGE. WELDED ...

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

8. DETAIL VIEW OF CONNECTION AT CENTER OF BRIDGE. WELDED PLATE AND I-BARS ARE 20TH CENTURY REVISIONS. - Bucks County Bridge No. 313, Spanning Delaware Canal at Letchworth Avenue, Yardley, Bucks County, PA

Commercial Buck Converters and Custom Coil Development for the ATLAS Inner Detector Upgrade

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

Dhawan, S.; Lanni, F.; Baker, O.

2010-04-01

A new generation of higher gain commercial buck converters built using advanced short channel CMOS processes has the potential to operate in the Atlas Inner Detector at the Super Large Hadron Collider (sLHC). This approach would inherently be more efficient than the existing practice of locating the power conversion external to the detector. The converters must operate in a large magnetic field and be able to survive both high doses of ionizing radiation and large neutron fluences. The presence of a large magnetic field necessitates the use of an air core inductor which is developed and discussed here. Noise measurementsmore » will be made to investigate the effect of the high frequency switching of the buck converter on the sensitive front end electronics. Radiation hardness of selected buck converters and mosfets will also be reported.« less

Lessons from Successful Schools in Disadvantaged Settings: It's Both What You Do and the Way That You Do It, That's What Gets Results!

ERIC Educational Resources Information Center

James, Chris; Dunning, Gerald; Connolly, Michael; Elliott, Tony

2006-01-01

In the UK, and elsewhere in the world, schools with a higher level of pupil socio-economic disadvantage generally have lower levels of pupil attainment. However, some primary schools in Wales buck this trend. They have both high levels of disadvantage and high levels of attainment. The authors studied 18 of these schools to answer the questions:…

A maximum power point tracking algorithm for photovoltaic applications

NASA Astrophysics Data System (ADS)

Nelatury, Sudarshan R.; Gray, Robert

2013-05-01

The voltage and current characteristic of a photovoltaic (PV) cell is highly nonlinear and operating a PV cell for maximum power transfer has been a challenge for a long time. Several techniques have been proposed to estimate and track the maximum power point (MPP) in order to improve the overall efficiency of a PV panel. A strategic use of the mean value theorem permits obtaining an analytical expression for a point that lies in a close neighborhood of the true MPP. But hitherto, an exact solution in closed form for the MPP is not published. This problem can be formulated analytically as a constrained optimization, which can be solved using the Lagrange method. This method results in a system of simultaneous nonlinear equations. Solving them directly is quite difficult. However, we can employ a recursive algorithm to yield a reasonably good solution. In graphical terms, suppose the voltage current characteristic and the constant power contours are plotted on the same voltage current plane, the point of tangency between the device characteristic and the constant power contours is the sought for MPP. It is subject to change with the incident irradiation and temperature and hence the algorithm that attempts to maintain the MPP should be adaptive in nature and is supposed to have fast convergence and the least misadjustment. There are two parts in its implementation. First, one needs to estimate the MPP. The second task is to have a DC-DC converter to match the given load to the MPP thus obtained. Availability of power electronics circuits made it possible to design efficient converters. In this paper although we do not show the results from a real circuit, we use MATLAB to obtain the MPP and a buck-boost converter to match the load. Under varying conditions of load resistance and irradiance we demonstrate MPP tracking in case of a commercially available solar panel MSX-60. The power electronics circuit is simulated by PSIM software.

Vibration reduction of pneumatic percussive rivet tools: mechanical and ergonomic re-design approaches.

PubMed

Cherng, John G; Eksioglu, Mahmut; Kizilaslan, Kemal

2009-03-01

This paper presents a systematic design approach, which is the result of years of research effort, to ergonomic re-design of rivet tools, i.e. rivet hammers and bucking bars. The investigation was carried out using both ergonomic approach and mechanical analysis of the rivet tools dynamic behavior. The optimal mechanical design parameters of the re-designed rivet tools were determined by Taguchi method. Two ergonomically re-designed rivet tools with vibration damping/isolation mechanisms were tested against two conventional rivet tools in both laboratory and field tests. Vibration characteristics of both types of tools were measured by laboratory tests using a custom-made test fixture. The subjective field evaluations of the tools were performed by six experienced riveters at an aircraft repair shop. Results indicate that the isolation spring and polymer damper are very effective in reducing the overall level of vibration under both unweighted and weighted acceleration conditions. The mass of the dolly head and the housing played a significant role in the vibration absorption of the bucking bars. Another important result was that the duct iron has better vibration reducing capability compared to steel and aluminum for bucking bars. Mathematical simulation results were also consistent with the experimental results. Overall conclusion obtained from the study was that by applying the design principles of ergonomics and by adding vibration damping/isolation mechanisms to the rivet tools, the vibration level can significantly be reduced and the tools become safer and user friendly. The details of the experience learned, design modifications, test methods, mathematical models and the results are included in the paper.

Piaget, Marx, and Buck-Morss on Cognitive Development: A Critique and Reinterpretation

ERIC Educational Resources Information Center

Buss, Allan R.

1977-01-01

Piaget's and Marx's cognitive theories of development are briefly compared and contrasted. This provides background for a critical look at Buck-Morss' interpretation of cross-cultural differences in performance on Piagetian abstract formal reasoning tests. (MS)

9. DETAIL VIEW OF BOTTOM CHORD/FLOOR BEAM/IBAR PIN CONNECTION. WELDED ...

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

9. DETAIL VIEW OF BOTTOM CHORD/FLOOR BEAM/I-BAR PIN CONNECTION. WELDED PLATE AT PIN CONNECTION IS 20TH CENTURY REVISION. - Bucks County Bridge No. 313, Spanning Delaware Canal at Letchworth Avenue, Yardley, Bucks County, PA

CMOS-Compatible SOI MESFETS for Radiation-Hardened DC-to-DC Converters

NASA Technical Reports Server (NTRS)

Thornton, Trevor; Lepkowski, William; Wilk, Seth

2013-01-01

A radiation-tolerant transistor switch has been developed that can operate between 196 and +150 C for DC-to-DC power conversion applications. A prototype buck regulator component was demonstrated to be performing well after a total ionizing dose of 300 krad(Si). The prototype buck converters showed good efficiencies at ultra-high switching speeds in the range of 1 to 10 MHz. Such high switching frequency will enable smaller, lighter buck converters to be developed as part of the next project. Switching regulators are widely used in commercial applications including portable consumer electronics.

Influence of lactation stage and some flock management practices on sensory characteristics of goat milk from Brazilian Saanen breed.

PubMed

de Cássia Ramos do Egypto Queiroga, Rita; Costa, Roberto Germano; Madruga, Marta Suely; de Medeiros, Ariosvaldo Nunes; Dos Santos Garruti, Deborah; Magnani, Marciane; de Souza, Evandro Leite

2016-04-01

This study evaluated the influence of lactation stage (early, middle, late) and management practices (milking hygiene and buck presence) on the sensory attributes of Saanen goat milk. Goats were randomly divided in four groups in respect of different milking sanitary procedures and the presence/absence of the buck in the barn. Milk samples were analyzed for sensory attributes including quantitative descriptive analysis (QDA) and acceptance. The milking hygiene practice caused no significant influence on microbiological parameters. Results of QDA revealed that the buck presence increased the characteristic odor of milk at the middle and late lactation stages. The off-odor and off-flavor descriptors showed a distinct response since a higher intensity of these sensory characteristics was noted in the samples obtained from goats maintained without the buck. Odor and flavor contributed most in characterizing the different samples regardless of the management practice and lactation stage. The acceptance of odor showed to be influenced only by the lactation stage, while the acceptance of flavor was only through the presence of the buck. Odor acceptance correlated negatively to off-odor and off-flavor, suggesting that these two sensory attributes impaired the preference for the aroma of the milk samples. © 2015 Japanese Society of Animal Science.

Glansectomy and Split-thickness Skin Graft for Penile Cancer.

PubMed

Parnham, Arie S; Albersen, Maarten; Sahdev, Varun; Christodoulidou, Michelle; Nigam, Raj; Malone, Peter; Freeman, Alex; Muneer, Asif

2018-02-01

Penile cancer is a rare malignancy that is confined to the glans in up to four out of five cases. Although descriptions of glansectomy exist, there are no contemporary video explanations or large published single centre series. To show the efficacy and safety of glansectomy and split-thickness skin graft (STSG) reconstruction. Data were collected retrospectively for patients identified from surgical theatre diaries between February 2005 and January 2016. 177 patients with histologically proven squamous-cell carcinoma on the glans underwent glansectomy and STSG at a tertiary referral centre in the UK. The median follow-up was 41.4 mo. The skin is incised at the subcoronal level and deepened onto Buck's fascia. Dissection is performed over or under Buck's fascia, depending on suspicion of invasion or risk of disease. The glans is excised and a neoglans is created using a STSG. Local recurrence, cancer-specific survival, overall survival, and complications. Sixteen out of 172 patients (9.3%) experienced local recurrence during the follow-up period. Eighteen out of 174 (10.7%) patients died of penile cancer, while 29 patients in total died during the follow-up period. Of 145 patients, 9% required operative intervention for complications, including graft loss and meatal stenosis. Limitations include the retrospective data collection and the lack of functional and sexual outcomes. Glansectomy and STSG comprise a safe procedure in terms of oncologic control and complications for patients with penile cancer confined to the glans penis. Further studies are required to assess functional and sexual outcomes in these patients. We report on the management of penile cancers confined to the head of the penis using glansectomy and a split-thickness skin graft to recreate the appearance of a glans. This technique is safe and effective, with limited complications. Copyright © 2016. Published by Elsevier B.V.

Optimal design of a vibration-based energy harvester using magnetostrictive material (MsM)

NASA Astrophysics Data System (ADS)

Hu, J.; Xu, F.; Huang, A. Q.; Yuan, F. G.

2011-01-01

In this study, an optimal vibration-based energy harvesting system using magnetostrictive material (MsM) was designed and tested to enable the powering of a wireless sensor. In particular, the conversion efficiency, converting from magnetic to electric energy, is approximately modeled from the magnetic field induced by the beam vibration. A number of factors that affect the output power such as the number of MsM layers, coil design and load matching are analyzed and explored in the design optimization. From the measurements, the open-circuit voltage can reach 1.5 V when the MsM cantilever beam operates at the second natural frequency 324 Hz. The AC output power is 970 µW, giving a power density of 279 µW cm - 3. The attempt to use electrical reactive components (either inductors or capacitors) to resonate the system at any frequency has also been analyzed and tested experimentally. The results showed that this approach is not feasible to optimize the power. Since the MsM device has low output voltage characteristics, a full-wave quadrupler has been designed to boost the rectified output voltage. To deliver the maximum output power to the load, a complex conjugate impedance matching between the load and the MsM device is implemented using a discontinuous conduction mode (DCM) buck-boost converter. The DC output power after the voltage quadrupler reaches 705 µW and the corresponding power density is 202 µW cm - 3. The output power delivered to a lithium rechargeable battery is around 630 µW, independent of the load resistance.

Unlocking the full potential of open innovation in the life sciences through a classification system.

PubMed

Nilsson, Niclas; Minssen, Timo

2018-04-01

A common understanding of expectations and requirements is critical for boosting research-driven business opportunities in open innovation (OI) settings. Transparent communication requires common definitions and standards for OI to align the expectations of both parties. Here, we suggest a five-level classification system for OI models, reflecting the degree of openness. The aim of this classification system is to reduce contract negotiation complexity and times between two parties looking to engage in OI. Systematizing definitions and contractual terms for OI in the life sciences helps to reduce entry barriers and boosts collaborative value generation. By providing a contractual framework with predefined rules, science will be allowed to move more freely, thus maximizing the potential of OI. Copyright © 2018 The Authors. Published by Elsevier Ltd.. All rights reserved.

An Improved Power Quality BIBRED Converter-Based VSI-Fed BLDC Motor Drive

NASA Astrophysics Data System (ADS)

Singh, Bhim; Bist, Vashist

2014-01-01

This paper presents an IHQRR (integrated high-quality rectifier regulator) BIBRED (boost integrated buck rectifier energy storage DC-DC) converter-based VSI (voltage source inverter)-fed BLDC (brushless DC) motor drive. The speed control of BLDC motor is achieved by controlling the DC link voltage of the VSI using a single voltage sensor. This allows VSI to operate in fundamental frequency switching mode for electronic commutation of BLDC motor which reduces the switching losses due to high-frequency switching used in conventional approach of PWM (pulse width modulation)-based VSI-fed BLDC motor drive. A BIBRED converter is operated in a dual-DCM (discontinuous conduction mode) thus using a voltage follower approach for PFC (power factor correction) and DC link voltage control. The performance of the proposed drive is evaluated for improved power quality over a wide range of speed control and supply voltage variation for demonstrating the behavior of proposed drive. The power quality indices thus obtained are within the recommended limits by international PQ (power quality) standards such as IEC 61000-3-2.

Transcranial direct current stimulation (tDCS) to improve naming ability in post-stroke aphasia: A critical review.

PubMed

ALHarbi, Mohammed F; Armijo-Olivo, Susan; Kim, Esther S

2017-08-14

Transcranial Direct Current Stimulation (tDCS) is a non-invasive neuromodulation tool that can be used to influence cortical brain activity to induce measurable behavioral changes. Although there is growing evidence that tDCS combined with behavioural language therapy could boost language recovery in patients with post-stroke aphasia, there is great variability in patient characteristics, treatment protocols, and outcome measures in these studies that poses challenges for analyzing the evidence. The purpose of this study is to critically analyze the methodological rigor of the evidence regarding the use of tDCS for post-stroke anomia. This critical review was conducted by searching four databases (MEDLINE, EMBase, PsycINFO, and CINAHL). Nineteen studies fully met the inclusion criteria. Three critical appraisal tools and Robey and Schultz's (1998) five- phase model for conducting clinical outcome research were adopted to evaluate and analyze the current level of evidence. Methodological issues of the studies were also identified. The current level of evidence for using tDCS for anomia is at the pre-efficacy level with emerging evidence at the efficacy level. Lack of proper evaluation of carry-over effects in cross-over studies, lack of or unclear randomization, allocation concealment, and incomplete data handling were the main methodological issues that could threaten the validity of the tDCS for anomia studies. Several methodological issues have been identified in pre-efficacy studies that pose challenges in determining whether tDCS is a beneficial adjunct to behavioral aphasia therapy. Future studies need to improve the quality of the methods used to investigate the effect of tDCS for anomia. Copyright © 2017 Elsevier B.V. All rights reserved.

Fish population and habitat analysis in Buck Creek, Washington, prior to recolonization by anadromous salmonids after the removal of Condit Dam

USGS Publications Warehouse

Allen, M. Brady; Burkhardt, Jeanette; Munz, Carrie; Connolly, Patrick J.

2012-01-01

We assessed the physical and biotic conditions in the part of Buck Creek, Washington, potentially accessible to anadromous fishes. This creek is a major tributary to the White Salmon River upstream of Condit Dam, which was breached in October 2011. Habitat and fish populations were characterized in four stream reaches. Reach breaks were based on stream gradient, water withdrawals, and fish barriers. Buck Creek generally was confined, with a single straight channel and low sinuosity. Boulders and cobble were the dominant stream substrate, with limited gravel available for spawning. Large-cobble riffles were 83 percent of the available fish habitat. Pools, comprising 15 percent of the surface area, mostly were formed by bedrock with little instream cover and low complexity. Instream wood averaged 6—10 pieces per 100 meters, 80 percent of which was less than 50 centimeters in diameter. Water temperature in Buck Creek rarely exceeded 16 degrees Celsius and did so for only 1 day at river kilometer (rkm) 3 and 11 days at rkm 0.2 in late July and early August 2009. The maximum temperature recorded was 17.2 degrees Celsius at rkm 0.2 on August 2, 2009. Minimum summer discharge in Buck Creek was 3.3 cubic feet per second downstream of an irrigation diversion (rkm 3.1) and 7.7 cubic feet per second at its confluence with the White Salmon River. Rainbow trout (Oncorhynchus mykiss) was the dominant fish species in all reaches. The abundance of age-1 or older rainbow trout was similar between reaches. However, in 2009 and 2010, the greatest abundance of age-0 rainbow trout (8 fish per meter) was in the most downstream reach. These analyses in Buck Creek are important for understanding the factors that may limit fish abundance and productivity, and they will help identify and prioritize potential restoration actions. The data collected constitute baseline information of pre-dam removal conditions that will allow assessment of changes in fish populations now that Condit Dam has been removed and anadromous fish have an opportunity to recolonize Buck Creek.

The Role of Concomitant Radiation Boost in Neoadjuvant Chemoradiotherapy for Locally Advanced Rectal Cancer.

PubMed

Badakhshi, Harun; Ismail, Mahmoud; Boskos, Christos; Zhao, Kuaile; Kaul, David

2017-06-01

This study analyzed the impact of concomitant boost on long-term clinical outcomes in locally advanced rectal cancer. A total of 141 patients (median age=61 years) were treated with neoadjuvant chemoradiotherapy. Median total dose was 50.4 Gy. Forty-three patients received a concomitant boost. Concurrent chemotherapy consisted of 5-fluorouracil (5-FU), given as a 24-h continuous infusion. Mean follow-up was 83.7 months. The 3, 5-, and 10-year overall survival (OS) rates were 91.9%, 84.6%, and 52.9%, respectively. Recurrence-free survival (RFS) rates at 3, 5, and 10 years were 91.4%, 88.9%, and 79.3%, respectively. Metastasis-free survival (MFS) rates at 3, 5, and 10 years were 84.6%, 75.4%, and 49.9%, respectively. Overall, 9.9% of all patients achieved pathological complete response. Down-staging of T- or N-stage was achieved in 55.1% and 41.5% of patients. Multivariate analysis revealed that female sex (p=0.011), concomitant boost-radiotherapy (p=0.014), and the presence of fewer than five positive lymph nodes (p<0.001) were positive predictors of OS. Fewer than five positive lymph nodes was also a positive predictor for RFS (p=0.019). Female gender (p=0.018) and fewer than five positive lymph nodes (p<0.001) were significant predictors for MFS. Our data support the efficacy of preoperative treatment for rectal cancer in terms of local outcomes. Intensified radiotherapy using a concomitant boost has a positive effect on OS. Copyright© 2017, International Institute of Anticancer Research (Dr. George J. Delinasios), All rights reserved.

Development of new microwave-drying and straightening technology for low-value curved timber

Treesearch

John F. Hunt; Hongmei Gu; Philip Walsh; Jerrold E. Winandy

2005-01-01

A considerable amount of small-diameter, branched, or curved timber is currently left standing, bucked and left on the ground, chipped, or burned after logging or thinning operations. Most North American mills are not equipped to handle this low-value material. In many areas of the western United States, such forest residue does not decompose and becomes susceptible to...

Numerical design of an EBIS collector to optimize electron collection and ion extraction

NASA Astrophysics Data System (ADS)

Dietrich, Jürgen

1990-12-01

For the Frankfurt EBIS (R. Becker et al., Nucl. Instr. and Meth. B24/25 (1987) 838, ref. [1]), a new collector was designed using the relativistic electron optics program EGUN (W.B. Herrmannsfeldt, SLAC-331 (1988), ref. [2]) and the magnetic field program INTMAG (R. Becker, Nucl. Instr. and Meth. B42 (1989) 303, ref. [3]). To model the fringing field of the main solenoid, a bucking coil and a cylindrical shim is provided. The current of the bucking coil and the position and shape of the shim are optimized with INTMAG for minimum fringing field to allow expansion of the electron beam by its space charge. The magnetic field data output from INTMAG is directly used as input for EGUN to calculate the electron and ion trajectories. The initial conditions for the trajectories were computed from the paraxial ray equation. Different operation modes of the collector are investigated including the behaviour of secondary electrons.

Flexible Power Distribution Based on Point of Load Converters

NASA Astrophysics Data System (ADS)

Dhallewin, G.; Galiana, D.; Mollard, J. M.; Schaper, W.; Strixner, E.; Tonicello, F.; Triggianese, M.

2014-08-01

Present digital electronic loads require low voltages and suffer from high currents. In addition, they need several different voltage levels to supply the different parts of digital devices like the core, the input/output I/F, etc. Distributed Power Architectures (DPA) with point-of- load (POL) converters (synchronous buck type) offer excellent performance in term of efficiency and load step behaviour. They occupy little PCB area and are well suited for very low voltage (VLV) DC conversion (1V to 3.3V). The paper presents approaches to architectural design of POL based supplies including redundancy and protection as well as the requirements on a European hardware implementation. The main driver of the analysis is the flexibility of each element (DC/DC converter, protection, POL core) to cover a wide range of space applications.

BUCKS LAKE AND CHIPS CREEK ROADLESS AREAS, CALIFORNIA.

USGS Publications Warehouse

Sorensen, Martin L.; Linne, J. Mitchell

1984-01-01

The results of a mineral-resource assessment of the Bucks Lake and Chips Creek Roadless Areas, California indicate several areas with mineral-resource potential. The presence or absence of these potentially auriferous deposits can best be determined by drilling through the relatively thin cover of volcanic rocks.

Creating an Entrepreneurial Mindset

ERIC Educational Resources Information Center

Guth, Douglas J.

2016-01-01

The road from teenage resourcefulness to a real-deal corporate operation was paved by the Bucks Business Association, a student led group at Bucks County Community College (BCCC) that hones student leadership, money management and organizational skills. Community colleges throughout the country are sharpening the startup-minded acumen of their…

69. TILE WORKS UNDER CONSTRUCTION, 1912. SOURCE: FONTHILL MANUSCRIPT COLLECTION, ...

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

69. TILE WORKS UNDER CONSTRUCTION, 1912. SOURCE: FONTHILL MANUSCRIPT COLLECTION, SPRUANCE LIBRARY, BUCKS COUNTY HISTORICAL SOCIETY (HEREAFTER SL/BCHS), UNCATALOGED GLASS PLATE NEGATIVE. - Moravian Pottery & Tile Works, Southwest side of State Route 313 (Swamp Road), Northwest of East Court Street, Doylestown, Bucks County, PA

78 FR 77777 - Qualification of Drivers; Exemption Applications; Vision

Federal Register 2010, 2011, 2012, 2013, 2014

2013-12-24

... vision requirement if the exemptions will provide a level of safety that is equivalent to or greater than... Alex M. Long Charles McDonald Kenneth C. Mead Abdelkhaleq R. Muhammad Eduardo Nunez Michael J... suspension during the 3-year period: Buck J. Barney Charles R. Edwards The following applicant, Victor A...

Monitoring the visitor experience at Buck Island Reef National Monument

Treesearch

Alan R. Graefe; Roger L. Moore

1992-01-01

This paper examines relationships between visitor density levels and perceptions of crowding at a Caribbean coral reef. Reef visitors were more likely to report that the quality of their experience was enhanced, rather than reduced, by their encounters with other visitors. Perceived crowding was related to visitors' previous experience and the location of...

Performance of Hearing Protectors in Impulse Noise

DTIC Science & Technology

2000-09-01

report: ADPO10340 thru ADP010346 UNCLASSIFIED 3-1 Performance of Hearing Protectors in Impulse Noise K. Buck French German Research Institute BP 34...5 rue du G6n~ral Cassagnou 68301 Saint-Louis CEDEX France Summary adapted to the high levels to which the devices will The present paper describes the

Eugenics Past and Present: Remembering Buck v. Bell.

ERIC Educational Resources Information Center

Berson, Michael J.; Cruz, Barbara

2001-01-01

Provides background information about the eugenics movement. Focuses on eugenics in the United States detailing the case, Buck v. Bell, and eugenics in Germany. Explores the present eugenic movement, focusing on "The Bell Curve," China's one child policy, and the use of eugenic sterilizations in the United States and Canada. Includes…

"The Bell Curve" and Carrie Buck: Eugenics Revisited.

ERIC Educational Resources Information Center

Smith, J. David

1995-01-01

The 1994 publication of "The Bell Curve" by R. Herrnstein and C. Murray is compared to other examples of eugenic principles, including the sterilization of "feebleminded" Carrie Buck, family degeneracy studies focusing on lower class Caucasian families, and other works that view the poorest and least educated members of society…

Optimizing heliostat positions with local search metaheuristics using a ray tracing optical model

NASA Astrophysics Data System (ADS)

Reinholz, Andreas; Husenbeth, Christof; Schwarzbözl, Peter; Buck, Reiner

2017-06-01

The life cycle costs of solar tower power plants are mainly determined by the investment costs of its construction. Significant parts of these investment costs are used for the heliostat field. Therefore, an optimized placement of the heliostats gaining the maximal annual power production has a direct impact on the life cycle costs revenue ratio. We present a two level local search method implemented in MATLAB utilizing the Monte Carlo raytracing software STRAL [1] for the evaluation of the annual power output for a specific weighted annual time scheme. The algorithm was applied to a solar tower power plant (PS10) with 624 heliostats. Compared to former work of Buck [2], we were able to improve both runtime of the algorithm and quality of the output solutions significantly. Using the same environment for both algorithms, we were able to reach Buck's best solution with a speed up factor of about 20.

Power inversion design for ocean wave energy harvesting

NASA Astrophysics Data System (ADS)

Talebani, Anwar N.

The needs for energy sources are increasing day by day because of several factors, such as oil depletion, and global climate change due to the higher level of CO2, so the exploration of various renewable energy sources is very promising area of study. The available ocean waves can be utilized as free source of energy as the water covers 70% of the earth surface. This thesis presents the ocean wave energy as a source of renewable energy. By addressing the problem of designing efficient power electronics system to deliver 5 KW from the induction generator to the grid with less possible losses and harmonics as possible and to control current fed to the grid to successfully harvest ocean wave energy. We design an AC-DC full bridge rectifier converter, and a DC-DC boost converter to harvest wave energy from AC to regulated DC. In order to increase the design efficiency, we need to increase the power factor from (0.5-0.6) to 1. This is accomplished by designing the boost converter with power factor correction in continues mode with RC circuit as an input to the boost converter power factor correction. This design results in a phase shift between the input current and voltage of the full bridge rectifier to generate a small reactive power. The reactive power is injected to the induction generator to maintain its functionality by generating a magnetic field in its stator. Next, we design a single-phase pulse width modulator full bridge voltage source DC-AC grid-tied mode inverter to harvest regulated DC wave energy to AC. The designed inverter is modulated by inner current loop, to control current injected to the grid with minimal filter component to maintain power quality at the grid. The simulation results show that our design successfully control the current level fed to the grid. It is noteworthy that the simulated efficiency is higher than the calculated one since we used an ideal switch in the simulated circuit.

Notch-Boosted Domain Wall Propagation in Magnetic Nanowires

NASA Astrophysics Data System (ADS)

Wang, Xiang Rong; Yuan, Hauiyang

Magnetic domain wall (DW) motion along a nanowire underpins many proposals of spintronic devices. High DW propagation velocity is obviously important because it determines the device speed. Thus it is interesting to search for effective control knobs of DW dynamics. We report a counter-intuitive finding that notches in an otherwise homogeneous magnetic nanowire can boost current-induced domain wall (DW) propagation. DW motion in notch-modulated wires can be classified into three phases: 1) A DW is pinned around a notch when the current density is below the depinning current density. 2) DW propagation velocity above the depinning current density is boosted by notches when non-adiabatic spin-transfer torque strength is smaller than the Gilbert damping constant. The boost can be many-fold. 3) DW propagation velocity is hindered when non-adiabatic spin-transfer torque strength is larger than the Gilbert damping constant. This work was supported by Hong Kong GRF Grants (Nos. 163011151 and 605413) and the Grant from NNSF of China (No. 11374249).

Analyzing Von Neumann machines using decentralized symmetries

NASA Astrophysics Data System (ADS)

Fang, Jie

2013-10-01

The artificial intelligence method to e-business is defined not only by the study of fiber-optic cables, but also by the unproven need for vacuum tubes. Given the current status of virtual archetypes, theorists clearly desire the exploration of semaphores, which embodies the compelling principles of cryptoanalysis. We present an algorithm for probabilistic theory (Buck), which we use to disprove that write-back caches can be made decentralized, lossless, and reliable.

Physiological response and semen quality of rabbit bucks supplemented with Moringa leaves ethanolic extract during summer season.

PubMed

El-Desoky, N I; Hashem, N M; Elkomy, A; Abo-Elezz, Z R

2017-09-01

Exposure of rabbit bucks to summer heat stress reduces their homeostasis and semen quality leading to a temporal subfertility. The potentiality of ethanolic extract of Moringa oleifera leaves (M. oleifera ethanolic extract (MLEE)) to reduce negative impacts of heat stress on physiological and semen quality traits was investigated. A total of 28 adult V-line rabbit bucks were randomly distributed among four experimental groups of seven rabbits each. The first group received water (placebo) and served as a control (M0). The other three groups were given orally MLEE at levels of 50 (M50), 100 (M100) and 150 (M150) mg/kg BW every other day for 12 consecutive weeks during the summer season. Chemical constituents of MLEE were detected by gas chromatography/MS. During the experimental period, ambient temperature and relative humidity were recorded daily and were used to estimate temperature and humidity index. Feed intake, BW, rectal temperature were recorded and blood serum biochemical attributes were determined. Semen samples were collected weekly and were analyzed for semen quality traits. Results showed that MLEE contained high percentages of long-chain fatty acids and antioxidant agents. Feed intake and BW were not affected significantly by the treatment, however rectal temperature was decreased significantly by 0.42°C, 0.24°C and 0.40°C in the M50, M100 and M150 groups, respectively, compared with the M0 group. Treatment with 50 mg/kg BW increased concentration of serum albumin (115%; P<0.05), total antioxidant capacity (132%; P<0.05) and testosterone (160%; P=0.098) as well as seminal plasma initial fructose (127%; P=0.092) compared with the control group. Compared with the control, MLEE supplementation with 50, 100 and 150 mg/kg BW increased significantly sperm concentration by 118%, 151% and 158%, sperm progressive motility by 117%, 120% and 118%, sperm viability by 129%, 137% and 127%, sperm normal morphology by 114%, 113% and 114%, intact acrosome sperm by 109% (on average) and sperm with integrated cell membrane by 109%, 123% and 114%, respectively. In conclusion, MLEE supplementation at a level of 50 mg/kg BW could be effectively used to improve heat tolerance, oxidative status and semen quality of rabbit bucks during summer season.

"Class-Bucks": A Motivational Tool to Encourage Active Student Participation during Lectures

ERIC Educational Resources Information Center

de Jager, T.

2013-01-01

The purpose of this study was to ascertain the influence of an extrinsic motivational tool, "class-bucks," on the possibility of improving first year student-teachers' participation in active learning at Tshwane University of Technology in South Africa. Research participants (n=289) were divided into four classes and engaged in this…

75 FR 81715 - Additional Designation of Entities Pursuant to Executive Order 13382

Federal Register 2010, 2011, 2012, 2013, 2014

2010-12-28

... follows: Entities: 1. ASHTEAD SHIPPING COMPANY LIMITED, Manning House, 21 Bucks Road, Douglas IM1 3DA, Man... Square, Pasdaran Avenue, PO Box 19395-1311, Tehran, Iran; Business Registration Document 108116C (Man...: 982120100486 [NPWMD] 2. BYFLEET SHIPPING COMPANY LIMITED, Manning House, 21 Bucks Road, Douglas IM1 3DA, Man...

A Sensorless Predictive Current Controlled Boost Converter by Using an EKF with Load Variation Effect Elimination Function

PubMed Central

Tong, Qiaoling; Chen, Chen; Zhang, Qiao; Zou, Xuecheng

2015-01-01

To realize accurate current control for a boost converter, a precise measurement of the inductor current is required to achieve high resolution current regulating. Current sensors are widely used to measure the inductor current. However, the current sensors and their processing circuits significantly contribute extra hardware cost, delay and noise to the system. They can also harm the system reliability. Therefore, current sensorless control techniques can bring cost effective and reliable solutions for various boost converter applications. According to the derived accurate model, which contains a number of parasitics, the boost converter is a nonlinear system. An Extended Kalman Filter (EKF) is proposed for inductor current estimation and output voltage filtering. With this approach, the system can have the same advantages as sensored current control mode. To implement EKF, the load value is necessary. However, the load may vary from time to time. This can lead to errors of current estimation and filtered output voltage. To solve this issue, a load variation elimination effect elimination (LVEE) module is added. In addition, a predictive average current controller is used to regulate the current. Compared with conventional voltage controlled system, the transient response is greatly improved since it only takes two switching cycles for the current to reach its reference. Finally, experimental results are presented to verify the stable operation and output tracking capability for large-signal transients of the proposed algorithm. PMID:25928061

FIVE-YEAR RESULTS OF ADJUVANT RADIOTHER

PubMed Central

Osa, Etin-Osa O.; DeWyngaert, Keith; Roses, Daniel; Speyer, James; Guth, Amber; Axelrod, Deborah; Kerimian, Maria Fenton; Goldberg, Judith D.; Formenti, Silvia C.

2015-01-01

Purpose/Objective A technique of prone breast radiotherapy delivered by a regimen of accelerated intensity modulated radiation therapy (IMRT) with a concurrent boost to the tumor bed, was developed at our institution. We report the five year results of this approach. Methods and Materials Between 2003–2006, 404 patients with Stage I–II breast cancer were prospectively enrolled into two consecutive protocols, institutional trials 03–30 and 05–181, that used the same regimen of 40.5Gy/15 fractions delivered to the index breast over 3 weeks, with a concomitant daily boost to the tumor bed of 0.5Gy (total dose=48Gy). All patients were treated after segmental mastectomy, had negative margins, and nodal assessment. Patients were set up prone: only if lung or heart volumes were in the field was a supine set-up attempted, and chosen if found to better spare these organs. Results 92% of patients were treated prone, 8% supine. 72% had stage I, 28% stage II invasive breast cancer. In-field lung volume ranged from 0 –228.27cc, mean: 19.65cc. In-field heart volume for left breast cancer patients ranged from 0–21.24cc, mean: 1.59cc. There was no heart in the field for right breast cancer patients. At a median follow-up of five years, the five-year cumulative incidence of isolated ipsilateral breast tumor recurrence was 0.82% (95% CI: 0.65–1.04). The five-year cumulative incidence of regional recurrence was 0.53% (95% CI:0.41–0.69) and the five-year overall cumulative death rate was 1.28% (95% CI: 0.48–3.38). 82% (95% CI: 77–85) of patients judged their final cosmetic result as excellent/good. Conclusions Prone accelerated IMRT with a concomitant boost results in excellent local control, optimal sparing of heart and lung, with good cosmesis. RTOG 10–05, a phase III, multi-institutional, randomized trial is ongoing and is evaluating the equivalence of a similar dose and fractionation approach to standard six weeks radiotherapy with a sequential boost. PMID:24867535

Evaluation of Plaque pH Changes Following Consumption of Health Drinks by Children: A Pilot Study

PubMed Central

Garg, Dhruv; Srikant, N; Bhandary, Meghna; Nayak, Anupama P; Rao, Arathi; Suprabha, BS

2017-01-01

Introduction With increased trend among people to choose a healthy diet, there is an increased consumption of health drinks by children. Thus, it is important to know their cariogenicity. Aim To evaluate the effect of consumption of health drinks viz., Horlicks, Boost and Complan on plaque pH in children. Materials and Methods The study consisted of four groups: Group I (control)- 10% sucrose solution, Group II- Horlicks, Group III- Boost, Group IV- Complan. Samples of plaque from representative teeth were collected and pH was measured using an electrode outside the mouth. After baseline pH was recorded, children were given their respective drinks and were asked to consume slowly over a period of three to five minutes following swish with 20 ml of the test drink for one minute. The pH was then recorded after 10, 20, 30, 40 and 60 minutes of the post consumption period. Obtained values were subjected to one-way ANOVA test for multiple group comparison followed by Post-Hoc Tukey’s test for group wise comparison. Results Twenty minutes after consumption of Complan and Boost, pH was decreased, but not to the critical pH value as in case of sucrose. The pH was found to be slightly increased, 20 minutes post Horlicks consumption. Post 60 minutes consumption of all the drinks including sucrose solution, the pH was increased in comparison to post 20 minutes. However, 60 minutes post consumption of Boost and Horlicks, pH increased above the baseline. Conclusion Consumption of health drinks viz., Complan and Boost did not lower the plaque pH to the level of critical pH. Consumption of Horlicks increased the plaque pH. PMID:28658897

Centaur liquid oxygen boost pump vibration test

NASA Technical Reports Server (NTRS)

Tang, H. M.

1975-01-01

The Centaur LOX boost pump was subjected to both the simulated Titan Centaur proof flight and confidence demonstration vibration test levels. For each test level, both sinusoidal and random vibration tests were conducted along each of the three orthogonal axes of the pump and turbine assembly. In addition to these tests, low frequency longitudinal vibration tests for both levels were conducted. All tests were successfully completed without damage to the boost pump.

76 FR 15366 - Additional Designation of Entities Pursuant to Executive Order 13382

Federal Register 2010, 2011, 2012, 2013, 2014

2011-03-21

..., Manning House, 21 Bucks Road, Douglas IM1 3DA, Man, Isle of; Business Registration Document 003648V (Man..., Man, Isle of; Business Registration Document 003645V (Man, Isle of) issued 2 Mar 2009 [NPWMD] Neuman...] Springthorpe Limited, Manning House, 21 Bucks Road, Douglas IM1 3DA, Man, Isle of; Business Registration...

Formative Assessment as a Vehicle for Changing Classroom Practice in a Specific Cultural Context

ERIC Educational Resources Information Center

Chen, Jingping

2015-01-01

In this commentary, I interpret Xinying Yin and Gayle Ann Buck's collaborative action research from a social-cultural perspective. Classroom implementation of formative assessment is viewed as interaction between this assessment method and the local learning culture. I first identify Yin and Buck's definition of the formative assessment, and then…

Written formative assessment and silence in the classroom

NASA Astrophysics Data System (ADS)

Lee Hang, Desmond Mene; Bell, Beverley

2015-09-01

In this commentary, we build on Xinying Yin and Gayle Buck's discussion by exploring the cultural practices which are integral to formative assessment, when it is viewed as a sociocultural practice. First we discuss the role of assessment and in particular oral and written formative assessments in both western and Samoan cultures, building on the account of assessment practices in the Chinese culture given by Yin and Buck. Secondly, we document the cultural practice of silence in Samoan classroom's which has lead to the use of written formative assessment as in the Yin and Buck article. We also discuss the use of written formative assessment as a scaffold for teacher development for formative assessment. Finally, we briefly discuss both studies on formative assessment as a sociocultural practice.

Comparison of homologous and heterologous prime-boost vaccine approaches using Modified Vaccinia Ankara and soluble protein to induce neutralizing antibodies by the human cytomegalovirus pentamer complex in mice.

PubMed

Chiuppesi, Flavia; Wussow, Felix; Scharf, Louise; Contreras, Heidi; Gao, Han; Meng, Zhuo; Nguyen, Jenny; Barry, Peter A; Bjorkman, Pamela J; Diamond, Don J

2017-01-01

Since neutralizing antibodies (NAb) targeting the human cytomegalovirus (HCMV) pentamer complex (PC) potently block HCMV host cell entry, anti-PC NAb induction is thought to be important for a vaccine formulation to prevent HCMV infection. By developing a vaccine strategy based on soluble PC protein and using a previously generated Modified Vaccinia Ankara vector co-expressing all five PC subunits (MVA-PC), we compared HCMV NAb induction by homologous immunization using prime-boost vaccine regimen employing only PC protein or MVA-PC and heterologous immunization using prime-boost combinations of PC protein and MVA-PC. Utilizing a recently isolated anti-PC NAb, we produced highly pure soluble PC protein that displayed conformational and linear neutralizing epitopes, interfered with HCMV entry, and was recognized by antibodies induced by HCMV during natural infection. Mice vaccinated by different immunization routes with the purified PC protein in combination with a clinically approved adjuvant formulation elicited high-titer and durable HCMV NAb. While MVA-PC and soluble PC protein either alone or in combination elicited robust HCMV NAb, significantly different potencies of these vaccine approaches were observed in dependence on immunization schedule. Using only two immunizations, vaccination with MVA-PC alone or prime-boost combinations of MVA-PC and PC protein was significantly more effective in stimulating HCMV NAb than immunization with PC protein alone. In contrast, with three immunizations, NAb induced by soluble PC protein either alone or combined with two boosts of MVA-PC increased to levels that exceeded NAb titer stimulated by MVA-PC alone. These results provide insights into the potency of soluble protein and MVA to elicit NAb by the HCMV PC via homologous and heterologous prime-boost immunization, which may contribute to develop clinically deployable vaccine strategies to prevent HCMV infection.

Two-stage single-phase grid-connected photovoltaic system with reduced complexity

NASA Astrophysics Data System (ADS)

da Silva, Cintia S.; Motta, Filipe R.; Tofoli, Fernando L.

2011-06-01

This article presents a grid-connected photovoltaic (PV) system using the classical DC-DC buck converter, which is responsible for stepping down the resulting voltage from several series-connected panels. Besides, the structure provides high power factor operation by injecting a quasi-sinusoidal current into the grid, with near no displacement in relation to the line voltage at the point of common coupling among the PV system and the loads. A CSI employing thyristors is cascaded with the DC-DC stage so that AC voltage results. The inverter output voltage level is adjusted by using a low-frequency transformer, which also provides galvanic isolation. The proposed system is described as mathematical approach and design guidelines are presented, providing an overview of the topology. An experimental prototype is also implemented, and relevant results to validate the proposal are discussed.

An optimized posterior axillary boost technique in radiation therapy to supraclavicular and axillary lymph nodes: A comparative study

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

Hernandez, Victor, E-mail: vhernandezmasgrau@gmail.com; Arenas, Meritxell; Müller, Katrin

2013-01-01

To assess the advantages of an optimized posterior axillary (AX) boost technique for the irradiation of supraclavicular (SC) and AX lymph nodes. Five techniques for the treatment of SC and levels I, II, and III AX lymph nodes were evaluated for 10 patients selected at random: a direct anterior field (AP); an anterior to posterior parallel pair (AP-PA); an anterior field with a posterior axillary boost (PAB); an anterior field with an anterior axillary boost (AAB); and an optimized PAB technique (OptPAB). The target coverage, hot spots, irradiated volume, and dose to organs at risk were evaluated and a statisticalmore » analysis comparison was performed. The AP technique delivered insufficient dose to the deeper AX nodes. The AP-PA technique produced larger irradiated volumes and higher mean lung doses than the other techniques. The PAB and AAB techniques originated excessive hot spots in most of the cases. The OptPAB technique produced moderate hot spots while maintaining a similar planning target volume (PTV) coverage, irradiated volume, and dose to organs at risk. This optimized technique combines the advantages of the PAB and AP-PA techniques, with moderate hot spots, sufficient target coverage, and adequate sparing of normal tissues. The presented technique is simple, fast, and easy to implement in routine clinical practice and is superior to the techniques historically used for the treatment of SC and AX lymph nodes.« less

Into the Bowels of Depression: Unravelling Medical Symptoms Associated with Depression by Applying Machine-Learning Techniques to a Community Based Population Sample.

PubMed

Dipnall, Joanna F; Pasco, Julie A; Berk, Michael; Williams, Lana J; Dodd, Seetal; Jacka, Felice N; Meyer, Denny

2016-01-01

Depression is commonly comorbid with many other somatic diseases and symptoms. Identification of individuals in clusters with comorbid symptoms may reveal new pathophysiological mechanisms and treatment targets. The aim of this research was to combine machine-learning (ML) algorithms with traditional regression techniques by utilising self-reported medical symptoms to identify and describe clusters of individuals with increased rates of depression from a large cross-sectional community based population epidemiological study. A multi-staged methodology utilising ML and traditional statistical techniques was performed using the community based population National Health and Nutrition Examination Study (2009-2010) (N = 3,922). A Self-organised Mapping (SOM) ML algorithm, combined with hierarchical clustering, was performed to create participant clusters based on 68 medical symptoms. Binary logistic regression, controlling for sociodemographic confounders, was used to then identify the key clusters of participants with higher levels of depression (PHQ-9≥10, n = 377). Finally, a Multiple Additive Regression Tree boosted ML algorithm was run to identify the important medical symptoms for each key cluster within 17 broad categories: heart, liver, thyroid, respiratory, diabetes, arthritis, fractures and osteoporosis, skeletal pain, blood pressure, blood transfusion, cholesterol, vision, hearing, psoriasis, weight, bowels and urinary. Five clusters of participants, based on medical symptoms, were identified to have significantly increased rates of depression compared to the cluster with the lowest rate: odds ratios ranged from 2.24 (95% CI 1.56, 3.24) to 6.33 (95% CI 1.67, 24.02). The ML boosted regression algorithm identified three key medical condition categories as being significantly more common in these clusters: bowel, pain and urinary symptoms. Bowel-related symptoms was found to dominate the relative importance of symptoms within the five key clusters. This methodology shows promise for the identification of conditions in general populations and supports the current focus on the potential importance of bowel symptoms and the gut in mental health research.

Sliding mode control of direct coupled interleaved boost converter for fuel cell

NASA Astrophysics Data System (ADS)

Wang, W. Y.; Ding, Y. H.; Ke, X.; Ma, X.

2017-12-01

A three phase direct coupled interleaved boost converter (TP-DIBC) was recommended in this paper. This converter has a small unbalance current sharing among the branches of TP-DIBC. An adaptive control law sliding mode control (SMC) is designed for the TP-DIBC. The aim is to 1) reduce ripple output voltage, inductor current and regulate output voltage tightly 2) The total current carried by direct coupled interleaved boost converter (DIBC) must be equally shared between different parallel branches. The efficacy and robustness of the proposed TP-DIBC and adaptive SMC is confirmed via computer simulations using Matlab SimPower System Tools. The simulation result is in line with the expectation.

The Economic Impact of Bucks County Community College on the Local Economy During Fiscal Year 1978-79.

ERIC Educational Resources Information Center

Mahon, Jack

The effects of Bucks County Community College (BCCC) on the local economy during fiscal year (FY) 1979 were investigated in terms of the monies spent in operating BCCC through purchases of goods and services, salaries to college employees, student financial aid expenditures, veterans' benefits, and property taxes paid by college employees, as well…

Conference James F.Buckli

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

None

2008-02-07

L'association du personnel a le plaisir d'accueillir Mons. James F.Buckli, astronaute, né en 1947. Il a participé à la mission Space Lab D1 qui pour la première fois mettait 8 personnes sur orbite.L'ass.du pers. remercie aussi Gordon White(s) de la mission américaine d'avoir permis d'organiser cette conférence

Intensive hardwood log bucker training using HW Buck dramatically improves value recovery

Treesearch

James B. Pickens; Aaron Everett; Scott Noble; John E. Baumgras; Philip A. Araman; Conrad Waniger; Al Steele

2006-01-01

It has long been recognized that inappropriate placement of crosscuts when manufacturing hardwood logs from harvested stems (log bucking) reduces the value of logs produced. Recent studies have estimated losses in the range from 28% to 38% in the lake states region. It has not, however, been clear how to correct the problem. Efforts to improve value recovery have...

Human Immunodeficiency Virus Vaccine Trials

PubMed Central

O’Connell, Robert J.; Kim, Jerome H.; Corey, Lawrence; Michael, Nelson L.

2012-01-01

More than 2 million AIDS-related deaths occurred globally in 2008, and more than 33 million people are living with HIV/AIDS. Despite promising advances in prevention, an estimated 2.7 million new HIV infections occurred in that year, so that for every two patients placed on combination antiretroviral treatment, five people became infected. The pandemic poses a formidable challenge to the development, progress, and stability of global society 30 years after it was recognized. Experimental preventive HIV-1 vaccines have been administered to more than 44,000 human volunteers in more than 187 separate trials since 1987. Only five candidate vaccine strategies have been advanced to efficacy testing. The recombinant glycoprotein (rgp)120 subunit vaccines, AIDSVAX B/B and AIDSVAX B/E, and the Merck Adenovirus serotype (Ad)5 viral-vector expressing HIV-1 Gag, Pol, and Nef failed to show a reduction in infection rate or lowering of postinfection viral set point. Most recently, a phase III trial that tested a heterologous prime-boost vaccine combination of ALVAC-HIV vCP1521 and bivalent rgp120 (AIDSVAX B/E) showed 31% efficacy in protection from infection among community-risk Thai participants. A fifth efficacy trial testing a DNA/recombinant(r) Ad5 prime-boost combination is currently under way. We review the clinical trials of HIV vaccines that have provided insight into human immunogenicity or efficacy in preventing HIV-1 infection. PMID:23209178

Repopulation of interacting tumor cells during fractionated radiotherapy: stochastic modeling of the tumor control probability.

PubMed

Fakir, Hatim; Hlatky, Lynn; Li, Huamin; Sachs, Rainer

2013-12-01

Optimal treatment planning for fractionated external beam radiation therapy requires inputs from radiobiology based on recent thinking about the "five Rs" (repopulation, radiosensitivity, reoxygenation, redistribution, and repair). The need is especially acute for the newer, often individualized, protocols made feasible by progress in image guided radiation therapy and dose conformity. Current stochastic tumor control probability (TCP) models incorporating tumor repopulation effects consider "stem-like cancer cells" (SLCC) to be independent, but the authors here propose that SLCC-SLCC interactions may be significant. The authors present a new stochastic TCP model for repopulating SLCC interacting within microenvironmental niches. Our approach is meant mainly for comparing similar protocols. It aims at practical generalizations of previous mathematical models. The authors consider protocols with complete sublethal damage repair between fractions. The authors use customized open-source software and recent mathematical approaches from stochastic process theory for calculating the time-dependent SLCC number and thereby estimating SLCC eradication probabilities. As specific numerical examples, the authors consider predicted TCP results for a 2 Gy per fraction, 60 Gy protocol compared to 64 Gy protocols involving early or late boosts in a limited volume to some fractions. In sample calculations with linear quadratic parameters α = 0.3 per Gy, α∕β = 10 Gy, boosting is predicted to raise TCP from a dismal 14.5% observed in some older protocols for advanced NSCLC to above 70%. This prediction is robust as regards: (a) the assumed values of parameters other than α and (b) the choice of models for intraniche SLCC-SLCC interactions. However, α = 0.03 per Gy leads to a prediction of almost no improvement when boosting. The predicted efficacy of moderate boosts depends sensitively on α. Presumably, the larger values of α are the ones appropriate for individualized treatment protocols, with the smaller values relevant only to protocols for a heterogeneous patient population. On that assumption, boosting is predicted to be highly effective. Front boosting, apart from practical advantages and a possible advantage as regards iatrogenic second cancers, also probably gives a slightly higher TCP than back boosting. If the total number of SLCC at the start of treatment can be measured even roughly, it will provide a highly sensitive way of discriminating between various models and parameter choices. Updated mathematical methods for calculating repopulation allow credible generalizations of earlier results.

Radiotherapy Breast Boost With Reduced Whole-Breast Dose Is Associated With Improved Cosmesis: The Results of a Comprehensive Assessment From the St. George and Wollongong Randomized Breast Boost Trial

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

Hau, Eric, E-mail: helloerico@yahoo.com; Browne, Lois H.; Khanna, Sam

Purpose: To evaluate comprehensively the effect of a radiotherapy boost on breast cosmetic outcomes after 5 years in patients treated with breast-conserving surgery. Methods: The St. George and Wollongong trial (NCT00138814) randomized 688 patients with histologically proven Tis-2, N 0-1, M0 carcinoma to the control arm of 50 Gy in 25 fractions (342 patients) and the boost arm of 45 Gy in 25 fractions to the whole breast followed by a 16 Gy in 8 fraction electron boost (346 patients). Five-year cosmetic outcomes were assessed by a panel subjectively in 385 patients and objectively using pBRA (relative breast retraction assessment).more » A subset of patients also had absolute BRA measurements. Clinician assessment and patient self-assessment of overall cosmetic and specific items as well as computer BCCT.core analysis were also performed. Results: The boost arm had improved cosmetic overall outcomes as scored by the panel and BCCT.core software with 79% (p = 0.016) and 81% (p = 0.004) excellent/good cosmesis respectively compared with 68% in no-boost arm. The boost arm also had lower pBRA and BRA values with a mean difference of 0.60 and 1.82 mm, respectively, but was not statistically significant. There was a very high proportion of overall excellent/good cosmetic outcome in 95% and 93% in the boost and no-boost arms using patient self-assessment. However, no difference in overall and specific items scored by clinician assessment and patient self-assessment was found. Conclusion: The results show the negative cosmetic effect of a 16-Gy boost is offset by a lower whole-breast dose of 45 Gy.« less

Improved battery charger for electric vehicles

NASA Technical Reports Server (NTRS)

Rippel, W. E.

1981-01-01

Polyphase version of single-phase "boost chopper" significantly reduces ripple and electromagnetic interference (EMI). Drive circuit of n-phase boost chopper incorporates n-phase duty-cycle generator; inductor, transistor, and diode compose chopper which can run on single-phase or three-phase alternating current or on direct current. Device retains compactness and power factors approaching unity, while improving efficiency.

Conference James F.Buckli

ScienceCinema

None

2017-12-09

L'association du personnel a le plaisir d'accueillir Mons. James F.Buckli, astronaute, né en 1947. Il a participé à la mission Space Lab D1 qui pour la première fois mettait 8 personnes sur orbite.L'ass.du pers. remercie aussi Gordon White(s) de la mission américaine d'avoir permis d'organiser cette conférence

Introduction of a Current Waveform, Waveshaping Technique to Limit Conduction Loss in High-Frequency DC-DC Converters Suitable for Space Power

DTIC Science & Technology

1990-06-01

resonant Buck converter 19 ABSTRACT (Continue on reverse if necessary and identify by block number) Space power supply manufacturers have tried to...increase power density and construct smaller, highly efficient power supplies by increasing switching frequency. Incorporation of a power MOSFET as a...Michael, Second Reader \\’-. ohn P. Powers , Chairman Department of Electrical Engineering iii ABSTRACT Space power supply manufacturers have tried to

Adherence and Bonding of the Ion Plated Films.

DTIC Science & Technology

1983-07-01

adhesion strength is, therefore, governed by the physical interactions and van der waals forces yield the lower bound estimates(42). c) Compound interfaces...plasma and 30% for gold- argon plasma, when using high current densities of the or- der of several milliamperes per square centimetere. Buckely et.al...resulted only from ions following the field lines, whereas that on the front surface was the re- sult of both ions and neut ils. In the present work we

Optimization of limestone drains for long- term treatment of acidic mine drainage, Swatara Creek Basin, Schuylkill County, PA

USGS Publications Warehouse

Cravotta, Charles A.; Ward, S.J.; Koury, Daniel J.; Koch, R.D.

2004-01-01

Limestone drains were constructed in 1995, 1997, and 2000 to treat acidic mine drainage (AMD) from the Orchard, Buck Mtn., and Hegins discharges, respectively, in the Swatara Creek Basin, Southern Anthracite Coalfield, east-central Pennsylvania. This report summarizes the construction characteristics and performance of each of the limestone drains on the basis of influent and effluent quality and laboratory tests of variables affecting limestone dissolution rates. Data for influent and effluent indicate substantial alkalinity production by the Orchard and Buck Mtn. limestone drains and only marginal benefits from the Hegins drain. Nevertheless, the annual alkalinity loading rates have progressively declined with age of all three systems. Collapsible-container (cubitainer) testing was conducted to evaluate current scenarios and possible options for reconstruction and maintenance of the limestone drains to optimize their long-term performance. The cubitainer tests indicated dissolution rates for the current configurations that were in agreement with field flux data (net loading) for alkalinity and dissolved calcium. The dissolution rates in cubitainers were larger for closed conditions than open conditions, but the rates were comparable for coated and uncoated limestone for a given condition. Models developed on the basis of the cubitainer testing indicate (1) exponential declines in limestone mass and corresponding alkalinity loading rates with increased age of limestone drains and (2) potential for improved performance with enlargement, complete burial, and/or regular flushing of the systems.

How to boost a low-morale medical practice team: twenty-five strategies.

PubMed

Hills, Laura

2014-01-01

Low morale can decrease productivity and cooperation among medical practice employees, and increase work errors, absenteeism, and turnover. That is why practice managers must be mindful of their employees' morale and develop a toolkit of strategies that they can use to assess and boost waning morale. This article suggests 25 practical and affordable strategies medical practice managers can use to increase their staffs' morale. It explores the high cost of low morale, including five invisible costs that are often overlooked but that nonetheless drain practice resources. Furthermore, this article suggests 25 warning signs of low morale and suggests 10 causes of low morale in the workplace. It also provides practice managers with a quick 10-question quiz to administer to their employees to help them assess employee morale. Finally, this article describes five easy and affordable games practice managers can play with their employees to build camaraderie and teamwork and to increase staff morale.

Organic zinc and copper supplementation on antioxidant protective mechanism and their correlation with sperm functional characteristics in goats.

PubMed

Narasimhaiah, M; Arunachalam, A; Sellappan, S; Mayasula, V K; Guvvala, P R; Ghosh, S K; Chandra, V; Ghosh, J; Kumar, H

2018-06-01

Trace minerals feeding had significant effects on sperm production and fertility with better absorption and proper utilization within the body for optimum reproductive function. Several studies have shown that more influenced trace elements in the diets of animals are copper (Cu) and zinc (Zn). Bucks showing deficiency of this mineral might affect the quality of semen production which in turn would affect the fertility. This experiment was thus designed to test the effects of organic Cu and Zn supplementation on antioxidants enzyme activities and sperm functional attributes in fresh semen of bucks. Forty bucks (n = 40, Aged 5 months) were assigned to ten groups of four animals in each group, supplemented (for a period of 8 months) with different levels of organic Zn: 20 mg (T2), 40 mg (T3) and 60 mg (T4), organic Cu: 12.5 mg (T5), 25 mg (T6), 37.5 mg (T7) and combined organic Zn and Cu: 20 + 12.5 mg (T8), 40 + 25 mg (T9), 60 + 37.5 mg (T10), respectively, per kg dry matter and no additional mineral diet (control; T1). One hundred and sixty semen samples were collected through electro-ejaculator and analysed for sperm quantity, quality, acrosome intactness and plasma membrane integrity and correlated with the catalase, superoxide dismutase, glutathione peroxidase and glutathione reductase enzyme activities in seminal plasma. The results indicated organic Cu and zinc supplemented bucks produced more sperm cells, had higher sperm concentrations, maintained higher (p < .01) sperm livability, plasma membrane and acrosome integrities, more motility and velocity. The increased antioxidant enzyme activities, reduced oxidative stress and lowered lipid peroxidation were positively correlated (p < .05) with the sperm functional attributes. In conclusion, organic Cu and Zn supplement to male goats showed protective roles against oxidative damage and maintained better fresh semen characteristics. © 2018 Blackwell Verlag GmbH.

Top 10 "Secret Writing Tips" to Boost Your Productivity: Part 2

ERIC Educational Resources Information Center

Berk, Ronald A.

2011-01-01

This is the sequel and companion piece to the first five tips published in this journal's winter 2010 issue. To recap, the first five tips are: (1) Write Everyday; (2) Write Everywhere; (3) Conquer Distractions and Interruptions; (4) Write for a Niche; and (5) Write with a Purpose. Now, in this article, the other five tips are discussed: (6) Write…

Transformer current sensor for superconducting magnetic coils

DOEpatents

Shen, Stewart S.; Wilson, C. Thomas

1988-01-01

A transformer current sensor having primary turns carrying a primary current for a superconducting coil and secondary turns only partially arranged within the primary turns. The secondary turns include an active winding disposed within the primary turns and a dummy winding which is not disposed in the primary turns and so does not experience a magnetic field due to a flow of current in the primary turns. The active and dummy windings are wound in opposite directions or connected in series-bucking relationship, and are exposed to the same ambient magnetic field. Voltages which might otherwise develop in the active and dummy windings due to ambient magnetic fields thus cancel out. The resultant voltage is purely indicative of the rate of change of current flowing in the primary turns.

Artificial Neural Identification and LMI Transformation for Model Reduction-Based Control of the Buck Switch-Mode Regulator

NASA Astrophysics Data System (ADS)

Al-Rabadi, Anas N.

2009-10-01

This research introduces a new method of intelligent control for the control of the Buck converter using newly developed small signal model of the pulse width modulation (PWM) switch. The new method uses supervised neural network to estimate certain parameters of the transformed system matrix [Ã]. Then, a numerical algorithm used in robust control called linear matrix inequality (LMI) optimization technique is used to determine the permutation matrix [P] so that a complete system transformation {[B˜], [C˜], [Ẽ]} is possible. The transformed model is then reduced using the method of singular perturbation, and state feedback control is applied to enhance system performance. The experimental results show that the new control methodology simplifies the model in the Buck converter and thus uses a simpler controller that produces the desired system response for performance enhancement.

Adaptive Control for Buck Power Converter Using Fixed Point Inducting Control and Zero Average Dynamics Strategies

NASA Astrophysics Data System (ADS)

Hoyos Velasco, Fredy Edimer; García, Nicolás Toro; Garcés Gómez, Yeison Alberto

In this paper, the output voltage of a buck power converter is controlled by means of a quasi-sliding scheme. The Fixed Point Inducting Control (FPIC) technique is used for the control design, based on the Zero Average Dynamics (ZAD) strategy, including load estimation by means of the Least Mean Squares (LMS) method. The control scheme is tested in a Rapid Control Prototyping (RCP) system based on Digital Signal Processing (DSP) for dSPACE platform. The closed loop system shows adequate performance. The experimental and simulation results match. The main contribution of this paper is to introduce the load estimator by means of LMS, to make ZAD and FPIC control feasible in load variation conditions. In addition, comparison results for controlled buck converter with SMC, PID and ZAD-FPIC control techniques are shown.

Comparison of methods for the implementation of genome-assisted evaluation of Spanish dairy cattle.

PubMed

Jiménez-Montero, J A; González-Recio, O; Alenda, R

2013-01-01

The aim of this study was to evaluate methods for genomic evaluation of the Spanish Holstein population as an initial step toward the implementation of routine genomic evaluations. This study provides a description of the population structure of progeny tested bulls in Spain at the genomic level and compares different genomic evaluation methods with regard to accuracy and bias. Two bayesian linear regression models, Bayes-A and Bayesian-LASSO (B-LASSO), as well as a machine learning algorithm, Random-Boosting (R-Boost), and BLUP using a realized genomic relationship matrix (G-BLUP), were compared. Five traits that are currently under selection in the Spanish Holstein population were used: milk yield, fat yield, protein yield, fat percentage, and udder depth. In total, genotypes from 1859 progeny tested bulls were used. The training sets were composed of bulls born before 2005; including 1601 bulls for production and 1574 bulls for type, whereas the testing sets contained 258 and 235 bulls born in 2005 or later for production and type, respectively. Deregressed proofs (DRP) from January 2009 Interbull (Uppsala, Sweden) evaluation were used as the dependent variables for bulls in the training sets, whereas DRP from the December 2011 DRPs Interbull evaluation were used to compare genomic predictions with progeny test results for bulls in the testing set. Genomic predictions were more accurate than traditional pedigree indices for predicting future progeny test results of young bulls. The gain in accuracy, due to inclusion of genomic data varied by trait and ranged from 0.04 to 0.42 Pearson correlation units. Results averaged across traits showed that B-LASSO had the highest accuracy with an advantage of 0.01, 0.03 and 0.03 points in Pearson correlation compared with R-Boost, Bayes-A, and G-BLUP, respectively. The B-LASSO predictions also showed the least bias (0.02, 0.03 and 0.10 SD units less than Bayes-A, R-Boost and G-BLUP, respectively) as measured by mean difference between genomic predictions and progeny test results. The R-Boosting algorithm provided genomic predictions with regression coefficients closer to unity, which is an alternative measure of bias, for 4 out of 5 traits and also resulted in mean squared errors estimates that were 2%, 10%, and 12% smaller than B-LASSO, Bayes-A, and G-BLUP, respectively. The observed prediction accuracy obtained with these methods was within the range of values expected for a population of similar size, suggesting that the prediction method and reference population described herein are appropriate for implementation of routine genome-assisted evaluations in Spanish dairy cattle. R-Boost is a competitive marker regression methodology in terms of predictive ability that can accommodate large data sets. Copyright © 2013 American Dairy Science Association. Published by Elsevier Inc. All rights reserved.

Evaluating Bang for the Buck: A Cost-Effectiveness Comparison Between Individual Interviews and Focus Groups Based on Thematic Saturation Levels

ERIC Educational Resources Information Center

Namey, Emily; Guest, Greg; McKenna, Kevin; Chen, Mario

2016-01-01

Evaluators often use qualitative research methods, yet there is little evidence on the comparative cost-effectiveness of the two most commonly employed qualitative methods--in-depth interviews (IDIs) and focus groups (FGs). We performed an inductive thematic analysis of data from 40 IDIs and 40 FGs on the health-seeking behaviors of African…

Compensated gain control circuit for buck regulator command charge circuit

DOEpatents

Barrett, David M.

1996-01-01

A buck regulator command charge circuit includes a compensated-gain control signal for compensating for changes in the component values in order to achieve optimal voltage regulation. The compensated-gain control circuit includes an automatic-gain control circuit for generating a variable-gain control signal. The automatic-gain control circuit is formed of a precision rectifier circuit, a filter network, an error amplifier, and an integrator circuit.

Compensated gain control circuit for buck regulator command charge circuit

DOEpatents

Barrett, D.M.

1996-11-05

A buck regulator command charge circuit includes a compensated-gain control signal for compensating for changes in the component values in order to achieve optimal voltage regulation. The compensated-gain control circuit includes an automatic-gain control circuit for generating a variable-gain control signal. The automatic-gain control circuit is formed of a precision rectifier circuit, a filter network, an error amplifier, and an integrator circuit. 5 figs.

Nanolaminated Permalloy Core for High-Flux, High-Frequency Ultracompact Power Conversion

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

Kim, J; Kim, M; Galle, P

2013-09-01

Metallic magnetic materials have desirable magnetic properties, including high permeability, and high saturation flux density, when compared with their ferrite counterparts. However, eddy-current losses preclude their use in many switching converter applications, due to the challenge of simultaneously achieving sufficiently thin laminations such that eddy currents are suppressed (e.g., 500 nm-1 mu m for megahertz frequencies), while simultaneously achieving overall core thicknesses such that substantial power can be handled. A CMOS-compatible fabrication process based on robot-assisted sequential electrodeposition followed by selective chemical etching has been developed for the realization of a core of substantial overall thickness (tens to hundreds ofmore » micrometers) comprised of multiple, stacked permalloy (Ni80Fe20) nanolaminations. Tests of toroidal inductors with nanolaminated cores showed negligible eddy-current loss relative to total core loss even at a peak flux density of 0.5 T in the megahertz frequency range. To illustrate the use of these cores, a buck power converter topology is implemented with switching frequencies of 1-2 MHz. Power conversion efficiency greater than 85% with peak operating flux density of 0.3-0.5 T in the core and converter output power level exceeding 5 W was achieved.« less

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

Turley, Jessica; Claridge Mackonis, Elizabeth

To evaluate in-field megavoltage (MV) imaging of simultaneously integrated boost (SIB) breast fields to determine its feasibility in treatment verification for the SIB breast radiotherapy technique, and to assess whether the current-imaging protocol and treatment margins are sufficient. For nine patients undergoing SIB breast radiotherapy, in-field MV images of the SIB fields were acquired on days that regular treatment verification imaging was performed. The in-field images were matched offline according to the scar wire on digitally reconstructed radiographs. The offline image correction results were then applied to a margin recipe formula to calculate safe margins that account for random andmore » systematic uncertainties in the position of the boost volume when an offline correction protocol has been applied. After offline assessment of the acquired images, 96% were within the tolerance set in the current department-imaging protocol. Retrospectively performing the maximum position deviations on the Eclipse™ treatment planning system demonstrated that the clinical target volume (CTV) boost received a minimum dose difference of 0.4% and a maximum dose difference of 1.4% less than planned. Furthermore, applying our results to the Van Herk margin formula to ensure that 90% of patients receive 95% of the prescribed dose, the calculated CTV margins were comparable to the current departmental procedure used. Based on the in-field boost images acquired and the feasible application of these results to the margin formula the current CTV-planning target volume margins used are appropriate for the accurate treatment of the SIB boost volume without additional imaging.« less

Low Temperature Operation of a Switching Power Converter

NASA Technical Reports Server (NTRS)

Anglada-Sanchez, Carlos R.; Perez-Feliciano, David; Ray, Biswajit

1997-01-01

The low temperature operation of a 48 W, 50 kHz, 36/12 V pulse width modulated (PWM) buck de-de power converter designed with standard commercially available components and devices is reported. The efficiency of the converter increased from 85.6% at room temperature (300 K) to 92.0% at liquid nitrogen temperature (77 K). The variation of power MOSFET, diode rectifier, and output filter inductor loss with temperature is discussed. Relevant current, voltage. and power waveforms are also included.

Cellular Mechanisms of Transcranial Direct Current Stimulation

DTIC Science & Technology

2016-07-14

32 Section 3 Electrical stimulation accelerates and boosts the capacity for synaptic learning ...................... 50 Section 4...Section 3: tDCS is thought to boost the learning of tasks or therapy applied at the same time. We provide a cellular mechanism for this. Moreover, we...show that thus “boosting” is specific to the trained task. [Aim 2] Section 4: tDCS is though to boost learning by promoting synaptic plasticity. We

The effect of mode and context on survey results: Analysis of data from the Health Survey for England 2006 and the Boost Survey for London

PubMed Central

2010-01-01

Background Health-related data at local level could be provided by supplementing national health surveys with local boosts. Self-completion surveys are less costly than interviews, enabling larger samples to be achieved for a given cost. However, even when the same questions are asked with the same wording, responses to survey questions may vary by mode of data collection. These measurement differences need to be investigated further. Methods The Health Survey for England in London ('Core') and a London Boost survey ('Boost') used identical sampling strategies but different modes of data collection. Some data were collected by face-to-face interview in the Core and by self-completion in the Boost; other data were collected by self-completion questionnaire in both, but the context differed. Results were compared by mode of data collection using two approaches. The first examined differences in results that remained after adjusting the samples for differences in response. The second compared results after using propensity score matching to reduce any differences in sample composition. Results There were no significant differences between the two samples for prevalence of some variables including long-term illness, limiting long-term illness, current rates of smoking, whether participants drank alcohol, and how often they usually drank. However, there were a number of differences, some quite large, between some key measures including: general health, GHQ12 score, portions of fruit and vegetables consumed, levels of physical activity, and, to a lesser extent, smoking consumption, the number of alcohol units reported consumed on the heaviest day of drinking in the last week and perceived social support (among women only). Conclusion Survey mode and context can both affect the responses given. The effect is largest for complex question modules but was also seen for identical self-completion questions. Some data collected by interview and self-completion can be safely combined. PMID:20868528

Evaluation of hormone-free protocols based on the "male effect" for artificial insemination in lactating goats during seasonal anestrus.

PubMed

Pellicer-Rubio, Maria-Teresa; Boissard, Karine; Forgerit, Yvonnick; Pougnard, Jean Louis; Bonné, Jean Luc; Leboeuf, Bernard

2016-03-15

Goat estrous and ovulatory responses to the "male effect" were characterized to determine the time range over which fertile ovulations occur after buck exposure. The results were used to explore the efficacy of different hormone-free artificial insemination (AI) protocols aimed at diminishing the number of inseminations needed to optimize fertility. Adult bucks and does were exposed to artificially long days during winter and then exposed to a natural photoperiod before buck exposure (Day 0). Most goats (>70%) ovulated twice, developing a short cycle followed by a normal cycle over 13 days after buck exposure. Among them, 21% were in estrus at the short cycle and 94% at the normal cycle. This second ovulation occurred within 48 hours of Day 6 and was the target for AI protocols. In protocol A (n = 79), goats were inseminated 12 hours after estrus detection from Day 5 to Day 9. Up to six AI times over 4 days were needed to inseminate goats in estrus. Forty-nine percent of the inseminated goats kidded. In protocol B (n = 145), estrus detection started on Day 5. The earlier (group 1) and later (group 2) buck-marked goats received one single insemination at fixed times on Days 6.5 or 7 and 8, respectively; unmarked goats (group 3) were inseminated along with group 2. In protocol C (n = 153), goats were inseminated twice on Days 6.5 or 7 and 8 without needing to detect estrus. Goats induced to ovulate by hormonal treatment were used as the control (n = 319). Fertility was lower in protocol B than in protocol C and controls (47% vs. 58% and 65% kidding; P ≤ 0.05), whereas this was higher in buck-marked goats than in unmarked ones (64% vs. 33%; P ≤ 0.05). In protocol B, fertility can increase (>60%) when only goats coming into estrus are inseminated. The best kidding rate (∼70%) was achieved when does were inseminated within 24 hours of the LH surge. Protocols involving insemination on Day 7 instead of Day 6.5 led to more goats being inseminated during this favorable time. Copyright © 2016 Elsevier Inc. All rights reserved.

Combining Long-Term Watershed Monitoring at Buck Creek with Spatially Extensive Ecosystem Data to Understand the Processes of Acid Rain Effects and Recovery

NASA Astrophysics Data System (ADS)

Lawrence, G. B.; Ross, D. S.; Sullivan, T. J.; McDonnell, T. C.; Bailey, S. W.; Dukett, J. E.

2014-12-01

The Buck Creek Monitoring Watershed, in the western Adirondack Region of New York, has provided long-term data back to 1982 for tracking acid rain effects and recovery, and for supporting fundamental research on environmental change. At Buck Creek, monitoring acidic deposition effects as they worsened, then diminished, has advanced our understanding of key biogeochemical processes such as Al mobilization. Although Al mobilization has been one of the primary adverse effects of acidic deposition, in the recovery phase it is now affecting terrestrial and aquatic ecosystems in new ways that could be both positive and negative, as soils and surface waters respond to further declines in acidic deposition. Using stream Al measurements from Buck Creek over varying seasons and flows, a new index, the base cation surplus (BCS), was developed to account for dissolved organic carbon (DOC) effects on the relationship between ANC and inorganic Al. Mobilization of inorganic Al, the form toxic to biota, occurs below a BCS of zero, regardless of DOC concentrations. Soil and stream data from Adirondack surveys showed that a BCS value of zero corresponds to a soil base saturation value in the B horizon of approximately 12%. Additional Adirondack survey work indicated that, where sugar maple stands grew in soils with base saturation values below 12%, seedling regeneration was nearly zero, suggesting a link between Al mobilization and impairment of tree regeneration. In recovering Adirondack lakes, the BCS was also used to show that increasing trends in DOC were accelerating decreases of inorganic Al beyond what would be expected from the increasing trends of ANC. Similar decreases of inorganic Al in Buck Creek, were coupled with increases in organic Al concentrations, which resulted in no trend in total Al concentrations despite a strong increase in pH. Sampling of Buck Creek soils in 1997, and again in 2009-2010, indicated a substantial decrease in forest floor exchangeable Al, of which approximately 85% was accounted for by stream export through leaching of exchangeable Al from soil to stream. Changes in the chemistry of the upper B horizon also suggest the possibility that recovery from acidification is accelerating podzolization in these soils.

Modelling and Simulation of Grid Connected SPV System with Active Power Filtering Features

NASA Astrophysics Data System (ADS)

Saroha, Jaipal; Pandove, Gitanjali; Singh, Mukhtiar

2017-09-01

In this paper, the detailed simulation studies for a grid connected solar photovoltaic system (SPV) have been presented. The power electronics devices like DC-DC boost converter and grid interfacing inverter are most important components of proposed system. Here, the DC-DC boost converter is controlled to extract maximum power out of SPV under different irradiation levels, while the grid interfacing inverter is utilized to evacuate the active power and feed it into grid at synchronized voltage and frequency. Moreover, the grid interfacing inverter is also controlled to sort out the issues related to power quality by compensating the reactive power and harmonics current component of nearby load at point of common coupling. Besides, detailed modeling of various component utilized in proposed system is also presented. Finally, extensive simulations have been performed under different irradiation levels with various kinds of load to validate the aforementioned claims. The overall system design and simulation have been performed by using Sim Power System toolbox available in the library of MATLAB.

New approaches to provide ride-through for critical loads in electric power distribution systems

NASA Astrophysics Data System (ADS)

Montero-Hernandez, Oscar C.

2001-07-01

The extensive use of electronic circuits has enabled modernization, automation, miniaturization, high quality, low cost, and other achievements regarding electric loads in the last decades. However, modern electronic circuits and systems are extremely sensitive to disturbances from the electric power supply. In fact, the rate at which these disturbances happen is considerable as has been documented in recent years. In response to the power quality concerns presented previously, this dissertation is proposing new approaches to provide ride-through for critical loads during voltage disturbances with emphasis on voltage sags. In this dissertation, a new approach based on an AC-DC-AC system is proposed to provide ride-through for critical loads connected in buildings and/or an industrial system. In this approach, a three-phase IGBT inverter with a built in Dc-link voltage regulator is suitably controlled along with static by-pass switches to provide continuous power to critical loads. During a disturbance, the input utility source is disconnected and the power from the inverter is connected to the load. The remaining voltage in the AC supply is converted to DC and compensated before being applied to the inverter and the load. After detecting normal utility conditions, power from the utility is restored to the critical load. In order to achieve an extended ride-through capability a second approach is introduced. In this case, the Dc-link voltage regulator is performed by a DC-DC Buck-Boost converter. This new approach has the capability to mitigate voltage variations below and above the nominal value. In the third approach presented in this dissertation, a three-phase AC to AC boost converter is investigated. This converter provides a boosting action for the utility input voltages, right before they are applied to the load. The proposed Pulse Width Modulation (PWM) control strategy ensures independent control of each phase and compensates for both single-phase or poly-phase voltage sags. Algorithms capable of detecting voltage disturbances such as voltage sags, voltage swells, flicker, frequency change, and harmonics in a fast and reliable way are investigated and developed in this dissertation as an essential part of the approaches previously described. Simulation and experimental work has been done to validate the feasibility of all approaches under the most common voltage disturbances such as single-phase voltage sags and three-phase voltage sags.

Supply Chain Management Model for Modular or Flexible Optimally Manned Ships

DTIC Science & Technology

2014-03-01

Navy’s New Class of Warships: Big Bucks, Little Bang .” Battleland. Accessed October 3, 2013. http://nation.time.com/2012/10/05/the-navys-new-class-of...warships- big -bucks- little- bang /. Strauch, F. C. n.d. ARROWS Model Evaluation. Project Number N9324-B11-4135, Mechanicsburg, PA: Navy Fleet Material...existing models to determine which one could be suitable for altering to meet the stakeholders’ requirements. Modeling and simulation was used to

Semen variables and sperm membrane protein profile of Saanen bucks ( Capra hircus) in dry and rainy seasons of the northeastern Brazil (3°S)

NASA Astrophysics Data System (ADS)

van Tilburg, M. F.; Salles, M. G. F.; Silva, M. M.; Moreira, R. A.; Moreno, F. B.; Monteiro-Moreira, A. C. O.; Martins, J. A. M.; Cândido, M. J. D.; Araújo, A. A.; Moura, A. A. A.

2015-05-01

The Saanen is a highly productive breed, and for this reason, it has been raised in Brazil, but mostly under climate conditions completely different from where the breed originated. The objective of this study was to investigate variations in semen parameters and sperm membrane proteins from Saanen bucks ( n = 7) raised in Northeastern Brazil, during dry season (September, October, and November) and rainy season (March, April, and May). We showed that during the dry season, sperm motility, concentration, and the percentage of normal sperm decreased as compared to the rainy season. Rectal temperatures of bucks had no significant ( p > 0.05) variations during the dry and rainy seasons. However, temperatures of left and right skin testis were higher ( p < 0.05) during the dry as compared to the rainy season. Expression of three proteins (lysine-specific demethylase 5D, adenosine triphosphate (ATP) synthase subunit d, and radial spoke head protein 9 homolog) in sperm membrane were more intense in rainy season and only one protein (cytosol aminopeptidase) had greater expression in the dry season of the year. Our results show that mechanisms of testicular thermoregulation of Saanen bucks did not prevent a decrease in seminal parameters during the dry season. This deterioration may be related to reduced expression of proteins associated with important functions in sperm membrane.

Double Up Food Bucks program effects on SNAP recipients' fruit and vegetable purchases.

PubMed

Steele-Adjognon, Marie; Weatherspoon, Dave

2017-12-12

To encourage the consumption of more fresh fruits and vegetables, the 2014 United Sates Farm Bill allocated funds to the Double Up Food Bucks Program. This program provided Supplemental Nutrition Assistance Program beneficiaries who spent $10 on fresh fruits and vegetables, in one transaction, with a $10 gift card exclusively for Michigan grown fresh fruits and vegetables. This study analyzes how fruit and vegetable expenditures, expenditure shares, variety and purchase decisions were affected by the initiation and conclusion, as well as any persistent effects of the program. Changes in fruit and vegetable purchase behaviors due to Double Up Food Bucks in a supermarket serving a low-income, predominantly Hispanic community in Detroit, Michigan were evaluated using a difference in difference fixed effects estimation strategy. We find that the Double Up Food Bucks program increased vegetable expenditures, fruit and vegetable expenditure shares, and variety of fruits and vegetables purchased but the effects were modest and not sustainable without the financial incentive. Fruit expenditures and the fruit and vegetable purchase decision were unaffected by the program. This study provides valuable insight on how a nutrition program influences a low-income, urban, Hispanic community's fruit and vegetable purchase behavior. Policy recommendations include either removing or lowering the purchase hurdle for incentive eligibility and dropping the Michigan grown requirement to better align with the customers' preferences for fresh fruits and vegetables.

Application of Distributed DC/DC Electronics in Photovoltaic Systems

NASA Astrophysics Data System (ADS)

Kabala, Michael

In a typical residential, commercial or utility grade photovoltaic (PV) system, PV modules are connected in series and in parallel to form an array that is connected to a standard DC/AC inverter, which is then connected directly to the grid. This type of standard installation; however, does very little to maximize the energy output of the solar array if certain conditions exist. These conditions could include age, temperature, irradiance and other factors that can cause mismatch between PV modules in an array that severely cripple the output power of the system. Since PV modules are typically connected in series to form a string, the output of the entire string is limited by the efficiency of the weakest module. With PV module efficiencies already relatively low, it is critical to extract the maximum power out of each module in order to make solar energy an economically viable competitor to oil and gas. Module level DC/DC electronics with maximum power point (MPP) tracking solves this issue by decoupling each module from the string in order for the module to operate independently of the geometry and complexity of the surrounding system. This allows each PV module to work at its maximum power point by transferring the maximum power the module is able to deliver directly to the load by either boosting (stepping up) the voltage or bucking (stepping down) the voltage. The goal of this thesis is to discuss the development of a per-module DC/DC converter in order to maximize the energy output of a PV module and reduce the overall cost of the system by increasing the energy harvest.

Transcutaneous immunization with cross-reacting material CRM(197) of diphtheria toxin boosts functional antibody levels in mice primed parenterally with adsorbed diphtheria toxoid vaccine.

PubMed

Stickings, Paul; Peyre, Marisa; Coombes, Laura; Muller, Sylviane; Rappuoli, Rino; Del Giudice, Giuseppe; Partidos, Charalambos D; Sesardic, Dorothea

2008-04-01

Transcutaneous immunization (TCI) capitalizes on the accessibility and immunocompetence of the skin, elicits protective immunity, simplifies vaccine delivery, and may be particularly advantageous when frequent boosting is required. In this study we examined the potential of TCI to boost preexisting immune responses to diphtheria in mice. The cross-reacting material (CRM(197)) of diphtheria toxin was used as the boosting antigen and was administered alone or together with either one of two commonly used mucosal adjuvants, cholera toxin (CT) and a partially detoxified mutant of heat-labile enterotoxin of Escherichia coli (LTR72). We report that TCI with CRM(197) significantly boosted preexisting immune responses elicited after parenteral priming with aluminum hydroxide-adsorbed diphtheria toxoid (DTxd) vaccine. In the presence of LTR72 as an adjuvant, toxin-neutralizing antibody titers were significantly higher than those elicited by CRM(197) alone and were comparable to the functional antibody levels induced after parenteral booster immunization with the adsorbed DTxd vaccine. Time course study showed that high levels of toxin-neutralizing antibodies persisted for at least 14 weeks after the transcutaneous boost. In addition, TCI resulted in a vigorous antigen-specific proliferative response in all groups of mice boosted with the CRM(197) protein. These findings highlight the promising prospect of using booster administrations of CRM(197) via the transcutaneous route to establish good herd immunity against diphtheria.

Design and Implementation of nine level multilevel Inverter

NASA Astrophysics Data System (ADS)

Dhineshkumar, K.; Subramani, C.

2018-04-01

In this paper the solar based boost converter integrated Nine level multilevel inverter presented. It uses 7 switches to produce nine level output stepped waveform. The aim of the work to produce 9 level wave form using solar and boost converter. The conventional inverter has multiple sources and has 16 switches are required and also more number of voltage sources required. The proposed inverter required single solar panel and reduced number of switches and integrated boost converter which increase the input voltage of the inverter. The proposed inverter simulated and compared with R load using Mat lab and prototype model experimentally verified. The proposed inverter can be used in n number of solar applications.

Residence time, chemical and isotopic analysis of nitrate in the groundwater and surface water of a small agricultural watershed in the Coastal Plain, Bucks Branch, Sussex County, Delaware

USGS Publications Warehouse

Clune, John W.; Denver, Judith M.

2012-01-01

Nitrate is a common contaminant in groundwater and surface water throughout the Nation, and water-resource managers need more detailed small-scale watershed research to guide conservation efforts aimed at improving water quality. Concentrations of nitrate in Bucks Branch are among the highest in the state of Delaware and a scientific investigation was performed to provide water-quality information to assist with the management of agriculture and water resources. A combination of major-ion chemistry, nitrogen isotopic composition and age-dating techniques was used to estimate the residence time and provide a chemical and isotopic analysis of nitrate in the groundwater in the surficial aquifer of the Bucks Branch watershed in Sussex County, Delaware. The land use was more than 90 percent agricultural and most nitrogen inputs were from manure and fertilizer. The apparent median age of sampled groundwater is 18 years and the estimated residence time of groundwater contributing to the streamflow for the entire Bucks Branch watershed at the outlet is approximately 19 years. Concentrations of nitrate exceeded the U.S. Environmental Protection Agency drinking-water standard of 10 milligrams per liter (as nitrogen) in 60 percent of groundwater samples and 42 percent of surface-water samples. The overall geochemistry in the Bucks Branch watershed indicates that agriculture is the predominant source of nitrate contamination and the observed patterns in major-ion chemistry are similar to those observed in other studies on the Mid-Atlantic Coastal Plain. The pattern of enrichment in nitrogen and oxygen isotopes (δ15N and δ18O) of nitrate in groundwater and surface water indicates there is some loss of nitrate through denitrification, but this process is not sufficient to remove all of the nitrate from groundwater discharging to streams, and concentrations of nitrate in streams remain elevated.

HIV-1 gp120 and Modified Vaccinia Virus Ankara (MVA) gp140 Boost Immunogens Increase Immunogenicity of a DNA/MVA HIV-1 Vaccine.

PubMed

Shen, Xiaoying; Basu, Rahul; Sawant, Sheetal; Beaumont, David; Kwa, Sue Fen; LaBranche, Celia; Seaton, Kelly E; Yates, Nicole L; Montefiori, David C; Ferrari, Guido; Wyatt, Linda S; Moss, Bernard; Alam, S Munir; Haynes, Barton F; Tomaras, Georgia D; Robinson, Harriet L

2017-12-15

An important goal of human immunodeficiency virus (HIV) vaccine design is identification of strategies that elicit effective antiviral humoral immunity. One novel approach comprises priming with DNA and boosting with modified vaccinia virus Ankara (MVA) expressing HIV-1 Env on virus-like particles. In this study, we evaluated whether the addition of a gp120 protein in alum or MVA-expressed secreted gp140 (MVAgp140) could improve immunogenicity of a DNA prime-MVA boost vaccine. Five rhesus macaques per group received two DNA primes at weeks 0 and 8 followed by three MVA boosts (with or without additional protein or MVAgp140) at weeks 18, 26, and 40. Both boost immunogens enhanced the breadth of HIV-1 gp120 and V1V2 responses, antibody-dependent cellular cytotoxicity (ADCC), and low-titer tier 1B and tier 2 neutralizing antibody responses. However, there were differences in antibody kinetics, linear epitope specificity, and CD4 T cell responses between the groups. The gp120 protein boost elicited earlier and higher peak responses, whereas the MVAgp140 boost resulted in improved antibody durability and comparable peak responses after the final immunization. Linear V3 specific IgG responses were particularly enhanced by the gp120 boost, whereas the MVAgp140 boost also enhanced responses to linear C5 and C2.2 epitopes. Interestingly, gp120, but not the MVAgp140 boost, increased peak CD4 + T cell responses. Thus, both gp120 and MVAgp140 can augment potential protection of a DNA/MVA vaccine by enhancing gp120 and V1/V2 antibody responses, whereas potential protection by gp120, but not MVAgp140 boosts, may be further impacted by increased CD4 + T cell responses. IMPORTANCE Prior immune correlate analyses with humans and nonhuman primates revealed the importance of antibody responses in preventing HIV-1 infection. A DNA prime-modified vaccinia virus Ankara (MVA) boost vaccine has proven to be potent in eliciting antibody responses. Here we explore the ability of boosts with recombinant gp120 protein or MVA-expressed gp140 to enhance antibody responses elicited by the GOVX-B11 DNA prime-MVA boost vaccine. We found that both types of immunogen boosts enhanced potentially protective antibody responses, whereas the gp120 protein boosts also increased CD4 + T cell responses. Our data provide important information for HIV vaccine designs that aim for effective and balanced humoral and T cell responses. Copyright © 2017 Shen et al.

Informational model verification of ZVS Buck quasi-resonant DC-DC converter

NASA Astrophysics Data System (ADS)

Vakovsky, Dimiter; Hinov, Nikolay

2016-12-01

The aim of the paper is to create a polymorphic informational model of a ZVS Buck quasi-resonant DC-DC converter for the modeling purposes of the object. For the creation of the model is applied flexible open standards for setting, storing, publishing and exchange of data in distributed information environment. The created model is useful for creation of many and different by type variants with different configuration of the composing elements and different inner model of the examined object.

Flood Plain Information, Mill, Watson, and Lahaska Creeks, Bucks County, Pennsylvania.

DTIC Science & Technology

1975-05-01

AD-AIOI 592 ARENGINEER DISTRICT PHI LADELPHIA P A F/6 8/8 T7LOOD PLAIN INFORMATION, MIL , WATSON, AND LAI4ASKA CREEKS, SUCK-’ETCIU) UNCLASSIFIED...will be iu LblckW V’ A PREPARED FOR THE BUCKS COUNTY PLANNING COMMISSION p BY CORPS OF ENGINEERS, U.S. ARMY PHILADELPHIA DISTRICT MAY 975 8 1 7 20 055...No. 4655 at Langhorne , Pennsylvania) ..... ................. 8 3 Peak Flows for the Intermediate Regional and Standard Project Floods

Proceedings of the SERDP Coral Reef Monitoring and Assessment Workshop

DTIC Science & Technology

2009-12-01

the U.S. that have coral reefs within their jurisdictions. Biscayne National Park, the Dry Tortugas , and U.S. Virgin Island parks at St. John and...Signs Monitoring Networks Dry Tortugas NP Buck Island Reef NM Virgin Islands National Park Biscayne NP South Florida/Caribbean Network Florida/Caribbean...Buck Island, Dry Tortugas and Biscayne • Extensive sites – 4 10m permanent transects per site – 18 sites in DRTO Virgin Islands NP % l i v e c o r

Modeling, control, and simulation of battery storage photovoltaic-wave energy hybrid renewable power generation systems for island electrification in Malaysia.

PubMed

Samrat, Nahidul Hoque; Bin Ahmad, Norhafizan; Choudhury, Imtiaz Ahmed; Bin Taha, Zahari

2014-01-01

Today, the whole world faces a great challenge to overcome the environmental problems related to global energy production. Most of the islands throughout the world depend on fossil fuel importation with respect to energy production. Recent development and research on green energy sources can assure sustainable power supply for the islands. But unpredictable nature and high dependency on weather conditions are the main limitations of renewable energy sources. To overcome this drawback, different renewable sources and converters need to be integrated with each other. This paper proposes a standalone hybrid photovoltaic- (PV-) wave energy conversion system with energy storage. In the proposed hybrid system, control of the bidirectional buck-boost DC-DC converter (BBDC) is used to maintain the constant dc-link voltage. It also accumulates the excess hybrid power in the battery bank and supplies this power to the system load during the shortage of hybrid power. A three-phase complex vector control scheme voltage source inverter (VSI) is used to control the load side voltage in terms of the frequency and voltage amplitude. Based on the simulation results obtained from Matlab/Simulink, it has been found that the overall hybrid framework is capable of working under the variable weather and load conditions.

Modeling, Control, and Simulation of Battery Storage Photovoltaic-Wave Energy Hybrid Renewable Power Generation Systems for Island Electrification in Malaysia

PubMed Central

Samrat, Nahidul Hoque; Ahmad, Norhafizan Bin; Choudhury, Imtiaz Ahmed; Taha, Zahari Bin

2014-01-01

Today, the whole world faces a great challenge to overcome the environmental problems related to global energy production. Most of the islands throughout the world depend on fossil fuel importation with respect to energy production. Recent development and research on green energy sources can assure sustainable power supply for the islands. But unpredictable nature and high dependency on weather conditions are the main limitations of renewable energy sources. To overcome this drawback, different renewable sources and converters need to be integrated with each other. This paper proposes a standalone hybrid photovoltaic- (PV-) wave energy conversion system with energy storage. In the proposed hybrid system, control of the bidirectional buck-boost DC-DC converter (BBDC) is used to maintain the constant dc-link voltage. It also accumulates the excess hybrid power in the battery bank and supplies this power to the system load during the shortage of hybrid power. A three-phase complex vector control scheme voltage source inverter (VSI) is used to control the load side voltage in terms of the frequency and voltage amplitude. Based on the simulation results obtained from Matlab/Simulink, it has been found that the overall hybrid framework is capable of working under the variable weather and load conditions. PMID:24892049

A Study on Electric Power Smoothing System for Lead-Acid Battery of Stand-Alone Natural Energy Power System Using EDLC

NASA Astrophysics Data System (ADS)

Jia, Yan; Shibata, Ryosuke; Yamamura, Naoki; Ishida, Muneaki

To resolve energy shortage and global warming problem, renewable natural resource and its power system has been gradually generalizing. However, the power fluctuation suppressing in short period and the balance control of consumption and supply in long period are two of main problems that need to be resolved urgently in natural energy power system. In Stand-alone Natural Energy Power System (SNEPS) with power energy storage devices, power fluctuation in short period is one of the main reasons that recharge cycle times increase and lead-acid battery early failure. Hence, to prolong the service life of lead-acid battery and improve power quality through suppressing the power fluctuation, we proposed a method of electric power smoothing for lead-acid battery of SNEPS using bi-directional Buck/Boost converter and Electric Double Layer Capacitor (EDLC) in this paper. According to the test data of existing SNEPS, a power fluctuation condition is selected and as an example to analyze the validity of the proposed method. The analysis of frequency characteristics indicates the power fluctuation is suppressed a desired range in the target frequency region. The experimental results of confirmed the feasibility of the proposed system and the results well satisfy the requirement of system design.

Study of Piezoelectric Vibration Energy Harvester with non-linear conditioning circuit using an integrated model

NASA Astrophysics Data System (ADS)

Manzoor, Ali; Rafique, Sajid; Usman Iftikhar, Muhammad; Mahmood Ul Hassan, Khalid; Nasir, Ali

2017-08-01

Piezoelectric vibration energy harvester (PVEH) consists of a cantilever bimorph with piezoelectric layers pasted on its top and bottom, which can harvest power from vibrations and feed to low power wireless sensor nodes through some power conditioning circuit. In this paper, a non-linear conditioning circuit, consisting of a full-bridge rectifier followed by a buck-boost converter, is employed to investigate the issues of electrical side of the energy harvesting system. An integrated mathematical model of complete electromechanical system has been developed. Previously, researchers have studied PVEH with sophisticated piezo-beam models but employed simplistic linear circuits, such as resistor, as electrical load. In contrast, other researchers have worked on more complex non-linear circuits but with over-simplified piezo-beam models. Such models neglect different aspects of the system which result from complex interactions of its electrical and mechanical subsystems. In this work, authors have integrated the distributed parameter-based model of piezo-beam presented in literature with a real world non-linear electrical load. Then, the developed integrated model is employed to analyse the stability of complete energy harvesting system. This work provides a more realistic and useful electromechanical model having realistic non-linear electrical load unlike the simplistic linear circuit elements employed by many researchers.

Technical Study of a Standalone Photovoltaic–Wind Energy Based Hybrid Power Supply Systems for Island Electrification in Malaysia

PubMed Central

Samrat, Nahidul Hoque; Ahmad, Norhafizan; Choudhury, Imtiaz Ahmed; Taha, Zahari

2015-01-01

Energy is one of the most important factors in the socioeconomic development of a country. In a developing country like Malaysia, the development of islands is mostly related to the availability of electric power. Power generated by renewable energy sources has recently become one of the most promising solutions for the electrification of islands and remote rural areas. But high dependency on weather conditions and the unpredictable nature of these renewable energy sources are the main drawbacks. To overcome this weakness, different green energy sources and power electronic converters need to be integrated with each other. This study presents a battery storage hybrid standalone photovoltaic-wind energy power supply system. In the proposed standalone hybrid system, a DC-DC buck-boost bidirectional converter controller is used to accumulates the surplus hybrid power in the battery bank and supplies this power to the load during the hybrid power shortage by maintaining the constant dc-link voltage. A three-phase voltage source inverter complex vector control scheme is used to control the load side voltage in terms of the voltage amplitude and frequency. Based on the simulation results obtained from MATLAB/Simulink, it has been found that the overall hybrid framework is capable of working under variable weather and load conditions. PMID:26121032

Technical Study of a Standalone Photovoltaic-Wind Energy Based Hybrid Power Supply Systems for Island Electrification in Malaysia.

PubMed

Samrat, Nahidul Hoque; Ahmad, Norhafizan; Choudhury, Imtiaz Ahmed; Taha, Zahari

2015-01-01

Energy is one of the most important factors in the socioeconomic development of a country. In a developing country like Malaysia, the development of islands is mostly related to the availability of electric power. Power generated by renewable energy sources has recently become one of the most promising solutions for the electrification of islands and remote rural areas. But high dependency on weather conditions and the unpredictable nature of these renewable energy sources are the main drawbacks. To overcome this weakness, different green energy sources and power electronic converters need to be integrated with each other. This study presents a battery storage hybrid standalone photovoltaic-wind energy power supply system. In the proposed standalone hybrid system, a DC-DC buck-boost bidirectional converter controller is used to accumulates the surplus hybrid power in the battery bank and supplies this power to the load during the hybrid power shortage by maintaining the constant dc-link voltage. A three-phase voltage source inverter complex vector control scheme is used to control the load side voltage in terms of the voltage amplitude and frequency. Based on the simulation results obtained from MATLAB/Simulink, it has been found that the overall hybrid framework is capable of working under variable weather and load conditions.

Design and performance studies of a hadronic calorimeter for a FCC-hh experiment

NASA Astrophysics Data System (ADS)

Faltova, J.

2018-03-01

The hadron-hadron Future Circular Collider (FCC-hh) project studies the physics reach of a proton-proton machine with a centre-of-mass-energy of 100 TeV and five times greater peak luminosities than at the High-Luminosity LHC (HL-LHC). The high-energy regime of the FCC-hh opens new opportunities for the discovery of physics beyond the standard model. At 100 TeV a large fraction of the W, Z, H bosons and top quarks are produced with a significant boost. It implies an efficient reconstruction of very high energetic objects decaying hadronically. The reconstruction of those boosted objects sets the calorimeter performance requirements in terms of energy resolution, containment of highly energetic hadron showers, and high transverse granularity. We present the current baseline technologies for the calorimeter system in the barrel region of the FCC-hh reference detector: a liquid argon electromagnetic and a scintillator-steel hadronic calorimeters. The focus of this paper is on the hadronic calorimeter and the performance studies for hadrons. The reconstruction of single particles and the achieved energy resolution for the combined system of the electromagnetic and hadronic calorimeters are discussed.

Development and Testing of an Ultra Low Power System-On-Chip (SOC) Platform for Marine Mammal Tags and Passive Acoustic Signal Processing

DTIC Science & Technology

2014-09-30

current (3-5mA). The system can harvest 16 power from a DC input source like a thermoelectric generator (TEG) or photovoltaic cell (PV). The boost...results from components to report. Designed for thermoelectric energy harvesting in 130nm CMOS, the boost converter reduces the achievable input...harvesting. The boost converter further incorporates maximum power point tracking for harvesting from both thermoelectric generators (TEGs) and solar

Early boost and slow consolidation in motor skill learning.

PubMed

Hotermans, Christophe; Peigneux, Philippe; Maertens de Noordhout, Alain; Moonen, Gustave; Maquet, Pierre

2006-01-01

Motorskill learning is a dynamic process that continues covertly after training has ended and eventually leads to delayed increments in performance. Current theories suggest that this off-line improvement takes time and appears only after several hours. Here we show an early transient and short-lived boost in performance, emerging as early as 5-30 min after training but no longer observed 4 h later. This early boost is predictive of the performance achieved 48 h later, suggesting its functional relevance for memory processes.

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

Su, M; Sura, S

Purpose: To evaluate dosimetric impact of two axillary nodes (AX) boost techniques: (1) posterior-oblique optimized field boost (POB), (2) traditional posterior-anterior boost (PAB) with field optimization (O-PAB), for a postmastectomy breast patient with positive axillary lymph nodes. Methods: Five patients, 3 left and 2 right chest walls, were included in this study. All patients were simulated in 5mm CT slice thickness. Supraclavicular (SC) and level I/II/III AX were contoured based on the RTOG atlas guideline. Five treatment plans, (1) tangential chest wall, (2) oblique SC including AX, (3) PAB, O-PAB and POB, were created for each patient. Three plan sumsmore » (PS) were generated by sum one of (3) plan with plan (1) and (2). The field optimization was done through PS dose distribution, which included a field adjustment, a fractional dose, a calculation location and a gantry angle selection for POB. A dosimetric impact was evaluated by comparing a SC and AX coverage, a PS maximum dose, an irradiated area percentage volume received dose over 105% prescription dose (V105), an ipsi-laterial mean lung dose (MLD), an ipsi-laterial mean humeral head dose (MHHD), a mean heart dose (MHD) (for left case only) and their DVH amount these three technique. Results: O-PAB, POB and PAB dosimetric results showed that there was no significant different on SC and AX coverage (p>0.43) and MHD (p>0.16). The benefit of sparing lung irradiation from PAB to O-PAB to POB was significant (p<0.004). PAB showed a highest PS maximum dose (p<0.005), V105 (p<0.023) and MLD (compared with OPAB, p=0.055). MHHD showed very sensitive to the patient arm positioning and anatomy. O-PAB convinced a lower MHHD than PAB (p=0.03). Conclusion: 3D CT contouring plays main role in accuracy radiotherapy. Dosimetric advantage of POB and O-PAB was observed for a better normal tissue irradiation sparing.« less

The use of virtual reality and physical tools in the development and validation of ease of entry and exit in passenger vehicles.

PubMed

Lawson, Glyn; Herriotts, Paul; Malcolm, Louise; Gabrecht, Katharina; Hermawati, Setia

2015-05-01

Ease of entry and exit is important for creating a positive first impression of a car and increasing customer satisfaction. Several methods are used within vehicle development to optimise ease of entry and exit, including CAD reviews, benchmarking and buck trials. However, there is an industry trend towards digital methods to reduce the costs and time associated with developing physical prototypes. This paper reports on a study of entry strategy in three properties (buck, car, CAVE) in which inconsistencies were demonstrated by people entering a vehicle representation in the CAVE. In a second study industry practitioners rated the CAVE as worse than physical methods for identifying entry and exit issues, and having lower perceived validity and reliability. However, the resource issues associated with building bucks were recognised. Recommendations are made for developing the CAVE and for combinations of methods for use at different stages of a vehicle's development. Copyright © 2015 Elsevier Ltd and The Ergonomics Society. All rights reserved.

CYP3A induction and inhibition by different antiretroviral regimens reflected by changes in plasma 4beta-hydroxycholesterol levels.

PubMed

Josephson, F; Bertilsson, L; Böttiger, Y; Flamholc, L; Gisslén, M; Ormaasen, V; Sönnerborg, A; Diczfalusy, U

2008-08-01

A member of the major human cytochrome P450 superfamily of hemoproteins, CYP3A4/5, converts cholesterol into 4beta-hydroxycholesterol. We studied plasma 4beta-hydroxycholesterol levels prior to and 4 weeks after initiating antiretroviral therapy that included efavirenz, ritonavir-boosted atazanavir or ritonavir-boosted lopinavir with the aim of exploring the usefulness of plasma 4beta-hydroxycholesterol levels as an endogenous biomarker of CYP3A activity. Efavirenz is an inducer of CYP3A, whereas the ritonavir-boosted regimens are net inhibitors of CYP3A. In patients treated with efavirenz, the median plasma 4beta-hydroxycholesterol level increased by 46 ng/mL (p = 0.004; n = 11). In contrast, patients given ritonavir-boosted atazanavir showed a median decrease in plasma 4beta-hydroxycholesterol of -9.4 ng/mL (p = 0.0003; n = 22), and those given ritonavir-boosted lopinavir showed a median change from baseline of -5.8 ng/mL (p = 0.38; n = 19). There were significant between-group differences in the effects of antiretroviral treatment on plasma 4beta-hydroxycholesterol levels (p < 0.0001). Changes in plasma 4beta-hydroxycholesterol following the initiation of efavirenz- or atazanavir/ritonavir-based antiretroviral therapy reflected the respective net increase and decrease of CYP3A activity of these regimens. The plasma 4beta-hydroxycholesterol level did not indicate a net CYP3A inhibition in the lopinavir/ritonavir arm, possibly because of concomitant enzyme induction.

Explaining Charter School Effectiveness. NBER Working Paper No. 17332

ERIC Educational Resources Information Center

Angrist, Joshua D.; Pathak, Parag A.; Walters, Christopher R.

2011-01-01

Estimates using admissions lotteries suggest that urban charter schools boost student achievement, while charter schools in other settings do not. We explore student-level and school-level explanations for these differences using a large sample of Massachusetts charter schools. Our results show that urban charter schools boost achievement well…

Efficacy and safety of switching to fixed-dose bictegravir, emtricitabine, and tenofovir alafenamide from boosted protease inhibitor-based regimens in virologically suppressed adults with HIV-1: 48 week results of a randomised, open-label, multicentre, phase 3, non-inferiority trial.

PubMed

Daar, Eric S; DeJesus, Edwin; Ruane, Peter; Crofoot, Gordon; Oguchi, Godson; Creticos, Catherine; Rockstroh, Jürgen K; Molina, Jean-Michel; Koenig, Ellen; Liu, Ya-Pei; Custodio, Joseph; Andreatta, Kristen; Graham, Hiba; Cheng, Andrew; Martin, Hal; Quirk, Erin

2018-06-15

Switching from therapy based on a boosted protease inhibitor to bictegravir, emtricitabine, and tenofovir alafenamide could avoid drug interactions and unwanted side-effects in virologically suppressed adults with HIV-1 infection, while maintaining a high barrier to resistance and providing a simplified once-daily, single-tablet regimen. Here, we report 48 week results of a phase 3 study investigating this switch. In this multicentre, randomised, open-label, active-controlled, non-inferiority, phase 3 trial, adults with HIV-1 infection were enrolled at 121 outpatient centres in ten countries. Eligible participants were aged 18 years or older, had an estimated glomerular filtration rate of 50 mL per min or higher, had been virologically suppressed (plasma HIV-1 RNA <50 copies per mL) for 6 months or more before screening, and were on a regimen consisting of boosted atazanavir or darunavir plus either emtricitabine and tenofovir disoproxil fumarate or abacavir and lamivudine. We randomly assigned participants (1:1), using a computer-generated randomisation sequence, to switch to co-formulated once-daily bictegravir (50 mg), emtricitabine (200 mg), and tenofovir alafenamide (25 mg), herein known as the bictegravir group, or to remain on their baseline boosted protease inhibitor regimen, herein known as the boosted protease inhibitor group, for 48 weeks. Randomisation was stratified by use of tenofovir disoproxil fumarate or abacavir at screening. The primary endpoint was the proportion of participants with plasma HIV-1 RNA of 50 copies per mL or higher at week 48 (by US Food and Drug Administration snapshot algorithm), with a prespecified non-inferiority margin of 4%. Efficacy and safety analyses included all participants who received at least one dose of study drug. This study is ongoing but not actively recruiting patients and is registered with ClinicalTrials.gov, number NCT02603107. Between Dec 2, 2015, and July 15, 2016, 578 participants were randomly assigned and 577 were treated (290 in the bictegravir group and 287 in the boosted protease inhibitor group). At week 48, five participants (2%) in the bictegravir group and five (2%) in the boosted protease inhibitor group had plasma HIV-1 RNA of 50 copies per mL or higher (difference 0·0%, 95·002% CI -2·5 to 2·5), thus switching to the bictegravir regimen was non-inferior to continued boosted protease inhibitor therapy. The overall incidence and severity of adverse events was similar between groups, although headache occurred more frequently in the bictegravir group than in the boosted protease inhibitor group. 233 (80%) participants in the bictegravir group and 226 (79%) in the boosted protease inhibitor group had an adverse event. Only two (1%) participants in the bictegravir group and one (<1%) in the boosted protease inhibitor group discontinued treatment because of adverse events. 54 participants (19%) in the bictegravir group had drug-related adverse events compared with six (2%) in the protease inhibitor group. Fixed-dose bictegravir, emtricitabine, and tenofovir alafenamide might be a safe and efficacious alternative to continued boosted protease inhibitor therapy in adults with HIV-1 infection. Gilead Sciences. Copyright © 2018 Elsevier Ltd. All rights reserved.

A comparison of the techniques of direct pars interarticularis repairs for spondylolysis and low-grade spondylolisthesis: a meta-analysis.

PubMed

Mohammed, Nasser; Patra, Devi Prasad; Narayan, Vinayak; Savardekar, Amey R; Dossani, Rimal Hanif; Bollam, Papireddy; Bir, Shyamal; Nanda, Anil

2018-01-01

OBJECTIVE Spondylosis with or without spondylolisthesis that does not respond to conservative management has an excellent outcome with direct pars interarticularis repair. Direct repair preserves the segmental spinal motion. A number of operative techniques for direct repair are practiced; however, the procedure of choice is not clearly defined. The present study aims to clarify the advantages and disadvantages of the different operative techniques and their outcomes. METHODS A meta-analysis was conducted in accordance with the PRISMA (Preferred Reporting Items for Systematic Reviews and Meta-Analyses) guidelines. The following databases were searched: PubMed, Cochrane Library, Web of Science, and CINAHL ( Cumulative Index to Nursing and Allied Health Literature). Studies of patients with spondylolysis with or without low-grade spondylolisthesis who underwent direct repair were included. The patients were divided into 4 groups based on the operative technique used: the Buck repair group, Scott repair group, Morscher repair group, and pedicle screw-based repair group. The pooled data were analyzed using the DerSimonian and Laird random-effects model. Tests for bias and heterogeneity were performed. The I 2 statistic was calculated, and the results were analyzed. Statistical analysis was performed using StatsDirect version 2. RESULTS Forty-six studies consisting of 900 patients were included in the study. The majority of the patients were in their 2nd decade of life. The Buck group included 19 studies with 305 patients; the Scott group had 8 studies with 162 patients. The Morscher method included 5 studies with 193 patients, and the pedicle group included 14 studies with 240 patients. The overall pooled fusion, complication, and outcome rates were calculated. The pooled rates for fusion for the Buck, Scott, Morscher, and pedicle screw groups were 83.53%, 81.57%, 77.72%, and 90.21%, respectively. The pooled complication rates for the Buck, Scott, Morscher, and pedicle screw groups were 13.41%, 22.35%, 27.42%, and 12.8%, respectively, and the pooled positive outcome rates for the Buck, Scott, Morscher, and pedicle screw groups were 84.33%, 82.49%, 80.30%, and 80.1%, respectively. The pedicle group had the best fusion rate and lowest complication rate. CONCLUSIONS The pedicle screw-based direct pars repair for spondylolysis and low-grade spondylolisthesis is the best choice of procedure, with the highest fusion and lowest complication rates, followed by the Buck repair. The Morscher and Scott repairs were associated with a high rate of complication and lower rates of fusion.

The isolation of females from males to promote a later male effect is unnecessary if the bucks used are sexually active.

PubMed

Zarazaga, L A; Gatica, M C; Hernández, H; Gallego-Calvo, L; Delgadillo, J A; Guzmán, J L

2017-06-01

It has been suggested that female goats in permanent contact with males become refractory to their presence, and need to be previously separated from them for 40-45 days if the presence of bucks is to induce reproductive activity, ovulation and oestrous during seasonal anoestrous. The present study examines the reproductive response (ovulation and oestrus) and reproductive performance of does isolated from bucks for different periods before their reintroduction to male company. A total of 103 Payoya and Blanca Andaluza does were distributed into six treatment groups that required their isolation from males for different periods: 0 days (N = 29), 5 days (N = 15), 10 days (N = 14), 20 days (N = 16), 30 days (N = 14) and 39 days (N = 15). After this period they were introduced to sexually active bucks (ensured to be in this condition by keeping them under long days light treatment for three months), and oestrous activity was recorded daily by direct visual observation of the marks left by the marking harnesses worn by these males. Ovulation was confirmed via the plasma progesterone concentration (measured in blood samples taken twice per week). The ovulation rate was assessed by transrectal ultrasonography. Fecundity, fertility, prolificacy and productivity were also determined. The sexual behaviour of the males towards the females was also monitored on Days 0, 1, 2, 3, 4, 8 and 9 after their meeting with the latter. The length of the female isolation period had no effect on the percentage of does that responded to contact with the males, nor did it affect the oestrous response, fecundity, fertility or productivity. The males, however, undertook more ano-genital sniffing and nudging with the 5 day group females compared to those of the other groups (P < 0.05). However, the sexual behaviour of the males changed as the days passed, with ano-genital sniffing becoming less common, and nudging, licking, sneezing and mounts with intromission more frequent on Days 8 and 9 than on Day 0, 1 and 2 after the sexes were reunited (P < 0.05). These results show that the isolation of females is not necessary for an efficient male effect if the bucks used are sexually active. In addition, the sexual behaviour of the bucks changes as the time in contact with the does increases, but in general is not affected by the duration of female isolation. Copyright © 2017 Elsevier Inc. All rights reserved.

Four-Dimensional Positron Emission Tomography: Implications for Dose Painting of High-Uptake Regions

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

Aristophanous, Michalis, E-mail: maristophanous@lroc.harvard.edu; Yap, Jeffrey T.; Killoran, Joseph H.

Purpose: To investigate the behavior of tumor subvolumes of high [18F]-fluorodeoxyglucose (FDG) uptake as seen on clinical four-dimensional (4D) FDG-positron emission tomography (PET) scans. Methods and Materials: Four-dimensional FDG-PET/computed tomography scans from 13 patients taken before radiotherapy were available. The analysis was focused on regions of high uptake that are potential dose-painting targets. A total of 17 lesions (primary tumors and lymph nodes) were analyzed. On each one of the five phases of the 4D scan a classification algorithm was applied to obtain the region of highest uptake and segment the tumor volume. We looked at the behavior of bothmore » the high-uptake subvolume, called 'Boost,' and the segmented tumor volume, called 'Target.' We measured several quantities that characterize the Target and Boost volumes and quantified correlations between them. Results: The behavior of the Target could not always predict the behavior of the Boost. The shape deformation of the Boost regions was on average 133% higher than that of the Target. The gross to internal target volume expansion was on average 27.4% for the Target and 64% for the Boost, a statistically significant difference (p < 0.05). Finally, the inhale-to-exhale phase (20%) had the highest shape deformation for the Boost regions. Conclusions: A complex relationship between the measured quantities for the Boost and Target volumes is revealed. The results suggest that in cases in which advanced therapy techniques such as dose painting are being used, a close examination of the 4D PET scan should be performed.« less

Fast automatic 3D liver segmentation based on a three-level AdaBoost-guided active shape model.

PubMed

He, Baochun; Huang, Cheng; Sharp, Gregory; Zhou, Shoujun; Hu, Qingmao; Fang, Chihua; Fan, Yingfang; Jia, Fucang

2016-05-01

A robust, automatic, and rapid method for liver delineation is urgently needed for the diagnosis and treatment of liver disorders. Until now, the high variability in liver shape, local image artifacts, and the presence of tumors have complicated the development of automatic 3D liver segmentation. In this study, an automatic three-level AdaBoost-guided active shape model (ASM) is proposed for the segmentation of the liver based on enhanced computed tomography images in a robust and fast manner, with an emphasis on the detection of tumors. The AdaBoost voxel classifier and AdaBoost profile classifier were used to automatically guide three-level active shape modeling. In the first level of model initialization, fast automatic liver segmentation by an AdaBoost voxel classifier method is proposed. A shape model is then initialized by registration with the resulting rough segmentation. In the second level of active shape model fitting, a prior model based on the two-class AdaBoost profile classifier is proposed to identify the optimal surface. In the third level, a deformable simplex mesh with profile probability and curvature constraint as the external force is used to refine the shape fitting result. In total, three registration methods-3D similarity registration, probability atlas B-spline, and their proposed deformable closest point registration-are used to establish shape correspondence. The proposed method was evaluated using three public challenge datasets: 3Dircadb1, SLIVER07, and Visceral Anatomy3. The results showed that our approach performs with promising efficiency, with an average of 35 s, and accuracy, with an average Dice similarity coefficient (DSC) of 0.94 ± 0.02, 0.96 ± 0.01, and 0.94 ± 0.02 for the 3Dircadb1, SLIVER07, and Anatomy3 training datasets, respectively. The DSC of the SLIVER07 testing and Anatomy3 unseen testing datasets were 0.964 and 0.933, respectively. The proposed automatic approach achieves robust, accurate, and fast liver segmentation for 3D CTce datasets. The AdaBoost voxel classifier can detect liver area quickly without errors and provides sufficient liver shape information for model initialization. The AdaBoost profile classifier achieves sufficient accuracy and greatly decreases segmentation time. These results show that the proposed segmentation method achieves a level of accuracy comparable to that of state-of-the-art automatic methods based on ASM.

Accuracy in estimation of timber assortments and stem distribution - A comparison of airborne and terrestrial laser scanning techniques

NASA Astrophysics Data System (ADS)

Kankare, Ville; Vauhkonen, Jari; Tanhuanpää, Topi; Holopainen, Markus; Vastaranta, Mikko; Joensuu, Marianna; Krooks, Anssi; Hyyppä, Juha; Hyyppä, Hannu; Alho, Petteri; Viitala, Risto

2014-11-01

Detailed information about timber assortments and diameter distributions is required in forest management. Forest owners can make better decisions concerning the timing of timber sales and forest companies can utilize more detailed information to optimize their wood supply chain from forest to factory. The objective here was to compare the accuracies of high-density laser scanning techniques for the estimation of tree-level diameter distribution and timber assortments. We also introduce a method that utilizes a combination of airborne and terrestrial laser scanning in timber assortment estimation. The study was conducted in Evo, Finland. Harvester measurements were used as a reference for 144 trees within a single clear-cut stand. The results showed that accurate tree-level timber assortments and diameter distributions can be obtained, using terrestrial laser scanning (TLS) or a combination of TLS and airborne laser scanning (ALS). Saw log volumes were estimated with higher accuracy than pulpwood volumes. The saw log volumes were estimated with relative root-mean-squared errors of 17.5% and 16.8% with TLS and a combination of TLS and ALS, respectively. The respective accuracies for pulpwood were 60.1% and 59.3%. The differences in the bucking method used also caused some large errors. In addition, tree quality factors highly affected the bucking accuracy, especially with pulpwood volume.

Bucking coil implementation on PMT for active canceling of magnetic field

NASA Astrophysics Data System (ADS)

Gogami, T.; Asaturyan, A.; Bono, J.; Baturin, P.; Chen, C.; Chiba, A.; Chiga, N.; Fujii, Y.; Hashimoto, O.; Kawama, D.; Maruta, T.; Maxwell, V.; Mkrtchyan, A.; Nagao, S.; Nakamura, S. N.; Reinhold, J.; Shichijo, A.; Tang, L.; Taniya, N.; Wood, S. A.; Ye, Z.

2013-11-01

Aerogel and water Čherenkov detectors were employed to tag kaons for a Λ hypernuclear spectroscopic experiment which used the (e,e‧K+) reaction in experimental Hall C at Jefferson Lab (JLab E05-115). Fringe fields from the kaon spectrometer magnet yielded ~5 gauss at the photomultiplier tubes for these detectors. These fields, which could not be easily passively shielded, would result in a lowered kaon detection efficiency if not mitigated. A bucking coil was placed on each photomultiplier tube to actively cancel this magnetic field, thus recovering kaon detection efficiency.

Consideration of impedance matching techniques for efficient piezoelectric energy harvesting.

PubMed

Kim, Hyeoungwoo; Priya, Shashank; Stephanou, Harry; Uchino, Kenji

2007-09-01

This study investigates multiple levels of impedance-matching methods for piezoelectric energy harvesting in order to enhance the conversion of mechanical to electrical energy. First, the transduction rate was improved by using a high piezoelectric voltage constant (g) ceramic material having a magnitude of g33 = 40 x 10(-3) V m/N. Second, a transducer structure, cymbal, was optimized and fabricated to match the mechanical impedance of vibration source to that of the piezoelectric transducer. The cymbal transducer was found to exhibit approximately 40 times higher effective strain coefficient than the piezoelectric ceramics. Third, the electrical impedance matching for the energy harvesting circuit was considered to allow the transfer of generated power to a storage media. It was found that, by using the 10-layer ceramics instead of the single layer, the output current can be increased by 10 times, and the output load can be reduced by 40 times. Furthermore, by using the multilayer ceramics the output power was found to increase by 100%. A direct current (DC)-DC buck converter was fabricated to transfer the accumulated electrical energy in a capacitor to a lower output load. The converter was optimized such that it required less than 5 mW for operation.

Five-year Local Control in a Phase II Study of Hypofractionated Intensity Modulated Radiation Therapy With an Incorporated Boost for Early Stage Breast Cancer

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

Freedman, Gary M., E-mail: Gary.Freedman@uphs.upenn.edu; Anderson, Penny R.; Bleicher, Richard J.

Purpose: Conventional radiation fractionation of 1.8-2 Gy per day for early stage breast cancer requires daily treatment for 6-7 weeks. We report the 5-year results of a phase II study of intensity modulated radiation therapy (IMRT), hypofractionation, and incorporated boost that shortened treatment time to 4 weeks. Methods and Materials: The study design was phase II with a planned accrual of 75 patients. Eligibility included patients aged {>=}18 years, Tis-T2, stage 0-II, and breast conservation. Photon IMRT and an incorporated boost was used, and the whole breast received 2.25 Gy per fraction for a total of 45 Gy, and themore » tumor bed received 2.8 Gy per fraction for a total of 56 Gy in 20 treatments over 4 weeks. Patients were followed every 6 months for 5 years. Results: Seventy-five patients were treated from December 2003 to November 2005. The median follow-up was 69 months. Median age was 52 years (range, 31-81). Median tumor size was 1.4 cm (range, 0.1-3.5). Eighty percent of tumors were node negative; 93% of patients had negative margins, and 7% of patients had close (>0 and <2 mm) margins; 76% of cancers were invasive ductal type: 15% were ductal carcinoma in situ, 5% were lobular, and 4% were other histology types. Twenty-nine percent of patients 29% had grade 3 carcinoma, and 20% of patients had extensive in situ carcinoma; 11% of patients received chemotherapy, 36% received endocrine therapy, 33% received both, and 20% received neither. There were 3 instances of local recurrence for a 5-year actuarial rate of 2.7%. Conclusions: This 4-week course of hypofractionated radiation with incorporated boost was associated with excellent local control, comparable to historical results of 6-7 weeks of conventional whole-breast fractionation with sequential boost.« less

High-performance fractional order terminal sliding mode control strategy for DC-DC Buck converter

PubMed Central

Xu, Dan; Zhou, Huan; Bai, Anning; Lu, Wei

2017-01-01

This paper presents an adaption of the fractional order terminal sliding mode control (AFTSMC) strategy for DC-DC Buck converter. The following strategy aims to design a novel nonlinear sliding surface function, with a double closed-loop structure of voltage and current. This strategy is a fusion of two characteristics: terminal sliding mode control (TSMC) and fractional order calculation (FOC). In addition, the influence of “the controller parameters” on the “performance of double closed-loop system” is investigated. It is observed that the value of terminal power has to be chosen to make a compromise between start-up and transient response of the converter. Therefore the AFTSMC strategy chooses the value of the terminal power adaptively, and this strategy can lead to the appropriate number of fractional order as well. Furthermore, through the fractional order analysis, the system can reach the sliding mode surface in a finite time. And the theoretical considerations are verified by numerical simulation. The performance of the AFTSMC and TSMC strategies is tested by computer simulations. And the comparison simulation results show that the AFTSMC exhibits a considerable improvement in terms of a faster output voltage response during load changes. Moreover, AFTSMC obtains a faster dynamical response, smaller steady-state error rate and lower overshoot. PMID:29084255

High-performance fractional order terminal sliding mode control strategy for DC-DC Buck converter.

PubMed

Wang, Jianlin; Xu, Dan; Zhou, Huan; Bai, Anning; Lu, Wei

2017-01-01

This paper presents an adaption of the fractional order terminal sliding mode control (AFTSMC) strategy for DC-DC Buck converter. The following strategy aims to design a novel nonlinear sliding surface function, with a double closed-loop structure of voltage and current. This strategy is a fusion of two characteristics: terminal sliding mode control (TSMC) and fractional order calculation (FOC). In addition, the influence of "the controller parameters" on the "performance of double closed-loop system" is investigated. It is observed that the value of terminal power has to be chosen to make a compromise between start-up and transient response of the converter. Therefore the AFTSMC strategy chooses the value of the terminal power adaptively, and this strategy can lead to the appropriate number of fractional order as well. Furthermore, through the fractional order analysis, the system can reach the sliding mode surface in a finite time. And the theoretical considerations are verified by numerical simulation. The performance of the AFTSMC and TSMC strategies is tested by computer simulations. And the comparison simulation results show that the AFTSMC exhibits a considerable improvement in terms of a faster output voltage response during load changes. Moreover, AFTSMC obtains a faster dynamical response, smaller steady-state error rate and lower overshoot.

Characterizing interdisciplinarity of researchers and research topics using web search engines.

PubMed

Sayama, Hiroki; Akaishi, Jin

2012-01-01

Researchers' networks have been subject to active modeling and analysis. Earlier literature mostly focused on citation or co-authorship networks reconstructed from annotated scientific publication databases, which have several limitations. Recently, general-purpose web search engines have also been utilized to collect information about social networks. Here we reconstructed, using web search engines, a network representing the relatedness of researchers to their peers as well as to various research topics. Relatedness between researchers and research topics was characterized by visibility boost-increase of a researcher's visibility by focusing on a particular topic. It was observed that researchers who had high visibility boosts by the same research topic tended to be close to each other in their network. We calculated correlations between visibility boosts by research topics and researchers' interdisciplinarity at the individual level (diversity of topics related to the researcher) and at the social level (his/her centrality in the researchers' network). We found that visibility boosts by certain research topics were positively correlated with researchers' individual-level interdisciplinarity despite their negative correlations with the general popularity of researchers. It was also found that visibility boosts by network-related topics had positive correlations with researchers' social-level interdisciplinarity. Research topics' correlations with researchers' individual- and social-level interdisciplinarities were found to be nearly independent from each other. These findings suggest that the notion of "interdisciplinarity" of a researcher should be understood as a multi-dimensional concept that should be evaluated using multiple assessment means.

Mucosal priming of newborn mice with S. Typhi Ty21a expressing anthrax protective antigen (PA) followed by parenteral PA-boost induces B and T cell-mediated immunity that protects against infection bypassing maternal antibodies

PubMed Central

Ramirez, Karina; Ditamo, Yanina; Galen, James E.; Baillie, Les W. J.; Pasetti, Marcela F.

2010-01-01

The currently licensed anthrax vaccine has several limitations and its efficacy has been proven only in adults. Effective immunization of newborns and infants requires adequate stimulation of their immune system, which is competent but not fully activated. We explored the use of the licensed live attenuated S. Typhi vaccine strain Ty21a expressing Bacillus anthracis protective antigen [Ty21a(PA)] followed PA-alum as a strategy for immunizing the pediatric population. Newborn mice primed with a single dose of Ty21a(PA) exhibited high frequencies of mucosal IgA-secreting B cells and IFN-γ-secreting T cells during the neonatal period, none of which was detected in newborns immunized with a single dose of PA-alum. Priming with Ty21a(PA) followed by PA-boost resulted in high levels of PA-specific IgG, toxin-neutralizing and opsonophagocytic antibodies and increased frequency of bone marrow IgG plasma cells and memory B cells compared with repeated immunization with PA-alum alone. Robust B and T cell responses developed even in the presence of maternal antibodies. The prime-boost protected against systemic and respiratory infection. Mucosal priming with a safe and effective S. Typhi-based anthrax vaccine followed by PA-boost could serve as a practical and effective prophylactic approach to prevent anthrax early in life. PMID:20619377

Early Boost and Slow Consolidation in Motor Skill Learning

ERIC Educational Resources Information Center

Hotermans, Christophe; Peigneux, Philippe; de Noordhout, Alain Maertens; Moonen, Gustave; Maquet, Pierre

2006-01-01

Motor skill learning is a dynamic process that continues covertly after training has ended and eventually leads to delayed increments in performance. Current theories suggest that this off-line improvement takes time and appears only after several hours. Here we show an early transient and short-lived boost in performance, emerging as early as…

A High Efficiency Boost Converter with MPPT Scheme for Low Voltage Thermoelectric Energy Harvesting

NASA Astrophysics Data System (ADS)

Guan, Mingjie; Wang, Kunpeng; Zhu, Qingyuan; Liao, Wei-Hsin

2016-11-01

Using thermoelectric elements to harvest energy from heat has been of great interest during the last decade. This paper presents a direct current-direct current (DC-DC) boost converter with a maximum power point tracking (MPPT) scheme for low input voltage thermoelectric energy harvesting applications. Zero current switch technique is applied in the proposed MPPT scheme. Theoretical analysis on the converter circuits is explored to derive the equations for parameters needed in the design of the boost converter. Simulations and experiments are carried out to verify the theoretical analysis and equations. A prototype of the designed converter is built using discrete components and a low-power microcontroller. The results show that the designed converter can achieve a high efficiency at low input voltage. The experimental efficiency of the designed converter is compared with a commercial converter solution. It is shown that the designed converter has a higher efficiency than the commercial solution in the considered voltage range.

Improving medical diagnosis reliability using Boosted C5.0 decision tree empowered by Particle Swarm Optimization.

PubMed

Pashaei, Elnaz; Ozen, Mustafa; Aydin, Nizamettin

2015-08-01

Improving accuracy of supervised classification algorithms in biomedical applications is one of active area of research. In this study, we improve the performance of Particle Swarm Optimization (PSO) combined with C4.5 decision tree (PSO+C4.5) classifier by applying Boosted C5.0 decision tree as the fitness function. To evaluate the effectiveness of our proposed method, it is implemented on 1 microarray dataset and 5 different medical data sets obtained from UCI machine learning databases. Moreover, the results of PSO + Boosted C5.0 implementation are compared to eight well-known benchmark classification methods (PSO+C4.5, support vector machine under the kernel of Radial Basis Function, Classification And Regression Tree (CART), C4.5 decision tree, C5.0 decision tree, Boosted C5.0 decision tree, Naive Bayes and Weighted K-Nearest neighbor). Repeated five-fold cross-validation method was used to justify the performance of classifiers. Experimental results show that our proposed method not only improve the performance of PSO+C4.5 but also obtains higher classification accuracy compared to the other classification methods.

Design and analysis of an unconventional permanent magnet linear machine for energy harvesting

NASA Astrophysics Data System (ADS)

Zeng, Peng

This Ph.D. dissertation proposes an unconventional high power density linear electromagnetic kinetic energy harvester, and a high-performance two-stage interface power electronics to maintain maximum power abstraction from the energy source and charge the Li-ion battery load with constant current. The proposed machine architecture is composed of a double-sided flat type silicon steel stator with winding slots, a permanent magnet mover, coil windings, a linear motion guide and an adjustable spring bearing. The unconventional design of the machine is that NdFeB magnet bars in the mover are placed with magnetic fields in horizontal direction instead of vertical direction and the same magnetic poles are facing each other. The derived magnetic equivalent circuit model proves the average air-gap flux density of the novel topology is as high as 0.73 T with 17.7% improvement over that of the conventional topology at the given geometric dimensions of the proof-of-concept machine. Subsequently, the improved output voltage and power are achieved. The dynamic model of the linear generator is also developed, and the analytical equations of output maximum power are derived for the case of driving vibration with amplitude that is equal, smaller and larger than the relative displacement between the mover and the stator of the machine respectively. Furthermore, the finite element analysis (FEA) model has been simulated to prove the derived analytical results and the improved power generation capability. Also, an optimization framework is explored to extend to the multi-Degree-of-Freedom (n-DOF) vibration based linear energy harvesting devices. Moreover, a boost-buck cascaded switch mode converter with current controller is designed to extract the maximum power from the harvester and charge the Li-ion battery with trickle current. Meanwhile, a maximum power point tracking (MPPT) algorithm is proposed and optimized for low frequency driving vibrations. Finally, a proof-of-concept unconventional permanent magnet (PM) linear generator is prototyped and tested to verify the simulation results of the FEA model. For the coil windings of 33, 66 and 165 turns, the output power of the machine is tested to have the output power of 65.6 mW, 189.1 mW, and 497.7 mW respectively with the maximum power density of 2.486 mW/cm3.

Evaluation of biofidelity of THUMS pedestrian model under a whole-body impact conditions with a generic sedan buck.

PubMed

Wu, Taotao; Kim, Taewung; Bollapragada, Varun; Poulard, David; Chen, Huipeng; Panzer, Matthew B; Forman, Jason L; Crandall, Jeff R; Pipkorn, Bengt

2017-05-29

The goal of this study was to evaluate the biofidelity of the Total Human Model for Safety (THUMS; Ver. 4.01) pedestrian finite element models (PFEM) in a whole-body pedestrian impact condition using a well-characterized generic pedestrian buck model. The biofidelity of THUMS PFEM was evaluated with respect to data from 3 full-scale postmortem human subject (PMHS) pedestrian impact tests, in which a pedestrian buck laterally struck the subjects using a pedestrian buck at 40 km/h. The pedestrian model was scaled to match the anthropometry of the target subjects and then positioned to match the pre-impact postures of the target subjects based on the 3-dimensional motion tracking data obtained during the experiments. An objective rating method was employed to quantitatively evaluate the correlation between the responses of the models and the PMHS. Injuries in the models were predicted both probabilistically and deterministically using empirical injury risk functions and strain measures, respectively, and compared with those of the target PMHS. In general, the model exhibited biofidelic kinematic responses (in the Y-Z plane) regarding trajectories (International Organization for Standardization [ISO] ratings: Y = 0.90 ± 0.11, Z = 0.89 ± 0.09), linear resultant velocities (ISO ratings: 0.83 ± 0.07), accelerations (ISO ratings: Y = 0.58 ± 0.11, Z = 0.52 ± 0.12), and angular velocities (ISO ratings: X = 0.48 ± 0.13) but exhibited stiffer leg responses and delayed head responses compared to those of the PMHS. This indicates potential biofidelity issues with the PFEM for regions below the knee and in the neck. The model also demonstrated comparable reaction forces at the buck front-end regions to those from the PMHS tests. The PFEM generally predicted the injuries that the PMHS sustained but overestimated injuries in the ankle and leg regions. Based on the data considered, the THUMS PFEM was considered to be biofidelic for this pedestrian impact condition and vehicle. Given the capability of the model to reproduce biomechanical responses, it shows potential as a valuable tool for developing novel pedestrian safety systems.

Fast automatic 3D liver segmentation based on a three-level AdaBoost-guided active shape model

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

He, Baochun; Huang, Cheng; Zhou, Shoujun

Purpose: A robust, automatic, and rapid method for liver delineation is urgently needed for the diagnosis and treatment of liver disorders. Until now, the high variability in liver shape, local image artifacts, and the presence of tumors have complicated the development of automatic 3D liver segmentation. In this study, an automatic three-level AdaBoost-guided active shape model (ASM) is proposed for the segmentation of the liver based on enhanced computed tomography images in a robust and fast manner, with an emphasis on the detection of tumors. Methods: The AdaBoost voxel classifier and AdaBoost profile classifier were used to automatically guide three-levelmore » active shape modeling. In the first level of model initialization, fast automatic liver segmentation by an AdaBoost voxel classifier method is proposed. A shape model is then initialized by registration with the resulting rough segmentation. In the second level of active shape model fitting, a prior model based on the two-class AdaBoost profile classifier is proposed to identify the optimal surface. In the third level, a deformable simplex mesh with profile probability and curvature constraint as the external force is used to refine the shape fitting result. In total, three registration methods—3D similarity registration, probability atlas B-spline, and their proposed deformable closest point registration—are used to establish shape correspondence. Results: The proposed method was evaluated using three public challenge datasets: 3Dircadb1, SLIVER07, and Visceral Anatomy3. The results showed that our approach performs with promising efficiency, with an average of 35 s, and accuracy, with an average Dice similarity coefficient (DSC) of 0.94 ± 0.02, 0.96 ± 0.01, and 0.94 ± 0.02 for the 3Dircadb1, SLIVER07, and Anatomy3 training datasets, respectively. The DSC of the SLIVER07 testing and Anatomy3 unseen testing datasets were 0.964 and 0.933, respectively. Conclusions: The proposed automatic approach achieves robust, accurate, and fast liver segmentation for 3D CTce datasets. The AdaBoost voxel classifier can detect liver area quickly without errors and provides sufficient liver shape information for model initialization. The AdaBoost profile classifier achieves sufficient accuracy and greatly decreases segmentation time. These results show that the proposed segmentation method achieves a level of accuracy comparable to that of state-of-the-art automatic methods based on ASM.« less

Spermatogonial stem cells in the testis of an endangered bovid: Indian black buck (Antilope cervicapra L.).

PubMed

Goel, Sandeep; Reddy, Niranjan; Mahla, Ranjeet Singh; Suman, Sanjay Kumar; Pawar, Rahul Mohanchandra

2011-07-01

Numerous wild bovids are facing threat of extinction owing to the loss of habitat and various other reasons. Spermatogonial stem cells (SSCs) represent the only germline stem cells in adult body that are capable of self-renewal and that can undergo differentiation to produce haploid germ cells. SSCs can, therefore, serve as a useful resource for preservation of germplasm of threatened and endangered mammals. The Indian black buck (Antilope cervicapra L.) is a small Indian antelope that is listed as endangered by the Indian Wildlife Protection Act, 1972. Immunohistochemical analysis of testes tissues of black buck revealed the presence of spermatogonia that were specifically stained by lectin-Dolichos biflorus agglutinin (DBA). The expression of pluripotent cell-specific markers, NANOG and stage-specific embryonic antigen-1 (SSEA-1), was detected in spermatogonia. Interestingly, the expression of POU5F1 (OCT3/4) was absent from spermatogonia, however, it was detected in differentiating cells such as spermatocytes and round spermatids but not in elongated spermatids. The expression of NANOG protein was also present in spermatocytes but absent in round and elongated spermatids. Using the testis transplantation assay, stem cell potential of black buck spermatogonia was confirmed as indicated by the presence of colonized DBA-stained cells in the basal membrane of seminiferous tubules of xenotransplanted mice testis. The findings from this study suggest the presence of SSCs in the testis of an endangered bovid for the first time and open new possibility to explore the use of SSCs in conservation. Copyright © 2011 Elsevier B.V. All rights reserved.

A Comparison between Two Heterodyne Light Sources Using Different Electro-Optic Modulators for Optical Temperature Measurements at Visible Wavelengths

PubMed Central

Twu, Ruey-Ching; Lee, Yi-Huan; Hou, Hong-Yao

2010-01-01

In this paper we have successfully demonstrated a z-propagating Zn-indiffused lithium niobate electro-optic modulator used for optical heterodyne interferometry. Compared to a commercial buck-type electro-optic modulator, the proposed waveguide-type modulator has a lower driving voltage and smaller phase variation while measuring visible wavelengths of 532 nm and 632.8 nm. We also demonstrate an optical temperature measurement system using a homemade modulator. The results show that the measurement sensitivities are almost the same values of 25 deg/°C for both the homemade and the buck-type modulators for a sensing light with a wavelength of 632.8 nm. Because photorefractive impacts are essential in the buck-type modulator at a wavelength of 532 nm, it is difficult to obtain reliable phase measurements, whereas the stable phase operation of the homemade one allows the measurement sensitivity to be improved up to 30 deg/°C with the best measurement resolution at about 0.07 °C for 532 nm. PMID:22163429

Power plant maintenance scheduling using ant colony optimization: an improved formulation

NASA Astrophysics Data System (ADS)

Foong, Wai Kuan; Maier, Holger; Simpson, Angus

2008-04-01

It is common practice in the hydropower industry to either shorten the maintenance duration or to postpone maintenance tasks in a hydropower system when there is expected unserved energy based on current water storage levels and forecast storage inflows. It is therefore essential that a maintenance scheduling optimizer can incorporate the options of shortening the maintenance duration and/or deferring maintenance tasks in the search for practical maintenance schedules. In this article, an improved ant colony optimization-power plant maintenance scheduling optimization (ACO-PPMSO) formulation that considers such options in the optimization process is introduced. As a result, both the optimum commencement time and the optimum outage duration are determined for each of the maintenance tasks that need to be scheduled. In addition, a local search strategy is presented in this article to boost the robustness of the algorithm. When tested on a five-station hydropower system problem, the improved formulation is shown to be capable of allowing shortening of maintenance duration in the event of expected demand shortfalls. In addition, the new local search strategy is also shown to have significantly improved the optimization ability of the ACO-PPMSO algorithm.

Historical and Current U.S. Strategies for Boosting Distributed Generation

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

Lowder, Travis; Schwabe, Paul; Zhou, Ella

2015-10-29

This report seeks to introduce a variety of top-down and bottom-up practices that, in concert with the macro-environment of cost-reduction globally and early adoption in Europe, helped boost the distributed generation photovoltaic market in the United States. These experiences may serve as a reference in China's quest to promote distributed renewable energy.

32. 15HORSE POWER METROPOLITAN SIDECRANK SELF CONTAINED STEAM ENGINE, MANUFACTURED ...

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

32. 15-HORSE POWER METROPOLITAN SIDE-CRANK SELF CONTAINED STEAM ENGINE, MANUFACTURED BY DONEGAN & SWIFT OF NEW YORK. IT WAS PURCHASED IN 1903, AND WAS USED AT THE FIRST MORAVIAN POTTERY AND TILE WORKS BEFORE BEING MOVED TO THE CURRENT LOCATION IN 1912. THE ENGINE POWERED THE BRICK AUGER AND VERTICAL PUG MILL BY MEANS OF THE LINE SHAFT IN THE UPPER LEFT OF THE PHOTO. CLAY AND GLAZE MATERIALS ARE IN THE BACKGROUND. - Moravian Pottery & Tile Works, Southwest side of State Route 313 (Swamp Road), Northwest of East Court Street, Doylestown, Bucks County, PA

E-mail, decisional styles, and rest breaks.

PubMed

Baker, James R; Phillips, James G

2007-10-01

E-mail is a common but problematic work application. A scale was created to measure tendencies to use e-mail to take breaks (e-breaking); and self-esteem and decisional style (vigilance, procrastination, buck-passing, hypervigilance) were used to predict the self-reported and actual e-mail behaviors of 133 participants (students and marketing employees). Individuals who were low in defensive avoidance (buck-passing) engaged in more e-mailing per week, both in time spent on e-mail and message volume. E-breakers were more likely to engage in behavioral procrastination and spent more time on personal e-mail.

Multivariate Boosting for Integrative Analysis of High-Dimensional Cancer Genomic Data

PubMed Central

Xiong, Lie; Kuan, Pei-Fen; Tian, Jianan; Keles, Sunduz; Wang, Sijian

2015-01-01

In this paper, we propose a novel multivariate component-wise boosting method for fitting multivariate response regression models under the high-dimension, low sample size setting. Our method is motivated by modeling the association among different biological molecules based on multiple types of high-dimensional genomic data. Particularly, we are interested in two applications: studying the influence of DNA copy number alterations on RNA transcript levels and investigating the association between DNA methylation and gene expression. For this purpose, we model the dependence of the RNA expression levels on DNA copy number alterations and the dependence of gene expression on DNA methylation through multivariate regression models and utilize boosting-type method to handle the high dimensionality as well as model the possible nonlinear associations. The performance of the proposed method is demonstrated through simulation studies. Finally, our multivariate boosting method is applied to two breast cancer studies. PMID:26609213

Non-isolated 30 kW class arcjet PCU

NASA Astrophysics Data System (ADS)

Wong, See-Pok; Britt, Edward J.

1994-03-01

A 30 kW class arcjet Power Conditioning Unit, PCU, was built and tested during this Phase 2 SBIR contract. The PCU is an improved version of two previously developed PCU's. All of these units are 3-phase, 20 kHz buck regulators with current mode feed back to modulate the duty cycle to control the arcjet current at any selected operating point. The steady state control can assure arcjet stability despite the negative dynamic resistance of the arc discharge. The system also has a circuit to produce a high voltage start pulse to breakdown the gas and initiate the arc. The start pulse is formed by temporarily switching a short current path across the output terminals with a special solid state switching array. The switches then open rapidly, and the energy stored in the output inductors of the buck regulator produces a pulse of approximately 2500 V for approximately 500 nsec. The system was tested and modified until the transition to steady operation occurred after start up with a very small surge current overshoot. The system also can withstand a direct short circuit across the output without damage. The automatic feed back control simply reduces the duty cycle to hold the current at the set point. When the short is removed the full power output is immediately restored. This latest version arcjet PCU is conduction cooled to remove waste heat by conduction to the base plate. This unit is closer to flight a type of design than the previous functional bread boards. Waste heat is small because the PCU has a very high efficiency, 296 percent. The PCU was extensively tested with resistor loads to simulate operation with an arcjet. The unit was tested with ammonia arcjets at the Jet Propulsion Laboratory. Approximately 400 hours of testing were completed, with several starts. Many hours were also demonstrated with resistive loads.

Non-isolated 30 kW class arcjet PCU

NASA Technical Reports Server (NTRS)

Wong, See-Pok; Britt, Edward J.

1994-01-01

A 30 kW class arcjet Power Conditioning Unit, PCU, was built and tested during this Phase 2 SBIR contract. The PCU is an improved version of two previously developed PCU's. All of these units are 3-phase, 20 kHz buck regulators with current mode feed back to modulate the duty cycle to control the arcjet current at any selected operating point. The steady state control can assure arcjet stability despite the negative dynamic resistance of the arc discharge. The system also has a circuit to produce a high voltage start pulse to breakdown the gas and initiate the arc. The start pulse is formed by temporarily switching a short current path across the output terminals with a special solid state switching array. The switches then open rapidly, and the energy stored in the output inductors of the buck regulator produces a pulse of approximately 2500 V for approximately 500 nsec. The system was tested and modified until the transition to steady operation occurred after start up with a very small surge current overshoot. The system also can withstand a direct short circuit across the output without damage. The automatic feed back control simply reduces the duty cycle to hold the current at the set point. When the short is removed the full power output is immediately restored. This latest version arcjet PCU is conduction cooled to remove waste heat by conduction to the base plate. This unit is closer to flight a type of design than the previous functional bread boards. Waste heat is small because the PCU has a very high efficiency, 296 percent. The PCU was extensively tested with resistor loads to simulate operation with an arcjet. The unit was tested with ammonia arcjets at the Jet Propulsion Laboratory. Approximately 400 hours of testing were completed, with several starts. Many hours were also demonstrated with resistive loads. Some testing with hydrogen arcjets was also carried out at NASA LeRC. This system concept is now the design base for the ATTD program.

Continuous light after a long-day treatment is equivalent to melatonin implants to stimulate testosterone secretion in Alpine male goats.

PubMed

Delgadillo, J A; Vélez, L I; Flores, J A

2016-04-01

In rams, artificial long days followed by continuous light stimulate testosterone secretion during the non-breeding season. The objective of this study was to determine whether artificial long days followed by continuous light could stimulate testosterone secretion in Alpine bucks as well as in those exposed to long days followed by a melatonin treatment. All bucks were kept in shaded open pens. Control males were exposed to natural photoperiod conditions (n=5). Males of the two experimental groups were exposed to 2.5 months of long days from 1 December (n=5 each). On 16 February, one group of males was exposed to 24 h of light per day until 30 June; the other group was exposed to natural variations of photoperiod and received two s.c. melatonin implants. Testicular weight was determined every 2 weeks, and the plasma testosterone concentrations once a week. In the control and the two photoperiodic-treated groups, a treatment×time interaction was detected for testicular weight and plasma testosterone concentrations (P<0.001). In control bucks, testicular weight increased from January and peaked in June, whereas in both photoperiodic-treated groups, this variable increased from January, but peaked in April, when the values were higher than in controls (P<0.05). In the control group, plasma testosterone concentrations remained low from January to June, whereas in both photoperiodic-treated groups, this variable remained low from January to March; thereafter, these levels increased in both photoperiodic-treated groups, and were higher than controls in April and May (P<0.05). We conclude that continuous light after a long-day treatment stimulate testosterone secretion in Alpine male goats during the non-breeding season as well as the long days followed by a melatonin treatment. Therefore, continuous light could replace the implants of melatonin.

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

Heijst, T C F van; Hoekstra, N; Philippens, M E P

Purpose: The Utrecht MRI-linac (MRL) design enables new MR-guided radiotherapy (RT) approaches. This is a feasibility study for a single-fraction high dose (boost) to individual lymph nodes (LNs) in breast-cancer patients, after breast-conserving surgery (BCS) and hypofractionated whole-breast irradiation (WBI) with conventional axillary RT (AxRT). Methods: After written informed consent, 5 breast-cancer patients (cT1-3N0) were enrolled (NL500460.041.14 trial) and underwent 1.5T MRI in supine RT position, after BCS. Axillary levels, based on ESTRO guidelines, and organs-at-risk (OARs) – including lungs, chest wall, plexus and neurovascular bundle (NVB) – were delineated. Pseudo-CT scans (pCTs) were generated by HU bulk-assignment of water,more » lung, and air. With Monaco treatment-planning software (TPS Elekta), VMAT plans were generated for simultaneous WBI and AxRT, prescribing 16×2.66=42.56Gy (V95%>99% V107%<2cc). Two scenarios were considered: AxRT of levels I–II; AxRT of levels I–IV, depending on boost location. Per patient, 4 LNs with varying axillary locations were selected, delineated, and expanded to PTV with 2-mm margin. Using dedicated MRL TPS, accounting for magnetic-field effects, an IMRT 1×8.5Gy boost was simulated for each LN, to achieve a total target dose of 66Gy EQD2 (α/β=3.5Gy). WBI/ART doses and boost doses were added, and evaluated in EQD2. Results: For all scenarios, 1×8.5Gy boosts could be simulated within clinical constraints for a 66Gy total dose, in addition to WBI/AxRT. LN target coverage was excellent (V95%>95%, mean >8.5Gy). Additional dose to OARs was limited. Conclusion: Our study explored the concept of LN boosting using on-line MRI guidance. It is feasible to boost individual axillary LNs – with 2-mm margin – with an additional 1×8.5Gy, in all axillary levels, within clinical constraints. This may lead to more personalized RT approaches for patients with involved LNs and may reduce RT-induced toxicity, or the need for axillary surgery. Other LN boost strategies, including dose escalation, are under investigation.« less

Distributed photovoltaic architecture powering a DC bus: Impact of duty cycle and load variations on the efficiency of the generator

NASA Astrophysics Data System (ADS)

Allouache, Hadj; Zegaoui, Abdallah; Boutoubat, Mohamed; Bokhtache, Aicha Aissa; Kessaissia, Fatma Zohra; Charles, Jean-Pierre; Aillerie, Michel

2018-05-01

This paper focuses on a photovoltaic generator feeding a load via a boost converter in a distributed PV architecture. The principal target is the evaluation of the efficiency of a distributed photovoltaic architecture powering a direct current (DC) PV bus. This task is achieved by outlining an original way for tracking the Maximum Power Point (MPP) taking into account load variations and duty cycle on the electrical quantities of the boost converter and on the PV generator output apparent impedance. Thereafter, in a given sized PV system, we analyze the influence of the load variations on the behavior of the boost converter and we deduce the limits imposed by the load on the DC PV bus. The simultaneous influences of 1- the variation of the duty cycle of the boost converter and 2- the load power on the parameters of the various components of the photovoltaic chain and on the boost performances are clearly presented as deduced by simulation.

Factors Associated with Resilience of Adult Survivors Five Years after the 2008 Sichuan Earthquake in China

PubMed Central

Ni, Cuiping; Chow, Meyrick Chum Ming; Jiang, Xiaolian; Li, Sijian; Pang, Samantha Mei Che

2015-01-01

Given the paucity of quantitative empirical research on survivors’ resilience and its predictors in the context of long-term recovery after disasters, we examined how resilience predictors differed by gender among adult survivors five years after the Sichuan earthquake. This was a cross-sectional survey study of adult survivors (N = 495; aged 18–60) living in reconstructed communities five years into the recovery process after the Wenchuan earthquake. The instruments we used included assessments of sociodemographic characteristics and earthquake exposure level, the Connor-Davidson Resilience Scale, and the Social Support Rating Scale. Support-seeking behaviors emerged as a significant predictor of male survivors’ resilience, while subjective support and marital status were found to be predictors of female survivors’ resilience. Annual household income and chronic disease were predictors for both male and female groups. The findings of this study can be used in devising methods to boost survivors’ resilience by promoting their satisfaction with social support and their ability to obtain effective support. Additionally, the results suggest how to assist survivors who may have relatively poor resilience. PMID:25811775

Effects of gasoline reactivity and ethanol content on boosted premixed and partially stratified low-temperature gasoline combustion (LTGC)

DOE PAGES

Dec, John E.; Yang, Yi; Ji, Chunsheng; ...

2015-04-14

Low-temperature gasoline combustion (LTGC), based on the compression ignition of a premixed or partially premixed dilute charge, can provide thermal efficiencies (TE) and maximum loads comparable to those of turbo-charged diesel engines, and ultra-low NOx and particulate emissions. Intake boosting is key to achieving high loads with dilute combustion, and it also enhances the fuel's autoignition reactivity, reducing the required intake heating or hot residuals. These effects have the advantages of increasing TE and charge density, allowing greater timing retard with good stability, and making the fuel Φ- sensitive so that partial fuel stratification (PFS) can be applied for highermore » loads and further TE improvements. However, at high boost the autoignition reactivity enhancement can become excessive, and substantial amounts of EGR are required to prevent overly advanced combustion. Accordingly, an experimental investigation has been conducted to determine how the tradeoff between the effects of intake boost varies with fuel-type and its impact on load range and TE. Five fuels are investigated: a conventional AKI=87 petroleum-based gasoline (E0), and blends of 10 and 20% ethanol with this gasoline to reduce its reactivity enhancement with boost (E10 and E20). Furthermore, a second zero-ethanol gasoline with AKI=93 (matching that of E20) was also investigated (CF-E0), and some neat ethanol data are also reported.« less

Ad35 and Ad26 Vaccine Vectors Induce Potent and Cross-Reactive Antibody and T-Cell Responses to Multiple Filovirus Species

PubMed Central

Zahn, Roland; Gillisen, Gert; Roos, Anna; Koning, Marina; van der Helm, Esmeralda; Spek, Dirk; Weijtens, Mo; Grazia Pau, Maria; Radošević, Katarina; Weverling, Gerrit Jan; Custers, Jerome; Vellinga, Jort; Schuitemaker, Hanneke; Goudsmit, Jaap; Rodríguez, Ariane

2012-01-01

Filoviruses cause sporadic but highly lethal outbreaks of hemorrhagic fever in Africa in the human population. Currently, no drug or vaccine is available for treatment or prevention. A previous study with a vaccine candidate based on the low seroprevalent adenoviruses 26 and 35 (Ad26 and Ad35) was shown to provide protection against homologous Ebola Zaire challenge in non human primates (NHP) if applied in a prime-boost regimen. Here we have aimed to expand this principle to construct and evaluate Ad26 and Ad35 vectors for development of a vaccine to provide universal filovirus protection against all highly lethal strains that have caused major outbreaks in the past. We have therefore performed a phylogenetic analysis of filovirus glycoproteins to select the glycoproteins from two Ebola species (Ebola Zaire and Ebola Sudan/Gulu,), two Marburg strains (Marburg Angola and Marburg Ravn) and added the more distant non-lethal Ebola Ivory Coast species for broadest coverage. Ad26 and Ad35 vectors expressing these five filovirus glycoproteins were evaluated to induce a potent cellular and humoral immune response in mice. All adenoviral vectors induced a humoral immune response after single vaccination in a dose dependent manner that was cross-reactive within the Ebola and Marburg lineages. In addition, both strain-specific as well as cross-reactive T cell responses could be detected. A heterologous Ad26–Ad35 prime-boost regime enhanced mainly the humoral and to a lower extend the cellular immune response against the transgene. Combination of the five selected filovirus glycoproteins in one multivalent vaccine potentially elicits protective immunity in man against all major filovirus strains that have caused lethal outbreaks in the last 20 years. PMID:23236343

Diode magnetic-field influence on radiographic spot size

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

Ekdahl, Carl A. Jr.

2012-09-04

Flash radiography of hydrodynamic experiments driven by high explosives is a well-known diagnostic technique in use at many laboratories. The Dual-Axis Radiography for Hydrodynamic Testing (DARHT) facility at Los Alamos was developed for flash radiography of large hydrodynamic experiments. Two linear induction accelerators (LIAs) produce the bremsstrahlung radiographic source spots for orthogonal views of each experiment ('hydrotest'). The 2-kA, 20-MeV Axis-I LIA creates a single 60-ns radiography pulse. For time resolution of the hydrotest dynamics, the 1.7-kA, 16.5-MeV Axis-II LIA creates up to four radiography pulses by slicing them out of a longer pulse that has a 1.6-{micro}s flattop. Bothmore » axes now routinely produce radiographic source spot sizes having full-width at half-maximum (FWHM) less than 1 mm. To further improve on the radiographic resolution, one must consider the major factors influencing the spot size: (1) Beam convergence at the final focus; (2) Beam emittance; (3) Beam canonical angular momentum; (4) Beam-motion blur; and (5) Beam-target interactions. Beam emittance growth and motion in the accelerators have been addressed by careful tuning. Defocusing by beam-target interactions has been minimized through tuning of the final focus solenoid for optimum convergence and other means. Finally, the beam canonical angular momentum is minimized by using a 'shielded source' of electrons. An ideal shielded source creates the beam in a region where the axial magnetic field is zero, thus the canonical momentum zero, since the beam is born with no mechanical angular momentum. It then follows from Busch's conservation theorem that the canonical angular momentum is minimized at the target, at least in principal. In the DARHT accelerators, the axial magnetic field at the cathode is minmized by using a 'bucking coil' solenoid with reverse polarity to cancel out whatever solenoidal beam transport field exists there. This is imperfect in practice, because of radial variation of the total field across the cathode surface, solenoid misalignments, and long-term variability of solenoid fields for given currents. Therefore, it is useful to quantify the relative importance of canonical momentum in determining the focal spot, and to establish a systematic methodology for tuning the bucking coils for minimum spot size. That is the purpose of this article. Section II provides a theoretical foundation for understanding the relative importance of the canonical momentum. Section III describes the results of simulations used to quantify beam parameters, including the momentum, for each of the accelerators. Section IV compares the two accelerators, especially with respect to mis-tuned bucking coils. Finally, Section IV concludes with a methodology for optimizing the bucking coil settings.« less

Identification of water-bearing zones by the use of geophysical logs and borehole television surveys, collected February to September 1997, at the Former Naval Air Warfare Center, Warminster, Bucks County, Pennsylvania

USGS Publications Warehouse

Conger, Randall W.

1998-01-01

Between February 1997 and September 1997, 10 monitor wells were drilled near the site of the former Naval Air Warfare Center, Warminster, Bucks County, Pa., to monitor water levels and sample ground-water contaminants in the shallow, intermediate, and deep water-bearing zones. The sampling will determine the horizontal and vertical distribution of contaminated ground water migrating from known or suspected contaminant sources. Four wells were drilled north of the property adjacent to Area A, three wells along strike located on Lewis Drive, and three wells directly down dip on Ivyland Road. Well depths range from 69 feet to 300 feet below land surface.Borehole-geophysical logging and television surveys were used to identify water-bearing zones so that appropriate intervals could be screened in each monitor well. Geophysical logs were obtained at the 10 monitor wells. Borehole television surveys were obtained at the four monitor wells adjacent to Area A.Caliper and borehole television surveys were used to locate fractures, inflections on fluidtemperature and fluid-resistivity logs were used to locate possible water-bearing fractures, and heatpulse- flowmeter measurements verified these locations. Natural-gamma logs provided information on stratigraphy. After interpretation of geophysical logs, borehole television surveys, and driller's logs, all wells were screened such that water-level fluctuations could be monitored and water samples collected from discrete water-bearing zones in each borehole.

Identification of water-bearing fractures by the use of geophysical logs, May to July 1998, former Naval Air Warfare Center, Bucks County, Pennsylvania

USGS Publications Warehouse

Conger, Randall W.; Bird, Philip H.

1999-01-01

Between May and July 1998, 10 monitor wells were drilled near the site of the former Naval Air Warfare Center (NAWC), Warminster, Bucks County, Pa., to monitor water levels and sample ground water in shallow and intermediate water-bearing fractures. The sampling will determine the horizontal and vertical distribution of contaminated ground water migrating from known or suspected sources. Three boreholes were drilled on the property at 960 Jacksonville Road, at the northwestern side of NAWC, along strike from Area A; seven boreholes were drilled in Area B in the southeastern corner of NAWC. Depths range from 40.5 to 150 feet below land surface.Borehole geophysical logging and video surveys were used to identify water-bearing fractures so that appropriate intervals could be screened in each monitor well. Geophysical logs were obtained at the 10 monitor wells. Video surveys were obtained at three monitor wells in the southeastern corner of the NAWC property.Caliper logs and video surveys were used to locate fractures. Inflections on fluid-temperature and fluid-resistivity logs were used to locate possible water-bearing fractures. Heatpulse-flowmeter measurements verified these locations. Natural-gamma logs provided information on stratigraphy. After interpretation of geophysical logs, video surveys, and driller's logs, all wells were screened such that water-level fluctuations could be monitored and water samples collected from discrete water-bearing fractures in each monitor well.

Population pharmacokinetic drug–drug interaction pooled analysis of existing data for rifabutin and HIV PIs

PubMed Central

Hennig, Stefanie; Svensson, Elin M.; Niebecker, Ronald; Fourie, P. Bernard; Weiner, Marc H.; Bonora, Stefano; Peloquin, Charles A.; Gallicano, Keith; Flexner, Charles; Pym, Alex; Vis, Peter; Olliaro, Piero L.; McIlleron, Helen; Karlsson, Mats O.

2016-01-01

Objectives Extensive but fragmented data from existing studies were used to describe the drug–drug interaction between rifabutin and HIV PIs and predict doses achieving recommended therapeutic exposure for rifabutin in patients with HIV-associated TB, with concurrently administered PIs. Methods Individual-level data from 13 published studies were pooled and a population analysis approach was used to develop a pharmacokinetic model for rifabutin, its main active metabolite 25-O-desacetyl rifabutin (des-rifabutin) and drug–drug interaction with PIs in healthy volunteers and patients who had HIV and TB (TB/HIV). Results Key parameters of rifabutin affected by drug–drug interaction in TB/HIV were clearance to routes other than des-rifabutin (reduced by 76%–100%), formation of the metabolite (increased by 224% in patients), volume of distribution (increased by 606%) and distribution to the peripheral compartment (reduced by 47%). For des-rifabutin, clearance was reduced by 35%–76% and volume of distribution increased by 67%–240% in TB/HIV. These changes resulted in overall increased exposure to rifabutin in TB/HIV patients by 210% because of the effects of PIs and 280% with ritonavir-boosted PIs. Conclusions Given together with non-boosted or ritonavir-boosted PIs, rifabutin at 150 mg once daily results in similar or higher exposure compared with rifabutin at 300 mg once daily without concomitant PIs and may achieve peak concentrations within an acceptable therapeutic range. Although 300 mg of rifabutin every 3 days with boosted PI achieves an average equivalent exposure, intermittent doses of rifamycins are not supported by current guidelines. PMID:26832753

Dialog detection in narrative video by shot and face analysis

NASA Astrophysics Data System (ADS)

Kroon, B.; Nesvadba, J.; Hanjalic, A.

2007-01-01

The proliferation of captured personal and broadcast content in personal consumer archives necessitates comfortable access to stored audiovisual content. Intuitive retrieval and navigation solutions require however a semantic level that cannot be reached by generic multimedia content analysis alone. A fusion with film grammar rules can help to boost the reliability significantly. The current paper describes the fusion of low-level content analysis cues including face parameters and inter-shot similarities to segment commercial content into film grammar rule-based entities and subsequently classify those sequences into so-called shot reverse shots, i.e. dialog sequences. Moreover shot reverse shot specific mid-level cues are analyzed augmenting the shot reverse shot information with dialog specific descriptions.

Boosting current generation in microbial fuel cells by an order of magnitude by coating an ionic liquid polymer on carbon anodes.

PubMed

Yang, Lu; Deng, Wenfang; Zhang, Youming; Tan, Yueming; Ma, Ming; Xie, Qingji

2017-05-15

Microbial fuel cells (MFCs) have attracted great attentions due to their great application potentials, but the relatively low power densities of MFCs still hinder their widespread practical applications. Herein, we report that the current generation in MFCs can be boosted by an order of magnitude, simply by coating a hydrophilic and positively charged ionic liquid polymer (ILP) on carbon cloth (CC) or carbon felt (CF). The ILP coating not only can increase the bacterial loading capacity due to the electrostatic interactions between ILP and bacterial cells, but also can improve the mediated extracellular electron transfer between the electrode and the cytochrome proteins on the outer membrane of Shewanella putrefaciens cells. As a result, the maximum power density of a MFC equipped with the CF-ILP bioanode is as high as 4400±170mWm -2 , which is amongst the highest values reported to date. This work demonstrates a new strategy for greatly boosting the current generation in MFCs. Copyright © 2017 Elsevier B.V. All rights reserved.

Wavemill Product Assessment- Defining Products and Evaluating Potential Performance from a Novel Spaceborne Interferometric SAR

NASA Astrophysics Data System (ADS)

Cotton, P. D.; Gommenginger, C.; Martin, A.; Marquez, J.; Burbidge, G.; Quilfen, Y.; Chapron, B.; Reppucci, A.; Buck, C.

2016-08-01

Ocean Surface Currents are one of the most important ocean properties for oceanographers and operators in the maritime domain. Improved monitoring of ocean currents is systematically the number one requirement that emerges from any science or end user requirement surveys.Wavemill is a novel hybrid interferometric SAR system first proposed by ESA/ESTEC [Buck, 2005]. It offers the possibility of generating two-dimensional wide swath, high resolution, high precision maps of surface current vectors and ocean topography [Buck et al., 2009]. Based on a single spacecraft, it avoids the difficulties of synchronisation and baseline estimation associated with other interferometric SAR systems based on two or more satellites (e.g. the "cartwheel" or "helix" concept).The Wavemill concept has developed steadily since its first inception in 2005. A number of Wavemill studies in recent years have gradually put together facts and figures to support the case for Wavemill as a possible space-borne mission.The Wavemill Product Assessment study (WaPA) aimed to define the scientific capabilities and limitations of a spaceborne Wavemill instrument in preparation for a possible submission of the Wavemill concept as a candidate Earth Explorer Core mission. The WaPA project team brought together expert scientists and engineers in the field of SAR imaging of ocean currents, and included the National Oceanography Centre (UK), Starlab (Spain), IFREMER (France) and Airbus Defence and Space (UK). Overall project management was provided by Satellite Oceanographic Consultants (UK). The approach taken included:- A review of SAR imaging of ocean currents in along-track interferometric mode to learn from previous experiments and modelling what key phenomena need to be accounted for to determine the true performance of a spaceborne Wavemill system- Validation of proposed Wavemill primary products based on Wavemill airborne proof-of-concept data and numerical simulations to determine the capabilities and limitations of a spaceborne Wavemill instrument for ocean current vector and sea surface height mapping.- An analysis of the potential for ocean wind vector retrieval from a spaceborne Wavemill instrument.- An investigation of possible secondary products from Wavemill relating to rivers, ocean/atmosphere interactions, ocean swell and cryospheric applications.An assessment of the synergy between Wavemill and ocean surface current products derived from other remote sensing techniques, accounting for the nature and variability of the measured properties, to identify any additional requirements on a future Wavemill mission.

An Optimized Air-Core Coil Sensor with a Magnetic Flux Compensation Structure Suitable to the Helicopter TEM System.

PubMed

Chen, Chen; Liu, Fei; Lin, Jun; Zhu, Kaiguang; Wang, Yanzhang

2016-04-12

The air-core coil sensor (ACS) is widely used as a transducer to measure the variation in magnetic fields of a helicopter transient electromagnetic (TEM) system. A high periodic emitting current induces the magnetic field signal of the underground medium. However, such current also generates a high primary field signal that can affect the received signal of the ACS and even damage the receiver. To increase the dynamic range of the received signal and to protect the receiver when emitting current rises/falls, the combination of ACS with magnetic flux compensation structure (bucking coil) is necessary. Moreover, the optimized ACS, which is composed of an air-core coil and a differential pre-amplifier circuit, must be investigated to meet the requirements of the helicopter TEM system suited to rapid surveying for shallow buried metal mine in rough topography. Accordingly, two ACSs are fabricated in this study, and their performance is verified and compared inside a magnetic shielding room. Using the designed ACSs, field experiments are conducted in Baoqing County. The field experimental data show that the primary field response can be compensated when the bucking coil is placed at an appropriate point in the range of allowed shift distance beyond the center of the transmitting coil and that the damage to the receiver induced by the over-statured signal can be solved. In conclusion, a more suitable ACS is adopted and is shown to have better performance, with a mass of 2.5 kg, resultant effective area of 11.6 m² (i.e., diameter of 0.496 m), 3 dB bandwidth of 66 kHz, signal-to-noise ratio of 4 (i.e., varying magnetic field strength of 0.2 nT/s), and normalized equivalent input noise of 3.62 nV/m².

Differing rates of antibody acquisition to merozoite antigens in malaria: implications for immunity and surveillance.

PubMed

McCallum, Fiona J; Persson, Kristina E M; Fowkes, Freya J I; Reiling, Linda; Mugyenyi, Cleopatra K; Richards, Jack S; Simpson, Julie A; Williams, Thomas N; Gilson, Paul R; Hodder, Anthony N; Sanders, Paul R; Anders, Robin F; Narum, David L; Chitnis, Chetan; Crabb, Brendan S; Marsh, Kevin; Beeson, James G

2017-04-01

Antibodies play a key role in acquired human immunity to Plasmodium falciparum (Pf) malaria and target merozoites to reduce or prevent blood-stage replication and the development of disease. Merozoites present a complex array of antigens to the immune system, and currently, there is only a partial understanding of the targets of protective antibodies and how responses to different antigens are acquired and boosted. We hypothesized that there would be differences in the rate of acquisition of antibodies to different antigens and how well they are boosted by infection, which impacts the acquisition of immunity. We examined responses to a range of merozoite antigens in 2 different cohorts of children and adults with different age structures and levels of malaria exposure. Overall, antibodies were associated with age, exposure, and active infection, and the repertoire of responses increased with age and active infection. However, rates of antibody acquisition varied between antigens and different regions within an antigen following exposure to malaria, supporting our hypothesis. Antigen-specific responses could be broadly classified into early response types in which antibodies were acquired early in childhood exposure and late response types that appear to require substantially more exposure for the development of substantial levels. We identified antigen-specific responses that were effectively boosted after recent infection, whereas other responses were not. These findings advance our understanding of the acquisition of human immunity to malaria and are relevant to the development of malaria vaccines targeting merozoite antigens and the selection of antigens for use in malaria surveillance. © Society for Leukocyte Biology.

Experimental Simulation of Turbine-Exhaust Oxygen Recovery

NASA Technical Reports Server (NTRS)

Clark, Jim A.; Branch, Ryan W.

2004-01-01

In some liquid-propellant rocket engines, the liquid-oxygen boost pump is driven by a turbine that is powered by high-pressure gaseous oxygen. Once it exits the turbine, this gaseous oxygen can be salvaged by injecting it into the subcooled liquid oxygen exiting the boost pump. If the main LOX pump is to function correctly under these circumstances, complete condensation of the gaseous oxygen must quickly follow its injection into the boost-pump discharge. The current investigation uses steam and water in a simple rig that allows the condensation process to be visualized and quantified. This paper offers dimensionless-parameter correlations of the data and trends observed.

Scandinavian Working Papers on Bilingualism, 2.

ERIC Educational Resources Information Center

Faerch, Claus; And Others

Five papers on bilingualism are presented. "Giving Transfer a Boost--Describing Transfer Variation in Learners' Interlanguage Performance" by Claus Faerch suggests, outlines, and illustrates a heuristic principle for describing the result of positive transfer from one language to another, based on the assumption that learners maximize…

A high efficiency 3 kW switchmode battery charger

NASA Technical Reports Server (NTRS)

Latos, T. S.; Bosack, D. J.

1982-01-01

This paper discusses the design approach and status of a high-efficiency switchmode battery charger designed to charge a 108 V battery from the 115 Vac line. The charger contains a transformer isolated boost chopper operating at 20 kHz. The boost inductor current is programmed to follow the ac line voltage such that high power factor operation and low line distortion are obtained.

What's New in Software? Current Sources of Information Boost Effectiveness of Computer-Assisted Instruction.

ERIC Educational Resources Information Center

Ellsworth, Nancy J.

1990-01-01

This article reviews current resources on computer-assisted instruction. Included are sources of software and hardware evaluations, advances in current technology, research, an information hotline, and inventories of available technological assistance. (DB)

Persistence of Protective Immunity to Malaria Induced by DNA Priming and Poxvirus Boosting: Characterization of Effector and Memory CD8+-T-Cell Populations

PubMed Central

Sedegah, Martha; Brice, Gary T.; Rogers, William O.; Doolan, Denise L.; Charoenvit, Yupin; Jones, Trevor R.; Majam, Victoria F.; Belmonte, Arnel; Lu, Minh; Belmonte, Maria; Carucci, Daniel J.; Hoffman, Stephen L.

2002-01-01

The persistence of immunity to malaria induced in mice by a heterologous DNA priming and poxvirus boosting regimen was characterized. Mice were immunized by priming with DNA vaccine plasmids encoding the Plasmodium yoelii circumsporozoite protein (PyCSP) and murine granulocyte-macrophage colony-stimulating factor and boosting with recombinant vaccinia encoding PyCSP. BALB/c mice immunized with either high-dose (100 μg of p PyCSP plus 30 μg of pGM-CSF) or low-dose (1 μg of p PyCSP plus 1 μg of pGM-CSF DNA) priming were protected against challenge with 50 P. yoelii sporozoites. Protection 2 weeks after immunization was 70 to 100%, persisted at this level for at least 20 weeks, and declined to 30 to 40% by 28 weeks. Eight of eight mice protected at 20 weeks were still protected when rechallenged at 40 weeks. The antigen (Ag)-specific effector CD8+-T-cell population present 2 weeks after boosting had ex vivo Ag-specific cytolytic activity, expressed both gamma interferon (IFN-γ) and tumor necrosis factor alpha, and constituted 12 to 20% of splenic CD8+ T cells. In contrast, the memory CD8+-Ag-specific-cell population at 28 weeks lacked cytolytic activity and constituted only 6% of splenic CD8+ T cells, but at the single-cell level it produced significantly higher levels of IFN-γ than the effectors. High levels of Ag- or parasite-specific antibodies present 2 weeks after boosting had declined three- to sevenfold by 28 weeks. Low-dose priming was similarly immunogenic and as protective as high-dose priming against a 50-, but not a 250-, sporozoite challenge. These results demonstrate that a heterologous priming and boosting vaccination can provide lasting protection against malaria in this model system. PMID:12065488

The impact of 2-dose routine measles, mumps, rubella, and varicella vaccination in France on the epidemiology of varicella and zoster using a dynamic model with an empirical contact matrix.

PubMed

Ouwens, Mario J N M; Littlewood, Kavi J; Sauboin, Christophe; Téhard, Bertrand; Denis, François; Boëlle, Pierre-Yves; Alain, Sophie

2015-04-01

Varicella has a high incidence affecting the vast majority of the population in France and can lead to severe complications. Almost every individual infected by varicella becomes susceptible to herpes zoster later in life due to reactivation of the latent virus. Zoster is characterized by pain that can be long-lasting in some cases and has no satisfactory treatment. Routine varicella vaccination can prevent varicella. The vaccination strategy of replacing both doses of measles, mumps, and rubella (MMR) with a combined MMR and varicella (MMRV) vaccine is a means of reaching high vaccination coverage for varicella immunization. The objective of this analysis was to assess the impact of routine varicella vaccination, with MMRV in place of MMR, on the incidence of varicella and zoster diseases in France and to assess the impact of exogenous boosting of zoster incidence, age shift in varicella cases, and other possible indirect effects. A dynamic transmission population-based model was developed using epidemiological data for France to determine the force of infection, as well as an empirically derived contact matrix to reduce assumptions underlying these key drivers of dynamic models. Scenario analyses tested assumptions regarding exogenous boosting, vaccine waning, vaccination coverage, risk of complications, and contact matrices. The model provides a good estimate of the incidence before varicella vaccination implementation in France. When routine varicella vaccination is introduced with French current coverage levels, varicella incidence is predicted to decrease by 57%, and related complications are expected to decrease by 76% over time. After vaccination, it is observed that exogenous boosting is the main driver of change in zoster incidence. When exogenous boosting is assumed, there is a temporary increase in zoster incidence before it gradually decreases, whereas without exogenous boosting, varicella vaccination leads to a gradual decrease in zoster incidence. Changing vaccine efficacy waning levels and coverage assumptions are still predicted to result in overall benefits with varicella vaccination. In conclusion, the model predicted that MMRV vaccination can significantly reduce varicella incidence. With suboptimal coverage, a limited age shift of varicella cases is predicted to occur post-vaccination with MMRV. However, it does not result in an increase in the number of complications. GSK study identifier: HO-12-6924. Copyright © 2015 The Authors. Published by Elsevier Inc. All rights reserved.

Parental involvement and association with adolescents' fruit and vegetable intake at follow-up: Process evaluation results from the multi-component school-based Boost intervention.

PubMed

Jørgensen, Sanne Ellegård; Jørgensen, Thea Suldrup; Aarestrup, Anne Kristine; Due, Pernille; Krølner, Rikke

2016-10-26

Based on the assumption of parental influence on adolescent behavior, multicomponent school-based dietary interventions often include a parental component. The effect of this intervention component is seldom reported and the evidence is inconsistent. We conducted a systematic process evaluation of the parental component and examined whether the leveal of parental involvement in a large multi-component intervention: the Boost study was associated with adolescents' fruit and vegetable (FV) intake at follow-up. The Boost study was targeting FV intake among 1,175 Danish 7 th graders (≈13- year-olds) in the school year 2010/11. The study included a school component: free FV in class and curricular activities; a local community component: fact sheets for sports- and youth clubs; and a parental component: presentation of Boost at a parent-school meeting, 6 newsletters to parents, 3 guided student-parent curricular activities, and a student-parent Boost event. Students whose parent replied to the follow-up survey (n = 347). Questionnaire data from students, parents and teachers at 20 intervention schools. Process evaluation measures: dose delivered, dose received, appreciation and level of parental involvement. Parental involvement was trichotomized into: low/no (0-2 points), medium (3 points) and high (4-6 points). The association between level of parental involvement and self-reported FV intake (24-h recall), was analyzed using multilevel regression analyses. The Boost study was presented at a parent-school meeting at all intervention schools. The dose delivered was low to moderate for the three other parental elements. Most parents appreciated the intervention and talked with their child about Boost (83.5 %). High, medium and low parental involvement was found among 30.5 %, 29.6 % and 39.4 % of the students respectively. Parental involvement was highest among women. More men agreed that the parental newsletters provided new information. Students with a medium and high level of parental involvement ate 47.5 and 95.2 g more FV per day compared to students with low level/no parental involvement (p = 0.02). Students with a high level of parental involvement ate significantly more FV at follow-up compared to students with a low level/no parental involvement. Parental involvement in interventions may improve adolescents' FV intake if challenges of implementation can be overcome. ISRCTN11666034 . Registered 06/01/2012. Retrospectively registered.

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

Shusharina, N; Khan, F; Sharp, G

Purpose: To determine the dose level and timing of the boost in locally advanced lung cancer patients with confirmed tumor recurrence by comparing different boosting strategies by an impact of dose escalation in improvement of the therapeutic ratio. Methods: We selected eighteen patients with advanced NSCLC and confirmed recurrence. For each patient, a base IMRT plan to 60 Gy prescribed to PTV was created. Then we compared three dose escalation strategies: a uniform escalation to the original PTV, an escalation to a PET-defined target planned sequentially and concurrently. The PET-defined targets were delineated by biologically-weighed regions on a pre-treatment 18F-FDGmore » PET. The maximal achievable dose, without violating the OAR constraints, was identified for each boosting method. The EUD for the target, spinal cord, combined lung, and esophagus was compared for each plan. Results: The average prescribed dose was 70.4±13.9 Gy for the uniform boost, 88.5±15.9 Gy for the sequential boost and 89.1±16.5 Gy for concurrent boost. The size of the boost planning volume was 12.8% (range: 1.4 – 27.9%) of the PTV. The most prescription-limiting dose constraints was the V70 of the esophagus. The EUD within the target increased by 10.6 Gy for the uniform boost, by 31.4 Gy for the sequential boost and by 38.2 for the concurrent boost. The EUD for OARs increased by the following amounts: spinal cord, 3.1 Gy for uniform boost, 2.8 Gy for sequential boost, 5.8 Gy for concurrent boost; combined lung, 1.6 Gy for uniform, 1.1 Gy for sequential, 2.8 Gy for concurrent; esophagus, 4.2 Gy for uniform, 1.3 Gy for sequential, 5.6 Gy for concurrent. Conclusion: Dose escalation to a biologically-weighed gross tumor volume defined on a pre-treatment 18F-FDG PET may provide improved therapeutic ratio without breaching predefined OAR constraints. Sequential boost provides better sparing of OARs as compared with concurrent boost.« less

A 190 mV start-up and 59.2% efficiency CMOS gate boosting voltage doubler charge pump in 0.18 µm standard CMOS process for energy harvesting

NASA Astrophysics Data System (ADS)

Yoshida, Minori; Miyaji, Kousuke

2018-04-01

A start-up charge pump circuit for an extremely low input voltage (V IN) is proposed and demonstrated. The proposed circuit uses an inverter level shifter to generate a 2V IN voltage swing to the gate of both main NMOS and PMOS power transistors in a charge pump to reduce the channel resistance. The proposed circuit is fully implemented in a standard 0.18 µm CMOS process, and the measurement result shows that a minimum input voltage of 190 mV is achieved and output power increases by 181% compared with the conventional forward-body-bias scheme at a 300 mV input voltage. The proposed scheme achieves a maximum efficiency of 59.2% when the input voltage is 390 mV and the output current is 320 nA. The proposed circuit is suitable as a start-up circuit in ultralow power energy harvesting power management applications to boost-up from below threshold voltage.

The MSPICE simulation of a saturating transformer

NASA Astrophysics Data System (ADS)

Maclean, David N.

A transformer is simulated using a nonlinear saturating magnetic model. Hysteresis and gradual smooth reduction of core permeability are achieved with standard SPICE networks and functions. The equations that define the nonlinear inductance and the MSPICE circuits used to simulate them are derived. A hierarchy of circuit complexity that is based on the structured logic design subcircuit method is used. An example of a push-pull buck regulator being operated in an unbalanced condition is given. Noise ripple on the input power cable generates a dc offset current in the transformer. The example demonstrates how avionics power equipment can be evaluated for large-signal ac, dc, and transient behavior.

Safety and immunogenicity of mammalian cell derived and Modified Vaccinia Ankara vectored African swine fever subunit antigens in swine.

PubMed

Lopera-Madrid, Jaime; Osorio, Jorge E; He, Yongqun; Xiang, Zuoshuang; Adams, L Garry; Laughlin, Richard C; Mwangi, Waithaka; Subramanya, Sandesh; Neilan, John; Brake, David; Burrage, Thomas G; Brown, William Clay; Clavijo, Alfonso; Bounpheng, Mangkey A

2017-03-01

A reverse vaccinology system, Vaxign, was used to identify and select a subset of five African Swine Fever (ASF) antigens that were successfully purified from human embryonic kidney 293 (HEK) cells and produced in Modified vaccinia virus Ankara (MVA) viral vectors. Three HEK-purified antigens [B646L (p72), E183L (p54), and O61R (p12)], and three MVA-vectored antigens [B646L, EP153R, and EP402R (CD2v)] were evaluated using a prime-boost immunization regimen swine safety and immunogenicity study. Antibody responses were detected in pigs following prime-boost immunization four weeks apart with the HEK-293-purified p72, p54, and p12 antigens. Notably, sera from the vaccinees were positive by immunofluorescence on ASFV (Georgia 2007/1)-infected primary macrophages. Although MVA-vectored p72, CD2v, and EP153R failed to induce antibody responses, interferon-gamma (IFN-γ + ) spot forming cell responses against all three antigens were detected one week post-boost. The highest IFN-γ + spot forming cell responses were detected against p72 in pigs primed with MVA-p72 and boosted with the recombinant p72. Antigen-specific (p12, p72, CD2v, and EP153R) T-cell proliferative responses were also detected post-boost. Collectively, these results are the first demonstration that ASFV subunit antigens purified from mammalian cells or expressed in MVA vectors are safe and can induce ASFV-specific antibody and T-cell responses following a prime-boost immunization regimen in swine. Copyright © 2017 Elsevier B.V. All rights reserved.

A Modular PMAD System for Small Spacecraft

NASA Technical Reports Server (NTRS)

Button, Robert M.

1998-01-01

Current trends in satellite design are focused on developing small, reliable, and inexpensive spacecraft. To that end, a modular power management and distribution system (PMAD) is proposed which will help transition the aerospace industry towards an assembly line approach to building spacecraft. The modular system is based on an innovative DC voltage boost converter called the Series Connected Boost Regulator (SCBR). The SCBR uses existing DC-DC converters and adds a unique series connection. This simple modification provides the SCBR topology with many advantages over existing boost converters. Efficiencies of 94-98%, power densities above 1,000 We/kg, and inherent fault tolerance are just a few of the characteristics presented. Limitations of the SCBR technology are presented, and it is shown that the SCBR makes an ideal photovoltaic array regulator. A modular design based on the series connected boost unit is outlined and functional descriptions of the components are given.

Co-Optimization of Fuels & Engines: Fuel Blendstocks with the Potential to Optimize Future Gasoline Engine Performance; Identification of Five Chemical Families for Detailed Evaluation

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

Farrell, John T; Holladay, John; Wagner, Robert

The U.S. Department of Energy's (DOE's) Co-Optimization of Fuels & Engines (Co-Optima) initiative is conducting the early-stage research needed to accelerate the market introduction of advanced fuel and engine technologies. The research includes both spark-ignition (SI) and compression-ignition (CI) combustion approaches, targeting applications that impact the entire on-road fleet (light-, medium-, and heavy-duty vehicles). The initiative's major goals include significant improvements in vehicle fuel economy, lower-cost pathways to reduce emissions, and leveraging diverse U.S. fuel resources. A key objective of Co-Optima's research is to identify new blendstocks that enhance current petroleum blending components, increase blendstock diversity, and provide refiners withmore » increased flexibility to blend fuels with the key properties required to optimize advanced internal combustion engines. This report identifies eight representative blendstocks from five chemical families that have demonstrated the potential to increase boosted SI engine efficiency, meet key fuel quality requirements, and be viable for production at commercial scale by 2025-2030.« less

A heterologous prime-boosting strategy with replicating Vaccinia virus vectors and plant-produced HIV-1 Gag/dgp41 virus-like particles

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

Meador, Lydia R.

Showing modest efficacy, the RV144 HIV-1 vaccine clinical trial utilized a non-replicating canarypox viral vector and a soluble gp120 protein boost. Here we built upon the RV144 strategy by developing a novel combination of a replicating, but highly-attenuated Vaccinia virus vector, NYVAC-KC, and plant-produced HIV-1 virus-like particles (VLPs). Both components contained the full-length Gag and a membrane anchored truncated gp41 presenting the membrane proximal external region with its conserved broadly neutralizing epitopes in the pre-fusion conformation. We tested different prime/boost combinations of these components in mice and showed that the group primed with NYVAC-KC and boosted with both the viralmore » vectors and plant-produced VLPs have the most robust Gag-specific CD8 T cell responses, at 12.7% of CD8 T cells expressing IFN-γ in response to stimulation with five Gag epitopes. The same immunization group elicited the best systemic and mucosal antibody responses to Gag and dgp41 with a bias towards IgG1. - Highlights: • We devised a prime/boost anti HIV-1 vaccination strategy modeled after RV144. • We used plant-derived virus-like particles (VLPs) consisting of Gag and dgp41. • We used attenuated, replicating vaccinia virus vectors expressing the same antigens. • The immunogens elicited strong cellular and humoral immune responses.« less

A High Temperature Silicon Carbide mosfet Power Module With Integrated Silicon-On-Insulator-Based Gate Drive

DOE PAGES

Wang, Zhiqiang; Shi, Xiaojie; Tolbert, Leon M.; ...

2014-04-30

Here we present a board-level integrated silicon carbide (SiC) MOSFET power module for high temperature and high power density application. Specifically, a silicon-on-insulator (SOI)-based gate driver capable of operating at 200°C ambient temperature is designed and fabricated. The sourcing and sinking current capability of the gate driver are tested under various ambient temperatures. Also, a 1200 V/100 A SiC MOSFET phase-leg power module is developed utilizing high temperature packaging technologies. The static characteristics, switching performance, and short-circuit behavior of the fabricated power module are fully evaluated at different temperatures. Moreover, a buck converter prototype composed of the SOI gate drivermore » and SiC power module is built for high temperature continuous operation. The converter is operated at different switching frequencies up to 100 kHz, with its junction temperature monitored by a thermosensitive electrical parameter and compared with thermal simulation results. The experimental results from the continuous operation demonstrate the high temperature capability of the power module at a junction temperature greater than 225°C.« less

Do review articles boost journal impact factors? A longitudinal analysis for five pharmacology journals.

PubMed

Amiri, Marjan; Michel, Martin C

2018-06-21

The impact factor is a frequently applied tool in research output analytics. Based on five consecutive publication years each of five pharmacology journals, we have analyzed to which extent review articles yield more impact factor-relevant citations than original articles. Our analysis shows that review articles are quoted about twice as often as original articles published in the same year in the same journal. We conclude that inclusion of review articles does not substantially affect the impact factor of a journal unless they account for considerably more than 10% of all published articles.

The American Society for Therapeutic Radiology and Oncology (ASTRO) evidence-based review of the role of radiosurgery for brain metastases

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

Mehta, Minesh P.; Tsao, May N.; Whelan, Timothy J.

2005-09-01

Purpose: To systematically review the evidence for the use of stereotactic radiosurgery in adult patients with brain metastases. Methods: Key clinical questions to be addressed in this evidence-based review were identified. Outcomes considered were overall survival, quality of life or symptom control, brain tumor control or response and toxicity. MEDLINE (1990-2004 June Week 2), CANCERLIT (1990-2003), CINAHL (1990-2004 June Week 2), EMBASE (1990-2004 Week 25), and the Cochrane library (2004 issue 2) databases were searched using OVID. In addition, the Physician Data Query clinical trials database, the proceedings of the American Society of Clinical Oncology (ASCO) (1997-2004), ASTRO (1997-2004), andmore » the European Society of Therapeutic Radiology and Oncology (ESTRO) (1997-2003) were searched. Data from the literature search were reviewed and tabulated. This process included an assessment of the level of evidence. Results: For patients with newly diagnosed brain metastases, managed with whole-brain radiotherapy alone vs. whole-brain radiotherapy and radiosurgery boost, there were three randomized controlled trials, zero prospective studies, and seven retrospective series (which satisfied inclusion criteria). For patients with up to three (<4 cm) newly diagnosed brain metastases (and in one study up to four brain metastases), radiosurgery boost with whole-brain radiotherapy significantly improves local brain control rates as compared with whole-brain radiotherapy alone (Level I-III evidence). In one large randomized trial, survival benefit with whole-brain radiotherapy was observed in patients with single brain metastasis. In this trial, an overall increased ability to taper down on steroid dose and an improvement in Karnofsky performance status was seen in patients who were treated with radiosurgery boost as compared with patients treated with whole-brain radiotherapy alone. However, Level I evidence regarding overall quality of life outcomes using a validated instrument has not been reported. All randomized trials showed improved local control with the addition of radiosurgery to whole-brain radiotherapy. For patients with multiple brain metastases, there is no overall survival benefit with the use of radiosurgery boost to whole-brain radiotherapy (Level I-III evidence). Radiosurgery boost is associated with a small risk of early or late toxicity. In patients treated with radiosurgery alone (withholding whole-brain radiotherapy) as initial treatment, there were 2 randomized trials, 2 prospective cohort studies, and 16 retrospective series. There is Level I to Level III evidence that the use of radiosurgery alone does not alter survival as compared to the use of whole-brain radiotherapy. However, there is Level I to Level III evidence that omission of whole-brain radiotherapy results in poorer intracranial disease control, both local and distant (defined as remaining brain, outside the radiosurgery field). Quality of life outcomes have not been adequately reported. Radiosurgery is associated with a small risk of early or late toxicity. Radiosurgery as salvage for patients with brain metastases was reported in zero randomized trials, one prospective study, and seven retrospective series. Conclusions: Based on Level I-III evidence, for selected patients with small (up to 4 cm) brain metastases (up to three in number and four in one randomized trial), the addition of radiosurgery boost to whole-brain radiotherapy improves brain control as compared with whole-brain radiotherapy alone. In patients with a single brain metastasis, radiosurgery boost with whole-brain radiotherapy improves survival. There is a small risk of toxicity associated with radiosurgery boost as compared with whole-brain radiotherapy alone. In selected patients treated with radiosurgery alone for newly diagnosed brain metastases, overall survival is not altered. However, local and distant brain control is significantly poorer with omission of upfront whole-brain radiotherapy (Level I-III evidence). Whether neurocognition or quality of life outcomes are different between initial radiosurgery alone vs. whole-brain radiotherapy (with or without radiosurgery boost) is unknown, because this has not been adequately tested. There was no statistically significant difference in overall toxicity between those treated with radiosurgery alone vs. whole-brain radiotherapy and radiosurgery boost based on an interim report from one randomized study. There is insufficient evidence as to the clinical benefit/risks radiosurgery used in the setting of recurrent or progressive brain metastases, although radiographic responses are well-documented.« less

Culture First: Boosting Program Strength through Cultural Instruction

ERIC Educational Resources Information Center

Windham, Scott

2017-01-01

In recent years, cultural instruction has been touted as a way to help foreign language programs boost student learning outcomes, enrollments, and many other measures of program strength. In order to investigate the relationship between cultural instruction and program strength in a university-level German program, students in first- and…

Alpha/Beta T-Cell Depleted Grafts as an Immunological Booster to Treat Graft Failure after Hematopoietic Stem Cell Transplantation with HLA-Matched Related and Unrelated Donors

PubMed Central

Rådestad, E.; Wikell, H.; Engström, M.; Watz, E.; Sundberg, B.; Thunberg, S.; Uzunel, M.; Mattsson, J.; Uhlin, M.

2014-01-01

Allogeneic hematopoietic stem cell transplantation is associated with several complications and risk factors, for example, graft versus host disease (GVHD), viral infections, relapse, and graft rejection. While high levels of CD3+ cells in grafts can contribute to GVHD, they also promote the graft versus leukemia (GVL) effect. Infusions of extra lymphocytes from the original stem cell donor can be used as a treatment after transplantation for relapse or poor immune reconstitution but also they increase the risk for GVHD. In peripheral blood, 95% of T-cells express the αβ T-cell receptor and the remaining T-cells express the γδ T-cell receptor. As αβ T-cells are the primary mediators of GVHD, depleting them from the graft should reduce this risk. In this pilot study, five patients transplanted with HLA-matched related and unrelated donors were treated with αβ T-cell depleted stem cell boosts. The majority of γδ T-cells in the grafts expressed Vδ2 and/or Vγ9. Most patients receiving αβ-depleted stem cell boosts increased their levels of white blood cells, platelets, and/or granulocytes 30 days after infusion. No signs of GVHD or other side effects were detected. A larger pool of patients with longer follow-up time is needed to confirm the data in this study. PMID:25371909

Power Strategy in DC/DC Converters to Increase Efficiency of Electrical Stimulators.

PubMed

Aqueveque, Pablo; Acuña, Vicente; Saavedra, Francisco; Debelle, Adrien; Lonys, Laurent; Julémont, Nicolas; Huberland, François; Godfraind, Carmen; Nonclercq, Antoine

2016-06-13

Power efficiency is critical for electrical stimulators. Battery life of wearable stimulators and wireless power transmission in implanted systems are common limiting factors. Boost DC/DC converters are typically needed to increase the supply voltage of the output stage. Traditionally, boost DC/DC converters are used with fast control to regulate the supply voltage of the output. However, since stimulators are acting as current sources, such voltage regulation is not needed. Banking on this, this paper presents a DC/DC conversion strategy aiming to increase power efficiency. It compares, in terms of efficiency, the traditional use of boost converters to two alternatives that could be implemented in future hardware designs.

Boosting Hispanic College Completion

ERIC Educational Resources Information Center

Gurantz, Oded; Hurwitz, Michael; Smith, Jonathan

2017-01-01

Helping raise the Hispanic college graduation rate is an urgent goal, given the persistently high rate of poverty among Hispanic families, growth of the Hispanic population to account for one in five college-age Americans, and mounting concerns about racial and economic inequality. The question is, how? One potential strategy involves helping high…

How Can Schools Boost Students' Self-Regulation?

ERIC Educational Resources Information Center

Le, Cecilia; Wolfe, Rebecca E.

2013-01-01

A striking convergence of research, documentation, commentary, and policy in the past five years strongly suggests that an almost exclusive focus on academic knowledge and skills is an incomplete solution. Additional behaviors, skills, and mindsets--sometimes called metacognitive skills or 21st-century skills--are just as necessary for academic…

Sensorless Load Torque Estimation and Passivity Based Control of Buck Converter Fed DC Motor

PubMed Central

Kumar, S. Ganesh; Thilagar, S. Hosimin

2015-01-01

Passivity based control of DC motor in sensorless configuration is proposed in this paper. Exact tracking error dynamics passive output feedback control is used for stabilizing the speed of Buck converter fed DC motor under various load torques such as constant type, fan type, propeller type, and unknown load torques. Under load conditions, sensorless online algebraic approach is proposed, and it is compared with sensorless reduced order observer approach. The former produces better response in estimating the load torque. Sensitivity analysis is also performed to select the appropriate control variables. Simulation and experimental results fully confirm the superiority of the proposed approach suggested in this paper. PMID:25893208

Towards an understanding of the correlations in jet substructure

DOE PAGES

Adams, D.; Arce, A.; Asquith, L.; ...

2015-09-09

Over the past decade, a large number of jet substructure observables have been proposed in the literature, and explored at the LHC experiments. Such observables attempt to utilize the internal structure of jets in order to distinguish those initiated by quarks, gluons, or by boosted heavy objects, such as top quarks and W bosons. This report, originating from and motivated by the BOOST2013 workshop, presents original particle-level studies that aim to improve our understanding of the relationships between jet substructure observables, their complementarity, and their dependence on the underlying jet properties, particularly the jet radius and jet transverse momentum. Thismore » is explored in the context of quark/gluon discrimination, boosted W boson tagging and boosted top quark tagging.« less

A prospective study for upper-extremity cumulative trauma disorders of workers in aircraft manufacturing.

PubMed

Melhorn, J M

1996-12-01

Occupational diseases affect 15 to 20% of all Americans. Cumulative trauma disorders (CTDs) account for 56% of all occupational injuries. The recognition and control of occupational injuries has become a major concern of employees, employers, medicine, and the federal government because of health risk and related costs. Upper-extremity CTDs are identified by the National Institute for Occupational Safety and Health as one of the ten most significant occupational health problems in the United States. It is estimated by the year 2000 that 50 cents on the dollar will be spent on CTDs. Although enlightened aircraft employers have developed primary prevention strategies, primary prevention can never be expected to eliminate 100% of the cases. To evaluate several preventive activities, a CTD risk-assessment program was developed and implemented in cooperation with a major aircraft manufacturer employing over 8000 workers. This program was focused on objectively identifying the relationship of work and other activities to an individual worker experiencing CTDs. Early identification has been linked, when applicable, to intervention algorithms for medical care, job task modification, workplace accommodation, and training. A prospective study group of 212 workers who used rivet guns was placed into a four-way experimental design for ergonomic posture training, exercise training, and rivet-gun type (primary factors). A statistical model was developed for the level of CTD risk and evaluated using the SAS software program (SAS Institute, Inc, Carry, NC). Statistical analysis of the primary factors without regard to associated variables (covariates) demonstrated that only posture training had a beneficial risk reduction for the individual. The impact (beneficial or detrimental) for exercise training and for vibration-dampening rivet guns was probably obscured because of the large variability of the responses regarding the associated variables (covariates). When the covariates were analyzed in conjunction with the four experimental groups, a positive benefit from ergonomic posture training and exercise training was demonstrated for the following groups: the dominant han, time spend in an awkward position, number of standard rivets bucked, number of parts routed, number of parts ground, number of vibration-dampening rivets bucked, and newly hired individuals. A negative effect (increase in individual risk level) for current employees using a vibration-dampening rivet gun was demonstrated. This prospective study helps to identify the possible benefit of education and training for controlling CTDs and demonstrates the usefulness of being able to evaluate materials, methods, machines, and environments as they relate to the individual's risk level for the development of upper-extremity CTDs.

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

Dec, John E.; Yang, Yi; Ji, Chunsheng

Low-temperature gasoline combustion (LTGC), based on the compression ignition of a premixed or partially premixed dilute charge, can provide thermal efficiencies (TE) and maximum loads comparable to those of turbo-charged diesel engines, and ultra-low NOx and particulate emissions. Intake boosting is key to achieving high loads with dilute combustion, and it also enhances the fuel's autoignition reactivity, reducing the required intake heating or hot residuals. These effects have the advantages of increasing TE and charge density, allowing greater timing retard with good stability, and making the fuel Φ- sensitive so that partial fuel stratification (PFS) can be applied for highermore » loads and further TE improvements. However, at high boost the autoignition reactivity enhancement can become excessive, and substantial amounts of EGR are required to prevent overly advanced combustion. Accordingly, an experimental investigation has been conducted to determine how the tradeoff between the effects of intake boost varies with fuel-type and its impact on load range and TE. Five fuels are investigated: a conventional AKI=87 petroleum-based gasoline (E0), and blends of 10 and 20% ethanol with this gasoline to reduce its reactivity enhancement with boost (E10 and E20). Furthermore, a second zero-ethanol gasoline with AKI=93 (matching that of E20) was also investigated (CF-E0), and some neat ethanol data are also reported.« less

Cura Annonae-Chemically Boosting Crop Yields Through Metabolic Feeding of a Plant Signaling Precursor.

PubMed

Vocadlo, David J

2017-05-22

The cream of the crop: With the world facing a projected shortfall of crops by 2050, new approaches are needed to boost crop yields. Metabolic feeding of plants with photocaged trehalose-6-phosphate (Tre6P) can increase levels of the signaling metabolite Tre6P in the plant. Reprogramming of cellular metabolism by Tre6P stimulates a program of plant growth and enhanced crop yields, while boosting starch content. © 2017 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.

Characterizing Interdisciplinarity of Researchers and Research Topics Using Web Search Engines

PubMed Central

Sayama, Hiroki; Akaishi, Jin

2012-01-01

Researchers' networks have been subject to active modeling and analysis. Earlier literature mostly focused on citation or co-authorship networks reconstructed from annotated scientific publication databases, which have several limitations. Recently, general-purpose web search engines have also been utilized to collect information about social networks. Here we reconstructed, using web search engines, a network representing the relatedness of researchers to their peers as well as to various research topics. Relatedness between researchers and research topics was characterized by visibility boost—increase of a researcher's visibility by focusing on a particular topic. It was observed that researchers who had high visibility boosts by the same research topic tended to be close to each other in their network. We calculated correlations between visibility boosts by research topics and researchers' interdisciplinarity at the individual level (diversity of topics related to the researcher) and at the social level (his/her centrality in the researchers' network). We found that visibility boosts by certain research topics were positively correlated with researchers' individual-level interdisciplinarity despite their negative correlations with the general popularity of researchers. It was also found that visibility boosts by network-related topics had positive correlations with researchers' social-level interdisciplinarity. Research topics' correlations with researchers' individual- and social-level interdisciplinarities were found to be nearly independent from each other. These findings suggest that the notion of “interdisciplinarity" of a researcher should be understood as a multi-dimensional concept that should be evaluated using multiple assessment means. PMID:22719935

Sperm kinematics and subpopulational responses during the cryopreservation process in caprine ejaculates.

PubMed

Barbas, J P; Leahy, T; Horta, A E; García-Herreros, M

2018-03-20

Sperm cryopreservation in goats has been a challenge for many years due to the detrimental effects of seminal plasma enzymes produced by the bulbo-urethral glands which catalyse the hydrolysis of lecithins in egg yolk to fatty acids and lysolecithins which are deleterious to spermatozoa. This fact implies to carry out additional processing steps during sperm cryopreservation for seminal plasma removal triggering different sperm responses which may affect sperm functionality. The objective of the present study was to determine specific sperm subpopulation responses in different handling steps during the cryopreservation process by using functional sperm kinematic descriptors in caprine ejaculates. Buck ejaculates (n = 40) were analysed for sperm concentration, viability, morphology and acrosome integrity. Moreover, sperm motility was assessed using a computer-assisted sperm analysis (CASA) system after five different handling steps (fresh sperm, 1st washing, 2nd washing, cooling and frozen-thawed sperm) during a standard cryopreservation protocol for goat semen. The results were analysed using Principal Component Analysis (PCA) and multivariate clustering procedures to establish the relationship between the distribution of the subpopulations found and the functional sperm motility in each step. Except for the 1st and 4th steps, four sperm kinematic subpopulations were observed explaining more than 75% of the variance. Based on velocity and linearity parameters and the subpopulations disclosed, the kinematic response varies among processing steps modifying sperm movement trajectories in a subpopulation-specific and handling step-dependent manner (p < 0.001). The predominant motile subpopulation in freshly ejaculated buck sperm had very fast velocity characteristics and a non-linear trajectory (41.1%). Washing buck sperm twice altered the subpopulation structure as well as cooling which resulted in a dramatic reduction in sperm velocities (p < 0.01). Frozen-thawed spermatozoa showed similar characteristics to cooled sperm except there was a further increase in linearity with a large proportion of sperm attributed to new slow, linear cluster (32.5%). In conclusion, this study confirms the variability and heterogeneity of goat sperm kinematic patterns throughout the cryopreservation process and suggests that the predominant motility pattern (assayed in vitro via CASA) of high quality spermatozoa might be typified by high speed and a non-linear trajectory. The relationships among the number and distribution of sperm subpopulations and the different handling steps were particularlly relevant, specially after the cooling and the post-thawing steps, when effects derived from these critical handling steps were evident and altered drastically the sperm motion patterns. Copyright © 2018 Elsevier Inc. All rights reserved.

Historical and Current U.S. Strategies for Boosting Distributed Generation (Chinese Translation)

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

Lowder, Travis; Schwabe, Paul; Zhou, Ella

2015-08-01

This is the Chinese translation of NREL/TP-6A20-64843. This report seeks to introduce a variety of top-down and bottom-up practices that, in concert with the macro-environment of cost-reduction globally and early adoption in Europe, helped boost the distributed generation photovoltaic market in the United States. These experiences may serve as a reference in China's quest to promote distributed renewable energy.

Design of A Grid Integrated PV System with MPPT Control and Voltage Oriented Controller using MATLAB/PLECES

NASA Astrophysics Data System (ADS)

Soreng, Bineeta; Behera, Pradyumna; Pradhan, Raseswari

2017-08-01

This paper presents model of a grid-integrated photovoltaic array with Maximum Power Point Tracker (MPPT) and voltage oriented controller. The MPPT of the PV array is usually an essential part of PV system as MPPT helps the operating point of the solar array to align its maximum power point. In this model, the MPPT along with a DC-DC converter lets a PV generator to produce continuous power, despite of the measurement conditions. The neutral-point-clamped converter (NPC) with a boost converter raises the voltage from the panels to the DC-link. An LCL-filter smoothens the current ripple caused by the PWM modulation of the grid-side inverter. In addition to the MPPT, the system has two more two controllers, such as voltage controller and a current controller. The voltage control has a PI controller to regulate the PV voltage to optimal level by controlling the amount of current injected into the boost stage. Here, the grid-side converter transfers the power from the DC-link into the grid and maintains the DC-link voltage. Three-phase PV inverters are used for off-grid or designed to create utility frequency AC. The PV system can be connected in series or parallel to get the desired output power. To justify the working of this model, the grid-integrated PV system has been designed in MATLAB/PLECS. The simulation shows the P-V curve of implemented PV Array consisting 4 X 20 modules, reactive, real power, grid voltage and current.

Induction of protective immunity against H1N1 influenza A(H1N1)pdm09 with spray-dried and electron-beam sterilised vaccines in non-human primates.

PubMed

Scherließ, Regina; Ajmera, Ankur; Dennis, Mike; Carroll, Miles W; Altrichter, Jens; Silman, Nigel J; Scholz, Martin; Kemter, Kristina; Marriott, Anthony C

2014-04-17

Currently, the need for cooled storage and the impossibility of terminal sterilisation are major drawbacks in vaccine manufacturing and distribution. To overcome current restrictions a preclinical safety and efficacy study was conducted to evaluate new influenza A vaccine formulations regarding thermal resistance, resistance against irradiation-mediated damage and storage stability. We evaluated the efficacy of novel antigen stabilizing and protecting solutions (SPS) to protect influenza A(H1N1)pdm09 split virus antigen under experimental conditions in vitro and in vivo. Original or SPS re-buffered vaccine (Pandemrix) was spray-dried and terminally sterilised by irradiation with 25 kGy (e-beam). Antigen integrity was monitored by SDS-PAGE, dynamic light scattering, size exclusion chromatography and functional haemagglutination assays. In vitro screening experiments revealed a number of highly stable compositions containing glycyrrhizinic acid (GA) and/or chitosan. The most stable composition was selected for storage tests and in vivo assessment of seroconversion in non-human primates (Macaca fascicularis) using a prime-boost strategy. Redispersed formulations with original adjuvant were administered intramuscularly. Storage data revealed high stability of protected vaccines at 4°C and 25°C, 60% relative humidity, for at least three months. Animals receiving original Pandemrix exhibited expected levels of seroconversion after 21 days (prime) and 48 days (boost) as assessed by haemagglutination inhibition and microneutralisation assays. Animals vaccinated with spray-dried and irradiated Pandemrix failed to exhibit seroconversion after 21 days whereas spray-dried and irradiated, SPS-protected vaccines elicited similar seroconversion levels to those vaccinated with original Pandemrix. Boost immunisation with SPS-protected vaccine resulted in a strong increase in seroconversion but had only minor effects in animals treated with non SPS-protected vaccine. In conclusion, utilising the SPS formulation technology, spray-drying and terminal sterilisation of influenza A(H1N1)pdm09 split virus vaccine is feasible. Findings indicate the potential utility of such formulated vaccines e.g. for needle-free vaccination routes and delivery to countries with uncertain cold chain facilities. Copyright © 2014 Elsevier Ltd. All rights reserved.

Quality of Life in Women Undergoing Breast Irradiation in a Randomized, Controlled Clinical Trial Evaluating Different Tumor Bed Boost Fractionations

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

Finkel, Morgan A.; Cooper, Benjamin T.; Li, Xiaochun

Purpose: To identify differences in breast cancer patient-reported quality of life (QOL) between 2 radiation tumor bed boost dose regimens. Methods and Materials: Four hundred patients with stage 0, I, or II breast cancer who underwent segmental mastectomy with sentinel node biopsy and/or axillary node dissection were treated with either a daily or weekly boost. Patients were treated prone to 40.5 Gy/15 fractions to the whole breast, 5 days per week. Patients were randomized to a concomitant daily boost to the tumor bed of 0.5 Gy, or a weekly boost of 2 Gy on Friday. Patients completed 6 validated QOL survey instruments at baseline,more » last week of treatment (3 weeks), 45-60 days from the completion of radiation treatment, and at 2-year follow-up. Results: There were no statistically significance differences in responses to the 6 QOL instruments between the daily and weekly radiation boost regimens, even after adjustment for important covariates. However, several changes in responses over time occurred in both arms, including worsening functional status, cosmetic status, and breast-specific pain at the end of treatment as compared with before and 45 to 60 days after the conclusion of treatment. Conclusions: Whole-breast, prone intensity modulated radiation has similar outcomes in QOL measures whether given with a daily or weekly boost. This trial has generated the foundation for a current study of weekly versus daily radiation boost in women with early breast cancer in which 3-dimensional conformal radiation is allowed as a prospective stratification factor.« less

Sperm collection by transrectal ultrasound-guided massage of the accessory sex glands is less stressful than electroejaculation without altering sperm characteristics in conscious goat bucks.

PubMed

Abril-Sánchez, Silvia; Freitas-de-Melo, Aline; Beracochea, Florencia; Damián, Juan Pablo; Giriboni, Julia; Santiago-Moreno, Julián; Ungerfeld, Rodolfo

2017-08-01

In anesthetized non-domestic ruminants transrectal ultrasound-guided massage of the accessory sex glands (TUMASG) is an alternative method to collect semen slightly less stressful than electroejaculation (EE). However, some sperm characteristics are better when semen is collected with EE than with TUMASG. As anesthesia reduces the response to stressors, the advantages of TUMASG may be reduced in anesthetized animals, and thus, TUMASG may be even more advantageous in conscious animals. Therefore, the aim of the present study was to compare the stress response and the characteristics of the sperm collected with TUMASG and EE in conscious goat bucks. Semen was collected in 10 bucks with both procedures. During each procedure, the time required for ejaculation, the number of electric pulses applied and the number of vocalizations were recorded. Rectal temperature, heart rate, serum cortisol concentration, biochemical and hematological parameters were measured before and after each procedure. Sperm characteristics [ejaculated volume, sperm concentration, sperm mass motility (scale 0-5), sperm vigor (scale 0-5), the percentages of motile and progressive motile sperm, of sperm vitality, of sperm with plasma membrane integrity, and with acrosome damage and morphological abnormalities] were also determined. Electroejaculation required more electric pulses than TUMASG (P < 0.0001), but TUMASG took more time than EE (P < 0.0001). The EE provoked more vocalizations (P = 0.02) and a greater increase of cortisol concentrations than TUMASG (P = 0.04). Heart rate also tended to be greater with EE than with TUMASG (P = 0.07). The sperm characteristics did not differ between TUMASG and EE. In conclusion, TUMASG was less stressful and probably less painful than EE without affecting the semen quality. Thus, although it required more time, TUMASG is an alternative procedure to decrease the welfare concerns raised by EE in conscious goat bucks. Copyright © 2017 Elsevier Inc. All rights reserved.

Conditional Random Field (CRF)-Boosting: Constructing a Robust Online Hybrid Boosting Multiple Object Tracker Facilitated by CRF Learning

PubMed Central

Yang, Ehwa; Gwak, Jeonghwan; Jeon, Moongu

2017-01-01

Due to the reasonably acceptable performance of state-of-the-art object detectors, tracking-by-detection is a standard strategy for visual multi-object tracking (MOT). In particular, online MOT is more demanding due to its diverse applications in time-critical situations. A main issue of realizing online MOT is how to associate noisy object detection results on a new frame with previously being tracked objects. In this work, we propose a multi-object tracker method called CRF-boosting which utilizes a hybrid data association method based on online hybrid boosting facilitated by a conditional random field (CRF) for establishing online MOT. For data association, learned CRF is used to generate reliable low-level tracklets and then these are used as the input of the hybrid boosting. To do so, while existing data association methods based on boosting algorithms have the necessity of training data having ground truth information to improve robustness, CRF-boosting ensures sufficient robustness without such information due to the synergetic cascaded learning procedure. Further, a hierarchical feature association framework is adopted to further improve MOT accuracy. From experimental results on public datasets, we could conclude that the benefit of proposed hybrid approach compared to the other competitive MOT systems is noticeable. PMID:28304366

Levodopa enhances explicit new-word learning in healthy adults: a preliminary study.

PubMed

Shellshear, Leanne; MacDonald, Anna D; Mahoney, Jeffrey; Finch, Emma; McMahon, Katie; Silburn, Peter; Nathan, Pradeep J; Copland, David A

2015-09-01

While the role of dopamine in modulating executive function, working memory and associative learning has been established; its role in word learning and language processing more generally is not clear. This preliminary study investigated the impact of increased synaptic dopamine levels on new-word learning ability in healthy young adults using an explicit learning paradigm. A double-blind, placebo-controlled, between-groups design was used. Participants completed five learning sessions over 1 week with levodopa or placebo administered at each session (five doses, 100 mg). Each session involved a study phase followed by a test phase. Test phases involved recall and recognition tests of the new (non-word) names previously paired with unfamiliar objects (half with semantic descriptions) during the study phase. The levodopa group showed superior recall accuracy for new words over five learning sessions compared with the placebo group and better recognition accuracy at a 1-month follow-up for words learnt with a semantic description. These findings suggest that dopamine boosts initial lexical acquisition and enhances longer-term consolidation of words learnt with semantic information, consistent with dopaminergic enhancement of semantic salience. Copyright © 2015 John Wiley & Sons, Ltd.

Do Acting out Verbs with Dolls and Comparison Learning between Scenes Boost Toddlers' Verb Comprehension?

ERIC Educational Resources Information Center

Schwarz, Amy Louise; Van Kleeck, Anne; Maguire, Mandy J.; Abdi, Herve

2017-01-01

To better understand how toddlers integrate multiple learning strategies to acquire verbs, we compared sensorimotor recruitment and comparison learning because both strategies are thought to boost children's access to scene-level information. For sensorimotor recruitment, we tested having toddlers use dolls as agents and compared this strategy…

Self-affirmation improves self-control over snacking among participants low in eating self-efficacy.

PubMed

Churchill, Susan; Jessop, Donna C; Green, Ricky; Harris, Peter R

2018-04-01

Individuals low in eating self-efficacy are at particular risk of engaging in unhealthy eating behaviours, including the consumption of high calorie snacks. The elevated levels of snacking displayed by these individuals can largely be attributed to their experiencing low self-control over the avoidance of such foods (Hankonen, Kinnunen, Absetz, & Jallinoja, 2014). Interventions are thus required to boost self-control over snacking among those low in eating self-efficacy. Self-affirmation has been shown to boost self-control among individuals with depleted resources in other domains (Schmeichel & Vohs, 2009). The purpose of the current study was to test the hypothesis that a self-affirmation manipulation would similarly increase self-control over snacking for individuals low in eating self-efficacy. At baseline, participants (N = 70) completed measures of dietary restraint and eating self-efficacy. In the main study, participants completed either a self-affirmation or a control task immediately before undertaking a joystick category judgment task that assessed self-control over snacking. Hierarchical multiple regression analysis revealed the predicted significant interaction between eating self-efficacy and self-affirmation, demonstrating that self-affirmation moderated the association between eating self-efficacy and self-control over snacking. Johnson-Neyman regions of significance confirmed that for participants low in eating self-efficacy the self-affirmation manipulation resulted in higher levels of self-control. Unexpectedly, however, for participants high in eating self-efficacy the self-affirmation manipulation was found to be associated with lower levels of self-control. Findings supported the hypothesis that a self-affirmation manipulation would boost self-control over snacking among individuals low in eating self-efficacy. Self-affirmation may thus provide a useful technique for strengthening self-control in relation to the avoidance of unhealthy foods among individuals who find it difficult to manage challenging dietary situations. Copyright © 2018 Elsevier Ltd. All rights reserved.

Fc Receptor-Mediated Activities of Env-Specific Human Monoclonal Antibodies Generated from Volunteers Receiving the DNA Prime-Protein Boost HIV Vaccine DP6-001.

PubMed

Costa, Matthew R; Pollara, Justin; Edwards, Regina Whitney; Seaman, Michael S; Gorny, Miroslaw K; Montefiori, David C; Liao, Hua-Xin; Ferrari, Guido; Lu, Shan; Wang, Shixia

2016-11-15

HIV-1 is able to elicit broadly potent neutralizing antibodies in a very small subset of individuals only after several years of infection, and therefore, vaccines that elicit these types of antibodies have been difficult to design. The RV144 trial showed that moderate protection is possible and that this protection may correlate with antibody-dependent cellular cytotoxicity (ADCC) activity. Our previous studies demonstrated that in an HIV vaccine phase I trial, the DP6-001 trial, a polyvalent Env DNA prime-protein boost formulation could elicit potent and broadly reactive, gp120-specific antibodies with positive neutralization activities. Here we report on the production and analysis of HIV-1 Env-specific human monoclonal antibodies (hMAbs) isolated from vaccinees in the DP6-001 trial. For this initial report, 13 hMAbs from four vaccinees in the DP6-001 trial showed broad binding to gp120 proteins of diverse subtypes both autologous and heterologous to vaccine immunogens. Equally cross-reactive Fc receptor-mediated functional activities, including ADCC and antibody-dependent cellular phagocytosis (ADCP) activities, were present with both immune sera and isolated MAbs, confirming the induction of nonneutralizing functional hMAbs by the DNA prime-protein boost vaccination. Elicitation of broadly reactive hMAbs by vaccination in healthy human volunteers confirms the value of the polyvalent formulation in this HIV vaccine design. The roles of Fc receptor-mediated protective antibody responses are gaining more attention due to their potential contribution to the low-level protection against HIV-1 infection that they provided in the RV144 trial. At the same time, information about hMabs from other human HIV vaccine studies is very limited. In the current study, both immune sera and monoclonal antibodies from vaccinated humans showed not only high-level ADCC and ADCP activities but also cross-subtype ADCC and ADCP activities when a polyvalent DNA prime-protein boost vaccine formulation was used. Copyright © 2016, American Society for Microbiology. All Rights Reserved.

Boosted protease inhibitor monotherapy in HIV-infected adults: outputs from a pan-European expert panel meeting

PubMed Central

2013-01-01

While the introduction of combination highly active antiretroviral therapy (HAART) regimens represents an important advance in the management of human immunodeficiency virus (HIV)-infected patients, tolerability can be an issue and the use of several different agents may produce problems. The switch of combination HAART to ritonavir-boosted protease inhibitor (PI) monotherapy may offer the opportunity to maintain antiviral efficacy while reducing treatment complexity and the risks of toxicity. Current European AIDS Clinical Society (EACS) guidelines recognise ritonavir-boosted PI monotherapy with twice-daily lopinavir/ritonavir or once-daily darunavir/ritonavir as a possible option in patients who have intolerance to nucleoside reverse transcriptase inhibitors, or for treatment simplification. Clinical trials data for PI boosted monotherapy are encouraging, showing substantial efficacy in the majority of patients; however, further data are required before this approach can be recommended as a routine treatment. Available data indicate that the most suitable candidates for the use of boosted PI monotherapy are long-term virologically suppressed patients who have demonstrated good adherence to antiretroviral therapy, who do not have chronic hepatitis B, have no history of treatment failure on PIs and are able to tolerate low-dose ritonavir. PMID:23347595

Streamlining the Design-to-Build Transition with Build-Optimization Software Tools.

PubMed

Oberortner, Ernst; Cheng, Jan-Fang; Hillson, Nathan J; Deutsch, Samuel

2017-03-17

Scaling-up capabilities for the design, build, and test of synthetic biology constructs holds great promise for the development of new applications in fuels, chemical production, or cellular-behavior engineering. Construct design is an essential component in this process; however, not every designed DNA sequence can be readily manufactured, even using state-of-the-art DNA synthesis methods. Current biological computer-aided design and manufacture tools (bioCAD/CAM) do not adequately consider the limitations of DNA synthesis technologies when generating their outputs. Designed sequences that violate DNA synthesis constraints may require substantial sequence redesign or lead to price-premiums and temporal delays, which adversely impact the efficiency of the DNA manufacturing process. We have developed a suite of build-optimization software tools (BOOST) to streamline the design-build transition in synthetic biology engineering workflows. BOOST incorporates knowledge of DNA synthesis success determinants into the design process to output ready-to-build sequences, preempting the need for sequence redesign. The BOOST web application is available at https://boost.jgi.doe.gov and its Application Program Interfaces (API) enable integration into automated, customized DNA design processes. The herein presented results highlight the effectiveness of BOOST in reducing DNA synthesis costs and timelines.

Heterologous Prime-Boost HIV-1 Vaccination Regimens in Pre-Clinical and Clinical Trials

PubMed Central

Brown, Scott A.; Surman, Sherri L.; Sealy, Robert; Jones, Bart G.; Slobod, Karen S.; Branum, Kristen; Lockey, Timothy D.; Howlett, Nanna; Freiden, Pamela; Flynn, Patricia; Hurwitz, Julia L.

2010-01-01

Currently, there are more than 30 million people infected with HIV-1 and thousands more are infected each day. Vaccination is the single most effective mechanism for prevention of viral disease, and after more than 25 years of research, one vaccine has shown somewhat encouraging results in an advanced clinical efficacy trial. A modified intent-to-treat analysis of trial results showed that infection was approximately 30% lower in the vaccine group compared to the placebo group. The vaccine was administered using a heterologous prime-boost regimen in which both target antigens and delivery vehicles were changed during the course of inoculations. Here we examine the complexity of heterologous prime-boost immunizations. We show that the use of different delivery vehicles in prime and boost inoculations can help to avert the inhibitory effects caused by vector-specific immune responses. We also show that the introduction of new antigens into boost inoculations can be advantageous, demonstrating that the effect of ‘original antigenic sin’ is not absolute. Pre-clinical and clinical studies are reviewed, including our own work with a three-vector vaccination regimen using recombinant DNA, virus (Sendai virus or vaccinia virus) and protein. Promising preliminary results suggest that the heterologous prime-boost strategy may possibly provide a foundation for the future prevention of HIV-1 infections in humans. PMID:20407589

Tracking down hyper-boosted top quarks

DOE PAGES

Larkoski, Andrew J.; Maltoni, Fabio; Selvaggi, Michele

2015-06-05

The identification of hadronically decaying heavy states, such as vector bosons, the Higgs, or the top quark, produced with large transverse boosts has been and will continue to be a central focus of the jet physics program at the Large Hadron Collider (LHC). At a future hadron collider working at an order-of-magnitude larger energy than the LHC, these heavy states would be easily produced with transverse boosts of several TeV. At these energies, their decay products will be separated by angular scales comparable to individual calorimeter cells, making the current jet substructure identification techniques for hadronic decay modes not directlymore » employable. In addition, at the high energy and luminosity projected at a future hadron collider, there will be numerous sources for contamination including initial- and final-state radiation, underlying event, or pile-up which must be mitigated. We propose a simple strategy to tag such "hyper-boosted" objects that defines jets with radii that scale inversely proportional to their transverse boost and combines the standard calorimetric information with charged track-based observables. By means of a fast detector simulation, we apply it to top quark identification and demonstrate that our method efficiently discriminates hadronically decaying top quarks from light QCD jets up to transverse boosts of 20 TeV. Lastly, our results open the way to tagging heavy objects with energies in the multi-TeV range at present and future hadron colliders.« less

Research of digital controlled DC/DC converter based on STC12C5410AD

NASA Astrophysics Data System (ADS)

Chen, Dan-Jiang; Jin, Xin; Xiao, Zhi-Hong

2010-02-01

In order to study application of digital control technology on DC/DC converter, principle of increment mode PID control algorithm was analyzed in the paper. Then, a SCM named STC12C5410AD was introduced with its internal resources and characteristics. The PID control algorithm can be implemented easily based on it. The output of PID control was used to change the value of a variable that is 255 times than duty cycle, and this reduced the error of calculation. The valid of the presented algorithm was verified by an experiment for a BUCK DC/DC converter. The experimental results indicated that output voltage of the BUCK converter is stable with low ripple.

Low-temperature operation of a Buck DC/DC converter

NASA Technical Reports Server (NTRS)

Ray, Biswajit; Gerber, Scott S.; Patterson, Richard L.; Myers, Ira T.

1995-01-01

Low-temperature (77 K) operation of a 42/28 V, 175 W, 50 kHz PWM Buck DC/DC converter designed with commercially available components is reported. Overall, the converter losses decreased at 77 K compared to room temperature operation. A full-load efficiency of 97 percent was recorded at liquid-nitrogen temperature, compared to 95.8 percent at room temperature. Power MOSFET operation improved significantly where as the output rectifier operation deteriorated at low-temperature. The performance of the output filter inductor and capacitor did not change significantly at 77 K compared to room temperature performance. It is possible to achieve high-density and high efficiency power conversion at low-temperatures due to improved electronic, electrical and thermal properties of materials.

An Advanced Photovoltaic Array Regulator Module

NASA Technical Reports Server (NTRS)

Button, Robert M.

1996-01-01

Current trends in satellite design are focused on developing small, reliable, and inexpensive spacecraft. To that end, a modular power management and distribution system is proposed which will help transition the aerospace industry towards an assembly line approach to building spacecraft. The modular system is based on an innovative DC voltage boost converter called the Series Connected Boost Unit (SCBU). The SCBU uses any isolating DC-DC converter and adds a unique series connection. This simple modification provides the SCBU topology with many advantages over existing boost converters. Efficiencies of 94-98%, power densities above 1,000 W/kg, and inherent fault tolerance are just a few of the characteristics presented. Limitations of the SCBU technology are presented, and it is shown that the SCBU makes an ideal photovoltaic an-ay regulator. A set of photovoltaic power system requirements are presented that can be applied to almost any low Earth orbit satellite. Finally, a modular design based on the series connected boost unit is outlined and functional descriptions of the components are given.

A novel power converter for photovoltaic applications

NASA Astrophysics Data System (ADS)

Yuvarajan, S.; Yu, Dachuan; Xu, Shanguang

A simple and economical power conditioner to convert the power available from solar panels into 60 Hz ac voltage is described. The raw dc voltage from the solar panels is converted to a regulated dc voltage using a boost converter and a large capacitor and the dc output is then converted to 60 Hz ac using a bridge inverter. The ratio between the load current and the short-circuit current of a PV panel at maximum power point is nearly constant for different insolation (light) levels and this property is utilized in designing a simple maximum power point tracking (MPPT) controller. The controller includes a novel arrangement for sensing the short-circuit current without disturbing the operation of the PV panel and implementing MPPT. The switching losses in the inverter are reduced by using snubbers. The results obtained on an experimental converter are presented.

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

Jabbari, Siavash; Weinberg, Vivian K.; Kaprealian, Tania

Purpose: High dose rate (HDR) brachytherapy has been established as an excellent monotherapy or after external-beam radiotherapy (EBRT) boost treatment for prostate cancer (PCa). Recently, dosimetric studies have demonstrated the potential for achieving similar dosimetry with stereotactic body radiotherapy (SBRT) compared with HDR brachytherapy. Here, we report our technique, PSA nadir, and acute and late toxicity with SBRT as monotherapy and post-EBRT boost for PCa using HDR brachytherapy fractionation. Patients and Methods: To date, 38 patients have been treated with SBRT at University of California-San Francisco with a minimum follow-up of 12 months. Twenty of 38 patients were treated withmore » SBRT monotherapy (9.5 Gy Multiplication-Sign 4 fractions), and 18 were treated with SBRT boost (9.5 Gy Multiplication-Sign 2 fractions) post-EBRT and androgen deprivation therapy. PSA nadir to date for 44 HDR brachytherapy boost patients with disease characteristics similar to the SBRT boost cohort was also analyzed as a descriptive comparison. Results: SBRT was well tolerated. With a median follow-up of 18.3 months (range, 12.6-43.5), 42% and 11% of patients had acute Grade 2 gastrourinary and gastrointestinal toxicity, respectively, with no Grade 3 or higher acute toxicity to date. Two patients experienced late Grade 3 GU toxicity. All patients are without evidence of biochemical or clinical progression to date, and favorably low PSA nadirs have been observed with a current median PSA nadir of 0.35 ng/mL (range, <0.01-2.1) for all patients (0.47 ng/mL, range, 0.2-2.1 for the monotherapy cohort; 0.10 ng/mL, range, 0.01-0.5 for the boost cohort). With a median follow-up of 48.6 months (range, 16.4-87.8), the comparable HDR brachytherapy boost cohort has achieved a median PSA nadir of 0.09 ng/mL (range, 0.0-3.3). Conclusions: Early results with SBRT monotherapy and post-EBRT boost for PCa demonstrate acceptable PSA response and minimal toxicity. PSA nadir with SBRT boost appears comparable to those achieved with HDR brachytherapy boost.« less

Combined prime-boost vaccination against tick-borne encephalitis (TBE) using a recombinant vaccinia virus and a bacterial plasmid both expressing TBE virus non-structural NS1 protein

PubMed Central

Aleshin, SE; Timofeev, AV; Khoretonenko, MV; Zakharova, LG; Pashvykina, GV; Stephenson, JR; Shneider, AM; Altstein, AD

2005-01-01

Background Heterologous prime-boost immunization protocols using different gene expression systems have proven to be successful tools in protecting against various diseases in experimental animal models. The main reason for using this approach is to exploit the ability of expression cassettes to prime or boost the immune system in different ways during vaccination procedures. The purpose of the project was to study the ability of recombinant vaccinia virus (VV) and bacterial plasmid, both carrying the NS1 gene from tick-borne encephalitis (TBE) virus under the control of different promoters, to protect mice against lethal challenge using a heterologous prime-boost vaccination protocol. Results The heterologous prime-boost vaccination protocol, using a VV recombinant and bacterial plasmid, both containing the NS1 TBE virus protein gene under the control of different promoters, achieved a high level of protection in mice against lethal challenge with a highly pathogenic TBE virus strain. No signs of pronounced TBE infection were detected in the surviving animals. Conclusion Heterologous prime-boost vaccination protocols using recombinant VV and bacterial plasmids could be used for the development of flavivirus vaccines. PMID:16076390

New clinical trial tests prime-and-boost vaccine delivery for advanced solid tumors | Center for Cancer Research

Cancer.gov

Researchers are testing a prime-and-boost approach to safely direct the immune system to kill tumor cells that express brachyury, a protein expressed in high levels in some cancers. A new clinical trial is testing an experimental vaccine in patients whose cancers have not responded to standard treatments.

Electromyography comparison of the effects of various footwear in the activity patterns of the peroneus longus and brevis muscles.

PubMed

Roca-Dols, Andrea; Losa-Iglesias, Marta Elena; Sánchez-Gómez, Rubén; López-López, Daniel; Becerro-de-Bengoa-Vallejo, Ricardo; Calvo-Lobo, César

2018-06-01

Peroneus longus and brevis (PLB) disorders are commonly in people with lateral ligamentous instability, ankle pain, lateral hindfoot pain and structures of the proximal compartment of the lower legs and their muscle activity is believed to be influenced by different footwear types. The proposal of this research is to evaluate the effects of five types of footwear with respect to the barefoot condition and analyze the activity patterns of PLB muscles in healthy subjects during the gait cycle. Thirty healthy subjects were recruited in a laboratory in this cross-sectional research design. While walking, electromyography (EMG) activity was measured from PLB via surface electrodes in six experimental conditions: 1) barefoot, 2) minimalist, 3) pronated control, 4) air chamber, 5) ethyl-vinyl-acetate (EVA) and 6) boost. These data were obtained and compared. The peroneus brevis showed significant reductions in the peak amplitude of the five footwear types (minimalist, pronation control, air chamber, EVA and boost) with respect to the barefoot condition in the propulsion phase of the gait cycle during walking (P = 0.034; P < 0.001; P < 0.001; P < 0.001; P = 0.006) and running (P = 0.004; P < 0.001; P = 0.001; P < 0.001; P = 0.001), respectively. Furthermore, peroneus longus showed significant reductions in the peak amplitude of these five footwear types with respect to the barefoot condition in the propulsion phase of the gait cycle during running (P = 0.005; P = 0.038; P = 0.019; P = 0.025; P = 0.021). The EMG activity patterns of the PLB muscles may depend on the use of different types of sport shoes such as minimalist, pronation control, air chamber, EVA and boost footwear with respect the barefoot condition in different phases of the gait cycle during walking and running. Copyright © 2018 Elsevier Ltd. All rights reserved.

Adaptive fractional order sliding mode control for Boost converter in the Battery/Supercapacitor HESS.

PubMed

Wang, Jianlin; Xu, Dan; Zhou, Huan; Zhou, Tao

2018-01-01

In this paper, an adaptive fractional order sliding mode control (AFSMC) scheme is designed for the current tracking control of the Boost-type converter in a Battery/Supercapacitor hybrid energy storage system (HESS). In order to stabilize the current, the adaptation rules based on state-observer and Lyapunov function are being designed. A fractional order sliding surface function is defined based on the tracking current error and adaptive rules. Furthermore, through fractional order analysis, the stability of the fractional order control system is proven, and the value of the fractional order (λ) is being investigated. In addition, the effectiveness of the proposed AFSMC strategy is being verified by numerical simulations. The advantages of good transient response and robustness to uncertainty are being indicated by this design, when compared with a conventional integer order sliding mode control system.

Bridgeless SEPIC PFC Converter for Multistring LED Driver

NASA Astrophysics Data System (ADS)

Jha, Aman; Singh, Bhim

2018-05-01

This paper deals with Power Factor Correction (PFC) in Low Voltage High Current (LVHC) multi-string light emitting diode (LED) using a bridgeless (BL) single ended primary inductance converter (SEPIC). This application is designed for large area LED lighting with illumination control. A multi-mode LED dimming technique is used for the lighting control. The BL-SEPIC PFC converter is used as a load emulator for high power factor. The regulated low voltage from flyback converter is a source power to the synchronous buck converters for multi-string LED driver and forced cooling system for LED junction. The BL-SEPIC PFC converter inductor design is based on Discontinuous Inductor Current Modes (DICM) which provides good PFC at low cost. Test results are found quite satisfactory for universal input AC (90-265 V). There is significant improvement in the power factor and input current Total Harmonic Distortion (THD) with good margin of harmonic limits for lighting IEC 61000-3-2 Class C.

Trak Investigation of Focusing Electrode Geometries for the DARHT Axis-I Diode

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

Kallas, Nicholas Dimitrious

2017-05-15

An investigation was carried out on the effects of different cathode shroud geometries of the DARHT Axis-1 diode using the Trak ray tracing software. Pierce angles of 20, 30, 45, 60, and 67.5 degrees were investigated. For each geometry the current density with respect to radial position will be presented as it evolves in the longitudinal direction. In addition the emittances for each geometry are compared and this information is used to determine the optimal geometry from the selected angles. These results are compared to the baseline geometry currently employed at DARHT of a simple 2.5mm recessed velvet cathode. Ofmore » the selected angles it was found that 45 degrees produced the lowest normalized emittance value, whereas 60 degrees produced the most uniform current density profile at 1cm away from the emission surface. For the purpose of this investigation the effects of the bucking coil and solenoid around the hollow anode of the DARHT Axis I injector are neglected.« less

Fuzzy Logic Controlled Solar Module for Driving Three- Phase Induction Motor

NASA Astrophysics Data System (ADS)

Afiqah Zainal, Nurul; Sooi Tat, Chan; Ajisman

2016-02-01

Renewable energy produced by solar module gives advantages for generated three- phase induction motor in remote area. But, solar module's ou tput is uncertain and complex. Fuzzy logic controller is one of controllers that can handle non-linear system and maximum power of solar module. Fuzzy logic controller used for Maximum Power Point Tracking (MPPT) technique to control Pulse-Width Modulation (PWM) for switching power electronics circuit. DC-DC boost converter used to boost up photovoltaic voltage to desired output and supply voltage source inverter which controlled by three-phase PWM generated by microcontroller. IGBT switched Voltage source inverter (VSI) produced alternating current (AC) voltage from direct current (DC) source to control speed of three-phase induction motor from boost converter output. Results showed that, the output power of solar module is optimized and controlled by using fuzzy logic controller. Besides that, the three-phase induction motor can be drive and control using VSI switching by the PWM signal generated by the fuzzy logic controller. This concluded that the non-linear system can be controlled and used in driving three-phase induction motor.

Intranasal mucosal boosting with an adenovirus-vectored vaccine markedly enhances the protection of BCG-primed guinea pigs against pulmonary tuberculosis.

PubMed

Xing, Zhou; McFarland, Christine T; Sallenave, Jean-Michel; Izzo, Angelo; Wang, Jun; McMurray, David N

2009-06-10

Recombinant adenovirus-vectored (Ad) tuberculosis (TB) vaccine platform has demonstrated great potential to be used either as a stand-alone or a boost vaccine in murine models. However, Ad TB vaccine remains to be evaluated in a more relevant and sensitive guinea pig model of pulmonary TB. Many vaccine candidates shown to be effective in murine models have subsequently failed to pass the test in guinea pig models. Specific pathogen-free guinea pigs were immunized with BCG, AdAg85A intranasally (i.n), AdAg85A intramuscularly (i.m), BCG boosted with AdAg85A i.n, BCG boosted with AdAg85A i.m, or treated only with saline. The animals were then infected by a low-dose aerosol of M. tuberculosis (M.tb). At the specified times, the animals were sacrificed and the levels of infection in the lung and spleen were assessed. In separate studies, the long-term disease outcome of infected animals was monitored until the termination of this study. Immunization with Ad vaccine alone had minimal beneficial effects. Immunization with BCG alone and BCG prime-Ad vaccine boost regimens significantly reduced the level of M.tb infection in the tissues to a similar extent. However, while BCG alone prolonged the survival of infected guinea pigs, the majority of BCG-immunized animals succumbed by 53 weeks post-M.tb challenge. In contrast, intranasal or intramuscular Ad vaccine boosting of BCG-primed animals markedly improved the survival rate with 60% of BCG/Ad i.n- and 40% of BCG/Ad i.m-immunized guinea pigs still surviving by 74 weeks post-aerosol challenge. Boosting, particularly via the intranasal mucosal route, with AdAg85A vaccine is able to significantly enhance the long-term survival of BCG-primed guinea pigs following pulmonary M.tb challenge. Our results thus support further evaluation of this viral-vectored TB vaccine in clinical trials.

Long-term T-cell-mediated immunologic memory to hepatitis B vaccine in young adults following neonatal vaccination.

PubMed

Saffar, Hiva; Saffar, Mohammed Jafar; Ajami, Abolghasem; Khalilian, Ali Reza; Shams-Esfandabad, Kian; Mirabi, Araz Mohammad

2014-09-01

The long-term duration of cell-mediated immunity induced by neonatal hepatitis B virus (HBV) vaccination is unknown. Study was designed to determine the cellular immunity memory status among young adults twenty years after infantile HB immunization. Study subjects were party selected from a recent seroepidemiologic study in young adults, who had been vaccinated against HBV twenty years earlier. Just before and ten to 14 days after one dose of HBV vaccine booster injection, blood samples were obtained and sera concentration of cytokines (interleukin 2 and interferon) was measured. More than twofold increase after boosting was considered positive immune response. With regard to the serum level of antibody against HBV surface antigen (HBsAb) before boosting, the subjects were divided into four groups as follow: GI, HBsAb titer < 2; GII, titer 2 to 9.9; GIII, titer 10 to 99; and GIV, titers ≥ 100 IU/L. Mean concentration level (MCL) of each cytokines for each group at preboosting and postboosting and the proportion of responders in each groups were determined. Paired descriptive statistical analysis method (t test) was used to compare the MCL of each cytokines in each and between groups and the frequency of responders in each group. Before boosting, among 176 boosted individuals, 75 (42.6%) had HBsAb 10 IU/L and were considered seroprotected. Among 101 serosusceptible persons, more than 80% of boosted individuals showed more than twofold increase in cytokines concentration, which meant positive HBsAg-specific cell-mediated immunity. MCL of both cytokines after boosting in GIV were decreased more than twofold, possibly because of recent natural boosting. Findings showed that neonatal HBV immunization was efficacious in inducing long-term immunity and cell-mediated immune memory for up to two decades, and booster vaccination are not required. Further monitoring of vaccinated subjects for HBV infections are recommended.

Three-Year Durability of Immune Responses Induced by HIV-DNA and HIV-Modified Vaccinia Virus Ankara and Effect of a Late HIV-Modified Vaccinia Virus Ankara Boost in Tanzanian Volunteers.

PubMed

Joachim, Agricola; Munseri, Patricia J; Nilsson, Charlotta; Bakari, Muhammad; Aboud, Said; Lyamuya, Eligius F; Tecleab, Teghesti; Liakina, Valentina; Scarlatti, Gabriella; Robb, Merlin L; Earl, Patricia L; Moss, Bernard; Wahren, Britta; Mhalu, Fred; Ferrari, Guido; Sandstrom, Eric; Biberfeld, Gunnel

2017-08-01

We explored the duration of immune responses and the effect of a late third HIV-modified vaccinia virus Ankara (MVA) boost in HIV-DNA primed and HIV-MVA boosted Tanzanian volunteers. Twenty volunteers who had previously received three HIV-DNA and two HIV-MVA immunizations were given a third HIV-MVA immunization 3 years after the second HIV-MVA boost. At the time of the third HIV-MVA, 90% of the vaccinees had antibodies to HIV-1 subtype C gp140 (median titer 200) and 85% to subtype B gp160 (median titer 100). The majority of vaccinees had detectable antibody-dependent cellular cytotoxicity (ADCC)-mediating antibodies, 70% against CRF01_AE virus-infected cells (median titer 239) and 84% against CRF01_AE gp120-coated cells (median titer 499). A high proportion (74%) of vaccinees had IFN-γ ELISpot responses, 63% to Gag and 42% to Env, 3 years after the second HIV-MVA boost. After the third HIV-MVA, there was an increase in Env-binding antibodies and ADCC-mediating antibodies relative to the response seen at the time of the third HIV-MVA vaccination, p < .0001 and p < .05, respectively. The frequency of IFN-γ ELISpot responses increased to 95% against Gag or Env and 90% to both Gag and Env, p = .064 and p = .002, respectively. In conclusion, the HIV-DNA prime/HIV-MVA boost regimen elicited potent antibody and cellular immune responses with remarkable durability, and a third HIV-MVA immunization significantly boosted both antibody and cellular immune responses relative to the levels detected at the time of the third HIV-MVA, but not to higher levels than after the second HIV-MVA.

Effect of priming/booster immunisation protocols on immune response to canine parvovirus peptide induced by vaccination with a chimaeric plant virus construct.

PubMed

Nicholas, B L; Brennan, F R; Hamilton, W D O; Wakelin, D

2003-06-02

Expression of a 17-mer peptide sequence from canine parvovirus expressed on cowpea mosaic virus (CPMV) to form chimaeric virus particles (CVPs) creates vaccine antigens that elicit strong anti-peptide immune responses in mice. Systemic (subcutaneous, s.c.) immunisation and boosting with such CVP constructs produces IgG(2a) serum antibody responses, while mucosal (intranasal, i.n.) immunisation and boosting elicits intestinal IgA responses. Combinations of systemic and mucosal routes for priming and boosting immunisations were used to examine their influence on the level, type and location of immune response generated to one of these constructs (CVP-1). In all cases, s.c. administration, whether for immunisation or boosting, generated a Th1-biased response, reflected in a predominantly IgG(2a) serum antibody isotype and secretion of IFN-gamma from in vitro-stimulated lymphocytes. Serum antibody responses were greatest in animals primed and boosted subcutaneously, and least in mucosally vaccinated mice. The i.n. exposure also led to IFN-gamma release from in vitro-stimulated cells, but serum IgG(2a) was significantly elevated only in mice primed intranasally and boosted subcutaneously. Peptide- and wild-type CPMV-specific IgA responses in gut lavage fluid were greatest in animals exposed mucosally and least in those primed and boosted subcutaneously or primed subcutaneously and boosted orally. Lymphocytes from immunised mice proliferated in response to in vitro stimulation with CPMV but not with peptide. The predominant secretion of IFN-gamma from all immunising/boosting combinations indicates that the route of vaccination and challenge does not alter the Th1 bias of the response to CVP constructs. However, optimal serum and intestinal antibody responses were achieved by combining s.c. and i.n. administration.

Control of Grid Connected Photovoltaic System Using Three-Level T-Type Inverter

NASA Astrophysics Data System (ADS)

Zorig, Abdelmalik; Belkeiri, Mohammed; Barkat, Said; Rabhi, Abdelhamid

2016-08-01

Three-level T-Type inverter (3LT2I) topology has numerous advantageous compared to three-level neutral-point-clamped (NPC) inverter. The main benefits of 3LT2I inverter are the efficiency, inverter cost, switching losses, and the quality of output voltage waveforms. In this paper, a photovoltaic distributed generation system based on dual-stage topology of DC-DC boost converter and 3LT2I is introduced. To that end, a decoupling control strategy of 3LT2I is proposed to control the current injected into the grid, reactive power compensation, and DC-link voltage. The resulting system is able to extract the maximum power from photovoltaic generator, to achieve sinusoidal grid currents, and to ensure reactive power compensation. The voltage-balancing control of two split DC capacitors of the 3LT2I is achieved using three-level space vector modulation with balancing strategy based on the effective use of the redundant switching states of the inverter voltage vectors. The proposed system performance is investigated at different operating conditions.

Five-year Results of Whole Breast Intensity Modulated Radiation Therapy for the Treatment of Early Stage Breast Cancer: The Fox Chase Cancer Center Experience

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

Keller, Lanea M.M., E-mail: Lanea.Keller@fccc.edu; Sopka, Dennis M.; Li Tianyu

Purpose: To report the 5-year outcomes using whole-breast intensity-modulated radiation therapy (IMRT) for the treatment of early-stage-breast cancer at the Fox Chase Cancer Center. Methods and Materials: A total of 946 women with early-stage breast cancer (stage 0, I, or II) were treated with IMRT after surgery with or without systemic therapy from 2003-2010. Whole-breast radiation was delivered via an IMRT technique with a median whole-breast radiation dose of 46 Gy and median tumor bed boost of 14 Gy. Endpoints included local-regional recurrence, cosmesis, and late complications. Results: With a median follow-up of 31 months (range, 1-97 months), there weremore » 12 ipsilateral breast tumor recurrences (IBTR) and one locoregional recurrence. The 5-year actuarial IBTR and locoregional recurrence rates were 2.0% and 2.4%. Physician-reported cosmestic outcomes were available for 645 patients: 63% were considered 'excellent', 33% 'good', and <1.5% 'fair/poor'. For physician-reported cosmesis, boost doses {>=}16 Gy, breast size >900 cc, or boost volumes >34 cc were significantly associated with a 'fair/poor' cosmetic outcome. Fibrosis, edema, erythema, and telangectasia were also associated with 'fair/poor' physician-reported cosmesis; erythema and telangectasia remained significant on multivariate analysis. Patient-reported cosmesis was available for 548 patients, and 33%, 50%, and 17% of patients reported 'excellent', 'good', and 'fair/poor' cosmesis, respectively. The use of a boost and increased boost volume: breast volume ratio were significantly associated with 'fair/poor' outcomes. No parameter for patient-reported cosmesis was significant on multivariate analysis. The chances of experiencing a treatment related effect was significantly associated with a boost dose {>=}16 Gy, receipt of chemotherapy and endocrine therapy, large breast size, and electron boost energy. Conclusions: Whole-breast IMRT is associated with very low rates of local recurrence at 5 years, 83%-98% 'good/excellent' cosmetic outcomes, and minimal chronic toxicity, including late fibrosis.« less

Implementation of Maximum Power Point Tracking (MPPT) Solar Charge Controller using Arduino

NASA Astrophysics Data System (ADS)

Abdelilah, B.; Mouna, A.; KouiderM’Sirdi, N.; El Hossain, A.

2018-05-01

the platform Arduino with a number of sensors standard can be used as components of an electronic system for acquiring measures and controls. This paper presents the design of a low-cost and effective solar charge controller. This system includes several elements such as the solar panel converter DC/DC, battery, circuit MPPT using Microcontroller, sensors, and the MPPT algorithm. The MPPT (Maximum Power Point Tracker) algorithm has been implemented using an Arduino Nano with the preferred program. The voltage and current of the Panel are taken where the program implemented will work and using this algorithm that MPP will be reached. This paper provides details on the solar charge control device at the maximum power point. The results include the change of the duty cycle with the change in load and thus mean the variation of the buck converter output voltage and current controlled by the MPPT algorithm.

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

Chang, David W., E-mail: David.Chang@petermac.org; Marvelde, Luc te; Chua, Boon H.

Purpose: To report the local recurrence rate and late toxicity of intraoperative radiation therapy (IORT) boost to the tumor bed using the Intrabeam System followed by external-beam whole-breast irradiation (WBI) in women with early-stage breast cancer in a prospective single-institution study. Methods and Materials: Women with breast cancer ≤3 cm were recruited between February 2003 and May 2005. After breast-conserving surgery, a single dose of 5 Gy IORT boost was delivered using 50-kV x-rays to a depth of 10 mm from the applicator surface. This was followed by WBI to a total dose of 50 Gy in 25 fractions. Patientsmore » were reviewed at regular, predefined intervals. Late toxicities were recorded using the Radiation Therapy Oncology Group/European Organization for Research and Treatment of Cancer Late Radiation Morbidity Scoring systems. Results: Fifty-five patients completed both IORT boost and external-beam WBI. Median follow-up was 3.3 years (range, 1.4-4.1 years). There was no reported locoregional recurrence or death. One patient developed distant metastases. Grade 2 and 3 subcutaneous fibrosis was detected in 29 (53%) and 8 patients (15%), respectively. Conclusions: The use of IORT as a tumor bed boost using kV x-rays in breast-conserving therapy was associated with good local control but a clinically significant rate of grade 2 and 3 subcutaneous fibrosis.« less

Preliminary Evaluation of a Turbine/Rotary Combustion Compound Engine for a Subsonic Transport. [fuel consumption and engine tests of turbofan engines

NASA Technical Reports Server (NTRS)

Civinskas, K. C.; Kraft, G. A.

1976-01-01

The fuel consumption of a modern compound engine with that of an advanced high pressure ratio turbofan was compared. The compound engine was derived from a turbofan engine by replacing the combustor with a rotary combustion (RC) engine. A number of boost pressure ratios and compression ratios were examined. Cooling of the RC engine was accomplished by heat exchanging to the fan duct. Performance was estimated with an Otto-cycle for two levels of energy lost to cooling. The effects of added complexity on cost and maintainability were not examined and the comparison was solely in terms of cruise performance and weight. Assuming a 25 percent Otto-cycle cooling loss (representative of current experience), the best compound engine gave a 1.2 percent improvement in cruise. Engine weight increased by 23 percent. For a 10 percent Otto-cycle cooling loss (representing advanced insulation/high temperature materials technology), a compound engine with a boost PR of 10 and a compression ratio of 10 gave an 8.1 percent lower cruise than the reference turbofan.

External beam boost versus interstitial high-dose-rate brachytherapy boost in the adjuvant radiotherapy following breast-conserving therapy in early-stage breast cancer: a dosimetric comparison

PubMed Central

Melchert, Corinna; Kovács, György

2016-01-01

Purpose This study aims to compare the dosimetric data of local tumor's bed dose escalation (boost) with photon beams (external beam radiation therapy – EBRT) versus high-dose-rate interstitial brachytherapy (HDR-BT) after breast-conserving treatment in women with early-stage breast cancer. Material and methods We analyzed the treatment planning data of 136 irradiated patients, treated between 2006 and 2013, who underwent breast-conserving surgery and adjuvant whole breast irradiation (WBI; 50.4 Gy) and boost (HDR-BT: 10 Gy in one fraction [n = 36]; EBRT: 10 Gy in five fractions [n = 100]). Organs at risk (OAR; heart, ipsilateral lung, skin, most exposed rib segment) were delineated. Dosimetric parameters were calculated with the aid of dose-volume histograms (DVH). A non-parametric test was performed to compare the two different boost forms. Results There was no difference for left-sided cancers regarding the maximum dose to the heart (HDR-BT 29.8% vs. EBRT 29.95%, p = 0.34). The maximum doses to the other OAR were significantly lower for HDR-BT (Dmax lung 47.12% vs. 87.7%, p < 0.01; rib 61.17% vs. 98.5%, p < 0.01; skin 57.1% vs. 94.75%, p < 0.01; in the case of right-sided breast irradiation, dose of the heart 6.00% vs. 16.75%, p < 0.01). Conclusions Compared to EBRT, local dose escalation with HDR-BT presented a significant dose reduction to the investigated OAR. Only left-sided irradiation showed no difference regarding the maximum dose to the heart. Reducing irradiation exposure to OAR could result in a reduction of long-term side effects. Therefore, from a dosimetric point of view, an interstitial boost complementary to WBI via EBRT seems to be more advantageous in the adjuvant radiotherapy of breast cancer. PMID:27648082

Electrodeposited Nanolaminated CoNiFe Cores for Ultracompact DC-DC Power Conversion

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

Kim, J; Kim, M; Herrault, F

2015-09-01

Laminated metallic alloy cores (i.e., alternating layers of thin film metallic alloy and insulating material) of appropriate lamination thickness enable suppression of eddy current losses at high frequencies. Magnetic cores comprised of many such laminations yield substantial overall magnetic volume, thereby enabling high-power operation. Previously, we reported nanolaminated permalloy (Ni-80 Fe-20) cores based on a sequential electrodeposition technique, demonstrating negligible eddy current losses at peak flux densities up to 0.5 T and operating at megahertz frequencies. This paper demonstrates improved performance of nanolaminated cores comprising tens to hundreds of layers of 300-500-nm-thick CoNiFe films that exhibit superior magnetic properties (e.g.,more » higher saturation flux density and lower coercivity) than permalloy. Nanolaminated CoNiFe cores can be operated up to a peak flux density of 0.9 T, demonstrating improved power handling capacity and exhibiting 30% reduced volumetric core loss, attributed to lowered hysteresis losses compared to the nanolaminated permalloy core of the same geometry. Operating these cores in a buck dc-dc power converter at a switching frequency of 1 MHz, the nanolaminated CoNiFe cores achieved a conversion efficiency exceeding 90% at output power levels up to 7 W, compared to an achieved permalloy core conversion efficiency below 86% at 6 W.« less

Mercury Project

NASA Image and Video Library

1962-02-20

Astronaut John Glenn enters the Mercury spacecraft, Friendship 7, prior to the launch of MA-6 on February 20, 1961 and became the first American who orbited the Earth. The MA-6 mission was the first manned orbital flight boosted by the Mercury-Atlas vehicle, a modified Atlas ICBM (Intercontinental Ballistic Missile), lasted for five hours, and orbited the Earth three times.

Every Moment Counts: Five Principles for Boosting the Achievement of Struggling Students

ERIC Educational Resources Information Center

Gerzon-Kessler, Ari

2006-01-01

In this article, the author relates her difficult experiences as a novice teacher when she started teaching bilingual third-graders in Spanish at Spangler Elementary School in 2002. She relates that her teaching strategy of balancing rigor and sweetness had its rewards as her students' rate of reading proficiency on the Colorado Student Assessment…

Boosting Engagement and Growth with Formative Assessment: Leaders Share Their Lessons

ERIC Educational Resources Information Center

Northwest Evaluation Association, 2016

2016-01-01

Our featured leaders saw big gains when their teachers began using formative assessment practice to guide student growth minute-by-minute. Read the fourth article in our five-part series for the scoop on how committing to this high-impact instructional practice paid off for a regional agency, district, and school. Learn: (1) why our featured…

Simulation, measurement, and emulation of photovoltaic modules using high frequency and high power density power electronic circuits

NASA Astrophysics Data System (ADS)

Erkaya, Yunus

The number of solar photovoltaic (PV) installations is growing exponentially, and to improve the energy yield and the efficiency of PV systems, it is necessary to have correct methods for simulation, measurement, and emulation. PV systems can be simulated using PV models for different configurations and technologies of PV modules. Additionally, different environmental conditions of solar irradiance, temperature, and partial shading can be incorporated in the model to accurately simulate PV systems for any given condition. The electrical measurement of PV systems both prior to and after making electrical connections is important for attaining high efficiency and reliability. Measuring PV modules using a current-voltage (I-V) curve tracer allows the installer to know whether the PV modules are 100% operational. The installed modules can be properly matched to maximize performance. Once installed, the whole system needs to be characterized similarly to detect mismatches, partial shading, or installation damage before energizing the system. This will prevent any reliability issues from the onset and ensure the system efficiency will remain high. A capacitive load is implemented in making I-V curve measurements with the goal of minimizing the curve tracer volume and cost. Additionally, the increase of measurement resolution and accuracy is possible via the use of accurate voltage and current measurement methods and accurate PV models to translate the curves to standard testing conditions. A move from mechanical relays to solid-state MOSFETs improved system reliability while significantly reducing device volume and costs. Finally, emulating PV modules is necessary for testing electrical components of a PV system. PV emulation simplifies and standardizes the tests allowing for different irradiance, temperature and partial shading levels to be easily tested. Proper emulation of PV modules requires an accurate and mathematically simple PV model that incorporates all known system variables so that any PV module can be emulated as the design requires. A non-synchronous buck converter is proposed for the emulation of a single, high-power PV module using traditional silicon devices. With the proof-of-concept working and improvements in efficiency, power density and steady-state errors made, dynamic tests were performed using an inverter connected to the PV emulator. In order to improve the dynamic characteristics, a synchronous buck converter topology is proposed along with the use of advanced GaNFET devices which resulted in very high power efficiency and improved dynamic response characteristics when emulating PV modules.

Detecting boosted dark matter from the Sun with large volume neutrino detectors

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

Berger, Joshua; Cui, Yanou; Zhao, Yue, E-mail: jberger@slac.stanford.edu, E-mail: ycui@perimeterinstitute.ca, E-mail: zhaoyue@stanford.edu

2015-02-01

We study novel scenarios where thermal dark matter (DM) can be efficiently captured in the Sun and annihilate into boosted dark matter. In models with semi-annihilating DM, where DM has a non-minimal stabilization symmetry, or in models with a multi-component DM sector, annihilations of DM can give rise to stable dark sector particles with moderate Lorentz boosts. We investigate both of these possibilities, presenting concrete models as proofs of concept. Both scenarios can yield viable thermal relic DM with masses O(1)-O(100) GeV. Taking advantage of the energetic proton recoils that arise when the boosted DM scatters off matter, we proposemore » a detection strategy which uses large volume terrestrial detectors, such as those designed to detect neutrinos or proton decays. In particular, we propose a search for proton tracks pointing towards the Sun. We focus on signals at Cherenkov-radiation-based detectors such as Super-Kamiokande (SK) and its upgrade Hyper-Kamiokande (HK). We find that with spin-dependent scattering as the dominant DM-nucleus interaction at low energies, boosted DM can leave detectable signals at SK or HK, with sensitivity comparable to DM direct detection experiments while being consistent with current constraints. Our study provides a new search path for DM sectors with non-minimal structure.« less

Prime-boost immunization using a DNA vaccine delivered by attenuated Salmonella enterica serovar typhimurium and a killed vaccine completely protects chickens from H5N1 highly pathogenic avian influenza virus.

PubMed

Pan, Zhiming; Zhang, Xiaoming; Geng, Shizhong; Fang, Qiang; You, Meng; Zhang, Lei; Jiao, Xinan; Liu, Xiufan

2010-04-01

H5N1 highly pathogenic avian influenza virus (HPAIV) has posed a great threat not only for the poultry industry but also for human health. However, an effective vaccine to provide a full spectrum of protection is lacking in the poultry field. In the current study, a novel prime-boost vaccination strategy against H5N1 HPAIV was developed: chickens were first orally immunized with a hemagglutinin (HA) DNA vaccine delivered by attenuated Salmonella enterica serovar Typhimurium, and boosting with a killed vaccine followed. Chickens in the combined vaccination group but not in single vaccination and control groups were completely protected against disease following H5N1 HPAIV intranasal challenge, with no clinical signs and virus shedding. Chickens in the prime-boost group also generated significantly higher serum hemagglutination inhibition (HI) titers and intestinal mucosal IgA titers against avian influenza virus (AIV) and higher host immune cellular responses than those from other groups before challenge. These results demonstrated that the prime-boost vaccination strategy provides an effective way to prevent and control H5N1 highly pathogenic avian influenza virus.

Detecting boosted dark matter from the Sun with large volume neutrino detectors

NASA Astrophysics Data System (ADS)

Berger, Joshua; Cui, Yanou; Zhao, Yue

2015-02-01

We study novel scenarios where thermal dark matter (DM) can be efficiently captured in the Sun and annihilate into boosted dark matter. In models with semi-annihilating DM, where DM has a non-minimal stabilization symmetry, or in models with a multi-component DM sector, annihilations of DM can give rise to stable dark sector particles with moderate Lorentz boosts. We investigate both of these possibilities, presenting concrete models as proofs of concept. Both scenarios can yield viable thermal relic DM with masses O(1)-O(100) GeV. Taking advantage of the energetic proton recoils that arise when the boosted DM scatters off matter, we propose a detection strategy which uses large volume terrestrial detectors, such as those designed to detect neutrinos or proton decays. In particular, we propose a search for proton tracks pointing towards the Sun. We focus on signals at Cherenkov-radiation-based detectors such as Super-Kamiokande (SK) and its upgrade Hyper-Kamiokande (HK). We find that with spin-dependent scattering as the dominant DM-nucleus interaction at low energies, boosted DM can leave detectable signals at SK or HK, with sensitivity comparable to DM direct detection experiments while being consistent with current constraints. Our study provides a new search path for DM sectors with non-minimal structure.

General equilibrium second-order hydrodynamic coefficients for free quantum fields

NASA Astrophysics Data System (ADS)

Buzzegoli, M.; Grossi, E.; Becattini, F.

2017-10-01

We present a systematic calculation of the corrections of the stress-energy tensor and currents of the free boson and Dirac fields up to second order in thermal vorticity, which is relevant for relativistic hydrodynamics. These corrections are non-dissipative because they survive at general thermodynamic equilibrium with non vanishing mean values of the conserved generators of the Lorentz group, i.e. angular momenta and boosts. Their equilibrium nature makes it possible to express the relevant coefficients by means of correlators of the angular-momentum and boost operators with stress-energy tensor and current, thus making simpler to determine their so-called "Kubo formulae". We show that, at least for free fields, the corrections are of quantum origin and we study several limiting cases and compare our results with previous calculations. We find that the axial current of the free Dirac field receives corrections proportional to the vorticity independently of the anomalous term.

Adaptive fractional order sliding mode control for Boost converter in the Battery/Supercapacitor HESS

PubMed Central

Xu, Dan; Zhou, Huan; Zhou, Tao

2018-01-01

In this paper, an adaptive fractional order sliding mode control (AFSMC) scheme is designed for the current tracking control of the Boost-type converter in a Battery/Supercapacitor hybrid energy storage system (HESS). In order to stabilize the current, the adaptation rules based on state-observer and Lyapunov function are being designed. A fractional order sliding surface function is defined based on the tracking current error and adaptive rules. Furthermore, through fractional order analysis, the stability of the fractional order control system is proven, and the value of the fractional order (λ) is being investigated. In addition, the effectiveness of the proposed AFSMC strategy is being verified by numerical simulations. The advantages of good transient response and robustness to uncertainty are being indicated by this design, when compared with a conventional integer order sliding mode control system. PMID:29702696

Screening of primary gp120 immunogens to formulate the next generation polyvalent DNA prime-protein boost HIV-1 vaccines

PubMed Central

Wang, Shixia; Chou, Te-hui; Hackett, Anthony; Efros, Veronica; Wang, Yan; Han, Dong; Wallace, Aaron; Chen, Yuxin; Hu, Guangnan; Liu, Shuying; Clapham, Paul; Arthos, James; Montefiori, David; Lu, Shan

2017-01-01

ABSTRACT Our previous preclinical studies and a Phase I clinical trial DP6-001 have indicated that a polyvalent Env formulation was able to elicit broadly reactive antibody responses including low titer neutralizing antibody responses against viral isolates of subtypes A, B, C and AE. In the current report, a panel of 62 gp120 immunogens were screened in a rabbit model to identify gp120 immunogens that can elicit improved binding and neutralizing antibody responses and some of them can be included in the next polyvalent formulation. Only about 19% of gp120 immunogens in this panel were able to elicit neutralizing antibodies against greater than 50% of the viruses included in a high throughput PhenoSense neutralization assay when these immuongens were tested as a DNA prime followed by a fixed 5-valent gp120 protein vaccine boost. The new polyvalent formulation, using five gp120 immunogens selected from this subgroup, elicited improved quality of antibody responses in rabbits than the previous DP6-001 formulation. More significantly, this new polyvalent formulation elicited higher antibody responses against a panel of gp70V1/V2 antigens expressing V1/V2 sequences from diverse subtypes. Bioinformatics analysis supports the design of a 4-valent or 5-valent formulation using gp120 immunogens from this screening study to achieve a broad coverage against 16 HIV-1 subtypes. PMID:28933684

Effect of Fermented Cocoa Pod Husk Level in Concentrate on Etawah Grade Semen Quality

NASA Astrophysics Data System (ADS)

Munier, F. F.

2018-02-01

The purpose of study was to determine the effect of fermented CPH supplementation level in concentrate toward semen quality of Etawah Grade Buck (EGB). This research was conducted from August to October, 2011 at experiment pen and Feeds Science Laboratory, Faculty of Animal Science, Universitas Gadjah, Yogyakarta. Semen was collected from 4 heads of EGB with about 2 years old and weight approximately of 24 kg. Concentrate was main material of CPH fermentation with composition P0 0, P1 20%, P2 40% and P3 60% from total of ration. The composer was used by the Aspergillus niger BPT with density 9.1 × 107 of colony/g as many as 1% of CPH material (on dry matter). Semen collection was done every 1 time/week and to be done five times semen collection. An examination was consisting of volume, color, smell, consistency, and the pH. Meanwhile, for microscopic examination was motion of mass, individual, motility, viability of spermatozoa. pH of P0, P1, P2 and P3 were 6.95, 7.03, 7.50 and 7.79, respectively. Mass movement of P0, P1, P2 and P3 were +++, +++, ++ and ++, while viability of P0, P1, P2 and P3 were 79.57%, 79.47%, 59.97% and 51.13%, respectively. It was concluded that addition of CPH fermentation in concentrates up to 20% for of EGB has not affect to feed consumption but it has affect to decreasing of semen quality in both of microscopic and microscopic.

Modeling Learning and Memory Using Verbal Learning Tests: Results From ACTIVE

PubMed Central

Gross, Alden L.

2013-01-01

Objective. To investigate the influence of memory training on initial recall and learning. Method. The Advanced Cognitive Training for Independent and Vital Elderly study of community-dwelling adults older than age 65 (n = 1,401). We decomposed trial-level recall in the Auditory Verbal Learning Test (AVLT) and Hopkins Verbal Learning Test (HVLT) into initial recall and learning across trials using latent growth models. Results. Trial-level increases in words recalled in the AVLT and HVLT at each follow-up visit followed an approximately logarithmic shape. Over the 5-year study period, memory training was associated with slower decline in Trial 1 AVLT recall (Cohen’s d = 0.35, p = .03) and steep pre- and posttraining acceleration in learning (d = 1.56, p < .001). Findings were replicated using the HVLT (decline in initial recall, d = 0.60, p = .01; pre- and posttraining acceleration in learning, d = 3.10, p < .001). Because of the immediate training boost, the memory-trained group had a higher level of recall than the control group through the end of the 5-year study period despite faster decline in learning. Discussion. This study contributes to the understanding of the mechanisms by which training benefits memory and expands current knowledge by reporting long-term changes in initial recall and learning, as measured from growth models and by characterization of the impact of memory training on these components. Results reveal that memory training delays the worsening of memory span and boosts learning. PMID:22929389

Modeling learning and memory using verbal learning tests: results from ACTIVE.

PubMed

Gross, Alden L; Rebok, George W; Brandt, Jason; Tommet, Doug; Marsiske, Michael; Jones, Richard N

2013-03-01

To investigate the influence of memory training on initial recall and learning. The Advanced Cognitive Training for Independent and Vital Elderly study of community-dwelling adults older than age 65 (n = 1,401). We decomposed trial-level recall in the Auditory Verbal Learning Test (AVLT) and Hopkins Verbal Learning Test (HVLT) into initial recall and learning across trials using latent growth models. Trial-level increases in words recalled in the AVLT and HVLT at each follow-up visit followed an approximately logarithmic shape. Over the 5-year study period, memory training was associated with slower decline in Trial 1 AVLT recall (Cohen's d = 0.35, p = .03) and steep pre- and posttraining acceleration in learning (d = 1.56, p < .001). Findings were replicated using the HVLT (decline in initial recall, d = 0.60, p = .01; pre- and posttraining acceleration in learning, d = 3.10, p < .001). Because of the immediate training boost, the memory-trained group had a higher level of recall than the control group through the end of the 5-year study period despite faster decline in learning. This study contributes to the understanding of the mechanisms by which training benefits memory and expands current knowledge by reporting long-term changes in initial recall and learning, as measured from growth models and by characterization of the impact of memory training on these components. Results reveal that memory training delays the worsening of memory span and boosts learning.

MicroRNA profile of silk gland reveals different silk yields of three silkworm strains.

PubMed

Qin, Sheng; Danso, Blessing; Zhang, Jing; Li, Juan; Liu, Na; Sun, Xia; Hou, Chengxiang; Luo, Heng; Chen, Keping; Zhang, Guozheng; Li, Muwang

2018-05-05

Silk proteins are synthesized and secreted by the silk gland. The differential gene expression in it leads to different silk yield among various silkworm strains. As crucial factors, microRNAs (miRNAs) regulate protein synthesis at post-transcriptional level in silk gland. MiRNAs expression level in the silk gland of three silkworm strains (Jingsong, Lan10 and Dazao) was analyzed and 33 differentially expressed miRNAs (DEMs) were discovered between JingSong (JS) and Lan10 (L10), 60 DEMs between JS and Dazao, 54 DEMs between L10 and Dazao respectively. The DEMs target genes were predicted combing with two different methods and their functions were annotated according to gene ontology. Our previous studies showed that a batch of genes related to silk yield were identified in JS and L10 strains by comparative transcriptome and quantitative trait loci (QTL) method. Thirteen DEMs whose target genes are related to protein biosynthesis processes were screened by combining with these researches. Twelve DEMs potentially regulate nineteen genes which exist in our QTL results. Six common DEMs potentially regulate the genes in both of previous results. Finally, five DEMs were selected to verify their expression levels between JS and L10 by qRT-PCR, which showed similar difference as the results of small RNA-sequencing. MiRNAs in the silk gland may directly affect silk protein biosynthesis in different silkworm strains. In current work, we identified a batch of DEMs which potentially regulate the genes related to silk yield. Further functionally study of these miRNAs will contribute to improve varieties and boost the silk yield. Our research provides a basis for studying these miRNAs and their functions in silk production. Copyright © 2018 Elsevier B.V. All rights reserved.

An Elite Vision.

ERIC Educational Resources Information Center

Evelyn, Jamilah

2002-01-01

Explores how Ronald Williams, the president of Prince George's Community College, is bucking tradition in hopes of raising his institution's profile. Discusses how his focus on excellence over access has caused some controversy. (EV)

Searching for flavor changing neutral currents in t →H c , H →τ τ decays at the LHC

NASA Astrophysics Data System (ADS)

Chen, Xin; Xia, Li-Gang

2016-06-01

The prospects of searching for the flavor changing neutral current effect in the decay of t →H c , H →τ τ are investigated with the simulated p -p collision data for the ATLAS detector at the LHC, where the Higgs mass is assumed to be 125 GeV. A fit based on the constraints from the Higgs mass and the tau decay kinematics is performed for each event, which improves significantly the Higgs and top mass reconstruction and helps the signal-background separation. Boosted decision trees discriminants are developed to achieve an optimal sensitivity of searching for the flavor changing neutral current signal. An expected upper limit of the branching ratio B (t →H c ) at 95% confidence level of 0.25% is obtained with a data set of 100 fb-1 at √{s }=13 TeV during the LHC Run-2 period.

Risk-adaptive radiotherapy

NASA Astrophysics Data System (ADS)

Kim, Yusung

Currently, there is great interest in integrating biological information into intensity-modulated radiotherapy (IMRT) treatment planning with the aim of boosting high-risk tumor subvolumes. Selective boosting of tumor subvolumes can be accomplished without violating normal tissue complication constraints using information from functional imaging. In this work we have developed a risk-adaptive optimization-framework that utilizes a nonlinear biological objective function. Employing risk-adaptive radiotherapy for prostate cancer, it is possible to increase the equivalent uniform dose (EUD) by up to 35.4 Gy in tumor subvolumes having the highest risk classification without increasing normal tissue complications. Subsequently, we have studied the impact of functional imaging accuracy, and found on the one hand that loss in sensitivity had a large impact on expected local tumor control, which was maximal when a low-risk classification for the remaining low risk PTV was chosen. While on the other hand loss in specificity appeared to have a minimal impact on normal tissue sparing. Therefore, it appears that in order to improve the therapeutic ratio a functional imaging technique with a high sensitivity, rather than specificity, is needed. Last but not least a comparison study between selective boosting IMRT strategies and uniform-boosting IMRT strategies yielding the same EUD to the overall PTV was carried out, and found that selective boosting IMRT considerably improves expected TCP compared to uniform-boosting IMRT, especially when lack of control of the high-risk tumor subvolumes is the cause of expected therapy failure. Furthermore, while selective boosting IMRT, using physical dose-volume objectives, did yield similar rectal and bladder sparing when compared its equivalent uniform-boosting IMRT plan, risk-adaptive radiotherapy, utilizing biological objective functions, did yield a 5.3% reduction in NTCP for the rectum. Hence, in risk-adaptive radiotherapy the therapeutic ratio can be increased over that which can be achieved with conventional selective boosting IMRT using physical dose-volume objectives. In conclusion, a novel risk-adaptive radiotherapy strategy is proposed and promises increased expected local control for locoregionally advanced tumors with equivalent or better normal tissue sparing.

A heterologous prime-boost Ebola virus vaccine regimen induces durable neutralizing antibody response and prevents Ebola virus-like particle entry in mice.

PubMed

Chen, Tan; Li, Dapeng; Song, Yufeng; Yang, Xi; Liu, Qingwei; Jin, Xia; Zhou, Dongming; Huang, Zhong

2017-09-01

Ebola virus (EBOV) is one of the most virulent pathogens known to humans. Neutralizing antibodies play a major role in the protection against EBOV infections. Thus, an EBOV vaccine capable of inducing a long-lasting neutralizing antibody response is highly desirable. We report here that a heterologous prime-boost vaccine regimen can elicit durable EBOV-neutralizing antibody response in mice. A chimpanzee serotype 7 adenovirus expressing EBOV GP (denoted AdC7-GP) was generated and used for priming. A truncated version of EBOV GP1 protein (denoted GP1t) was produced at high levels in Drosophila S2 cells and used for boosting. Mouse immunization studies showed that the AdC7-GP prime/GP1t boost vaccine regimen was more potent in eliciting neutralizing antibodies than either the AdC7-GP or GP1t alone. Neutralizing antibodies induced by the heterologous prime-boost regimen sustained at high titers for at least 18 weeks after immunization. Significantly, in vivo challenge studies revealed that the entry of reporter EBOV-like particles was efficiently blocked in mice receiving the heterologous prime-boost regimen even at 18 weeks after the final dose of immunization. These results suggest that this novel AdC7-GP prime/GP1t boost regimen represents an EBOV vaccine approach capable of establishing long-term protection, and therefore warrants further development. Copyright © 2017 Elsevier B.V. All rights reserved.

Retroperitoneal sarcoma (RPS) high risk gross tumor volume boost (HR GTV boost) contour delineation agreement among NRG sarcoma radiation and surgical oncologists.

PubMed

Baldini, Elizabeth H; Bosch, Walter; Kane, John M; Abrams, Ross A; Salerno, Kilian E; Deville, Curtiland; Raut, Chandrajit P; Petersen, Ivy A; Chen, Yen-Lin; Mullen, John T; Millikan, Keith W; Karakousis, Giorgos; Kendrick, Michael L; DeLaney, Thomas F; Wang, Dian

2015-09-01

Curative intent management of retroperitoneal sarcoma (RPS) requires gross total resection. Preoperative radiotherapy (RT) often is used as an adjuvant to surgery, but recurrence rates remain high. To enhance RT efficacy with acceptable tolerance, there is interest in delivering "boost doses" of RT to high-risk areas of gross tumor volume (HR GTV) judged to be at risk for positive resection margins. We sought to evaluate variability in HR GTV boost target volume delineation among collaborating sarcoma radiation and surgical oncologist teams. Radiation planning CT scans for three cases of RPS were distributed to seven paired radiation and surgical oncologist teams at six institutions. Teams contoured HR GTV boost volumes for each case. Analysis of contour agreement was performed using the simultaneous truth and performance level estimation (STAPLE) algorithm and kappa statistics. HRGTV boost volume contour agreement between the seven teams was "substantial" or "moderate" for all cases. Agreement was best on the torso wall posteriorly (abutting posterior chest abdominal wall) and medially (abutting ipsilateral para-vertebral space and great vessels). Contours varied more significantly abutting visceral organs due to differing surgical opinions regarding planned partial organ resection. Agreement of RPS HRGTV boost volumes between sarcoma radiation and surgical oncologist teams was substantial to moderate. Differences were most striking in regions abutting visceral organs, highlighting the importance of collaboration between the radiation and surgical oncologist for "individualized" target delineation on the basis of areas deemed at risk and planned resection.

Uncovering potential “herbal probiotics” in Juzen-taiho-to through the study of associated bacterial populations

PubMed Central

Montenegro, Diego; Kalpana, Kriti; Chrissian, Christine; Sharma, Ashutosh; Takaoka, Anna; Iacovidou, Maria; Soll, Clifford E.; Aminova, Olga; Heguy, Adriana; Cohen, Lisa; Shen, Steven

2014-01-01

Juzen-taiho-to (JTT) is an immune-boosting formulation of ten medicinal herbs. It is used clinically in East Asia to boost the human immune functions. The active factors in JTT have not been clarified. But, existing evidence suggests that lipopolysaccharide (LPS)-like factors contribute to the activity. To examine this possibility, JTT was subjected to a series of analyses, including high resolution mass spectrometry, which suggested the presence of structural variants of LPS. This finding opened a possibility that JTT contains immune-boosting bacteria. As the first step to characterize the bacteria in JTT, 16S ribosomal RNA sequencing was carried out for Angelica sinensis (dried root), one of the most potent immunostimulatory herbs in JTT. The sequencing revealed a total of 519 bacteria genera in A. sinensis. The most abundant genus was Rahnella, which is widely distributed in water and plants. The abundance of Rahnella appeared to correlate with the immunostimulatory activity of A. sinensis. In conclusion, the current study provided new pieces of evidence supporting the emerging theory of bacterial contribution in immune-boosting herbs. PMID:25547935

More Bang for the Buck: Integrating Green Infrastructure into Existing Public Works Projects

EPA Pesticide Factsheets

shares lessons learned from municipal and county officials experienced in coordinating green infrastructure applications with scheduled street maintenance, park improvements, and projects on public sites.

Antibody Persistence and Immunologic Memory after Sequential Pneumococcal Conjugate and Polysaccharide Vaccination in HIV-Infected Children on Highly Active Antiretroviral Therapy

PubMed Central

Abzug, Mark J.; Song, Lin Ye; Levin, Myron J.; Nachman, Sharon A.; Borkowsky, William; Pelton, Stephen I.

2013-01-01

Background The capacity of pneumococcal vaccination to confer memory in HIV-infected children is critical for durable protection. Methods HIV-infected children 2–<19 years administered two doses of pneumococcal conjugate vaccine (PCV7) and one dose of polysaccharide vaccine (PPV) on HAART were randomized four-five years later to receive a PCV7 or PPV booster. Total and high avidity antibodies to serotypes 1 (PPV) and 6B and 14 (PCV7 and PPV) were determined by ELISA. Memory was defined as persistence of ≥0.5 mcg/mL of serotype-specific antibody on day 0 or change from <0.5 mcg/mL to ≥0.5 mcg/mL between day 0 and week 1, or, ≥4-fold antibody rise between day 0 and week 1. Results Prior to boosting, four to five years after the previous PCV7-PCV7-PPV series, geometric mean concentrations (GMCs) were 0.46 mcg/mL (serotype 1), 1.31 mcg/mL (serotype 6B), and 1.47 mcg/mL (serotype 14), with concentrations ≥0.5 mcg/mL in 41% (serotype 1) to 82% (serotypes 6B and 14). Memory based on antibody concentration ≥0.5 mcg/mL before or 1 week after boosting with PCV7 or PPV was demonstrated in 42–61% for serotype 1 and 87–94% for serotypes 6B and 14, with lower rates based on day 0 to week 1 ≥4-fold antibody rise (serotype 1, 3–13%; serotype 6B, 13–31%; serotype 14, 29–53%). Antibody concentrations post-boosting were greater following PCV7 than PPV for serotypes 6B and 14. Ratios of highly avid to total antibody pre- and post-boosting were 0.5–0.8. Predictors of memory included higher CD4% (nadir before HAART and at P1024 and P1061s entry), CD19% (at P1024 and P1061s entry), and antibody response after the PCV7-PCV7-PPV primary series and lower viral load (at P1024 and P1061s entry) and age. Conclusions Protective antibody concentrations, high avidity, and booster responses to PCV7 or PPV indicative of memory were present four-five years after PCV7-PCV7-PPV in HIV-infected children on HAART. PMID:23954381

Recombinant low-seroprevalent adenoviral vectors Ad26 and Ad35 expressing the respiratory syncytial virus (RSV) fusion protein induce protective immunity against RSV infection in cotton rats.

PubMed

Widjojoatmodjo, Myra N; Bogaert, Lies; Meek, Bob; Zahn, Roland; Vellinga, Jort; Custers, Jerome; Serroyen, Jan; Radošević, Katarina; Schuitemaker, Hanneke

2015-10-05

RSV is an important cause of lower respiratory tract infections in children, the elderly and in those with underlying medical conditions. Although the high disease burden indicates an urgent need for a vaccine against RSV, no licensed RSV vaccine is currently available. We developed an RSV vaccine candidate based on the low-seroprevalent human adenovirus serotypes 26 and 35 (Ad26 and Ad35) encoding the RSV fusion (F) gene. Single immunization of mice with either one of these vectors induced high titers of RSV neutralizing antibodies and high levels of F specific interferon-gamma-producing T cells. A Th1-type immune response was indicated by a high IgG2a/IgG1 ratio of RSV-specific antibodies, strong induction of RSV-specific interferon-gamma and tumor necrosis factor-alpha cytokine producing CD8 Tcells, and low RSV-specific CD4 T-cell induction. Both humoral and cellular responses were increased upon a boost with RSV-F expressing heterologous adenovirus vector (Ad35 boost after Ad26 prime or vice versa). Both single immunization and prime-boost immunization of cotton rats induced high and long-lasting RSV neutralizing antibody titers and protective immunity against lung and nasal RSV A2 virus load up to at least 30 weeks after immunization. Cotton rats were also completely protected against challenge with a RSV B strain (B15/97) after heterologous prime-boost immunization. Lungs from vaccinated animals showed minimal damage or inflammatory infiltrates post-challenge, in contrast to animals vaccinated with formalin-inactivated virus. Our results suggest that recombinant human adenoviral Ad26 and Ad35 vectors encoding the RSV F gene have the potential to provide broad and durable protection against RSV in humans, and appear safe to be investigated in infants. Copyright © 2015 The Authors. Published by Elsevier Ltd.. All rights reserved.

Robust boosting via convex optimization

NASA Astrophysics Data System (ADS)

Rätsch, Gunnar

2001-12-01

In this work we consider statistical learning problems. A learning machine aims to extract information from a set of training examples such that it is able to predict the associated label on unseen examples. We consider the case where the resulting classification or regression rule is a combination of simple rules - also called base hypotheses. The so-called boosting algorithms iteratively find a weighted linear combination of base hypotheses that predict well on unseen data. We address the following issues: o The statistical learning theory framework for analyzing boosting methods. We study learning theoretic guarantees on the prediction performance on unseen examples. Recently, large margin classification techniques emerged as a practical result of the theory of generalization, in particular Boosting and Support Vector Machines. A large margin implies a good generalization performance. Hence, we analyze how large the margins in boosting are and find an improved algorithm that is able to generate the maximum margin solution. o How can boosting methods be related to mathematical optimization techniques? To analyze the properties of the resulting classification or regression rule, it is of high importance to understand whether and under which conditions boosting converges. We show that boosting can be used to solve large scale constrained optimization problems, whose solutions are well characterizable. To show this, we relate boosting methods to methods known from mathematical optimization, and derive convergence guarantees for a quite general family of boosting algorithms. o How to make Boosting noise robust? One of the problems of current boosting techniques is that they are sensitive to noise in the training sample. In order to make boosting robust, we transfer the soft margin idea from support vector learning to boosting. We develop theoretically motivated regularized algorithms that exhibit a high noise robustness. o How to adapt boosting to regression problems? Boosting methods are originally designed for classification problems. To extend the boosting idea to regression problems, we use the previous convergence results and relations to semi-infinite programming to design boosting-like algorithms for regression problems. We show that these leveraging algorithms have desirable theoretical and practical properties. o Can boosting techniques be useful in practice? The presented theoretical results are guided by simulation results either to illustrate properties of the proposed algorithms or to show that they work well in practice. We report on successful applications in a non-intrusive power monitoring system, chaotic time series analysis and a drug discovery process. --- Anmerkung: Der Autor ist Träger des von der Mathematisch-Naturwissenschaftlichen Fakultät der Universität Potsdam vergebenen Michelson-Preises für die beste Promotion des Jahres 2001/2002. In dieser Arbeit werden statistische Lernprobleme betrachtet. Lernmaschinen extrahieren Informationen aus einer gegebenen Menge von Trainingsmustern, so daß sie in der Lage sind, Eigenschaften von bisher ungesehenen Mustern - z.B. eine Klassenzugehörigkeit - vorherzusagen. Wir betrachten den Fall, bei dem die resultierende Klassifikations- oder Regressionsregel aus einfachen Regeln - den Basishypothesen - zusammengesetzt ist. Die sogenannten Boosting Algorithmen erzeugen iterativ eine gewichtete Summe von Basishypothesen, die gut auf ungesehenen Mustern vorhersagen. Die Arbeit behandelt folgende Sachverhalte: o Die zur Analyse von Boosting-Methoden geeignete Statistische Lerntheorie. Wir studieren lerntheoretische Garantien zur Abschätzung der Vorhersagequalität auf ungesehenen Mustern. Kürzlich haben sich sogenannte Klassifikationstechniken mit großem Margin als ein praktisches Ergebnis dieser Theorie herausgestellt - insbesondere Boosting und Support-Vektor-Maschinen. Ein großer Margin impliziert eine hohe Vorhersagequalität der Entscheidungsregel. Deshalb wird analysiert, wie groß der Margin bei Boosting ist und ein verbesserter Algorithmus vorgeschlagen, der effizient Regeln mit maximalem Margin erzeugt. o Was ist der Zusammenhang von Boosting und Techniken der konvexen Optimierung? Um die Eigenschaften der entstehenden Klassifikations- oder Regressionsregeln zu analysieren, ist es sehr wichtig zu verstehen, ob und unter welchen Bedingungen iterative Algorithmen wie Boosting konvergieren. Wir zeigen, daß solche Algorithmen benutzt werden koennen, um sehr große Optimierungsprobleme mit Nebenbedingungen zu lösen, deren Lösung sich gut charakterisieren laesst. Dazu werden Verbindungen zum Wissenschaftsgebiet der konvexen Optimierung aufgezeigt und ausgenutzt, um Konvergenzgarantien für eine große Familie von Boosting-ähnlichen Algorithmen zu geben. o Kann man Boosting robust gegenüber Meßfehlern und Ausreissern in den Daten machen? Ein Problem bisheriger Boosting-Methoden ist die relativ hohe Sensitivität gegenüber Messungenauigkeiten und Meßfehlern in der Trainingsdatenmenge. Um dieses Problem zu beheben, wird die sogenannte 'Soft-Margin' Idee, die beim Support-Vector Lernen schon benutzt wird, auf Boosting übertragen. Das führt zu theoretisch gut motivierten, regularisierten Algorithmen, die ein hohes Maß an Robustheit aufweisen. o Wie kann man die Anwendbarkeit von Boosting auf Regressionsprobleme erweitern? Boosting-Methoden wurden ursprünglich für Klassifikationsprobleme entwickelt. Um die Anwendbarkeit auf Regressionsprobleme zu erweitern, werden die vorherigen Konvergenzresultate benutzt und neue Boosting-ähnliche Algorithmen zur Regression entwickelt. Wir zeigen, daß diese Algorithmen gute theoretische und praktische Eigenschaften haben. o Ist Boosting praktisch anwendbar? Die dargestellten theoretischen Ergebnisse werden begleitet von Simulationsergebnissen, entweder, um bestimmte Eigenschaften von Algorithmen zu illustrieren, oder um zu zeigen, daß sie in der Praxis tatsächlich gut funktionieren und direkt einsetzbar sind. Die praktische Relevanz der entwickelten Methoden wird in der Analyse chaotischer Zeitreihen und durch industrielle Anwendungen wie ein Stromverbrauch-Überwachungssystem und bei der Entwicklung neuer Medikamente illustriert.

Airtightness the simple(CS) way

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

Andrews, S.

Builders who might buck against such time consuming air sealing methods as polyethylene wrap and the airtight drywall approach (ADA) may respond better to current strategies. One such method, called SimpleCS, has proven especially effective. SimpleCS, pronounced simplex, stands for simple caulk and seal. A modification of the ADA, SimpleCS is an air-sealing management tool, a simplified systems approach to building tight homes. The system address the crucial question of when and by whom various air sealing steps should be done. It avoids the problems that often occur when later contractors cut open polyethylene wrap to drill holes in themore » drywall. The author describes how SimpleCS works, and the cost and training involved.« less

Observer-Pattern Modeling and Slow-Scale Bifurcation Analysis of Two-Stage Boost Inverters

NASA Astrophysics Data System (ADS)

Zhang, Hao; Wan, Xiaojin; Li, Weijie; Ding, Honghui; Yi, Chuanzhi

2017-06-01

This paper deals with modeling and bifurcation analysis of two-stage Boost inverters. Since the effect of the nonlinear interactions between source-stage converter and load-stage inverter causes the “hidden” second-harmonic current at the input of the downstream H-bridge inverter, an observer-pattern modeling method is proposed by removing time variance originating from both fundamental frequency and hidden second harmonics in the derived averaged equations. Based on the proposed observer-pattern model, the underlying mechanism of slow-scale instability behavior is uncovered with the help of eigenvalue analysis method. Then eigenvalue sensitivity analysis is used to select some key system parameters of two-stage Boost inverter, and some behavior boundaries are given to provide some design-oriented information for optimizing the circuit. Finally, these theoretical results are verified by numerical simulations and circuit experiment.

Astronaut John Glenn Enters Friendship 7

NASA Technical Reports Server (NTRS)

1962-01-01

Astronaut John Glenn enters the Mercury spacecraft, Friendship 7, prior to the launch of MA-6 on February 20, 1961 and became the first American who orbited the Earth. The MA-6 mission was the first manned orbital flight boosted by the Mercury-Atlas vehicle, a modified Atlas ICBM (Intercontinental Ballistic Missile), lasted for five hours, and orbited the Earth three times.

Public ownership helps boost HMOs' profits.

PubMed

Kenkel, P J

1992-05-04

Health maintenance organizations have found that the route to faster growth and better profitability may be turning into a for-profit business and issuing stock. For the past five years, such organizations have generally outperformed their older, not-for-profit counterparts that rely on debt to fuel growth. Since 1988, HMOs have completed 48 stock and debt offerings, raising $3.6 billion.

15. INTERIOR, NORTHWESTERN WING, SHOW ROOM, DETAIL OF BALCONY ...

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

15. INTERIOR, NORTHWESTERN WING, SHOW ROOM, DETAIL OF BALCONY - Moravian Pottery & Tile Works, Southwest side of State Route 313 (Swamp Road), Northwest of East Court Street, Doylestown, Bucks County, PA

14. INTERIOR, NORTHWESTERN WING, SHOW ROOM, DETAIL OF FIREPLACE ...

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

14. INTERIOR, NORTHWESTERN WING, SHOW ROOM, DETAIL OF FIREPLACE - Moravian Pottery & Tile Works, Southwest side of State Route 313 (Swamp Road), Northwest of East Court Street, Doylestown, Bucks County, PA

19. INTERIOR, VIEW THROUGH TRIANGULARARCHED DOORWAY TO EXTERIOR Moravian ...

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

19. INTERIOR, VIEW THROUGH TRIANGULAR-ARCHED DOORWAY TO EXTERIOR - Moravian Pottery & Tile Works, Southwest side of State Route 313 (Swamp Road), Northwest of East Court Street, Doylestown, Bucks County, PA

Silicon Carbide Diodes Performance Characterization and Comparison With Silicon Devices

NASA Technical Reports Server (NTRS)

Lebron-Velilla, Ramon C.; Schwarze, Gene E.; Trapp, Scott

2003-01-01

Commercially available silicon carbide (SiC) Schottky diodes from different manufacturers were electrically tested and characterized at room temperature. Performed electrical tests include steady state forward and reverse I-V curves, as well as switching transient tests performed with the diodes operating in a hard switch dc-to-dc buck converter. The same tests were performed in current state of the art silicon (Si) and gallium arsenide (GaAs) Schottky and pn junction devices for evaluation and comparison purposes. The SiC devices tested have a voltage rating of 200, 300, and 600 V. The comparison parameters are forward voltage drop at rated current, reverse current at rated voltage and peak reverse recovery currents in the dc to dc converter. Test results show that steady state characteristics of the tested SiC devices are not superior to the best available Si Schottky and ultra fast pn junction devices. Transient tests reveal that the tested SiC Schottky devices exhibit superior transient behavior. This is more evident at the 300 and 600 V rating where SiC Schottky devices showed drastically lower reverse recovery currents than Si ultra fast pn diodes of similar rating.

Silicon Carbide Diodes Performance Characterization at High Temperatures

NASA Technical Reports Server (NTRS)

Lebron-Velilla, Ramon C.; Schwarze, Gene E.; Gardner, Brent G.; Adams, Jerry

2004-01-01

NASA Glenn Research center's Electrical Systems Development branch is working to demonstrate and test the advantages of Silicon Carbide (SiC) devices in actual power electronics applications. The first step in this pursuit is to obtain commercially available SiC Schottky diodes and to individually test them under both static and dynamic conditions, and then compare them with current state of the art silicon Schottky and ultra fast p-n diodes of similar voltage and current ratings. This presentation covers the results of electrical tests performed at NASA Glenn. Steady state forward and reverse current-volt (I-V) curves were generated for each device to compare performance and to measure their forward voltage drop at rated current, as well as the reverse leakage current at rated voltage. In addition, the devices were individually connected as freewheeling diodes in a Buck (step down) DC to DC converter to test their reverse recovery characteristics and compare their transient performance in a typical converter application. Both static and transient characterization tests were performed at temperatures ranging from 25 C to 300 C, in order to test and demonstrate the advantages of SiC over Silicon at high temperatures.

A boosting skin vaccination with dissolving microneedle patch encapsulating M2e vaccine broadens the protective efficacy of conventional influenza vaccines.

PubMed

Zhu, Wandi; Pewin, Winston; Wang, Chao; Luo, Yuan; Gonzalez, Gilbert X; Mohan, Teena; Prausnitz, Mark R; Wang, Bao-Zhong

2017-09-10

The biodegradable microneedle patch (MNP) is a novel technology for vaccine delivery that could improve the immunogenicity of vaccines. To broaden the protective efficiency of conventional influenza vaccines, a new 4M2e-tFliC fusion protein construct containing M2e sequences from different subtypes was generated. Purified fusion protein was encapsulate into MNPs with a biocompatible polymer for use as a boosting vaccine. The results demonstrated that mice receiving a conventional inactivated vaccine followed by a skin-applied dissolving 4M2e-tFliC MNP boost could better maintain the humoral antibody response than that by the conventional vaccine-prime alone. Compared with an intramuscular injection boost, mice receiving the MNP boost showed significantly enhanced cellular immune responses, hemagglutination-inhibition (HAI) titers, and neutralization titers. Increased frequency of antigen-specific plasma cells and long-lived bone marrow plasma cells was detected in the MNP boosted group as well, indicating that skin vaccination with 4M2e-tFliC facilitated a long-term antibody-mediated immunity. The 4M2e-tFliC MNP-boosted group also possessed enhanced protection against high lethal dose challenges against homologous A/PR/8/34 and A/Aichi/2/68 viruses and protection for a majority of immunized mice against a heterologous A/California/07/2009 H1N1 virus. High levels of M2e specific immune responses were observed in the 4M2e-tFliC MNP-boosted group as well. These results demonstrate that a skin-applied 4M2e-tFliC MNP boosting immunization to seasonal vaccine recipients may be a rapid approach for increasing the protective efficacy of seasonal vaccines in response to a significant drift seen in circulating viruses. The results also provide a new perspective for future exploration of universal influenza vaccines. Copyright © 2017 Elsevier B.V. All rights reserved.

Anodal transcranial direct current stimulation boosts synaptic plasticity and memory in mice via epigenetic regulation of Bdnf expression

PubMed Central

Podda, Maria Vittoria; Cocco, Sara; Mastrodonato, Alessia; Fusco, Salvatore; Leone, Lucia; Barbati, Saviana Antonella; Colussi, Claudia; Ripoli, Cristian; Grassi, Claudio

2016-01-01

The effects of transcranial direct current stimulation (tDCS) on brain functions and the underlying molecular mechanisms are yet largely unknown. Here we report that mice subjected to 20-min anodal tDCS exhibited one-week lasting increases in hippocampal LTP, learning and memory. These effects were associated with enhanced: i) acetylation of brain-derived neurotrophic factor (Bdnf) promoter I; ii) expression of Bdnf exons I and IX; iii) Bdnf protein levels. The hippocampi of stimulated mice also exhibited enhanced CREB phosphorylation, pCREB binding to Bdnf promoter I and recruitment of CBP on the same regulatory sequence. Inhibition of acetylation and blockade of TrkB receptors hindered tDCS effects at molecular, electrophysiological and behavioral levels. Collectively, our findings suggest that anodal tDCS increases hippocampal LTP and memory via chromatin remodeling of Bdnf regulatory sequences leading to increased expression of this gene, and support the therapeutic potential of tDCS for brain diseases associated with impaired neuroplasticity. PMID:26908001

L-type calcium channels refine the neural population code of sound level

PubMed Central

Grimsley, Calum Alex; Green, David Brian

2016-01-01

The coding of sound level by ensembles of neurons improves the accuracy with which listeners identify how loud a sound is. In the auditory system, the rate at which neurons fire in response to changes in sound level is shaped by local networks. Voltage-gated conductances alter local output by regulating neuronal firing, but their role in modulating responses to sound level is unclear. We tested the effects of L-type calcium channels (CaL: CaV1.1–1.4) on sound-level coding in the central nucleus of the inferior colliculus (ICC) in the auditory midbrain. We characterized the contribution of CaL to the total calcium current in brain slices and then examined its effects on rate-level functions (RLFs) in vivo using single-unit recordings in awake mice. CaL is a high-threshold current and comprises ∼50% of the total calcium current in ICC neurons. In vivo, CaL activates at sound levels that evoke high firing rates. In RLFs that increase monotonically with sound level, CaL boosts spike rates at high sound levels and increases the maximum firing rate achieved. In different populations of RLFs that change nonmonotonically with sound level, CaL either suppresses or enhances firing at sound levels that evoke maximum firing. CaL multiplies the gain of monotonic RLFs with dynamic range and divides the gain of nonmonotonic RLFs with the width of the RLF. These results suggest that a single broad class of calcium channels activates enhancing and suppressing local circuits to regulate the sensitivity of neuronal populations to sound level. PMID:27605536

Dietary omega-3 polyunsaturated fatty acids induce plasminogen activator activity and DNA damage in rabbit spermatozoa.

PubMed

Kokoli, A N; Lavrentiadou, S N; Zervos, I A; Tsantarliotou, M P; Georgiadis, M P; Nikolaidis, E A; Botsoglou, N; Boscos, C M; Taitzoglou, I A

2017-12-01

The aim of this study was to determine the effect(s) of dietary omega-3 polyunsaturated fatty acids (ω-3 PUFA) on rabbit semen. Adult rabbit bucks were assigned to two groups that were given two diets, a standard diet (control) and a diet supplemented with ω-3 PUFA. Sperm samples were collected from all bucks with the use of an artificial vagina in 20-day intervals, for a total period of 120 days. The enrichment of membranes in ω-3 PUFA was manifested by the elevation of the 22:5 ω-3 (docosapentaenoic acid [DPA]) levels within 40 days. This increase in DPA content did not affect semen characteristics (i.e., concentration, motility and viability). However, it was associated with the induction of lipid peroxidation in spermatozoa, as determined on the basis of the malondialdehyde content. Lipid peroxidation was associated with DNA fragmentation in ω-3 PUFA-enriched spermatozoa and a concomitant increase in plasminogen activator (PA) activity. The effects of ω-3 PUFA on sperm cells were evident within 40 days of ω-3 PUFA dietary intake and exhibited peack values on day 120. Our findings suggest that an ω-3 PUFA-rich diet may not affect semen characteristics; however, it may have a negative impact on the oxidative status and DNA integrity of the spermatozoa, which was associated with an induction of PAs activity. © 2017 Blackwell Verlag GmbH.

"Before" Main House, photographic copy of ca. 1834 watercolor by ...

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

"Before" Main House, photographic copy of ca. 1834 watercolor by Thomas U. Walter. Duplicate color view of HABS PA-1248-35 - Andalusia, State Road vicinity (Bensalem Township), Andalusia, Bucks County, PA

Structured decision making as a framework for large-scale wildlife harvest management decisions

USGS Publications Warehouse

Robinson, Kelly F.; Fuller, Angela K.; Hurst, Jeremy E.; Swift, Bryan L.; Kirsch, Arthur; Farquhar, James F.; Decker, Daniel J.; Siemer, William F.

2016-01-01

Fish and wildlife harvest management at large spatial scales often involves making complex decisions with multiple objectives and difficult tradeoffs, population demographics that vary spatially, competing stakeholder values, and uncertainties that might affect management decisions. Structured decision making (SDM) provides a formal decision analytic framework for evaluating difficult decisions by breaking decisions into component parts and separating the values of stakeholders from the scientific evaluation of management actions and uncertainty. The result is a rigorous, transparent, and values-driven process. This decision-aiding process provides the decision maker with a more complete understanding of the problem and the effects of potential management actions on stakeholder values, as well as how key uncertainties can affect the decision. We use a case study to illustrate how SDM can be used as a decision-aiding tool for management decision making at large scales. We evaluated alternative white-tailed deer (Odocoileus virginianus) buck-harvest regulations in New York designed to reduce harvest of yearling bucks, taking into consideration the values of the state wildlife agency responsible for managing deer, as well as deer hunters. We incorporated tradeoffs about social, ecological, and economic management concerns throughout the state. Based on the outcomes of predictive models, expert elicitation, and hunter surveys, the SDM process identified management alternatives that optimized competing objectives. The SDM process provided biologists and managers insight about aspects of the buck-harvest decision that helped them adopt a management strategy most compatible with diverse hunter values and management concerns.

Stratigraphic cross section of measured sections and drill holes of the Neslan Formation and adjacent formations, Book Cliffs Area, Colorado and Utah

USGS Publications Warehouse

Kirshbaum, Mark A.; Spear, Brianne D.

2012-01-01

This study updates a stratigraphic cross section published as plate 2 in Kirschbaum and Hettinger (2004) Digital Data Series 69-G (http://pubs.usgs.gov/dds/dds-069/dds-069-g/). The datum is a marine/tidal ravinement surface within the Cozzette Sandstone Member of the Iles Formation and the Thompson Canyon Sandstone and Sulphur Canyon Sandstone Beds of the Neslen Formation. One of the cores shown was included on the original cross section, and new core descriptions have been added to the upper part of the cored interval. A new core description (S178) is included in this report. Cores are stored in the U.S. Geological Survey Core Research Facility at the Denver Federal Center, Colorado. The following information has also been added to help define the stratigraphic framework: 1) At least five claystones interpreted as altered volcanic ashes have been identified and may give future workers a correlation tool within the largely continental section. 2) Thickness and general geometry of the Sego Sandstone, Buck Tongue of the Mancos Shale, and Castlegate Sandstone have been added to provide additional stratigraphic context. 3) The geometry in the Sego Sandstone, Buck Tongue of the Mancos Shale, and Castlegate Sandstone has been added to provide additional stratigraphic context. 4) Ammonite collections are from Gill and Hail. The zone of Didymoceras nebrascense projected into the East Salt Wash area is based on correlation of the flooding surface at the base of the Cozzette Member to this point as shown in Kirschbaum and Hettinger. 5) A leaf locality of the Denver Museum of Nature and Science is shown in its approximate stratigraphic position near Thompson Canyon. 6) A dinosaur locality of the Natural History Museum of Utah is shown in the Horse Canyon area measured section at the stratigraphic position where it was extracted.

NASA Tech Briefs, February 2005

NASA Technical Reports Server (NTRS)

2005-01-01

Topics discussed include: Instrumentation for Sensitive Gas Measurements; Apparatus for Testing Flat Specimens of Thermal Insulation; Quadrupole Ion Mass Spectrometer for Masses of 2 to 50 Da; Miniature Laser Doppler Velocimeter for Measuring Wall Shear; Coherent Laser Instrument Would Measure Range and Velocity; Printed Microinductors for Flexible Substrates; Digital Receiver for Microwave Radiometry; Printed Antennas Made Reconfigurable by Use of MEMS Switches; Traffic-Light-Preemption Vehicle-Transponder Software Module; Intersection-Controller Software Module; Central-Monitor Software Module; Estimating Effects of Multipath Propagation on GPS Signals; Parallel Adaptive Mesh Refinement Library; Predicting Noise From Aircraft Turbine-Engine Combustors; Generating Animated Displays of Spacecraft Orbits; Diagnosis and Prognosis of Weapon Systems; Training Software in Artificial-Intelligence Computing Techniques; APGEN Version 5.0; Single-Command Approach and Instrument Placement by a Robot on a Target; Three-Dimensional Audio Client Library; Isogrid Membranes for Precise, Singly Curved Reflectors; Nickel-Tin Electrode Materials for Nonaqueous Li-Ion Cells; Photocatalytic Coats in Glass Drinking-Water Bottles; Fast Laser Shutters With Low Vibratory Disturbances; Series-Connected Buck Boost Regulators; Space Physics Data Facility Web Services; Split-Resonator, Integrated-Post Vibratory Microgyroscope; Blended Buffet-Load-Alleviation System for Fighter Airplane; Gifford-McMahon/Joule-Thomson Refrigerator Cools to 2.5 K; High-Temperature, High-Load-Capacity Radial Magnetic Bearing; Fabrication of Spherical Reflectors in Outer Space; Automated Rapid Prototyping of 3D Ceramic Parts; Tissue Engineering Using Transfected Growth-Factor Genes; Automation of Vapor-Diffusion Growth of Protein Crystals; Atom Skimmers and Atom Lasers Utilizing Them; Gears Based on Carbon Nanotubes; Patched Off-Axis Bending/Twisting Actuators for Thin Mirrors; and Improving Control in a Joule-Thomson Refrigerator.

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

Larkoski, Andrew J.; Maltoni, Fabio; Selvaggi, Michele

The identification of hadronically decaying heavy states, such as vector bosons, the Higgs, or the top quark, produced with large transverse boosts has been and will continue to be a central focus of the jet physics program at the Large Hadron Collider (LHC). At a future hadron collider working at an order-of-magnitude larger energy than the LHC, these heavy states would be easily produced with transverse boosts of several TeV. At these energies, their decay products will be separated by angular scales comparable to individual calorimeter cells, making the current jet substructure identification techniques for hadronic decay modes not directlymore » employable. In addition, at the high energy and luminosity projected at a future hadron collider, there will be numerous sources for contamination including initial- and final-state radiation, underlying event, or pile-up which must be mitigated. We propose a simple strategy to tag such "hyper-boosted" objects that defines jets with radii that scale inversely proportional to their transverse boost and combines the standard calorimetric information with charged track-based observables. By means of a fast detector simulation, we apply it to top quark identification and demonstrate that our method efficiently discriminates hadronically decaying top quarks from light QCD jets up to transverse boosts of 20 TeV. Lastly, our results open the way to tagging heavy objects with energies in the multi-TeV range at present and future hadron colliders.« less

Menthol smokers: metabolomic profiling and smoking behavior

PubMed Central

Hsu, Ping-Ching; Lan, Renny S.; Brasky, Theodore M.; Marian, Catalin; Cheema, Amrita K.; Ressom, Habtom W.; Loffredo, Christopher A.; Pickworth, Wallace B.; Shields, Peter G.

2016-01-01

Background The use of menthol in cigarettes and marketing is under consideration for regulation by the FDA. However, the effects of menthol on smoking behavior and carcinogen exposure have been inconclusive. We previously reported metabolomic profiling for cigarette smokers, and novelly identified a menthol-glucuronide (MG) as the most significant metabolite directly related to smoking. Here, MG is studied in relation to smoking behavior and metabolomic profiles. Methods A cross-sectional study of 105 smokers who smoked two cigarettes in the laboratory one hour apart. Blood nicotine, MG and exhaled carbon monoxide (CO) boosts were determined (the difference before and after smoking). Spearman's correlation, Chi-Square and ANCOVA adjusted for gender, race and cotinine levels for menthol smokers assessed the relationship of MG boost, smoking behavior, and metabolic profiles. Multivariate metabolite characterization using supervised Partial Least Squares-Discriminant Analysis (PLS-DA) was carried out for the classification of metabolomics profiles. Results MG boost was positively correlated with CO boost, nicotine boost, average puff volume, puff duration, and total smoke exposure. Classification using PLS-DA, MG was the top metabolite discriminating metabolome of menthol vs. non-menthol smokers. Among menthol smokers, forty-two metabolites were significantly correlated with MG boost, which linked to cellular functions such as of cell death, survival, and movement. Conclusion Plasma MG boost is a new smoking behavior biomarker that may provides novel information over self-reported use of menthol cigarettes by integrating different smoking measures for understanding smoking behavior and harm of menthol cigarettes. Impacts These results provide insight into the biological effect of menthol smoking. PMID:27628308

Characterization of photomultiplier tubes with a realistic model through GPU-boosted simulation

NASA Astrophysics Data System (ADS)

Anthony, M.; Aprile, E.; Grandi, L.; Lin, Q.; Saldanha, R.

2018-02-01

The accurate characterization of a photomultiplier tube (PMT) is crucial in a wide-variety of applications. However, current methods do not give fully accurate representations of the response of a PMT, especially at very low light levels. In this work, we present a new and more realistic model of the response of a PMT, called the cascade model, and use it to characterize two different PMTs at various voltages and light levels. The cascade model is shown to outperform the more common Gaussian model in almost all circumstances and to agree well with a newly introduced model independent approach. The technical and computational challenges of this model are also presented along with the employed solution of developing a robust GPU-based analysis framework for this and other non-analytical models.

Reef flattening effects on total richness and species responses in the Caribbean.

PubMed

Newman, Steven P; Meesters, Erik H; Dryden, Charlie S; Williams, Stacey M; Sanchez, Cristina; Mumby, Peter J; Polunin, Nicholas V C

2015-11-01

There has been ongoing flattening of Caribbean coral reefs with the loss of habitat having severe implications for these systems. Complexity and its structural components are important to fish species richness and community composition, but little is known about its role for other taxa or species-specific responses. This study reveals the importance of reef habitat complexity and structural components to different taxa of macrofauna, total species richness, and individual coral and fish species in the Caribbean. Species presence and richness of different taxa were visually quantified in one hundred 25-m(2) plots in three marine reserves in the Caribbean. Sampling was evenly distributed across five levels of visually estimated reef complexity, with five structural components also recorded: the number of corals, number of large corals, slope angle, maximum sponge and maximum octocoral height. Taking advantage of natural heterogeneity in structural complexity within a particular coral reef habitat (Orbicella reefs) and discrete environmental envelope, thus minimizing other sources of variability, the relative importance of reef complexity and structural components was quantified for different taxa and individual fish and coral species on Caribbean coral reefs using boosted regression trees (BRTs). Boosted regression tree models performed very well when explaining variability in total (82·3%), coral (80·6%) and fish species richness (77·3%), for which the greatest declines in richness occurred below intermediate reef complexity levels. Complexity accounted for very little of the variability in octocorals, sponges, arthropods, annelids or anemones. BRTs revealed species-specific variability and importance for reef complexity and structural components. Coral and fish species occupancy generally declined at low complexity levels, with the exception of two coral species (Pseudodiploria strigosa and Porites divaricata) and four fish species (Halichoeres bivittatus, H. maculipinna, Malacoctenus triangulatus and Stegastes partitus) more common at lower reef complexity levels. A significant interaction between country and reef complexity revealed a non-additive decline in species richness in areas of low complexity and the reserve in Puerto Rico. Flattening of Caribbean coral reefs will result in substantial species losses, with few winners. Individual structural components have considerable value to different species, and their loss may have profound impacts on population responses of coral and fish due to identity effects of key species, which underpin population richness and resilience and may affect essential ecosystem processes and services. © 2015 The Authors. Journal of Animal Ecology © 2015 British Ecological Society.

Replica Exchange Gaussian Accelerated Molecular Dynamics: Improved Enhanced Sampling and Free Energy Calculation.

PubMed

Huang, Yu-Ming M; McCammon, J Andrew; Miao, Yinglong

2018-04-10

Through adding a harmonic boost potential to smooth the system potential energy surface, Gaussian accelerated molecular dynamics (GaMD) provides enhanced sampling and free energy calculation of biomolecules without the need of predefined reaction coordinates. This work continues to improve the acceleration power and energy reweighting of the GaMD by combining the GaMD with replica exchange algorithms. Two versions of replica exchange GaMD (rex-GaMD) are presented: force constant rex-GaMD and threshold energy rex-GaMD. During simulations of force constant rex-GaMD, the boost potential can be exchanged between replicas of different harmonic force constants with fixed threshold energy. However, the algorithm of threshold energy rex-GaMD tends to switch the threshold energy between lower and upper bounds for generating different levels of boost potential. Testing simulations on three model systems, including the alanine dipeptide, chignolin, and HIV protease, demonstrate that through continuous exchanges of the boost potential, the rex-GaMD simulations not only enhance the conformational transitions of the systems but also narrow down the distribution width of the applied boost potential for accurate energetic reweighting to recover biomolecular free energy profiles.

Investigation of the charge boost technology for the efficiency increase of closed sorption thermal energy storage systems

NASA Astrophysics Data System (ADS)

Rohringer, C.; Engel, G.; Köll, R.; Wagner, W.; van Helden, W.

2017-10-01

The inclusion of solar thermal energy into energy systems requires storage possibilities to overcome the gap between supply and demand. Storage of thermal energy with closed sorption thermal energy systems has the advantage of low thermal losses and high energy density. However, the efficiency of these systems needs yet to be increased to become competitive on the market. In this paper, the so-called “charge boost technology” is developed and tested via experiments as a new concept for the efficiency increase of compact thermal energy storages. The main benefit of the charge boost technology is that it can reach a defined state of charge for sorption thermal energy storages at lower temperature levels than classic pure desorption processes. Experiments are conducted to provide a proof of principle for this concept. The results show that the charge boost technology does function as predicted and is a viable option for further improvement of sorption thermal energy storages. Subsequently, a new process application is developed by the author with strong focus on the utilization of the advantages of the charge boost technology over conventional desorption processes. After completion of the conceptual design, the theoretical calculations are validated via experiments.

76 FR 5647 - Pennsylvania Disaster #PA-00036

Federal Register 2010, 2011, 2012, 2013, 2014

2011-02-01

... SMALL BUSINESS ADMINISTRATION [Disaster Declaration 12449 and 12450] Pennsylvania Disaster PA... Administrative declaration of a disaster for the Commonwealth of Pennsylvania dated 01/25/2011. Incident... the disaster: Primary Counties: Philadelphia. Contiguous Counties: Pennsylvania: Bucks, Delaware...

2. INTERIOR PERSPECTIVE VIEW OF NORTHEAST AND NORTHWEST WALLS, SHOWING ...

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

2. INTERIOR PERSPECTIVE VIEW OF NORTHEAST AND NORTHWEST WALLS, SHOWING COOK FIREPLACE WITH BAKE OVEN TO REAR - High Farm, Kitchen, Creek Road, 1 mile East of Easton Road, Pipersville, Bucks County, PA

4. DETAIL OF SOUTH (FRONT) ELEVATION AT EAST END OF ...

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

4. DETAIL OF SOUTH (FRONT) ELEVATION AT EAST END OF PORCH WITH STRUCTURAL SYSTEM OF WOOD FRAME WITH BRICK NOGGING REVEALED. - Andalusia, The Cottage, State Road vicinity (Bensalem Township), Andalusia, Bucks County, PA

94. FONTHILL (19081912), SOUTH ELEVATION. SAME VIEW AS PA10764. ...

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

94. FONTHILL (1908-1912), SOUTH ELEVATION. SAME VIEW AS PA-107-64. - Moravian Pottery & Tile Works, Southwest side of State Route 313 (Swamp Road), Northwest of East Court Street, Doylestown, Bucks County, PA

76 FR 2190 - Qualification of Drivers; Exemption Applications; Vision

Federal Register 2010, 2011, 2012, 2013, 2014

2011-01-12

.... The exemptions expire on January 12, 2012. FOR FURTHER INFORMATION CONTACT: Dr. Mary D. Gunnels..., Donald G. Brock, Jr., Anthony D. Buck, Cody W. Cook, Marvin R. Daly, Douglas R. Duncan, Douglas K. Esp...

Multimodality vaccination against clade C SHIV: partial protection against mucosal challenges with a heterologous tier 2 virus.

PubMed

Lakhashe, Samir K; Byrareddy, Siddappa N; Zhou, Mingkui; Bachler, Barbara C; Hemashettar, Girish; Hu, Shiu-Lok; Villinger, Francois; Else, James G; Stock, Shannon; Lee, Sandra J; Vargas-Inchaustegui, Diego A; Cofano, Egidio Brocca; Robert-Guroff, Marjorie; Johnson, Welkin E; Polonis, Victoria R; Forthal, Donald N; Loret, Erwann P; Rasmussen, Robert A; Ruprecht, Ruth M

2014-11-12

We sought to test whether vaccine-induced immune responses could protect rhesus macaques (RMs) against upfront heterologous challenges with an R5 simian-human immunodeficiency virus, SHIV-2873Nip. This SHIV strain exhibits many properties of transmitted HIV-1, such as tier 2 phenotype (relatively difficult to neutralize), exclusive CCR5 tropism, and gradual disease progression in infected RMs. Since no human AIDS vaccine recipient is likely to encounter an HIV-1 strain that exactly matches the immunogens, we immunized the RMs with recombinant Env proteins heterologous to the challenge virus. For induction of immune responses against Gag, Tat, and Nef, we explored a strategy of immunization with overlapping synthetic peptides (OSP). The immune responses against Gag and Tat were finally boosted with recombinant proteins. The vaccinees and a group of ten control animals were given five low-dose intrarectal (i.r.) challenges with SHIV-2873Nip. All controls and seven out of eight vaccinees became systemically infected; there was no significant difference in viremia levels of vaccinees vs. controls. Prevention of viremia was observed in one vaccinee which showed strong boosting of virus-specific cellular immunity during virus exposures. The protected animal showed no challenge virus-specific neutralizing antibodies in the TZM-bl or A3R5 cell-based assays and had low-level ADCC activity after the virus exposures. Microarray data strongly supported a role for cellular immunity in the protected animal. Our study represents a case of protection against heterologous tier 2 SHIV-C by vaccine-induced, virus-specific cellular immune responses. Copyright © 2014 Elsevier Ltd. All rights reserved.

Attentional load and attentional boost: a review of data and theory.

PubMed

Swallow, Khena M; Jiang, Yuhong V

2013-01-01

Both perceptual and cognitive processes are limited in capacity. As a result, attention is selective, prioritizing items and tasks that are important for adaptive behavior. However, a number of recent behavioral and neuroimaging studies suggest that, at least under some circumstances, increasing attention to one task can enhance performance in a second task (e.g., the attentional boost effect). Here we review these findings and suggest a new theoretical framework, the dual-task interaction model, that integrates these findings with current views of attentional selection. To reconcile the attentional boost effect with the effects of attentional load, we suggest that temporal selection results in a temporally specific enhancement across modalities, tasks, and spatial locations. Moreover, the effects of temporal selection may be best observed when the attentional system is optimally tuned to the temporal dynamics of incoming stimuli. Several avenues of research motivated by the dual-task interaction model are then discussed.

A High Voltage Ratio and Low Ripple Interleaved DC-DC Converter for Fuel Cell Applications

PubMed Central

Chang, Long-Yi; Chao, Kuei-Hsiang; Chang, Tsang-Chih

2012-01-01

This paper proposes a high voltage ratio and low ripple interleaved boost DC-DC converter, which can be used to reduce the output voltage ripple. This converter transfers the low DC voltage of fuel cell to high DC voltage in DC link. The structure of the converter is parallel with two voltage-doubler boost converters by interleaving their output voltages to reduce the voltage ripple ratio. Besides, it can lower the current stress for the switches and inductors in the system. First, the PSIM software was used to establish a proton exchange membrane fuel cell and a converter circuit model. The simulated and measured results of the fuel cell output characteristic curve are made to verify the correctness of the established simulation model. In addition, some experimental results are made to validate the effectiveness in improving output voltage ripple of the proposed high voltage ratio interleaved boost DC-DC converters. PMID:23365536

A high voltage ratio and low ripple interleaved DC-DC converter for fuel cell applications.

PubMed

Chang, Long-Yi; Chao, Kuei-Hsiang; Chang, Tsang-Chih

2012-01-01

This paper proposes a high voltage ratio and low ripple interleaved boost DC-DC converter, which can be used to reduce the output voltage ripple. This converter transfers the low DC voltage of fuel cell to high DC voltage in DC link. The structure of the converter is parallel with two voltage-doubler boost converters by interleaving their output voltages to reduce the voltage ripple ratio. Besides, it can lower the current stress for the switches and inductors in the system. First, the PSIM software was used to establish a proton exchange membrane fuel cell and a converter circuit model. The simulated and measured results of the fuel cell output characteristic curve are made to verify the correctness of the established simulation model. In addition, some experimental results are made to validate the effectiveness in improving output voltage ripple of the proposed high voltage ratio interleaved boost DC-DC converters.

Attentional Load and Attentional Boost: A Review of Data and Theory

PubMed Central

Swallow, Khena M.; Jiang, Yuhong V.

2013-01-01

Both perceptual and cognitive processes are limited in capacity. As a result, attention is selective, prioritizing items and tasks that are important for adaptive behavior. However, a number of recent behavioral and neuroimaging studies suggest that, at least under some circumstances, increasing attention to one task can enhance performance in a second task (e.g., the attentional boost effect). Here we review these findings and suggest a new theoretical framework, the dual-task interaction model, that integrates these findings with current views of attentional selection. To reconcile the attentional boost effect with the effects of attentional load, we suggest that temporal selection results in a temporally specific enhancement across modalities, tasks, and spatial locations. Moreover, the effects of temporal selection may be best observed when the attentional system is optimally tuned to the temporal dynamics of incoming stimuli. Several avenues of research motivated by the dual-task interaction model are then discussed. PMID:23730294

NASA cash boost for space firms

NASA Astrophysics Data System (ADS)

Gwynne, Peter

2012-09-01

NASA has awarded 1.1bn to three US firms to design and develop the "next generation of human spaceflight capabilities". Boeing, Sierra Nevada and Space Exploration Technologies (SpaceX), who will receive 460m, 212.5m and 440m respectively, will use the money to improve and test their systems intended to fly astronauts to the International Space Station (ISS) within the next five years.

Advocating a need for suitable breeding approaches to boost integrated pest management: a European perspective.

PubMed

Lamichhane, Jay Ram; Arseniuk, Edward; Boonekamp, Piet; Czembor, Jerzy; Decroocq, Veronique; Enjalbert, Jérome; Finckh, Maria R; Korbin, Małgorzata; Koppel, Mati; Kudsk, Per; Mesterhazy, Akos; Sosnowska, Danuta; Zimnoch-Guzowska, Ewa; Messéan, Antoine

2018-06-01

Currently, European farmers do not have access to sufficient numbers and diversity of crop species/varieties. This prevents them from designing cropping systems more resilient to abiotic and biotic stresses. Crop diversification is a key lever to reduce pest (pathogens, animal pests and weeds) pressures at all spatial levels from fields to landscapes. In this context, plant breeding should consist of: (1) increased efforts in the development of new or minor crop varieties to foster diversity in cropping systems, and (2) focus on more resilient varieties showing local adaptation. This new breeding paradigm, called here 'breeding for integrated pest management (IPM)', may boost IPM through the development of cultivars with tolerance or resistance to key pests, with the goal of reducing reliance on conventional pesticides. At the same time, this paradigm has legal and practical implications for future breeding programs, including those targeting sustainable agricultural systems. By putting these issues into the context, this article presents the key outcomes of a questionnaire survey and experts' views expressed during an EU workshop entitled 'Breeding for IPM in sustainable agricultural systems'. © 2017 Society of Chemical Industry. © 2017 Society of Chemical Industry.

Beyond the Boost: Measuring the Intrinsic Dipole of the Cosmic Microwave Background Using the Spectral Distortions of the Monopole and Quadrupole.

PubMed

Yasini, Siavash; Pierpaoli, Elena

2017-12-01

We present a general framework for the accurate spectral modeling of the low multipoles of the cosmic microwave background (CMB) as observed in a boosted frame. In particular, we demonstrate how spectral measurements of the low multipoles can be used to separate the motion-induced dipole of the CMB from a possible intrinsic dipole component. In a moving frame, the leakage of an intrinsic dipole moment into the CMB monopole and quadrupole induces spectral distortions with distinct frequency functions that, respectively, peak at 337 and 276 GHz. The leakage into the quadrupole moment also induces a geometrical distortion to the spatial morphology of this mode. The combination of these effects can be used to lift the degeneracy between the motion-induced dipole and any intrinsic dipole that the CMB might possess. Assuming the current peculiar velocity measurements, the leakage of an intrinsic dipole with an amplitude of ΔT=30  μK into the monopole and quadrupole moments will be detectable by a PIXIE-like experiment at ∼40  nK (2.5σ) and ∼130  nK (11σ) level at their respective peak frequencies.

Modernising patient clothing: a Florence Nightingale Foundation project.

PubMed

Fitzgerald, Christine

2017-04-27

Christine Fitzgerald, Matron at The Hillingdon Hospitals NHS Foundation Trust (currently on secondment) discusses a project to boost patient self-esteem and dignity through the clothing provided for them to wear.

Boosted food web productivity through ocean acidification collapses under warming.

PubMed

Goldenberg, Silvan U; Nagelkerken, Ivan; Ferreira, Camilo M; Ullah, Hadayet; Connell, Sean D

2017-10-01

Future climate is forecast to drive bottom-up (resource driven) and top-down (consumer driven) change to food web dynamics and community structure. Yet, our predictive understanding of these changes is hampered by an over-reliance on simplified laboratory systems centred on single trophic levels. Using a large mesocosm experiment, we reveal how future ocean acidification and warming modify trophic linkages across a three-level food web: that is, primary (algae), secondary (herbivorous invertebrates) and tertiary (predatory fish) producers. Both elevated CO 2 and elevated temperature boosted primary production. Under elevated CO 2 , the enhanced bottom-up forcing propagated through all trophic levels. Elevated temperature, however, negated the benefits of elevated CO 2 by stalling secondary production. This imbalance caused secondary producer populations to decline as elevated temperature drove predators to consume their prey more rapidly in the face of higher metabolic demand. Our findings demonstrate how anthropogenic CO 2 can function as a resource that boosts productivity throughout food webs, and how warming can reverse this effect by acting as a stressor to trophic interactions. Understanding the shifting balance between the propagation of resource enrichment and its consumption across trophic levels provides a predictive understanding of future dynamics of stability and collapse in food webs and fisheries production. © 2017 John Wiley & Sons Ltd.

Plant proteomics in India and Nepal: current status and challenges ahead.

PubMed

Deswal, Renu; Gupta, Ravi; Dogra, Vivek; Singh, Raksha; Abat, Jasmeet Kaur; Sarkar, Abhijit; Mishra, Yogesh; Rai, Vandana; Sreenivasulu, Yelam; Amalraj, Ramesh Sundar; Raorane, Manish; Chaudhary, Ram Prasad; Kohli, Ajay; Giri, Ashok Prabhakar; Chakraborty, Niranjan; Zargar, Sajad Majeed; Agrawal, Vishwanath Prasad; Agrawal, Ganesh Kumar; Job, Dominique; Renaut, Jenny; Rakwal, Randeep

2013-10-01

Plant proteomics has made tremendous contributions in understanding the complex processes of plant biology. Here, its current status in India and Nepal is discussed. Gel-based proteomics is predominantly utilized on crops and non-crops to analyze majorly abiotic (49 %) and biotic (18 %) stress, development (11 %) and post-translational modifications (7 %). Rice is the most explored system (36 %) with major focus on abiotic mainly dehydration (36 %) stress. In spite of expensive proteomics setup and scarcity of trained workforce, output in form of publications is encouraging. To boost plant proteomics in India and Nepal, researchers have discussed ground level issues among themselves and with the International Plant Proteomics Organization (INPPO) to act in priority on concerns like food security. Active collaboration may help in translating this knowledge to fruitful applications.

Fosamprenavir calcium plus ritonavir for HIV infection.

PubMed

Torres, Harrys A; Arduino, Roberto C

2007-06-01

Fosamprenavir is a protease inhibitor (PI) approved for the treatment of HIV-1 infection. Fosamprenavir is a prodrug of amprenavir developed to reduce the pill burden yet maintain the unique resistance pattern and efficacy associated with amprenavir. In a head-to-head, noninferiority trial in antiretroviral treatment-naive HIV-infected patients, the antiviral efficacy and tolerability of ritonavir-boosted fosamprenavir was not inferior to ritonavir-boosted lopinavir, when the PIs were combined with two other nucleoside reverse transcriptase inhibitors. There are fewer studies published about fosamprenavir use in antiretroviral treatment-experienced HIV-infected patients. The high genetic barrier to the development of resistance to fosamprenavir and the low level of cross-resistance between ritonavir-boosted fosamprenavir and other PI regimens are notable. As with amprenavir, gastrointestinal disturbance and rash are the most frequent short-term treatment-limiting events with fosamprenavir. Treatment with ritonavir-boosted fosamprenavir can produce a durable response. To date, fosamprenavir is one of the recommended preferred PI components for the treatment of antiretroviral-naive HIV-infected patients.

Vaccine strategies against Babesia bovis based on prime-boost immunizations in mice with modified vaccinia Ankara vector and recombinant proteins.

PubMed

Jaramillo Ortiz, José Manuel; Del Médico Zajac, María Paula; Zanetti, Flavia Adriana; Molinari, María Paula; Gravisaco, María José; Calamante, Gabriela; Wilkowsky, Silvina Elizabeth

2014-08-06

In this study, a recombinant modified vaccinia virus Ankara vector expressing a chimeric multi-antigen was obtained and evaluated as a candidate vaccine in homologous and heterologous prime-boost immunizations with a recombinant protein cocktail. The chimeric multi-antigen comprises immunodominant B and T cell regions of three Babesia bovis proteins. Humoral and cellular immune responses were evaluated in mice to compare the immunogenicity induced by different immunization schemes. The best vaccination scheme was achieved with a prime of protein cocktail and a boost with the recombinant virus. This scheme induced high level of specific IgG antibodies and secreted IFN and a high degree of activation of IFNγ(+) CD4(+) and CD8(+) specific T cells. This is the first report in which a novel vaccine candidate was constructed based on a rationally designed multi-antigen and evaluated in a prime-boost regime, optimizing the immune response necessary for protection against bovine babesiosis. Copyright © 2014 Elsevier Ltd. All rights reserved.

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

Clark, Hamish A.; Iwanus, Nikolas; Lewis, Geraint F.

The existence of substructure in halos of annihilating dark matter would be expected to substantially boost the rate at which annihilation occurs. Ultracompact minihalos of dark matter (UCMHs) are one of the more extreme examples of this. The boosted annihilation can inject significant amounts of energy into the gas of a galaxy over its lifetime. Here we determine the impact of the boost factor from UCMH substructure on the heating of galactic gas in a Milky Way-type galaxy, by means of N-body simulation. If 1% of the dark matter exists as UCMHs, the corresponding boost factor can be of ordermore » 10{sup 5}. For reasonable values of the relevant parameters (annihilation cross section 3×10{sup −26} cm{sup 3} s{sup −1}, dark matter mass 100 GeV, 10% heating efficiency), we show that the presence of UCMHs at the 0.1% level would inject enough energy to eject significant amounts of gas from the halo, potentially preventing star formation within ∼1 kpc of the halo centre.« less

Modeling Effects of Temperature, Soil, Moisture, Nutrition and Variety As Determinants of Severity of Pythium Damping-Off and Root Disease in Subterranean Clover

PubMed Central

You, Ming P.; Rensing, Kelly; Renton, Michael; Barbetti, Martin J.

2017-01-01

Subterranean clover (Trifolium subterraneum) is a critical pasture legume in Mediterranean regions of southern Australia and elsewhere, including Mediterranean-type climatic regions in Africa, Asia, Australia, Europe, North America, and South America. Pythium damping-off and root disease caused by Pythium irregulare is a significant threat to subterranean clover in Australia and a study was conducted to define how environmental factors (viz. temperature, soil type, moisture and nutrition) as well as variety, influence the extent of damping-off and root disease as well as subterranean clover productivity under challenge by this pathogen. Relationships were statistically modeled using linear and generalized linear models and boosted regression trees. Modeling found complex relationships between explanatory variables and the extent of Pythium damping-off and root rot. Linear modeling identified high-level (4 or 5-way) significant interactions for each dependent variable (dry shoot and root weight, emergence, tap and lateral root disease index). Furthermore, all explanatory variables (temperature, soil, moisture, nutrition, variety) were found significant as part of some interaction within these models. A significant five-way interaction between all explanatory variables was found for both dry shoot and root dry weights, and a four way interaction between temperature, soil, moisture, and nutrition was found for both tap and lateral root disease index. A second approach to modeling using boosted regression trees provided support for and helped clarify the complex nature of the relationships found in linear models. All explanatory variables showed at least 5% relative influence on each of the five dependent variables. All models indicated differences due to soil type, with the sand-based soil having either higher weights, greater emergence, or lower disease indices; while lowest weights and less emergence, as well as higher disease indices, were found for loam soil and low temperature. There was more severe tap and lateral root rot disease in higher moisture situations. PMID:29184544

Boosted dark matter signals uplifted with self-interaction

DOE PAGES

Kong, Kyoungchul; Mohlabeng, Gopolang; Park, Jong -Chul

2015-04-01

We explore detection prospects of a non-standard dark sector in the context of boosted dark matter. We focus on a scenario with two dark matter particles of a large mass difference, where the heavier candidate is secluded and interacts with the standard model particles only at loops, escaping existing direct and indirect detection bounds. Yet its pair annihilation in the galactic center or in the Sun may produce boosted stable particles, which could be detected as visible Cherenkov light in large volume neutrino detectors. In such models with multiple candidates, self-interaction of dark matter particles is naturally utilized in themore » assisted freeze-out mechanism and is corroborated by various cosmological studies such as N-body simulations of structure formation, observations of dwarf galaxies, and the small scale problem. We show that self-interaction of the secluded (heavier) dark matter greatly enhances the capture rate in the Sun and results in promising signals at current and future experiments. We perform a detailed analysis of the boosted dark matter events for Super-Kamiokande, Hyper-Kamiokande and PINGU, including notable effects such as evaporation due to self-interaction and energy loss in the Sun.« less

Boosted dark matter signals uplifted with self-interaction

NASA Astrophysics Data System (ADS)

Kong, Kyoungchul; Mohlabeng, Gopolang; Park, Jong-Chul

2015-04-01

We explore detection prospects of a non-standard dark sector in the context of boosted dark matter. We focus on a scenario with two dark matter particles of a large mass difference, where the heavier candidate is secluded and interacts with the standard model particles only at loops, escaping existing direct and indirect detection bounds. Yet its pair annihilation in the galactic center or in the Sun may produce boosted stable particles, which could be detected as visible Cherenkov light in large volume neutrino detectors. In such models with multiple candidates, self-interaction of dark matter particles is naturally utilized in the assisted freeze-out mechanism and is corroborated by various cosmological studies such as N-body simulations of structure formation, observations of dwarf galaxies, and the small scale problem. We show that self-interaction of the secluded (heavier) dark matter greatly enhances the capture rate in the Sun and results in promising signals at current and future experiments. We perform a detailed analysis of the boosted dark matter events for Super-Kamiokande, Hyper-Kamiokande and PINGU, including notable effects such as evaporation due to self-interaction and energy loss in the Sun.

Uncovering potential 'herbal probiotics' in Juzen-taiho-to through the study of associated bacterial populations.

PubMed

Montenegro, Diego; Kalpana, Kriti; Chrissian, Christine; Sharma, Ashutosh; Takaoka, Anna; Iacovidou, Maria; Soll, Clifford E; Aminova, Olga; Heguy, Adriana; Cohen, Lisa; Shen, Steven; Kawamura, Akira

2015-02-01

Juzen-taiho-to (JTT) is an immune-boosting formulation of ten medicinal herbs. It is used clinically in East Asia to boost the human immune functions. The active factors in JTT have not been clarified. But, existing evidence suggests that lipopolysaccharide (LPS)-like factors contribute to the activity. To examine this possibility, JTT was subjected to a series of analyses, including high resolution mass spectrometry, which suggested the presence of structural variants of LPS. This finding opened a possibility that JTT contains immune-boosting bacteria. As the first step to characterize the bacteria in JTT, 16S ribosomal RNA sequencing was carried out for Angelica sinensis (dried root), one of the most potent immunostimulatory herbs in JTT. The sequencing revealed a total of 519 bacteria genera in A. sinensis. The most abundant genus was Rahnella, which is widely distributed in water and plants. The abundance of Rahnella appeared to correlate with the immunostimulatory activity of A. sinensis. In conclusion, the current study provided new pieces of evidence supporting the emerging theory of bacterial contribution in immune-boosting herbs. Copyright © 2014 Elsevier Ltd. All rights reserved.

Single-stage three-phase boost power factor correction circuit for AC-DC converter

NASA Astrophysics Data System (ADS)

Azazi, Haitham Z.; Ahmed, Sayed M.; Lashine, Azza E.

2018-01-01

This article presents a single-stage three-phase power factor correction (PFC) circuit for AC-to-DC converter using a single-switch boost regulator, leading to improve the input power factor (PF), reducing the input current harmonics and decreasing the number of required active switches. A novel PFC control strategy which is characterised as a simple and low-cost control circuit was adopted, for achieving a good dynamic performance, unity input PF, and minimising the harmonic contents of the input current, at which it can be applied to low/medium power converters. A detailed analytical, simulation and experimental studies were therefore conducted. The effectiveness of the proposed controller algorithm is validated by the simulation results, which were carried out using MATLAB/SIMULINK environment. The proposed system is built and tested in the laboratory using DSP-DS1104 digital control board for an inductive load. The results revealed that the total harmonic distortion in the supply current was very low. Finally, a good agreement between simulation and experimental results was achieved.

40 CFR 81.339 - Pennsylvania.

Code of Federal Regulations, 2010 CFR

2010-07-01

... County Fayette County Forest County Franklin County Fulton County Greene County Huntingdon County Indiana... Elk County Unclassifiable/Attainment Forest County Unclassifiable/Attainment Jefferson County... Philadelphia-Wilmington-Atlantic City, PA-NJ-MD-DE: Bucks County Nonattainment Subpart 2/Moderate. Chester...

9. FIRST FLOOR, ENTRY HALL, LOOKING SOUTHWEST TOWARDS FRONT ENTRY ...

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

9. FIRST FLOOR, ENTRY HALL, LOOKING SOUTHWEST TOWARDS FRONT ENTRY WITH OPEN DOORWAY TO WINDER STAIRWAY ON RIGHT - Open Gate Farm, House, Ridge Road, 1 mile East of Elephant Road, Perkasie, Bucks County, PA

The big-bang-for-your-buck theory.

PubMed

Lucas, H C; Weill, P; Cox, S

1993-01-01

Do it right, and your investment in information technology can have all sorts of strategic payoffs. Do it wrong, and you'll be paying, dearly, for nothing. Here's a guide to evaluating IT and measuring its impact.

8. INTERIOR VIEW, FIRST FLOOR, NORTHEAST ROOM, EAST WALL, ORIGINAL ...

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

8. INTERIOR VIEW, FIRST FLOOR, NORTHEAST ROOM, EAST WALL, ORIGINAL KITCHEN FIREPLACE AND BAKE OVEN, WITH SCALE - Edgemont, 212 Bridgetown Pike, 1/4 mile East of PA 413 (Middletown Township), Langhorne, Bucks County, PA

3. INTERIOR PERSPECTIVE VIEW OF NORTHEAST AND NORTHWEST WALLS, SHOWING ...

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

3. INTERIOR PERSPECTIVE VIEW OF NORTHEAST AND NORTHWEST WALLS, SHOWING COOK FIREPLACE WITH BAKE OVEN TO REAR, WITH SCALE - High Farm, Kitchen, Creek Road, 1 mile East of Easton Road, Pipersville, Bucks County, PA

37. PRESSING TILES FROM PLASTER MOLDS, USING A HAND PRESS ...

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

37. PRESSING TILES FROM PLASTER MOLDS, USING A HAND PRESS CONSTRUCTED IN 1986. - Moravian Pottery & Tile Works, Southwest side of State Route 313 (Swamp Road), Northwest of East Court Street, Doylestown, Bucks County, PA

73. TILE WORKS FROM SOUTHEAST, c. 1920. JACOB FRANK COLLECTION ...

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

73. TILE WORKS FROM SOUTHEAST, c. 1920. JACOB FRANK COLLECTION (MISC 319), SL/BCHS. - Moravian Pottery & Tile Works, Southwest side of State Route 313 (Swamp Road), Northwest of East Court Street, Doylestown, Bucks County, PA

74. TILE WORKS COURTYARD, FROM SOUTH, c. 1915. FONTHILL MANUSCRIPTS. ...

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

74. TILE WORKS COURTYARD, FROM SOUTH, c. 1915. FONTHILL MANUSCRIPTS. SL/SCHS. UNCATALOGED POSTCARD. - Moravian Pottery & Tile Works, Southwest side of State Route 313 (Swamp Road), Northwest of East Court Street, Doylestown, Bucks County, PA

71. TILE WORKS FROM NORTHWEST, 191215. SL/BCHS, POSTCARD SN035. ...

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

71. TILE WORKS FROM NORTHWEST, 1912-15. SL/BCHS, POSTCARD SN-035. - Moravian Pottery & Tile Works, Southwest side of State Route 313 (Swamp Road), Northwest of East Court Street, Doylestown, Bucks County, PA

Impedance Matching Antenna-Integrated High-Efficiency Energy Harvesting Circuit

PubMed Central

Shinki, Yuharu; Shibata, Kyohei; Mansour, Mohamed

2017-01-01

This paper describes the design of a high-efficiency energy harvesting circuit with an integrated antenna. The circuit is composed of series resonance and boost rectifier circuits for converting radio frequency power into boosted direct current (DC) voltage. The measured output DC voltage is 5.67 V for an input of 100 mV at 900 MHz. Antenna input impedance matching is optimized for greater efficiency and miniaturization. The measured efficiency of this antenna-integrated energy harvester is 60% for −4.85 dBm input power and a load resistance equal to 20 kΩ at 905 MHz. PMID:28763043

Impedance Matching Antenna-Integrated High-Efficiency Energy Harvesting Circuit.

PubMed

Shinki, Yuharu; Shibata, Kyohei; Mansour, Mohamed; Kanaya, Haruichi

2017-08-01

This paper describes the design of a high-efficiency energy harvesting circuit with an integrated antenna. The circuit is composed of series resonance and boost rectifier circuits for converting radio frequency power into boosted direct current (DC) voltage. The measured output DC voltage is 5.67 V for an input of 100 mV at 900 MHz. Antenna input impedance matching is optimized for greater efficiency and miniaturization. The measured efficiency of this antenna-integrated energy harvester is 60% for -4.85 dBm input power and a load resistance equal to 20 kΩ at 905 MHz.

Evaluation of In Vitro Cross-Reactivity to Avian H5N1 and Pandemic H1N1 2009 Influenza Following Prime Boost Regimens of Seasonal Influenza Vaccination in Healthy Human Subjects: A Randomised Trial

DTIC Science & Technology

2013-03-26

virus (IIV) vaccine (dose 0.5 mL intramuscularly, purchased in Thailand from Sanofi Pasteur). Both vaccines contained the three strains for the 2009/10...H1N1 2009 Influenza Following Prime Boost Regimens of Seasonal Influenza Vaccination in Healthy Human Subjects: A Randomised Trial. 5a. CONTRACT NUMBER...reported by WHO since 2003 [1]. Current seasonal trivalent influenza vaccines rely on predicted antigens based on the previous season’s circulating

Successful practices in title III implementation. Chemical Emergency Preparedness and Prevention Technical Assistance Bulletin. Cameron County, Texas; Bucks County, Pennsylvania; Harford County, Maryland; Dallas County, Texas. Series 6, Number 7

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

Not Available

This is another in a series of bulletins EPA is issuing to provide examples of implementation programs and strategies of the Emergency Planning and Community Right-to-Know Act of 1986, known as Title III, that are innovative or have proven effective. The purpose of these bulletins is to share information on successful practices with Local Emergency Planning Committees (LEPCs), State Emergency Response Commissions (SERCs), fire departments, and other Title III implementing agencies throughout the country in the hope that such information will prove useful to other SERCs and LEPCs as their programs develop and evolve. The bulletin discusses Title III implementationmore » for Cameron County in Texas, Bucks County in Pennsylvania, Harford County in Maryland, and Dallas County in Texas.« less

Sliding mode controller with modified sliding function for DC-DC Buck Converter.

PubMed

Naik, B B; Mehta, A J

2017-09-01

This article presents design of Sliding Mode Controller with proportional integral type sliding function for DC-DC Buck Converter for the controlled power supply. The converter with conventional sliding mode controller results in a steady state error in load voltage. The proposed modified sliding function improves the steady state and dynamic performance of the Convertor and facilitates better choices of controller tuning parameters. The conditions for existence of sliding modes for proposed control scheme are derived. The stability of the closed loop system with proposed sliding mode control is proved and improvement in steady state performance is exemplified. The idea of adaptive tuning for the proposed controller to compensate load variations is outlined. The comparative study of conventional and proposed control strategy is presented. The efficacy of the proposed strategy is endowed by the simulation and experimental results. Copyright © 2017 ISA. Published by Elsevier Ltd. All rights reserved.

A prediction model of short-term ionospheric foF2 based on AdaBoost

NASA Astrophysics Data System (ADS)

Zhao, Xiukuan; Ning, Baiqi; Liu, Libo; Song, Gangbing

2014-02-01

In this paper, the AdaBoost-BP algorithm is used to construct a new model to predict the critical frequency of the ionospheric F2-layer (foF2) one hour ahead. Different indices were used to characterize ionospheric diurnal and seasonal variations and their dependence on solar and geomagnetic activity. These indices, together with the current observed foF2 value, were input into the prediction model and the foF2 value at one hour ahead was output. We analyzed twenty-two years' foF2 data from nine ionosonde stations in the East-Asian sector in this work. The first eleven years' data were used as a training dataset and the second eleven years' data were used as a testing dataset. The results show that the performance of AdaBoost-BP is better than those of BP Neural Network (BPNN), Support Vector Regression (SVR) and the IRI model. For example, the AdaBoost-BP prediction absolute error of foF2 at Irkutsk station (a middle latitude station) is 0.32 MHz, which is better than 0.34 MHz from BPNN, 0.35 MHz from SVR and also significantly outperforms the IRI model whose absolute error is 0.64 MHz. Meanwhile, AdaBoost-BP prediction absolute error at Taipei station from the low latitude is 0.78 MHz, which is better than 0.81 MHz from BPNN, 0.81 MHz from SVR and 1.37 MHz from the IRI model. Finally, the variety characteristics of the AdaBoost-BP prediction error along with seasonal variation, solar activity and latitude variation were also discussed in the paper.

Comparison of the immunogenicity and protection against bovine tuberculosis following immunization by BCG-priming and boosting with adenovirus or protein based vaccines.

PubMed

Dean, G; Whelan, A; Clifford, D; Salguero, F J; Xing, Z; Gilbert, S; McShane, H; Hewinson, R G; Vordermeier, M; Villarreal-Ramos, B

2014-03-05

There is a requirement for vaccines or vaccination strategies that confer better protection against TB than the current live attenuated Mycobacterium bovis Bacillus Calmette-Guerin (BCG) vaccine for use in cattle. Boosting with recombinant viral vectors expressing mycobacterial proteins, such as Ag85A, has shown a degree of promise as a strategy for improving on the protection afforded by BCG. Experiments in small animal models have indicated that broadening the immune response to include mycobacterial antigens other than Ag85A, such as Rv0288, induced by boosting with Ad5 constructs has a direct effect on the protection afforded against TB. Here, we compared the immunogenicity and protection against challenge with M. bovis afforded by boosting BCG-vaccinated cattle with a human type 5 (Ad5)-based vaccine expressing the mycobacterial antigens Ag85A (Ad5-85A); or Ag85A, Rv0251, Rv0287 and Rv0288 (Ad5-TBF); or with protein TBF emulsified in adjuvant (Adj-TBF). Boosting with TBF broaden the immune response. The kinetics of Ad5-TBF and Adj-TBF were shown to be different, with effector T cell responses from the latter developing more slowly but being more durable than those induced by Ad5-TBF. No increase in protection compared to BCG alone was afforded by Ad5-TBF or Adj-TBF by gross pathology or bacteriology. Using histopathology, as a novel parameter of protection, we show that boosting BCG vaccinated cattle with Ad5-85A induced significantly better protection than BCG alone. Crown Copyright © 2013. Published by Elsevier Ltd. All rights reserved.