Optical single side-band Nyquist PAM-4 transmission using dual-drive MZM modulation and direct detection.

PubMed

Zhu, Mingyue; Zhang, Jing; Yi, Xingwen; Ying, Hao; Li, Xiang; Luo, Ming; Song, Yingxiong; Huang, Xiatao; Qiu, Kun

2018-03-19

We present the design and optimization of the optical single side-band (SSB) Nyquist four-level pulse amplitude modulation (PAM-4) transmission using dual-drive Mach-Zehnder modulator (DDMZM)modulation and direct detection (DD), aiming at the C-band cost-effective, high-speed and long-distance transmission. At the transmitter, the laser line width should be small to avoid the phase noise to amplitude noise conversion and equalization-enhanced phase noise due to the large chromatic dispersion (CD). The optical SSB signal is generated after optimizing the optical modulation index (OMI) and hence the minimum phase condition which is required by the Kramers-Kronig (KK) receiver can also be satisfied. At the receiver, a simple AC-coupled photodiode (PD) is used and a virtual carrier is added for the KK operation to alleviate the signal-to-signal beating interference (SSBI).A Volterra filter (VF) is cascaded for remaining nonlinearities mitigation. When the fiber nonlinearity becomes significant, we elect to use an optical band-pass filter with offset filtering. It can suppress the simulated Brillouin scattering and the conjugated distortion by filtering out the imaging frequency components. With our design and optimization, we achieve single-channel, single polarization 102.4-Gb/s Nyquist PAM-4 over 800-km standard single-mode fiber (SSMF).

Dispersion induced power fading for radio frequency signals and its application for fast online PMD and CD monitoring

NASA Astrophysics Data System (ADS)

Ning, G.; Shum, P.

2007-06-01

We derive the expressions for the power fading including first-order polarization mode dispersion (PMD), chromatic dispersion, chirp parameter as well as polarization-dependent chromatic dispersion (PCD), which is dependent on the angle of precession of output state of polarization around the PMD vector. From the expression for radio frequency (RF) signals power fading, we get the average power fading for chromatic dispersion, chirp parameter, first-order PMD and PCD for both double sideband (DSB) modulation and single sideband (SSB) modulation. We also demonstrate a fast PMD and chromatic dispersion monitoring technology with reduced polarization-dependent gain. The measured results agree well with theoretical analysis.

Investigation of Analog Photonic Link Technology for Timing and Metrological Applications

DTIC Science & Technology

2015-05-18

same model bias tee in each case. Fig. 1.8: Measured residual single-sideband (SSB) phase noise for two amplifiers with various RF pads at...deflection at the AO output. The deflected signal is reflected onto a tilted diffraction grating and passed backed through the device to the output...Other TTD modulation mechanisms have been considered including fiber stretches (mechanical and piezoelectric ), electro-optic modulators (i.e

Experimental comparison of direct detection Nyquist SSB transmission based on silicon dual-drive and IQ Mach-Zehnder modulators with electrical packaging.

PubMed

Ruan, Xiaoke; Li, Ke; Thomson, David J; Lacava, Cosimo; Meng, Fanfan; Demirtzioglou, Iosif; Petropoulos, Periklis; Zhu, Yixiao; Reed, Graham T; Zhang, Fan

2017-08-07

We have designed and fabricated a silicon photonic in-phase-quadrature (IQ) modulator based on a nested dual-drive Mach-Zehnder structure incorporating electrical packaging. We have assessed its use for generating Nyquist-shaped single sideband (SSB) signals by operating it either as an IQ Mach-Zehnder modulator (IQ-MZM) or using just a single branch of the dual-drive Mach-Zehnder modulator (DD-MZM). The impact of electrical packaging on the modulator bandwidth is also analyzed. We demonstrate 40 Gb/s (10Gbaud) 16-ary quadrature amplitude modulation (16-QAM) Nyquist-shaped SSB transmission over 160 km standard single mode fiber (SSMF). Without using any chromatic dispersion compensation, the bit error rates (BERs) of 5.4 × 10 -4 and 9.0 × 10 -5 were measured for the DD-MZM and IQ-MZM, respectively, far below the 7% hard-decision forward error correction threshold. The performance difference between IQ-MZM and DD-MZM is most likely due to the non-ideal electrical packaging. Our work is the first experimental comparison between silicon IQ-MZM and silicon DD-MZM in generating SSB signals. We also demonstrate 50 Gb/s (12.5Gbaud) 16-QAM Nyquist-shaped SSB transmission over 320 km SSMF with a BER of 2.7 × 10 -3 . Both the silicon IQ-MZM and the DD-MZM show potential for optical transmission at metro scale and for data center interconnection.

Full duplex fiber link for alternative wired and wireless access based on SSB optical millimeter-wave with 4-PAM signal

NASA Astrophysics Data System (ADS)

Ma, Jianxin; Zhang, Junjie

2015-03-01

A novel full-duplex fiber-wireless link based on single sideband (SSB) optical millimeter (mm)-wave with 10 Gbit/s 4-pulse amplitude modulation (PAM) signal is proposed to provide alternative wired and 40 GHz wireless accesses for the user terminals. The SSB optical mm-wave with 4-PAM signal consists of two tones: one bears the 4-PAM signal and the other is unmodulated with high power. After transmission over the fiber to the hybrid optical network unit (HONU), the SSB optical mm-wave signal can be decomposed by fiber Bragg gratings (FBGs) as the SSB optical mm-wave signal with reduced carrier-to-sideband ratio (the baseband 4-PAM optical signal) and the uplink optical carrier for the wireless (wired) access. This makes the HONU free from the laser source. For the uplink, since the wireless access signal is converted to the baseband by power detection, both the transmitter in the HONU and the receiver in optical line terminal (OLT) are co-shared for both wireless and wired accesses, which makes the full duplex link much simpler. In our scheme, the optical electrical field of the square-root increment level 4-PAM signal assures an equal level spacing receiving for both the downlink wired and wireless accesses. Since the downlink wireless signal is down-converted to the baseband by power detection, RF local oscillator is unnecessary. To confirm the feasibility of our proposed scheme, a simulation full duplex link with 40 GHz SSB optical mm-wave with 10 Gbit/s 4-PAM signal is built. The simulation results show that both down- and up-links for either wired or wireless access can keep good performance even if the link length of the SSMF is extended to 40 km.

A novel wavelength reused bidirectional RoF-WDM-PON architecture to mitigate reflection and Rayleigh backscattered noise in multi-Gb/s m-QAM OFDM SSB upstream and downstream transmission over a single fiber

NASA Astrophysics Data System (ADS)

Patel, Dhananjay; Dalal, U. D.

2017-05-01

A novel m-QAM Orthogonal Frequency Division Multiplexing (OFDM) Single Sideband (SSB) architecture is proposed for centralized light source (CLS) bidirectional Radio over Fiber (RoF) - Wavelength Division Multiplexing (WDM) - Passive Optical Network (PON). In bidirectional transmission with carrier reuse over the single fiber, the Rayleigh Backscattering (RB) noise and reflection (RE) interferences from optical components can seriously deteriorate the transmission performance of the fiber optic systems. These interferometric noises can be mitigated by utilizing the optical modulation schemes at the Optical Line Terminal (OLT) and Optical Network Unit (ONU) such that the spectral overlap between the optical data spectrum and the RB and RE noise is minimum. A mathematical model is developed for the proposed architecture to accurately measure the performance of the transmission system and also to analyze the effect of interferometric noise caused by the RB and RE. The model takes into the account the different modulation schemes employed at the OLT and the ONU using a Mach Zehnder Modulator (MZM), the optical launch power and the bit-rates of the downstream and upstream signals, the gain of the amplifiers at the OLT and the ONU, the RB-RE noise, chromatic dispersion of the single mode fiber and optical filter responses. In addition, the model analyzes all the components of the RB-RE noise such as carrier RB, signal RB, carrier RE and signal RE, thus providing the complete representation of all the physical phenomena involved. An optical m-QAM OFDM SSB signal acts as a test signal to validate the model which provides excellent agreement with simulation results. The SSB modulation technique using the MZM at the OLT and the ONU differs in the data transmission technique that takes place through the first-order higher and the lower optical sideband respectively. This spectral gap between the downstream and upstream signals reduces the effect of Rayleigh backscattering and discrete reflections.

Experimental demonstration of an efficient hybrid equalizer for short-reach optical SSB systems

NASA Astrophysics Data System (ADS)

Zhu, Mingyue; Ying, Hao; Zhang, Jing; Yi, Xingwen; Qiu, Kun

2018-02-01

We propose an efficient enhanced hybrid equalizer combining the feed forward equalization (FFE) with a modified Volterra filter to mitigate the linear and nonlinear interference for the short-reach optical single side-band (SSB) system. The optical SSB signal is generated by a relatively low-cost dual-drive Mach-Zehnder modulator (DDMZM). The two driving signals are a pair of Hilbert signals with Nyquist pulse-shaped four-level pulse amplitude modulation (NPAM-4). After the fiber transmission, the neighboring received symbols are strongly correlated due to the pulse spreading in time domain caused by the chromatic dispersion (CD). At the receiver equalization stage, the FFE followed by higher order terms of modified Volterra filter, which utilizes the forward and backward neighboring symbols to construct the kernels with strong correlation, are used as an enhanced hybrid equalizer to mitigate the inter symbol interference (ISI) and nonlinear distortion due to the interaction of the CD and the square-law detection. We experimentally demonstrate that the optical SSB NPAM-4 signal of 40 Gb/s transmitting over 80 km standard single mode fiber (SSMF) with a bit-error-rate (BER) of 7 . 59 × 10-4.

Identification and mitigation of interference sources present in SSB-based wireless MRI receiver arrays

PubMed Central

Riffe, Matthew J.; Twieg, Michael D.; Gudino, Natalia; Blumenthal, Colin J.; Heilman, Jeremy A.; Griswold, Mark A.

2013-01-01

Purpose Single sideband amplitude modulation (SSB) is an appealing platform for highly parallel wireless MRI detector arrays because the spacing between channels is ideally limited only by the MRI signal bandwidth. However this assumes that no other sources of interference are present outside that bandwidth. This work investigates the practical interference between multiple SSB-encoded MRI signals. Methods Noise from coil preamplifiers and carrier bleed-through are identified as sources of interference. Two different SSB systems were designed for 1.5T with different noise filtering properties. We show how the differences between the filtered noise profiles impact the received MR signal’s dynamic range (DRsig) and image signal-to-noise ratio (SNR) through simulation, bench measurements, and phantom imaging experiments. Results When operating individually in the MR scanner, both SSB systems were shown to minimally impact the original DRsig and SNR. On the other hand, when all eight channels were operating simultaneously, an average SNR loss was observed to be 12% in the one system, while a second system with more complex filtering was able to achieve a 3% loss in SNR. Conclusion Successful wireless transmission of multiple SSB-encoded MRI signals is possible as long as channel interference is properly managed through design and simulation. PMID:23413242

Swept optical SSB-SC modulation technique for high-resolution large-dynamic-range static strain measurement using FBG-FP sensors.

PubMed

Huang, Wenzhu; Zhang, Wentao; Li, Fang

2015-04-01

This Letter presents a static strain demodulation technique for FBG-FP sensors using a suppressed carrier LiNbO(3) (LN) optical single sideband (SSB-SC) modulator. A narrow-linewidth tunable laser source is generated by driving the modulator using a linear chirp signal. Then this tunable single-frequency laser is used to interrogate the FBG-FP sensors with the Pound-Drever-Hall (PDH) technique, which is beneficial to eliminate the influence of light intensity fluctuation of the modulator at different tuning frequencies. The static strain is demodulated by calculating the wavelength difference of the PDH signals between the sensing FBG-FP sensor and the reference FBG-FP sensor. As an experimental result using the modulator, the linearity (R²) of the time-frequency response increases from 0.989 to 0.997, and the frequency-swept range (dynamic range) increases from hundreds of MHz to several GHz compared with commercial PZT-tunable lasers. The high-linearity time-wavelength relationship of the modulator is beneficial for improving the strain measurement resolution, as it can solve the problem of the frequency-swept nonlinearity effectively. In the laboratory test, a 0.67 nanostrain static strain resolution, with a 6 GHz dynamic range, is demonstrated.

WDM-PON access network with lightwave source centralized full-duplex link based on SSB-OOFDM for wired and 60 GHz band wireless alternative accesses

NASA Astrophysics Data System (ADS)

Ma, Jianxin; Wang, Zhao; Zheng, Guoli

2014-04-01

A novel lightwave centralized full-duplex WDM-PON access network based on single sideband optical orthogonal frequency-division multiplexing (SSB-OOFDM) is proposed for providing wired and 60-GHz band wireless accesses alternately. At the OLT, the multi-channels with 10-Gb/s 4-QAM-RF-OFDM signals are SSB modulated on the optical local oscillators (OLOs). At the RN, one OOFDM signal along with two OLOs is abstracted and switched to the corresponding HONU, where the signal can be downconverted to the 10-GHz or 60-GHz band RF-OFDM signal by one OLO for wired or wireless access, while the other one is used to bear the uplink signal. Since the HONU is free from the light sources, the system complexity and cost are reduced. Full duplex transmission over 25 km fiber have been demonstrated that the error vector magnitude (EVM) of the down- and up-link signals are much below the FEC limit for both the wired and 60-GHz band wireless access services.

A polarization-division multiplexing SSB-OFDM system with beat interference cancellation receivers

NASA Astrophysics Data System (ADS)

Yang, Peiling; Ma, Jianxin; Zhang, Junyi

2018-06-01

In this paper, we have proposed a polarization-division multiplexing (PDM) single-sideband optical orthogonal frequency division multiplexing (SSB-OOFDM) scheme with signal-signal beat interference cancellation receivers with balanced detection (ICRBD). This system can double channel capacity and improve spectrum efficiency (SE) with the reduced guard band (GB) due to the PDM. Multiple input multiple output (MIMO) technique is used to solve polarization mode dispersion (PMD) associated with channel estimation and equalization. By simulation, we demonstrate the efficacy of the proposed technique for a 2 ×40 Gbit/s 16-QAM SSB-PDM-OOFDM system according to the error vector magnitude (EVM) and the constellation diagrams.

Simultaneously frequency down-conversion, independent multichannel phase shifting and zero-IF receiving using a phase modulator in a sagnac loop and balanced detection

NASA Astrophysics Data System (ADS)

Zhu, Zihang; Zhao, Shanghong; Li, Xuan; Lin, Tao; Hu, Dapeng

2018-03-01

Photonic microwave frequency down-conversion with independent multichannel phase shifting and zero-intermediate frequency (IF) receiving is proposed and demonstrated by simulation. By combined use of a phase modulator (PM) in a sagnac loop and an optical bandpass filter (OBPF), orthogonal polarized carrier suppression single sideband (CS-SSB) signals are obtained. By adjusting the polarization controllers (PCs) to introduce the phase difference in the optical domain and using balanced detection to eliminate the direct current components, the phase of the generated IF signal can be arbitrarily tuned. Besides, the radio frequency (RF) vector signal can be also frequency down-converted to baseband directly by choosing two quadrature channels. In the simulation, high gain and continuously tunable phase shifts over the 360 degree range are verified. Furthermore, 2.5 Gbit/s RF vector signals centered at 10 GHz with different modulation formats are successfully demodulated.

Device localization and dynamic scan plane selection using a wireless magnetic resonance imaging detector array.

PubMed

Riffe, Matthew J; Yutzy, Stephen R; Jiang, Yun; Twieg, Michael D; Blumenthal, Colin J; Hsu, Daniel P; Pan, Li; Gilson, Wesley D; Sunshine, Jeffrey L; Flask, Christopher A; Duerk, Jeffrey L; Nakamoto, Dean; Gulani, Vikas; Griswold, Mark A

2014-06-01

A prototype wireless guidance device using single sideband amplitude modulation (SSB) is presented for a 1.5T magnetic resonance imaging system. The device contained three fiducial markers each mounted to an independent receiver coil equipped with wireless SSB technology. Acquiring orthogonal projections of these markers determined the position and orientation of the device, which was used to define the scan plane for a subsequent image acquisition. Device localization and scan plane update required approximately 30 ms, so it could be interleaved with high temporal resolution imaging. Since the wireless device is used for localization and does not require full imaging capability, the design of the SSB wireless system was simplified by allowing an asynchronous clock between the transmitter and receiver. When coupled to a high readout bandwidth, the error caused by the lack of a shared frequency reference was quantified to be less than one pixel (0.78 mm) in the projection acquisitions. Image guidance with the prototype was demonstrated with a phantom where a needle was successfully guided to a target and contrast was delivered. The feasibility of active tracking with a wireless detector array is demonstrated. Wireless arrays could be incorporated into devices to assist in image-guided procedures. Copyright © 2013 Wiley Periodicals, Inc.

Device localization and dynamic scan plane selection using a wireless MRI detector array

PubMed Central

Riffe, Matthew J.; Yutzy, Stephen R.; Jiang, Yun; Twieg, Michael D.; Blumenthal, Colin J.; Hsu, Daniel P.; Pan, Li; Gilson, Wesley D.; Sunshine, Jeffrey L.; Flask, Christopher A.; Duerk, Jeffrey L.; Nakamoto, Dean; Gulani, Vikas; Griswold, Mark A.

2013-01-01

Purpose A prototype wireless guidance device using single sideband amplitude modulation (SSB) is presented for a 1.5T MRI system. Methods The device contained three fiducial markers each mounted to an independent receiver coil equipped with wireless SSB technology. Acquiring orthogonal projections of these markers determined the position and orientation of the device, which was used to define the scan plane for a subsequent image acquisition. Device localization and scan plane update required approximately 30 ms, so it could be interleaved with high temporal resolution imaging. Since the wireless device is used for localization and doesn’t require full imaging capability, the design of the SSB wireless system was simplified by allowing an asynchronous clock between the transmitter and receiver. Results When coupled to a high readout bandwidth, the error caused by the lack of a shared frequency reference was quantified to be less than one pixel (0.78 mm) in the projection acquisitions. Image-guidance with the prototype was demonstrated with a phantom where a needle was successfully guided to a target and contrast was delivered. Conclusion The feasibility of active tracking with a wireless detector array is demonstrated. Wireless arrays could be incorporated into devices to assist in image-guided procedures. PMID:23900921

Concurrent encoding of frequency and amplitude modulation in human auditory cortex: encoding transition.

PubMed

Luo, Huan; Wang, Yadong; Poeppel, David; Simon, Jonathan Z

2007-12-01

Complex natural sounds (e.g., animal vocalizations or speech) can be characterized by specific spectrotemporal patterns the components of which change in both frequency (FM) and amplitude (AM). The neural coding of AM and FM has been widely studied in humans and animals but typically with either pure AM or pure FM stimuli. The neural mechanisms employed to perceptually unify AM and FM acoustic features remain unclear. Using stimuli with simultaneous sinusoidal AM (at rate f(AM) = 37 Hz) and FM (with varying rates f(FM)), magnetoencephalography (MEG) is used to investigate the elicited auditory steady-state response (aSSR) at relevant frequencies (f(AM), f(FM), f(AM) + f(FM)). Previous work demonstrated that for sounds with slower FM dynamics (f(FM) < 5 Hz), the phase of the aSSR at f(AM) tracked the FM; in other words, AM and FM features were co-tracked and co-represented by "phase modulation" encoding. This study explores the neural coding mechanism for stimuli with faster FM dynamics (< or =30 Hz), demonstrating that at faster rates (f(FM) > 5 Hz), there is a transition from pure phase modulation encoding to a single-upper-sideband (SSB) response (at frequency f(AM) + f(FM)) pattern. We propose that this unexpected SSB response can be explained by the additional involvement of subsidiary AM encoding responses simultaneously to, and in quadrature with, the ongoing phase modulation. These results, using MEG to reveal a possible neural encoding of specific acoustic properties, demonstrate more generally that physiological tests of encoding hypotheses can be performed noninvasively on human subjects, complementing invasive, single-unit recordings in animals.

ALMA Band 5 receiver cartridge. Design, performance, and commissioning

NASA Astrophysics Data System (ADS)

Belitsky, V.; Bylund, M.; Desmaris, V.; Ermakov, A.; Ferm, S.-E.; Fredrixon, M.; Krause, S.; Lapkin, I.; Meledin, D.; Pavolotsky, A.; Rashid, H.; Shafiee, S.; Strandberg, M.; Sundin, E.; Aghdam, P. Yadranjee; Hesper, R.; Barkhof, J.; Bekema, M. E.; Adema, J.; Haan, R. de; Koops, A.; Boland, W.; Yagoubov, P.; Marconi, G.; Siringo, G.; Humphreys, E.; Tan, G. H.; Laing, R.; Testi, L.; Mroczkowski, T.; Wild, W.; Saini, K. S.; Bryerton, E.

2018-04-01

We describe the design, performance, and commissioning results for the new ALMA Band 5 receiver channel, 163-211 GHz, which is in the final stage of full deployment and expected to be available for observations in 2018. This manuscript provides the description of the new ALMA Band 5 receiver cartridge and serves as a reference for observers using the ALMA Band 5 receiver for observations. At the time of writing this paper, the ALMA Band 5 Production Consortium consisting of NOVA Instrumentation group, based in Groningen, NL, and GARD in Sweden have produced and delivered to ALMA Observatory over 60 receiver cartridges. All 60 cartridges fulfil the new more stringent specifications for Band 5 and demonstrate excellent noise temperatures, typically below 45 K single sideband (SSB) at 4 K detector physical temperature and below 35 K SSB at 3.5 K (typical for operation at the ALMA Frontend), providing the average sideband rejection better than 15 dB, and the integrated cross-polarization level better than -25 dB. The 70 warm cartridge assemblies, hosting Band 5 local oscillator and DC bias electronics, have been produced and delivered to ALMA by NRAO. The commissioning results confirm the excellent performance of the receivers.

Relative sideband amplitudes versus modulation index for common functions using frequency and phase modulation. [for design and testing of communication system

NASA Technical Reports Server (NTRS)

Stocklin, F.

1973-01-01

The equations defining the amplitude of sidebands resulting from either frequency modulation or phase modulation by either square wave, sine wave, sawtooth or triangular modulating functions are presented. Spectral photographs and computer generated tables of modulation index vs. relative sideband amplitudes are also included.

47 CFR 90.207 - Types of emissions.

Code of Federal Regulations, 2010 CFR

2010-10-01

... under this part, see § 2.201 of this chapter. (1) The first symbol indicates the type of modulation on the transmitter carrier. A—Amplitude modulation, double sideband with identical information on each sideband. F—Frequency modulation. G—Phase modulation. J—Single sideband with suppressed carrier. P...

Microfabricated high-bandpass foucault aperture for electron microscopy

DOEpatents

Glaeser, Robert; Cambie, Rossana; Jin, Jian

2014-08-26

A variant of the Foucault (knife-edge) aperture is disclosed that is designed to provide single-sideband (SSB) contrast at low spatial frequencies but retain conventional double-sideband (DSB) contrast at high spatial frequencies in transmission electron microscopy. The aperture includes a plate with an inner open area, a support extending from the plate at an edge of the open area, a half-circle feature mounted on the support and located at the center of the aperture open area. The radius of the half-circle portion of reciprocal space that is blocked by the aperture can be varied to suit the needs of electron microscopy investigation. The aperture is fabricated from conductive material which is preferably non-oxidizing, such as gold, for example.

Analysis of second order harmonic distortion due to transmitter non-linearity and chromatic and modal dispersion of optical OFDM SSB modulated signals in SMF-MMF fiber links

NASA Astrophysics Data System (ADS)

Patel, Dhananjay; Singh, Vinay Kumar; Dalal, U. D.

2017-01-01

Single mode fibers (SMF) are typically used in Wide Area Networks (WAN), Metropolitan Area Networks (MAN) and also find applications in Radio over Fiber (RoF) architectures supporting data transmission in Fiber to the Home (FTTH), Remote Antenna Units (RAUs), in-building networks etc. Multi-mode fibers (MMFs) with low cost, ease of installation and low maintenance are predominantly (85-90%) deployed in-building networks providing data access in local area networks (LANs). The transmission of millimeter wave signals through the SMF in WAN and MAN, along with the reuse of MMF in-building networks will not levy fiber reinstallation cost. The transmission of the millimeter waves experiences signal impairments due to the transmitter non-linearity and modal dispersion of the MMF. The MMF exhibiting large modal dispersion limits the bandwidth-length product of the fiber. The second and higher-order harmonics present in the optical signal fall within the system bandwidth. This causes degradation in the received signal and an unwanted radiation of power at the RAU. The power of these harmonics is proportional to the non-linearity of the transmitter and the modal dispersion of the MMF and should be maintained below the standard values as per the international norms. In this paper, a mathematical model is developed for Second-order Harmonic Distortion (HD2) generated due to non-linearity of the transmitter and chromatic-modal dispersion of the SMF-MMF optic link. This is also verified using a software simulation. The model consists of a Mach Zehnder Modulator (MZM) that generates two m-QAM OFDM Single Sideband (SSB) signals based on phase shift of the hybrid coupler (90° and 120°). Our results show that the SSB signal with 120° hybrid coupler has suppresses the higher-order harmonics and makes the system more robust against the HD2 in the SMF-MMF optic link.

Fiber-FSO/wireless convergent systems based on dual-polarization and one optical sideband transmission schemes

NASA Astrophysics Data System (ADS)

Huang, Xu-Hong; Lu, Hai-Han; Li, Chung-Yi; Wang, Yun-Chieh; Chang, Jen-Chieh; Jheng, Yu-Bo; Tsai, Wen-Shing

2018-06-01

A bidirectional fiber-free-space optical (FSO)/wireless convergent system that uses dual-polarization and one optical sideband transmission schemes for hybrid vestigial sideband (VSB)–four-level pulse amplitude modulation (PAM4)/millimeter-wave signal transmission is proposed and demonstrated. Using a dual-polarization scheme, one optical sideband that is modulated by a 56 Gb s‑1 VSB–PAM4 signal (x-polarization) and another optical sideband that is modulated by a 10 Gbps data stream (y-polarization) are separated and polarized orthogonally. One optical sideband modulated by a 10 Gbps data stream (y-polarization) is delivered to efficaciously suppress the dispersion-induced limitation due to a span of 40 km single-mode fiber (SMF) and the distortion due to the beating among multiple sidebands. The proposed bidirectional fiber-FSO/wireless convergent system is a prominent one for providing broadband integrated services, such as the Internet, telecommunication, and 5G mobile networks.

Optical pulse synthesis using brillouin selective sideband amplification

NASA Technical Reports Server (NTRS)

Yao, X. Steve (Inventor)

2002-01-01

Techniques for producing optical pulses based on Brillouin selective sideband amplification by using a common modulation control signal to modulate both a signal beam to produce multiple sideband signals and a single pump beam to produce multiple pump beams.

47 CFR 73.756 - System specifications for double-sideband (DBS) modulated emissions in the HF broadcasting service.

Code of Federal Regulations, 2010 CFR

2010-10-01

... 47 Telecommunication 4 2010-10-01 2010-10-01 false System specifications for double-sideband (DBS... Stations § 73.756 System specifications for double-sideband (DBS) modulated emissions in the HF... processing. If audio-frequency signal processing is used, the dynamic range of the modulating signal shall be...

A novel dipolar dephasing method for the slow magic angle turning experiment.

PubMed

Hu, J Z; Taylor, C M; Pugmire, R J; Grant, D M

2001-09-01

Complete suppression of the resonances from protonated carbons in a slow magic angle spinning experiment can be achieved using five dipolar dephasing (Five-DD) periods distributed in one rotor period. This produces a spectrum containing only the spinning sidebands (SSB) from the nonprotonated carbons. It is shown that the SSB patterns corresponding to the nonprotonated carbons are not distorted over a wide range of dipolar dephasing times. Hence, this method can be used to obtain reliable principal values of the chemical shift tensors for each nonprotonated carbon. The Five-DD method can be readily incorporated into isotropic-anisotropic 2D experiments such as FIREMAT and 2D-PASS to facilitate the measurement of the (13)C chemical shift tensors in complex systems. Copyright 2001 Academic Press.

Precision and broadband frequency swept laser source based on high-order modulation-sideband injection-locking.

PubMed

Wei, Fang; Lu, Bin; Wang, Jian; Xu, Dan; Pan, Zhengqing; Chen, Dijun; Cai, Haiwen; Qu, Ronghui

2015-02-23

A precision and broadband laser frequency swept technique is experimentally demonstrated. Using synchronous current compensation, a slave diode laser is dynamically injection-locked to a specific high-order modulation-sideband of a narrow-linewidth master laser modulated by an electro-optic modulator (EOM), whose driven radio frequency (RF) signal can be agilely, precisely controlled by a frequency synthesizer, and the high-order modulation-sideband enables multiplied sweep range and tuning rate. By using 5th order sideband injection-locking, the original tuning range of 3 GHz and tuning rate of 0.5 THz/s is multiplied by 5 times to 15 GHz and 2.5 THz/s respectively. The slave laser has a 3 dB-linewidth of 2.5 kHz which is the same to the master laser. The settling time response of a 10 MHz frequency switching is 2.5 µs. By using higher-order modulation-sideband and optimized experiment parameters, an extended sweep range and rate could be expected.

Four-amplitude shift keying-single sideband millimeter-wave signal generation with frequency sextupling based on optical phase modulation

NASA Astrophysics Data System (ADS)

Wu, Peng; Ma, Jianxin

2017-03-01

We have proposed and demonstrated a scheme to generate a frequency-sextupling amplitude shift keying (ASK)-single sideband optical millimeter (mm)-wave signal with high dispersion tolerance based on an optical phase modulator (PM) by ably using the-4th-order and +2nd-order sidebands of the optical modulation. The ASK radio frequency signal, superposed by a local oscillator with the same frequency, modulates the lightwave via an optical PM with proper voltage amplitudes, the +2nd-order sideband carries the ASK signal with a constant slope while the -4th-order sideband maintains constant amplitude. These two sidebands can be abstracted by a wavelength selective switch to form a dual-tone optical mm-wave with only one tone carrying the ASK signal. As only one tone bears the ASK signal while the other tone is unmodulated, the generated dual-tone optical mm-wave signal has high dispersion tolerance.

Compact transmission system using single-sideband modulation of light for quantum cryptography.

PubMed

Duraffourg, L; Merolla, J M; Goedgebuer, J P; Mazurenko, Y; Rhodes, W T

2001-09-15

We report a new transmission that can be used for quantum key distribution. The system uses single-sideband-modulated light in an implementation of the BB84 quantum cryptography protocol. The system is formed by two integrated unbalanced Mach-Zehnder interferometers and is based on interference between phase-modulated sidebands in the spectral domain. Experiments show that high interference visibility can be obtained.

Translations on Telecommunications Policy, Research and Development No. 18

DTIC Science & Technology

1977-10-27

Rico and El Dorado, with an alternative route toward Brazil, through Foz do Iguazu and the enlarged radio connection between Buenos Aires and Campo ...nor the more recently studied infrasound. By sound, in and of itself, we understand noise, music and speech. The first of these, about which there...is used for television audio, and for special radio music . 3. Single sideband (SSB). In this type of transmission, we work with only one of the

Full-duplex radio over fiber link with colorless source-free base station based on single sideband optical mm-wave signal with polarization rotated optical carrier

NASA Astrophysics Data System (ADS)

Ma, Jianxin

2016-07-01

A full-duplex radio-over fiber (RoF) link scheme based on single sideband (SSB) optical millimeter (mm)-wave signal with polarization-rotated optical carrier is proposed to realize the source-free colorless base station (BS), in which a polarization beam splitter (PBS) is used to abstract part of the optical carrier for conveying the uplink data. Since the optical carrier for the uplink does not bear the downlink signal, no cross-talk from the downlink contaminates the uplink signal. The simulation results demonstrate that both down- and up-links maintain good performance. The mm-wave signal distribution network based on the proposed full duplex fiber link scheme can use the uniform source-free colorless BSs, which makes the access system very simpler.

Receiver sensitivity improvement in spectrally-efficient guard-band twin-SSB-OFDM using an optical IQ modulator

NASA Astrophysics Data System (ADS)

Chen, Ming; Peng, Miao; Zhou, Hui; Zheng, Zhiwei; Tang, Xionggui; Maivan, Lap

2017-12-01

To further improve receiver sensitivity of spectrally-efficient guard-band direct-detection optical orthogonal frequency-division multiplexing (OFDM) with twin single-side-band (SSB) modulation technique, an optical IQ modulator (IQM) is employed to optimize optical carrier-to-signal power ratio (CSPR). The CSPRs for the guard-band twin-SSB-OFDM signal generated by using dual-drive Mach-Zehnder modulator (DD-MZM) and optical IQM are theoretically analyzed and supported by simulations. The optimal CSPR for the two types of guard-band twin-SSB-OFDM are identified. The simulations exhibit that the error vector magnitude (EVM) performance of the IQM-enabled guard-band twin-SSB-OFDM is improved by more than 4-dB compared to that of the twin-SSB-OFDM enabled by DD-MZM after 80-km single-mode fiber (SMF) transmission. In addition, more than 3-dB and 10 dB receiver sensitivity improvements in terms of received optical power (ROP) and optical signal-to-noise ratio (OSNR) are also achieved, respectively.

Advanced satellite communication system

NASA Technical Reports Server (NTRS)

Staples, Edward J.; Lie, Sen

1992-01-01

The objective of this research program was to develop an innovative advanced satellite receiver/demodulator utilizing surface acoustic wave (SAW) chirp transform processor and coherent BPSK demodulation. The algorithm of this SAW chirp Fourier transformer is of the Convolve - Multiply - Convolve (CMC) type, utilizing off-the-shelf reflective array compressor (RAC) chirp filters. This satellite receiver, if fully developed, was intended to be used as an on-board multichannel communications repeater. The Advanced Communications Receiver consists of four units: (1) CMC processor, (2) single sideband modulator, (3) demodulator, and (4) chirp waveform generator and individual channel processors. The input signal is composed of multiple user transmission frequencies operating independently from remotely located ground terminals. This signal is Fourier transformed by the CMC Processor into a unique time slot for each user frequency. The CMC processor is driven by a waveform generator through a single sideband (SSB) modulator. The output of the coherent demodulator is composed of positive and negative pulses, which are the envelopes of the chirp transform processor output. These pulses correspond to the data symbols. Following the demodulator, a logic circuit reconstructs the pulses into data, which are subsequently differentially decoded to form the transmitted data. The coherent demodulation and detection of BPSK signals derived from a CMC chirp transform processor were experimentally demonstrated and bit error rate (BER) testing was performed. To assess the feasibility of such advanced receiver, the results were compared with the theoretical analysis and plotted for an average BER as a function of signal-to-noise ratio. Another goal of this SBIR program was the development of a commercial product. The commercial product developed was an arbitrary waveform generator. The successful sales have begun with the delivery of the first arbitrary waveform generator.

Methods and devices based on brillouin selective sideband amplification

NASA Technical Reports Server (NTRS)

Yao, X. Steve (Inventor)

2003-01-01

Opto-electronic devices and techniques using Brillouin scattering to select a sideband in a modulated optical carrier signal for amplification. Two lasers respectively provide a carrier signal beam and a Brillouin pump beam which are fed into an Brillouin optical medium in opposite directions. The relative frequency separation between the lasers is adjusted to align the frequency of the backscattered Brillouin signal with a desired sideband in the carrier signal to effect a Brillouin gain on the sideband. This effect can be used to implement photonic RF signal mixing and conversion with gain, conversion from phase modulation to amplitude modulation, photonic RF frequency multiplication, optical and RF pulse generation and manipulation, and frequency-locking of lasers.

Accurate optical vector network analyzer based on optical single-sideband modulation and balanced photodetection.

PubMed

Xue, Min; Pan, Shilong; Zhao, Yongjiu

2015-02-15

A novel optical vector network analyzer (OVNA) based on optical single-sideband (OSSB) modulation and balanced photodetection is proposed and experimentally demonstrated, which can eliminate the measurement error induced by the high-order sidebands in the OSSB signal. According to the analytical model of the conventional OSSB-based OVNA, if the optical carrier in the OSSB signal is fully suppressed, the measurement result is exactly the high-order-sideband-induced measurement error. By splitting the OSSB signal after the optical device-under-test (ODUT) into two paths, removing the optical carrier in one path, and then detecting the two signals in the two paths using a balanced photodetector (BPD), high-order-sideband-induced measurement error can be ideally eliminated. As a result, accurate responses of the ODUT can be achieved without complex post-signal processing. A proof-of-concept experiment is carried out. The magnitude and phase responses of a fiber Bragg grating (FBG) measured by the proposed OVNA with different modulation indices are superimposed, showing that the high-order-sideband-induced measurement error is effectively removed.

Low Rate Transmission of Video Signals Using Adaptive Delta Modulation.

DTIC Science & Technology

1983-08-15

903-80-C-0476 / . PERFORMING ORGANIZATION NAME AND ADDRESS 10. PROGRAM ELEMENT. PROJECT, TASK AREA & WORK UNIT NUMBERS Research Foundation of CUNY on...transmitted phase, for the demodulation of the signal. AM is presently being used to transmit multilevel * symbols by vestigial or single sideband...34: Vestigial Sideband -- Duobinary 3600 4-Phase + AM 4800" 4-Phase + AM * Vestigial Sideband 8-PSK 7200 Phase and Amplitude Modulation 9600 Phase anl

Large dynamic range optical vector analyzer based on optical single-sideband modulation and Hilbert transform

NASA Astrophysics Data System (ADS)

Xue, Min; Pan, Shilong; Zhao, Yongjiu

2016-07-01

A large dynamic range optical vector analyzer (OVA) based on optical single-sideband modulation is proposed and demonstrated. By dividing the optical signal after optical device under test into two paths, reversing the phase of one swept sideband using a Hilbert transformer in one path, and detecting the two signals from the two paths with a balanced photodetector, the measurement errors induced by the residual -1st-order sideband and the high-order sidebands can be eliminated and the dynamic range of the measurement is increased. In a proof-of-concept experiment, the stimulated Brillouin scattering and a fiber Bragg grating are measured by OVAs with and without the Hilbert transform and balanced photodetection. Results show that about 40-dB improvement in the measurement dynamic range is realized by the proposed OVA.

Kramers-Kronig receiver operable without digital upsampling.

PubMed

Bo, Tianwai; Kim, Hoon

2018-05-28

The Kramers-Kronig (KK) receiver is capable of retrieving the phase information of optical single-sideband (SSB) signal from the optical intensity when the optical signal satisfies the minimum phase condition. Thus, it is possible to direct-detect the optical SSB signal without suffering from the signal-signal beat interference and linear transmission impairments. However, due to the spectral broadening induced by nonlinear operations in the conventional KK algorithm, it is necessary to employ the digital upsampling at the beginning of the digital signal processing (DSP). The increased number of samples at the DSP would hinder the real-time implementation of this attractive receiver. Hence, we propose a new DSP algorithm for KK receiver operable at 2 samples per symbol. We adopt a couple of mathematical approximations to avoid the use of nonlinear operations such as logarithm and exponential functions. By using the proposed algorithm, we demonstrate the transmission of 112-Gb/s SSB orthogonal frequency-division-multiplexed signal over an 80-km fiber link. The results show that the proposed algorithm operating at 2 samples per symbol exhibits similar performance to the conventional KK one operating at 6 samples per symbol. We also present the error analysis of the proposed algorithm for KK receiver in comparison with the conventional one.

Multi-Frequency Signal Detection Based on Frequency Exchange and Re-Scaling Stochastic Resonance and Its Application to Weak Fault Diagnosis.

PubMed

Liu, Jinjun; Leng, Yonggang; Lai, Zhihui; Fan, Shengbo

2018-04-25

Mechanical fault diagnosis usually requires not only identification of the fault characteristic frequency, but also detection of its second and/or higher harmonics. However, it is difficult to detect a multi-frequency fault signal through the existing Stochastic Resonance (SR) methods, because the characteristic frequency of the fault signal as well as its second and higher harmonics frequencies tend to be large parameters. To solve the problem, this paper proposes a multi-frequency signal detection method based on Frequency Exchange and Re-scaling Stochastic Resonance (FERSR). In the method, frequency exchange is implemented using filtering technique and Single SideBand (SSB) modulation. This new method can overcome the limitation of "sampling ratio" which is the ratio of the sampling frequency to the frequency of target signal. It also ensures that the multi-frequency target signals can be processed to meet the small-parameter conditions. Simulation results demonstrate that the method shows good performance for detecting a multi-frequency signal with low sampling ratio. Two practical cases are employed to further validate the effectiveness and applicability of this method.

Theory of low-power ultra-broadband terahertz sideband generation in bi-layer graphene.

PubMed

Crosse, J A; Xu, Xiaodong; Sherwin, Mark S; Liu, R B

2014-09-24

In a semiconductor illuminated by a strong terahertz (THz) field, optically excited electron-hole pairs can recombine to emit light in a broad frequency comb evenly spaced by twice the THz frequency. Such high-order THz sideband generation is of interest both as an example of extreme nonlinear optics and also as a method for ultrafast electro-optical modulation. So far, this phenomenon has only been observed with large field strengths (~10 kV cm(-1)), an obstacle for technological applications. Here we predict that bi-layer graphene generates high-order sidebands at much weaker THz fields. We find that a THz field of strength 1 kV cm(-1) can produce a high-sideband spectrum of about 30 THz, 100 times broader than in GaAs. The sidebands are generated despite the absence of classical collisions, with the quantum coherence of the electron-hole pairs enabling recombination. These remarkable features lower the barrier to desktop electro-optical modulation at THz frequencies, facilitating ultrafast optical communications.

Side-band mutual interactions in the magnetosphere

NASA Technical Reports Server (NTRS)

Chang, D. C. D.; Helliwell, R. A.; Bell, T. F.

1980-01-01

Sideband mutual interactions between VLF waves in the magnetosphere are investigated. Results of an experimental program involving the generation of sidebands by means of frequency shift keying are presented which indicate that the energetic electrons in the magnetosphere can interact only with sidebands generated by signals with short modulation periods. Using the value of the memory time during which electrons interact with the waves implied by the above result, it is estimated that the length of the electron interaction region in the magnetosphere is between 4000 and 2000 km. Sideband interactions are found to be similar to those between constant-frequency signals, exhibiting suppression and energy coupling. Results from a second sideband transmitting program show that for most cases the coherence bandwidth of sidebands is about 50 Hz. Sideband mutual interactions are then explained by the overlap of the ranges of the parallel velocity of the electrons which the sidebands organize, and the wave intensity in the interaction region is estimated to be 2.5-10 milli-gamma, in agreement with satellite measurements.

Advanced Technology Direction and Control Communications Systems

DTIC Science & Technology

1979-07-16

Leupert amesD./Morrell ~I~ Frederick . euprJae DCPAaol-78-C-1 259] ,. IERFORMlk6 ORGANIZATION NAME AND ADDRESS %a. P ROGRAM ELEMiENT. PROJIECT. TASK AREA...without the change in communicatios LCciniLlucs b•;i,,g aipiarci-IL. A JTIDS net is organized on the principle of time division. Various elements are...sideband (DSB-AI) "* Amplitude modulation, vestigial sideband (VSB-AM) * Frequency sI Shift modulation (FSK) "* Phase shift modulation (PSK) Ti DSB

BPSK optical mm-wave signal generation by septupling frequency via a single optical phase modulator

NASA Astrophysics Data System (ADS)

Wu, Peng; Ma, Jianxin

2016-09-01

In this paper, we have proposed a novel and simple scheme to generate the BPSK optical millimeter wave (MMW) signal with frequency septupling by using an optical phase modulator (PM) and a wavelength selective switch (WSS). In this scheme, the PM is driven by a radio frequency (RF) BPSK signal at the optimized modulation index of 4.89 to assure the 4th and 3rd-order sidebands have equal amplitudes. An wavelength selective switch (WSS) is used to abstract the -4th and +3rd-order sidebands from the spectrum generated by RF BPSK signal modulating the lightwave to form the BPSK optical MMW signal with frequency septupling the driving RF signal. In these two tones, only the +3rd-order sideband bears the BPSK signal while the -4th-order sideband is unmodulated since the phase information is canceled by the even times multiplication of the phase of BPSK signal. The MMW signal can avoid the pulse walk-off effect and the amplitude fading effect caused by the fiber chromatic dispersion. By adjusting the modulation index to assure the two tones have equal amplitude, the generated optical MMW signal has the maximal opto-electrical conversion efficiency and good transmission performance.

Chirped laser dispersion spectroscopy using a directly modulated quantum cascade laser

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

Hangauer, Andreas, E-mail: hangauer@princeton.edu; Nikodem, Michal; Wysocki, Gerard, E-mail: gwysocki@princeton.edu

2013-11-04

Chirped laser dispersion spectroscopy (CLaDS) utilizing direct modulation of a quantum cascade laser (QCL) is presented. By controlling the laser bias nearly single- and dual-sideband CLaDS operation can be realized in an extremely simplified optical setup with no external optical modulators. Capability of direct single-sideband modulation is a unique feature of QCLs that exhibit a low linewidth enhancement factor. The developed analytical model shows excellent agreement with the experimental, directly modulated CLaDS spectra. This method overcomes major technical limitations of mid-infrared CLaDS systems by allowing significantly higher modulation frequencies and eliminating optical fringes introduced by external modulators.

Generation of optical OFDM signals using 21.4 GS/s real time digital signal processing.

PubMed

Benlachtar, Yannis; Watts, Philip M; Bouziane, Rachid; Milder, Peter; Rangaraj, Deepak; Cartolano, Anthony; Koutsoyannis, Robert; Hoe, James C; Püschel, Markus; Glick, Madeleine; Killey, Robert I

2009-09-28

We demonstrate a field programmable gate array (FPGA) based optical orthogonal frequency division multiplexing (OFDM) transmitter implementing real time digital signal processing at a sample rate of 21.4 GS/s. The QPSK-OFDM signal is generated using an 8 bit, 128 point inverse fast Fourier transform (IFFT) core, performing one transform per clock cycle at a clock speed of 167.2 MHz and can be deployed with either a direct-detection or a coherent receiver. The hardware design and the main digital signal processing functions are described, and we show that the main performance limitation is due to the low (4-bit) resolution of the digital-to-analog converter (DAC) and the 8-bit resolution of the IFFT core used. We analyze the back-to-back performance of the transmitter generating an 8.36 Gb/s optical single sideband (SSB) OFDM signal using digital up-conversion, suitable for direct-detection. Additionally, we use the device to transmit 8.36 Gb/s SSB OFDM signals over 200 km of uncompensated standard single mode fiber achieving an overall BER<10(-3).

Modulation of intracellular protein degradation by SSB1-SIS1 chaperon system in yeast S. cerevisiae.

PubMed

Ohba, M

1997-06-09

In prokaryotes, DnaK-DnaJ chaperon is involved in the protein degradation catalyzed by proteases La and ClpA/B complex as shown in E. coli. To extend this into eukaryotic cells, we examined the effects of hsp70 genes, SSA1 and SSB1, and DnaJ genes, SIS1 and YDJ1, on the growth of proteasome subunit mutants of the yeast S. cerevisiae. The results identified SSB1 and SIS1 as a pair of chaperon genes specifically involved in efficient protein turnover in the yeast, whose overexpression suppressed the growth defects caused by the proteasome mutations. Moreover, a single amino acid substitution in the putative peptide-binding site of SSB1 protein profoundly enhanced the suppression activity, indicating that the activity is mediated by the peptide-binding activity of this chaperon. Thus SSB1, with its partner DnaJ, SIS1, modulates the efficiency of protein turnover through its chaperon activity.

An ultrawide-bandwidth single-sideband modulator for terahertz frequencies

NASA Astrophysics Data System (ADS)

Meijer, A. S.; Berden, G.; Arslanov, D. D.; Ozerov, M.; Jongma, R. T.; van der Zande, W. J.

2016-11-01

Wireless high-speed data communication using terahertz (THz) carrier frequencies is becoming reality with data rates beyond 100 Gbit s-1. Many of the mobile applications use internet access and require that THz wireless base stations are connected to a global network, such as the radio-over-fibre network. We present the realization of an ultrawide bandwidth THz optical single-sideband (OSSB) modulator for converting (free-space) THz signals to THz optical modulations with an increased spectral efficiency. THz OSSB will mitigate chromatic dispersion-induced propagation losses in optical fibres and support digital modulation schemes. We demonstrate THz OSSB for free-space radiation between 0.3 and 1.0 THz using a specially designed dichroic beamsplitter for signal and carrier, and a planar light-wave circuit with multimode interference structures. This arrangement of optical elements mimics the Hartley single-sideband modulator for electronics signals and accomplishes the required Hilbert transform without any frequency-dependent tuning element over an ultrawide THz spectrum.

Periodically modulated single-photon transport in one-dimensional waveguide

NASA Astrophysics Data System (ADS)

Li, Xingmin; Wei, L. F.

2018-03-01

Single-photon transport along a one-dimension waveguide interacting with a quantum system (e.g., two-level atom) is a very useful and meaningful simplified model of the waveguide-based optical quantum devices. Thus, how to modulate the transport of the photons in the waveguide structures by adjusting certain external parameters should be particularly important. In this paper, we discuss how such a modulation could be implemented by periodically driving the energy splitting of the interacting atom and the atom-photon coupling strength. By generalizing the well developed time-independent full quantum mechanical theory in real space to the time-dependent one, we show that various sideband-transmission phenomena could be observed. This means that, with these modulations the photon has certain probabilities to transmit through the scattering atom in the other energy sidebands. Inversely, by controlling the sideband transmission the periodic modulations of the single photon waveguide devices could be designed for the future optical quantum information processing applications.

Frequency-Offset Cartesian Feedback Based on Polyphase Difference Amplifiers

PubMed Central

Zanchi, Marta G.; Pauly, John M.; Scott, Greig C.

2010-01-01

A modified Cartesian feedback method called “frequency-offset Cartesian feedback” and based on polyphase difference amplifiers is described that significantly reduces the problems associated with quadrature errors and DC-offsets in classic Cartesian feedback power amplifier control systems. In this method, the reference input and feedback signals are down-converted and compared at a low intermediate frequency (IF) instead of at DC. The polyphase difference amplifiers create a complex control bandwidth centered at this low IF, which is typically offset from DC by 200–1500 kHz. Consequently, the loop gain peak does not overlap DC where voltage offsets, drift, and local oscillator leakage create errors. Moreover, quadrature mismatch errors are significantly attenuated in the control bandwidth. Since the polyphase amplifiers selectively amplify the complex signals characterized by a +90° phase relationship representing positive frequency signals, the control system operates somewhat like single sideband (SSB) modulation. However, the approach still allows the same modulation bandwidth control as classic Cartesian feedback. In this paper, the behavior of the polyphase difference amplifier is described through both the results of simulations, based on a theoretical analysis of their architecture, and experiments. We then describe our first printed circuit board prototype of a frequency-offset Cartesian feedback transmitter and its performance in open and closed loop configuration. This approach should be especially useful in magnetic resonance imaging transmit array systems. PMID:20814450

Nonlinear ultrasonic wave modulation for online fatigue crack detection

NASA Astrophysics Data System (ADS)

Sohn, Hoon; Lim, Hyung Jin; DeSimio, Martin P.; Brown, Kevin; Derriso, Mark

2014-02-01

This study presents a fatigue crack detection technique using nonlinear ultrasonic wave modulation. Ultrasonic waves at two distinctive driving frequencies are generated and corresponding ultrasonic responses are measured using permanently installed lead zirconate titanate (PZT) transducers with a potential for continuous monitoring. Here, the input signal at the lower driving frequency is often referred to as a 'pumping' signal, and the higher frequency input is referred to as a 'probing' signal. The presence of a system nonlinearity, such as a crack formation, can provide a mechanism for nonlinear wave modulation, and create spectral sidebands around the frequency of the probing signal. A signal processing technique combining linear response subtraction (LRS) and synchronous demodulation (SD) is developed specifically to extract the crack-induced spectral sidebands. The proposed crack detection method is successfully applied to identify actual fatigue cracks grown in metallic plate and complex fitting-lug specimens. Finally, the effect of pumping and probing frequencies on the amplitude of the first spectral sideband is investigated using the first sideband spectrogram (FSS) obtained by sweeping both pumping and probing signals over specified frequency ranges.

Dynamic single sideband modulation for realizing parametric loudspeaker

NASA Astrophysics Data System (ADS)

Sakai, Shinichi; Kamakura, Tomoo

2008-06-01

A parametric loudspeaker, that presents remarkably narrow directivity compared with a conventional loudspeaker, is newly produced and examined. To work the loudspeaker optimally, we prototyped digitally a single sideband modulator based on the Weaver method and appropriate signal processing. The processing techniques are to change the carrier amplitude dynamically depending on the envelope of audio signals, and then to operate the square root or fourth root to the carrier amplitude for improving input-output acoustic linearity. The usefulness of the present modulation scheme has been verified experimentally.

Vibrational molecular modulation in hydrogen

NASA Astrophysics Data System (ADS)

Huang, Shu Wei; Chen, Wei-Jan; Kung, A. H.

2006-12-01

Detailed numerical modeling of using the vibrational coherence of H2 for molecular modulation is presented. The focus of the calculation is on a strongly driven system aimed at producing many sidebands in the presence of Doppler broadening and the effects of collisions at room temperature. It is shown that Dicke narrowing that reduces the Doppler width plays a critical role in high order sideband generation in room temperature H2 . In addition, the calculation shows that generation of many sidebands favors the phased state as has been reported in all gas phase experiments and is primarily a consequence of the Stark shifts that result from the applied high intensities. The influence of self-focusing in the gas medium that has been conjectured in previous studies is only secondary. The numerical results agree with experimental data obtained in our laboratory, where we have succeeded in generating collinearly propagating Raman sidebands with wavelengths that range from 2216nm in the infrared to 133nm in the vacuum ultraviolet. The frequencies covered by these sidebands span over four octaves for a total of more than 70600cm-1 in the optical region of the spectrum.

Theory of low-power ultra-broadband terahertz sideband generation in bi-layer graphene

PubMed Central

Crosse, J. A.; Xu, Xiaodong; Sherwin, Mark S.; Liu, R. B.

2014-01-01

In a semiconductor illuminated by a strong terahertz (THz) field, optically excited electron–hole pairs can recombine to emit light in a broad frequency comb evenly spaced by twice the THz frequency. Such high-order THz sideband generation is of interest both as an example of extreme nonlinear optics and also as a method for ultrafast electro-optical modulation. So far, this phenomenon has only been observed with large field strengths (~10 kV cm−1), an obstacle for technological applications. Here we predict that bi-layer graphene generates high-order sidebands at much weaker THz fields. We find that a THz field of strength 1 kV cm−1 can produce a high-sideband spectrum of about 30 THz, 100 times broader than in GaAs. The sidebands are generated despite the absence of classical collisions, with the quantum coherence of the electron–hole pairs enabling recombination. These remarkable features lower the barrier to desktop electro-optical modulation at THz frequencies, facilitating ultrafast optical communications. PMID:25249245

Filterless frequency-octupling mm-wave generation by cascading Sagnac loop and DPMZM

NASA Astrophysics Data System (ADS)

Zhang, Wu; Wen, Aijun; Gao, Yongsheng; Shang, Shuo; Zheng, Hanxiao; He, Hongye

2017-12-01

In this paper, a filterless photonic frequency-octupling scheme is presented. It is implemented by cascading a Sagnac loop with an intensity modulator (IM) in it and a dual-parallel Mach-Zehnder modulator (DPMZM) in series. The Sagnac loop is used to get the ±2nd-order sidebands of LO signal. The following DPMZM is utilized to obtain the ±4th-order sidebands. By photo-detecting the ±4th-order sidebands, mm-wave signal with the eightfold frequency of LO signal can be obtained. The scheme is verified by experiments, and a 32-GHz mm-wave signal is produced with the assistance of a 4-GHz LO signal. A 20-dB optical sideband suppression ratio (OSSR) and a 17-dB electrical spurious suppression ratio (ESSR) are realized, and no extra deterioration of phase noise is observed. Besides, the verification of the frequency tunability is implemented in the experiment.

Optical single sideband millimeter-wave signal generation and transmission using 120° hybrid coupler

NASA Astrophysics Data System (ADS)

Zheng, Zhiwei; Peng, Miao; Zhou, Hui; Chen, Ming; Jiang, Leyong; Tan, Li; Dai, Xiaoyu; Xiang, Yuanjiang

2018-03-01

We propose a novel 60 GHz optical single sideband (OSSB) millimeter-wave (mm-wave) signal generation scheme using 120° hybrid coupler based on external integrated Mach-Zehnder modulator (MZM). The proposed scheme shows that the bit error ratio (BER) performance is improved by suppressing the +2nd-order sideband. Meanwhile, the transmission distance is extended as only the optical +1st-order sideband is modulated by using 5 Gbit/s baseband signal while the carrier is blank, owing to the elimination of walk-off effect suffered from fiber dispersion. The simulation results demonstrated that the eye diagrams of the generated 60 GHz OSSB signal keep open and clear after 100 km standard single-mode fiber (SSMF). In addition, the proposed scheme can achieve 2 dB receiver sensitivity improvements than the conventional 90° hybrid coupler when transmitted over 100 km SSMF at a BER of 10-9.

Multi-Frequency Signal Detection Based on Frequency Exchange and Re-Scaling Stochastic Resonance and Its Application to Weak Fault Diagnosis

PubMed Central

Leng, Yonggang; Fan, Shengbo

2018-01-01

Mechanical fault diagnosis usually requires not only identification of the fault characteristic frequency, but also detection of its second and/or higher harmonics. However, it is difficult to detect a multi-frequency fault signal through the existing Stochastic Resonance (SR) methods, because the characteristic frequency of the fault signal as well as its second and higher harmonics frequencies tend to be large parameters. To solve the problem, this paper proposes a multi-frequency signal detection method based on Frequency Exchange and Re-scaling Stochastic Resonance (FERSR). In the method, frequency exchange is implemented using filtering technique and Single SideBand (SSB) modulation. This new method can overcome the limitation of "sampling ratio" which is the ratio of the sampling frequency to the frequency of target signal. It also ensures that the multi-frequency target signals can be processed to meet the small-parameter conditions. Simulation results demonstrate that the method shows good performance for detecting a multi-frequency signal with low sampling ratio. Two practical cases are employed to further validate the effectiveness and applicability of this method. PMID:29693577

140 GHz pulsed Fourier transform microwave spectrometer

DOEpatents

Kolbe, W.F.; Leskovar, B.

1985-07-29

A high frequency energy pulsing system suitable for use in a pulsed microwave spectrometer, including means for generating a high frequency carrier signal, and means for generating a low frequency modulating signal. The carrier signal is continuously fed to a modulator and the modulating signal is fed through a pulse switch to the modulator. When the pulse switch is on, the modulator will produce sideband signals above and below the carrier signal frequency. A frequency-responsive device is tuned to one of the sideband signals and sway from the carrier frequency so that the high frequency energization of the frequency-responsive device is controlled by the pulse switch.

140 GHz pulsed Fourier transform microwave spectrometer

DOEpatents

Kolbe, W.F.; Leskovar, B.

1987-10-27

A high frequency energy pulsing system suitable for use in a pulsed microwave spectrometer, including means for generating a high frequency carrier signal, and means for generating a low frequency modulating signal is disclosed. The carrier signal is continuously fed to a modulator and the modulating signal is fed through a pulse switch to the modulator. When the pulse switch is on, the modulator will produce sideband signals above and below the carrier signal frequency. A frequency-responsive device is tuned to one of the sideband signals and away from the carrier frequency so that the high frequency energization of the frequency-responsive device is controlled by the pulse switch. 5 figs.

Simultaneous transmission of wired and wireless signals based on double sideband carrier suppression

NASA Astrophysics Data System (ADS)

Bitew, Mekuanint Agegnehu; Shiu, Run-Kai; Peng, Peng-Chun; Wang, Cheng-Hao; Chen, Yan-Ming

2017-11-01

In this paper, we proposed and experimentally demonstrated simultaneous transmission of wired and wireless signals based on double sideband optical carrier suppression. By properly adjusting the bias point of the dual-output mach-zehnder modulator (MZM), a central carrier in one output port and a pair of first-order sidebands in another output port are generated. The pair of first-order sidebands are fed into a second MZM to generate second-order order sidebands. A wired signal is embedded on the central carrier while a wireless signal is embedded on the second-order sidebands. Unlike other schemes, we did not use optical filter to separate the carrier from the optical sidebands. The measured bit error rate (BER) and eye-diagrams after a 25 km single-mode-fiber (SMF) transmission proved that the proposed scheme is successful for both wired and wireless signals transmission. Moreover, the power penalty at the BER of 10-9 is 0.3 and 0.7 dB for wired and wireless signals, respectively.

Alternative laser system for cesium magneto-optical trap via optical injection locking to sideband of a 9-GHz current-modulated diode laser.

PubMed

Diao, Wenting; He, Jun; Liu, Zhi; Yang, Baodong; Wang, Junmin

2012-03-26

By optical injection of an 852-nm extended-cavity diode laser (master laser) to lock the + 1-order sideband of a ~9-GHz-current-modulated diode laser (slave laser), we generate a pair of phase-locked lasers with a frequency difference up to ~9-GHz for a cesium (Cs) magneto-optical trap (MOT) with convenient tuning capability. For a cesium MOT, the master laser acts as repumping laser, locked to the Cs 6S₁/₂ (F = 3) - 6P₃/₂ (F' = 4) transition. When the + 1-order sideband of the 8.9536-GHz-current-modulated slave laser is optically injection-locked, the carrier operates on the Cs 6S₁/₂ (F = 4) - 6P₃/₂ (F' = 5) cooling cycle transition with -12 MHz detuning and acts as cooling/trapping laser. When carrying a 9.1926-GHz modulation signal, this phase-locked laser system can be applied in the fields of coherent population trapping and coherent manipulation of Cs atomic ground states.

Tunable microwave photonic filter free from baseband and carrier suppression effect not requiring single sideband modulation using a Mach-Zenhder configuration.

PubMed

Mora, José; Ortigosa-Blanch, Arturo; Pastor, Daniel; Capmany, José

2006-08-21

We present a full theoretical and experimental analysis of a novel all-optical microwave photonic filter combining a mode-locked fiber laser and a Mach-Zenhder structure in cascade to a 2x1 electro-optic modulator. The filter is free from the carrier suppression effect and thus it does not require single sideband modulation. Positive and negative coefficients are obtained inherently in the system and the tunability is achieved by controlling the optical path difference of the Mach-Zenhder structure.

Electrooptic modulation methods for high sensitivity tunable diode laser spectroscopy

NASA Technical Reports Server (NTRS)

Glenar, David A.; Jennings, Donald E.; Nadler, Shacher

1990-01-01

A CdTe phase modulator and low power RF sources have been used with Pb-salt tunable diode lasers operating near 8 microns to generate optical sidebands for high sensitivity absorption spectroscopy. Sweep averaged, first-derivative sample spectra of CH4 were acquired by wideband phase sensitive detection of the electrooptically (EO) generated carrier-sideband beat signal. EO generated beat signals were also used to frequency lock the TDL to spectral lines. This eliminates low frequency diode jitter, and avoids the excess laser linewidth broadening that accompanies TDL current modulation frequency locking methods.

The human mitochondrial single-stranded DNA-binding protein displays distinct kinetics and thermodynamics of DNA binding and exchange

PubMed Central

Qian, Yufeng; Johnson, Kenneth A.

2017-01-01

The human mitochondrial ssDNA-binding protein (mtSSB) is a homotetrameric protein, involved in mtDNA replication and maintenance. Although mtSSB is structurally similar to SSB from Escherichia coli (EcoSSB), it lacks the C-terminal disordered domain, and little is known about the biophysics of mtSSB–ssDNA interactions. Here, we characterized the kinetics and thermodynamics of mtSSB binding to ssDNA by equilibrium titrations and stopped-flow kinetic measurements. We show that the mtSSB tetramer can bind to ssDNA in two distinct binding modes: (SSB)30 and (SSB)60, defined by DNA binding site sizes of 30 and 60 nucleotides, respectively. We found that the binding mode is modulated by magnesium ion and NaCl concentration, but unlike EcoSSB, the mtSSB does not show negative intersubunit cooperativity. Global fitting of both the equilibrium and kinetic data afforded estimates for the rate and equilibrium constants governing the formation of (SSB)60 and (SSB)30 complexes and for the transitions between the two binding modes. We found that the mtSSB tetramer binds to ssDNA with a rate constant near the diffusion limit (2 × 109 m−1 s−1) and that longer DNA (≥60 nucleotides) rapidly wraps around all four monomers, as revealed by FRET assays. We also show that the mtSSB tetramer can directly transfer from one ssDNA molecule to another via an intermediate with two DNA molecules bound to the mtSSB. In conclusion, our results indicate that human mtSSB shares many physicochemical properties with EcoSSB and that the differences may be explained by the lack of an acidic, disordered C-terminal tail in human mtSSB protein. PMID:28615444

Multi-tap complex-coefficient incoherent microwave photonic filters based on optical single-sideband modulation and narrow band optical filtering.

PubMed

Sagues, Mikel; García Olcina, Raimundo; Loayssa, Alayn; Sales, Salvador; Capmany, José

2008-01-07

We propose a novel scheme to implement tunable multi-tap complex coefficient filters based on optical single sideband modulation and narrow band optical filtering. A four tap filter is experimentally demonstrated to highlight the enhanced tuning performance provided by complex coefficients. Optical processing is performed by the use of a cascade of four phase-shifted fiber Bragg gratings specifically fabricated for this purpose.

Reference-free fatigue crack detection using nonlinear ultrasonic modulation under various temperature and loading conditions

NASA Astrophysics Data System (ADS)

Lim, Hyung Jin; Sohn, Hoon; DeSimio, Martin P.; Brown, Kevin

2014-04-01

This study presents a reference-free fatigue crack detection technique using nonlinear ultrasonic modulation. When low frequency (LF) and high frequency (HF) inputs generated by two surface-mounted lead zirconate titanate (PZT) transducers are applied to a structure, the presence of a fatigue crack can provide a mechanism for nonlinear ultrasonic modulation and create spectral sidebands around the frequency of the HF signal. The crack-induced spectral sidebands are isolated using a combination of linear response subtraction (LRS), synchronous demodulation (SD) and continuous wavelet transform (CWT) filtering. Then, a sequential outlier analysis is performed on the extracted sidebands to identify the crack presence without referring any baseline data obtained from the intact condition of the structure. Finally, the robustness of the proposed technique is demonstrated using actual test data obtained from simple aluminum plate and complex aircraft fitting-lug specimens under varying temperature and loading variations.

High-speed tunable microwave photonic notch filter based on phase modulator incorporated Lyot filter.

PubMed

Ge, Jia; Feng, Hanlin; Scott, Guy; Fok, Mable P

2015-01-01

A high-speed tunable microwave photonic notch filter with ultrahigh rejection ratio is presented, which is achieved by semiconductor optical amplifier (SOA)-based single-sideband modulation and optical spectral filtering with a phase modulator-incorporated Lyot (PM-Lyot) filter. By varying the birefringence of the phase modulator through electro-optic effect, electrically tuning of the microwave photonic notch filter is experimentally achieved at tens of gigahertz speed. The use of SOA-polarizer based single-sideband modulation scheme provides good sideband suppression over a wide frequency range, resulting in an ultrahigh rejection ratio of the microwave photonic notch filter. Stable filter spectrum with bandstop rejection ratio over 60 dB is observed over a frequency tuning range from 1.8 to 10 GHz. Compare with standard interferometric notch filter, narrower bandwidth and sharper notch profile are achieved with the unique PM-Lyot filter, resulting in better filter selectivity. Moreover, bandwidth tuning is also achieved through polarization adjustment inside the PM-Lyot filter, that the 10-dB filter bandwidth is tuned from 0.81 to 1.85 GHz.

High-accurate optical vector analysis based on optical single-sideband modulation

NASA Astrophysics Data System (ADS)

Xue, Min; Pan, Shilong

2016-11-01

Most of the efforts devoted to the area of optical communications were on the improvement of the optical spectral efficiency. Varies innovative optical devices are thus developed to finely manipulate the optical spectrum. Knowing the spectral responses of these devices, including the magnitude, phase and polarization responses, is of great importance for their fabrication and application. To achieve high-resolution characterization, optical vector analyzers (OVAs) based on optical single-sideband (OSSB) modulation have been proposed and developed. Benefiting from the mature and highresolution microwave technologies, the OSSB-based OVA can potentially achieve a resolution of sub-Hz. However, the accuracy is restricted by the measurement errors induced by the unwanted first-order sideband and the high-order sidebands in the OSSB signal, since electrical-to-optical conversion and optical-to-electrical conversion are essentially required to achieve high-resolution frequency sweeping and extract the magnitude and phase information in the electrical domain. Recently, great efforts have been devoted to improve the accuracy of the OSSB-based OVA. In this paper, the influence of the unwanted-sideband induced measurement errors and techniques for implementing high-accurate OSSB-based OVAs are discussed.

140 GHz pulsed fourier transform microwave spectrometer

DOEpatents

Kolbe, William F.; Leskovar, Branko

1987-01-01

A high frequency energy pulsing system suitable for use in a pulsed microwave spectrometer (10), including means (11, 19) for generating a high frequency carrier signal, and means (12) for generating a low frequency modulating signal. The carrier signal is continuously fed to a modulator (20) and the modulating signal is fed through a pulse switch (23) to the modulator. When the pulse switch (23) is on, the modulator (20) will produce sideband signals above and below the carrier signal frequency. A frequency-responsive device (31) is tuned to one of the sideband signals and away from the carrier frequency so that the high frequency energization of the frequency-responsive device (31) is controlled by the pulse switch (23).

High Precision Laser Range Sensor

NASA Technical Reports Server (NTRS)

Dubovitsky, Serge (Inventor); Lay, Oliver P. (Inventor)

2003-01-01

The present invention is an improved distance measuring interferometer that includes high speed phase modulators and additional phase meters to generate and analyze multiple heterodyne signal pairs with distinct frequencies. Modulation sidebands with large frequency separation are generated by the high speed electro-optic phase modulators, requiring only a single frequency stable laser source and eliminating the need for a fist laser to be tuned or stabilized relative to a second laser. The combination of signals produced by the modulated sidebands is separated and processed to give the target distance. The resulting metrology apparatus enables a sensor with submicron accuracy or better over a multi- kilometer ambiguity range.

Single-sideband modulator for frequency domain multiplexing of superconducting qubit readout

NASA Astrophysics Data System (ADS)

Chapman, Benjamin J.; Rosenthal, Eric I.; Kerckhoff, Joseph; Vale, Leila R.; Hilton, Gene C.; Lehnert, K. W.

2017-04-01

We introduce and experimentally characterize a superconducting single-sideband modulator compatible with cryogenic microwave circuits and propose its use for frequency domain multiplexing of superconducting qubit readout. The monolithic double-balanced modulators that comprise the device are formed with purely reactive elements (capacitors and Josephson junction inductors) and require no microwave-frequency control tones. Microwave signals in the 4 to 8 GHz band, with power up to -85 dBm, are converted up or down in frequency by as much as 120 MHz. Spurious harmonics in the device can be suppressed by up to 25 dB for select probe and modulation frequencies.

Inspection system calibration methods

DOEpatents

Deason, Vance A.; Telschow, Kenneth L.

2004-12-28

An inspection system calibration method includes producing two sideband signals of a first wavefront; interfering the two sideband signals in a photorefractive material, producing an output signal therefrom having a frequency and a magnitude; and producing a phase modulated operational signal having a frequency different from the output signal frequency, a magnitude, and a phase modulation amplitude. The method includes determining a ratio of the operational signal magnitude to the output signal magnitude, determining a ratio of a 1st order Bessel function of the operational signal phase modulation amplitude to a 0th order Bessel function of the operational signal phase modulation amplitude, and comparing the magnitude ratio to the Bessel function ratio.

New kind of injection-locked oscillator and its corresponding long-term stability control.

PubMed

Hong, Jun; Liu, An; Wang, Xiao-hu; Yao, Sheng-xing; Li, Zu-ling

2015-09-20

A new type of opto-electronic hybrid oscillator is proposed for the first time, to the best of our knowledge, and verified by experiments in this paper. Typical electronic oscillator-dielectric resonator oscillator as the first injection source is used to injection lock the first long-fiber loop-based opto-electronic oscillator (OEO); then its output is used to injection lock the second long-fiber opto-electronic oscillator. Using this method, low-phase noise output signal can be obtained. Experiments show that single side-band (SSB) phase noise of a 9.5 GHz oscillation signal at 10 kHz offset frequency decreases from -123 to -135  dBc/Hz after the first injection, then, through the second injection, the SSB phase noise drops down to -146  dBc/Hz. In order to solve the long-term stability problem of the above oscillator, a new stability-control circuit also is designed and verified by experiments. Experiments show that the Allan deviation decreases from 9.0×10(-11) to 2.2×10(-12) during 1 s after the long-term stability-control circuit being used.

Optical vector network analyzer with improved accuracy based on polarization modulation and polarization pulling.

PubMed

Li, Wei; Liu, Jian Guo; Zhu, Ning Hua

2015-04-15

We report a novel optical vector network analyzer (OVNA) with improved accuracy based on polarization modulation and stimulated Brillouin scattering (SBS) assisted polarization pulling. The beating between adjacent higher-order optical sidebands which are generated because of the nonlinearity of an electro-optic modulator (EOM) introduces considerable error to the OVNA. In our scheme, the measurement error is significantly reduced by removing the even-order optical sidebands using polarization discrimination. The proposed approach is theoretically analyzed and experimentally verified. The experimental results show that the accuracy of the OVNA is greatly improved compared to a conventional OVNA.

A novel approach to photonic generate microwave signals based on optical injection locking and four-wave mixing

NASA Astrophysics Data System (ADS)

Zhu, Huatao; Wang, Rong; Xiang, Peng; Pu, Tao; Fang, Tao; Zheng, Jilin; Li, Yuandong

2017-10-01

In this paper, a novel approach for photonic generation of microwave signals based on frequency multiplication using an injected distributed-feedback (DFB) semiconductor laser is proposed and demonstrated by a proof-of-concept experiment. The proposed system is mainly made up of a dual-parallel Mach-Zehnder modulator (DPMZM) and an injected DFB laser. By properly setting the bias voltage of the DPMZM, ±2-order sidebands with carrier suppression are generated, which are then injected into the slave laser. Due to the optical sideband locking and four-wave mixing (FWM) nonlinearity in the slave laser, new sidebands are generated. Then these sidebands are sent to an optical notch filter where all the undesired sidebands are removed. Finally, after photodetector detection, frequency multiplied microwave signals can be generated. Thanks to the flexibility of the optical sideband locking and FWM, frequency octupling, 12-tupling, 14-tupling and 16-tupling can be obtained.

Frequency modulation spectroscopy with a THz quantum-cascade laser.

PubMed

Eichholz, R; Richter, H; Wienold, M; Schrottke, L; Hey, R; Grahn, H T; Hübers, H-W

2013-12-30

We report on a terahertz spectrometer for high-resolution molecular spectroscopy based on a quantum-cascade laser. High-frequency modulation (up to 50 MHz) of the laser driving current produces a simultaneous modulation of the frequency and amplitude of the laser output. The modulation generates sidebands, which are symmetrically positioned with respect to the laser carrier frequency. The molecular transition is probed by scanning the sidebands across it. In this way, the absorption and the dispersion caused by the molecular transition are measured. The signals are modeled by taking into account the simultaneous modulation of the frequency and amplitude of the laser emission. This allows for the determination of the strength of the frequency as well as amplitude modulation of the laser and of molecular parameters such as pressure broadening.

Microbunching-instability-induced sidebands in a seeded free-electron laser

DOE PAGES

Zhang, Zhen; Lindberg, Ryan; Fawley, William M.; ...

2016-05-02

Measurements of the multishot-averaged, soft x-ray, self-seeding spectrum at the LCLS free-electron laser often have a pedestal-like distribution around the seeded wavelength, which limits the spectral purity and can negatively affect some user applications not employing a post-undulator monochromator. In this paper, we study the origins of such pedestals, focusing on longitudinal phase space modulations produced by the microbunching instability upstream of the free-electron laser (FEL) undulator. Furthermore, we show from theory and numerical simulation that both energy and density modulations can induce sidebands in a high-gain, seeded FEL whose fractional strength typically grows as the square of the undulatormore » length. The results place a tight constraint on the longitudinal phase space uniformity of the electron beam for a seeded FEL, possibly requiring the amplitude of long-wavelength modulations to be much smaller than the typical incoherent energy spread if the output sideband power is to remain only a couple percent or less of the amplified seed power.« less

Conversion from non-orthogonally to orthogonally polarized optical single-sideband modulation using optically injected semiconductor lasers.

PubMed

Hung, Yu-Han; Tseng, Chin-Hao; Hwang, Sheng-Kwang

2018-06-01

This Letter investigates an optically injected semiconductor laser for conversion from non-orthogonally to orthogonally polarized optical single-sideband modulation. The underlying mechanism relies solely on nonlinear laser characteristics and, thus, only a typical semiconductor laser is required as the key conversion unit. This conversion can be achieved for a broadly tunable frequency range up to at least 65 GHz. After conversion, the microwave phase quality, including linewidth and phase noise, is mostly preserved, and simultaneous microwave amplification up to 23 dB is feasible.

Advanced infrared laser modulator development

NASA Technical Reports Server (NTRS)

Cheo, P. K.; Wagner, R.; Gilden, M.

1984-01-01

A parametric study was conducted to develop an electrooptic waveguide modulator for generating continuous tunable sideband power from an infrared CO2 laser. Parameters included were the waveguide configurations, microstrip dimensions device impedance, and effective dielectric constants. An optimum infrared laser modulator was established and was fabricated. This modulator represents the state-of-the-art integrated optical device, which has a three-dimensional topology to accommodate three lambda/4 step transformers for microwave impedance matching at both the input and output terminals. A flat frequency response of the device over 20 HGz or = 3 dB) was achieved. Maximum single sideband to carrier power greater than 1.2% for 20 W microwave input power at optical carrier wavelength of 10.6 microns was obtained.

Sideband analysis and seismic detection in a large ring laser

NASA Astrophysics Data System (ADS)

Stedman, G. E.; Li, Z.; Bilger, H. R.

1995-08-01

A ring laser unlocked by the Earth's Sagnac effect has attained a frequency resolution of 1 part in 3 \\times 1021 and a rotational resolution of 300 prad. We discuss both theoretically and experimentally the sideband structure of the Earth rotation-induced spectral line induced in the microhertz-hertz region by frequency modulation associated with extra mechanical motion, such as seismic events. The relative sideband height is an absolute measure of the rotational amplitude of that Fourier component. An initial analysis is given of the ring laser record from the Arthur's Pass-Coleridge seismic event of 18 June 1994.

47 CFR 2.201 - Emission, modulation, and transmission characteristics.

Code of Federal Regulations, 2014 CFR

2014-10-01

... carrier is amplitude-modulated (including cases where sub-carriers are angle-modulated): —Double-sideband... is amplitude and angle-modulated either simultaneously or in a pre-established sequence D (5) Emission of pulses: 1 —Sequence of unmodulated pulses P —A sequence of pulses: —Modulated in amplitude K...

47 CFR 2.201 - Emission, modulation, and transmission characteristics.

Code of Federal Regulations, 2013 CFR

2013-10-01

... carrier is amplitude-modulated (including cases where sub-carriers are angle-modulated): —Double-sideband... is amplitude and angle-modulated either simultaneously or in a pre-established sequence D (5) Emission of pulses: 1 —Sequence of unmodulated pulses P —A sequence of pulses: —Modulated in amplitude K...

47 CFR 2.201 - Emission, modulation, and transmission characteristics.

Code of Federal Regulations, 2012 CFR

2012-10-01

... carrier is amplitude-modulated (including cases where sub-carriers are angle-modulated): —Double-sideband... is amplitude and angle-modulated either simultaneously or in a pre-established sequence D (5) Emission of pulses: 1 —Sequence of unmodulated pulses P —A sequence of pulses: —Modulated in amplitude K...

Enhanced detection of a low-frequency signal by using broad squeezed light and a bichromatic local oscillator

NASA Astrophysics Data System (ADS)

Li, Wei; Jin, Yuanbin; Yu, Xudong; Zhang, Jing

2017-08-01

We experimentally study a protocol of using the broadband high-frequency squeezed vacuum to detect the low-frequency signal. In this scheme, the lower sideband field of the squeezed light carries the low-frequency modulation signal, and the two strong coherent light fields are applied as the bichromatic local oscillator in the homodyne detection to measure the quantum entanglement of the upper and lower sideband for the broadband squeezed light. The power of one of the local oscillators for detecting the upper sideband can be adjusted to optimize the conditional variance in the low-frequency regime by subtracting the photocurrent of the upper sideband field of the squeezed light from that of the lower sideband field. By means of the quantum correlation of the upper and lower sideband for the broadband squeezed light, the low-frequency signal beyond the standard quantum limit is measured. This scheme is appropriate for enhancing the sensitivity of the low-frequency signal by the aid of the broad squeezed light, such as gravitational waves detection, and does not need to directly produce the low-frequency squeezing in an optical parametric process.

Development of Bone-Conducted Ultrasonic Hearing Aid for the Profoundly Deaf: Assessments of the Modulation Type with Regard to Intelligibility and Sound Quality

NASA Astrophysics Data System (ADS)

Nakagawa, Seiji; Fujiyuki, Chika; Kagomiya, Takayuki

2012-07-01

Bone-conducted ultrasound (BCU) is perceived even by the profoundly sensorineural deaf. A novel hearing aid using the perception of amplitude-modulated BCU (BCU hearing aid: BCUHA) has been developed; however, further improvements are needed, especially in terms of articulation and sound quality. In this study, the intelligibility and sound quality of BCU speech with several types of amplitude modulation [double-sideband with transmitted carrier (DSB-TC), double-sideband with suppressed carrier (DSB-SC), and transposed modulation] were evaluated. The results showed that DSB-TC and transposed speech were more intelligible than DSB-SC speech, and transposed speech was closer than the other types of BCU speech to air-conducted speech in terms of sound quality. These results provide useful information for further development of the BCUHA.

The Hsp70 homolog Ssb and the 14-3-3 protein Bmh1 jointly regulate transcription of glucose repressed genes in Saccharomyces cerevisiae.

PubMed

Hübscher, Volker; Mudholkar, Kaivalya; Chiabudini, Marco; Fitzke, Edith; Wölfle, Tina; Pfeifer, Dietmar; Drepper, Friedel; Warscheid, Bettina; Rospert, Sabine

2016-07-08

Chaperones of the Hsp70 family interact with a multitude of newly synthesized polypeptides and prevent their aggregation. Saccharomyces cerevisiae cells lacking the Hsp70 homolog Ssb suffer from pleiotropic defects, among others a defect in glucose-repression. The highly conserved heterotrimeric kinase SNF1/AMPK (AMP-activated protein kinase) is required for the release from glucose-repression in yeast and is a key regulator of energy balance also in mammalian cells. When glucose is available the phosphatase Glc7 keeps SNF1 in its inactive, dephosphorylated state. Dephosphorylation depends on Reg1, which mediates targeting of Glc7 to its substrate SNF1. Here we show that the defect in glucose-repression in the absence of Ssb is due to the ability of the chaperone to bridge between the SNF1 and Glc7 complexes. Ssb performs this post-translational function in concert with the 14-3-3 protein Bmh, to which Ssb binds via its very C-terminus. Raising the intracellular concentration of Ssb or Bmh enabled Glc7 to dephosphorylate SNF1 even in the absence of Reg1. By that Ssb and Bmh efficiently suppressed transcriptional deregulation of Δreg1 cells. The findings reveal that Ssb and Bmh comprise a new chaperone module, which is involved in the fine tuning of a phosphorylation-dependent switch between respiration and fermentation. © The Author(s) 2016. Published by Oxford University Press on behalf of Nucleic Acids Research.

The Hsp70 homolog Ssb and the 14-3-3 protein Bmh1 jointly regulate transcription of glucose repressed genes in Saccharomyces cerevisiae

PubMed Central

Hübscher, Volker; Mudholkar, Kaivalya; Chiabudini, Marco; Fitzke, Edith; Wölfle, Tina; Pfeifer, Dietmar; Drepper, Friedel; Warscheid, Bettina; Rospert, Sabine

2016-01-01

Chaperones of the Hsp70 family interact with a multitude of newly synthesized polypeptides and prevent their aggregation. Saccharomyces cerevisiae cells lacking the Hsp70 homolog Ssb suffer from pleiotropic defects, among others a defect in glucose-repression. The highly conserved heterotrimeric kinase SNF1/AMPK (AMP-activated protein kinase) is required for the release from glucose-repression in yeast and is a key regulator of energy balance also in mammalian cells. When glucose is available the phosphatase Glc7 keeps SNF1 in its inactive, dephosphorylated state. Dephosphorylation depends on Reg1, which mediates targeting of Glc7 to its substrate SNF1. Here we show that the defect in glucose-repression in the absence of Ssb is due to the ability of the chaperone to bridge between the SNF1 and Glc7 complexes. Ssb performs this post-translational function in concert with the 14-3-3 protein Bmh, to which Ssb binds via its very C-terminus. Raising the intracellular concentration of Ssb or Bmh enabled Glc7 to dephosphorylate SNF1 even in the absence of Reg1. By that Ssb and Bmh efficiently suppressed transcriptional deregulation of Δreg1 cells. The findings reveal that Ssb and Bmh comprise a new chaperone module, which is involved in the fine tuning of a phosphorylation-dependent switch between respiration and fermentation. PMID:27001512

Modulation for terrestrial broadcasting of digital HDTV

NASA Technical Reports Server (NTRS)

Kohn, Elliott S.

1991-01-01

The digital modulation methods used by the DigiCipher, DSC-HDTV, ADTV, and ATVA-P digital high-definition television (HDTV) systems are discussed. Three of the systems use a quadrature amplitude modulation method, and the fourth uses a vestigial sideband modulation method. The channel equalization and spectrum sharing of the digital HDTV systems is discussed.

Absolute-length determination of a long-baseline Fabry-Perot cavity by means of resonating modulation sidebands.

PubMed

Araya, A; Telada, S; Tochikubo, K; Taniguchi, S; Takahashi, R; Kawabe, K; Tatsumi, D; Yamazaki, T; Kawamura, S; Miyoki, S; Moriwaki, S; Musha, M; Nagano, S; Fujimoto, M K; Horikoshi, K; Mio, N; Naito, Y; Takamori, A; Yamamoto, K

1999-05-01

A new method has been demonstrated for absolute-length measurements of a long-baseline Fabry-Perot cavity by use of phase-modulated light. This method is based on determination of a free spectral range (FSR) of the cavity from the frequency difference between a carrier and phase-modulation sidebands, both of which resonate in the cavity. Sensitive response of the Fabry-Perot cavity near resonant frequencies ensures accurate determination of the FSR and thus of the absolute length of the cavity. This method was applied to a 300-m Fabry-Perot cavity of the TAMA gravitational wave detector that is being developed at the National Astronomical Observatory, Tokyo. With a modulation frequency of approximately 12 MHz, we successfully determined the absolute cavity length with resolution of 1 microm (3 x 10(-9) in strain) and observed local ground strain variations of 6 x 10(-8).

47 CFR 73.322 - FM stereophonic sound transmission standards.

Code of Federal Regulations, 2010 CFR

2010-10-01

... frequency in a transmission system meeting the following parameters: (1) The modulating signal for the main... frequency modulate the main carrier between the limits of 8 and 10 percent. (3) One stereophonic subcarrier... stereophomic subcarriers are not precluded. (4) Double sideband, suppressed-carrier, amplitude modulation of...

Permanent tooth loss and sugar-sweetened beverage intake in U.S. young adults.

PubMed

Kim, Sunkyung; Park, Sohyun; Lin, Mei

2017-03-01

In young adults, sugar-sweetened beverage (SSB) intake is associated with dental caries, which in turn is a major contributor to tooth loss. The independent role of SSB intake on tooth loss, however, has not been well-described. This cross-sectional study examined associations between tooth loss and SSB intake among U.S. young adults. The outcome was number of permanent teeth lost because of dental caries or periodontal disease (0, 1-5, ≥6 teeth). Data from the 2012 Behavioral Risk Factor Surveillance System were used. The 22,526 adults aged 18-39 years completed the Sugar Drink Module. The exposure variable was daily frequency of SSB intake. We used multinomial logistic regression to examine the adjusted associations between tooth loss and daily SSB consumption (0, >0 to <1, 1-2, >2 times/day). Approximately, 26% of young adults reported losing at least one permanent tooth. Tooth loss was positively associated with SSB intake frequency; the odds of losing 1-5 teeth were higher among adults drinking SSBs >0-<1 times/day (OR = 1.44, 95%CI = 1.16-1.79), 1-2 times/day (OR = 1.58, 95%CI = 1.25-1.99), and >2 times/day (OR = 1.97, 95%CI = 1.51-2.58) than non-SSB consumers. The odds of losing ≥6 teeth were higher among adults drinking SSBs 1-2 times/day (OR = 2.20, 95%CI = 1.15-4.22) and >2 times/day (OR = 2.81, 95%CI = 1.37-5.76) than non-SSB consumers. Frequency of SSB consumption was positively associated with tooth loss among young adults even when the average SSB intake was less than one time per day. This study suggests that efforts to reduce SSB intake among young adults may help to decrease the risk of tooth loss. © 2016 American Association of Public Health Dentistry.

Chirped-pulse coherent-OTDR with predistortion

NASA Astrophysics Data System (ADS)

Xiong, Ji; Jiang, Jialin; Wu, Yue; Chen, Yongxiang; Xie, Lianlian; Fu, Yun; Wang, Zinan

2018-03-01

In this paper, a novel method for generating high-quality chirped pulses with IQ modulator is studied theoretically and experimentally, which is a crucial building block for high-performance coherent optical time-domain reflectometry (COTDR). In order to compensate the nonlinearity of the modulator transfer function, we present a predistortion technique for chirped-pulse coherent optical time-domain reflectometry (CP-COTDR), the arcsin predistortion method and the single sideband with a suppressed carrier analog modulation used to generate the high quality chirped optical pulse. The high order sidebands, due to the large amplitude of the modulation signal and the nonlinear transfer function of the IQ modulator, can be relieved by the predistortion process, which means the power and the quality of the generated chirped pulse has been improved. In the experiment, this method increases the peak power of the chirped pulse by 4.2 dB compared to the case without predistortion process, as for the CP-COTDR system, this method increases the signal-to-noise ratio of the demodulated phase variation by 6.3 dB.

Heat shock proteins MoSsb1, MoSsz1, and MoZuo1 attenuate MoMkk1-mediated CWI signaling and are important for growth and pathogenicity of Magnaporthe oryzae.

PubMed

Yang, Jie; Liu, Muxing; Liu, Xinyu; Yin, Ziyi; Sun, Yi; Zhang, Haifeng; Zheng, Xiaobo; Wang, Ping; Zhang, Zhengguang

2018-06-05

The mitogen-activated protein (MAP) kinase MoMkk1 governs the cell wall integrity (CWI) pathway in the rice blast fungus Magnaporthe oryzae. To understand the underlying mechanism, we have identified MoSsb1 as one of the MoMkk1-interacting proteins. MoSsb1 is a stress-seventy subfamily B (Ssb) protein homolog, sharing high amino acid sequence homology with the 70-kDa heat shock proteins (Hsp70s). Hsp70 proteins are a family of conserved and ubiquitously expressed chaperones that regulate protein biogenesis by promoting protein folding, preventing protein aggregation and controlling protein degradation. We found that MoSsb1 regulates the synthesis of nascent polypeptide chains and this regulation is achieved by being in complex with other members of heat shock proteins: Hsp70 MoSsz1 and 40-kDa heat shock protein (Hsp40) MoZuo1. MoSsb1 is important for the growth, conidiation and full virulence of the blast fungus and this role is also shared by MoSsz1 and MoZuo1. Importantly, MoSsb1, MoSsz1 and MoZuo1 are all involved in the regulation of the CWI MAP kinase pathway by modulating MoMkk1 biosynthesis. Our studies reveal novel insights into how MoSsb1, MoSsz1 and MoZuo1 affect CWI signaling that is involved in regulating growth, differentiation and virulence of M. oryzae and highlight the conserved functional mechanisms of Hsp proteins in pathogenic fungi.

Single mode CO2 laser frequency modulation up to 350 MHz

NASA Technical Reports Server (NTRS)

Leeb, W. R.; Peruso, C. J.

1977-01-01

Experiments on internal frequency modulation (FM) of a CO2 laser showed no limitation of FM by the linewidth. However, distortions in the form of strong enhancement of sideband amplitude arise for frequencies equal to the cavity resonant frequencies, most pronounced if the modulator is positioned near a cavity mirror.

47 CFR 73.758 - System specifications for digitally modulated emissions in the HF broadcasting service.

Code of Federal Regulations, 2010 CFR

2010-10-01

... this paragraph. (4) Modulation. Quadrature amplitude modulation (QAM) with orthogonal frequency... frequency broadcasting (HFBC) band, provided the protection afforded to the analog emissions is at least as... used for either DSB or SSB emissions. (c) Emission characteristics—(1) Bandwidth and center frequency...

Multi-photon transitions and Rabi resonance in continuous wave EPR.

PubMed

Saiko, Alexander P; Fedaruk, Ryhor; Markevich, Siarhei A

2015-10-01

The study of microwave-radiofrequency multi-photon transitions in continuous wave (CW) EPR spectroscopy is extended to a Rabi resonance condition, when the radio frequency of the magnetic-field modulation matches the Rabi frequency of a spin system in the microwave field. Using the non-secular perturbation theory based on the Bogoliubov averaging method, the analytical description of the response of the spin system is derived for all modulation frequency harmonics. When the modulation frequency exceeds the EPR linewidth, multi-photon transitions result in sidebands in absorption EPR spectra measured with phase-sensitive detection at any harmonic. The saturation of different-order multi-photon transitions is shown to be significantly different and to be sensitive to the Rabi resonance. The noticeable frequency shifts of sidebands are found to be the signatures of this resonance. The inversion of two-photon lines in some spectral intervals of the out-of-phase first-harmonic signal is predicted under passage through the Rabi resonance. The inversion indicates the transition from absorption to stimulated emission or vice versa, depending on the sideband. The manifestation of the primary and secondary Rabi resonance is also demonstrated in the time evolution of steady-state EPR signals formed by all harmonics of the modulation frequency. Our results provide a theoretical framework for future developments in multi-photon CW EPR spectroscopy, which can be useful for samples with long spin relaxation times and extremely narrow EPR lines. Copyright © 2015 Elsevier Inc. All rights reserved.

Brillouin Amplification--A Powerful New Scheme for Microwave Photonic Communications

NASA Technical Reports Server (NTRS)

Yao, S.; Maleki, L.

1997-01-01

We introduce the Brillouin selective sideband amplification technique and demonstrate many important applications of this technique in photonic microwave systems, including efficient phase modulation to amplitude modulation conversion, photonic frequency multiplication, photonic signal mixing with gain, and frequency multiplied signal up conversion.

Project Echo: 960-Megacycle, 10-Kilowatt Transmitter

NASA Technical Reports Server (NTRS)

Schafer, J. P.; Brandt, R. H.

1961-01-01

A 10-kw transmitter operating at 960 to 961 Mc was used at the eastern terminus of the Project Echo communications experiment. This transmitter is located on Crawford's Hill near Holmdel, New Jersey. The 10-kw output feeds into a waveguide line leading to a 60-foot dish antenna. Exciter-driver units are available to drive the power amplifier with various modulations, such as wide-deviation FM, low-index phase modulation, single-sideband or double-sideband modulation with or without carrier, 960.05 or 961.05 Mc constant-frequency CW, and radar on-off pulses at 961.05 Mc. The main output amplifier consists primarily of a four-stage, externally-tuned-cavity, water-cooled klystron, operating at a beam voltage of 16 to 18 kv. The transmitter has been operated during many Moonbounce, tropospheric scatter, and Echo I tests with very satisfactory results. This paper describes its use before March 1, 1961.

Optical Sidebands Multiplier

NASA Technical Reports Server (NTRS)

Strekalov, Dmitry V.; Yu, Nan

2010-01-01

Optical sidebands have been generated with relative frequency tens to hundreds of GHz by using optical sidebands that are generated in a cascade process in high-quality optical resonators with Kerr nonlinearity, such as whispering gallery mode (WGM) resonators. For this purpose, the WGM resonator needs to be optically pumped at two frequencies matching its resonances. These two optical components can be one or several free spectral ranges (FSRs), equal to approximately 12 GHz, in this example, apart from each other, and can be easily derived from a monochromatic pump with an ordinary EOM (electro-optic modulation) operating at half the FSR frequency. With sufficient nonlinearity, an optical cascade process will convert the two pump frequencies into a comb-like structure extending many FSRs around the carrier frequency. This has a demonstratively efficient frequency conversion of this type with only a few milliwatt optical pump power. The concept of using Kerr nonlinearity in a resonator for non-degenerate wave mixing has been discussed before, but it was a common belief that this was a weak process requiring very high peak powers to be observable. It was not thought possible for this approach to compete with electro-optical modulators in CW applications, especially those at lower optical powers. By using the high-Q WGM resonators, the effective Kerr nonlinearity can be made so high that, using even weak seeding bands available from a conventional EOM, one can effectively multiply the optical sidebands, extending them into an otherwise inaccessible frequency range.

Synchronous radio-frequency FM signal generator using direct digital synthesizers

NASA Astrophysics Data System (ADS)

Arablu, Masoud; Kafashi, Sajad; Smith, Stuart T.

2018-04-01

A novel Radio-Frequency Frequency-Modulated (RF-FM) signal generation method is introduced and a prototype circuit developed to evaluate its functionality and performance. The RF-FM signal generator uses a modulated, voltage-controlled time delay to correspondingly modulate the phase of a 10 MHz sinusoidal reference signal. This modulated reference signal is, in turn, used to clock a Direct Digital Synthesizer (DDS) circuit resulting in an FM signal at its output. The modulating signal that is input to the voltage-controlled time delay circuit is generated by another DDS that is synchronously clocked by the same 10 MHz sine wave signal before modulation. As a consequence, all of the digital components are timed from a single sine wave oscillator that forms the basis of all timing. The resultant output signal comprises a center, or carrier, frequency plus a series of phase-synchronized sidebands having exact integer harmonic frequency separation. In this study, carrier frequencies ranging from 10 MHz to 70 MHz are generated with modulation frequencies ranging from 10 kHz to 300 kHz. The captured spectra show that the FM signal characteristics, amplitude and phase, of the sidebands and the modulation depth are consistent with the Jacobi-Anger expansion for modulated harmonic signals.

Double-sideband frequency scanning interferometry for long-distance dynamic absolute measurement

NASA Astrophysics Data System (ADS)

Mo, Di; Wang, Ran; Li, Guang-zuo; Wang, Ning; Zhang, Ke-shu; Wu, Yi-rong

2017-11-01

Absolute distance measurements can be achieved by frequency scanning interferometry which uses a tunable laser. The main drawback of this method is that it is extremely sensitive to the movement of targets. In addition, since this method is limited to the linearity of frequency scanning, it is commonly used for close measurements within tens of meters. In order to solve these problems, a double-sideband frequency scanning interferometry system is presented in the paper. It generates two opposite frequency scanning signals through a fixed frequency laser and a Mach-Zehnder modulator. And the system distinguishes the two interference fringe patterns corresponding to the two signals by IQ demodulation (i.e., quadrature detection) of the echo. According to the principle of double-sideband modulation, the two signals have the same characteristics. Therefore, the error caused by the target movement can be effectively eliminated, which is similar to dual-laser frequency scanned interferometry. In addition, this method avoids the contradiction between laser frequency stability and swept performance. The system can be applied to measure the distance of the order of kilometers, which profits from the good linearity of frequency scanning. In the experiment, a precision about 3 μm was achieved for a kilometer-level distance.

High efficiency tapered free-electron lasers with a prebunched electron beam

DOE PAGES

Emma, C.; Sudar, N.; Musumeci, P.; ...

2017-11-17

In this study we analyze the high gain, high efficiency tapered free-electron laser amplifier with a prebunched electron beam. Simple scaling laws are derived for the peak output power and extraction efficiency and verified using 1D simulations. These studies provide useful analytical expressions which highlight the benefits resulting from fine control of the initial conditions of the system, namely the initial electron beam bunching and input seed radiation. When time-dependent effects are included, the sideband instability is known to limit the radiation amplification due to particle detrapping. We discuss two different approaches to mitigate the sideband growth via 1-D timemore » dependent simulations. We find that a more aggressive taper enabled by strong prebunching and a modulation of the resonance condition are both effective methods for suppressing the sideband instability growth rate.« less

Wideband tunable laser phase noise reduction using single sideband modulation in an electro-optical feed-forward scheme.

PubMed

Aflatouni, Firooz; Hashemi, Hossein

2012-01-15

A wideband laser phase noise reduction scheme is introduced where the optical field of a laser is single sideband modulated with an electrical signal containing the discriminated phase noise of the laser. The proof-of-concept experiments on a commercially available 1549 nm distributed feedback laser show linewidth reduction from 7.5 MHz to 1.8 kHz without using large optical cavity resonators. This feed-forward scheme performs wideband phase noise cancellation independent of the light source and, as such, it is compatible with the original laser source tunability without requiring tunable optical components. By placing the proposed phase noise reduction system after a commercial tunable laser, a tunable coherent light source with kilohertz linewidth over a tuning range of 1530-1570 nm is demonstrated.

Electronic sideband locking of a broadly tunable 318.6 nm ultraviolet laser to an ultra-stable optical cavity

NASA Astrophysics Data System (ADS)

Bai, Jiandong; Wang, Jieying; He, Jun; Wang, Junmin

2017-04-01

We demonstrate frequency stabilization of a tunable 318.6 nm ultraviolet (UV) laser system using electronic sideband locking. By indirectly changing the frequency of a broadband electro-optic phase modulator, the laser can be continuously tuned over 4 GHz, while a 637.2 nm laser is directly stabilized to a high-finesse ultra-stable optical cavity. The doubling cavity also remains locked to the 637.2 nm light. We show that the tuning range depends mainly on the gain-flattening region of the modulator and the piezo-tunable range of the seed laser. The frequency-stabilized tunable UV laser system is able to compensate for the offset between reference and target frequencies, and has potential applications in precision spectroscopy of cold atoms.

Accuracy enhanced distance measurement system using double-sideband modulated frequency scanning interferometry

NASA Astrophysics Data System (ADS)

Chen, Xilun; Wang, Xiangchuan; Pan, Shilong

2017-03-01

An implementation of a distance measurement system using double-sideband with suppressed carrier modulation (DSB-SC) frequency scanning interferometry is proposed to reduce the variations in the optical path and improve the measurement accuracy. In this proposed system, the electro-optic DSB-SC is used to create dual-swept signals with opposite scanning directions. For each swept signal, the relative distance between the reference arm and the measuring arm is determined by the beat frequency of signals from two arms. By multiplying both beat signals, measurement errors caused by variations in the optical path can be greatly reduced. As an experimental demonstration, a vibration was introduced in the optical path length. The experimental results show that the variations can be suppressed for over 19.9 dB.

47 CFR 95.639 - Maximum transmitter power.

Code of Federal Regulations, 2010 CFR

2010-10-01

...) No GMRS transmitter, under any condition of modulation, shall exceed: (1) 50 W Carrier power (average... transmitter, under any condition of modulation, shall exceed a carrier power or peak envelope TP (single-sideband only) of: (1) 4 W in the 26-27 MHz frequency band, except on channel frequency 27.255 MHz; (2) 25...

Quantitative proton magnetic resonance spectroscopy without water suppression

NASA Astrophysics Data System (ADS)

Özdemir, M. S.; DeDeene, Y.; Fieremans, E.; Lemahieu, I.

2009-06-01

The suppression of the abundant water signal has been traditionally employed to decrease the dynamic range of the NMR signal in proton MRS (1H MRS) in vivo. When using this approach, if the intent is to utilize the water signal as an internal reference for the absolute quantification of metabolites, additional measurements are required for the acquisition of the water signal. This can be prohibitively time-consuming and is not desired clinically. Additionally, traditional water suppression can lead to metabolite alterations. This can be overcome by performing quantitative 1H MRS without water suppression. However, the non-water-suppressed spectra suffer from gradient-induced frequency modulations, resulting in sidebands in the spectrum. Sidebands may overlap with the metabolites, which renders the spectral analysis and quantification problematic. In this paper, we performed absolute quantification of metabolites without water suppression. Sidebands were removed by utilizing the phase of an external reference signal of single resonance to observe the time-varying the static field fluctuations induced by gradient-vibration and deconvolving this phase contamination from the desired NMR signal. The quantification of metabolites was determined after sideband correction by calibrating the metabolite signal intensities against the recorded water signal. The method was evaluated by phantom and in vivo measurements in human brain. The maximum systematic error for the quantified metabolite concentrations was found to be 10.8%, showing the feasibility of the quantification after sideband correction.

Coupling of a nanomechanical oscillator and an atomic three-level medium

NASA Astrophysics Data System (ADS)

Sanz-Mora, A.; Eisfeld, A.; Wüster, S.; Rost, J.-M.

2016-02-01

We theoretically investigate the coupling of an ultracold three-level atomic gas and a nanomechanical mirror via classical electromagnetic radiation. The radiation pressure on the mirror is modulated by absorption of a probe light field, caused by the atoms which are electromagnetically rendered nearly transparent, allowing the gas to affect the mirror. In turn, the mirror can affect the gas as its vibrations generate optomechanical sidebands in the control field. We show that the sidebands cause modulations of the probe intensity at the mirror frequency, which can be enhanced near atomic resonances. Through the radiation pressure from the probe beam onto the mirror, this results in resonant driving of the mirror. Controllable by the two-photon detuning, the phase relation of the driving to the mirror motion decides upon amplification or damping of mirror vibrations. This permits direct phase locking of laser amplitude modulations to the motion of a nanomechanical element opening a perspective for cavity-free cooling through coupling to an atomic gas.

Photonics-based microwave frequency measurement using a double-sideband suppressed-carrier modulation and an InP integrated ring-assisted Mach-Zehnder interferometer filter.

PubMed

Fandiño, Javier S; Muñoz, Pascual

2013-11-01

A photonic system capable of estimating the unknown frequency of a CW microwave tone is presented. The core of the system is a complementary optical filter monolithically integrated in InP, consisting of a ring-assisted Mach-Zehnder interferometer with a second-order elliptic response. By simultaneously measuring the different optical powers produced by a double-sideband suppressed-carrier modulation at the outputs of the photonic integrated circuit, an amplitude comparison function that depends on the input tone frequency is obtained. Using this technique, a frequency measurement range of 10 GHz (5-15 GHz) with a root mean square value of frequency error lower than 200 MHz is experimentally demonstrated. Moreover, simulations showing the impact of a residual optical carrier on system performance are also provided.

The yeast Hsp70 homolog Ssb: a chaperone for general de novo protein folding and a nanny for specific intrinsically disordered protein domains.

PubMed

Hübscher, Volker; Mudholkar, Kaivalya; Rospert, Sabine

2017-02-01

Activation of the heterotrimeric kinase SNF1 via phosphorylation of a specific residue within the α subunit is essential for the release from glucose repression in the yeast Saccharomyces cerevisiae. When glucose is available, SNF1 is maintained in the dephosphorylated, inactive state by the phosphatase Glc7-Reg1. Recent findings suggest that Bmh and Ssb combine their unique client-binding properties to interact with the regulatory region of the SNF1 α subunit and by that stabilize a conformation of SNF1, which is accessible for Glc7-Reg1-dependent dephosphorylation. Together, the 14-3-3 protein Bmh and the Hsp70 homolog Ssb comprise a novel chaperone module, which is required to maintain proper glucose repression in the yeast S. cerevisiae.

Microwave generation with photonic frequency octupling using a DPMZM in a Sagnac loop

NASA Astrophysics Data System (ADS)

Gao, Yongsheng; Wen, Aijun; Li, Ningning; Wu, Xiaohui; Zhang, Huixing

2015-09-01

A photonic microwave signal generation scheme with frequency octupling is proposed and experimentally demonstrated. The scheme is based on bi-directional use of a dual-parallel Mach-Zehnder modulator (DPMZM) in a Sagnac loop. The two sub-modulators in the DPMZM are driven by two low-frequency signals with a π/2 phase difference, and the dc biases of the modulator are all set at the maximum transmission points. Due to the velocity mismatch of the modulator, only the light wave along the clockwise direction is effectively modulated by the drive signals to generate an optical signal with a carrier and ±4th order sidebands, while the modulation of the light wave along the counterclockwise direction is far less effective and can be ignored. By properly adjusting the polarization of the light wave output from the Sagnac loop, the optical carrier can be significantly suppressed at a polarizer, and then an optical signal with only ±4th order sidebands is generated. In the experiment, a pure 24-GHz microwave signal without additional phase noise from the optical system is generated using a 3-GHz local oscillator signal. As no electrical or optical filter is used, the photonic frequency octupler is of good frequency tunability.

Generation and Amplification of Tunable Multicolored Femtosecond Laser Pulses by Using Cascaded Four-Wave Mixing in Transparent Bulk Media

PubMed Central

Liu, Jun; Kobayashi, Takayoshi

2010-01-01

We have reviewed the generation and amplification of wavelength-tunable multicolored femtosecond laser pulses using cascaded four-wave mixing (CFWM) in transparent bulk media, mainly concentrating on our recent work. Theoretical analysis and calculations based on the phase-matching condition could explain well the process semi-quantitatively. The experimental studies showed: (1) as many as fifteen spectral up-shifted and two spectral down-shifted sidebands were obtained simultaneously with spectral bandwidth broader than 1.8 octaves from near ultraviolet (360 nm) to near infrared (1.2 μm); (2) the obtained sidebands were spatially separated well and had extremely high beam quality with M2 factor better than 1.1; (3) the wavelengths of the generated multicolor sidebands could be conveniently tuned by changing the crossing angle or simply replacing with different media; (4) as short as 15-fs negatively chirped or nearly transform limited 20-fs multicolored femtosecond pulses were obtained when one of the two input beams was negatively chirped and the other was positively chirped; (5) the pulse energy of the sideband can reach a μJ level with power stability better than 1% RMS; (6) broadband two-dimensional (2-D) multicolored arrays with more than ten periodic columns and more than ten rows were generated in a sapphire plate; (7) the obtained sidebands could be simultaneously spectra broadened and power amplified in another bulk medium by using cross-phase modulation (XPM) in conjunction with four-wave optical parametric amplification (FOPA). The characterization showed that this is interesting and the CFWM sidebands generated by this novel method have good enough qualities in terms of power stability, beam quality, and temporal features suited to various experiments such as ultrafast multicolor time-resolved spectroscopy and multicolor-excitation nonlinear microscopy. PMID:22399882

Security of subcarrier wave quantum key distribution against the collective beam-splitting attack.

PubMed

Miroshnichenko, G P; Kozubov, A V; Gaidash, A A; Gleim, A V; Horoshko, D B

2018-04-30

We consider a subcarrier wave quantum key distribution (QKD) system, where quantum encoding is carried out at weak sidebands generated around a coherent optical beam as a result of electro-optical phase modulation. We study security of two protocols, B92 and BB84, against one of the most powerful attacks for this class of systems, the collective beam-splitting attack. Our analysis includes the case of high modulation index, where the sidebands are essentially multimode. We demonstrate numerically and experimentally that a subcarrier wave QKD system with realistic parameters is capable of distributing cryptographic keys over large distances in presence of collective attacks. We also show that BB84 protocol modification with discrimination of only one state in each basis performs not worse than the original BB84 protocol in this class of QKD systems, thus significantly simplifying the development of cryptographic networks using the considered QKD technique.

Wavelength reused bidirectional transmission of adaptively modulated optical OFDM signals in WDM-PONs incorporating SOA and RSOA intensity modulators.

PubMed

Wei, J L; Hugues-Salas, E; Giddings, R P; Jin, X Q; Zheng, X; Mansoor, S; Tang, J M

2010-05-10

Detailed numerical investigations are undertaken of wavelength reused bidirectional transmission of adaptively modulated optical OFDM (AMOOFDM) signals over a single SMF in a colorless WDM-PON incorporating a semiconductor optical amplifier (SOA) intensity modulator and a reflective SOA (RSOA) intensity modulator in the optical line termination and optical network unit, respectively. A comprehensive theoretical model describing the performance of such network scenarios is, for the first time, developed, taking into account dynamic optical characteristics of SOA and RSOA intensity modulators as well as the effects of Rayleigh backscattering (RB) and residual downstream signal-induced crosstalk. The developed model is rigorously verified experimentally in RSOA-based real-time end-to-end OOFDM systems at 7.5 Gb/s. It is shown that the RB noise and crosstalk effects are dominant factors limiting the maximum achievable downstream and upstream transmission performance. Under optimum SOA and RSOA operating conditions as well as practical downstream and upstream optical launch powers, 10 Gb/s downstream and 6 Gb/s upstream over 40 km SMF transmissions of conventional double sideband AMOOFDM signals are feasible without utilizing in-line optical amplification and chromatic dispersion compensation. In particular, the aforementioned transmission performance can be improved to 23 Gb/s downstream and 8 Gb/s upstream over 40 km SMFs when single sideband subcarrier modulation is adopted in the downstream systems. (c) 2010 Optical Society of America.

Coherent Fiber Optic Links

DTIC Science & Technology

1990-12-01

since drift is common to both signal and local oscillator. However because of the Fabry - Perot cavity of the phase -6.9- Electrical delay 5.429077 ns___...Phase modulation gives intensity modulation of the guided light of .13dB max. This is due to formation of a Fabry - Perot cavity between the two fibre/chip...modulation sidebands using an optical spectrum analyser (scanning a Fabry - Perot interferometer), while monitoring the r.f. drive power incident on the

Optical millimeter-wave signal generation by frequency quadrupling using one dual-drive Mach-Zehnder modulator to overcome chromatic dispersion

NASA Astrophysics Data System (ADS)

Zhu, Zihang; Zhao, Shanghong; Yao, Zhoushi; Tan, Qinggui; Li, Yongjun; Chu, Xingchun; Shi, Lei; Zhang, Xi

2012-06-01

We propose a novel approach to generate quadrupling-frequency optical millimeter-wave using a dual-drive Mach-Zehnder modulator (MZM) in radio-over-fiber system. By properly adjusting the phase difference in the two modulation arms of MZM, the direct current (DC) bias, the modulation index and the gain of base-band signal, the quadrupling-frequency optical millimeter-wave with signal only carried by one second-order sideband is generated. As the signal is transmitted along the fiber, there is no time shift of the codes caused by chromatic dispersion. Theoretical analysis and simulation results show that the eye diagram keeps open and clear even when the quadrupling-frequency optical millimeter-wave are transmitted over 110 km and the power penalty is about 0.45 dB after fiber transmission distance of 60 km. Furthermore, due to another second-order sideband carrying no signals, a full duplex radio-over-fiber link based on wavelength reuse is also built to simplify the base station. The bidirectional 2.5 Gbit/s data is successfully transmitted over 40 km standard single mode fiber with less than 0.6 dB power penalty in the simulation.

Special Semaphore Scheme for UHF Spacecraft Communications

NASA Technical Reports Server (NTRS)

Butman, Stanley; Satorius, Edgar; Ilott, Peter

2006-01-01

A semaphore scheme has been devised to satisfy a requirement to enable ultrahigh- frequency (UHF) radio communication between a spacecraft descending from orbit to a landing on Mars and a spacecraft, in orbit about Mars, that relays communications between Earth and the lander spacecraft. There are also two subsidiary requirements: (1) to use UHF transceivers, built and qualified for operation aboard the spacecraft that operate with residual-carrier binary phase-shift-keying (BPSK) modulation at a selectable data rate of 8, 32, 128, or 256 kb/s; and (2) to enable low-rate signaling even when received signals become so weak as to prevent communication at the minimum BPSK rate of 8 kHz. The scheme involves exploitation of Manchester encoding, which is used in conjunction with residual-carrier modulation to aid the carrier-tracking loop. By choosing various sequences of 1s, 0s, or 1s alternating with 0s to be fed to the residual-carrier modulator, one would cause the modulator to generate sidebands at a fundamental frequency of 4 or 8 kHz and harmonics thereof. These sidebands would constitute the desired semaphores. In reception, the semaphores would be detected by a software demodulator.

Phase matching as a gate for photon entanglement

PubMed Central

Zheltikov, A. M.

2017-01-01

Phase matching is shown to provide a tunable gate that helps discriminate entangled states of light generated by four-wave mixing (FWM) in optical fibers against uncorrelated photons originating from Raman scattering. Two types of such gates are discussed. Phase-matching gates of the first type are possible in the normal dispersion regime, where FWM sidebands can be widely tuned by high-order dispersion management, enhancing the ratio of the entangled-photon output to the Raman noise. The photon-entanglement gates of the second type are created by dual-pump cross-phase-modulation-induced FWM sideband generation and can be tuned by group-velocity mismatch of the pump fields. PMID:28703217

Spectral line-by-line pulse shaping of on-chip microresonator frequency combs

NASA Astrophysics Data System (ADS)

Ferdous, Fahmida; Miao, Houxun; Leaird, Daniel E.; Srinivasan, Kartik; Wang, Jian; Chen, Lei; Varghese, Leo Tom; Weiner, Andrew M.

2011-12-01

Recently, on-chip comb generation methods based on nonlinear optical modulation in ultrahigh-quality-factor monolithic microresonators have been demonstrated, where two pump photons are transformed into sideband photons in a four-wave-mixing process mediated by Kerr nonlinearity. Here, we investigate line-by-line pulse shaping of such combs generated in silicon nitride ring resonators. We observe two distinct paths to comb formation that exhibit strikingly different time-domain behaviours. For combs formed as a cascade of sidebands spaced by a single free spectral range that spread from the pump, we are able to compress stably to nearly bandwidth-limited pulses. This indicates high coherence across the spectra and provides new data on the high passive stability of the spectral phase. For combs where the initial sidebands are spaced by multiple free spectral ranges that then fill in to give combs with single free-spectral-range spacing, the time-domain data reveal partially coherent behaviour.

Absolute optical metrology : nanometers to kilometers

NASA Technical Reports Server (NTRS)

Dubovitsky, Serge; Lay, O. P.; Peters, R. D.; Liebe, C. C.

2005-01-01

We provide and overview of the developments in the field of high-accuracy absolute optical metrology with emphasis on space-based applications. Specific work on the Modulation Sideband Technology for Absolute Ranging (MSTAR) sensor is described along with novel applications of the sensor.

47 CFR 73.756 - System specifications for double-sideband (DBS) modulated emissions in the HF broadcasting service.

Code of Federal Regulations, 2014 CFR

2014-10-01

.... Nominal carrier frequencies shall be integral multiples of 5 kHz. (2) Audio-frequency band. The upper limit of the audio-frequency band (at—3 dB) of the transmitter shall not exceed 4.5 kHz and the lower... processing. If audio-frequency signal processing is used, the dynamic range of the modulating signal shall be...

47 CFR 73.756 - System specifications for double-sideband (DBS) modulated emissions in the HF broadcasting service.

Code of Federal Regulations, 2012 CFR

2012-10-01

.... Nominal carrier frequencies shall be integral multiples of 5 kHz. (2) Audio-frequency band. The upper limit of the audio-frequency band (at—3 dB) of the transmitter shall not exceed 4.5 kHz and the lower... processing. If audio-frequency signal processing is used, the dynamic range of the modulating signal shall be...

47 CFR 73.756 - System specifications for double-sideband (DBS) modulated emissions in the HF broadcasting service.

Code of Federal Regulations, 2011 CFR

2011-10-01

.... Nominal carrier frequencies shall be integral multiples of 5 kHz. (2) Audio-frequency band. The upper limit of the audio-frequency band (at—3 dB) of the transmitter shall not exceed 4.5 kHz and the lower... processing. If audio-frequency signal processing is used, the dynamic range of the modulating signal shall be...

47 CFR 73.756 - System specifications for double-sideband (DBS) modulated emissions in the HF broadcasting service.

Code of Federal Regulations, 2013 CFR

2013-10-01

.... Nominal carrier frequencies shall be integral multiples of 5 kHz. (2) Audio-frequency band. The upper limit of the audio-frequency band (at—3 dB) of the transmitter shall not exceed 4.5 kHz and the lower... processing. If audio-frequency signal processing is used, the dynamic range of the modulating signal shall be...

47 CFR 78.103 - Emissions and emission limitations.

Code of Federal Regulations, 2010 CFR

2010-10-01

...) Amplitude Modulation: For vestigial sideband AM video: On any frequency removed from the center frequency of...) Maximum authorized band-width (MHz) 1,990 to 2,110 17 or 18.1 6,425 to 6,525 8 or 25. 6,875 to 7,125 25...

47 CFR 78.103 - Emissions and emission limitations.

Code of Federal Regulations, 2014 CFR

2014-10-01

...) Amplitude Modulation: For vestigial sideband AM video: On any frequency removed from the center frequency of...) Maximum authorized band-width (MHz) 1,990 to 2,110 17 or 18.1 6,425 to 6,525 8 or 25. 6,875 to 7,125 25...

47 CFR 78.103 - Emissions and emission limitations.

Code of Federal Regulations, 2013 CFR

2013-10-01

...) Amplitude Modulation: For vestigial sideband AM video: On any frequency removed from the center frequency of...) Maximum authorized band-width (MHz) 1,990 to 2,110 17 or 18.1 6,425 to 6,525 8 or 25. 6,875 to 7,125 25...

47 CFR 78.103 - Emissions and emission limitations.

Code of Federal Regulations, 2012 CFR

2012-10-01

...) Amplitude Modulation: For vestigial sideband AM video: On any frequency removed from the center frequency of...) Maximum authorized band-width (MHz) 1,990 to 2,110 17 or 18.1 6,425 to 6,525 8 or 25. 6,875 to 7,125 25...

47 CFR 78.103 - Emissions and emission limitations.

Code of Federal Regulations, 2011 CFR

2011-10-01

...) Amplitude Modulation: For vestigial sideband AM video: On any frequency removed from the center frequency of...) Maximum authorized band-width (MHz) 1,990 to 2,110 17 or 18.1 6,425 to 6,525 8 or 25. 6,875 to 7,125 25...

Wideband optical vector network analyzer based on optical single-sideband modulation and optical frequency comb.

PubMed

Xue, Min; Pan, Shilong; He, Chao; Guo, Ronghui; Zhao, Yongjiu

2013-11-15

A novel approach to increase the measurement range of the optical vector network analyzer (OVNA) based on optical single-sideband (OSSB) modulation is proposed and experimentally demonstrated. In the proposed system, each comb line in an optical frequency comb (OFC) is selected by an optical filter and used as the optical carrier for the OSSB-based OVNA. The frequency responses of an optical device-under-test (ODUT) are thus measured channel by channel. Because the comb lines in the OFC have fixed frequency spacing, by fitting the responses measured in all channels together, the magnitude and phase responses of the ODUT can be accurately achieved in a large range. A proof-of-concept experiment is performed. A measurement range of 105 GHz and a resolution of 1 MHz is achieved when a five-comb-line OFC with a frequency spacing of 20 GHz is applied to measure the magnitude and phase responses of a fiber Bragg grating.

Automatic characteristic frequency association and all-sideband demodulation for the detection of a bearing fault

NASA Astrophysics Data System (ADS)

Firla, Marcin; Li, Zhong-Yang; Martin, Nadine; Pachaud, Christian; Barszcz, Tomasz

2016-12-01

This paper proposes advanced signal-processing techniques to improve condition monitoring of operating machines. The proposed methods use the results of a blind spectrum interpretation that includes harmonic and sideband series detection. The first contribution of this study is an algorithm for automatic association of harmonic and sideband series to characteristic fault frequencies according to a kinematic configuration. The approach proposed has the advantage of taking into account a possible slip of the rolling-element bearings. In the second part, we propose a full-band demodulation process from all sidebands that are relevant to the spectral estimation. To do so, a multi-rate filtering process in an iterative schema provides satisfying precision and stability over the targeted demodulation band, even for unsymmetrical and extremely narrow bands. After synchronous averaging, the filtered signal is demodulated for calculation of the amplitude and frequency modulation functions, and then any features that indicate faults. Finally, the proposed algorithms are validated on vibration signals measured on a test rig that was designed as part of the European Innovation Project 'KAStrion'. This rig simulates a wind turbine drive train at a smaller scale. The data show the robustness of the method for localizing and extracting a fault on the main bearing. The evolution of the proposed features is a good indicator of the fault severity.

Development of a Bone-Conducted Ultrasonic Hearing Aid for the Profoundly Deaf: Evaluation of Sound Quality Using a Semantic Differential Method

NASA Astrophysics Data System (ADS)

Nakagawa, Seiji; Fujiyuki, Chika; Kagomiya, Takayuki

2013-07-01

Bone-conducted ultrasound (BCU) is perceived even by the profoundly sensorineural deaf. A novel hearing aid using the perception of amplitude-modulated BCU (BCU hearing aid: BCUHA) has been developed. However, there is room for improvement particularly in terms of sound quality. BCU speech is accompanied by a strong high-pitched tone and contain some distortion. In this study, the sound quality of BCU speech with several types of amplitude modulation [double-sideband with transmitted carrier (DSB-TC), double-sideband with suppressed carrier (DSB-SC), and transposed modulations] and air-conducted (AC) speech was quantitatively evaluated using semantic differential and factor analysis. The results showed that all the types of BCU speech had higher metallic and lower esthetic factor scores than AC speech. On the other hand, transposed speech was closer than the other types of BCU speech to AC speech generally; the transposed speech showed a higher powerfulness factor score than the other types of BCU speech and a higher esthetic factor score than DSB-SC speech. These results provide useful information for further development of the BCUHA.

80GHz waveform generator by optical Fourier synthesis of four spectral sidebands (Conference Presentation)

NASA Astrophysics Data System (ADS)

Fatome, Julien; Hammani, Kamal; Kibler, Bertrand; Finot, Christophe

2016-04-01

Versatile and easy to implement methods to generate arbitrary optical waveforms at high repetition rates are of considerable interest with applications in optical communications, all-optical signal processing, instrumentation systems and microwave signal manipulation. While shaping sinusoidal, Gaussian or hyperbolic secant intensity profiles is commonly achieved by means of modulators or mode-locked lasers, other pulse profiles such as parabolic, triangular or flat-top shapes still remain challenging to synthesize. In this context, several strategies were already explored. First, the linear pulse shaping is a common method to carve an initial ultrashort pulse train into the desired shape. The line-by-line shaping of a coherent frequency comb made of tens of spectral components was also investigated to generate more complex structures whereas Fourier synthesis of a few discrete frequencies spectrum was exploited to efficiently generate high-fidelity ultrafast periodic intensity profiles. Besides linear shaping techniques, several nonlinear methods were implemented to benefit from the adiabatic evolution of the intensity pulse profile upon propagation in optical fibers. Other examples of efficient methods are based on the photonic generation involving specific Mach-Zehnder modulators, microwave photonic filters as well as frequency-to-time conversion. In this contribution, we theoretically and experimentally demonstrate a new approach enabling the synthesis of periodic high-repetition rate pulses with various intensity profiles ranging from parabola to triangular and flat-top pulses. More precisely by linear phase and amplitude shaping of only four spectral lines is it possible to reach the targeted temporal profile. Indeed, tailoring the input symmetric spectrum only requires the determination of two physical parameters: the phase difference between the inner and outer spectral sidebands and the ratio between the amplitude of these sidebands. Therefore, a systematic bidimensional analysis provides the optimum parameters and also highlights that switching between the different waveforms is achieved by simply changing the spectral phase between the inner and outer sidebands. We successfully validate this concept with the generation of high-fidelity ultrafast periodic waveforms at 40 GHz by shaping with a liquid cristal on insulator a four sideband comb resulting from a phase-modulated continuous wave. In order to reach higher repetition rates, we also describe a new scenario to obtain the required initial spectrum by taking advantage of the four-wave mixing process occurring in a highly nonlinear fiber. This approach is experimentally implemented at a repetition rate of 80-GHz by use of intensity and phase measurements that stress that full-duty cycle, high-quality, triangular, parabolic or flat-top profiles are obtained in full agreement with numerical simulations. The reconfigurable property of this photonic waveform generator is confirmed. Finally, the generation of bunch of shaped pulses is investigated, as well as the impact of Brillouin backscattering.

Generation of Optical Millimeter Wave Using Two Cascaded Polarization Modulators Based on Frequency Octupling Without Filtering

NASA Astrophysics Data System (ADS)

Yang, Yang; Ma, Jianxin; Zhang, Ruijiao; Xin, Xiangjun; Zhang, Junyi

2015-11-01

An approach to generate an optical millimeter wave is introduced with frequency octupling using two cascaded polarization modulators followed by polarizers, respectively. By adjusting the modulation indexes of polarization modulators, only the ±4th-order sidebands are generated with a pure spectrum. Since no filter is needed, the proposed technique can be used to generate a frequency-tunable millimeter wave with a large frequency-tunable range. To prove the feasibility of the proposed approach, a simulation is conducted to generate an 80-GHz millimeter wave, and then its transmission performance is checked.

Metrology Camera System Using Two-Color Interferometry

NASA Technical Reports Server (NTRS)

Dubovitsky, Serge; Liebe, Carl Christian; Peters, Robert; Lay, Oliver

2007-01-01

A metrology system that contains no moving parts simultaneously measures the bearings and ranges of multiple reflective targets in its vicinity, enabling determination of the three-dimensional (3D) positions of the targets with submillimeter accuracy. The system combines a direction-measuring metrology camera and an interferometric range-finding subsystem. Because the system is based partly on a prior instrument denoted the Modulation Sideband Technology for Absolute Ranging (MSTAR) sensor and because of its 3D capability, the system is denoted the MSTAR3D. Developed for use in measuring the shape (for the purpose of compensating for distortion) of large structures like radar antennas, it can also be used to measure positions of multiple targets in the course of conventional terrestrial surveying. A diagram of the system is shown in the figure. One of the targets is a reference target having a known, constant distance with respect to the system. The system comprises a laser for generating local and target beams at a carrier frequency; a frequency shifting unit to introduce a frequency shift offset between the target and local beams; a pair of high-speed modulators that apply modulation to the carrier frequency in the local and target beams to produce a series of modulation sidebands, the highspeed modulators having modulation frequencies of FL and FM; a target beam launcher that illuminates the targets with the target beam; optics and a multipixel photodetector; a local beam launcher that launches the local beam towards the multi-pixel photodetector; a mirror for projecting to the optics a portion of the target beam reflected from the targets, the optics being configured to focus the portion of the target beam at the multi-pixel photodetector; and a signal-processing unit connected to the photodetector. The portion of the target beam reflected from the targets produces spots on the multi-pixel photodetector corresponding to the targets, respectively, and the signal-processing unit centroids the spots to determine bearings of the targets, respectively. As the spots oscillate in intensity because they are mixed with the local laser beam that is flood illuminating the focal plane, the phase of oscillation of each spot is measured, the phase of sidebands in the oscillation of each spot being proportional to a distance to the corresponding target relative to the reference target A.

Caffeine increases sugar-sweetened beverage consumption in a free-living population: a randomised controlled trial.

PubMed

Keast, Russell S J; Swinburn, Boyd A; Sayompark, Dhoungsiri; Whitelock, Susie; Riddell, Lynn J

2015-01-28

Excessive sugar-sweetened beverage (SSB) consumption has been associated with overweight and obesity. Caffeine is a common additive to SSB, and through dependence effects, it has the potential to promote the consumption of caffeine-containing foods. The objective of the present study was to assess the influence that caffeine has on the consumption of SSB. Participants (n 99) were blindly assigned to either a caffeinated SSB (C-SSB) or a non-caffeinated SSB (NC-SSB) group. Following randomisation, all participants completed a 9 d flavour-conditioning paradigm. They then completed a 28 d ad libitum intake intervention where they consumed as much or as little of C-SSB or NC-SSB as desired. The amount consumed (ml) was recorded daily, 4 d diet diaries were collected and liking of SSB was assessed at the start and end of the intervention. Participants (n 50) consuming the C-SSB had a daily SSB intake of 419 (sd 298) ml (785 (sd 559) kJ/d) over the 28 d intervention, significantly more than participants (n 49) consuming the NC-SSB (273 (sd 278) ml/d, 512 (sd 521) kJ/d) (P=0.05). However, participants who consumed the C-SSB liked the SSB more than those who consumed the NC-SSB (6.3 v. 6.0 on a nine-point hedonic scale, P= 0.022). The addition of low concentrations of caffeine to the SSB significantly increases the consumption of the SSB. Regulating caffeine as a food additive may be an effective strategy to decrease the consumption of nutrient-poor high-energy foods and beverages.

Laser System for Precise, Unambiguous Range Measurements

NASA Technical Reports Server (NTRS)

Dubovitsky, Serge; Lay, Oliver

2005-01-01

The Modulation Sideband Technology for Absolute Range (MSTAR) architecture is the basis of design of a proposed laser-based heterodyne interferometer that could measure a range (distance) as great as 100 km with a precision and resolution of the order of 1 nm. Simple optical interferometers can measure changes in range with nanometer resolution, but cannot measure range itself because interference is subject to the well-known integer-multiple-of-2 -radians phase ambiguity, which amounts to a range ambiguity of the order of 1 m at typical laser wavelengths. Existing rangefinders have a resolution of the order of 10 m and are therefore unable to resolve the ambiguity. The proposed MSTAR architecture bridges the gap, enabling nanometer resolution with an ambiguity range that can be extended to arbitrarily large distances. The MSTAR architecture combines the principle of the heterodyne interferometer with the principle of extending the ambiguity range of an interferometer by using light of two wavelengths. The use of two wavelengths for this purpose is well established in optical metrology, radar, and sonar. However, unlike in traditional two-color laser interferometry, light of two wavelengths would not be generated by two lasers. Instead, multiple wavelengths would be generated as sidebands of phase modulation of the light from a single frequency- stabilized laser. The phase modulation would be effected by applying sinusoidal signals of suitable frequencies (typically tens of gigahertz) to high-speed electro-optical phase modulators. Intensity modulation can also be used

Engineering Design Handbook: Environmental Series. Part Three. Induced Environmental Factors

DTIC Science & Technology

1976-01-20

beams are combined on a photo- detector, a beat frequency at 25 MHz is produced. Periodic motion of the reflecting surface then modulates sidebands...about the 25-MHz beat frequency. The ampli- tude and frequency of the vibration are determined by demodulation of the phase-modulated 25-MHz signal...VibrationBulletin, No. 41, Part 6 (December 1970), pp. 29-34. 70. E. G Fischer, "Sine Beat Vibration Testing Related to Earthquake Response Spectra

Analysis and Synthesis of Pseudo-Periodic[InlineEquation not available: see fulltext.]-Like Noise by Means of Wavelets with Applications to Digital Audio

NASA Astrophysics Data System (ADS)

Polotti, Pietro; Evangelista, Gianpaolo

2001-12-01

Voiced musical sounds have nonzero energy in sidebands of the frequency partials. Our work is based on the assumption, often experimentally verified, that the energy distribution of the sidebands is shaped as powers of the inverse of the distance from the closest partial. The power spectrum of these pseudo-periodic processes is modeled by means of a superposition of modulated[InlineEquation not available: see fulltext.] components, that is, by a pseudo-periodic[InlineEquation not available: see fulltext.]-like process. Due to the fundamental selfsimilar character of the wavelet transform,[InlineEquation not available: see fulltext.] processes can be fruitfully analyzed and synthesized by means of wavelets. We obtain a set of very loosely correlated coefficients at each scale level that can be well approximated by white noise in the synthesis process. Our computational scheme is based on an orthogonal[InlineEquation not available: see fulltext.]-band filter bank and a dyadic wavelet transform per channel. The[InlineEquation not available: see fulltext.] channels are tuned to the left and right sidebands of the harmonics so that sidebands are mutually independent. The structure computes the expansion coefficients of a new orthogonal and complete set of harmonic-band wavelets. The main point of our scheme is that we need only two parameters per harmonic in order to model the stochastic fluctuations of sounds from a pure periodic behavior.

Contact acoustic nonlinearity (CAN)-based continuous monitoring of bolt loosening: Hybrid use of high-order harmonics and spectral sidebands

NASA Astrophysics Data System (ADS)

Zhang, Zhen; Liu, Menglong; Liao, Yaozhong; Su, Zhongqing; Xiao, Yi

2018-03-01

The significance of evaluating bolt tightness in engineering structures, preferably in a continuous manner, cannot be overemphasized. With hybrid use of high-order harmonics (HOH) and spectral sidebands, a contact acoustic nonlinearity (CAN)-based monitoring framework is developed for detecting bolt loosening and subsequently evaluating the residual torque on a loose bolt. Low-frequency pumping vibration is introduced into the bolted joint to produce a "breathing" effect at the joining interface that modulates the propagation characteristics of a high-frequency probing wave when it traverses the bolt, leading to the generation of HOH and vibro-acoustic nonlinear distortions (manifested as sidebands in the signal spectrum). To gain insight into the mechanism of CAN generation and to correlate the acquired nonlinear responses of a loose joint with the residual torque remaining on the bolt, an analytical model based on micro-contact theory is established. Two types of nonlinear index, respectively exploiting the induced HOH and spectral sidebands, are defined without dependence on excitation intensity and are experimentally demonstrated to be effective in continuously monitoring bolt loosening in both aluminum-aluminum and composite-composite bolted joints. Taking a step further, variation of the index pair is quantitatively associated with the residual torque on a loose bolt. The approach developed provides a reliable method of continuous evaluation of bolt tightness in both composite and metallic joints, regardless of their working conditions, from early awareness of bolt loosening at an embryonic stage to quantitative estimation of residual torque.

Characterization and compensation of the residual chirp in a Mach-Zehnder-type electro-optical intensity modulator.

PubMed

Rogers, C E; Carini, J L; Pechkis, J A; Gould, P L

2010-01-18

We utilize various techniques to characterize the residual phase modulation of a waveguide-based Mach-Zehnder electro-optical intensity modulator. A heterodyne technique is used to directly measure the phase change due to a given change in intensity, thereby determining the chirp parameter of the device. This chirp parameter is also measured by examining the ratio of sidebands for sinusoidal amplitude modulation. Finally, the frequency chirp caused by an intensity pulse on the nanosecond time scale is measured via the heterodyne signal. We show that this chirp can be largely compensated with a separate phase modulator. The various measurements of the chirp parameter are in reasonable agreement.

A novel OCS millimeter-wave generation scheme with data carried only by one sideband and wavelength reuse for uplink connection

NASA Astrophysics Data System (ADS)

Zhu, Zihang; Zhao, Shanghong; Yao, Zhoushi; Tan, Qinggui; Li, Yongjun; Chu, Xingchun; Shi, Lei; Hou, Rui

2012-11-01

We propose a novel optical carrier suppression (OCS) millimeter-wave generation scheme with data carried only by one sideband using a dual-drive Mach-Zehnder modulator (MZM) in radio-over-fiber system, and the transmission performance is also investigated. As the signal is transmitted along the fiber, there is no time shifting of the codes caused by chromatic dispersion. Simulation results show that the eye diagram keeps open and clear even when the optical millimeter-waves are transmitted over 110 km and the power penalty is about 1.9 dB after fiber transmission distance of 60 km. Furthermore, due to the +1 order sideband carrying no data, a full duplex radio-over-fiber link based on wavelength reuse is also built to simplify the base station. The bidirectional 2.5 Gbit/s data is successfully transmitted over a 40 km standard single mode fiber with less than 0.8 dB power penalty in the simulation. Both theoretical analysis and simulation results show that our scheme is feasible and we can obtain a simple cost-efficient configuration and good performance over long-distance transmission.

A simulation study of harmonics regeneration in noise reduction for electric and acoustic stimulation.

PubMed

Hu, Yi

2010-05-01

Recent research results show that combined electric and acoustic stimulation (EAS) significantly improves speech recognition in noise, and it is generally established that access to the improved F0 representation of target speech, along with the glimpse cues, provide the EAS benefits. Under noisy listening conditions, noise signals degrade these important cues by introducing undesired temporal-frequency components and corrupting harmonics structure. In this study, the potential of combining noise reduction and harmonics regeneration techniques was investigated to further improve speech intelligibility in noise by providing improved beneficial cues for EAS. Three hypotheses were tested: (1) noise reduction methods can improve speech intelligibility in noise for EAS; (2) harmonics regeneration after noise reduction can further improve speech intelligibility in noise for EAS; and (3) harmonics sideband constraints in frequency domain (or equivalently, amplitude modulation in temporal domain), even deterministic ones, can provide additional benefits. Test results demonstrate that combining noise reduction and harmonics regeneration can significantly improve speech recognition in noise for EAS, and it is also beneficial to preserve the harmonics sidebands under adverse listening conditions. This finding warrants further work into the development of algorithms that regenerate harmonics and the related sidebands for EAS processing under noisy conditions.

Frequency-agile, rapid scanning spectroscopy: absorption sensitivity of 2 × 10-12 cm-1 Hz-1/2 with a tunable diode laser

NASA Astrophysics Data System (ADS)

Long, D. A.; Truong, G.-W.; van Zee, R. D.; Plusquellic, D. F.; Hodges, J. T.

2014-03-01

We present ultrasensitive measurements of molecular absorption using frequency-agile rapid scanning, cavity ring-down spectroscopy with an external-cavity diode laser. A microwave source that drives an electro-optic phase modulator with a bandwidth of 20 GHz generates pairs of sidebands on the probe laser. The optical cavity provides for high sensitivity and filters the carrier and all but a single, selected sideband. Absorption spectra were acquired by stepping the tunable sideband from mode-to-mode of the ring-down cavity at a rate that was limited only by the cavity decay time. This approach allows for scanning rates of 8 kHz per cavity resonance, a minimum detectable absorption coefficient of 1.7 × 10-11 cm-1 after only 20 ms of averaging, and a noise-equivalent absorption coefficient of 1.7 × 10-12 cm-1 Hz-1/2. By comparison with cavity-enhanced laser absorption spectrometers reported in the literature, the present system is, to the best of our knowledge, among the most sensitive and has by far the highest spectrum scanning rate.

A Laser Stabilization System for Rydberg Atom Physics

DTIC Science & Technology

2015-09-06

offset locking method which we did. For each system, a small amount of light from a 852 nm (780 nm) diode laser is picked off from the output beam ...this way, tunable sidebands, from 1-10 GHz, that are themselves modulated at .05-5 MHz, can be generated on the input laser beam . The light from the...phase modulation signal. This signal is fed back into the fast (10 MHz bandwidth) locking electronics of the diode laser system to lock the laser to

Cross-phase-modulation-induced instability in photonic-crystal fibers.

PubMed

Serebryannikov, E E; Konorov, S O; Ivanov, A A; Alfimov, M V; Scalora, M; Zheltikov, A M

2005-08-01

Cross-phase-modulation-induced instability is identified as a significant mechanism for efficient parametric four-wave-mixing frequency conversion in photonic-crystal fibers. Fundamental-wavelength femtosecond pulses of a Cr, forsterite laser are used in our experiments to transform the spectrum of copropagating second-harmonic pulses of the same laser in a photonic-crystal fiber. Efficient generation of sidebands shifted by more than 80 THz with respect to the central frequency of the second harmonic is observed in the output spectrum of the probe field.

Electron emission perpendicular to the polarization direction in laser-assisted XUV atomic ionization

NASA Astrophysics Data System (ADS)

Gramajo, A. A.; Della Picca, R.; Arbó, D. G.

2017-08-01

We present a theoretical study of ionization of the hydrogen atom due to an XUV pulse in the presence of an infrared (IR) laser with both fields linearly polarized in the same direction. In particular, we study the energy distribution of photoelectrons emitted perpendicularly to the polarization direction. As we previously showed in Gramajo et al. [Phys. Rev. A 94, 053404 (2016), 10.1103/PhysRevA.94.053404] for parallel emission, by means of a very simple semiclassical model which considers electron trajectories born at different ionization times, the electron energy spectrum can be interpreted as the interplay of intra- and intercycle interferences. However, contrary to the case of parallel emission the intracycle interference pattern stems from the coherent superposition of four electron trajectories giving rise to (i) interference of electron trajectories born during the same half cycle (intra-half-cycle interference) and (ii) interference between electron trajectories born during the first half cycle with those born during the second half cycle (inter-half-cycle interference). The intercycle interference is responsible for the formation of the sidebands. We also show that the destructive inter-half-cycle interference for the absorption and emission of an even number of IR laser photons is responsible for the characteristic sidebands in the perpendicular direction separated by twice the IR photon energy. This contrasts with the emission along the polarization axis (all sideband orders are present) since intra-half-cycle interferences do not exist in that case. The intracycle interference pattern works as a modulation of the sidebands and, in the same way, it is modulated by the intra-half-cycle interference pattern. We analyze the dependence of the energy spectrum on the laser intensity and the time delay between the XUV pulse and the IR laser. Finally, we show that our semiclassical simulations are in very good agreement with quantum calculations within the strong-field approximation and the numerical solution of the time-dependent Schrödinger equation, giving rise to nonzero emission, in contraposition to other theories.

Ssb1 and Ssb2 cooperate to regulate mouse hematopoietic stem and progenitor cells by resolving replicative stress.

PubMed

Shi, Wei; Vu, Therese; Boucher, Didier; Biernacka, Anna; Nde, Jules; Pandita, Raj K; Straube, Jasmin; Boyle, Glen M; Al-Ejeh, Fares; Nag, Purba; Jeffery, Jessie; Harris, Janelle L; Bain, Amanda L; Grzelak, Marta; Skrzypczak, Magdalena; Mitra, Abhishek; Dojer, Norbert; Crosetto, Nicola; Cloonan, Nicole; Becherel, Olivier J; Finnie, John; Skaar, Jeffrey R; Walkley, Carl R; Pandita, Tej K; Rowicka, Maga; Ginalski, Krzysztof; Lane, Steven W; Khanna, Kum Kum

2017-05-04

Hematopoietic stem and progenitor cells (HSPCs) are vulnerable to endogenous damage and defects in DNA repair can limit their function. The 2 single-stranded DNA (ssDNA) binding proteins SSB1 and SSB2 are crucial regulators of the DNA damage response; however, their overlapping roles during normal physiology are incompletely understood. We generated mice in which both Ssb1 and Ssb2 were constitutively or conditionally deleted. Constitutive Ssb1/Ssb2 double knockout (DKO) caused early embryonic lethality, whereas conditional Ssb1/Ssb2 double knockout (cDKO) in adult mice resulted in acute lethality due to bone marrow failure and intestinal atrophy featuring stem and progenitor cell depletion, a phenotype unexpected from the previously reported single knockout models of Ssb1 or Ssb2 Mechanistically, cDKO HSPCs showed altered replication fork dynamics, massive accumulation of DNA damage, genome-wide double-strand breaks enriched at Ssb-binding regions and CpG islands, together with the accumulation of R -loops and cytosolic ssDNA. Transcriptional profiling of cDKO HSPCs revealed the activation of p53 and interferon (IFN) pathways, which enforced cell cycling in quiescent HSPCs, resulting in their apoptotic death. The rapid cell death phenotype was reproducible in in vitro cultured cDKO-hematopoietic stem cells, which were significantly rescued by nucleotide supplementation or after depletion of p53. Collectively, Ssb1 and Ssb2 control crucial aspects of HSPC function, including proliferation and survival in vivo by resolving replicative stress to maintain genomic stability. © 2017 by The American Society of Hematology.

Ssb1 and Ssb2 cooperate to regulate mouse hematopoietic stem and progenitor cells by resolving replicative stress

PubMed Central

Vu, Therese; Boucher, Didier; Biernacka, Anna; Nde, Jules; Pandita, Raj K.; Straube, Jasmin; Boyle, Glen M.; Al-Ejeh, Fares; Jeffery, Jessie; Harris, Janelle L.; Bain, Amanda L.; Grzelak, Marta; Skrzypczak, Magdalena; Mitra, Abhishek; Dojer, Norbert; Crosetto, Nicola; Cloonan, Nicole; Becherel, Olivier J.; Finnie, John; Skaar, Jeffrey R.; Walkley, Carl R.; Pandita, Tej K.; Rowicka, Maga; Ginalski, Krzysztof

2017-01-01

Hematopoietic stem and progenitor cells (HSPCs) are vulnerable to endogenous damage and defects in DNA repair can limit their function. The 2 single-stranded DNA (ssDNA) binding proteins SSB1 and SSB2 are crucial regulators of the DNA damage response; however, their overlapping roles during normal physiology are incompletely understood. We generated mice in which both Ssb1 and Ssb2 were constitutively or conditionally deleted. Constitutive Ssb1/Ssb2 double knockout (DKO) caused early embryonic lethality, whereas conditional Ssb1/Ssb2 double knockout (cDKO) in adult mice resulted in acute lethality due to bone marrow failure and intestinal atrophy featuring stem and progenitor cell depletion, a phenotype unexpected from the previously reported single knockout models of Ssb1 or Ssb2. Mechanistically, cDKO HSPCs showed altered replication fork dynamics, massive accumulation of DNA damage, genome-wide double-strand breaks enriched at Ssb-binding regions and CpG islands, together with the accumulation of R-loops and cytosolic ssDNA. Transcriptional profiling of cDKO HSPCs revealed the activation of p53 and interferon (IFN) pathways, which enforced cell cycling in quiescent HSPCs, resulting in their apoptotic death. The rapid cell death phenotype was reproducible in in vitro cultured cDKO-hematopoietic stem cells, which were significantly rescued by nucleotide supplementation or after depletion of p53. Collectively, Ssb1 and Ssb2 control crucial aspects of HSPC function, including proliferation and survival in vivo by resolving replicative stress to maintain genomic stability. PMID:28270450

Topological Quantum Information in a 3D Neutral Atom Array

DTIC Science & Technology

2015-01-02

being only weakly in the Lamb-Dicke Figure 1: Projection sideband cooling. The pink curves show the (from left to right) Δn=+1,0,-1 and-2 transitions...45 154012 (2012). 4. C. Knoernschild, T. Kim, P. Maunz, S. G. Crain, and J. Kim, “Stable optical phase modulation with micromirrors ,” Opt. Express

Foods and beverages associated with higher intake of sugar-sweetened beverages.

PubMed

Mathias, Kevin C; Slining, Meghan M; Popkin, Barry M

2013-04-01

Although consumption of sugar-sweetened beverages (SSBs) is associated with higher caloric intakes, the amount SSBs contribute to higher intakes has not been addressed. To estimate the amount SSBs contribute to higher caloric intakes and determine how the diets of SSB consumers and nonconsumers differ. The What We Eat In America, NHANES 2003-2010 surveys were combined into a sample of 13,421 children; analyses were conducted in December 2012. To determine the contribution of SSBs to higher caloric intakes, total non-SSB intake (food + non-SSB beverages) of SSB consumers and nonconsumers were compared using linear regression models controlling for demographic and socioeconomic factors. Analyses also compared intakes between nonconsumers and SSB consumers with different amounts of SSB consumption. For children aged 2-5 years and 6-11 years, total non-SSB intakes did not differ between nonconsumers and SSB consumers at any level of SSB consumption, indicating that SSBs were primarily responsible for the higher caloric intakes among SSB consumers. A similar finding was observed among children aged 12-18 years; however, both food and SSB contributed to higher caloric intakes of adolescents consuming ≥500 kcal of SSBs. Among those aged 12-18 years, higher intakes of foods (e.g., pizza, burgers, fried potatoes, and savory snacks) and lower intakes of non-SSB beverages (e.g., fluid milk and fruit juice) were associated with increased SSB intake. Sugar-sweetened beverages are primarily responsible for the higher caloric intakes of SSB consumers, and SSB consumption is associated with intake of a select number of food and beverage groups, some of which are often unhealthy (e.g., pizza and grain-based desserts). Copyright © 2013 American Journal of Preventive Medicine. Published by Elsevier Inc. All rights reserved.

Unmasking the anti-La/SSB response in sera from patients with Sjogren's syndrome by specific blocking of anti-idiotypic antibodies to La/SSB antigenic determinants.

PubMed

Routsias, John G; Touloupi, Evgenia; Dotsika, Eleni; Moulia, Avrilia; Tsikaris, Vassilios; Sakarellos, Constantinos; Sakarellos-Daitsiotis, Maria; Moutsopoulos, Haralampos M; Tzioufas, Athanasios G

2002-06-01

Autoantigen La/SSB is molecular target of humoral autoimmunity in patients with primary Sjogren's Syndrome (pSS) and systemic lupus erythematosus (SLE). In this study, we investigated the existence and possible influence of anti-idiotypic response to anti-La/SSB antibodies. Synthetic peptide analogs (pep) of the major antigenic determinants of La/SSB (289-308 aa and 349-364 aa) were prepared. Based on "molecular recognition" theory, complementary peptides (cpep), derived by anti-parallel readings of the noncoding strand of La/SSB DNA encoding for its antigenic determinants, were constructed. Sera from 150 patients with anti-La/SSB antibodies, 30 patients without anti-La/SSB antibodies, and 42 normal individuals were tested against all four peptides. F(ab')(2) fragments from anti-peptide IgG were prepared and F(ab')(2) - IgG interactions were evaluated using a specific anti-idiotypic ELISA. All four peptides were recognized by anti-La positive sera (83% and 51% for pep and cpep 349-364 and 51% and 28% for pep and cpep289-308, respectively). Anti-cpep F(ab')(2 )bound to a common idiotype (Id) located within or spatially close to the antigen combining site of anti La/SSB (anti-pep) antibodies. Homologous and cross-inhibition experiments further confirmed this relation. The anti-idiotypic antibodies inhibited the anti-La/SSB antibody binding to recombinant La/SSB by 91%. To overcome the anti-idiotypic interference in anti-La/SSB detection, a specific assay was developed. Sera were heated for dissociation of Id-anti-Id complexes, anti-Id antibodies blocked with cpep, and anti-La/SSB reactivity was recovered. Application of this method to anti-Ro positive-anti-La/SSB "negative" sera showed that all anti-Ro/SSA positive autoimmune sera also possess anti-La/SSB antibodies. This reaction was not observed in 14 anti-Ro negative- anti-Sm/RNP positive sera from patients with SLE. Autoimmune sera from patients with pSS and SLE contain anti-idiotypic antibodies targeting a common anti-La/SSB idiotype. These antibodies can be detected using complementary peptides of La/SSB epitopes. The antiidiotypic antibodies mask the anti-La/SSB response. Hidden anti-La/SSB antibodies can be released and detected using complementary epitope analogs.

The association between the availability of sugar-sweetened beverage in school vending machines and its consumption among adolescents in California: a propensity score matching approach.

PubMed

Shi, Lu

2010-01-01

There is controversy over to what degree banning sugar-sweetened beverage (SSB) sales at schools could decrease the SSB intake. This paper uses the adolescent sample of 2005 California Health Interview Survey to estimate the association between the availability of SSB from school vending machines and the amount of SSB consumption. Propensity score stratification and kernel-based propensity score matching are used to address the selection bias issue in cross-sectional data. Propensity score stratification shows that adolescents who had access to SSB through their school vending machines consumed 0.170 more drinks of SSB than those who did not (P < .05). Kernel-based propensity score matching shows the SSB consumption difference to be 0.158 on the prior day (P < .05). This paper strengthens the evidence for the association between SSB availability via school vending machines and the actual SSB consumption, while future studies are needed to explore changes in other beverages after SSB becomes less available.

Single molecule analysis of Thermus thermophilus SSB protein dynamics on single-stranded DNA.

PubMed

Zhang, Jichuan; Zhou, Ruobo; Inoue, Jin; Mikawa, Tsutomu; Ha, Taekjip

2014-04-01

Single-stranded (ss) DNA binding (SSB) proteins play central roles in DNA replication, recombination and repair in all organisms. We previously showed that Escherichia coli (Eco) SSB, a homotetrameric bacterial SSB, undergoes not only rapid ssDNA-binding mode transitions but also one-dimensional diffusion (or migration) while remaining bound to ssDNA. Whereas the majority of bacterial SSB family members function as homotetramers, dimeric SSB proteins were recently discovered in a distinct bacterial lineage of extremophiles, the Thermus-Deinococcus group. Here we show, using single-molecule fluorescence resonance energy transfer (FRET), that homodimeric bacterial SSB from Thermus thermophilus (Tth) is able to diffuse spontaneously along ssDNA over a wide range of salt concentrations (20-500 mM NaCl), and that TthSSB diffusion can help transiently melt the DNA hairpin structures. Furthermore, we show that two TthSSB molecules undergo transitions among different DNA-binding modes while remaining bound to ssDNA. Our results extend our previous observations on homotetrameric SSBs to homodimeric SSBs, indicating that the dynamic features may be shared among different types of SSB proteins. These dynamic features of SSBs may facilitate SSB redistribution and removal on/from ssDNA, and help recruit other SSB-interacting proteins onto ssDNA for subsequent DNA processing in DNA replication, recombination and repair.

A Mixed Methods Analysis of Beverage Choices in Adolescents and Their Parents Using the Theory of Planned Behavior

PubMed Central

Riebl, Shaun K; MacDougall, Carly; Hill, Catelyn; Estabrooks, Paul A; Dunsmore, Julie C; Savla, Jyoti; Frisard, Madlyn I; Dietrich, Andrea M; Davy, Brenda M

2015-01-01

Background Added sugar intake in the form of sugar-sweetened beverages (SSB) has been considered a contributor to weight gain and cardiometabolic dysfunction in adults and youth. Adolescents are some of the highest consumers of added sugars, taking in ~16% of their total calories from added sugars with ~40% of these calories coming from SSB. Youth’s food preferences and self-regulation of dietary intake can be influenced by parents. Objective To evaluate the Theory of Planned Behavior’s (TPB) effectiveness in understanding and predicting adolescents' SSB consumption, identify which constructs are the most important when evaluating SSB consumption in adolescents, and determine if and how adolescents' beverage choices are influenced by parents' reactions to their beverage choices. Design Measurements for this cross-sectional study included four record-assisted 24-hour dietary recalls and responses to a SSB-specific TPB questionnaire from 100 adolescents. Consenting parents completed a beverage intake questionnaire, a TPB questionnaire, and Parent Response to Beverage Choice Questionnaire. Results The TPB explained 34% of the variance in adolescents' and parents' intention to limit SSB to less than one cup per day. Parents' perceived behavioral control (b=1.35, p=0.002) and adolescents' subjective norms (b=0.57, p=0.001) were the strongest predictors of intention, and intention was the strongest predictor of SSB consumption in both adolescents and parents (b=−37, p=0.026, b=−49, p=0.003). The TPB explained more variance in parent SSB consumption (R2=0.38) than adolescents (R2=0.22). Parents did more discouraging of SSB and encouraging of non-SSB. Adolescents' intention to limit SSB moderated the relationship between parents' reactions encouraging SSB and adolescents' predicted SSB consumption (p=0.021). Conclusions The TPB explained a small, but significant amount of variance in adolescents' SSB consumption. When addressing adolescent SSB intake, people in addition to parents may influence their intentions and SSB consumption. PMID:26686818

The Essential Role of the Deinococcus radiodurans ssb Gene in Cell Survival and Radiation Tolerance

PubMed Central

Lockhart, J. Scott; DeVeaux, Linda C.

2013-01-01

Recent evidence has implicated single-stranded DNA-binding protein (SSB) expression level as an important factor in microbial radiation resistance. The genome of the extremely radiation resistant bacterium Deinococcus radiodurans contains genes for two SSB homologs: the homodimeric, canonical Ssb, encoded by the gene ssb, and a novel pentameric protein encoded by the gene ddrB. ddrB is highly induced upon exposure to radiation, and deletions result in decreased radiation-resistance, suggesting an integral role of the protein in the extreme resistance exhibited by this organism. Although expression of ssb is also induced after irradiation, Ssb is thought to be involved primarily in replication. In this study, we demonstrate that Ssb in D. radiodurans is essential for cell survival. The lethality of an ssb deletion cannot be complemented by providing ddrB in trans. In addition, the radiation-sensitive phenotype conferred by a ddrB deletion is not alleviated by providing ssb in trans. By altering expression of the ssb gene, we also show that lower levels of transcription are required for optimal growth than are necessary for high radiation resistance. When expression is reduced to that of E. coli, ionizing radiation resistance is similarly reduced. UV resistance is also decreased under low ssb transcript levels where growth is unimpaired. These results indicate that the expression of ssb is a key component of both normal cellular metabolism as well as pathways responsible for the high radiation tolerance of D. radiodurans. PMID:23951213

[Expression and purification of a novel thermophilic bacterial single-stranded DNA-binding protein and enhancement the synthesis of DNA and cDNA].

PubMed

Jia, Xiao-Wei; Zhang, Guo-Hui; Shi, Hai-Yan

2012-12-01

Express a novel species of single-stranded DNA-binding protein (SSB) derived from Thermococcus kodakarensis KOD1, abbreviated kod-ssb. And evaluate the effect of kod-ssb on PCR-based DNA amplification and reverse transcription. We express kod-ssb with the Transrtta (DE3), and kod-ssb was purified by affinity chromatography on a Ni2+ Sepharose column, detected by SDS-PAGE. To evaluate the effect of kod-ssb on PCR-based DNA amplification, the human beta globin gene was used as template to amplify a 5-kb, 9-kb and 13-kb. And to detect the effect of kod-ssb on reverse transcription, we used RNA from flu cell culture supernatant extraction as templates to implement qRT-PCR reaction. The plasmid pET11a-kod was transformed into Transetta (DE3) and the recombinant strain Transetta (pET11 a-kod) was obtained. The kod-ssb was highly expressed when the recombinant strain Transetta(pET11a-kod) was induced by IPTG. The specific protein was detected by SDS-PAGE. To confirm that kod-ssb can enhance target DNA synthesis and reduce PCR by-products, 5-, 9-, and 13-kb human beta globin gene fragments were used as templates for PCR. When PCR reactions did not include SSB proteins, the specific PCR product was contaminated with non-specific products. When kod -ssb was added, kod-ssb significantly enhanced amplification of the 5-, 9-and 13-kb target product and minimised the non-specific PCR products. To confirm that kod-ssb can enhance target cDNA synthesis, RNA from flu cell culture supernatant extraction was used as templates for qRT-PCR reaction. The results was that when kod-ssb was added, kod-ssb significantly enhanced the synthesis of cDNA, average Ct value is 19.42, and the average Ct value without kod-ssb is 22.15. kod-ssb may in future be used to enhance DNA and cDNA amplification.

Consumption of sugar-sweetened beverages and its association with overweight among young children from China.

PubMed

Yu, Pan; Chen, Yun; Zhao, Ai; Bai, Ying; Zheng, Yingdong; Zhao, Wenzhi; Zhang, Yumei

2016-09-01

To fully understand the sugar-sweetened beverage (SSB) consumption status among Chinese young children and to explore its association with weight gain. In this cross-sectional study, data on sociodemographic characteristics, SSB intake and weight/height were collected by means of face-to-face interviews. The intake of SSB among young Chinese children in relation to their age, different characteristics and types of SSB consumed is described, and the association between SSB intake and BMI-for-age Z-score and overweight is explored. Seven large cities and two villages in China. Nine hundred and forty-six healthy children, aged 3-7 years. The proportion of SSB intake among Chinese young children was 80·5 %; 3·4 % were daily consumers, 34·0 % (31·4 %) consumed at least once per week (month). The per capita and per consumer SSB intake was 63·1 9 (sd 100·8) and 78·4 (sd 106·9) ml/d. Children from rural areas consumed twice, or even triple, the amount of SSB as those from urban areas (P<0·001) and great disparities existed between the types of SSB consumed by urban and rural children. An association was found between increased SSB intake and higher BMI-for-age Z-score (P<0·05) after adjusting for potential confounders; there was also an association between SSB intake and increased risk of being overweight or obese. The consumption status of SSB in Chinese young children is of concern. There was a positive association between SSB intake and weight gain. Measures should be taken to improve the present situation of SSB consumption among Chinese young children.

The Association between the Availability of Sugar-Sweetened Beverage in School Vending Machines and Its Consumption among Adolescents in California: A Propensity Score Matching Approach

PubMed Central

Shi, Lu

2010-01-01

There is controversy over to what degree banning sugar-sweetened beverage (SSB) sales at schools could decrease the SSB intake. This paper uses the adolescent sample of 2005 California Health Interview Survey to estimate the association between the availability of SSB from school vending machines and the amount of SSB consumption. Propensity score stratification and kernel-based propensity score matching are used to address the selection bias issue in cross-sectional data. Propensity score stratification shows that adolescents who had access to SSB through their school vending machines consumed 0.170 more drinks of SSB than those who did not (P < .05). Kernel-based propensity score matching shows the SSB consumption difference to be 0.158 on the prior day (P < .05). This paper strengthens the evidence for the association between SSB availability via school vending machines and the actual SSB consumption, while future studies are needed to explore changes in other beverages after SSB becomes less available. PMID:20976298

Associations among sugar sweetened beverage intake, visceral fat, and cortisol awakening response in minority youth

PubMed Central

Shearrer, GE; Daniels, MJ; Toledo-Corral, CM; Weigensberg, MJ; Spruijt-Metz, D; Davis, JN

2016-01-01

Context Abdominal adiposity has long been associated with excess caloric intake possibly resulting from increased psychosocial stress and associated cortisol dysfunction. However, the relationship of sugar-sweetened beverage (SSB) intake specifically with cortisol variability and visceral adipose tissue (VAT) is unknown. Objective To examine the relationships between SSB intake, VAT, and cortisol response in minority youth. Design A cross-sectional analysis. Setting The University of Southern California. Participants 60 overweight/obese Non-Hispanic Black and Hispanic adolescents ages 14–18 years. Main Outcome Measures VAT via Magnet Resonance Imaging (MRI), cortisol awakening response (CAR) via multiple salivary samples, and SSB intake via multiple 24-hour diet recalls. SSB intake was divided into the following: low SSB consumers (< 1 servings per day), medium SSB consumers (≥1 - <2 servings per day), high SSB consumers (≥2 servings per day). Analysis of covariance were run with VAT and CAR as dependent variables and SSB intake categories (independent variable) with the following a priori covariates: sex, Tanner stage, ethnicity, caloric intake, and body mass index. Results The high SSB intake group exhibited a 7% higher VAT compared to the low SSB intake group (β=0.25, CI:(0.03, 0.33), p=0.02). CAR was associated with VAT (β=0.31, CI:(0.01,0.23), p=0.02). The high SSB intake group exhibited 22% higher CAR compared to the low SSB intake group (β=0.30, CI:(0.02,0.48), p=0.04). Conclusion This is the first study exploring the relationship between SSB, VAT, and CAR. SSB consumption appears to be independently associated greater abdominal adiposity and higher morning cortisol variability in overweight and obese minority youth. This study highlights potential targets for interventions specifically to reduce SSB intake in a minority youth population. PMID:27660033

DNA repair properties of Escherichia coli tif-1, recAo281 and lexA1 strains deficient in single-strand DNA binding protein.

PubMed

Whittier, R F; Chase, J W

1983-01-01

Mutations affecting single-strand DNA binding protein (SSB) impair induction of mutagenic (SOS) repair. To further investigate the role of SSB in SOS induction and DNA repair, isogenic strains were constructed combining the ssb+, ssb-1 or ssb-113 alleles with one or more mutations known to alter regulation of damage inducible functions. As is true in ssb+ strains tif-1 (recA441) was found to allow thermal induction of prophage lambda + and Weigle reactivation in ssb-1 and ssb-113 strains. Furthermore, tif-1 decreased the UV sensitivity of the ssb-113 strain slightly and permitted UV induction of prophage lambda + at 30 degrees C. Strains carrying the recAo281 allele were also constructed. This mutation causes high constitutive levels of RecA protein synthesis and relieves much of the UV sensitivity conferred by lexA- alleles without restoring SOS (error-prone) repair. In contrast, the recAo281 allele failed to alleviate the UV sensitivity associated with either ssb- mutation. In a lexA1 recAo281 background the ssb-1 mutation increased the extent of postirradiation DNA degradation and concommitantly increased UV sensitivity 20-fold to the level exhibited by a recA1 strain. The ssb-113 mutation also increased UV sensitivity markedly in this background but did so without greatly increasing postirradiation DNA degradation. These results suggest a direct role for SSB in recombinational repair apart from and in addition to its role in facilitating induction of the recA-lexA regulon.

Absolute Distance Measurement with the MSTAR Sensor

NASA Technical Reports Server (NTRS)

Lay, Oliver P.; Dubovitsky, Serge; Peters, Robert; Burger, Johan; Ahn, Seh-Won; Steier, William H.; Fetterman, Harrold R.; Chang, Yian

2003-01-01

The MSTAR sensor (Modulation Sideband Technology for Absolute Ranging) is a new system for measuring absolute distance, capable of resolving the integer cycle ambiguity of standard interferometers, and making it possible to measure distance with sub-nanometer accuracy. The sensor uses a single laser in conjunction with fast phase modulators and low frequency detectors. We describe the design of the system - the principle of operation, the metrology source, beamlaunching optics, and signal processing - and show results for target distances up to 1 meter. We then demonstrate how the system can be scaled to kilometer-scale distances.

Full-duplex radio-over-fiber system with tunable millimeter-wave signal generation and wavelength reuse for upstream signal.

PubMed

Wang, Yiqun; Pei, Li; Li, Jing; Li, Yueqin

2017-06-10

A full-duplex radio-over-fiber system is proposed, which provides both the generation of a millimeter-wave (mm-wave) signal with tunable frequency multiplication factors (FMFs) and wavelength reuse for uplink data. A dual-driving Mach-Zehnder modulator and a phase modulator are cascaded to form an optical frequency comb. An acousto-optic tunable filter based on a uniform fiber Bragg grating (FBG-AOTF) is employed to select three target optical sidebands. Two symmetrical sidebands are chosen to generate mm waves with tunable FMFs up to 16, which can be adjusted by changing the frequency of the applied acoustic wave. The optical carrier is reused at the base station for uplink connection. FBG-AOTFs driven by two acoustic wave signals are experimentally fabricated and further applied in the proposed scheme. Results of the research indicate that the 2-Gbit/s data can be successfully transmitted over a 25-km single-mode fiber for bidirectional full-duplex channels with power penalty of less than 2.6 dB. The feasibility of the proposed scheme is verified by detailed simulations and partial experiments.

Subcarrier multiplexing with dispersion reduction and direct detection

DOEpatents

Sargis, Paul D.; Haigh, Ronald E.; McCammon, Kent G.

1997-01-01

An SCM system for simultaneously reducing the concomitant problems of receiver complexity and dispersion penalty and without requiring the use of an expensive, high-bandwidth optical detector. The system provides both a dispersion reduction and a direct detection to the receiver, with microwave mixers and lithium niobate external modulators that produce sidebands that are only separated by a few gigahertz from a principal laser optical carrier. Digital data streams are independently impressed upon these sidebands for transmission over an ordinary single-mode fiber. Independent high-speed data streams are upconverted to microwave frequencies. These subcarriers are then combined with a microwave power combiner and amplified with a microwave amplifier. A solid-state 1550-nm laser carrier is modulated by the microwave subcarriers. An erbium-doped fiber amplifier (EDFA) is used just prior to long-distance transmission over ordinary single-mode fiber. The transmitted optical signal may then traverse multiple EDFAs to compensate for long-haul optical fiber losses prior to detection. At a receiving end, the optical signal is split into multiple paths. The subcarrier channels are optically pre-selected using a narrowband optical filter, such as a fiber Fabry-Perot (FFP) filter. An optical detector converts the selected optical signal into a baseband electrical data stream.

Interaction with Single-stranded DNA-binding Protein Stimulates Escherichia coli Ribonuclease HI Enzymatic Activity*

PubMed Central

Petzold, Christine; Marceau, Aimee H.; Miller, Katherine H.; Marqusee, Susan; Keck, James L.

2015-01-01

Single-stranded (ss) DNA-binding proteins (SSBs) bind and protect ssDNA intermediates formed during replication, recombination, and repair reactions. SSBs also directly interact with many different genome maintenance proteins to stimulate their enzymatic activities and/or mediate their proper cellular localization. We have identified an interaction formed between Escherichia coli SSB and ribonuclease HI (RNase HI), an enzyme that hydrolyzes RNA in RNA/DNA hybrids. The RNase HI·SSB complex forms by RNase HI binding the intrinsically disordered C terminus of SSB (SSB-Ct), a mode of interaction that is shared among all SSB interaction partners examined to date. Residues that comprise the SSB-Ct binding site are conserved among bacterial RNase HI enzymes, suggesting that RNase HI·SSB complexes are present in many bacterial species and that retaining the interaction is important for its cellular function. A steady-state kinetic analysis shows that interaction with SSB stimulates RNase HI activity by lowering the reaction Km. SSB or RNase HI protein variants that disrupt complex formation nullify this effect. Collectively our findings identify a direct RNase HI/SSB interaction that could play a role in targeting RNase HI activity to RNA/DNA hybrid substrates within the genome. PMID:25903123

Optical vector network analysis of ultranarrow transitions in 166Er3+ : 7LiYF4 crystal.

PubMed

Kukharchyk, N; Sholokhov, D; Morozov, O; Korableva, S L; Cole, J H; Kalachev, A A; Bushev, P A

2018-02-15

We present optical vector network analysis (OVNA) of an isotopically purified Er166 3+ :LiYF 4 7 crystal. The OVNA method is based on generation and detection of a modulated optical sideband by using a radio-frequency vector network analyzer. This technique is widely used in the field of microwave photonics for the characterization of optical responses of optical devices such as filters and high-Q resonators. However, dense solid-state atomic ensembles induce a large phase shift on one of the optical sidebands that results in the appearance of extra features on the measured transmission response. We present a simple theoretical model that accurately describes the observed spectra and helps to reconstruct the absorption profile of a solid-state atomic ensemble as well as corresponding change of the refractive index in the vicinity of atomic resonances.

Spectra of 42S1/2→32D5/2 Transitions of a Single Trapped 40Ca+ Ion

NASA Astrophysics Data System (ADS)

Gong, Shi-Jie; Zhou, Fei; Wu, Hao-Yu; Wan, Wei; Chen, Liang; Feng, Mang

2015-01-01

We investigate the spectra of the electric quadrupole 42S1/2→32D5/2 transitions in a single 40Ca+ ion confined in a home-built linear trap. We probe the transitions with an ultra-narrow bandwidth laser at 729 nm. In a weak magnetic field, the quadrupole transition splits into ten components with the maximal line strength proportional to their squared Clebsch—Gordan factors. In a magnetic field of the order of Gauss, the observed equidistant sideband reflects the Zeeman substructure modulated by the quantized oscillation due to the secular motion in the trap. The temperature of the trapped ion can be determined by the envelope of the sideband spectrum. We also demonstrate the Rabi oscillation in a carrier transition after the ion has been Doppler cooled, which can be fitted by the model with the thermal state of motion.

Molecular mechanism of DNA association with single-stranded DNA binding protein

PubMed Central

Maffeo, Christopher

2017-01-01

Abstract During DNA replication, the single-stranded DNA binding protein (SSB) wraps single-stranded DNA (ssDNA) with high affinity to protect it from degradation and prevent secondary structure formation. Although SSB binds ssDNA tightly, it can be repositioned along ssDNA to follow the advancement of the replication fork. Using all-atom molecular dynamics simulations, we characterized the molecular mechanism of ssDNA association with SSB. Placed in solution, ssDNA–SSB assemblies were observed to change their structure spontaneously; such structural changes were suppressed in the crystallographic environment. Repeat simulations of the SSB–ssDNA complex under mechanical tension revealed a multitude of possible pathways for ssDNA to come off SSB punctuated by prolonged arrests at reproducible sites at the SSB surface. Ensemble simulations of spontaneous association of short ssDNA fragments with SSB detailed a three-dimensional map of local affinity to DNA; the equilibrium amount of ssDNA bound to SSB was found to depend on the electrolyte concentration but not on the presence of the acidic tips of the SSB tails. Spontaneous formation of ssDNA bulges and their diffusive motion along SSB surface was directly observed in multiple 10-µs-long simulations. Such reptation-like motion was confined by DNA binding to high-affinity spots, suggesting a two-step mechanism for SSB diffusion. PMID:29059392

The school environment and sugar-sweetened beverage consumption among Guatemalan adolescents.

PubMed

Godin, Katelyn M; Chacón, Violeta; Barnoya, Joaquin; Leatherdale, Scott T

2017-11-01

The current study sought to examine Guatemalan adolescents' consumption of sugar-sweetened beverages (SSB), identify which individual-level characteristics are associated with SSB consumption and describe school characteristics that may influence students' SSB consumption. Within this observational pilot study, a questionnaire was used to assess students' consumption of three varieties of SSB (soft drinks, energy drinks, sweetened coffees/teas), as well as a variety of sociodemographic and behavioural characteristics. We collected built environment data to examine aspects of the school food environment. We developed Poisson regression models for each SSB variety and used descriptive analyses to characterize the sample. Guatemala City, Guatemala. Guatemalan adolescents (n 1042) from four (two public, two private) secondary schools. Built environment data revealed that students from the two public schools lacked access to water fountains/coolers. The SSB industry had a presence in the schools through advertisements, sponsored food kiosks and products available for sale. Common correlates of SSB consumption included school type, sedentary behaviour, frequency of purchasing lunch in the cafeteria, and frequency of purchasing snacks from vending machines in school and off school property. Guatemalan adolescents frequently consume SSB, which may be encouraged by aspects of the school environment. Schools represent a viable setting for equitable population health interventions designed to reduce SSB consumption, including increasing access to clean drinking-water, reducing access to SSB, restricting SSB marketing and greater enforcement of existing food policies.

A Review of the Literature on Policies Directed at the Youth Consumption of Sugar Sweetened Beverages123

PubMed Central

Levy, David T.; Friend, Karen B.; Wang, Y. Claire

2011-01-01

Sugar sweetened beverages (SSB) constitute a large percentage of energy consumed by youth. This paper reviews the literature on school nutrition policies and price interventions directed at youth SSB consumption. In addition to considering the direct effect of policies on SSB consumption, we provide an overview of the literature on how SSB consumption affects total energy intake (TEI) and BMI, as well as on how TEI affects BMI. By considering each of these links, we attempted to gauge the effect of policies directed at SSB consumption, as well as highlight areas that merit future research. We found that school nutrition and price policies reduce SSB consumption and that reduced SSB consumption is associated with a reduction in energy intake that can influence BMI. Policies directed at SSB consumption can play an important role in reducing youth overweight and obesity. PMID:22332051

A core hSSB1–INTS complex participates in the DNA damage response

PubMed Central

Zhang, Feng; Ma, Teng; Yu, Xiaochun

2013-01-01

Summary Human single-stranded DNA-binding protein 1 (hSSB1) plays an important role in the DNA damage response and the maintenance of genomic stability. It has been shown that the core hSSB1 complex contains hSSB1, INTS3 and C9orf80. Using protein affinity purification, we have identified integrator complex subunit 6 (INTS6) as a major subunit of the core hSSB1 complex. INTS6 forms a stable complex with INTS3 and hSSB1 both in vitro and in vivo. In this complex, INTS6 directly interacts with INTS3. In response to the DNA damage response, along with INTS3 and hSSB1, INTS6 relocates to the DNA damage sites. Moreover, the hSSB1–INTS complex regulates the accumulation of RAD51 and BRCA1 at DNA damage sites and the correlated homologous recombination. PMID:23986477

SSB as an organizer/mobilizer of genome maintenance complexes

PubMed Central

Shereda, Robert D.; Kozlov, Alexander G.; Lohman, Timothy M.; Cox, Michael M.; Keck, James L.

2008-01-01

When duplex DNA is altered in almost any way (replicated, recombined, or repaired), single strands of DNA are usually intermediates, and single-stranded DNA binding (SSB) proteins are present. These proteins have often been described as inert, protective DNA coatings. Continuing research is demonstrating a far more complex role of SSB that includes the organization and/or mobilization of all aspects of DNA metabolism. Escherichia coli SSB is now known to interact with at least 14 other proteins that include key components of the elaborate systems involved in every aspect of DNA metabolism. Most, if not all, of these interactions are mediated by the amphipathic C-terminus of SSB. In this review, we summarize the extent of the eubacterial SSB interaction network, describe the energetics of interactions with SSB, and highlight the roles of SSB in the process of recombination. Similar themes to those highlighted in this review are evident in all biological systems. PMID:18937104

The impact of a local sugar sweetened beverage health promotion and price increase on sales in public leisure centre facilities.

PubMed

Breeze, Penny; Womack, Robert; Pryce, Robert; Brennan, Alan; Goyder, Elizabeth

2018-01-01

We aimed to evaluate the impact of a local sugar sweetened beverages (SSB) health promotion and 20p price increase in leisure centre venues and estimate the impact on consumption. Monthly cold drinks sales data and attendance at leisure centres across the city of Sheffield were analysed over the period January 2015-July 2017. Interrupted time-series methods were employed to estimate changes in consumption per attendance of SSB and non-SSB cold drinks following the introduction of the SSB policy from August 2016 adjusting for seasonal variation and autocorrelation. SSB price elasticities were estimated with fixed effects log-log models by SSB product type (soda can, soda bottle, soda post mix, energy drinks, juice from concentrate). We estimated a 31% (95% CI 4%, 59%) reduction in units of SSB sold per attendance in the year since the policy was introduced. We did not observe substitution effects to fruit juice or water but found sales of other artificially sweetened non-SSB products increased by 27% (95% CI 6%, 47%) after the introduction of the tax. Price elasticity analysis identified that a 1% increase in price alongside health promotion leads to a 3.8% (95% CI 3.1% 4.4%) decrease in demand for SSB's. Price elasticity of demand was highest for child friendly and high caffeine energy drinks. Demand for SSB drinks at leisure centre venues is highly responsive to the policy, particularly for child-friendly and high caffeine energy drinks, compared with other SSB tax policy evaluations. The policy also increased purchases of carbonated non-SSB.

On-chip microwave signal generation based on a silicon microring modulator.

PubMed

Shao, Haifeng; Yu, Hui; Li, Xia; Li, Yan; Jiang, Jianfei; Wei, Huan; Wang, Gencheng; Dai, Tingge; Chen, Qimei; Yang, Jianyi; Jiang, Xiaoqing

2015-07-15

A photonic-assisted microwave signal generator based on a silicon microring modulator is demonstrated. The microring cavity incorporates an embedded PN junction that enables a microwave signal to modulate the lightwave circling inside. The DC component of the modulated light is trapped in the cavity, while the high-order sideband components are able to exit the cavity and then generate microwave signals at new frequencies in a photodetector. In our proof-of-concept experiment, a 10 GHz microwave signal is converted to a 20 GHz signal in the optical domain with an electrical harmonic suppression ratio of 22 dB. An analytic model is also established to explain the operation mechanism, which agrees well with the measured data.

The physical basis for absorption of light. [effects on wave functions of gas molecules and atoms

NASA Technical Reports Server (NTRS)

Pickett, H. M.

1979-01-01

The effects of light absorption on the wave functions of gas-phase molecules and atoms are investigated by high resolution spectral measurements of radiation emerging from a sample. A Stark-modulated sample of methyl fluoride was irradiated at the 102 GHz rotational transition and the emergent radiation was resolved by means of a spectrum analyzer. For signal oscillator frequencies below or above the molecular resonance by one modulation frequency, the amplitudes of the upper and lower modulation sidebands are found to be of nonuniform intensity, which is inconsistent with amplitude modulation. Emission due to polarization is, however, calculated to be consistent with the results observed, indicating that light absorption should be considered as a subtractive stimulated emission.

Development and Evaluation of the Sugar-Sweetened Beverages Media Literacy (SSB-ML) Scale and Its Relationship With SSB Consumption

PubMed Central

Chen, Yvonnes; Porter, Kathleen J.; Estabrooks, Paul A.; Zoellner, Jamie

2017-01-01

Understanding how adults’ media literacy skill sets impact their sugar-sweetened beverage (SSB) intake provides insight into designing effective interventions to enhance their critical analysis of marketing messages and thus improve their healthy beverage choices. However, a media literacy scale focusing on SSBs is lacking. This cross-sectional study uses baseline data from a large randomized controlled trial to (a) describe the psychometric properties of an SSB Media Literacy Scale (SSB-ML) scale and its subdomains, (b) examine how the scale varies across demographic variables, and (c) explain the scale’s concurrent validity to predict SSB consumption. Results from 293 adults in rural southwestern Virginia (81.6% female, 94.0% White, 54.1% receiving SNAP and/or WIC benefits, average 410 SSB kcal daily) show that overall SSB-ML scale and its subdomains have strong internal consistencies (Cronbach’s alphas ranging from 0.65 to 0.83). The Representation & Reality domain significantly predicted SSB kilocalories, after controlling for demographic variables. This study has implications for the assessment and inclusion of context-specific media literacy skills in behavioral interventions. PMID:27690635

Development and Evaluation of the Sugar-Sweetened Beverages Media Literacy (SSB-ML) Scale and Its Relationship With SSB Consumption.

PubMed

Chen, Yvonnes; Porter, Kathleen J; Estabrooks, Paul A; Zoellner, Jamie

2017-10-01

Understanding how adults' media literacy skill sets impact their sugar-sweetened beverage (SSB) intake provides insight into designing effective interventions to enhance their critical analysis of marketing messages and thus improve their healthy beverage choices. However, a media literacy scale focusing on SSBs is lacking. This cross-sectional study uses baseline data from a large randomized controlled trial to (a) describe the psychometric properties of an SSB Media Literacy Scale (SSB-ML) scale and its subdomains, (b) examine how the scale varies across demographic variables, and (c) explain the scale's concurrent validity to predict SSB consumption. Results from 293 adults in rural southwestern Virginia (81.6% female, 94.0% White, 54.1% receiving SNAP and/or WIC benefits, average 410 SSB kcal daily) show that overall SSB-ML scale and its subdomains have strong internal consistencies (Cronbach's alphas ranging from 0.65 to 0.83). The Representation & Reality domain significantly predicted SSB kilocalories, after controlling for demographic variables. This study has implications for the assessment and inclusion of context-specific media literacy skills in behavioral interventions.

Interaction with Single-stranded DNA-binding Protein Stimulates Escherichia coli Ribonuclease HI Enzymatic Activity

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

Petzold, Christine; Marceau, Aimee H.; Miller, Katherine H.

Single-stranded (ss) DNA-binding proteins (SSBs) bind and protect ssDNA intermediates formed during replication, recombination, and repair reactions. SSBs also directly interact with many different genome maintenance proteins to stimulate their enzymatic activities and/or mediate their proper cellular localization. We have identified an interaction formed between Escherichia coli SSB and ribonuclease HI (RNase HI), an enzyme that hydrolyzes RNA in RNA/DNA hybrids. The RNase HI·SSB complex forms by RNase HI binding the intrinsically disordered C terminus of SSB (SSB-Ct), a mode of interaction that is shared among all SSB interaction partners examined to date. Residues that comprise the SSB-Ct binding sitemore » are conserved among bacterial RNase HI enzymes, suggesting that RNase HI·SSB complexes are present in many bacterial species and that retaining the interaction is important for its cellular function. A steady-state kinetic analysis shows that interaction with SSB stimulates RNase HI activity by lowering the reaction Km. SSB or RNase HI protein variants that disrupt complex formation nullify this effect. Collectively our findings identify a direct RNase HI/SSB interaction that could play a role in targeting RNase HI activity to RNA/DNA hybrid substrates within the genome.« less

Interaction with Single-stranded DNA-binding Protein Stimulates Escherichia coli Ribonuclease HI Enzymatic Activity.

PubMed

Petzold, Christine; Marceau, Aimee H; Miller, Katherine H; Marqusee, Susan; Keck, James L

2015-06-05

Single-stranded (ss) DNA-binding proteins (SSBs) bind and protect ssDNA intermediates formed during replication, recombination, and repair reactions. SSBs also directly interact with many different genome maintenance proteins to stimulate their enzymatic activities and/or mediate their proper cellular localization. We have identified an interaction formed between Escherichia coli SSB and ribonuclease HI (RNase HI), an enzyme that hydrolyzes RNA in RNA/DNA hybrids. The RNase HI·SSB complex forms by RNase HI binding the intrinsically disordered C terminus of SSB (SSB-Ct), a mode of interaction that is shared among all SSB interaction partners examined to date. Residues that comprise the SSB-Ct binding site are conserved among bacterial RNase HI enzymes, suggesting that RNase HI·SSB complexes are present in many bacterial species and that retaining the interaction is important for its cellular function. A steady-state kinetic analysis shows that interaction with SSB stimulates RNase HI activity by lowering the reaction Km. SSB or RNase HI protein variants that disrupt complex formation nullify this effect. Collectively our findings identify a direct RNase HI/SSB interaction that could play a role in targeting RNase HI activity to RNA/DNA hybrid substrates within the genome. © 2015 by The American Society for Biochemistry and Molecular Biology, Inc.

The Rice Transcription Factor WRKY53 Suppresses Herbivore-Induced Defenses by Acting as a Negative Feedback Modulator of Mitogen-Activated Protein Kinase Activity1

PubMed Central

Hu, Lingfei; Ye, Meng; Zhang, Tongfang; Zhou, Guoxin; Wang, Qi; Lu, Jing

2015-01-01

The mechanisms by which herbivore-attacked plants activate their defenses are well studied. By contrast, little is known about the regulatory mechanisms that allow them to control their defensive investment and avoid a defensive overshoot. We characterized a rice (Oryza sativa) WRKY gene, OsWRKY53, whose expression is rapidly induced upon wounding and induced in a delayed fashion upon attack by the striped stem borer (SSB) Chilo suppressalis. The transcript levels of OsWRKY53 are independent of endogenous jasmonic acid but positively regulated by the mitogen-activated protein kinases OsMPK3/OsMPK6. OsWRKY53 physically interacts with OsMPK3/OsMPK6 and suppresses their activity in vitro. By consequence, it modulates the expression of defensive, MPK-regulated WRKYs and thereby reduces jasmonic acid, jasmonoyl-isoleucine, and ethylene induction. This phytohormonal reconfiguration is associated with a reduction in trypsin protease inhibitor activity and improved SSB performance. OsWRKY53 is also shown to be a negative regulator of plant growth. Taken together, these results show that OsWRKY53 functions as a negative feedback modulator of MPK3/MPK6 and thereby acts as an early suppressor of induced defenses. OsWRKY53 therefore enables rice plants to control the magnitude of their defensive investment during early signaling. PMID:26453434

FM Tactical Communications under Intentional Interference.

DTIC Science & Technology

1975-06-06

FUEN WIIHOUT JAt4i.,IV(i*) If. YGU WISH 1*i EXECU1&. ANtHI IiG ~E s PUA7 naIn --- a- l--f*-~ * igure 15. Sample Computer Runs,(aUnsu1.table Coma.o Link...AM and SSB Modulation,* IRE Transaction on Military Electronics, NIL-5t (January 1961), p. do 6. J. Rose Heverly, Range, Mobility and Transmis’slon

Early introduction and cumulative consumption of sugar-sweetened beverages during the pre-school period and risk of obesity at 8-14 years of age.

PubMed

Cantoral, A; Téllez-Rojo, M M; Ettinger, A S; Hu, H; Hernández-Ávila, M; Peterson, K

2016-02-01

Consumption of sugar-sweetened beverages (SSB) has been associated with risk of obesity, but little evidence exists to evaluate if age of introduction and cumulative SSB consumption increases risk in children. The objective of the study was to estimate the relationship between age of introduction and cumulative SSB consumption with risk of obesity in 227 Mexican children. SSB intake was measured every 6 months; age of introduction and cumulative consumption during the pre-school period were calculated. Height, weight, waist circumference, SSB intake and other relevant variables were measured at age 8-14 years and obesity defined using standard criteria. All participants were introduced to SSB before age 24 months and most (73%) before 12 months. Early SSB introduction (≤12 months) was not significantly associated with increased odds of obesity (odds ratio [OR] = 2.00, 95% confidence interval [CI]: 0.87, 4.59). However, children in the highest tertile of cumulative SSB consumption, compared with the lowest, had almost three times the odds of general (OR = 2.99, 95% CI: 1.27, 7.00) and abdominal (OR = 2.70, 95% CI: 1.03, 7.03) obesity at age 8-14 years. High SSB consumption increased the likelihood of obesity in 8-14-year-old children. Our results suggest that SSB intake should be delayed and excessive SSB consumption in pre-school period should be avoided. © 2015 World Obesity.

Sugar sweetened beverage consumption by Australian children: Implications for public health strategy

PubMed Central

2011-01-01

Background High consumption of sugar sweetened beverages (SSBs) has been linked to unhealthy weight gain and nutrition related chronic disease. Intake of SSB among children remains high in spite of public health efforts to reduce consumption, including restrictions on marketing to children and limitations on the sale of these products in many schools. Much extant literature on Australian SSB consumption is out-dated and lacks information on several key issues. We sought to address this using a contemporary Australian dataset to examine purchase source, consumption pattern, dietary factors, and demographic profile of SSB consumption in children. Methods Data were from the 2007 Australian National Children's Nutrition and Physical Activity Survey, a representative random sample of 4,834 Australian children aged 2-16 years. Mean SSB intake by type, location and source was calculated and logistic regression models were fitted to determine factors associated with different levels of consumption. Results SSB consumption was high and age-associated differences in patterns of consumption were evident. Over 77% of SSB consumed was purchased via supermarkets and 60% of all SSB was consumed in the home environment. Less than 17% of SSB was sourced from school canteens and fast food establishments. Children whose parents had lower levels of education consumed more SSB on average, while children whose parents had higher education levels were more likely to favour sweetened juices and flavoured milks. Conclusions SSB intake by Australian children remains high and warrants continued public health attention. Evidence based and age-targeted interventions, which also recognise supermarkets as the primary source of SSB, are recommended to reduce SSB consumption among children. Additionally, education of parents and children regarding the health consequences of high consumption of both carbonated and non-carbonated SSBs is required. PMID:22192774

Sugar sweetened beverage consumption by Australian children: implications for public health strategy.

PubMed

Hafekost, Katherine; Mitrou, Francis; Lawrence, David; Zubrick, Stephen R

2011-12-22

High consumption of sugar sweetened beverages (SSBs) has been linked to unhealthy weight gain and nutrition related chronic disease. Intake of SSB among children remains high in spite of public health efforts to reduce consumption, including restrictions on marketing to children and limitations on the sale of these products in many schools. Much extant literature on Australian SSB consumption is out-dated and lacks information on several key issues. We sought to address this using a contemporary Australian dataset to examine purchase source, consumption pattern, dietary factors, and demographic profile of SSB consumption in children. Data were from the 2007 Australian National Children's Nutrition and Physical Activity Survey, a representative random sample of 4,834 Australian children aged 2-16 years. Mean SSB intake by type, location and source was calculated and logistic regression models were fitted to determine factors associated with different levels of consumption. SSB consumption was high and age-associated differences in patterns of consumption were evident. Over 77% of SSB consumed was purchased via supermarkets and 60% of all SSB was consumed in the home environment. Less than 17% of SSB was sourced from school canteens and fast food establishments. Children whose parents had lower levels of education consumed more SSB on average, while children whose parents had higher education levels were more likely to favour sweetened juices and flavoured milks. SSB intake by Australian children remains high and warrants continued public health attention. Evidence based and age-targeted interventions, which also recognise supermarkets as the primary source of SSB, are recommended to reduce SSB consumption among children. Additionally, education of parents and children regarding the health consequences of high consumption of both carbonated and non-carbonated SSBs is required.

The impact of a tax on sugar-sweetened beverages according to socio-economic position: a systematic review of the evidence.

PubMed

Backholer, Kathryn; Sarink, Danja; Beauchamp, Alison; Keating, Catherine; Loh, Venurs; Ball, Kylie; Martin, Jane; Peeters, Anna

2016-12-01

A tax on sugar-sweetened beverages (SSB) has been proposed to address population weight gain but the effect across socio-economic position (SEP) is unclear. The current study aimed to clarify the differential impact(s) of SSB taxes on beverage purchases and consumption, weight outcomes and the amount paid in SSB taxes according to SEP. Databases (OVID and EMBASE) and grey literature were systematically searched in June 2015 to identify studies that examined effects of an SSB price increase on beverage purchases or consumption, weight outcomes or the amount paid in tax across SEP, within high-income countries. Of the eleven included articles, three study types were identified: (i) those that examined the association between variation in SSB taxes and SSB consumption and/or body weight (n 3); (ii) price elasticity estimation of SSB demand (n 1); and (iii) modelling of hypothetical SSB taxes by combining price elasticity estimates with population SEP-specific beverage consumption, energy intake or body weight (n 7). Few studies statistically tested differences in outcomes between SEP groups. Nevertheless, of the seven studies that reported on changes in weight outcomes for the total population following an increase in SSB price, all reported either similar reductions in weight across SEP groups or greater reductions for lower compared with higher SEP groups. All studies that examined the average household amount paid in tax (n 5) reported that an SSB tax would be regressive, but with small differences between higher- and lower-income households (0·10-1·0 % and 0·03 %-0·60 % of annual household income paid in SSB tax for low- and high-income households, respectively). Based on the available evidence, a tax on SSB will deliver similar population weight benefits across socio-economic strata or greater benefits for lower SEP groups. An SSB tax is shown to be consistently financially regressive, but to a small degree.

A Case Study of the Philadelphia Sugar-Sweetened Beverage Tax Policymaking Process: Implications for Policy Development and Advocacy.

PubMed

Purtle, Jonathan; Langellier, Brent; Lê-Scherban, Félice

Policymakers are increasingly proposing sugar-sweetened beverage (SSB) taxes as an evidence-based strategy to reduce chronic disease risk; and local health departments (LHDs) are well-positioned to play a role in SSB policy development and advocacy. However, most SSB tax proposals fail to become law and limited empiric guidance exists to inform advocacy efforts. In June 2016, Philadelphia, Pennsylvania, passed an SSB tax. To identify features of the Philadelphia SSB tax policymaking process that contributed to the proposal's passage. Qualitative case study. Semistructured interviews were conducted with key informants closely involved with the policymaking process. Interviews were audio-recorded and transcribed. Local news media about the SSB tax proposal were analyzed to triangulate interview findings. Analysis was conducted in NVivo 10 using inductive qualitative content analysis. Philadelphia, Pennsylvania, during the SSB tax policymaking in process. Nine key informants (2 city councilpersons, 4 city agency officials, 1 community-based advocate, 1 news reporter, and 1 researcher). The Philadelphia SSB tax proposal was introduced with the explicit goal of financing universal prekindergarten and deliberately not framed as a health intervention. This framing shifted contentious debates about government involvement in individual behavior toward discussions about how to finance universal prekindergarten, a goal for which broad support existed. The LHD played an important role in communicating research evidence about potential health benefits of the SSB tax proposal at the end of the policymaking process. During local SSB tax policy development processes, LHD officials and other advocates should encourage policymakers to design SSB tax policies so that revenue is directed toward community investments for which broad public support exists. When communicating with policymakers and the public, LHDs should consider emphasizing how SSB tax revenue will be used in addition to presenting evidence about the potential health benefits of the SSB tax at the local level.

Young adults' responses to alternative messages describing a sugar-sweetened beverage price increase.

PubMed

Gollust, Sarah E; Tang, Xuyang; White, James M; French, Simone A; Runge, Carlisle Ford; Rothman, Alexander J

2017-01-01

Many jurisdictions in the USA and globally are considering raising the prices of sugar-sweetened beverages (SSB) through taxes as a strategy to reduce their consumption. The objective of the present study was to identify whether the rationale provided for an SSB price increase affects young adults' behavioural intentions and attitudes towards SSB. Participants were randomly assigned to receive one of eight SSB price increase rationales. Intentions to purchase SSB and attitudes about the product and policy were measured. A forty-six-item cross-sectional Internet survey. Undergraduate students (n 494) at a large US Midwestern university. Rationale type was significantly associated with differences in participants' purchasing intentions for the full sample (F 7,485=2·53, P=0·014). Presenting the rationale for an SSB price increase as a user fee, an effort to reduce obesity, a strategy to offset health-care costs or to protect children led to lower SSB purchasing intentions compared with a message with no rationale. Rationale type was also significantly associated with differences in perceptions of soda companies (F 7,485=2·10, P=0·043); among low consumers of SSB, messages describing the price increase as a user fee or tax led to more negative perceptions of soda companies. The rationale attached to an SSB price increase could influence consumers. However, these message effects may depend on individuals' level of SSB consumption.

Exploring perceptions of the Mexican sugar-sweetened beverage tax among adolescents in north-west Mexico: a qualitative study.

PubMed

Ortega-Avila, Ana G; Papadaki, Angeliki; Jago, Russell

2018-02-01

To explore awareness and perceptions of the sugar-sweetened beverage (SSB) tax implemented in Mexico in 2014 among a sample of Mexican adolescents, and to investigate how the tax has affected their purchases and intake of SSB. Qualitative. Semi-structured interviews were conducted in April-May 2016. The data were analysed using thematic analysis. Adolescents residing in north-west Mexico (n 29, 55·2 % females), aged 15-19 years. Four main themes emerged: awareness of taxation; perceptions of how the tax has affected SSB intake; reasons why the tax was not perceived to have affected SSB intake; and preferences for substitution of the taxed SSB. Participants were mostly unaware of the tax and perceived that it would not cause reductions in their intake of SSB; they felt that the price increase was low and insufficient to affect intake. Taste preferences and 'addiction' to SSB were highlighted as the main reasons why participants perceived taxation would not affect intake. If SSB prices were to increase further via a higher tax, participants would consider substituting SSB with other beverages, namely home-made drinks (e.g. 100 % fruit juices), non-caloric, instant-flavoured drinks and water. These findings provide important insights into the views of this sample of Mexican adolescents regarding the taxation of SSB, by pointing out several possible limitations of the tax policy in Mexico. These results could inform the design of future interventions directed at Mexican youth that would complement and strengthen the current SSB taxation.

Silicon technology compatible photonic molecules for compact optical signal processing

NASA Astrophysics Data System (ADS)

Barea, Luis A. M.; Vallini, Felipe; Jarschel, Paulo F.; Frateschi, Newton C.

2013-11-01

Photonic molecules (PMs) based on multiple inner coupled microring resonators allow to surpass the fundamental constraint between the total quality factor (QT), free spectral range (FSR), and resonator size. In this work, we use a PM that presents doublets and triplets resonance splitting, all with high QT. We demonstrate the use of the doublet splitting for 34.2 GHz signal extraction by filtering the sidebands of a modulated optical signal. We also demonstrate that very compact optical modulators operating 2.75 times beyond its resonator linewidth limit may be obtained using the PM triplet splitting, with separation of ˜55 GHz.

Joint CPT and N resonance in compact atomic time standards

NASA Astrophysics Data System (ADS)

Crescimanno, Michael; Hohensee, Michael; Xiao, Yanhong; Phillips, David; Walsworth, Ron

2008-05-01

Currently development efforts towards small, low power atomic time standards use current-modulated VCSELs to generate phase-coherent optical sidebands that interrogate the hyperfine structure of alkali atoms such as rubidium. We describe and use a modified four-level quantum optics model to study the optimal operating regime of the joint CPT- and N-resonance clock. Resonant and non-resonant light shifts as well as modulation comb detuning effects play a key role in determining the optimal operating point of such clocks. We further show that our model is in good agreement with experimental tests performed using Rb-87 vapor cells.

The MRIS feasibility study

NASA Technical Reports Server (NTRS)

Neece, Robert T.; Cross, Aubrey E.; Schrader, James H.

1993-01-01

The Microwave Reflectometer Ionization Sensor (MRIS) is an instrument being developed for use in detecting and ranging of electron density layers in the reentry plasma of a space transfer vehicle. The rationale for the selection of the Double Sideband Suppressed Carrier (DSBSC) system used in the feasibility study for the MRIS is presented. A 25 GHz single-oscillator system and a 220 GHz double-oscillator system are described. The 25 GHz system was constructed and tested in the laboratory and test results are presented. As developed, the system employs a sideband spacing of 160 MHz. Based on an estimated electromagnetic wave velocity in the plasma, a round-trip phase shift measurement accuracy of +/- 7.6 degrees was required for the desired +/- 1/2 cm distance measurement accuracy. The interaction of parallel ground and reflecting planes produces interference that prevents the basic DSBSC system from meeting the accuracy goal so a frequency modulation was added to the system to allow averaging of the measured phase deviation. With an FM deviation of +/- 1 GHz, laboratory measurements were made for distances from 5 to 61 cm tip free space. Accounting for the plasma velocity factor, 82 percent of the data were equal to or better than the desired accuracy. Based on this measured result a sideband spacing to 250 MHz could be expected to yield data approximately 96 percent within the accuracy goal.

Structure functions in decomposing Au-Pt systems

NASA Astrophysics Data System (ADS)

Glas, R.; Blaschko, O.; Rosta, L.

1992-09-01

The evolution of Au-Pt alloys quenched within the miscibility gap is investigated by small-angle neutron-scattering techniques. Moreover, in the vicinity of fundamental Bragg reflections the evolution of ``sideband'' satellites induced by a lattice-parameter modulation connected with the precipitation pattern is investigated by diffuse scattering methods. Structure functions are evaluated for a series of concentrations within the miscibility gap and compared to recent results of the literature.

Photonic Materials and Devices for RF (mmW) Sensing and Imaging

DTIC Science & Technology

2012-12-31

wave encoding thereby eliminating the need for bulky LO distribution cables. Also, optical processing techniques can be utilized to provide simple... optical powers, can be close to unity and low -noise photodetectors make the detection of exceedingly low power millimeter-waves practical. In... optically -filtering the modulated signal to pass only a single sideband and detecting the resultant optical signal with a low -noise photodetector we have

FM Quieting Curves and Related Topics

DTIC Science & Technology

1977-08-01

Electronics Engineering Group (EEO) is organized as an independent group reorting, directly to -the Comwiander, Air ’Force Conmmunica-r tions Service (WOC...NUMBER N/A 7. AklTHO -() 6. CONTRACT OR GRANT NUMBER(#) /, .C...or.e M./ Kizer/ , ,/A 9. PERFORMING ORGANIZATION NAME AND ADDRESS 10. PROGRAM ELEMENT...in vestigial sideband modulation) and are separated from the carrier frequency by a frequency difference equal to the frequency of the baseband

Interactions between Genetics and Sugar-Sweetened Beverage Consumption on Health Outcomes: A Review of Gene–Diet Interaction Studies

PubMed Central

Haslam, Danielle E.; McKeown, Nicola M.; Herman, Mark A.; Lichtenstein, Alice H.; Dashti, Hassan S.

2018-01-01

The consumption of sugar-sweetened beverages (SSB), which includes soft drinks, fruit drinks, and other energy drinks, is associated with excess energy intake and increased risk for chronic metabolic disease among children and adults. Thus, reducing SSB consumption is an important strategy to prevent the onset of chronic diseases, and achieve and maintain a healthy body weight. The mechanisms by which excessive SSB consumption may contribute to complex chronic diseases may partially depend on an individual’s genetic predisposition. Gene–SSB interaction investigations, either limited to single genetic loci or including multiple genetic variants, aim to use genomic information to define mechanistic pathways linking added sugar consumption from SSBs to those complex diseases. The purpose of this review is to summarize the available gene-SSB interaction studies investigating the relationships between genetics, SSB consumption, and various health outcomes. Current evidence suggests there are genetic predispositions for an association between SSB intake and adiposity; evidence for a genetic predisposition between SSB and type 2 diabetes or cardiovascular disease is limited. PMID:29375475

The magnetic tides of Honolulu

USGS Publications Warehouse

Love, Jeffrey J.; Rigler, Erin Joshua

2013-01-01

We review the phenomenon of time-stationary, periodic quiet-time geomagnetic tides. These are generated by the ionospheric and oceanic dynamos, and, to a lesser-extent, by the quiet-time magnetosphere, and they are affected by currents induced in the Earth's electrically conducting interior. We examine historical time series of hourly magnetic-vector measurements made at the Honolulu observatory. We construct high-resolution, frequency-domain Lomb-periodogram and maximum-entropy power spectra that reveal a panorama of stationary harmonics across periods from 0.1 to 10000.0-d, including harmonics that result from amplitude and phase modulation. We identify solar-diurnal tides and their annual and solar-cycle sideband modulations, lunar semi-diurnal tides and their solar-diurnal sidebands, and tides due to precession of lunar eccentricity and nodes. We provide evidence that a method intended for separating the ionospheric and oceanic dynamo signals by midnight subsampling of observatory data time series is prone to frequency-domain aliasing. The tidal signals we summarize in this review can be used to test our fundamental understanding of the dynamics of the quiet-time ionosphere and magnetosphere, induction in the ocean and in the electrically conducting interior of the Earth, and they are useful for defining a quiet-time baseline against which magnetospheric-storm intensity is measured.

Filterless frequency 12-tupling optical millimeter-wave generation using two cascaded dual-parallel Mach-Zehnder modulators.

PubMed

Zhu, Zihang; Zhao, Shanghong; Zheng, Wanze; Wang, Wei; Lin, Baoqin

2015-11-10

A novel frequency 12-tupling optical millimeter-wave (mm-wave) generation using two cascaded dual-parallel Mach-Zehnder modulators (DP-MZMs) without an optical filter is proposed and demonstrated by computer simulation. By properly adjusting the amplitude and phase of radio frequency (RF) driving signal and the direct current (DC) bias points of two DP-MZMs, a 120 GHz mm-wave with an optical sideband suppression ratio (OSSR) of 25.1 dB and a radio frequency spurious suppression ratio (RFSSR) of 19.1 dB is shown to be generated from a 10 GHz RF driving signal, which largely reduces the response frequency of electronic devices. Furthermore, it is also proved to be valid that even if the phase difference of RF driving signals, the RF driving voltage, and the DC bias voltage deviate from the ideal values to a certain degree, the performance is still acceptable. Since no optical filter is employed to suppress the undesired optical sidebands, a high-spectral-purity mm-wave signal tunable from 48 to 216 GHz can be obtained theoretically when a RF driving signal from 4 to 18 GHz is applied to the DP-MZMs, and the system can be readily implemented in wavelength-division-multiplexing upconversion systems to provide high-quality optical local oscillator signal.

General solution of undersampling frequency conversion and its optimization for parallel photodisplacement imaging.

PubMed

Nakata, Toshihiko; Ninomiya, Takanori

2006-10-10

A general solution of undersampling frequency conversion and its optimization for parallel photodisplacement imaging is presented. Phase-modulated heterodyne interference light generated by a linear region of periodic displacement is captured by a charge-coupled device image sensor, in which the interference light is sampled at a sampling rate lower than the Nyquist frequency. The frequencies of the components of the light, such as the sideband and carrier (which include photodisplacement and topography information, respectively), are downconverted and sampled simultaneously based on the integration and sampling effects of the sensor. A general solution of frequency and amplitude in this downconversion is derived by Fourier analysis of the sampling procedure. The optimal frequency condition for the heterodyne beat signal, modulation signal, and sensor gate pulse is derived such that undesirable components are eliminated and each information component is converted into an orthogonal function, allowing each to be discretely reproduced from the Fourier coefficients. The optimal frequency parameters that maximize the sideband-to-carrier amplitude ratio are determined, theoretically demonstrating its high selectivity over 80 dB. Preliminary experiments demonstrate that this technique is capable of simultaneous imaging of reflectivity, topography, and photodisplacement for the detection of subsurface lattice defects at a speed corresponding to an acquisition time of only 0.26 s per 256 x 256 pixel area.

A novel optical millimeter-wave signal generation approach to overcome chromatic dispersion

NASA Astrophysics Data System (ADS)

Liang, Dong; Jiang, Wei; Tan, Qinggui; Zhu, Zhongbo; Liu, Feng

2014-06-01

In this paper, a novel frequency octupling approach for optical millimeter-wave signal generation to overcome chromatic dispersion is proposed and demonstrated. The frequency octupling mm-wave with the baseband signal carried only by -4th order sideband is generated by properly adjusting a series of parameters, which are the modulation constant, the gain of baseband signal, the direct current bias and the different phase of the modulation arms. As the optical millimeter-wave signal is transmitted along the fiber, there is no time shift caused by chromatic dispersion. Theoretical analyses and simulated results show that when the optical mm-wave carrying 2.5 Gbps baseband signal transmits a distance of over 110 km, the eye diagram still keeps open and clear. The power penalty is about 0.4 dB after the optical signal transmits over 40 km. In additions, given the +4th order sideband carries no data, a full-duplex RoF link based on wavelength reuse is built for the uplink. The bidirectional 2.5 Gbps baseband signal could successfully transmit over 40 km with about 0.8 dB power penalty in the simulation. Both theoretical analyses and simulation results show that the full-duplex RoF link has good performance.

Subcarrier multiplexing with dispersion reduction and direct detection

DOEpatents

Sargis, P.D.; Haigh, R.E.; McCammon, K.G.

1997-01-21

An SCM system is disclosed for simultaneously reducing the concomitant problems of receiver complexity and dispersion penalty and without requiring the use of an expensive, high-bandwidth optical detector. The system provides both a dispersion reduction and a direct detection to the receiver, with microwave mixers and lithium niobate external modulators that produce sidebands that are only separated by a few gigahertz from a principal laser optical carrier. Digital data streams are independently impressed upon these sidebands for transmission over an ordinary single-mode fiber. Independent high-speed data streams are upconverted to microwave frequencies. These subcarriers are then combined with a microwave power combiner and amplified with a microwave amplifier. A solid-state 1550-nm laser carrier is modulated by the microwave subcarriers. An erbium-doped fiber amplifier (EDFA) is used just prior to long-distance transmission over ordinary single-mode fiber. The transmitted optical signal may then traverse multiple EDFAs to compensate for long-haul optical fiber losses prior to detection. At a receiving end, the optical signal is split into multiple paths. The subcarrier channels are optically pre-selected using a narrowband optical filter, such as a fiber Fabry-Perot (FFP) filter. An optical detector converts the selected optical signal into a baseband electrical data stream. 2 figs.

A study on the co- and adjacent channel protection requirements for mobile satellite ACSSB modulation

NASA Technical Reports Server (NTRS)

Sydor, John T.

1988-01-01

Samples of speech modulated by narrowband frequency modulation (NBFM) (cellular) and amplitude companded single sideband (ACSSB) radios were subjected to simulated co- and adjacent channel interference environments typical of proposed frequency division multiple access (FDMA) mobile satellite systems. These samples were then listened to by a group of evaluators whose subjective responses to the samples were used to produce a series of graphs showing the relationship between subjective acceptability, carrier to noise density (C/No), carrier to interference ratio (C/I), and frequency offset. The results show that in a mobile satellite environment, ACSSB deteriorates more slowly than NBFM. The co- and adjacent channel protection ratios for both modulation techniques were roughly the same, even though the mechanism for signal deterioration is different.

Modulator for tone and binary signals. [phase of modulation of tone and binary signals on carrier waves in communication systems

NASA Technical Reports Server (NTRS)

Mcchesney, J. R.; Lerner, T.; Fitch, E. J. (Inventor)

1975-01-01

Tones and binary information are transmitted as phase variations on a carrier wave of constant amplitude and frequency. The carrier and tones are applied to a balanced modulator for deriving an output signal including a pair of sidebands relative to the carrier. The carrier is phase modulated by a digital signal so that it is + or - 90 deg out of phase with the predetermined phase of the carrier. The carrier is combined in an algebraic summing device with the phase modulated signal and the balanced modulator output signal. The output of the algebraic summing device is hard limited to derive a constant amplitude and frequency signal having very narrow bandwidth requirements. At a receiver, the tones and binary data are detected with a phase locked loop having a voltage controlled oscillator driving a pair of orthogonal detection channels.

The impact of a local sugar sweetened beverage health promotion and price increase on sales in public leisure centre facilities

PubMed Central

Womack, Robert; Pryce, Robert; Brennan, Alan; Goyder, Elizabeth

2018-01-01

Background We aimed to evaluate the impact of a local sugar sweetened beverages (SSB) health promotion and 20p price increase in leisure centre venues and estimate the impact on consumption. Method Monthly cold drinks sales data and attendance at leisure centres across the city of Sheffield were analysed over the period January 2015-July 2017. Interrupted time-series methods were employed to estimate changes in consumption per attendance of SSB and non-SSB cold drinks following the introduction of the SSB policy from August 2016 adjusting for seasonal variation and autocorrelation. SSB price elasticities were estimated with fixed effects log-log models by SSB product type (soda can, soda bottle, soda post mix, energy drinks, juice from concentrate). Findings We estimated a 31% (95% CI 4%, 59%) reduction in units of SSB sold per attendance in the year since the policy was introduced. We did not observe substitution effects to fruit juice or water but found sales of other artificially sweetened non-SSB products increased by 27% (95% CI 6%, 47%) after the introduction of the tax. Price elasticity analysis identified that a 1% increase in price alongside health promotion leads to a 3.8% (95% CI 3.1% 4.4%) decrease in demand for SSB’s. Price elasticity of demand was highest for child friendly and high caffeine energy drinks. Interpretation Demand for SSB drinks at leisure centre venues is highly responsive to the policy, particularly for child-friendly and high caffeine energy drinks, compared with other SSB tax policy evaluations. The policy also increased purchases of carbonated non-SSB. PMID:29847553

Theory of controlling band-width broadening in terahertz sideband generation in semiconductors by a direct current electric field

NASA Astrophysics Data System (ADS)

Liu, Houquan; Zhang, Xingchu

2017-03-01

In a semiconductor, optically excited electron-hole pairs, driven by a strong terahertz (THz) field, can recombine to create THz sidebands in the optical spectrum. The sideband spectrum exhibits a "plateau" up to a cutoff frequency of 3.17Up, where Up is the ponderomotive energy. In this letter, we predict that the bandwidth of this sideband spectrum plateau can be broadened by applying an additional direct-current (DC) electric field. We find that if applying a DC field of EDC=0.2ETHz (where EDC and ETHz are the amplitudes of the DC field and THz field, respectively), the sideband spectrum presents three plateaus with 5.8Up, 10.05Up and 16Up being the cutoff frequencies of the first, second and third plateaus, respectively. This bandwidth broadening occurs because the DC field can increase the kinetic energy that an electron-hole pair can gain from the THz field. This effect means that the bandwidth of the sideband spectrum can be controlled flexibly by changing the DC field, thereby facilitating the ultrafast electro-optical applications of THz sideband generation.

SEPIA - a new single pixel receiver at the APEX telescope

NASA Astrophysics Data System (ADS)

Belitsky, V.; Lapkin, I.; Fredrixon, M.; Meledin, D.; Sundin, E.; Billade, B.; Ferm, S.-E.; Pavolotsky, A.; Rashid, H.; Strandberg, M.; Desmaris, V.; Ermakov, A.; Krause, S.; Olberg, M.; Aghdam, P.; Shafiee, S.; Bergman, P.; Beck, E. De; Olofsson, H.; Conway, J.; Breuck, C. De; Immer, K.; Yagoubov, P.; Montenegro-Montes, F. M.; Torstensson, K.; Pérez-Beaupuits, J.-P.; Klein, T.; Boland, W.; Baryshev, A. M.; Hesper, R.; Barkhof, J.; Adema, J.; Bekema, M. E.; Koops, A.

2018-04-01

Context. We describe the new Swedish-ESO PI Instrument for APEX (SEPIA) receiver, which was designed and built by the Group for Advanced Receiver Development (GARD), at Onsala Space Observatory (OSO) in collaboration with ESO. It was installed and commissioned at the APEX telescope during 2015 with an ALMA Band 5 receiver channel and updated with a new frequency channel (ALMA Band 9) in February 2016. Aim. This manuscript aims to provide, for observers who use the SEPIA receiver, a reference in terms of the hardware description, optics and performance as well as the commissioning results. Methods: Out of three available receiver cartridge positions in SEPIA, the two current frequency channels, corresponding to ALMA Band 5, the RF band 158-211 GHz, and Band 9, the RF band 600-722 GHz, provide state-of-the-art dual polarization receivers. The Band 5 frequency channel uses 2SB SIS mixers with an average SSB noise temperature around 45 K with IF (intermediate frequency) band 4-8 GHz for each sideband providing total 4 × 4 GHz IF band. The Band 9 frequency channel uses DSB SIS mixers with a noise temperature of 75-125 K with IF band 4-12 GHz for each polarization. Results: Both current SEPIA receiver channels are available to all APEX observers.

Tuning time-frequency methods for the detection of metered HF speech

NASA Astrophysics Data System (ADS)

Nelson, Douglas J.; Smith, Lawrence H.

2002-12-01

Speech is metered if the stresses occur at a nearly regular rate. Metered speech is common in poetry, and it can occur naturally in speech, if the speaker is spelling a word or reciting words or numbers from a list. In radio communications, the CQ request, call sign and other codes are frequently metered. In tactical communications and air traffic control, location, heading and identification codes may be metered. Moreover metering may be expected to survive even in HF communications, which are corrupted by noise, interference and mistuning. For this environment, speech recognition and conventional machine-based methods are not effective. We describe Time-Frequency methods which have been adapted successfully to the problem of mitigation of HF signal conditions and detection of metered speech. These methods are based on modeled time and frequency correlation properties of nearly harmonic functions. We derive these properties and demonstrate a performance gain over conventional correlation and spectral methods. Finally, in addressing the problem of HF single sideband (SSB) communications, the problems of carrier mistuning, interfering signals, such as manual Morse, and fast automatic gain control (AGC) must be addressed. We demonstrate simple methods which may be used to blindly mitigate mistuning and narrowband interference, and effectively invert the fast automatic gain function.

Low-noise and wideband hot-electron superconductive mixer for terahertz frequencies

NASA Astrophysics Data System (ADS)

Karasik, Boris S.; Skalare, Anders; McGrath, William R.; Bumble, Bruce; Leduc, Henry G.; Barner, J. B.; Kleinsasser, Alan W.; Burke, P. J.; Schoelkopf, Robert J.; Prober, Daniel E.

1998-11-01

Superconductive hot-electron bolometer (HEB) mixers have been built and tested in the frequency range from 1.1 THz to 2.5 THz. The mixer device is a 0.15 - 0.3 micrometer microbridge made from a 10 nm thick Nb film. This device employs diffusion as a cooling mechanism for hot electrons. The double sideband noise temperature was measured to be less than or equal to 3000 K at 2.5 THz and the mixer IF bandwidth is expected to be at least 10 GHz for a 0.1 micrometer long device. The local oscillator (LO) power dissipated in the HEB microbridge was 20 - 100 nW. Further improvement of the mixer characteristics can be potentially achieved by using Al microbridges. The advantages and parameters of such devices are evaluated. The HEB mixer is a primary candidate for ground based, airborne and spaceborne heterodyne instruments at THz frequencies. HEB receivers are planned for use on the NASA Stratospheric Observatory for Infrared Astronomy (SOFIA) and the ESA Far Infrared and Submillimeter Space Telescope (FIRST). The prospects of a submicron-size YBa2Cu3O7-(delta ) (YBCO) HEB are discussed. The expected LO power of 1 - 10 (mu) W and SSB noise temperature of approximately equals 2000 K may make this mixer attractive for various remote sensing applications.

Optical sideband generation up to room temperature with mid-infrared quantum cascade lasers.

PubMed

Houver, S; Cavalié, P; St-Jean, M Renaudat; Amanti, M I; Sirtori, C; Li, L H; Davies, A G; Linfield, E H; Pereira, T A S; Lebreton, A; Tignon, J; Dhillon, S S

2015-02-23

Mid-infrared (MIR) sideband generation on a near infrared (NIR) optical carrier is demonstrated within a quantum cascade laser (QCL). By employing an externally injected NIR beam, E(NIR), that is resonant with the interband transitions of the quantum wells in the QCL, the nonlinear susceptibility is enhanced, leading to both frequency mixing and sideband generation. A GaAs-based MIR QCL (E(QCL) = 135 meV) with an aluminum-reinforced waveguide was utilized to overlap the NIR and MIR modes with the optical nonlinearity of the active region. The resulting difference sideband (E(NIR) - E(QCL)) shows a resonant behavior as a function of NIR pump wavelength and a maximum second order nonlinear susceptibility, χ((2)), of ~1 nm/V was obtained. Further, the sideband intensity showed little dependence with the operating temperature of the QCL, allowing sideband generation to be realized at room temperature.

Molecular cloning of a Candida albicans gene (SSB1) coding for a protein related to the Hsp70 family.

PubMed

Maneu, V; Cervera, A M; Martinez, J P; Gozalbo, D

1997-06-15

We have cloned and sequenced a Candida albicans gene (SSB1) encoding a potential member of the heat-shock protein seventy (hsp70) family. The protein encoded by this gene contains 613 amino acids and shows a high degree (85%) of sequence identity to the ssb subfamily (ssb1 and ssb2) of the Saccharomyces cerevisiae hsp70 family. The transcribed mRNA (2.1 kb) is present in similar amounts both in yeast and germ tube cells of C. albicans.

Derivation of sideband gain ratio for Herschel/HIFI

NASA Astrophysics Data System (ADS)

Kester, Do; Higgins, Ronan; Teyssier, David

2017-03-01

Context. Heterodyne mixers are commonly used for high-resolution spectroscopy at radio telescopes. When used as a double sideband system, the accurate flux calibration of spectral lines acquired by those detectors is highly dependent on the system gains in the respective mixer sidebands via the so-called sideband gain ratio (SBR). As such, the SBR was one of the main contributors to the calibration uncertainty budget of the Herschel/HIFI instrument. Aims: We want to determine the HIFI instrument sideband gain ratio for all bands on a fine frequency grid and within an accuracy of a few percent. Methods: We introduce a novel technique involving in-orbit HIFI data that is bootstrapped onto standard methods involving laboratory data measurements of the SBR. We deconvolved the astronomical data to provide a proxy of the expected signal at every frequency channel, and extracted the sideband gain ratios from the residuals of that process. Results: We determine the HIFI sideband gain ratio to an accuracy varying between 1 and 4%, with degraded accuracy in higher frequency ranges, and at places where the reliability of the technique is lower. These figures were incorporated into the HIFI data processing pipeline and improved the overall flux uncertainty of the legacy data from this instrument. Conclusions: We demonstrate that a modified sideband deconvolution algorithm, using astronomical data in combination with gas cell measurements, can be used to generate an accurate and fine-granularity picture of the sideband gain ratio behaviour of a heterodyne receiver. Herschel is an ESA space observatory with science instruments provided by European-led Principal Investigator consortia and with important participation from NASA.

PriC-mediated DNA replication restart requires PriC complex formation with the single-stranded DNA-binding protein.

PubMed

Wessel, Sarah R; Marceau, Aimee H; Massoni, Shawn C; Zhou, Ruobo; Ha, Taekjip; Sandler, Steven J; Keck, James L

2013-06-14

Frequent collisions between cellular DNA replication complexes (replisomes) and obstacles such as damaged DNA or frozen protein complexes make DNA replication fork progression surprisingly sporadic. These collisions can lead to the ejection of replisomes prior to completion of replication, which, if left unrepaired, results in bacterial cell death. As such, bacteria have evolved DNA replication restart mechanisms that function to reload replisomes onto abandoned DNA replication forks. Here, we define a direct interaction between PriC, a key Escherichia coli DNA replication restart protein, and the single-stranded DNA-binding protein (SSB), a protein that is ubiquitously associated with DNA replication forks. PriC/SSB complex formation requires evolutionarily conserved residues from both proteins, including a pair of Arg residues from PriC and the C terminus of SSB. In vitro, disruption of the PriC/SSB interface by sequence changes in either protein blocks the first step of DNA replication restart, reloading of the replicative DnaB helicase onto an abandoned replication fork. Consistent with the critical role of PriC/SSB complex formation in DNA replication restart, PriC variants that cannot bind SSB are non-functional in vivo. Single-molecule experiments demonstrate that PriC binding to SSB alters SSB/DNA complexes, exposing single-stranded DNA and creating a platform for other proteins to bind. These data lead to a model in which PriC interaction with SSB remodels SSB/DNA structures at abandoned DNA replication forks to create a DNA structure that is competent for DnaB loading.

SSB-1 of the yeast Saccharomyces cerevisiae is a nucleolar-specific, silver-binding protein that is associated with the snR10 and snR11 small nuclear RNAs

PubMed Central

1990-01-01

SSB-1, the yeast single-strand RNA-binding protein, is demonstrated to be a yeast nucleolar-specific, silver-binding protein. In double-label immunofluorescence microscopy experiments antibodies to two other nucleolar proteins, RNA Pol I 190-kD and fibrillarin, were used to reveal the site of rRNA transcription; i.e., the fibrillar region of the nucleolus. SSB-1 colocalized with fibrillarin in a double-label immunofluorescence mapping experiment to the yeast nucleolus. SSB-1 is located, though, over a wider region of the nucleolus than the transcription site marker. Immunoprecipitations of yeast cell extracts with the SSB-1 antibody reveal that in 150 mM NaCl SSB-1 is bound to two small nuclear RNAs (snRNAs). These yeast snRNAs are snR10 and snR11, with snR10 being predominant. Since snR10 has been implicated in pre-rRNA processing, the association of SSB-1 and snR10 into a nucleolar snRNP particle indicates SSB-1 involvement in rRNA processing as well. Also, another yeast protein, SSB-36-kD, isolated by single- strand DNA chromatography, is shown to bind silver under the conditions used for nucleolar-specific staining. It is, most likely, another yeast nucleolar protein. PMID:2121740

Roles of Bacillus subtilis DprA and SsbA in RecA-mediated genetic recombination.

PubMed

Yadav, Tribhuwan; Carrasco, Begoña; Serrano, Ester; Alonso, Juan C

2014-10-03

Bacillus subtilis competence-induced RecA, SsbA, SsbB, and DprA are required to internalize and to recombine single-stranded (ss) DNA with homologous resident duplex. RecA, in the ATP · Mg(2+)-bound form (RecA · ATP), can nucleate and form filament onto ssDNA but is inactive to catalyze DNA recombination. We report that SsbA or SsbB bound to ssDNA blocks the RecA filament formation and fails to activate recombination. DprA facilitates RecA filamentation; however, the filaments cannot engage in DNA recombination. When ssDNA was preincubated with SsbA, but not SsbB, DprA was able to activate DNA strand exchange dependent on RecA · ATP. This work demonstrates that RecA · ATP, in concert with SsbA and DprA, catalyzes DNA strand exchange, and SsbB is an accessory factor in the reaction. In contrast, RecA · dATP efficiently catalyzes strand exchange even in the absence of single-stranded binding proteins or DprA, and addition of the accessory factors marginally improved it. We proposed that the RecA-bound nucleotide (ATP and to a lesser extent dATP) might dictate the requirement for accessory factors. © 2014 by The American Society for Biochemistry and Molecular Biology, Inc.

Single-strand DNA binding protein SSB1 facilitates TERT recruitment to telomeres and maintains telomere G-overhangs

PubMed Central

Pandita, Raj K.; Chow, Tracy T.; Udayakumar, Durga; Bain, Amanda L.; Cubeddu, Liza; Hunt, Clayton R.; Shi, Wei; Horikoshi, Nobuo; Zhao, Yong; Wright, Woodring E.; Khanna, Kum Kum; Shay, Jerry W.; Pandita, Tej K.

2015-01-01

Proliferating mammalian stem and cancer cells express telomerase (TERT) in an effort to extend chromosomal G-overhangs and maintain telomere ends. Telomerase-expressing cells also have higher levels of the single-stranded DNA binding protein SSB1, which has a critical role in DNA double-strand break repair. Here we report that SSB1 binds specifically to G-strand telomeric DNA in vitro and associates with telomeres in vivo. SSB1 interacted with the TERT catalytic subunit and regulates its interaction with telomeres. Deletion of SSB1 reduced TERT interaction with telomeres and lead to G-overhang loss. While SSB1 was recruited to DSB sites, we found no corresponding change in TERT levels at these sites, implying that SSB1-TERT interaction relied upon a specific chromatin structure or context. Our findings offer an explanation for how telomerase is recruited to telomeres to facilitate G-strand DNA extension, a critical step in maintaining telomere ends and cell viability in all cancer cells. PMID:25589350

Ultra-Low-Noise W-Band MMIC Detector Modules

NASA Technical Reports Server (NTRS)

Gaier, Todd C.; Samoska, Lorene A.; Kangaslahti, Pekka P.; Van Vinkle, Dan; Tantawi, Sami; Fox, John; Church, Sarah E.; Lau, Jusy M.; Sieth, Matthew M.; Voll, Patricia E.;

Distributed ultrafast fibre laser

PubMed Central

Liu, Xueming; Cui, Yudong; Han, Dongdong; Yao, Xiankun; Sun, Zhipei

2015-01-01

A traditional ultrafast fibre laser has a constant cavity length that is independent of the pulse wavelength. The investigation of distributed ultrafast (DUF) lasers is conceptually and technically challenging and of great interest because the laser cavity length and fundamental cavity frequency are changeable based on the wavelength. Here, we propose and demonstrate a DUF fibre laser based on a linearly chirped fibre Bragg grating, where the total cavity length is linearly changeable as a function of the pulse wavelength. The spectral sidebands in DUF lasers are enhanced greatly, including the continuous-wave (CW) and pulse components. We observe that all sidebands of the pulse experience the same round-trip time although they have different round-trip distances and refractive indices. The pulse-shaping of the DUF laser is dominated by the dissipative processes in addition to the phase modulations, which makes our ultrafast laser simple and stable. This laser provides a simple, stable, low-cost, ultrafast-pulsed source with controllable and changeable cavity frequency. PMID:25765454

Raman gas self-organizing into deep nano-trap lattice

PubMed Central

Alharbi, M.; Husakou, A.; Chafer, M.; Debord, B.; Gérôme, F.; Benabid, F.

2016-01-01

Trapping or cooling molecules has rallied a long-standing effort for its impact in exploring new frontiers in physics and in finding new phase of matter for quantum technologies. Here we demonstrate a system for light-trapping molecules and stimulated Raman scattering based on optically self-nanostructured molecular hydrogen in hollow-core photonic crystal fibre. A lattice is formed by a periodic and ultra-deep potential caused by a spatially modulated Raman saturation, where Raman-active molecules are strongly localized in a one-dimensional array of nanometre-wide sections. Only these trapped molecules participate in stimulated Raman scattering, generating high-power forward and backward Stokes continuous-wave laser radiation in the Lamb–Dicke regime with sub-Doppler emission spectrum. The spectrum exhibits a central line with a sub-recoil linewidth as low as ∼14 kHz, more than five orders of magnitude narrower than conventional-Raman pressure-broadened linewidth, and sidebands comprising Mollow triplet, motional sidebands and four-wave mixing. PMID:27677451

Multiband DSB-SC modulated radio over IsOWC link with coherent homodyne detection

NASA Astrophysics Data System (ADS)

Kang, Zong; Zhu, Jiang

2018-02-01

In this paper, we present a multiband double sideband-suppressed carrier (DSB-SC) modulated radio over intersatellite optical wireless communication (IsOWC) link with coherent homodyne detection. The proposed system can provide the transparent transport of multiband radio frequency (RF) signals with higher linearity and better receiver sensitivity than the intensity modulated with direct detection (IM/DD) scheme. The full system model and the exactly analytical expression of signal to noise and distortion ratio (SNDR) are derived considering the third-order intermodulation product and amplifier spontaneous emission (ASE) noise. The finite extinction ratio (ER) of Mach-Zehnder Modulator (MZM) and the saturation property of erbium doped fiber amplifier (EDFA) are also considered. Numerical results of SNDR with various numbers of subchannels and ERs are given. Results indicate that the optimal modulation index exists to maximize the SNDR and the power of local oscillator (LO) carrier should be within an appropriate range.

Dual-tone optical vector millimeter wave signal generated by frequency-nonupling the radio frequency 16-star quadrature-amplitude-modulation signal

NASA Astrophysics Data System (ADS)

Wu, Tonggen; Ma, Jianxin

2017-12-01

This paper proposes an original scheme to generate the photonic dual-tone optical millimeter wave (MMW) carrying the 16-star quadrature-amplitude-modulation (QAM) signal via an optical phase modulator (PM) and an interleaver with adaptive photonic frequency-nonupling without phase precoding. To enable the generated optical vector MMW signal to resist the power fading effect caused by the fiber chromatic dispersion, the modulated -5th- and +4th-order sidebands are selected from the output of the PM, which is driven by the precoding 16-star QAM signal. The modulation index of the PM is optimized to gain the maximum opto-electrical conversion efficiency. A radio over fiber link is built by simulation, and the simulated constellations and the bit error rate graph demonstrate that the frequency-nonupling 16-star QAM MMW signal has good transmission performance. The simulation results agree well with our theoretical results.

Children's sugar-sweetened beverages consumption: associations with family and home-related factors, differences within ethnic groups explored.

PubMed

van de Gaar, V M; van Grieken, A; Jansen, W; Raat, H

2017-02-14

The consumption of sugar-sweetened beverages (SSB) may contribute to the development of overweight among children. The present study aimed to evaluate associations between family and home-related factors and children's SSB consumption. We explored associations within ethnic background of the child. Cross-sectional data from the population-based 'Water Campaign' study were used. Parents (n = 644) of primary school children (6-13 years) completed a questionnaire on socio-demographic characteristics, family and home-related factors and child's SSB intake. The family and home-related factors under study were: cognitive variables (e.g. parental attitude, subjective norm), environmental variables (e.g. availability of SSB, parenting practices), and habitual variables (e.g. habit strength, taste preference). Regression analyses were used to evaluate the associations between family and home-related factors and child's SSB intake (p < 0.05). Mean age of the children was 9.4 years (SD: 1.8) and 54.1% were girls. The child's average SSB intake was 0.9 litres (SD: 0.6) per day. Child's age, parents' subjective norm, parenting practices, and parental modelling were positively associated with the child's SSB intake. The availability of SSB at home and school and parental attitude were negatively associated with the child's SSB intake. The associations under study differed according to the child's ethnic background, with the explained variance of the full models ranging from 8.7% for children from Moroccan or Turkish ethnic background to 44.4% for children with Dutch ethnic background. Our results provide support for interventions targeting children's SSB intake focussing on the identified family and home-related factors, with active participation of parents. Also, the relationships between these factors and the child's SSB intake differed for children with distinct ethnic backgrounds. Therefore, we would recommend to tailor interventions taking into account the ethnic background of the family. Number NTR3400 ; date April 4th 2012; retrospectively registered.

Association of Sugar-Sweetened Beverage Intake during Infancy with Dental Caries in 6-year-olds

PubMed Central

Lin, Mei; Onufrak, Stephen; Li, Ruowei

2015-01-01

To examine whether sugar-sweetened beverage (SSB) intake during infancy is associated with dental caries by age 6, a longitudinal analysis of 1,274 U.S. children was conducted using data from the 2005-2007 Infant Feeding Practices Study II and the 2012 Follow-up Study at 6 years of age. The exposure variables were maternal-reported SSB intakes during infancy (i.e., any SSB intake during infancy, age at SSB introduction during infancy, and average frequency of SSB intake during 10-12 months of age). The outcome variable was maternal-reported dental caries of their 6-year-old in his/her lifetime. Multivariable logistic regression analyses were used to calculate adjusted odds ratios (aOR) for associations of SSB intake during infancy with having dental caries among 6-year-olds after controlling for baseline characteristics of children and mothers and child's tooth brushing habits and sweet food intake at follow-up. Based on maternal recall, almost 40% of 6-year-olds had dental caries in their lifetime. Adjusted odds of having dental caries was significantly associated with higher frequency of SSB intake during 10-12 months (aOR=1.83 for ≥3 times/week, vs. none). Any SSB intake during infancy and age at SSB introduction during infancy were not associated with dental caries. In conclusion, frequent SSB intake during 10-12 months of age significantly increased the likelihood of having dental caries among 6-year-olds. Late infancy may be an important time for mothers to establish healthy beverage practices for their children. These findings can be used to inform efforts to reduce dental caries among children. PMID:25713788

Association of sugar-sweetened beverage intake frequency and asthma among U.S. adults, 2013

PubMed Central

Park, Sohyun; Akinbami, Lara J.; McGuire, Lisa C.; Blanck, Heidi M.

2016-01-01

Objectives Sugar-sweetened beverage (SSB) intake among U.S. adults is associated with obesity and type 2 diabetes. An association between SSB intake and asthma has been shown among U.S. children and Australian adults, but scant published information exists for U.S. adults. We examined associations between SSB intake and current asthma among U.S. adults, and the role of obesity in this association. Methods We analyzed 2013 Behavioral Risk Factor Surveillance System data for 146,990 adults (≥18 years) from 23 states and the District of Columbia. We used multivariable logistic regression to estimate associations between current asthma and frequency (none, <1 time/day, once/day, ≥2 times/day) of SSB intake (soda, fruit drink, sweet tea, and sports/energy drink). SSB intake was measured using two questions. Covariates included age, sex, race/ethnicity, education, and smoking. Obesity, based on self-reported height and weight, was assessed as an effect modifier. Results Overall, 9.1% of adults reported current asthma: 8.5% of adults who did not consume SSBs had current asthma vs 12.1% of adults who consumed SSBs ≥2 times/day. There was no difference in asthma prevalence with SSB intake <1 time/day (8.7%) or once/day (8.7%). Among non-obese adults, the odds of having current asthma were higher among those who consumed SSBs ≥2 times/day (aOR=1.66, 95%CI=1.39, 1.99) than non-SSB consumers. However, SSB intake frequency was not associated with asthma among obese adults. Conclusions Frequent SSB consumption was associated with asthma among non-obese adults. Research on asthma prevention should further consider the potential adverse effects of high SSB intake among U.S. adults. PMID:27496394

Support for Food and Beverage Worksite Wellness Strategies and Sugar-Sweetened Beverage Intake Among Employed U.S. Adults.

PubMed

Lee-Kwan, Seung Hee; Pan, Liping; Kimmons, Joel; Foltz, Jennifer; Park, Sohyun

2017-03-01

Sugar-sweetened beverage (SSB) consumption is high among U.S. adults and is associated with obesity. Given that more than 100 million Americans consume food or beverages at work daily, the worksite may be a venue for interventions to reduce SSB consumption. However, the level of support for these interventions is unknown. We examined associations between workday SSB intake and employees' support for worksite wellness strategies (WWSs). We conducted a cross-sectional study using data from Web-based annual surveys that gather information on health-related attitudes and behaviors. Study setting was the United States. A total of 1924 employed adults (≥18 years) selected using probability-based sampling. The self-reported independent variable was workday SSB intake (0, <1 or ≥1 times per day), and dependent variables were employees' support (yes/no) for the following WWSs: (1) accessible free water, (2) affordable healthy food/drink, (3) available healthy options, and (4) less available SSB. Multivariable logistic regression was used to control for sociodemographic variables, employee size, and availability of cafeteria/vending machine. About half of employees supported accessible free water (54%), affordable healthy food/drink (49%), and available healthy options (46%), but only 28% supported less available SSB. Compared with non-SSB consumers, daily SSB consumers were significantly less supportive of accessible free water (adjusted odds ratio, .67; p < .05) or less available SSB (odds ratio, .49; p < .05). Almost half of employees supported increasing healthy options within worksites, although daily workday SSB consumers were less supportive of certain strategies. Lack of support could be a potential barrier to the successful implementation of certain worksite interventions.

Self-regulation Interventions for the Reduction of Sugar-Sweetened Beverages in Adolescents

PubMed Central

Ames, Susan L.; Wurpts, Ingrid C.; Pike, James; MacKinnon, David P.; Reynolds, Kim R.; Stacy, Alan W.

2017-01-01

This study evaluated the efficacy of self-regulation interventions through the use of drink-specific implementation intentions and drink-specific Go/No-Go training tasks as compensatory strategies to modify inhibitory control to reduce intake of sugar-sweetened beverages (SSB). In a between-subjects randomized manipulation of implementation intentions and Go/No-Go training to learn to inhibit sugary drink consumption, 168 adolescents reporting inhibitory control problems over sugary drinks and foods were recruited from high schools in southern California to participate. Analysis of covariance overall test of effects revealed no significant differences between the groups regarding calories consumed, calories from SSBs, grams of sugar consumed from drinks, or the number of unhealthy drinks chosen. However, subsequent contrasts revealed SSB implementation intentions significantly reduced SSB consumption following intervention while controlling for inhibitory control failure and general SSB consumption during observation in a lab setting that provided SSBs and healthy drinks, as well as healthy and unhealthy snacks. Specifically, during post-intervention observation, participants in the sugar-sweetened beverage implementation intentions (SSB-II) conditions consumed significantly fewer calories overall, fewer calories from drinks, and fewer grams of sugar. No effects were found for the drink-specific Go/No-Go training on SSB or calorie consumption. However, participants in SSB-II with an added SSB Go/No-Go training made fewer unhealthy drink choices than those in the other conditions. Implementation intentions may aid individuals with inhibitory (executive control) difficulties by intervening on pre-potent behavioral tendencies, like SSB consumption. PMID:27374899

Cancer-Related Information Seeking and Scanning Behavior of Older Vietnamese Immigrants

PubMed Central

Nguyen, Giang T.; Shungu, Nicholas P.; Niederdeppe, Jeff; Barg, Frances K.; Holmes, John H.; Armstrong, Katrina; Hornik, Robert C.

2010-01-01

Information seeking and scanning refers to active pursuit of information and passive exposure, respectively. Cancer (ca) is the leading cause of mortality for Asian Americans, yet little is known about their ca information seeking/scanning behaviors (SSB). We aimed to evaluate ca SSB among older limited English proficient (LEP) Vietnamese immigrants, compared to Whites/African Americans. 104 semi-structured interviews about breast/prostate/colon ca SSB (age 50–70) were conducted in English and Vietnamese, transcribed, and coded for frequency of source use, active/passive nature, depth of recall, and relevance to decisions. Higher SSB was associated with ca screening. In contrast to non-Vietnamese, SSB for Vietnamese was low. Median # of ca screening sources was 2 (vs. 8–9 for non-Vietnamese). They also had less seeking, lower recall, and less decision-making relevance for information on colon ca and all ca combined. Overall, Vietnamese had lower use of electronic, print, and interpersonal sources for ca SSB, but more research is needed to disentangle potential effects of ethnicity and education. This study brings to light striking potential differences between ca SSB of older LEP Vietnamese compared to Whites/African Americans. Knowledge of SSB patterns among linguistically isolated communities is essential for efficient dissemination of cancer information to these at-risk communities. PMID:21104504

Sugar-Sweetened Beverage Consumption by Adult Caregivers and Their Children: The Role of Drink Features and Advertising Exposure.

PubMed

Hennessy, Michael; Bleakley, Amy; Piotrowski, Jessica Taylor; Mallya, Giridhar; Jordan, Amy

2015-10-01

To examine how parents' beliefs about beverage attributes and exposure to sugar-sweetened beverage (SSB) advertising are associated with parents' and their children's SSB consumption. Cross-sectional representative telephone survey of Philadelphia parents in households with children between the ages of 3 and 16 years. Three hundred and seventy-one randomly selected survey respondents. The response rate was 27% using the American Association for Public Opinion Research RR3 formula. SSB consumption, health ratings of SSBs, exposure to SSB ads, and exposure to anti-SSB public service advertisements. Seemingly unrelated regression was used to correct for Type I error and significance levels were set at .05 or less. Assessment of SSB "healthiness" was associated with the increased adult consumption of SSBs for three of the five SSBs and associated with children's consumption for all four SSBs with child consumption data. For both groups, ratings of SSB sugar and caloric content were not related to consumption. Adult exposure to SSB-specific advertising was related to consumption for three of five SSBs and two of four SSBs consumed by children. These results suggest that sugar and calories are not relevant to consumption, absent an explicit connection to a healthiness evaluation of SSBs. © 2015 Society for Public Health Education.

Cancer-related information seeking and scanning behavior of older Vietnamese immigrants.

PubMed

Nguyen, Giang T; Shungu, Nicholas P; Niederdeppe, Jeff; Barg, Frances K; Holmes, John H; Armstrong, Katrina; Hornik, Robert C

2010-10-01

Information seeking and scanning refers to active pursuit of information and passive exposure, respectively. Cancer is the leading cause of mortality for Asian Americans, yet little is known about their cancer information seeking/scanning behaviors (SSB). We aimed to evaluate cancer SSB among older limited English proficient (LEP) Vietnamese immigrants, compared with Whites/African Americans. One hundred four semistructured interviews about breast/prostate/colon cancer SSB (ages 50-70) were conducted in English and Vietnamese, transcribed, and coded for frequency of source use, active/passive nature, depth of recall, and relevance to decisions. Higher SSB was associated with cancer screening. In contrast to non-Vietnamese, SSB for Vietnamese was low. Median number of cancer screening sources was two (vs. eight to nine for non-Vietnamese). They also had less seeking, lower recall, and less decision-making relevance for information on colon cancer and all cancers combined. Overall, Vietnamese had lower use of electronic, print, and interpersonal sources for cancer SSB, but more research is needed to disentangle potential effects of ethnicity and education. This study brings to light striking potential differences between cancer SSB of older LEP Vietnamese compared with Whites/African Americans. Knowledge of SSB patterns among linguistically isolated communities is essential for efficient dissemination of cancer information to these at-risk communities.

Continuous-wave modulation of a femtosecond oscillator using coherent molecules.

PubMed

Gold, D C; Karpel, J T; Mueller, E A; Yavuz, D D

2018-03-01

We describe a new method to broaden the frequency spectrum of a femtosecond oscillator in the continuous-wave (CW) domain. The method relies on modulating the femtosecond laser using four-wave mixing inside a Raman-based optical modulator. We prepare the modulator by placing deuterium molecules inside a high-finesse cavity and driving their fundamental vibrational transition using intense pump and Stokes lasers that are locked to the cavity modes. With the molecules prepared, any laser within the optical region of the spectrum can pass through the system and be modulated in a single pass. This constitutes a CW optical modulator at a frequency of 90 THz with a steady-state single-pass efficiency of ∼10 -6 and transient (10 μs-time-scale) single-pass efficiency of ∼10 -4 . Using our modulator, we broaden the initial Ti:sapphire spectrum centered at 800 nm and produce upshifted and downshifted sidebands centered at wavelengths of 650 nm and 1.04 μm, respectively.

Automating ATLAS Computing Operations using the Site Status Board

NASA Astrophysics Data System (ADS)

J, Andreeva; Iglesias C, Borrego; S, Campana; Girolamo A, Di; I, Dzhunov; Curull X, Espinal; S, Gayazov; E, Magradze; M, Nowotka M.; L, Rinaldi; P, Saiz; J, Schovancova; A, Stewart G.; M, Wright

2012-12-01

The automation of operations is essential to reduce manpower costs and improve the reliability of the system. The Site Status Board (SSB) is a framework which allows Virtual Organizations to monitor their computing activities at distributed sites and to evaluate site performance. The ATLAS experiment intensively uses the SSB for the distributed computing shifts, for estimating data processing and data transfer efficiencies at a particular site, and for implementing automatic exclusion of sites from computing activities, in case of potential problems. The ATLAS SSB provides a real-time aggregated monitoring view and keeps the history of the monitoring metrics. Based on this history, usability of a site from the perspective of ATLAS is calculated. The paper will describe how the SSB is integrated in the ATLAS operations and computing infrastructure and will cover implementation details of the ATLAS SSB sensors and alarm system, based on the information in the SSB. It will demonstrate the positive impact of the use of the SSB on the overall performance of ATLAS computing activities and will overview future plans.

Novel, fluorescent, SSB protein chimeras with broad utility

PubMed Central

Liu, Juan; Choi, Meerim; Stanenas, Adam G; Byrd, Alicia K; Raney, Kevin D; Cohan, Christopher; Bianco, Piero R

2011-01-01

The Escherichia coli single-stranded DNA binding protein (SSB) is a central player in DNA metabolism where it organizes genome maintenance complexes and stabilizes single-stranded DNA (ssDNA) intermediates generated during DNA processing. Due to the importance of SSB and to facilitate real-time studies, we developed a dual plasmid expression system to produce novel, chimeric SSB proteins. These chimeras, which contain mixtures of histidine-tagged and fluorescent protein(FP)-fusion subunits, are easily purified in milligram quantities and used without further modification, a significant enhancement over previous methods to produce fluorescent SSB. Chimeras retain the functionality of wild type in all assays, demonstrating that SSB function is unaffected by the FPs. We demonstrate the power and utility of these chimeras in single molecule studies providing a great level of insight into the biochemical mechanism of RecBCD. We also utilized the chimeras to show for the first time that RecG and SSB interact in vivo. Consequently, we anticipate that the chimeras described herein will facilitate in vivo, in vitro and single DNA molecule studies using proteins that do not require further modification prior to use. PMID:21462278

Towards a centralized Grid Speedometer

NASA Astrophysics Data System (ADS)

Dzhunov, I.; Andreeva, J.; Fajardo, E.; Gutsche, O.; Luyckx, S.; Saiz, P.

2014-06-01

Given the distributed nature of the Worldwide LHC Computing Grid and the way CPU resources are pledged and shared around the globe, Virtual Organizations (VOs) face the challenge of monitoring the use of these resources. For CMS and the operation of centralized workflows, the monitoring of how many production jobs are running and pending in the Glidein WMS production pools is very important. The Dashboard Site Status Board (SSB) provides a very flexible framework to collect, aggregate and visualize data. The CMS production monitoring team uses the SSB to define the metrics that have to be monitored and the alarms that have to be raised. During the integration of CMS production monitoring into the SSB, several enhancements to the core functionality of the SSB were required; They were implemented in a generic way, so that other VOs using the SSB can exploit them. Alongside these enhancements, there were a number of changes to the core of the SSB framework. This paper presents the details of the implementation and the advantages for current and future usage of the new features in SSB.

Projected Impact of Mexico's Sugar-Sweetened Beverage Tax Policy on Diabetes and Cardiovascular Disease: A Modeling Study.

PubMed

Sánchez-Romero, Luz Maria; Penko, Joanne; Coxson, Pamela G; Fernández, Alicia; Mason, Antoinette; Moran, Andrew E; Ávila-Burgos, Leticia; Odden, Michelle; Barquera, Simón; Bibbins-Domingo, Kirsten

2016-11-01

Rates of diabetes in Mexico are among the highest worldwide. In 2014, Mexico instituted a nationwide tax on sugar-sweetened beverages (SSBs) in order to reduce the high level of SSB consumption, a preventable cause of diabetes and cardiovascular disease (CVD). We used an established computer simulation model of CVD and country-specific data on demographics, epidemiology, SSB consumption, and short-term changes in consumption following the SSB tax in order to project potential long-range health and economic impacts of SSB taxation in Mexico. We used the Cardiovascular Disease Policy Model-Mexico, a state transition model of Mexican adults aged 35-94 y, to project the potential future effects of reduced SSB intake on diabetes incidence, CVD events, direct diabetes healthcare costs, and mortality over 10 y. Model inputs included short-term changes in SSB consumption in response to taxation (price elasticity) and data from government and market research surveys and public healthcare institutions. Two main scenarios were modeled: a 10% reduction in SSB consumption (corresponding to the reduction observed after tax implementation) and a 20% reduction in SSB consumption (possible with increases in taxation levels and/or additional measures to curb consumption). Given uncertainty about the degree to which Mexicans will replace calories from SSBs with calories from other sources, we evaluated a range of values for calorie compensation. We projected that a 10% reduction in SSB consumption with 39% calorie compensation among Mexican adults would result in about 189,300 (95% uncertainty interval [UI] 155,400-218,100) fewer incident type 2 diabetes cases, 20,400 fewer incident strokes and myocardial infarctions, and 18,900 fewer deaths occurring from 2013 to 2022. This scenario predicts that the SSB tax could save Mexico 983 million international dollars (95% UI $769 million-$1,173 million). The largest relative and absolute reductions in diabetes and CVD events occurred in the youngest age group modeled (35-44 y). This study's strengths include the use of an established mathematical model of CVD and use of contemporary Mexican vital statistics, data from health surveys, healthcare costs, and SSB price elasticity estimates as well as probabilistic and deterministic sensitivity analyses to account for uncertainty. The limitations of the study include reliance on US-based studies for certain inputs where Mexico-specific data were lacking (specifically the associations between risk factors and CVD outcomes [from the Framingham Heart Study] and SSB calorie compensation assumptions), limited data on healthcare costs other than those related to diabetes, and lack of information on long-term SSB price elasticity that is specific to geographic and economic subgroups. Mexico's high diabetes prevalence represents a public health crisis. While the long-term impact of Mexico's SSB tax is not yet known, these projections, based on observed consumption reductions, suggest that Mexico's SSB tax may substantially decrease morbidity and mortality from diabetes and CVD while reducing healthcare costs.

76 FR 72885 - FM Asymmetric Sideband Operation and Associated Technical Studies

Federal Register 2010, 2011, 2012, 2013, 2014

2011-11-28

... Sideband Operation and Associated Technical Studies AGENCY: Federal Communications Commission. ACTION... Asymmetric Sideband Operation and Associated Technical Studies, MM Docket No. 99-325, Public Notice, DA 11-1832 (MB rel. Nov. 1, 2011). The iBiquity and NPR request and the iBiquity and NPR technical studies...

Public support for a sugar-sweetened beverage tax and pro-tax messages in a Mid-Atlantic US state

PubMed Central

Donaldson, Elisabeth A; Cohen, Joanna E; Rutkow, Lainie; Villanti, Andrea C; Kanarek, Norma F; Barry, Colleen L

2015-01-01

Objective To examine the characteristics of supporters and opponents of a sugar-sweetened beverage (SSB) tax and to identify pro-tax messages that resonate with the public. Design A survey was administered by telephone in February 2013 to assess public opinion about a penny-per-ounce tax on SSB. Support was also examined for SSB consumption reduction and pro-tax messages. Individual characteristics including sociodemographics, political affiliation, SSB consumption behaviours and beliefs were explored as predictors of support using logistic regression. Setting A representative sample of voters was recruited from a Mid-Atlantic US state. Subjects The sample included 1000 registered voters. Results Findings indicate considerable support (50 %) for an SSB tax. Support was stronger among Democrats, those who believe SSB are a major cause of childhood obesity and those who believe childhood obesity warrants a societal intervention. Belief that a tax would be effective in lowering obesity rates was associated with support for the tax and pro-tax messages. Respondents reporting that a health-care provider had recommended they lose weight were less convinced by pro-tax messages. Women, Independents and those concerned about childhood obesity were more convinced by the SSB reduction messages. Overall, the most popular messages focused on the importance of reducing consumption among children without mentioning the tax. Conclusions Understanding who supports and opposes SSB tax measures can assist advocates in developing strategies to maximize support for this type of intervention. Messages that focus on the effect of consumption on children may be useful in framing the discussion around SSB tax proposals. PMID:25430945

Self-regulation interventions to reduce consumption of sugar-sweetened beverages in adolescents.

PubMed

Ames, Susan L; Wurpts, Ingrid C; Pike, James R; MacKinnon, David P; Reynolds, Kim R; Stacy, Alan W

2016-10-01

This study evaluated the efficacy of self-regulation interventions through the use of drink-specific implementation intentions and drink-specific Go/No-Go training tasks as compensatory strategies to modify inhibitory control to reduce intake of sugar-sweetened beverages (SSB). In a between-subjects randomized manipulation of implementation intentions and Go/No-Go training to learn to inhibit sugary drink consumption, 168 adolescents reporting inhibitory control problems over sugary drinks and foods were recruited from high schools in southern California to participate. Analysis of covariance overall test of effects revealed no significant differences between the groups regarding calories consumed, calories from SSBs, grams of sugar consumed from drinks, or the number of unhealthy drinks chosen. However, subsequent contrasts revealed SSB implementation intentions significantly reduced SSB consumption following intervention while controlling for inhibitory control failure and general SSB consumption during observation in a lab setting that provided SSBs and healthy drinks, as well as healthy and unhealthy snacks. Specifically, during post-intervention observation, participants in the sugar-sweetened beverage implementation intentions (SSB-II) conditions consumed significantly fewer calories overall, fewer calories from drinks, and fewer grams of sugar. No effects were found for the drink-specific Go/No-Go training on SSB or calorie consumption. However, participants in SSB-II with an added SSB Go/No-Go training made fewer unhealthy drink choices than those in the other conditions. Implementation intentions may aid individuals with inhibitory (executive control) difficulties by intervening on pre-potent behavioral tendencies, like SSB consumption. Copyright © 2016. Published by Elsevier Ltd.

Public support for a sugar-sweetened beverage tax and pro-tax messages in a Mid-Atlantic US state.

PubMed

Donaldson, Elisabeth A; Cohen, Joanna E; Rutkow, Lainie; Villanti, Andrea C; Kanarek, Norma F; Barry, Colleen L

2015-08-01

To examine the characteristics of supporters and opponents of a sugar-sweetened beverage (SSB) tax and to identify pro-tax messages that resonate with the public. A survey was administered by telephone in February 2013 to assess public opinion about a penny-per-ounce tax on SSB. Support was also examined for SSB consumption reduction and pro-tax messages. Individual characteristics including sociodemographics, political affiliation, SSB consumption behaviours and beliefs were explored as predictors of support using logistic regression. A representative sample of voters was recruited from a Mid-Atlantic US state. The sample included 1000 registered voters. Findings indicate considerable support (50 %) for an SSB tax. Support was stronger among Democrats, those who believe SSB are a major cause of childhood obesity and those who believe childhood obesity warrants a societal intervention. Belief that a tax would be effective in lowering obesity rates was associated with support for the tax and pro-tax messages. Respondents reporting that a health-care provider had recommended they lose weight were less convinced by pro-tax messages. Women, Independents and those concerned about childhood obesity were more convinced by the SSB reduction messages. Overall, the most popular messages focused on the importance of reducing consumption among children without mentioning the tax. Understanding who supports and opposes SSB tax measures can assist advocates in developing strategies to maximize support for this type of intervention. Messages that focus on the effect of consumption on children may be useful in framing the discussion around SSB tax proposals.

Picosecond Electronics and Optoelectronics Held at Incline Village, Nevada on 13-15 March 1985.

DTIC Science & Technology

1986-02-04

subpicosecond Observation of Modulation Speed Enhancement and laser pulses in s-lO n -si icrn Scnbttky diodes s in Phase Noise Reduction by Detuned Loading in...desadaptation is necessary for saving power dissipation so that multiple reflexions and inter connexion cross-talk noise could become the source of the...r : I:, .i . .. ,: V) i’). noise sidebands predominate. Because the samnler measures the product of the optical intensity and the electrical signal

Test and Evaluation of Reduced Rate Multiplexers.

DTIC Science & Technology

1981-08-01

employed by your organization , please notify RADC. (DCLp) Griffiss AFB NY 13441. This will assist .us in maintaining a current mailin list. Do not return...be organized as follows. There will be some general discussions applicable to the overall program. A separate section will be devoted to each of the...modulation transmitted as a vestigial . sideband line signal, -16 dB carrier 2853 Hz added in quadrature, 4 level 4800 baud 9600 BIS, 4800/7200/9600 B

Mechanisms underlying intensity-dependent changes in cortical selectivity for frequency-modulated sweeps.

PubMed

Razak, K A

2012-04-01

Frequency-modulated (FM) sweeps are common components of species-specific vocalizations. The intensity of FM sweeps can cover a wide range in the natural environment, but whether intensity affects neural selectivity for FM sweeps is unclear. Bats, such as the pallid bat, which use FM sweeps for echolocation, are suited to address this issue, because the intensity of echoes will vary with target distance. In this study, FM sweep rate selectivity of pallid bat auditory cortex neurons was measured using downward sweeps at different intensities. Neurons became more selective for FM sweep rates present in the bat's echolocation calls as intensity increased. Increased selectivity resulted from stronger inhibition of responses to slower sweep rates. The timing and bandwidth of inhibition generated by frequencies on the high side of the excitatory tuning curve [sideband high-frequency inhibition (HFI)] shape rate selectivity in cortical neurons in the pallid bat. To determine whether intensity-dependent changes in FM rate selectivity were due to altered inhibition, the timing and bandwidth of HFI were quantified at multiple intensities using the two-tone inhibition paradigm. HFI arrived faster relative to excitation as sound intensity increased. The bandwidth of HFI also increased with intensity. The changes in HFI predicted intensity-dependent changes in FM rate selectivity. These data suggest that neural selectivity for a sweep parameter is not static but shifts with intensity due to changes in properties of sideband inhibition.

The RecF protein antagonizes RecX function via direct interaction

PubMed Central

Lusetti, Shelley L.; Hobbs, Michael D.; Stohl, Elizabeth A.; Chitteni-Pattu, Sindhu; Inman, Ross B.; Seifert, H. Steven; Cox, Michael M.

2014-01-01

Summary The RecX protein inhibits RecA filament extension leading to net filament disassembly. The RecF protein physically interacts with the RecX protein and protects RecA from the inhibitory effects of RecX. In vitro, efficient RecA filament formation onto SSB-coated circular single-stranded DNA in the presence of RecX occurs only when all of the RecFOR proteins are present. The RecOR proteins contribute only to RecA filament nucleation onto SSB-coated single-stranded DNA and are unable to counter the inhibitory effects of RecX on RecA filaments. RecF protein uniquely supports substantial RecA filament extension in the presence of RecX. In vivo, RecF protein counters a RecX-mediated inhibition of plasmid recombination. Thus, a significant positive contribution of RecF to RecA filament assembly is to antagonize the effects of the negative modulator, RecX, specifically during the extension phase. PMID:16387652

Modeling the Effect of Replacing Sugar-Sweetened Beverage Consumption with Water on Energy Intake, HBI Score, and Obesity Prevalence.

PubMed

Duffey, Kiyah J; Poti, Jennifer

2016-06-28

Sugar-sweetened beverages (SSB) contribute to excessive weight gain through added energy intake. Replacing SSB with water is one strategy that has shown promise in helping lower excessive energy intake. Using nationally representative data from US adults (n = 19,718) from NHANES 2007-2012 we examine the impact of replacing SSB with water on Healthy Beverage Index (HBI) scores and obesity prevalence. Replacing an 8-ounce serving of SSB with water lowered the percent of energy from beverages from 17% to 11% (among those consuming 1 serving SSB/day). Reductions in the percent energy from beverages were observed across all SSB consumption groups (1-2 servings/day and >2 servings/day). Among adults there was a 9% to 21% improvement in HBI score when one serving of water replaced one serving of SSB. Using previously published randomized controlled trials (RCT) and meta-analyses of measured weight loss we also predicted a reduction in the prevalence of obesity (observed: 35.2%; predicted 33.5%-34.9%, p < 0.05) and increase in the prevalence of normal weight (observed: 29.7%; high weight loss: 31.3%, p < 0.05). Our findings provide further epidemiologic evidence that water in the place of SSB can be used as a strategy to limit energy intake and help individuals meet beverage intake recommendations.

Effects of an intervention aimed at reducing the intake of sugar-sweetened beverages in primary school children: a controlled trial.

PubMed

van de Gaar, Vivian M; Jansen, Wilma; van Grieken, Amy; Borsboom, Gerard J J M; Kremers, Stef; Raat, Hein

2014-07-25

Since sugar-sweetened beverages (SSB) may contribute to the development of overweight in children, effective interventions to reduce their consumption are needed. Here we evaluated the effect of a combined school- and community-based intervention aimed at reducing children's SSB consumption by promoting the intake of water. Favourable intervention effects on children's SSB consumption were hypothesized. In 2011-2012, a controlled trial was conducted among four primary schools, comprising 1288 children aged 6-12 years who lived in multi-ethnic, socially deprived neighbourhoods in Rotterdam, the Netherlands. Intervention schools adopted the 'water campaign', an intervention developed using social marketing. Control schools continued with their regular health promotion programme. Primary outcome was children's SSB consumption, measured using parent and child questionnaires and through observations at school, both at baseline and after one year of intervention. Significant positive intervention effects were found for average SSB consumption (B -0.19 litres, 95% CI -0.28;-0.10; parent report), average SSB servings (B -0.54 servings, 95% CI -0.82;-0.26; parent report) and bringing SSB to school (OR 0.51, 95% CI 0.36;0.72; observation report). This study supports the effectiveness of the water campaign intervention in reducing children's SSB consumption. Further studies are needed to replicate our findings. Current Controlled Trials: NTR3400.

Determinants of sugar‐sweetened beverage consumption in young children: a systematic review

PubMed Central

Mazarello Paes, V.; Hesketh, K.; O'Malley, C.; Moore, H.; Summerbell, C.; Griffin, S.; van Sluijs, E. M. F.; Ong, K. K.

2015-01-01

Summary Sugar‐sweetened beverage (SSB) consumption is associated with adverse health outcomes. Improved understanding of the determinants will inform effective interventions to reduce SSB consumption. A total of 46,876 papers were identified through searching eight electronic databases. Evidence from intervention (n = 13), prospective (n = 6) and cross‐sectional (n = 25) studies on correlates/determinants of SSB consumption was quality assessed and synthesized. Twelve correlates/determinants were associated with higher SSB consumption (child's preference for SSBs, TV viewing/screen time and snack consumption; parents' lower socioeconomic status, lower age, SSB consumption, formula milk feeding, early introduction of solids, using food as rewards, parental‐perceived barriers, attending out‐of‐home care and living near a fast food/convenience store). Five correlates/determinants were associated with lower SSB consumption (parental positive modelling, parents' married/co‐habiting, school nutrition policy, staff skills and supermarket nearby). There was equivocal evidence for child's age and knowledge, parental knowledge, skills, rules/restrictions and home SSB availability. Eight intervention studies targeted multi‐level (child, parents, childcare/preschool setting) determinants; four were effective. Four intervention studies targeted parental determinants; two were effective. One (effective) intervention targeted the preschool environment. There is consistent evidence to support potentially modifiable correlates/determinants of SSB consumption in young children acting at parental (modelling), child (TV viewing) and environmental (school policy) levels. PMID:26252417

Modeling the Effect of Replacing Sugar-Sweetened Beverage Consumption with Water on Energy Intake, HBI Score, and Obesity Prevalence

PubMed Central

Duffey, Kiyah J.; Poti, Jennifer

2016-01-01

Sugar-sweetened beverages (SSB) contribute to excessive weight gain through added energy intake. Replacing SSB with water is one strategy that has shown promise in helping lower excessive energy intake. Using nationally representative data from US adults (n = 19,718) from NHANES 2007–2012 we examine the impact of replacing SSB with water on Healthy Beverage Index (HBI) scores and obesity prevalence. Replacing an 8-ounce serving of SSB with water lowered the percent of energy from beverages from 17% to 11% (among those consuming 1 serving SSB/day). Reductions in the percent energy from beverages were observed across all SSB consumption groups (1–2 servings/day and >2 servings/day). Among adults there was a 9% to 21% improvement in HBI score when one serving of water replaced one serving of SSB. Using previously published randomized controlled trials (RCT) and meta-analyses of measured weight loss we also predicted a reduction in the prevalence of obesity (observed: 35.2%; predicted 33.5%–34.9%, p < 0.05) and increase in the prevalence of normal weight (observed: 29.7%; high weight loss: 31.3%, p < 0.05). Our findings provide further epidemiologic evidence that water in the place of SSB can be used as a strategy to limit energy intake and help individuals meet beverage intake recommendations. PMID:27367719

Health Benefits of Reducing Sugar-Sweetened Beverage Intake in High Risk Populations of California: Results from the Cardiovascular Disease (CVD) Policy Model

PubMed Central

Mekonnen, Tekeshe A.; Odden, Michelle C.; Coxson, Pamela G.; Guzman, David; Lightwood, James; Wang, Y. Claire; Bibbins-Domingo, Kirsten

2013-01-01

Background Consumption of sugar-sweetened beverage (SSB) has risen over the past two decades, with over 10 million Californians drinking one or more SSB per day. High SSB intake is associated with risk of type 2 diabetes, obesity, hypertension, and coronary heart disease (CHD). Reduction of SSB intake and the potential impact on health outcomes in California and among racial, ethnic, and low-income sub-groups has not been quantified. Methods We projected the impact of reduced SSB consumption on health outcomes among all Californians and California subpopulations from 2013 to 2022. We used the CVD Policy Model – CA, an established computer simulation of diabetes and heart disease adapted to California. We modeled a reduction in SSB intake by 10–20% as has been projected to result from proposed penny-per-ounce excise tax on SSB and modeled varying effects of this reduction on health parameters including body mass index, blood pressure, and diabetes risk. We projected avoided cases of diabetes and CHD, and associated health care cost savings in 2012 US dollars. Results Over the next decade, a 10–20% SSB consumption reduction is projected to result in a 1.8–3.4% decline in the new cases of diabetes and an additional drop of 0.5–1% in incident CHD cases and 0.5–0.9% in total myocardial infarctions. The greatest reductions are expected in African Americans, Mexican Americans, and those with limited income regardless of race and ethnicity. This reduction in SSB consumption is projected to yield $320–620 million in medical cost savings associated with diabetes cases averted and an additional savings of $14–27 million in diabetes-related CHD costs avoided. Conclusions A reduction of SSB consumption could yield substantial population health benefits and cost savings for California. In particular, racial, ethnic, and low-income subgroups of California could reap the greatest health benefits. PMID:24349119

Autodisplay of the La/SSB protein on LPS-free E. coli for the diagnosis of Sjögren's syndrome.

PubMed

Yoo, Gu; Dilkaute, Carina; Bong, Ji-Hong; Song, Hyun-Woo; Lee, Misu; Kang, Min-Jung; Jose, Joachim; Pyun, Jae-Chul

2017-05-01

The objective of this study was to present an immunoassay for the diagnosis of Sjögren's syndrome based on the autodisplayed La/SSB protein on the outer membrane of intact E. coli (strain UT-5600) and LPS-free E. coli (ClearColi™). As the first step, an autodisplay vector (pCK002) was transfected into intact E. coli and LPS-free E. coli for comparison of efficiency of autdisplay of La/SSB. The maximal level of La/SSB expression was estimated to be similar for LPS-free E. coli and intact E. coli at different optimal induction periods. Intact E. coli was found to grow twofold faster than LPS-free E. coli, and the maximal level of expression for LPS-free E. coli was obtained with a longer induction period. When the zeta potential was measured, both intact E. coli and LPS-free E. coli showed negative values, and the autodisplay of negatively charged La/SSB protein (pI<7) on the outer membrane of intact E. coli and LPS-free E. coli resulted in a slight change in zeta potential values. E. coli with autodisplayed La/SSB protein was used for an immunoassay of anti-La/SSB antibodies for the diagnosis of Sjögren's syndrome. The surface of E. coli with the autodisplayed antigen was modified with rabbit serum and papain to prevent false positive signals because of nonspecific binding of unrelated antibodies from human serum. LPS-free E. coli with autodisplayed La/SSB protein yielded sensitivity and selectivity of 81.6% and 78.6%, respectively. The Bland-Altman test showed that the immunoassays based on LPS-free E. coli and intact E. coli with autodisplayed La/SSB protein were statistically equivalent to a clinical immunoassay for detection of anti-La/SSB antibodies (confidence coefficient 95%). Copyright © 2017 Elsevier Inc. All rights reserved.

Single-strand DNA-binding protein SSB1 facilitates TERT recruitment to telomeres and maintains telomere G-overhangs.

PubMed

Pandita, Raj K; Chow, Tracy T; Udayakumar, Durga; Bain, Amanda L; Cubeddu, Liza; Hunt, Clayton R; Shi, Wei; Horikoshi, Nobuo; Zhao, Yong; Wright, Woodring E; Khanna, Kum Kum; Shay, Jerry W; Pandita, Tej K

2015-03-01

Proliferating mammalian stem and cancer cells express telomerase [telomerase reverse transcriptase (TERT)] in an effort to extend chromosomal G-overhangs and maintain telomere ends. Telomerase-expressing cells also have higher levels of the single-stranded DNA-binding protein SSB1, which has a critical role in DNA double-strand break (DSB) repair. Here, we report that SSB1 binds specifically to G-strand telomeric DNA in vitro and associates with telomeres in vivo. SSB1 interacts with the TERT catalytic subunit and regulates its interaction with telomeres. Deletion of SSB1 reduces TERT interaction with telomeres and leads to G-overhang loss. Although SSB1 is recruited to DSB sites, we found no corresponding change in TERT levels at these sites, implying that SSB1-TERT interaction relies upon a specific chromatin structure or context. Our findings offer an explanation for how telomerase is recruited to telomeres to facilitate G-strand DNA extension, a critical step in maintaining telomere ends and cell viability in all cancer cells. Cancer Res; 75(5); 858-69. ©2015 AACR. ©2015 American Association for Cancer Research.

Single-photon-driven high-order sideband transitions in an ultrastrongly coupled circuit-quantum-electrodynamics system

NASA Astrophysics Data System (ADS)

Chen, Zhen; Wang, Yimin; Li, Tiefu; Tian, Lin; Qiu, Yueyin; Inomata, Kunihiro; Yoshihara, Fumiki; Han, Siyuan; Nori, Franco; Tsai, J. S.; You, J. Q.

2017-07-01

We report the experimental observation of high-order sideband transitions at the single-photon level in a quantum circuit system of a flux qubit ultrastrongly coupled to a coplanar waveguide resonator. With the coupling strength reaching 10% of the resonator's fundamental frequency, we obtain clear signatures of higher order red-sideband and first-order blue-sideband transitions, which are mainly due to the ultrastrong Rabi coupling. Our observation advances the understanding of ultrastrongly coupled systems and paves the way to study high-order processes in the quantum Rabi model at the single-photon level.

Identification of the divergent calmodulin binding motif in yeast Ssb1/Hsp75 protein and in other HSP70 family members.

PubMed

Heinen, R C; Diniz-Mendes, L; Silva, J T; Paschoalin, V M F

2006-11-01

Yeast soluble proteins were fractionated by calmodulin-agarose affinity chromatography and the Ca2+/calmodulin-binding proteins were analyzed by SDS-PAGE. One prominent protein of 66 kDa was excised from the gel, digested with trypsin and the masses of the resultant fragments were determined by MALDI/MS. Twenty-one of 38 monoisotopic peptide masses obtained after tryptic digestion were matched to the heat shock protein Ssb1/Hsp75, covering 37% of its sequence. Computational analysis of the primary structure of Ssb1/Hsp75 identified a unique potential amphipathic alpha-helix in its N-terminal ATPase domain with features of target regions for Ca2+/calmodulin binding. This region, which shares 89% similarity to the experimentally determined calmodulin-binding domain from mouse, Hsc70, is conserved in near half of the 113 members of the HSP70 family investigated, from yeast to plant and animals. Based on the sequence of this region, phylogenetic analysis grouped the HSP70s in three distinct branches. Two of them comprise the non-calmodulin binding Hsp70s BIP/GR78, a subfamily of eukaryotic HSP70 localized in the endoplasmic reticulum, and DnaK, a subfamily of prokaryotic HSP70. A third heterogeneous group is formed by eukaryotic cytosolic HSP70s containing the new calmodulin-binding motif and other cytosolic HSP70s whose sequences do not conform to those conserved motif, indicating that not all eukaryotic cytosolic Hsp70s are target for calmodulin regulation. Furthermore, the calmodulin-binding domain found in eukaryotic HSP70s is also the target for binding of Bag-1 - an enhancer of ADP/ATP exchange activity of Hsp70s. A model in which calmodulin displaces Bag-1 and modulates Ssb1/Hsp75 chaperone activity is discussed.

Projected Impact of Mexico’s Sugar-Sweetened Beverage Tax Policy on Diabetes and Cardiovascular Disease: A Modeling Study

PubMed Central

Sánchez-Romero, Luz Maria; Penko, Joanne; Coxson, Pamela G.; Fernández, Alicia; Mason, Antoinette; Moran, Andrew E.; Ávila-Burgos, Leticia; Barquera, Simón; Bibbins-Domingo, Kirsten

2016-01-01

Background Rates of diabetes in Mexico are among the highest worldwide. In 2014, Mexico instituted a nationwide tax on sugar-sweetened beverages (SSBs) in order to reduce the high level of SSB consumption, a preventable cause of diabetes and cardiovascular disease (CVD). We used an established computer simulation model of CVD and country-specific data on demographics, epidemiology, SSB consumption, and short-term changes in consumption following the SSB tax in order to project potential long-range health and economic impacts of SSB taxation in Mexico. Methods and Findings We used the Cardiovascular Disease Policy Model–Mexico, a state transition model of Mexican adults aged 35–94 y, to project the potential future effects of reduced SSB intake on diabetes incidence, CVD events, direct diabetes healthcare costs, and mortality over 10 y. Model inputs included short-term changes in SSB consumption in response to taxation (price elasticity) and data from government and market research surveys and public healthcare institutions. Two main scenarios were modeled: a 10% reduction in SSB consumption (corresponding to the reduction observed after tax implementation) and a 20% reduction in SSB consumption (possible with increases in taxation levels and/or additional measures to curb consumption). Given uncertainty about the degree to which Mexicans will replace calories from SSBs with calories from other sources, we evaluated a range of values for calorie compensation. We projected that a 10% reduction in SSB consumption with 39% calorie compensation among Mexican adults would result in about 189,300 (95% uncertainty interval [UI] 155,400–218,100) fewer incident type 2 diabetes cases, 20,400 fewer incident strokes and myocardial infarctions, and 18,900 fewer deaths occurring from 2013 to 2022. This scenario predicts that the SSB tax could save Mexico 983 million international dollars (95% UI $769 million–$1,173 million). The largest relative and absolute reductions in diabetes and CVD events occurred in the youngest age group modeled (35–44 y). This study’s strengths include the use of an established mathematical model of CVD and use of contemporary Mexican vital statistics, data from health surveys, healthcare costs, and SSB price elasticity estimates as well as probabilistic and deterministic sensitivity analyses to account for uncertainty. The limitations of the study include reliance on US-based studies for certain inputs where Mexico-specific data were lacking (specifically the associations between risk factors and CVD outcomes [from the Framingham Heart Study] and SSB calorie compensation assumptions), limited data on healthcare costs other than those related to diabetes, and lack of information on long-term SSB price elasticity that is specific to geographic and economic subgroups. Conclusions Mexico’s high diabetes prevalence represents a public health crisis. While the long-term impact of Mexico’s SSB tax is not yet known, these projections, based on observed consumption reductions, suggest that Mexico’s SSB tax may substantially decrease morbidity and mortality from diabetes and CVD while reducing healthcare costs. PMID:27802278

Preschoolers' influence on and help with beverage selection at the grocery store is linked to maternal responsiveness and child beverage intake: An exploratory study.

PubMed

Lora, Karina R; Hubbs-Tait, Laura; Guzman, Melissa; Wakefield, Dorothy; Sisson, Susan B; Mayeux, Lara

2016-12-01

Children's involvement in beverage selection or purchase has seldom been investigated. The responsiveness dimension of parental feeding styles has been related to healthy maternal feeding practices. Assessing mothers' reports of responsiveness and demandingness in grocery stores may shed light on influences on purchases of sugar-sweetened beverages (SSB) and fruit juice (FJ). Study objectives were to explore whether (1) maternal responsiveness and demandingness were associated with preschoolers' a) help with selection of and b) influence on SSB and FJ purchases during grocery shopping and whether (2) preschoolers' a) help with selection of and b) influence on SSB and FJ purchases were associated with child intake of these beverages. Mothers of 3-to-5-year-old children (n=185) who co-shopped with the child completed the Caregiver Feeding Style Questionnaire, reported frequency of child help with selection and influence on beverage purchase via questionnaire, and provided a one-day weekend food recall for the child. In adjusted logistic regressions, responsiveness was associated with child help selecting FJ (OR=6.50, 95% CI[1.04, 40.75], p<0.05), but not SSB. In multiple regressions, children who frequently helped select or influenced SSB purchases had higher SSB intake, b(SE)=3.63(1.40), t(176)=2.59, and b(SE)=3.18(1.25), t(176)=2.53, p<0.05. Mothers with higher responsiveness were more likely to let their preschoolers select FJ but not SSB during shopping. Children who frequently helped select or influenced SSB purchases had higher SSB intake than children who did so infrequently. Additional parenting behaviors associated with grocery shopping should be explored. Copyright © 2016 Elsevier Ltd. All rights reserved.

Adults Who Order Sugar-Sweetened Beverages: Sociodemographics and Meal Patterns at Fast Food Chains.

PubMed

Taksler, Glen B; Kiszko, Kamila; Abrams, Courtney; Elbel, Brian

2016-12-01

Approximately 30% of adults consume sugar-sweetened beverages (SSBs) daily, many at fast food restaurants. Researchers examined fast food purchases to better understand which consumers order SSBs, particularly large SSBs. Fast food customers in New York City and New Jersey provided receipts and participated in a survey during 2013-2014 (N=11,614). Logistic regression analyses predicted three outcomes: ordering no beverage or a non-SSB, a small/medium SSB, or a large SSB. Among respondents who ordered a beverage (n=3,775), additional analyses predicted number of beverage calories and odds of ordering an SSB. Covariates included demographic and behavioral factors. Respondents aged 18-29 years were 88% more likely to order a large SSB than a non-SSB or no beverage, as compared with respondents aged ≥50 years (p<0.001). Among respondents who purchased a beverage, respondents ordered more beverage calories with a large combination meal (+85.13 kcal, p=0.001) or if the restaurant had a large cup size >30 ounces (+36.07 kcal, p=0.001). Hispanic and Asian respondents were less likely to order a large SSB (AOR=0.49 and 0.52, respectively, both p≤0.026) than non-Hispanic white respondents. Odds of ordering a large SSB were higher for respondents who ate in the restaurant (AOR=1.66, p<0.001) or stated that they chose beverage based on price (AOR=2.02, p<0.001). Young adults and customers of restaurants with a larger cup size were more likely to purchase SSBs, and their beverage calories increased with meal size. Increased understanding of these factors is an important step toward limiting unhealthy SSB consumption. Copyright © 2016 American Journal of Preventive Medicine. Published by Elsevier Inc. All rights reserved.

Price elasticity of the demand for sugar sweetened beverages and soft drinks in Mexico.

PubMed

Colchero, M A; Salgado, J C; Unar-Munguía, M; Hernández-Ávila, M; Rivera-Dommarco, J A

2015-12-01

A large and growing body of scientific evidence demonstrates that sugar drinks are harmful to health. Intake of sugar-sweetened beverages (SSB) is a risk factor for obesity and type 2 diabetes. Mexico has one of the largest per capita consumption of soft drinks worldwide and high rates of obesity and diabetes. Fiscal approaches such as taxation have been recommended as a public health policy to reduce SSB consumption. We estimated an almost ideal demand system with linear approximation for beverages and high-energy food by simultaneous equations and derived the own and cross price elasticities for soft drinks and for all SSB (soft drinks, fruit juices, fruit drinks, flavored water and energy drinks). Models were stratified by income quintile and marginality index at the municipality level. Price elasticity for soft drinks was -1.06 and -1.16 for SSB, i.e., a 10% price increase was associated with a decrease in quantity consumed of soft drinks by 10.6% and 11.6% for SSB. A price increase in soft drinks is associated with larger quantity consumed of water, milk, snacks and sugar and a decrease in the consumption of other SSB, candies and traditional snacks. The same was found for SSB except that an increase in price of SSB was associated with a decrease in snacks. Higher elasticities were found among households living in rural areas (for soft drinks), in more marginalized areas and with lower income. Implementation of a tax to soft drinks or to SSB could decrease consumption particularly among the poor. Substitutions and complementarities with other food and beverages should be evaluated to assess the potential impact on total calories consumed. Copyright © 2015 The Authors. Published by Elsevier B.V. All rights reserved.

Adults Who Order Sugar-Sweetened Beverages

PubMed Central

Taksler, Glen B.; Kiszko, Kamila; Abrams, Courtney; Elbel, Brian

2016-01-01

Introduction Approximately 30% of adults consume sugar-sweetened beverages (SSBs) daily, many at fast food restaurants. Researchers examined fast food purchases to better understand which consumers order SSBs, particularly large SSBs. Methods Fast food customers in New York City and New Jersey provided receipts and participated in a survey during 2013–2014 (N=11,614). Logistic regression analyses predicted three outcomes: ordering no beverage or a non-SSB, a small/medium SSB, or a large SSB. Among respondents who ordered a beverage (n=3,775), additional analyses predicted number of beverage calories and odds of ordering an SSB. Covariates included demographic and behavioral factors. Results Respondents aged 18–29 years were 88% more likely to order a large SSB than a non-SSB or no beverage, as compared with respondents aged ≥50 years (p<0.001). Among respondents who purchased a beverage, respondents ordered more beverage calories with a large combination meal (+85.13 kcal, p=0.001) or if the restaurant had a large cup size >30 ounces (+36.07 kcal, p=0.001). Hispanic and Asian respondents were less likely to order a large SSB (AOR=0.49 and 0.52, respectively, both p≤0.026) than non-Hispanic white respondents. Odds of ordering a large SSB were higher for respondents who ate in the restaurant (AOR=1.66, p<0.001) or stated that they chose beverage based on price (AOR=2.02, p<0.001). Conclusions Young adults and customers of restaurants with a larger cup size were more likely to purchase SSBs, and their beverage calories increased with meal size. Increased understanding of these factors is an important step toward limiting unhealthy SSB consumption. PMID:27662697

Numerical Analysis of the Sea State Bias for Satellite Altimetry

NASA Technical Reports Server (NTRS)

Glazman, R. E.; Fabrikant, A.; Srokosz, M. A.

1996-01-01

Theoretical understanding of the dependence of sea state bias (SSB) on wind wave conditions has been achieved only for the case of a unidirectional wind-driven sea. Recent analysis of Geosat and TOPEX altimeter data showed that additional factors, such as swell, ocean currents, and complex directional properties of realistic wave fields, may influence SSB behavior. Here we investigate effects of two-dimensional multimodal wave spectra using a numerical model of radar reflection from a random, non-Gaussian surface. A recently proposed ocean wave spectrum is employed to describe sea surface statistics. The following findings appear to be of particular interest: (1) Sea swell has an appreciable effect in reducing the SSB coefficient compared with the pure wind sea case but has less effect on the actual SSB owing to the corresponding increase in significant wave height. (2) Hidden multimodal structure (the two-dimensional wavenumber spectrum contains separate peaks, for swell and wind seas, while the frequency spectrum looks unimodal) results in an appreciable change of SSB. (3) For unimodal, purely wind-driven seas, the influence of the angular spectral width is relatively unimportant; that is, a unidirectional sea provides a good qualitative model for SSB if the swell is absent. (4) The pseudo wave age is generally much better fo parametrization the SSB coefficient than the actual wave age (which is ill-defined for a multimodal sea) or wind speed. (5) SSB can be as high as 5% of the significant wave height, which is significantly greater than predicted by present empirical model functions tuned on global data sets. (6) Parameterization of SSB in terms of wind speed is likely to lead to errors due to the dependence on the (in practice, unknown) fetch.

Universal Stabilization of a Parametrically Coupled Qubit

NASA Astrophysics Data System (ADS)

Lu, Yao; Chakram, S.; Leung, N.; Earnest, N.; Naik, R. K.; Huang, Ziwen; Groszkowski, Peter; Kapit, Eliot; Koch, Jens; Schuster, David I.

2017-10-01

We autonomously stabilize arbitrary states of a qubit through parametric modulation of the coupling between a fixed frequency qubit and resonator. The coupling modulation is achieved with a tunable coupling design, in which the qubit and the resonator are connected in parallel to a superconducting quantum interference device. This allows for quasistatic tuning of the qubit-cavity coupling strength from 12 MHz to more than 300 MHz. Additionally, the coupling can be dynamically modulated, allowing for single-photon exchange in 6 ns. Qubit coherence times exceeding 20 μ s are maintained over the majority of the range of tuning, limited primarily by the Purcell effect. The parametric stabilization technique realized using the tunable coupler involves engineering the qubit bath through a combination of photon nonconserving sideband interactions realized by flux modulation, and direct qubit Rabi driving. We demonstrate that the qubit can be stabilized to arbitrary states on the Bloch sphere with a worst-case fidelity exceeding 80%.

Beverages Sales in Mexico before and after Implementation of a Sugar Sweetened Beverage Tax

PubMed Central

Colchero, M. A; Guerrero-López, Carlos Manuel; Molina, Mariana; Rivera, Juan Angel

2016-01-01

Objective To estimate changes in sales of sugar sweetened beverages (SSB) and plain water after a 1 peso per liter excise SSB tax was implemented in Mexico in January 2014. Material and Methods We used sales data from the Monthly Surveys of the Manufacturing Industry from January 2007 to December 2015. We estimated Ordinary Least Squares models to assess changes in per capita sales of SSB and plain water adjusting for seasonality and the global indicator of economic activity. Results We found a decrease of 7.3% in per capita sales of SSB and an increase of 5.2% of per capita sales of plain water in 2014–2015 compared to the pre-tax period (2007–2013). Conclusions Adjusting for variables that change over time and that are associated with the demand for SSB, we found the tax was associated with a reduction in per capita sales of SSB. The effectiveness of the tax should be evaluated in the medium and long term. PMID:27668875

Limiting the consumption of sugar sweetened beverages in Mexico's obesogenic environment: a qualitative policy review and stakeholder analysis.

PubMed

Moise, Nathalie; Cifuentes, Enrique; Orozco, Emanuel; Willett, Walter

2011-11-01

Mexico is building a legal framework to address its childhood obesity epidemic. Sugar sweetened beverages (SSB) in the school environment represent a major policy challenge. We addressed the following questions: What barriers inhibit political attention to SSB and childhood obesity? What political instruments, international and national, exist to guide agenda setting in Mexico? What opportunities exist for policy adoption? We conducted a systematic review of international and national legal instruments concerned with SSB consumption. We traced process, conducting interviews with key informants. Thematic analysis helped us identify barriers and opportunities for public health interventions. We found 11 national policy instruments, but detected implementation gaps and weak fiscal policies on SSB consumption in schools: limited drinking water infrastructure, SSB industry interests, and regulatory ambiguities addressing reduction of sugar in beverages. Public policy should target marketing practices and taxation. The school environment remains a promising target for policy. Access to safe drinking water must complement comprehensive and multi-sector policy approaches to reduce access to SSB.

Exploring the Theory of Planned Behavior to Explain Sugar-Sweetened Beverage Consumption

PubMed Central

Estabrooks, Paul; Davy, Brenda; Chen, Yvonnes; You, Wendy

2011-01-01

Objective To describe sugar-sweetened beverage (SSB) consumption, establish psychometric properties and utility of a Theory of Planned Behavior (TPB) instrument for SSB consumption. Methods This cross-sectional survey included 119 southwest Virginia participants. Respondents were majority female (66%), white (89%), ≤ high school education (79%), and averaged 41.4 (±13.5) years. A validated beverage questionnaire was used to measure SSB. Eleven TPB constructs were assessed with a 56-item instrument. Analyses included descriptive statistics, one-way ANOVAs, Cronbach alphas, and multiple regressions. Results Sugar-sweetened beverage intake averaged 457 (±430) kilocalories/day. The TPB model provided a moderate explanation of SSB intake (R2=0.38; F=13.10, P<0.01). Behavioral intentions had the strongest relationships with SSB consumption, followed by attitudes, perceived behavioral control, and subjective norms. The six belief constructs did not predict significant variance in the models. Conclusions and Implications Future efforts to comprehensively develop and implement interventions guided by the TPB hold promise for reducing SSB intake. PMID:22154130

Multichannel photonic Hilbert transformers based on complex modulated integrated Bragg gratings.

PubMed

Cheng, Rui; Chrostowski, Lukas

2018-03-01

Multichannel photonic Hilbert transformers (MPHTs) are reported. The devices are based on single compact spiral integrated Bragg gratings on silicon with coupling coefficients precisely modulated by the phase of each grating period. MPHTs with up to nine wavelength channels and a single-channel bandwidth of up to ∼625  GHz are achieved. The potential of the devices for multichannel single-sideband signal generation is suggested. The work offers a new possibility of utilizing wavelength as an extra degree of freedom in designing radio-frequency photonic signal processors. Such multichannel processors are expected to possess improved capacities and a potential to greatly benefit current widespread wavelength division multiplexed systems.

Widely tunable optical parametric oscillation in a Kerr microresonator.

PubMed

Sayson, Noel Lito B; Webb, Karen E; Coen, Stéphane; Erkintalo, Miro; Murdoch, Stuart G

2017-12-15

We report on the first experimental demonstration of widely tunable parametric sideband generation in a Kerr microresonator. Specifically, by pumping a silica microsphere in the normal dispersion regime, we achieve the generation of phase-matched four-wave mixing sidebands at large frequency detunings from the pump. Thanks to the role of higher-order dispersion in enabling phase matching, small variations of the pump wavelength translate into very large and controllable changes in the wavelengths of the generated sidebands: we experimentally demonstrate over 720 nm of tunability using a low-power continuous-wave pump laser in the C-band. We also derive simple theoretical predictions for the phase-matched sideband frequencies and discuss the predictions in light of the discrete cavity resonance frequencies. Our experimentally measured sideband wavelengths are in very good agreement with theoretical predictions obtained from our simple phase-matching analysis.

Food Purchasing Behaviors and Sugar-Sweetened Beverage Consumption among Canadian Secondary School Students in the COMPASS Study.

PubMed

Godin, Katelyn M; Chaurasia, Ashok; Hammond, David; Leatherdale, Scott T

2018-02-23

To examine whether several food purchasing behaviors (ie, sources of meals or snacks) are associated with adolescents' sugar-sweetened beverage (SSB) consumption and whether these associations vary by province. Cross-sectional observational study. Alberta and Ontario, Canada. Secondary school students from Alberta (n = 3,300) and Ontario (n = 37,999) participating in year 2 (2013-2014) of the Cannabis Use, Obesity, Mental Health, Physical Activity, Alcohol Use, Smoking, Sedentary Behavior (COMPASS) study. Participants' self-reported frequency of consuming 3 SSB types (soft drinks, sweetened coffees/teas, and energy drinks) in a typical week. Hierarchical Poisson regression analyses. Participants from Alberta had a significantly (P < .05) higher rate of consuming SSBs and purchasing meals or snacks from school food outlets compared with their Ontario counterparts. Most of the food purchasing behaviors were significantly (P < .05) and positively associated with greater rates of SSB consumption. Meal or snack purchases on weekends (vs weekdays) and from food outlets off school property (vs on school property) had a greater association with SSB consumption. Eating a home-packed lunch was protective against SSB consumption across models. Adolescents' food purchasing behaviors have a significant impact on their propensity for SSB consumption. These data demonstrate potentially important contexts for SSB consumption and have implications for possible settings and strategies for future interventions to reduce adolescents' SSB intake. Copyright © 2017 Society for Nutrition Education and Behavior. Published by Elsevier Inc. All rights reserved.

Decreased consumption of sugar-sweetened beverages improved selected biomarkers of chronic disease risk among US adults: 1999 to 2010.

PubMed

Hert, Kerrie A; Fisk, Paul S; Rhee, Yeong S; Brunt, Ardith R

2014-01-01

Consumption of sugar-sweetened beverages (SSBs) increased greatly from the late 1970s to the early part of this decade. Although recent data show that consumption of SSB may now be declining, consumption levels still remain much higher than recommended. Using data from the National Health and Nutrition Examination Survey, we assessed trends in intakes of SSB and levels of chronic disease biomarkers from 1999 to 2010 and examined the associations of SSB intake and biomarkers of chronic disease risk. We hypothesized that SSB intake will decrease and biomarkers of chronic disease risk will improve, therefore indicating that high intake of SSB is associated with greater chronic disease risk. Univariate analysis showed that from 1999 to 2010, SSB consumption decreased (P for trend = .0026), high-density lipoprotein increased (P for trend < .0001), low-density lipoprotein decreased (P for trend = .0007), and C-reactive protein decreased (P for trend = .0096). Using multivariate analysis, we showed that higher intakes of SSB were associated with lower high-density lipoprotein (P for trend < .0001), in an unadjusted model and all models with increasing numbers of covariates, and higher C-reactive protein (P for trend < .05), in an unadjusted model and in models with age, race/ethnicity, sex, education level, and poverty income ratio adjustments. We conclude that SSB consumption is associated with biomarkers of chronic disease risk, independent of demographic and lifestyle factors. © 2014.

Effects of an intervention aimed at reducing the intake of sugar-sweetened beverages in primary school children: a controlled trial

PubMed Central

2014-01-01

Background Since sugar-sweetened beverages (SSB) may contribute to the development of overweight in children, effective interventions to reduce their consumption are needed. Here we evaluated the effect of a combined school- and community-based intervention aimed at reducing children’s SSB consumption by promoting the intake of water. Favourable intervention effects on children’s SSB consumption were hypothesized. Methods In 2011-2012, a controlled trial was conducted among four primary schools, comprising 1288 children aged 6-12 years who lived in multi-ethnic, socially deprived neighbourhoods in Rotterdam, the Netherlands. Intervention schools adopted the ‘water campaign’, an intervention developed using social marketing. Control schools continued with their regular health promotion programme. Primary outcome was children’s SSB consumption, measured using parent and child questionnaires and through observations at school, both at baseline and after one year of intervention. Results Significant positive intervention effects were found for average SSB consumption (B -0.19 litres, 95% CI -0.28;-0.10; parent report), average SSB servings (B -0.54 servings, 95% CI -0.82;-0.26; parent report) and bringing SSB to school (OR 0.51, 95% CI 0.36;0.72; observation report). Conclusions This study supports the effectiveness of the water campaign intervention in reducing children’s SSB consumption. Further studies are needed to replicate our findings. Trial registration Current Controlled Trials: NTR3400 PMID:25060113

The Effect of Price and Socio-Economic Level on the Consumption of Sugar-Sweetened Beverages (SSB): The Case of Ecuador.

PubMed

Paraje, Guillermo

2016-01-01

The objective of this article is to estimate the own-price, cross-price and income elasticities of demand for SSB in Ecuador, as an indispensable step for predicting a reduction in the consumption of said beverages caused by the potential implementation of taxes in Ecuador. In addition, the own-price, cross-price and income elasticities of sugar-free substitutes like mineral water and diet soft drinks and juices are also estimated. The data from the 2011-2012 ENIGHUR, which contains detailed information on household consumption and socioeconomic variables, was used. The estimates are done using Deaton's Almost Ideal Demand System (AIDS) which accounts for differences in the quality of goods purchased. This demand system is estimated for different socio-economic groups, according to total household expenditure. The results reveal own-price elasticities for SSB between -1.17 and -1.33 depending on the socio-economic group, in line with the existing evidence for developed countries. Own-price elasticity for non-SSB is between -1 and -1.24. Income elasticities reveal that both SSB and non-SSB are normal goods with elasticities decreasing for higher socio-economic groups. These results show that the consumption of SSB is sensitive to price changes, meaning that the implementation of taxes on said beverages could be effective in reducing their consumption. The fact that non-SSB are also sensitive to price changes would indicate that subsidies could be implemented for the production of some of them.

Sjögren Syndrome Antigen B (SSB)/La Promotes Global MicroRNA Expression by Binding MicroRNA Precursors through Stem-Loop Recognition*

PubMed Central

Liang, Chunyang; Xiong, Ke; Szulwach, Keith E.; Zhang, Yi; Wang, Zhaohui; Peng, Junmin; Fu, Mingui; Jin, Peng; Suzuki, Hiroshi I.; Liu, Qinghua

2013-01-01

MicroRNAs (miRNA) control numerous physiological and pathological processes. Typically, the primary miRNA (pri-miRNA) transcripts are processed by nuclear Drosha complex into ∼70-nucleotide stem-loop precursor miRNAs (pre-miRNA), which are further cleaved by cytoplasmic Dicer complex into ∼21-nucleotide mature miRNAs. However, it is unclear how nascent pre-miRNAs are protected from ribonucleases, such as MCPIP1, that degrade pre-miRNAs to abort miRNA production. Here, we identify Sjögren syndrome antigen B (SSB)/La as a pre-miRNA-binding protein that regulates miRNA processing in vitro. All three RNA-binding motifs (LAM, RRM1, and RRM2) of La/SSB are required for efficient pre-miRNA binding. Intriguingly, La/SSB recognizes the characteristic stem-loop structure of pre-miRNAs, of which the majority lack a 3′ UUU terminus. Moreover, La/SSB associates with endogenous pri-/pre-miRNAs and promotes miRNA biogenesis by stabilizing pre-miRNAs from nuclease (e.g. MCPIP1)-mediated decay in mammalian cells. Accordingly, we observed positive correlations between the expression status of La/SSB and Dicer in human cancer transcriptome and prognosis. These studies identify an important function of La/SSB as a global regulator of miRNA expression, and implicate stem-loop recognition as a major mechanism that mediates association between La/SSB and diverse RNA molecules. PMID:23129761

Sjogren syndrome antigen B (SSB)/La promotes global microRNA expression by binding microRNA precursors through stem-loop recognition.

PubMed

Liang, Chunyang; Xiong, Ke; Szulwach, Keith E; Zhang, Yi; Wang, Zhaohui; Peng, Junmin; Fu, Mingui; Jin, Peng; Suzuki, Hiroshi I; Liu, Qinghua

2013-01-04

MicroRNAs (miRNA) control numerous physiological and pathological processes. Typically, the primary miRNA (pri-miRNA) transcripts are processed by nuclear Drosha complex into ~70-nucleotide stem-loop precursor miRNAs (pre-miRNA), which are further cleaved by cytoplasmic Dicer complex into ~21-nucleotide mature miRNAs. However, it is unclear how nascent pre-miRNAs are protected from ribonucleases, such as MCPIP1, that degrade pre-miRNAs to abort miRNA production. Here, we identify Sjögren syndrome antigen B (SSB)/La as a pre-miRNA-binding protein that regulates miRNA processing in vitro. All three RNA-binding motifs (LAM, RRM1, and RRM2) of La/SSB are required for efficient pre-miRNA binding. Intriguingly, La/SSB recognizes the characteristic stem-loop structure of pre-miRNAs, of which the majority lack a 3' UUU terminus. Moreover, La/SSB associates with endogenous pri-/pre-miRNAs and promotes miRNA biogenesis by stabilizing pre-miRNAs from nuclease (e.g. MCPIP1)-mediated decay in mammalian cells. Accordingly, we observed positive correlations between the expression status of La/SSB and Dicer in human cancer transcriptome and prognosis. These studies identify an important function of La/SSB as a global regulator of miRNA expression, and implicate stem-loop recognition as a major mechanism that mediates association between La/SSB and diverse RNA molecules.

Isolating spectral cues in amplitude and quasi-frequency modulation discrimination by reducing stimulus duration.

PubMed

Borucki, Ewa; Berg, Bruce G

2017-05-01

This study investigated the psychophysical effects of distortion products in a listening task traditionally used to estimate the bandwidth of phase sensitivity. For a 2000 Hz carrier, estimates of modulation depth necessary to discriminate amplitude modulated (AM) tones and quasi-frequency modulated (QFM) were measured in a two interval forced choice task as a function modulation frequency. Temporal modulation transfer functions were often non-monotonic at modulation frequencies above 300 Hz. This was likely to be due to a spectral cue arising from the interaction of auditory distortion products and the lower sideband of the stimulus complex. When the stimulus duration was decreased from 200 ms to 20 ms, thresholds for low-frequency modulators rose to near-chance levels, whereas thresholds in the region of non-monotonicities were less affected. The decrease in stimulus duration appears to hinder the listener's ability to use temporal cues in order to discriminate between AM and QFM, whereas spectral information derived from distortion product cues appears more resilient. Copyright © 2017. Published by Elsevier B.V.

The 2-MM Range Receiving Module for Observations of Atmospheric Ozone Emission Line at 142.2 GHz

NASA Astrophysics Data System (ADS)

Piddyachiy, V. I.; Korolev, O. M.; Myshenko, V. V.; Shulga, V. M.

2015-09-01

A low-noise uncooled receiver was designed and constructed for measurements of the atmospheric ozone spectral line at 142.2 GHz. The design has shown the double-sideband (DSB) receiver noise temperature of about 350 K within 130 to 150 GHz. Critical construction features of the basic units (mixer, intermediate frequency amplifier, and diplexer) are described. Noise characteristics showed by the receiver are the best in the class of uncooled heterodyne receivers of the 2-mm wavelengths.

Automated rejection of parasitic frequency sidebands in heterodyne-detection LIDAR applications

NASA Technical Reports Server (NTRS)

Esproles, Carlos; Tratt, David M.; Menzies, Robert T.

1989-01-01

A technique is described for the detection of the sporadic onset of multiaxial mode behavior of a normally single-mode TEA CO2 laser. The technique is implemented using primarily commercial circuit modules; it incorporates a peak detector that displays the RF detector output on a digital voltmeter, and a LED bar graph. The technique was successfully demonstrated with an existing coherent atmospheric LIDAR facility utilizing an injection-seeded single-mode TEA CO2 laser. The block schematic diagram is included.

The Sunset Supply Base: Long Term COTS Supportability, Implementing Affordable Methods and Processes

DTIC Science & Technology

2003-03-01

7 D. BENEFITS OF THE SSB SYSTEM...69 Table 11: Summary of SSB Financial and Non-Financial Benefits ................................. 73 Table 12: Alignment with...SSB Specific Goals to Derived Benefits ................................ 74 xi THIS PAGE INTENTIONALLY LEFT BLANK xii LIST OF ABBREVIATIONS AND

Bacillus subtilis DNA polymerases, PolC and DnaE, are required for both leading and lagging strand synthesis in SPP1 origin-dependent DNA replication

PubMed Central

Seco, Elena M.

2017-01-01

Abstract Firmicutes have two distinct replicative DNA polymerases, the PolC leading strand polymerase, and PolC and DnaE synthesizing the lagging strand. We have reconstituted in vitro Bacillus subtilis bacteriophage SPP1 θ-type DNA replication, which initiates unidirectionally at oriL. With this system we show that DnaE is not only restricted to lagging strand synthesis as previously suggested. DnaG primase and DnaE polymerase are required for initiation of DNA replication on both strands. DnaE and DnaG synthesize in concert a hybrid RNA/DNA ‘initiation primer’ on both leading and lagging strands at the SPP1 oriL region, as it does the eukaryotic Pol α complex. DnaE, as a RNA-primed DNA polymerase, extends this initial primer in a reaction modulated by DnaG and one single-strand binding protein (SSB, SsbA or G36P), and hands off the initiation primer to PolC, a DNA-primed DNA polymerase. Then, PolC, stimulated by DnaG and the SSBs, performs the bulk of DNA chain elongation at both leading and lagging strands. Overall, these modulations by the SSBs and DnaG may contribute to the mechanism of polymerase switch at Firmicutes replisomes. PMID:28575448

Nuclear shieldings with the SSB-D functional.

PubMed

Armangué, Lluís; Solà, Miquel; Swart, Marcel

2011-02-24

The recently reported SSB-D functional [J. Chem. Phys. 2009, 131, 094103] is used to check the performance for obtaining nuclear magnetic resonance (NMR) shielding constants. Four different databases were studied, which contain a diversity of molecules and nuclear shielding constants. The SSB-D functional is compared with its "parent" functionals (PBE, OPBE), the KT2 functional that was designed specially for NMR applications and the coupled cluster CCSD(T) method. The best performance for the experimentally most-used elements ((1)H, (13)C) is obtained for the SSB-D and KT2 functionals.

Taxing sugar-sweetened beverages: not a "holy grail" but a cup at least half comment on "food taxes: a new holy grail?".

PubMed

Block, Jason P; Willett, Walter C

2013-08-01

In this commentary, we argue for the implementation of a sugar-sweetened beverage (SSB) tax as a tool to help address the global obesity and diabetes epidemics. Consumption of SSBs has increased exponentially over the last several decades, a trend that has been an important contributor to the obesity and diabetes epidemics. Prior evidence demonstrates that a SSB tax will likely decrease SSB consumption without significantly increasing consumption of other unhealthy food or beverages. Further, this tax is unlikely to have effects on income inequality and should not contribute to weight-based discrimination. A SSB tax also should raise revenue for government entities that already pay, through health care expenditures and health programs, for the consequences of excess SSB consumption.

Effects of Social Norms Information and Self-Affirmation on Sugar-Sweetened Beverage Consumption Intentions and Behaviors

PubMed Central

Rosas, Carlos E.; Gregorio-Pascual, Petrona; Driver, Redd; Martinez, Alyssa; Price, Stephanie L.; Lopez, Cristal; Mahler, Heike I. M.

2017-01-01

The separate and combined efficacy of a social norms and a self-affirmation intervention to motivate decreased sugar-sweetened beverage (SSB) consumption was examined in two experiments. College students were randomly assigned to receive information about SSB consumption risks, norms, both, or neither. In addition, participants performed either a self-affirmation or control task. Self-affirmation only weakly affected SSB consumption intentions and behaviors. However, participants in Experiment 2 who received risks information, norms information, or both reported greater SSB reduction intentions than did those who received no information. Two-weeks later, those who received both types of information reported more frequent behavior change preparations, and it appears this effect may have been partially mediated by the changes in intentions to reduce SSB consumption. PMID:29398745

The Potential for Spatial Distribution Indices to Signal Thresholds in Marine Fish Biomass

PubMed Central

Reuchlin-Hugenholtz, Emilie

2015-01-01

The frequently observed positive relationship between fish population abundance and spatial distribution suggests that changes in distribution can be indicative of trends in abundance. If contractions in spatial distribution precede declines in spawning stock biomass (SSB), spatial distribution reference points could complement the SSB reference points that are commonly used in marine conservation biology and fisheries management. When relevant spatial distribution information is integrated into fisheries management and recovery plans, risks and uncertainties associated with a plan based solely on the SSB criterion would be reduced. To assess the added value of spatial distribution data, we examine the relationship between SSB and four metrics of spatial distribution intended to reflect changes in population range, concentration, and density for 10 demersal populations (9 species) inhabiting the Scotian Shelf, Northwest Atlantic. Our primary purpose is to assess their potential to serve as indices of SSB, using fisheries independent survey data. We find that metrics of density offer the best correlate of spawner biomass. A decline in the frequency of encountering high density areas is associated with, and in a few cases preceded by, rapid declines in SSB in 6 of 10 populations. Density-based indices have considerable potential to serve both as an indicator of SSB and as spatially based reference points in fisheries management. PMID:25789624

Cluster-based single-sink wireless sensor networks and passive optical network converged network incorporating sideband modulation schemes

NASA Astrophysics Data System (ADS)

Kumar, Love; Sharma, Vishal; Singh, Amarpal

2018-02-01

Wireless sensor networks have tremendous applications, such as civil, military, and environmental monitoring. In most of the applications, sensor data are required to be propagated over the internet/core networks, which result in backhaul setback. Subsequently, there is a necessity to backhaul the sensed information of such networks together with prolonging of the transmission link. Passive optical network (PON) is next-generation access technology emerging as a potential candidate for convergence of the sensed data to the core system. Earlier, the work with single-optical line terminal-PON was demonstrated and investigated merely analytically. This work is an attempt to demonstrate a practical model of a bidirectional single-sink wireless sensor network-PON converged network in which the collected data from cluster heads are transmitted over PON networks. Further, modeled converged structure has been investigated under the influence of double, single, and tandem sideband modulation schemes incorporating a corresponding phase-delay to the sensor data entities that have been overlooked in the past. The outcome illustrates the successful fusion of the sensor data entities over PON with acceptable bit error rate and signal to noise ratio serving as a potential development in the sphere of such converged networks. It has also been revealed that the data entities treated with tandem side band modulation scheme help in improving the performance of the converged structure. Additionally, analysis for uplink transmission reported with queue theory in terms of time cycle, average time delay, data packet generation, and bandwidth utilization. An analytical analysis of proposed converged network shows that average time delay for data packet transmission is less as compared with time cycle delay.

All-optical single-sideband frequency upconversion utilizing the XPM effect in an SOA-MZI.

PubMed

Kim, Doo-Ho; Lee, Joo-Young; Choi, Hyung-June; Song, Jong-In

2016-09-05

An all-optical single sideband (OSSB) frequency upconverter based on the cross-phase modulation (XPM) effect is proposed and experimentally demonstrated to overcome the power fading problem caused by the chromatic dispersion of fiber in radio-over-fiber systems. The OSSB frequency upconverter consists of an arrayed waveguide grating (AWG) and a semiconductor optical amplifier Mach-Zehnder interferometer (SOA-MZI) and does not require an extra delay line used for phase noise compensation. The generated OSSB radio frequency (RF) signal transmitted over single-mode fibers up to 20 km shows a flat electrical RF power response as a function of the fiber length. The upconverted electrical RF signal at 48 GHz shows negligible degradation of the phase noise even without an extra delay line. The measured phase noise of the upconverted RF signal (48 GHz) is -74.72 dBc/Hz at an offset frequency of 10 kHz. The spurious free dynamic range (SFDR) measured by a two-tone test to estimate the linearity of the OSSB frequency upconverter is 72.5 dB·Hz^2/3.

Facile design and stabilization of a novel one-dimensional silicon-based photonic crystal microcavity

NASA Astrophysics Data System (ADS)

Salem, Mohamed Shaker; Ibrahim, Shaimaa Moustafa; Amin, Mohamed

2017-07-01

A novel silicon-based optical microcavity composed of a defect layer sandwiched between two parallel rugate mirrors is created by the electrochemical anodization of silicon in a hydrofluoric acid-based electrolyte using a precisely controlled current density profile. The profile consists of two sinusoidally modulated current waveforms separated by a fixed current that is applied to produce a defect layer between the mirrors. The spectral response of the rugate-based microcavity is simulated using the transfer matrix method and compared to the conventional Bragg-based microcavity. It is found that the resonance position of both microcavities is unchanged. However, the rugate-based microcavity exhibits a distinct reduction of the sidebands' intensity. Further attenuation of the sidebands' intensity is obtained by creating refractive index matching layers with optimized thickness at the bottom and top of the rugate-based microcavity. In order to stabilize the produced microcavity against natural oxidation, atomic layer deposition of an ultra-thin titanium dioxide layer on the pore wall is carried out followed by thermal annealing. The microcavity resonance position shows an observable sensitivity to the deposition and annealing processes.

On chip frequency comb: Characterization and optical arbitrary waveform generation

NASA Astrophysics Data System (ADS)

Ferdous, Fahmida

Recently, on-chip comb generation methods based on nonlinear optical modulation in ultrahigh quality factor monolithic micro-resonators have been demonstrated. In these methods, two pump photons are transformed into sideband photons in a four wave mixing process mediated by the Kerr nonlinearity. The essential advantages of these methods are simplicity, small size, very high repetition rates and sometimes CMOS compatibility. We investigate line-by-line pulse shaping of such combs generated in silicon nitride ring resonators. We demonstrate a simple example of optical arbitrary waveform generation (OAWG) from Kerr comb. We observe two distinct paths to comb formation which exhibit strikingly different time domain behaviors. For combs formed as a cascade of sidebands spaced by a single free spectral range (FSR) that spread from the pump, we are able to compress to nearly bandwidth limited pulses. This indicates high coherence across the spectra and provides new data on the high passive stability of the spectral phase. For combs where the initial sidebands are spaced by multiple FSRs which then fill in to give combs with single FSR spacing, the time domain data reveal partially coherent behavior. We also investigate the behaviors of a few sub-families of the partially coherent combs selected by a pulse shaper. We observe different coherence properties for different groups of comb lines. Furthermore we will discuss an ultrafast characterization techniques called dual comb electric eld cross correlation. This linear technique will provide both low optical power and broader bandwidth capability for full time domain characterization of OAWG from Kerr comb.

Participation of Bell Telephone Laboratories in Project Echo and Experimental Results

NASA Technical Reports Server (NTRS)

Jakes, William C., Jr.

1961-01-01

On August 12, 1960, Echo I, a 100-foot-diameter spherical balloon, was placed in orbit around the earth by the National Aeronautics and Space Administration. The objective was to demonstrate the feasibility of long-distance communication by microwave reflection from a satellite. A two-way coast-to-coast voice circuit was to be established between the Jet Propulsion Laboratory (JPL) facility in California and a station provided by Bell Telephone Laboratories (STL) in New Jersey. Similar tests were also planned with the Naval Research Laboratory and other stations. This paper describes the general organization and operation of the Holmdel, New Jersey, station, and discusses the results of the experiments performed between the balloon launching and March 1, 1961. Successful voice communication was achieved through a variety of modulation methods including frequency modulation with feedback, amplitude modulation, single-sideband modulation, and narrow-band phase modulation. Careful measurements were also made of the loss in the transmission path.

Beverage Choices of Adolescents and Their Parents Using the Theory of Planned Behavior: A Mixed Methods Analysis.

PubMed

Riebl, Shaun K; MacDougal, Carly; Hill, Catelyn; Estabrooks, Paul A; Dunsmore, Julie C; Savla, Jyoti; Frisard, Madlyn I; Dietrich, Andrea M; Davy, Brenda M

2016-02-01

Added sugar intake in the form of sugar-sweetened beverages (SSBs) has been considered a contributor to weight gain and cardiometabolic dysfunction in adults and youth. Adolescents are some of the highest consumers of added sugars, taking in ∼16% of their total calories from added sugars with ∼40% of these calories coming from SSBs. Food preferences and self-regulation of dietary intake by youth can be influenced by parents. To evaluate the effectiveness of the Theory of Planned Behavior (TPB) in understanding and predicting adolescents' SSB consumption, identify which constructs are the most important when evaluating SSB consumption in adolescents, and determine whether and how adolescents' beverage choices are influenced by parents' reactions to their beverage choices. Measurements for this cross-sectional study included four record-assisted 24-hour dietary recalls and responses to an SSB-specific TPB questionnaire from 100 adolescents. Consenting parents completed a beverage intake questionnaire, a TPB questionnaire, and the Parent Response to Beverage Choice Questionnaire. The TPB explained 34% of the variance in adolescents' and parents' intention to limit SSBs to <1cup/day. Parents' perceived behavioral control (b=1.35; P=0.002) and adolescents' subjective norms (b=0.57; P=0.001) were the strongest predictors of intention, and intention was the strongest predictor of SSB consumption in both adolescents and parents (b=-37 [P=0.026] and b=-49 [P=0.003], respectively). The TPB explained more variance in parent SSB consumption (R(2)=0.38) than adolescents (R(2)=0.22). Parents did more discouraging of SSBs and encouraging of non-SSBs. Adolescents' intention to limit SSB consumption moderated the relationship between parents' reactions encouraging SSBs and adolescents' predicted SSB consumption (P=0.021). The TPB explained a small but significant amount of variance in adolescents' SSB consumption. When addressing adolescent SSB intake, people in addition to parents may influence their intentions and SSB consumption. Copyright © 2016 Academy of Nutrition and Dietetics. Published by Elsevier Inc. All rights reserved.

Radio-frequency-modulated Rydberg states in a vapor cell

NASA Astrophysics Data System (ADS)

Miller, S. A.; Anderson, D. A.; Raithel, G.

2016-05-01

We measure strong radio-frequency (RF) electric fields using rubidium Rydberg atoms prepared in a room-temperature vapor cell as field sensors. Electromagnetically induced transparency is employed as an optical readout. We RF-modulate the 60{{{S}}}1/2 and 58{{{D}}}5/2 Rydberg states with 50 and 100 MHz fields, respectively. For weak to moderate RF fields, the Rydberg levels become Stark-shifted, and sidebands appear at even multiples of the driving frequency. In high fields, the adjacent hydrogenic manifold begins to intersect the shifted levels, providing rich spectroscopic structure suitable for precision field measurements. A quantitative description of strong-field level modulation and mixing of S and D states with hydrogenic states is provided by Floquet theory. Additionally, we estimate the shielding of DC electric fields in the interior of the glass vapor cell.

Risk associations of obesity with sugar-sweetened beverages and lifestyle factors in Chinese: the 'Better Health for Better Hong Kong' health promotion campaign.

PubMed

Ko, G T; So, W-y; Chow, C-c; Wong, P T; Tong, S D; Hui, S S; Kwok, R; Chan, A; Chan, C L; Chan, J C

2010-12-01

Excessive consumption of sugar-sweetened beverages (SSBs) increases risk of obesity. Similar data are lacking in Chinese populations with rapid nutritional transition. We aimed to examine the association between SSB intake, lifestyle factors and obesity in Hong Kong Chinese. This is a cross-sectional survey on SSB intake with 2295 (49.6%) men and 2334 (50.4%) women (age: median 43.0 years, range 18-81 years). They were recruited from a territory-wide health promotion campaign in Hong Kong. All subjects completed a questionnaire and underwent simple health tests. Their SSB intake was based on a 1-week recall (1 unit of SSB=250 ml, frequent SSB consumption=daily intake ≥2 units). Men were more likely than women to smoke, drink alcohol, frequently consumed SSB (20.5 vs 9.5%) and ate more meat portions (2.32±0.57 vs 2.15±0.44) but were physically more active (no exercise: 31.2 vs 39.2%) (P-values: all <0.001). After adjusting for confounding factors, frequent SSB intake remained independently associated with obesity in women (odds ratio (95% confidence interval): 1.86 (1.36-2.55)) while physical inactivity (1.84 (1.41-2.39) for none vs regular), smoking (1.29 (1.05-1.58)) and high daily meat intake (2.15 (1.36, 3.42)) predicted obesity in men. In Chinese of working age, SSB consumption in women and physical inactivity, smoking and high meat intake in men were associated with obesity.

A systematic review of methods to assess intake of sugar-sweetened beverages among healthy European adults and children: a DEDIPAC (DEterminants of DIet and Physical Activity) study.

PubMed

Riordan, Fiona; Ryan, Kathleen; Perry, Ivan J; Schulze, Matthias B; Andersen, Lene Frost; Geelen, Anouk; Van't Veer, Pieter; Eussen, Simone; van Dongen, Martien; Wijckmans-Duysens, Nicole; Harrington, Janas M

2017-03-01

Research indicates that intake of sugar-sweetened beverages (SSB) may be associated with negative health consequences. However, differences between assessment methods can affect the comparability of intake data across studies. The current review aimed to identify methods used to assess SSB intake among children and adults in pan-European studies and to inform the development of the DEDIPAC (DEterminants of DIet and Physical Activity) toolbox of methods suitable for use in future European studies. A literature search was conducted using three electronic databases and by hand-searching reference lists. English-language studies of any design which assessed SSB consumption were included in the review. Studies involving two or more European countries were included in the review. Healthy, free-living children and adults. The review identified twenty-three pan-European studies which assessed intake of SSB. The FFQ was the most commonly used (n 24), followed by the 24 h recall (n 6) and diet records (n 1). There were several differences between the identified FFQ, including the definition of SSB used. In total, seven instruments that were tested for validity were selected as potentially suitable to assess SSB intake among adults (n 1), adolescents (n 3) and children (n 3). The current review highlights the need for instruments to use an agreed definition of SSB. Methods that were tested for validity and used in pan-European populations encompassing a range of countries were identified. These methods should be considered for use by future studies focused on evaluating consumption of SSB.

The Effect of Price and Socio-Economic Level on the Consumption of Sugar-Sweetened Beverages (SSB): The Case of Ecuador

PubMed Central

Paraje, Guillermo

2016-01-01

The objective of this article is to estimate the own-price, cross-price and income elasticities of demand for SSB in Ecuador, as an indispensable step for predicting a reduction in the consumption of said beverages caused by the potential implementation of taxes in Ecuador. In addition, the own-price, cross-price and income elasticities of sugar-free substitutes like mineral water and diet soft drinks and juices are also estimated. The data from the 2011–2012 ENIGHUR, which contains detailed information on household consumption and socioeconomic variables, was used. The estimates are done using Deaton’s Almost Ideal Demand System (AIDS) which accounts for differences in the quality of goods purchased. This demand system is estimated for different socio-economic groups, according to total household expenditure. The results reveal own-price elasticities for SSB between –1.17 and –1.33 depending on the socio-economic group, in line with the existing evidence for developed countries. Own-price elasticity for non-SSB is between -1 and -1.24. Income elasticities reveal that both SSB and non-SSB are normal goods with elasticities decreasing for higher socio-economic groups. These results show that the consumption of SSB is sensitive to price changes, meaning that the implementation of taxes on said beverages could be effective in reducing their consumption. The fact that non-SSB are also sensitive to price changes would indicate that subsidies could be implemented for the production of some of them. PMID:27028608

News Coverage of Sugar-Sweetened Beverage Taxes: Pro- and Antitax Arguments in Public Discourse

PubMed Central

Gollust, Sarah E.; Jarlenski, Marian P.; Nathanson, Ashley M.; Barry, Colleen L.

2013-01-01

Objectives. We examined news coverage of public debates about large taxes on sugar-sweetened beverages (SSBs) to illuminate how the news media frames the debate and to inform future efforts to promote obesity-related public policy. Methods. We conducted a quantitative content analysis in which we assessed how frequently 30 arguments supporting or opposing SSB taxes appeared in national news media and in news outlets serving jurisdictions where SSB taxes were proposed between January 2009 and June 2011. Results. News coverage included more discrete protax than antitax arguments on average. Supportive arguments about the health consequences and financial benefits of SSB taxes appeared most often. The most frequent opposing arguments focused on how SSB taxes would hurt the economy and how they constituted inappropriate governmental intrusion. Conclusions. News outlets that covered the debate on SSB taxes in their jurisdictions framed the issue in largely favorable ways. However, because these proposals have not gained passage, it is critical for SSB tax advocates to reach audiences not yet persuaded about the merits of this obesity prevention policy. PMID:23597354

hSSB1 phosphorylation is dynamically regulated by DNA-PK and PPP-family protein phosphatases.

PubMed

Ashton, Nicholas W; Paquet, Nicolas; Shirran, Sally L; Bolderson, Emma; Kariawasam, Ruvini; Touma, Christine; Fallahbaghery, Azadeh; Gamsjaeger, Roland; Cubeddu, Liza; Botting, Catherine; Pollock, Pamela M; O'Byrne, Kenneth J; Richard, Derek J

2017-06-01

The maintenance of genomic stability is essential for cellular viability and the prevention of diseases such as cancer. Human single-stranded DNA-binding protein 1 (hSSB1) is a protein with roles in the stabilisation and restart of stalled DNA replication forks, as well as in the repair of oxidative DNA lesions and double-strand DNA breaks. In the latter process, phosphorylation of threonine 117 by the ATM kinase is required for hSSB1 stability and efficient DNA repair. The regulation of hSSB1 in other DNA repair pathways has however remained unclear. Here we report that hSSB1 is also directly phosphorylated by DNA-PK at serine residue 134. While this modification is largely suppressed in undamaged cells by PPP-family protein phosphatases, S134 phosphorylation is enhanced following the disruption of replication forks and promotes cellular survival. Together, these data thereby represent a novel mechanism for hSSB1 regulation following the inhibition of replication. Copyright © 2017 The Authors. Published by Elsevier B.V. All rights reserved.

The nature of the force-induced conformation transition of dsDNA studied by using single molecule force spectroscopy.

PubMed

Liu, Ningning; Bu, Tianjia; Song, Yu; Zhang, Wei; Li, Jinjing; Zhang, Wenke; Shen, Jiacong; Li, Hongbin

2010-06-15

Single-stranded DNA binding proteins (SSB) interact with single-stranded DNA (ssDNA) specifically. Taking advantage of this character, we have employed Bacillus subtilis SSB protein to investigate the nature of force-induced conformation transition of double-stranded DNA (dsDNA) by using AFM-based single molecule force spectroscopy (SMFS) technique. Our results show that, when a dsDNA is stretched beyond its contour length, the dsDNA is partially melted, producing some ssDNA segments which can be captured by SSB proteins. We have also systematically investigated the effects of stretching length, waiting time, and salt concentration on the conformation transition of dsDNA and SSB-ssDNA interactions, respectively. Furthermore, the effect of proflavine, a DNA intercalator, on the SSB-DNA interactions has been investigated, and the results indicate that the proflavine-saturated dsDNA can be stabilized to the extent that the dsDNA will no longer melt into ssDNA under the mechanical force even up to 150 pN, and no SSB-DNA interactions are detectable.

The Ribosome-Bound Chaperones RAC and Ssb1/2p Are Required for Accurate Translation in Saccharomyces cerevisiae

PubMed Central

Rakwalska, Magdalena; Rospert, Sabine

2004-01-01

The chaperone homologs RAC (ribosome-associated complex) and Ssb1/2p are anchored to ribosomes; Ssb1/2p directly interacts with nascent polypeptides. The absence of RAC or Ssb1/2p results in a similar set of phenotypes, including hypersensitivity against the aminoglycoside paromomycin, which binds to the small ribosomal subunit and compromises the fidelity of translation. In order to understand this phenomenon we measured the frequency of translation termination and misincorporation in vivo and in vitro with a novel reporter system. Translational fidelity was impaired in the absence of functional RAC or Ssb1/2p, and the effect was further enhanced by paromomycin. The mutant strains suffered primarily from a defect in translation termination, while misincorporation was compromised to a lesser extent. Consistently, a low level of soluble translation termination factor Sup35p enhanced growth defects in the mutant strains. Based on the combined data we conclude that RAC and Ssb1/2p are crucial in maintaining translational fidelity beyond their postulated role as chaperones for nascent polypeptides. PMID:15456889

The ribosome-bound chaperones RAC and Ssb1/2p are required for accurate translation in Saccharomyces cerevisiae.

PubMed

Rakwalska, Magdalena; Rospert, Sabine

2004-10-01

The chaperone homologs RAC (ribosome-associated complex) and Ssb1/2p are anchored to ribosomes; Ssb1/2p directly interacts with nascent polypeptides. The absence of RAC or Ssb1/2p results in a similar set of phenotypes, including hypersensitivity against the aminoglycoside paromomycin, which binds to the small ribosomal subunit and compromises the fidelity of translation. In order to understand this phenomenon we measured the frequency of translation termination and misincorporation in vivo and in vitro with a novel reporter system. Translational fidelity was impaired in the absence of functional RAC or Ssb1/2p, and the effect was further enhanced by paromomycin. The mutant strains suffered primarily from a defect in translation termination, while misincorporation was compromised to a lesser extent. Consistently, a low level of soluble translation termination factor Sup35p enhanced growth defects in the mutant strains. Based on the combined data we conclude that RAC and Ssb1/2p are crucial in maintaining translational fidelity beyond their postulated role as chaperones for nascent polypeptides.

News coverage of sugar-sweetened beverage taxes: pro- and antitax arguments in public discourse.

PubMed

Niederdeppe, Jeff; Gollust, Sarah E; Jarlenski, Marian P; Nathanson, Ashley M; Barry, Colleen L

2013-06-01

We examined news coverage of public debates about large taxes on sugar-sweetened beverages (SSBs) to illuminate how the news media frames the debate and to inform future efforts to promote obesity-related public policy. We conducted a quantitative content analysis in which we assessed how frequently 30 arguments supporting or opposing SSB taxes appeared in national news media and in news outlets serving jurisdictions where SSB taxes were proposed between January 2009 and June 2011. News coverage included more discrete protax than antitax arguments on average. Supportive arguments about the health consequences and financial benefits of SSB taxes appeared most often. The most frequent opposing arguments focused on how SSB taxes would hurt the economy and how they constituted inappropriate governmental intrusion. News outlets that covered the debate on SSB taxes in their jurisdictions framed the issue in largely favorable ways. However, because these proposals have not gained passage, it is critical for SSB tax advocates to reach audiences not yet persuaded about the merits of this obesity prevention policy.

Patterns of sugar-sweetened beverage consumption amongst young people aged 13-15 years during the school day in Scotland.

PubMed

Hamilton, Laura Kate; Wills, Wendy J

2017-09-01

There is currently little research regarding sugar-sweetened beverage (SSB) consumption patterns of young people though adolescents are thought to be frequent consumers of these drinks. There is no research regarding the other foods and drinks consumed alongside SSBs by young people. The aim of this paper is to explore the patterns of SSB purchase and consumption amongst young people aged 13-15 years. A purchasing recall questionnaire (PRQ) was administered online in seven case study schools with 535 young people aged 13-15 years. Nutrient composition (kilocalories, fat, saturated fat, sodium and sugar) was also calculated for food/drink purchases. Chi-Square and Wilcoxon-Mann Whitney tests were conducted to examine patterns of SSB consumption and sugar/kilocalories consumption for SSB consumers and non-consumers. SSB consumers were significantly more likely to consume a drink at mid-morning break. Fewer consumed food at mid-morning break, ate food before school or ate food at lunchtime, but this was not statistically significant. A higher percentage of SSB consumers consumed 'unhealthy' food and drinks in comparison to young people who did not consume a SSB. Both median lunchtime sugar consumption (40.7 g vs 10.2 g) and median sugar as a percentage of Kcals (39% vs 14%) were significantly higher for SSB purchasers in comparison to non-purchasers. The analysis highlights that SSB purchasers consume significantly more sugar at lunchtime than non-purchasers. However, both purchasers and non-purchasers exceeded WHO (2015) recommendations that sugar consumption be halved to form no more than 5% of daily energy intake. This study provides new insights for public health stakeholders and schools. Multifaceted and inventive strategies relevant to young people will be required to achieve the new WHO recommendations. Copyright © 2017 Elsevier Ltd. All rights reserved.

Saturation of a toroidal Alfvén eigenmode due to enhanced damping of nonlinear sidebands

NASA Astrophysics Data System (ADS)

Todo, Y.; Berk, H. L.; Breizman, B. N.

2012-09-01

This paper examines nonlinear magneto-hydrodynamic effects on the energetic particle driven toroidal Alfvén eigenmode (TAE) for lower dissipation coefficients and with higher numerical resolution than in the previous simulations (Todo et al 2010 Nucl. Fusion 50 084016). The investigation is focused on a TAE mode with toroidal mode number n = 4. It is demonstrated that the mechanism of mode saturation involves generation of zonal (n = 0) and higher-n (n ⩾ 8) sidebands, and that the sidebands effectively increase the mode damping rate via continuum damping. The n = 0 sideband includes the zonal flow peaks at the TAE gap locations. It is also found that the n = 0 poloidal flow represents a balance between the nonlinear driving force from the n = 4 components and the equilibrium plasma response to the n = 0 fluctuations. The spatial profile of the n = 8 sideband peaks at the n = 8 Alfvén continuum, indicating enhanced dissipation due to continuum damping.

Efficient Raman sideband cooling of trapped ions to their motional ground state

NASA Astrophysics Data System (ADS)

Che, H.; Deng, K.; Xu, Z. T.; Yuan, W. H.; Zhang, J.; Lu, Z. H.

2017-07-01

Efficient cooling of trapped ions is a prerequisite for various applications of the ions in precision spectroscopy, quantum information, and coherence control. Raman sideband cooling is an effective method to cool the ions to their motional ground state. We investigate both numerically and experimentally the optimization of Raman sideband cooling strategies and propose an efficient one, which can simplify the experimental setup as well as reduce the number of cooling pulses. Several cooling schemes are tested and compared through numerical simulations. The simulation result shows that the fixed-width pulses and varied-width pulses have almost the same efficiency for both the first-order and the second-order Raman sideband cooling. The optimized strategy is verified experimentally. A single 25Mg+ ion is trapped in a linear Paul trap and Raman sideband cooled, and the achieved average vibrational quantum numbers under different cooling strategies are evaluated. A good agreement between the experimental result and the simulation result is obtained.

Lack of findings for the association between obesity risk and usual sugar-sweetened beverage consumption in adults--a primary analysis of databases of CSFII-1989-1991, CSFII-1994-1998, NHANES III, and combined NHANES 1999-2002.

PubMed

Sun, Sam Z; Empie, Mark W

2007-08-01

The relationship between obesity risk and sugar-sweetened beverage (SSB) consumption was examined together with multiple lifestyle factors. Statistical analysis was performed using population dietary survey databases of USDA CSFII 1989-1991, CSFII 1994-1996, CDC NHANES III, and combined NHANES 1999-2002. Totally, 38,409 individuals, ages 20-74 years, with accompanying data of dietary intake, lifestyle factors, and anthropometrics were included in the descriptive statistics and risk analysis. Analytical results indicate that obesity risk was significantly and positively associated with gender, age, daily TV/screen watching hours and dietary fat content, and negatively associated with smoking habit, education and physical activity; obesity risk was not significantly associated with SSB consumption pattern, dietary saturated fat content and total calorie intake. No elevated BMI values or increased obesity rates were observed in populations frequently consuming SSB compared to populations infrequently consuming SSB. Additionally, one-day food consumption data was found to overestimate SSB usual intake by up to 38.9% compared to the data of multiple survey days. multiple lifestyle factors and higher dietary fat intake were significantly associated with obesity risk. Populations who frequently consumed SSB, primarily HFCS sweetened beverages, did not have a higher obesity rate or increased obesity risk than that of populations which consumed SSB infrequently.

Relation Between Sugar-Sweetened Beverage Consumption, Nutrition, and Lifestyle in a Military Population.

PubMed

Mullie, Patrick; Deliens, Tom; Clarys, Peter

2016-10-01

Objective to describe the demographic, socioeconomic, and nutritional behaviors associated with of sugar-sweetened beverage (SSB) consumption. cross-sectional. in January 2014, 26,566 military personnel, representing 84.6% of the 31,412 men and women in active service were invited to participate in an online survey. Included questions were about consumption of fruits and vegetables, meat, SSB, number of breakfasts a week, and military rank. 7,252 military subjects. mean (standard deviation) age of the participants was 45.4 (7.9) years for 6,529 males and 41.9 (8.9) years for 723 females. Mean (standard deviation) body mass index was 26.6 (3.6) kg/m 2 for males and 24.5 (3.9) kg/m 2 for females. The probability of consuming daily SSB decreased with age, and with increasing body mass index, being female, and being a noncommissioned officer or officer. Consumption of fruits and vegetables decreased for daily SSB consumption, but meat consumption increased. The odds ratio (95% confidence interval) for daily SSB consumption was 0.65 (0.58-0.74) for daily breakfast and 1.49 (1.30-1.71) for smoking. There was no relation between physical activity and SSB consumption. SSB consumption was associated with attributes of a lower quality diet. Reprint & Copyright © 2016 Association of Military Surgeons of the U.S.

Chemo-mechanical pushing of proteins along single-stranded DNA.

PubMed

Sokoloski, Joshua E; Kozlov, Alexander G; Galletto, Roberto; Lohman, Timothy M

2016-05-31

Single-stranded (ss)DNA binding (SSB) proteins bind with high affinity to ssDNA generated during DNA replication, recombination, and repair; however, these SSBs must eventually be displaced from or reorganized along the ssDNA. One potential mechanism for reorganization is for an ssDNA translocase (ATP-dependent motor) to push the SSB along ssDNA. Here we use single molecule total internal reflection fluorescence microscopy to detect such pushing events. When Cy5-labeled Escherichia coli (Ec) SSB is bound to surface-immobilized 3'-Cy3-labeled ssDNA, a fluctuating FRET signal is observed, consistent with random diffusion of SSB along the ssDNA. Addition of Saccharomyces cerevisiae Pif1, a 5' to 3' ssDNA translocase, results in the appearance of isolated, irregularly spaced saw-tooth FRET spikes only in the presence of ATP. These FRET spikes result from translocase-induced directional (5' to 3') pushing of the SSB toward the 3' ssDNA end, followed by displacement of the SSB from the DNA end. Similar ATP-dependent pushing events, but in the opposite (3' to 5') direction, are observed with EcRep and EcUvrD (both 3' to 5' ssDNA translocases). Simulations indicate that these events reflect active pushing by the translocase. The ability of translocases to chemo-mechanically push heterologous SSB proteins along ssDNA provides a potential mechanism for reorganization and clearance of tightly bound SSBs from ssDNA.

Need for specific sugar-sweetened beverage lessons for fourth- and fifth-graders.

PubMed

Bea, Jennifer W; Jacobs, Laurel; Waits, Juanita; Hartz, Vern; Martinez, Stephanie H; Standfast, Rebecca D; Farrell, Vanessa A; Bawden, Margine; Whitmer, Evelyn; Misner, Scottie

2015-01-01

Consumption of sugar-sweetened beverages (SSB) is linked to obesity. The authors hypothesized that school-based nutrition education would decrease SSB consumption. Self-selected interventional cohort with random selection for pre and post measurements. Arizona Supplemental Nutrition Assistance Program-Education Program-eligible schools. Randomly selected (9%) fourth- and fifth-grade classroom students. The University of Arizona Nutrition Network provided general nutrition education training and materials to teachers, to be delivered to their students. The University of Arizona Nutrition Network administered behavioral questionnaires to students in both fall and spring. Change in SSB consumption. Descriptive statistics were computed for student demographics and beverage consumption on the day before testing. Paired t tests evaluated change in classroom averages. Linear regression assessed potential correlates of SSB consumption. Fall mean SSB consumption was 1.1 (± 0.2) times; mean milk and water intake were 1.6 (± 0.2) and 5.2 (± 0.7) times, respectively. Beverage consumption increased (3.2%) in springtime, with increased SSBs (14.4%) accounting for the majority (P = .006). Change in SSB consumption was negatively associated with baseline SSB and water consumption but positively associated with baseline milk fat (P ≤ .05). The results suggest the need for beverage-specific education to encourage children to consume more healthful beverages in warmer weather. Copyright © 2015 Society for Nutrition Education and Behavior. Published by Elsevier Inc. All rights reserved.

A test of genetic models for the evolutionary maintenance of same-sex sexual behaviour.

PubMed

Hoskins, Jessica L; Ritchie, Michael G; Bailey, Nathan W

2015-06-22

The evolutionary maintenance of same-sex sexual behaviour (SSB) has received increasing attention because it is perceived to be an evolutionary paradox. The genetic basis of SSB is almost wholly unknown in non-human animals, though this is key to understanding its persistence. Recent theoretical work has yielded broadly applicable predictions centred on two genetic models for SSB: overdominance and sexual antagonism. Using Drosophila melanogaster, we assayed natural genetic variation for male SSB and empirically tested predictions about the mode of inheritance and fitness consequences of alleles influencing its expression. We screened 50 inbred lines derived from a wild population for male-male courtship and copulation behaviour, and examined crosses between the lines for evidence of overdominance and antagonistic fecundity selection. Consistent variation among lines revealed heritable genetic variation for SSB, but the nature of the genetic variation was complex. Phenotypic and fitness variation was consistent with expectations under overdominance, although predictions of the sexual antagonism model were also supported. We found an unexpected and strong paternal effect on the expression of SSB, suggesting possible Y-linkage of the trait. Our results inform evolutionary genetic mechanisms that might maintain low but persistently observed levels of male SSB in D. melanogaster, but highlight a need for broader taxonomic representation in studies of its evolutionary causes. © 2015 The Author(s) Published by the Royal Society. All rights reserved.

Bidirectional fiber-IVLLC and fiber-wireless convergence system with two orthogonally polarized optical sidebands.

PubMed

Lu, Hai-Han; Wu, Hsiao-Wen; Li, Chung-Yi; Ho, Chun-Ming; Yang, Zih-Yi; Cheng, Ming-Te; Lu, Chang-Kai

2017-05-01

A bidirectional fiber-invisible laser light communication (IVLLC) and fiber-wireless convergence system with two orthogonally polarized optical sidebands for hybrid cable television (CATV)/millimeter-wave (MMW)/baseband (BB) signal transmission is proposed and experimentally demonstrated. Two optical sidebands generated by a 60-GHz MMW signal are orthogonally polarized and separated into different polarizations. These orthogonally polarized optical sidebands are delivered over a 40-km single-mode fiber (SMF) transport to effectually reduce the fiber dispersion induced by a 40-km SMF transmission and the distortion caused by the parallel polarized optical sidebands. To the best of our knowledge, this work is the first to adopt two orthogonally polarized optical sidebands in a bidirectional fiber-IVLLC and fiber-wireless convergence system to reduce fiber dispersion and distortion effectually. Good carrier-to-noise ratio, composite second order, composite triple beat, and bit error rate (BER) are achieved for downlink transmission at a 40-km SMF operation and a 100-m free-space optical (FSO) link/3-m RF wireless transmission. For up-link transmission, good BER performance is acquired over a 40-km SMF transport and a 100-m FSO link. The approach presented in this work signifies the advancements in the convergence of SMF-based backbone and optical/RF wireless-based feeder.

Do soil microbes and abrasion by soil particles influence persistence and loss of physical dormancy in seeds of tropical pioneers?

USDA-ARS?s Scientific Manuscript database

Germination from the soil seed bank (SSB) is an important determinant of species composition in tropical forest gaps, with seed persistence in the SSB allowing plants to recruit several decades after seed dispersal. The capacity to form a persistent SSB is often associated with physical dormancy, wh...

Comparison of intracellular drug retention, DNA damage and cytotoxicity of derivatives of doxorubicin and daunorubicin in a human colon adenocarcinoma cell line (LoVo).

PubMed

Belvedere, G; Suarato, A; Geroni, C; Giuliani, F C; D'Incalci, M

1989-11-01

Formation of DNA single strand breaks (SSB) was assayed by alkaline elution in LoVo cells treated with doxorubicin, daunorubicin and six derivatives of these drugs modified either in the chromophore or the sugar. Seven compounds showed a biphasic relationship (initial increase and then a decrease) for the formation of DNA-SSB over the concentration range 0.05-10 micrograms/ml. At a drug concentration in the range causing an increase of DNA damage very fast repair of DNA-SSB was observed for 4'-deoxydoxorubicin and 4-demethoxydaunorubicin; the kinetics of DNA-SSB investigated after drug removal at a drug concentration reducing DNA-SSB showed a time dependent increase of DNA damage for both drugs although with different patterns. 4'-Deoxydoxorubicin reduced the effect of radiations on the rate of elution of DNA in a way resembling the formation of DNA interstrand cross links (ISC) at concentrations at which DNA-SSB were reduced. DNA-ISC were not produced by chemical reactions occurring during sample processing for alkaline elution and this derivative was not metabolized by LoVo cells. The IC50 of the anthracyclines were on a several log range, though for most of the derivatives the cytotoxicity curve showed a plateau at growth inhibition of about 15-30% at increasing intracellular drug levels. A relationship between DNA damage and cytotoxicity was observed only in a very small range of DNA-SSB. It is likely that the different effects of these anthracyclines on the formation of DNA-SSB depend on a qualitatively different interaction between drug-DNA and topoisomerase II when the drug concentration is raised.

The Reg1-interacting proteins, Bmh1, Bmh2, Ssb1, and Ssb2, have roles in maintaining glucose repression in Saccharomyces cerevisiae.

PubMed

Dombek, Kenneth M; Kacherovsky, Nataly; Young, Elton T

2004-09-10

In Saccharomyces cerevisiae, a type 1 protein phosphatase complex composed of the Glc7 catalytic subunit and the Reg1 regulatory subunit represses expression of many glucose-regulated genes. Here we show that the Reg1-interacting proteins Bmh1, Bmh2, Ssb1, and Ssb2 have roles in glucose repression. Deleting both BMH genes causes partially constitutive ADH2 expression without significantly increasing the level of Adr1 protein, the major activator of ADH2 expression. Adr1 and Bcy1, the regulatory subunit of cAMP-dependent protein kinase, are both required for this effect indicating that constitutive expression in Deltabmh1Deltabmh2 cells uses the same activation pathway that operates in Deltareg1 cells. Deletion of both BMH genes and REG1 causes a synergistic relief from repression, suggesting that Bmh proteins also act independently of Reg1 during glucose repression. A two-hybrid interaction with the Bmh proteins was mapped to amino acids 187-232, a region of Reg1 that is conserved in different classes of fungi. Deleting this region partially releases SUC2 from glucose repression. This indicates a role for the Reg1-Bmh interaction in glucose repression and also suggests a broad role for Bmh proteins in this process. An in vivo Reg1-Bmh interaction was confirmed by copurification of Bmh proteins with HA(3)-TAP-tagged Reg1. The nonconventional heat shock proteins Ssb1 and Ssb2 are also copurified with HA(3)-TAP-tagged Reg1. Deletion of both SSB genes modestly decreases repression of ADH2 expression in the presence of glucose, suggesting that Ssb proteins, perhaps through their interaction with Reg1, play a minor role in glucose repression.

Complementation of Saccharomyces cerevisiae mutations in genes involved in translation and protein folding (EFB1 and SSB1) with Candida albicans cloned genes.

PubMed

Maneu, V; Roig, P; Gozalbo, D

2000-11-01

We have demonstrated that the expression of Candida albicans genes involved in translation and protein folding (EFB1 and SSB1) complements the phenotype of Saccharomyces cerevisiae mutants. The elongation factor 1beta (EF-1beta) is essential for growth and efb1 S. cerevisiae null mutant cells are not viable; however, viable haploid cells, carrying the disrupted chromosomal allele of the S. cerevisiae EFB1 gene and pEFB1, were isolated upon sporulation of a diploid strain which was heterozygous at the EFB1 locus and transformed with pEFB1 (a pEMBLYe23 derivative plasmid containing an 8-kb DNA fragment from the C. albicans genome which contains the EFB1 gene). This indicates that the C. albicans EFB1 gene encodes a functional EF-1beta. Expression of the SSB1 gene from C. albicans, which codes for a member of the 70-kDa heat shock protein family, in S. cerevisiae ssb1 ssb2 double mutant complements the mutant phenotype (poor growth particularly at low temperature, and sensitivity to certain protein synthesis inhibitors, such as paromomycin). This complementation indicates that C. albicans Ssbl may function as a molecular chaperone on the translating ribosomes, as described in S. cerevisiae. Northern blot analysis showed that SSB mRNA levels increased after mild cold shift (28 degrees C to 23 degrees C) and rapidly decreased after mild heat shift (from 28 degrees C to 37 degrees C, and particularly to 42 degrees C), indicating that SSB1 expression is regulated by temperature. Therefore, Ssb1 may be considered as a molecular chaperone whose pattern of expression is similar to that found in ribosomal proteins, according to its common role in translation.

A homogeneous and "off-on" fluorescence aptamer-based assay for chloramphenicol using vesicle quantum dot-gold colloid composite probes.

PubMed

Miao, Yang-Bao; Ren, Hong-Xia; Gan, Ning; Zhou, You; Cao, Yuting; Li, Tianhua; Chen, Yinji

2016-07-27

In this work, a novel homogeneous and signal "off-on" aptamer based fluorescence assay was successfully developed to detect chloramphenicol (CAP) residues in food based on the fluorescence resonance energy transfer (FRET). The vesicle nanotracer was prepared through labeling single stranded DNA binding protein (SSB) on limposome-CdSe/ZnS quantum dot (SSB/L-QD) complexes. It was worth mentioning that the signal tracer (SSB/L-QD) with vesicle shape, which was fabricated being encapsulated with a number of quantum dots and SSB. The nanotracer has excellent signal amplification effects. The vesicle composite probe was formed by combining aptamer labeled nano-gold (Au-Apt) and SSB/L-QD. Which based on SSB's specific affinity towards aptamer. This probe can't emit fluoresce which is in "off" state because the signal from SSB/L-QD as donor can be quenched by the Au-aptas acceptor. When CAP was added in the composite probe solution, the aptamer on the Au-Apt can be preferentially bounded with CAP then release from the composite probe, which can turn the "off" signal of SSB/L-QD tracer into "on" state. The assay indicates excellent linear response to CAP from 0.001 nM to 10 nM and detection limit down to 0.3 pM. The vesicle probes with size of 88 nm have strong signal amplification. Because a larger number of QDs can be labeled inside the double phosphorus lipid membrane. Besides, it was employed to detect CAP residues in the milk samples with results being agreed well with those from ELISA, verifying its accuracy and reliability. Copyright © 2016 Elsevier B.V. All rights reserved.

Expression, purification and biochemical characterization of a single-stranded DNA binding protein from Herbaspirillum seropedicae.

PubMed

Vernal, Javier; Serpa, Viviane I; Tavares, Carolina; Souza, Emanuel M; Pedrosa, Fábio O; Terenzi, Hernán

2007-05-01

An open reading frame encoding a protein similar in size and sequence to the Escherichia coli single-stranded DNA binding protein (SSB protein) was identified in the Herbaspirillum seropedicae genome. This open reading frame was cloned into the expression plasmid pET14b. The SSB protein from H. seropedicae, named Hs_SSB, was overexpressed in E. coli strain BL21(DE3) and purified to homogeneity. Mass spectrometry data confirmed the identity of this protein. The apparent molecular mass of the native Hs_SSB was estimated by gel filtration, suggesting that the native protein is a tetramer made up of four similar subunits. The purified protein binds to single-stranded DNA (ssDNA) in a similar manner to other SSB proteins. The production of this recombinant protein in good yield opens up the possibility of obtaining its 3D-structure and will help further investigations into DNA metabolism.

Is Sugar the new Tobacco? Insights from Laboratory Studies, Consumer Surveys and Public Health.

PubMed

Le Bodo, Yann; Paquette, Marie-Claude; Vallières, Maggie; Alméras, Natalie

2015-03-01

In the Americas, mean energy intake from added sugar exceeds recent World Health Organization recommendations for free sugars in the diet. As a leading contributor to this excess, sugar-sweetened beverage (SSB) overconsumption represents a risk for the population's health. This article provides an overview of clinical and epidemiological evidence, marketing practices, corporate influence and prevention strategies related to added sugar and SSB. For each aspect of this multidimensional profile, we briefly compare SSB to the case of tobacco pointing to similarities but also major differences. Tobacco control has demonstrated the effectiveness of long term multifaceted prevention strategies in multiple settings supported by strong public policies which may be applied to the consumption of SSB. However, translating these policies to the specific case of SSB is urgently needed, to inform preventive actions, decide which intervention mix will be used, and evaluate the process and impact of the chosen strategy.

RF Jitter Modulation Alignment Sensing

NASA Astrophysics Data System (ADS)

Ortega, L. F.; Fulda, P.; Diaz-Ortiz, M.; Perez Sanchez, G.; Ciani, G.; Voss, D.; Mueller, G.; Tanner, D. B.

2017-01-01

We will present the numerical and experimental results of a new alignment sensing scheme which can reduce the complexity of alignment sensing systems currently used, while maintaining the same shot noise limited sensitivity. This scheme relies on the ability of electro-optic beam deflectors to create angular modulation sidebands in radio frequency, and needs only a single-element photodiode and IQ demodulation to generate error signals for tilt and translation degrees of freedom in one dimension. It distances itself from current techniques by eliminating the need for beam centering servo systems, quadrant photodetectors and Gouy phase telescopes. RF Jitter alignment sensing can be used to reduce the complexity in the alignment systems of many laser optical experiments, including LIGO and the ALPS experiment.

Investigate optimum way of adding wideband capability and recommend a design for modification of one government furnished AM baseband demultiplexer, phase 1

NASA Technical Reports Server (NTRS)

1972-01-01

The effort to analyze and test the Teledyne/Adcom model G-146 demultiplexer to determine the feasibility and optimum method(s) for modifying the unit for broadband operation is described. The desired bandwidths under consideration included 2, 4, and 8 kHz for double sideband and quadrature double sideband, and 4, 8, and 16 kHz for single sideband.

Investigating Vibration Properties of a Planetary Gear Set with a Cracked Tooth in a Planet Gear

DTIC Science & Technology

2014-12-23

sidebands appear at mfm±nfplanet± kfc or mfm±nfplanet±kfp, where m, n and k are all integers; fp represents rotation frequency of the planet gear and...region from 43 fm to 45 fm. Sidebands are not symmetric and sizable sidebands located at mfm±nfplanet± kfc or mfm±nfplanet±kfp, where m, n and k are

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

Xiong, Hao, E-mail: haoxiong1217@gmail.com; Fan, Yu-Wan; Yang, Xiaoxue

We investigate radiation-pressure induced generation of the frequency components at the difference-sideband in an optomechanical system, which beyond the conventional linearized description of optomechanical interactions between cavity fields and the mechanical oscillation. We analytically calculate amplitudes of these signals, and identify a simple square-root law for both the upper and lower difference-sideband generation which can describe the dependence of the intensities of these signals on the pump power. Further calculation shows that difference-sideband generation can be greatly enhanced via achieving the matching conditions. The effect of difference-sideband generation, which may have potential application for manipulation of light, is especially suitedmore » for on-chip optomechanical devices, where nonlinear optomechanical interaction in the weak coupling regime is within current experimental reach.« less

Competing four-wave mixing processes in dispersion oscillating telecom fiber.

PubMed

Finot, Christophe; Fatome, Julien; Sysoliatin, Alexej; Kosolapov, A; Wabnitz, Stefan

2013-12-15

We experimentally study the dynamics of the generation of multiple sidebands by means of a quasi-phase-matched four-wave mixing (FWM) process occurring in a dispersion-oscillating, highly nonlinear optical fiber. The fiber under test is pumped by a ns microchip laser operating in the normal average group-velocity dispersion regime and in the telecom C band. We reveal that the growth of higher-order sidebands is strongly influenced by the competition with cascade FWM between the pump and the first-order quasi-phase matched sidebands. The properties of these competing FWM processes are substantially affected when a partially coherent pump source is used, leading to a drastic reduction of the average power needed for sideband generation.

Electrical power inverter having a phase modulated, twin-inverter, high frequency link and an energy storage module

DOEpatents

Pitel, Ira J.

1987-02-03

The present invention provides an electrical power inverter method and apparatus, which includes a high frequency link, for converting DC power into AC power. Generally stated, the apparatus includes a first high frequency module which produces an AC voltage at a first output frequency, and a second high frequency inverter module which produces an AC voltage at a second output frequency that is substantially the same as the first output frequency. The second AC voltage is out of phase with the first AC voltage by a selected angular phase displacement. A mixer mixes the first and second output voltages to produce a high frequency carrier which has a selected base frequency impressed on the sidebands thereof. A rectifier rectifies the carrier, and a filter filters the rectified carrier. An output inverter inverts the filtered carrier to produce an AC line voltage at the selected base frequency. A phase modulator adjusts the relative angular phase displacement between the outputs of the first and second high frequency modules to control the base frequency and magnitude of the AC line voltage.

Electrical power inverter having a phase modulated, twin-inverter, high frequency link and an energy storage module

DOEpatents

Pitel, I.J.

1987-02-03

The present invention provides an electrical power inverter method and apparatus, which includes a high frequency link, for converting DC power into AC power. Generally stated, the apparatus includes a first high frequency module which produces an AC voltage at a first output frequency, and a second high frequency inverter module which produces an AC voltage at a second output frequency that is substantially the same as the first output frequency. The second AC voltage is out of phase with the first AC voltage by a selected angular phase displacement. A mixer mixes the first and second output voltages to produce a high frequency carrier which has a selected base frequency impressed on the sidebands thereof. A rectifier rectifies the carrier, and a filter filters the rectified carrier. An output inverter inverts the filtered carrier to produce an AC line voltage at the selected base frequency. A phase modulator adjusts the relative angular phase displacement between the outputs of the first and second high frequency modules to control the base frequency and magnitude of the AC line voltage. 19 figs.

A simplified filterless photonic frequency octupling scheme based on cascaded modulators

NASA Astrophysics Data System (ADS)

Zhang, Wu; Wen, Aijun; Gao, Yongsheng; Zheng, Hanxiao; Chen, Wei; He, Hongye

2017-04-01

A simplified filterless frequency octupling scheme by connecting an intensity modulator (IM) with a dual-parallel Mach-Zehnder (DPMZM) in series is proposed in this paper. The LO signal is distributed into two parts, and one part is used to drive the IM and the other part is applied to drive the DPMZM's upper sub-modulator, both at the peak point. The lower sub-modulator is only driven by dc bias, and the parent modulator works at null point. By properly adjusting dc bias of the lower sub-modulator, only ±4th-order optical sidebands dominate at the output of the DPMZM. The approach is verified by experiments, and 32-GHz and 40-GHz millimetre waves (mm-waves) are generated using 4-GHz and 5-GHz LO signals, respectively. We acquire a 15-dB electrical spurious suppression ratio (ESSR) and a relatively good phase noise of the signal. Compared with other schemes, the scheme is simple in configuration because only an IM and a DPMZM are needed. What's more, the scheme is tunable in frequency as no filter is used.

Exploring the theory of planned behavior to explain sugar-sweetened beverage consumption.

PubMed

Zoellner, Jamie; Estabrooks, Paul A; Davy, Brenda M; Chen, Yi-Chun Yvonnes; You, Wen

2012-01-01

To describe sugar-sweetened beverage (SSB) consumption and to establish psychometric properties and utility of a Theory of Planned Behavior (TPB) instrument for SSB consumption. This cross-sectional survey included 119 southwest Virginia participants. Most of the respondents were female (66%), white (89%), and had at least a high school education (79%), and their average age was 41.4 ± 13.5 years. A validated beverage questionnaire was used to measure SSB. Eleven TPB constructs were assessed with a 56-item instrument. Analyses included descriptive statistics, 1-way ANOVA, Cronbach α, and multiple regression. Sugar-sweetened beverage intake averaged 457 ± 430 kcal/d. The TPB model provided a moderate explanation of SSB intake (R(2) = 0.38; F = 13.10, P < .01). Behavioral intentions had the strongest relationships with SSB consumption, followed by attitudes, perceived behavioral control, and subjective norms. The 6 belief constructs did not predict significant variance in the models. Future efforts to comprehensively develop and implement interventions guided by the TPB hold promise for reducing SSB intake. Copyright © 2012 Society for Nutrition Education and Behavior. Published by Elsevier Inc. All rights reserved.

Trends in beverage prices following the introduction of a tax on sugar-sweetened beverages in Barbados.

PubMed

Alvarado, Miriam; Kostova, Deliana; Suhrcke, Marc; Hambleton, Ian; Hassell, Trevor; Samuels, T Alafia; Adams, Jean; Unwin, Nigel

2017-12-01

A 10% excise tax on sugar sweetened beverages (SSBs) was implemented in Barbados in September 2015. A national evaluation has been established to assess the impact of the tax. We present a descriptive analysis of initial price changes following implementation of the SSB tax using price data provided by a major supermarket chain in Barbados over the period 2014-2016. We summarize trends in price changes for SSBs and non-SSBs before and after the tax using year-on-year mean price per liter. We find that prior to the tax, the year-on-year growth of SSB and non-SSB prices was very similar (approximately 1%). During the quarter in which the tax was implemented, the trends diverged, with SSB price growth increasing to 3% and that of non-SSBs decreasing slightly. The growth of SSB prices outpaced non-SSBs prices in each quarter thereafter, reaching 5.9% compared to <1% for non-SSBs. Future analyses will assess the trends in prices of SSBs and non-SSBs over a longer period and will integrate price data from additional sources to assess heterogeneity of post-tax price changes. A continued examination of the impact of the SSB tax in Barbados will expand the evidence base available to policymakers worldwide in considering SSB taxes as a lever for reducing the consumption of added sugar at the population level. Copyright © 2017. Published by Elsevier Inc.

Chemo-mechanical pushing of proteins along single-stranded DNA

PubMed Central

Sokoloski, Joshua E.; Kozlov, Alexander G.; Galletto, Roberto; Lohman, Timothy M.

2016-01-01

Single-stranded (ss)DNA binding (SSB) proteins bind with high affinity to ssDNA generated during DNA replication, recombination, and repair; however, these SSBs must eventually be displaced from or reorganized along the ssDNA. One potential mechanism for reorganization is for an ssDNA translocase (ATP-dependent motor) to push the SSB along ssDNA. Here we use single molecule total internal reflection fluorescence microscopy to detect such pushing events. When Cy5-labeled Escherichia coli (Ec) SSB is bound to surface-immobilized 3′-Cy3–labeled ssDNA, a fluctuating FRET signal is observed, consistent with random diffusion of SSB along the ssDNA. Addition of Saccharomyces cerevisiae Pif1, a 5′ to 3′ ssDNA translocase, results in the appearance of isolated, irregularly spaced saw-tooth FRET spikes only in the presence of ATP. These FRET spikes result from translocase-induced directional (5′ to 3′) pushing of the SSB toward the 3′ ssDNA end, followed by displacement of the SSB from the DNA end. Similar ATP-dependent pushing events, but in the opposite (3′ to 5′) direction, are observed with EcRep and EcUvrD (both 3′ to 5′ ssDNA translocases). Simulations indicate that these events reflect active pushing by the translocase. The ability of translocases to chemo-mechanically push heterologous SSB proteins along ssDNA provides a potential mechanism for reorganization and clearance of tightly bound SSBs from ssDNA. PMID:27185951

Racial Disparities in Sugar-Sweetened Beverage Consumption Change Efficacy Among Male First-Year College Students

PubMed Central

Bruce, Marino A.; Beech, Bettina M.; Thorpe, Roland J.; Griffith, Derek M.

2016-01-01

Racial disparities in weight-related outcomes among males may be linked to differences in behavioral change efficacy; however, few studies have pursued this line of inquiry. The purpose of this study was to determine the degree to which self-efficacy associated with changing sugar-sweetened beverage (SSB) consumption intake varies by race among male first-year college students. A self-administered, cross-sectional survey was completed by a subsample of freshmen males (N = 203) at a medium-sized southern university. Key variables of interest were SSB intake and self-efficacy in reducing consumption of sugared beverages. African American and Whites had similar patterns of SSB intake (10.2 ± 2.8 vs. 10.1 ± 2.6); however, African Americans had lower proportions of individuals who were sure they could substitute sugared beverages with water (42.2% vs. 57.5%, p < .03). The results from logistic regression models suggest that self-efficacy to reduce SSB intake among males vary by race. African American males were less likely to assert confidence in their ability to change behaviors associated with SSB (odds ratio = 0.51; confidence interval [0.27, 0.95]) in the full model adjusting for weight-related variables including SSB consumption. The findings suggest that weight loss and weight prevention interventions targeting young African American males require components that can elevate self-efficacy of this group to facilitate behavioral modifications that reduce SSB consumption and their risk for obesity-related diseases. PMID:26272888

U.S. adults and child snacking patterns among sugar sweetened beverage drinkers and non-drinkers

PubMed Central

Bleich, Sara N.; Wolfson, Julia A.

2015-01-01

Objective To provide national estimates of snack patterns for sugar sweetened beverage (SSB) drinkers and non-SSB drinkers among U.S. children and adults. Methods We analyzed 24-hour dietary recall data obtained from the National Health and Nutrition Examination Survey 1999–2010 among children (ages 2 to 19) and adults (aged 20 and older) (N = 46,932). Results For children and adults, SSB drinkers were significantly more likely than non-SSB drinkers to consume snacks (children: salty – 60% vs. 50%; sweet – 69% vs. 65%; adults: salty – 64% vs. 58%; sweet – 64% vs. 58%), calories from snacks (children: salty snacks – 258 vs. 213 kcal; sweet snacks – 322 vs. 291 kcal; adults: salty snacks – 261 vs. 236 kcal; sweet snacks – 370 vs. 350 kcal), and total calories (children: 2098 vs. 1804 kcal; adults: 2329 vs. 2049 kcal) (p < 0.05). Among adolescents, Blacks had a significantly higher percentage of SSB drinkers and salty snack consumers than Whites and Hispanics (SSB consumers: White – 79%; Black – 86%, Hispanic – 82%; salty snack consumers: White – 56%; Black – 62%, Hispanic – 54%; p < 0.05). All ages were more likely to consume sweet snacks at home (p < 0.05). Conclusions Adults and children who drink SSBs are more likely to snack and consume more calories from snacks than non-SSB drinkers, particularly Black adolescents and young adults. PMID:25584987

Racial Disparities in Sugar-Sweetened Beverage Consumption Change Efficacy Among Male First-Year College Students.

PubMed

Bruce, Marino A; Beech, Bettina M; Thorpe, Roland J; Griffith, Derek M

2016-11-01

Racial disparities in weight-related outcomes among males may be linked to differences in behavioral change efficacy; however, few studies have pursued this line of inquiry. The purpose of this study was to determine the degree to which self-efficacy associated with changing sugar-sweetened beverage (SSB) consumption intake varies by race among male first-year college students. A self-administered, cross-sectional survey was completed by a subsample of freshmen males (N = 203) at a medium-sized southern university. Key variables of interest were SSB intake and self-efficacy in reducing consumption of sugared beverages. African American and Whites had similar patterns of SSB intake (10.2 ± 2.8 vs. 10.1 ± 2.6); however, African Americans had lower proportions of individuals who were sure they could substitute sugared beverages with water (42.2% vs. 57.5%, p < .03). The results from logistic regression models suggest that self-efficacy to reduce SSB intake among males vary by race. African American males were less likely to assert confidence in their ability to change behaviors associated with SSB (odds ratio = 0.51; confidence interval [0.27, 0.95]) in the full model adjusting for weight-related variables including SSB consumption. The findings suggest that weight loss and weight prevention interventions targeting young African American males require components that can elevate self-efficacy of this group to facilitate behavioral modifications that reduce SSB consumption and their risk for obesity-related diseases. © The Author(s) 2015.

Receiver concepts for data transmission at 10 microns

NASA Astrophysics Data System (ADS)

Scholtz, A. L.; Philipp, H. K.; Leeb, W. R.

1984-05-01

Receivers for digitally modulated CO2 laser signals are compared. Incoherent heterodyne receivers and coherent homodyne setups, including the linear phase locked loop (PLL) receiver, the low intermediate frequency translation loop, and the Costas loop receiver were studied. Experiments covered the homodyne systems, emphasizing the linear PLL receiver. Reliable phase lock of the receiver is achieved at carrier levels as low as 3 nW. Reception of signals phase shift keyed with a data rate of up to 150 Mbit/sec is demonstrated at subnanowatt sideband power levels.

Preparation of an exponentially rising optical pulse for efficient excitation of single atoms in free space.

PubMed

Dao, Hoang Lan; Aljunid, Syed Abdullah; Maslennikov, Gleb; Kurtsiefer, Christian

2012-08-01

We report on a simple method to prepare optical pulses with exponentially rising envelope on the time scale of a few ns. The scheme is based on the exponential transfer function of a fast transistor, which generates an exponentially rising envelope that is transferred first on a radio frequency carrier, and then on a coherent cw laser beam with an electro-optical phase modulator. The temporally shaped sideband is then extracted with an optical resonator and can be used to efficiently excite a single (87)Rb atom.

Ion trap simulations of quantum fields in an expanding universe.

PubMed

Alsing, Paul M; Dowling, Jonathan P; Milburn, G J

2005-06-10

We propose an experiment in which the phonon excitation of ion(s) in a trap, with a trap frequency exponentially modulated at rate kappa, exhibits a thermal spectrum with an "Unruh" temperature given by k(B)T=Planck kappa. We discuss the similarities of this experiment to the response of detectors in a de Sitter universe and the usual Unruh effect for uniformly accelerated detectors. We demonstrate a new Unruh effect for detectors that respond to antinormally ordered moments using the ion's first blue sideband transition.

Frequency agile microwave photonic notch filter with anomalously high stopband rejection.

PubMed

Marpaung, David; Morrison, Blair; Pant, Ravi; Eggleton, Benjamin J

2013-11-01

We report a novel class microwave photonic (MWP) notch filter with a very narrow isolation bandwidth (10 MHz), an ultrahigh stopband rejection (>60 dB), a wide frequency tuning (1-30 GHz), and flexible bandwidth reconfigurability (10-65 MHz). This performance is enabled by a new concept of sideband amplitude and phase controls using an electro-optic modulator and an optical filter. This concept enables energy efficient operation in active MWP notch filters, and opens up a pathway toward enabling low-power nanophotonic devices as high-performance RF filters.

Laser frequency stabilization and shifting by using modulation transfer spectroscopy

NASA Astrophysics Data System (ADS)

Cheng, Bing; Wang, Zhao-Ying; Wu, Bin; Xu, Ao-Peng; Wang, Qi-Yu; Xu, Yun-Fei; Lin, Qiang

2014-10-01

The stabilizing and shifting of laser frequency are very important for the interaction between the laser and atoms. The modulation transfer spectroscopy for the 87Rb atom with D2 line transition F = 2 → F' = 3 is used for stabilizing and shifting the frequency of the external cavity grating feedback diode laser. The resonant phase modulator with electro—optical effect is used to generate frequency sideband to lock the laser frequency. In the locking scheme, circularly polarized pump- and probe-beams are used. By optimizing the temperature of the vapor, the pump- and probe-beam intensity, the laser linewidth of 280 kHz is obtained. Furthermore, the magnetic field generated by a solenoid is added into the system. Therefore the system can achieve the frequency locking at any point in a range of hundreds of megahertz frequency shifting with very low power loss.

Nonlinear dynamics near the stability margin in rotating pipe flow

NASA Technical Reports Server (NTRS)

Yang, Z.; Leibovich, S.

1991-01-01

The nonlinear evolution of marginally unstable wave packets in rotating pipe flow is studied. These flows depend on two control parameters, which may be taken to be the axial Reynolds number R and a Rossby number, q. Marginal stability is realized on a curve in the (R, q)-plane, and the entire marginal stability boundary is explored. As the flow passes through any point on the marginal stability curve, it undergoes a supercritical Hopf bifurcation and the steady base flow is replaced by a traveling wave. The envelope of the wave system is governed by a complex Ginzburg-Landau equation. The Ginzburg-Landau equation admits Stokes waves, which correspond to standing modulations of the linear traveling wavetrain, as well as traveling wave modulations of the linear wavetrain. Bands of wavenumbers are identified in which the nonlinear modulated waves are subject to a sideband instability.

Tunable microwave generation based on frequency quadrupling

NASA Astrophysics Data System (ADS)

Liu, Yu-Lei; Liang, Jun; Li, Xuan; Xiao, Nan; Yuan, Xiao-Gang

2018-07-01

To generate linearly chirped microwave signals with large frequency tunable range, a photonic approach is proposed. A dual-output dual-parallel Mach-Zehnder modulator followed by a polarisation beam combiner and an optical filter are utilised to generate orthogonally polarised ± second-order optical sidebands. A polarisation modulator is employed to achieve phase modulation of the two wavelengths. The balanced detection is applied to suppress the distortion and background noise. The central frequency of the generated signal is four times that of the local oscillator frequency. Simulation results show that a linear pulse is produced with time-bandwidth as well as a compression ratio for the pulse of 11 and 9.3 respectively. Moreover, a peak-to-sidelobe ratio of 7.4 dB is generated. The system has both good reconfigurability and tunability, and its frequency can be continuously adjusted from about 10 GHz to as much as 50 GHz in principle.

PolSK Label Over VSB-CSRZ Payload Scheme in AOLS Network

NASA Astrophysics Data System (ADS)

Chen, Hongwei; Chen, Minghua; Xie, Shizhong

2007-06-01

A novel orthogonal modulation scheme of polarization-shift-keying label over vestigial sideband payload is proposed and experimentally demonstrated over a 43-Gb/s all-optical-label-switching transmission. With this scheme, a high extinction ratio of the label is reached, while a spectral efficiency of 0.8 b/s/Hz is achieved by weakening the imperfection of the high-speed pulse sequence in polarization modulation. Furthermore, this modulation scheme is relatively irrelevant with payload bit rate. The payload and label penalties after 80-km NZDSF fiber transmission and label erasure are 1.5 and 1 dB, respectively. The influence of filter center frequency offset is also investigated. Besides, a label rewriting method is introduced to simplify label processing in intermedia nodes. All these results show that this scheme can be a candidate technique for the next-generation optical network.

Polarization rotation vector solitons in a graphene mode-locked fiber laser.

PubMed

Song, Yu Feng; Zhang, Han; Tang, Ding Yuan; Shen, De Yuan

2012-11-19

Polarization rotation vector solitons formed in a fiber laser passively mode locked with atomic layer graphene were experimentally investigated. It was found that different from the case of the polarization locked vector soliton formed in the laser, two extra sets of spectral sidebands always appear on the soliton spectrum of the polarization rotating vector solitons. We confirm that the new sets of spectral sidebands have the same formation mechanism as that of the Kelly sidebands.

Effects of sound intensity on temporal properties of inhibition in the pallid bat auditory cortex.

PubMed

Razak, Khaleel A

2013-01-01

Auditory neurons in bats that use frequency modulated (FM) sweeps for echolocation are selective for the behaviorally-relevant rates and direction of frequency change. Such selectivity arises through spectrotemporal interactions between excitatory and inhibitory components of the receptive field. In the pallid bat auditory system, the relationship between FM sweep direction/rate selectivity and spectral and temporal properties of sideband inhibition have been characterized. Of note is the temporal asymmetry in sideband inhibition, with low-frequency inhibition (LFI) exhibiting faster arrival times compared to high-frequency inhibition (HFI). Using the two-tone inhibition over time (TTI) stimulus paradigm, this study investigated the interactions between two sound parameters in shaping sideband inhibition: intensity and time. Specifically, the impact of changing relative intensities of the excitatory and inhibitory tones on arrival time of inhibition was studied. Using this stimulation paradigm, single unit data from the auditory cortex of pentobarbital-anesthetized cortex show that the threshold for LFI is on average ~8 dB lower than HFI. For equal intensity tones near threshold, LFI is stronger than HFI. When the inhibitory tone intensity is increased further from threshold, the strength asymmetry decreased. The temporal asymmetry in LFI vs. HFI arrival time is strongest when the excitatory and inhibitory tones are of equal intensities or if excitatory tone is louder. As inhibitory tone intensity is increased, temporal asymmetry decreased suggesting that the relative magnitude of excitatory and inhibitory inputs shape arrival time of inhibition and FM sweep rate and direction selectivity. Given that most FM bats use downward sweeps as echolocation calls, a similar asymmetry in threshold and strength of LFI vs. HFI may be a general adaptation to enhance direction selectivity while maintaining sweep-rate selective responses to downward sweeps.

Brillouin Selective Sideband Amplification of Microwave Photonic Signals

NASA Technical Reports Server (NTRS)

Yao, S.

1997-01-01

We introduce a powerful Brillouin selective sideband amplification technique and demonstrate its application for achieving gain in photonix signal up- and down- conversions in microwave photonic systems.

Sideband instability analysis based on a one-dimensional high-gain free electron laser model

DOE PAGES

Tsai, Cheng-Ying; Wu, Juhao; Yang, Chuan; ...

2017-12-18

When an untapered high-gain free electron laser (FEL) reaches saturation, the exponential growth ceases and the radiation power starts to oscillate about an equilibrium. The FEL radiation power or efficiency can be increased by undulator tapering. For a high-gain tapered FEL, although the power is enhanced after the first saturation, it is known that there is a so-called second saturation where the FEL power growth stops even with a tapered undulator system. The sideband instability is one of the primary reasons leading to this second saturation. In this paper, we provide a quantitative analysis on how the gradient of undulatormore » tapering can mitigate the sideband growth. The study is carried out semianalytically and compared with one-dimensional numerical simulations. The physical parameters are taken from Linac Coherent Light Source-like electron bunch and undulator systems. The sideband field gain and the evolution of the radiation spectra for different gradients of undulator tapering are examined. It is found that a strong undulator tapering (~10 % ) provides effective suppression of the sideband instability in the postsaturation regime.« less

Sideband instability analysis based on a one-dimensional high-gain free electron laser model

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

Tsai, Cheng-Ying; Wu, Juhao; Yang, Chuan

When an untapered high-gain free electron laser (FEL) reaches saturation, the exponential growth ceases and the radiation power starts to oscillate about an equilibrium. The FEL radiation power or efficiency can be increased by undulator tapering. For a high-gain tapered FEL, although the power is enhanced after the first saturation, it is known that there is a so-called second saturation where the FEL power growth stops even with a tapered undulator system. The sideband instability is one of the primary reasons leading to this second saturation. In this paper, we provide a quantitative analysis on how the gradient of undulatormore » tapering can mitigate the sideband growth. The study is carried out semianalytically and compared with one-dimensional numerical simulations. The physical parameters are taken from Linac Coherent Light Source-like electron bunch and undulator systems. The sideband field gain and the evolution of the radiation spectra for different gradients of undulator tapering are examined. It is found that a strong undulator tapering (~10 % ) provides effective suppression of the sideband instability in the postsaturation regime.« less

Optical sideband spectroscopy of a single ion in a Penning trap

NASA Astrophysics Data System (ADS)

Mavadia, S.; Stutter, G.; Goodwin, J. F.; Crick, D. R.; Thompson, R. C.; Segal, D. M.

2014-03-01

We perform resolved optical sideband spectroscopy on a single 40Ca+ ion in a Penning trap. We probe the electric quadrupole allowed S1/2↔D5/2 transition at 729 nm and observe equally spaced sidebands for the three motional modes. The axial mode, parallel to the trap axis, is a one-dimensional harmonic oscillator, whereas the radial cyclotron and magnetron modes are circular motions perpendicular to the magnetic field. The total energy associated with the magnetron motion is negative, but here we probe only the (positive) kinetic energy. From the equivalent Doppler widths of the sideband spectra corresponding to the three motions we find effective temperatures of 1.1±0.2 mK, 7±3 mK, and 42±8 μK for the axial, modified cyclotron, and magnetron modes, respectively. These should be compared to the cooling limits, estimated using optimal laser parameters, of 0.38 mK, 0.8 mK, and ˜10 μK. In future work we aim to perform resolved-sideband cooling of the ion on the 729-nm transition.

Sideband instability analysis based on a one-dimensional high-gain free electron laser model

NASA Astrophysics Data System (ADS)

Tsai, Cheng-Ying; Wu, Juhao; Yang, Chuan; Yoon, Moohyun; Zhou, Guanqun

2017-12-01

When an untapered high-gain free electron laser (FEL) reaches saturation, the exponential growth ceases and the radiation power starts to oscillate about an equilibrium. The FEL radiation power or efficiency can be increased by undulator tapering. For a high-gain tapered FEL, although the power is enhanced after the first saturation, it is known that there is a so-called second saturation where the FEL power growth stops even with a tapered undulator system. The sideband instability is one of the primary reasons leading to this second saturation. In this paper, we provide a quantitative analysis on how the gradient of undulator tapering can mitigate the sideband growth. The study is carried out semianalytically and compared with one-dimensional numerical simulations. The physical parameters are taken from Linac Coherent Light Source-like electron bunch and undulator systems. The sideband field gain and the evolution of the radiation spectra for different gradients of undulator tapering are examined. It is found that a strong undulator tapering (˜10 %) provides effective suppression of the sideband instability in the postsaturation regime.

Impact of resistive MHD plasma response on perturbation field sidebands

DOE PAGES

Orlov, D. M.; Evans, T. E.; Moyer, R. A.; ...

2016-06-03

Here, single fluid linear simulations of a KSTAR RMP ELM suppressed discharge with the M3D-C 1 resistive magnetohydrodynamic code have been performed for the first time. The simulations show that the application of the n = 1 perturbation using the KSTAR in-vessel control coils (IVCC), which apply modest levels of n = 3 sidebands (~20% of the n = 1), leads to levels of n = 3 sideband that are comparable to the n = 1 when plasma response is included. This is due to the reduced level of screening of the rational-surface-resonant n = 3 component relative to themore » rational-surface-resonant n = 1 component. The n = 3 sidebands could play a similar role in ELM suppression on KSTAR as the toroidal sidebands (n = 1, 2, 4) in DIII-D n = 3 ELM suppression with missing I-coil segments. This result may help to explain the uniqueness of ELM suppression with n = 1 perturbations in KSTAR since the effective perturbation is a mixed n = 1/n = 3 perturbation similar to n = 3 ELM suppression in DIII-D.« less

[Demographic and socioeconomic differences in consumption of sugar-sweetened beverages among Colombian children and adolescents].

PubMed

Ramírez-Vélez, Robinson; González-Ruíz, Katherine; Correa-Bautista, Jorge Enrique; Meneses-Echávez, José Francisco; Martínez-Torres, Javier

2015-06-01

Sugar-sweetened beverages (SSB) are becoming a common component in the diets among children and adolescents, and its consumption is associated with an increased risk factors for cardiovascular disease. The aim of the present study was to describe the consumption of sugar-sweetened beverages among Colombian children and adolescents and to examine whether differences by demographic and socioeconomic according to gender. We used data from the 2010 National Nutrition Survey of Colombia (ENSIN 2010) for 10,373 children and adolescents between 5 and 17 years old. SSB intake was based on intake from regular soda and/ or concentrated drinks. Demographic factors (sex, age, ethnicity, urbanicity, area and geographic region) and socioeconomic level (social class) were collected by structured questionnaire. Associations were established through a multivariate logistic regression. All analyzes were calculated by complex samples. Nationwide, 23% of girls and 22.4% of boys drank SSB at least once a week. Differences by demographic factors were observed for SSB consumption. In girls, factors associated with a greater odds for SSB intake (≥ 1 time/week) were aged 14 to 17 years old [OR = 1.65 (95%CI = 1.32, 2.06)], living in the central region [OR = 2.42 (95%CI = 1.81, 3.25)] and urban area [OR = 1.77 (95%CI = 1.42, 2.20)]. In boys, the multivariate logistic regression shows that adolescents aged 14 to 17 years old [OR = 1.96 (95%CI = 1.58, 2.24)], living in the national territories (South) [OR = 2.42 (95%CI = 1.77, 3.32)] and urban area [OR = 1.79 (95%CI = 1.45, 2.20)] were associated with a higher probability of SSB consumption. Social class was not associated with SSB intake. SSB intake varies by certain demographic factors. Government can use findings from this study to tailor efforts to decrease SSB intake and to encourage consumption of more healthful beverages (e.g, water) among Colombian children and adolescents. Copyright AULA MEDICA EDICIONES 2014. Published by AULA MEDICA. All rights reserved.

Controlled cohort evaluation of the LiveLighter mass media campaign's impact on adults' reported consumption of sugar-sweetened beverages.

PubMed

Morley, Belinda C; Niven, Philippa H; Dixon, Helen G; Swanson, Maurice G; McAleese, Alison B; Wakefield, Melanie A

2018-04-25

To evaluate the LiveLighter 'Sugary Drinks' campaign impact on awareness, knowledge and sugar-sweetened beverage (SSB) consumption. Cohort study with population surveys undertaken in intervention and comparison states at baseline (n=900 each), with 78% retention at follow-up (intervention: n=673; comparison: n=730). Analyses tested interactions by state (intervention, comparison) and time (baseline, follow-up). Adults aged 25-49 years residing in the Australian states of Victoria and South Australia. The 6-week mass media campaign ran in Victoria in October/November 2015. It focused on the contribution of SSBs to the development of visceral 'toxic fat', graphically depicted around vital organs, and ultimately serious disease. Paid television advertising was complemented by radio, cinema, online and social media advertising, and stakeholder and community engagement. Self-reported consumption of SSBs, artificially sweetened drinks and water. Campaign recall and recognition; knowledge of the health effects of overweight and SSB consumption; perceived impact of SSB consumption on body weight and of reduced consumption on health. A significant reduction in frequent SSB consumption was observed in the intervention state (intervention: 31% compared with 22%, comparison: 30% compared with 29%; interaction p<0.01). This was accompanied by evidence of increased water consumption (intervention: 66% compared with 73%; comparison: 68% compared with 67%; interaction p=0.09) among overweight/obese SSB consumers. This group also showed increased knowledge of the health effects of SSB consumption (intervention: 60% compared with 71%, comparison: 63% compared with 59%; interaction p<0.05) and some evidence of increased prevalence of self-referent thoughts about SSB's relationship to weight gain (intervention: 39% compared with 45%, comparison: 43% compared with 38%; interaction p=0.06). The findings provide evidence of reduced SSB consumption among adults in the target age range following the LiveLighter campaign. This is notable in a context where public health campaigns occur against a backdrop of heavy commercial product advertising promoting increased SSB consumption. © Article author(s) (or their employer(s) unless otherwise stated in the text of the article) 2018. All rights reserved. No commercial use is permitted unless otherwise expressly granted.

Averting obesity and type 2 diabetes in India through sugar-sweetened beverage taxation: an economic-epidemiologic modeling study.

PubMed

Basu, Sanjay; Vellakkal, Sukumar; Agrawal, Sutapa; Stuckler, David; Popkin, Barry; Ebrahim, Shah

2014-01-01

Taxing sugar-sweetened beverages (SSBs) has been proposed in high-income countries to reduce obesity and type 2 diabetes. We sought to estimate the potential health effects of such a fiscal strategy in the middle-income country of India, where there is heterogeneity in SSB consumption, patterns of substitution between SSBs and other beverages after tax increases, and vast differences in chronic disease risk within the population. Using consumption and price variations data from a nationally representative survey of 100,855 Indian households, we first calculated how changes in SSB price alter per capita consumption of SSBs and substitution with other beverages. We then incorporated SSB sales trends, body mass index (BMI), and diabetes incidence data stratified by age, sex, income, and urban/rural residence into a validated microsimulation of caloric consumption, glycemic load, overweight/obesity prevalence, and type 2 diabetes incidence among Indian subpopulations facing a 20% SSB excise tax. The 20% SSB tax was anticipated to reduce overweight and obesity prevalence by 3.0% (95% CI 1.6%-5.9%) and type 2 diabetes incidence by 1.6% (95% CI 1.2%-1.9%) among various Indian subpopulations over the period 2014-2023, if SSB consumption continued to increase linearly in accordance with secular trends. However, acceleration in SSB consumption trends consistent with industry marketing models would be expected to increase the impact efficacy of taxation, averting 4.2% of prevalent overweight/obesity (95% CI 2.5-10.0%) and 2.5% (95% CI 1.0-2.8%) of incident type 2 diabetes from 2014-2023. Given current consumption and BMI distributions, our results suggest the largest relative effect would be expected among young rural men, refuting our a priori hypothesis that urban populations would be isolated beneficiaries of SSB taxation. Key limitations of this estimation approach include the assumption that consumer expenditure behavior from prior years, captured in price elasticities, will reflect future behavior among consumers, and potential underreporting of consumption in dietary recall data used to inform our calculations. Sustained SSB taxation at a high tax rate could mitigate rising obesity and type 2 diabetes in India among both urban and rural subpopulations.

Cascade photonic integrated circuit architecture for electro-optic in-phase quadrature/single sideband modulation or frequency conversion.

PubMed

Hasan, Mehedi; Hall, Trevor

2015-11-01

A photonic integrated circuit architecture for implementing frequency upconversion is proposed. The circuit consists of a 1×2 splitter and 2×1 combiner interconnected by two stages of differentially driven phase modulators having 2×2 multimode interference coupler between the stages. A transfer matrix approach is used to model the operation of the architecture. The predictions of the model are validated by simulations performed using an industry standard software tool. The intrinsic conversion efficiency of the proposed design is improved by 6 dB over the alternative functionally equivalent circuit based on dual parallel Mach-Zehnder modulators known in the prior art. A two-tone analysis is presented to study the linearity of the proposed circuit, and a comparison is provided over the alternative. The proposed circuit is suitable for integration in any platform that offers linear electro-optic phase modulation such as LiNbO(3), silicon, III-V, or hybrid technology.

Enhanced accuracy of the microwave field strength measurement in a CW-EPR by pulsed modulation technique

NASA Astrophysics Data System (ADS)

Rakvin, B.; Carić, D.; Kveder, M.

2018-02-01

The microwave magnetic field strength, B1, in the cavity of a conventional continuous wave electron paramagnetic resonance, CW-EPR, spectrometer was measured by employing modulation sidebands, MS, in the EPR spectrum. MS spectrum in CW-EPR is produced by applying the modulation frequency, ωrf, which exceeds the linewidth, δB, given in frequency units. An amplitude-modulated CW-EPR, AM-CW-EPR, was selected as detection method. Theoretical description of AM-CW-EPR spectrum was modified by adding Bloch-Siegert-like shift obtained by taking into account the cumulative effect of the non-resonant interactions between the driving fields and the spin system. This approach enables to enhance the precision of B1 measurement. In order to increase the sensitivity of the method when saturation effects, due to higher intensity of B1, decrease the resolution of AM-CW-EPR spectrum, detection at the second harmonic of CW-EPR has been employed.

Enhanced accuracy of the microwave field strength measurement in a CW-EPR by pulsed modulation technique.

PubMed

Rakvin, B; Carić, D; Kveder, M

2018-02-01

The microwave magnetic field strength, B 1 , in the cavity of a conventional continuous wave electron paramagnetic resonance, CW-EPR, spectrometer was measured by employing modulation sidebands, MS, in the EPR spectrum. MS spectrum in CW-EPR is produced by applying the modulation frequency, ω rf , which exceeds the linewidth, δB, given in frequency units. An amplitude-modulated CW-EPR, AM-CW-EPR, was selected as detection method. Theoretical description of AM-CW-EPR spectrum was modified by adding Bloch-Siegert-like shift obtained by taking into account the cumulative effect of the non-resonant interactions between the driving fields and the spin system. This approach enables to enhance the precision of B 1 measurement. In order to increase the sensitivity of the method when saturation effects, due to higher intensity of B 1 , decrease the resolution of AM-CW-EPR spectrum, detection at the second harmonic of CW-EPR has been employed. Copyright © 2018 Elsevier Inc. All rights reserved.

Study of magnetic resonance with parametric modulation in a potassium vapor cell

NASA Astrophysics Data System (ADS)

Zhang, Rui; Wang, Zhiguo; Peng, Xiang; Li, Wenhao; Li, Songjian; Guo, Hong; Cream Team

2017-04-01

A typical magnetic-resonance scheme employs a static bias magnetic field and an orthogonal driving magnetic field oscillating at the Larmor frequency, at which the atomic polarization precesses around the static magnetic field. We demonstrate in a potassium vapor cell the variations of the resonance condition and the spin precession dynamics resulting from the parametric modulation of the bias field, which are in well agreement with theoretical predictions from the Bloch equation. We show that, the driving magnetic field with the frequency detuned by different harmonics of the parametric modulation frequency can lead to resonance as well. Also, a series of frequency sidebands centered at the driving frequency and spaced by the parametric modulation frequency can be observed in the precession of the atomic polarization. These effects could be used in different atomic magnetometry applications. This work is supported by the National Science Fund for Distinguished Young Scholars of China (Grant No. 61225003) and the National Natural Science Foundation of China (Grant Nos. 61531003 and 61571018).

Coherent detection of THz-induced sideband emission from excitons in the nonperturbative regime

NASA Astrophysics Data System (ADS)

Uchida, K.; Otobe, T.; Mochizuki, T.; Kim, C.; Yoshita, M.; Tanaka, K.; Akiyama, H.; Pfeiffer, L. N.; West, K. W.; Hirori, H.

2018-04-01

Strong interaction of a terahertz (THz) wave with excitons induces nonperturbative optical effects such as Rabi splitting and high-order sideband generation. Here, we investigated coherent properties of THz-induced sideband emissions from GaAs/AlGaAs multiquantum wells. With increasing THz electric field, optical susceptibility of the THz-dressed exciton shows a redshift with spectral broadening and extraordinary phase shift. This implies that the field ionization of the 1 s exciton modifies the THz-dressed exciton in the nonperturbative regime.

The Free Electron Laser Sideband Instability Reconsidered.

DTIC Science & Technology

1987-08-12

sidebands. The stability is determined by the sign of df /dtl i.e., the relative population of oscillation quanta Wwb, bounce frequency around resonance. The...wigglers. (e) The growth is proportional to [df(J)/d(b(J)], the relative population in oscillation quanta around resonance, in agreement with the quantum...signal and the sideband. The total vector potential is given by A eie )A weik ) z( eiey )Arei(krZ- t) (exiey)A sei(ksz-& st) + CC (2) where the subscripts w

Symmetry breaking, Josephson oscillation and self-trapping in a self-bound three-dimensional quantum ball.

PubMed

Adhikari, S K

2017-11-22

We study spontaneous symmetry breaking (SSB), Josephson oscillation, and self-trapping in a stable, mobile, three-dimensional matter-wave spherical quantum ball self-bound by attractive two-body and repulsive three-body interactions. The SSB is realized by a parity-symmetric (a) one-dimensional (1D) double-well potential or (b) a 1D Gaussian potential, both along the z axis and no potential along the x and y axes. In the presence of each of these potentials, the symmetric ground state dynamically evolves into a doubly-degenerate SSB ground state. If the SSB ground state in the double well, predominantly located in the first well (z > 0), is given a small displacement, the quantum ball oscillates with a self-trapping in the first well. For a medium displacement one encounters an asymmetric Josephson oscillation. The asymmetric oscillation is a consequence of SSB. The study is performed by a variational and a numerical solution of a non-linear mean-field model with 1D parity-symmetric perturbations.

Worksite nutrition supports and sugar-sweetened beverage consumption.

PubMed

Hipp, J A; Becker, H V; Marx, C M; Tabak, R G; Brownson, R C; Yang, L

2016-06-01

This study examined the link between worksite environmental supports for nutrition behaviours and sugar-sweetened beverage (SSB) consumption and offers insight into potential intervention points for reducing SSB consumption and combatting overweight and obesity. Perceived worksite supports for healthy nutrition and self-reported SSB consumption were analysed for 2,015 working adults in the state of Missouri using a subset of questions from the Supports at Home and Work for Maintaining Energy Balance (SHOW-ME) study. Employees' use of vending facilities and the availability of water coolers/water bottles was significantly associated with increased SSB consumption, while use of cafeterias was significantly associated with decreased SSB consumption. Symbols or signs to identify healthy alternatives were significantly associated with sports drink consumption. This study supports previous work indicating the worksite as a necessary environment for nutrition interventions. When choices (vending and cafeteria) are provided, employees report making healthier decisions. For worksites without cafeterias, alternatives should be explored including mobile food trucks and farmer's markets.

Worksite nutrition supports and sugar‐sweetened beverage consumption

PubMed Central

Becker, H. V.; Marx, C. M.; Tabak, R. G.; Brownson, R. C.; Yang, L.

2016-01-01

Summary Objective This study examined the link between worksite environmental supports for nutrition behaviours and sugar‐sweetened beverage (SSB) consumption and offers insight into potential intervention points for reducing SSB consumption and combatting overweight and obesity. Methods Perceived worksite supports for healthy nutrition and self‐reported SSB consumption were analysed for 2,015 working adults in the state of Missouri using a subset of questions from the Supports at Home and Work for Maintaining Energy Balance (SHOW‐ME) study. Results Employees' use of vending facilities and the availability of water coolers/water bottles was significantly associated with increased SSB consumption, while use of cafeterias was significantly associated with decreased SSB consumption. Symbols or signs to identify healthy alternatives were significantly associated with sports drink consumption. Conclusions This study supports previous work indicating the worksite as a necessary environment for nutrition interventions. When choices (vending and cafeteria) are provided, employees report making healthier decisions. For worksites without cafeterias, alternatives should be explored including mobile food trucks and farmer's markets. PMID:29071097

Geospatial clustering in sugar-sweetened beverage consumption among Boston youth.

PubMed

Tamura, Kosuke; Duncan, Dustin T; Athens, Jessica K; Bragg, Marie A; Rienti, Michael; Aldstadt, Jared; Scott, Marc A; Elbel, Brian

2017-09-01

The objective was to detect geospatial clustering of sugar-sweetened beverage (SSB) intake in Boston adolescents (age = 16.3 ± 1.3 years [range: 13-19]; female = 56.1%; White = 10.4%, Black = 42.6%, Hispanics = 32.4%, and others = 14.6%) using spatial scan statistics. We used data on self-reported SSB intake from the 2008 Boston Youth Survey Geospatial Dataset (n = 1292). Two binary variables were created: consumption of SSB (never versus any) on (1) soda and (2) other sugary drinks (e.g., lemonade). A Bernoulli spatial scan statistic was used to identify geospatial clusters of soda and other sugary drinks in unadjusted models and models adjusted for age, gender, and race/ethnicity. There was no statistically significant clustering of soda consumption in the unadjusted model. In contrast, a cluster of non-soda SSB consumption emerged in the middle of Boston (relative risk = 1.20, p = .005), indicating that adolescents within the cluster had a 20% higher probability of reporting non-soda SSB intake than outside the cluster. The cluster was no longer significant in the adjusted model, suggesting spatial variation in non-soda SSB drink intake correlates with the geographic distribution of students by race/ethnicity, age, and gender.

Caloric compensation for sugar-sweetened beverages in meals: A population-based study in Brazil.

PubMed

Gombi-Vaca, Maria Fernanda; Sichieri, Rosely; Verly, Eliseu

2016-03-01

Sugar-sweetened beverage (SSB) consumption can cause positive energy balance, therefore leading to weight gain. A plausible biological mechanism to explain this association is through weak caloric compensation for liquid calories. However, there is an ongoing debate surrounding SSB calorie compensation. The body of evidence comes from a diversity of study designs and highly controlled settings assessing food and beverage intake. Our study aimed to test for caloric compensation of SSB in the free-living setting of daily meals. We analyzed two food records of participants (age 10 years or older) from the 2008-2009 National Dietary Survey (Brazil, N = 34,003). We used multilevel analyses to estimate the within-subject effects of SSB on food intake. Sugar-sweetened beverage calories were not compensated for when comparing daily energy intake over two days for each individual. When comparing meals, we found 42% of caloric compensation for breakfast, no caloric compensation for lunch and zero to 22% of caloric compensation for dinner, differing by household per capita income. In conclusion, SSB consumption contributed to higher energy intake due to weak caloric compensation. Discouraging the intake of SSB especially during lunch and dinner may help reduce excessive energy intake and lead to better weight management. Copyright © 2015 Elsevier Ltd. All rights reserved.

Saccharomyces cerevisiae SSB1 protein and its relationship to nucleolar RNA-binding proteins.

PubMed

Jong, A Y; Clark, M W; Gilbert, M; Oehm, A; Campbell, J L

1987-08-01

To better define the function of Saccharomyces cerevisiae SSB1, an abundant single-stranded nucleic acid-binding protein, we determined the nucleotide sequence of the SSB1 gene and compared it with those of other proteins of known function. The amino acid sequence contains 293 amino acid residues and has an Mr of 32,853. There are several stretches of sequence characteristic of other eucaryotic single-stranded nucleic acid-binding proteins. At the amino terminus, residues 39 to 54 are highly homologous to a peptide in calf thymus UP1 and UP2 and a human heterogeneous nuclear ribonucleoprotein. Residues 125 to 162 constitute a fivefold tandem repeat of the sequence RGGFRG, the composition of which suggests a nucleic acid-binding site. Near the C terminus, residues 233 to 245 are homologous to several RNA-binding proteins. Of 18 C-terminal residues, 10 are acidic, a characteristic of the procaryotic single-stranded DNA-binding proteins and eucaryotic DNA- and RNA-binding proteins. In addition, examination of the subcellular distribution of SSB1 by immunofluorescence microscopy indicated that SSB1 is a nuclear protein, predominantly located in the nucleolus. Sequence homologies and the nucleolar localization make it likely that SSB1 functions in RNA metabolism in vivo, although an additional role in DNA metabolism cannot be excluded.

A metabolomics approach to the identification of biomarkers of sugar-sweetened beverage intake.

PubMed

Gibbons, Helena; McNulty, Breige A; Nugent, Anne P; Walton, Janette; Flynn, Albert; Gibney, Michael J; Brennan, Lorraine

2015-03-01

The association between sugar-sweetened beverages (SSBs) and health risks remains controversial. To clarify proposed links, reliable and accurate dietary assessment methods of food intakes are essential. The aim of this present work was to use a metabolomics approach to identify a panel of urinary biomarkers indicative of SSB consumption from a national food consumption survey and subsequently validate this panel in an acute intervention study. Heat map analysis was performed to identify correlations between ¹H nuclear magnetic resonance (NMR) spectral regions and SSB intakes in participants of the National Adult Nutrition Survey (n = 565). Metabolites were identified and receiver operating characteristic (ROC) analysis was performed to assess sensitivity and specificity of biomarkers. The panel of biomarkers was validated in an acute study (n = 10). A fasting first-void urine sample and postprandial samples (2, 4, 6 h) were collected after SSB consumption. After NMR spectroscopic profiling of the urine samples, multivariate data analysis was applied. A panel of 4 biomarkers-formate, citrulline, taurine, and isocitrate-were identified as markers of SSB intake. This panel of biomarkers had an area under the curve of 0.8 for ROC analysis and a sensitivity and specificity of 0.7 and 0.8, respectively. All 4 biomarkers were identified in the SSB sample. After acute consumption of an SSB drink, all 4 metabolites increased in the urine. The present metabolomics-based strategy proved to be successful in the identification of SSB biomarkers. Future work will ascertain how to translate this panel of markers for use in nutrition epidemiology. © 2015 American Society for Nutrition.

Improvement of selective lignin degradation in fungal pretreatment of sweet sorghum bagasse using synergistic CuSO4-syringic acid supplements.

PubMed

Mishra, Vartika; Jana, Asim K; Jana, Mithu Maiti; Gupta, Antriksh

2017-05-15

Sweet sorghum bagasse (SSB) generated in large quantities could be hydrolyzed to sugar and then fermented to green fuels. The hydrolysis of SSB polysaccharides interlocked in recalcitrant lignin network is the major problem. Pretreatment of SSB in SSF by using Coriolus versicolor with CuSO 4 -syringic acid supplements for effects on production of ligninocellulolytic enzymes, lignin degradation and selectivity values (SV) were studied. C. versicolor was selected based on high ligninolytic and low cellulolytic abilily. Individually, CuSO 4 increased the activities of laccase (4.9 folds) and PPO (1.9 folds); syringic acid increased LiP (13 folds), AAO (2.8 folds) and laccase (5.6 folds) resulting in increased lignin degradation and SVs. Combined syringic acid (4.4 μmol g -1 SSB) and CuSO 4 (4.4 μmol g -1 SSB) increased the activities of laccase, LiP, MnP, PPO and AAO by 11.2, 17.6, 2.8, 2.4 and 2.3 folds respectively due to synergistic effect, resulting in maximum lignin degradation 35.9 ± 1.3% (w w -1 ) (1.86 fold) and highest SV 3.07 (4.7 fold). Enzymatic hydrolysis of pretreated SSB yielded higher (∼2.2 times) fermentable sugar. Pretreated SSB was characterized by XRD, SEM, FTIR and TGA/DTG analysis to confirm results. It is possible to improve fungal pretreatment of agricultural waste by combination of supplements. Copyright © 2017 Elsevier Ltd. All rights reserved.

Sugar-sweetened beverage intake and the risk of type I and type II endometrial cancer among postmenopausal women.

PubMed

Inoue-Choi, Maki; Robien, Kim; Mariani, Andrea; Cerhan, James R; Anderson, Kristin E

2013-12-01

Sugar-sweetened beverage (SSB) intake has been associated with an increased risk of obesity and type II diabetes. However, its association with endometrial cancer is unclear. We evaluated dietary intake of SSB, fruit juice, sugar-free beverages, sweets/baked goods, starch, and sugars among 23,039 postmenopausal women in the Iowa Women's Health Study. Incident estrogen-dependent type I and estrogen-independent type II endometrial cancers were identified via linkage with the Surveillance Epidemiology and End Results Registry. Risks of type I and type II endometrial cancers were separately compared by energy-adjusted dietary intake in Cox proportional hazards regression models. From 1986 to 2010, 506 type I and 89 type II incident endometrial cancers were identified. An increased risk of type I endometrial cancer was observed with increasing SSB intake after adjustment for body mass index (BMI) and other cofounders (Ptrend = 0.0005). Compared with nondrinkers of SSB, the risk was 78% higher [95% confidence intervals (CI), 1.32-2.40] among women in the highest quintile of SSB intake. The observed association was not modified by BMI, physical activity, history of diabetes, or cigarette smoking. Higher risk of type I endometrial cancer was also observed with higher intake of sugars. None of the dietary items included in the analysis was associated with type II endometrial cancer risk. Higher intake of SSB and sugars was associated with an increased risk of type I, but not type II, endometrial cancer. SSB intake may be a risk factor for type I endometrial cancer regardless of other lifestyle factors. ©2013 AACR.

Purification of ribonucleoproteins by a novel approach: isolation of the SSB1 ribonucleoprotein from yeast and demonstration that it has no role in mRNA splicing.

PubMed

Cusick, M E

1992-12-29

A novel approach is described to purify potential ribonucleoproteins (RNP) of yeast. The method assays a yeast RNP complex, assembled in vitro on actin pre-mRNA, by low-ionic strength acrylamide gel electrophoresis. The minimal protein components of this RNP complex were three proteins, one of 30 kDa and two at 42-44 kDa, defined by formation of the complex on biotinylated-RNA, binding of this complex to avidin-agarose, and salt elution of the protein in the biotinylated-RNP complex. Using the assay for RNP complex formation, an RNP protein was purified to homogeneity on the basis of its affinity towards single-stranded DNA and RNA. This RNP protein turned out to be identical to a known RNP protein, the single-stranded binding protein 1 (ssb1) of yeast, on the basis of identical gel electrophoretic migration, antibody cross-reactivity, and identical properties on the gel complex formation assay. In vitro mRNA splicing was normal in extracts made from a yeast strain missing ssb1 (ssb1- strain). Addition of anti-ssb1 antibody to splicing extracts made from a wild type strain did not inhibit or diminish splicing. Instead, mRNA splicing was reproducibly stimulated several fold, indicating competition between ssb1 and splicing factors for binding to single-stranded RNA in the extracts. RNP complexes still formed in the ssb1- strain, demonstrating that it would be possible to purify other RNP proteins from this strain using the gel complex formation assay.

Factors affecting sugar-sweetened beverage availability in competitive venues of US secondary schools.

PubMed

Terry-McElrath, Yvonne M; O'Malley, Patrick M; Johnston, Lloyd D

2012-01-01

This study explores sugar-sweetened beverage (SSB) availability in US secondary school competitive venues during the first 3 years following the school wellness policy requirement (2007-2009). Furthermore, analyses examine associations with school policy and SSB availability. Analyses use questionnaire data from 757 middle and 762 high schools in the nationally representative Youth, Education, and Society study to examine soda and non-soda SSB availability associations with school policy including (1) beverage bottling contracts and related incentives, (2) individuals/organizations responsible for decisions regarding beverages available in vending machines, and (3) school wellness policies and nutrition guidelines. Non-soda SSBs made up the majority of SSBs in both middle and high schools. Soda was especially likely to be found in vending machines; non-soda SSBs were widely available across competitive venues. Access to soda decreased significantly over time; however, non-soda SSB access did not show a similar decrease. School policy allowing beverage supplier contractual involvement (bottling contract incentives and beverage supplier "say" in vending machine beverage choices) was related to increased SSB access. However, the existence of developed nutritional guidelines was associated with lower SSB availability. Students had high access to SSBs across competitive school venues, with non-soda SSBs making up the majority of SSB beverage options. Efforts to reduce access to SSBs in US secondary schools should include a focus on reducing both soda and non-soda SSBs, reducing beverage supplier involvement in school beverage choices, and encouraging the development of targeted nutritional guidelines for all competitive venues. © 2011, American School Health Association.

Association Between Sugar-Sweetened Beverage Intake and Proxies of Acculturation Among U.S. Hispanic and Non-Hispanic White Adults

PubMed Central

Park, Sohyun; Blanck, Heidi M.; Dooyema, Carrie A.; Ayala, Guadalupe X.

2015-01-01

Purpose This study examined associations between sugar-sweetened beverage (SSB) intake and acculturation among a sample representing civilian noninstitutionalized U.S. adults. Design Quantitative, cross-sectional study. Setting National. Subjects The 2010 National Health Interview Survey data for 17,142 Hispanics and U.S.-born non-Hispanic whites (≥18 years). Measures The outcome variable was daily SSB intake (nondiet soda, fruit drinks, sports drinks, energy drinks, and sweetened coffee/tea drinks). Exposure variables were Hispanic ethnicity and proxies of acculturation (language of interview, birthplace, and years living in the United States). Analysis We used multivariate logistic regression to estimate adjusted odds ratios (ORs) for the exposure variables associated with drinking SSB ≥ 1 time/d after controlling for covariates. Results The adjusted odds of drinking SSB ≥ 1 time/d was significantly higher among Hispanics who completed the interview in Spanish (OR = 1.65) than U.S.-born non-Hispanic whites. Compared with those who lived in the United States for <5 years, the adjusted odds of drinking SSB ≥ 1 time/d was higher among adults who lived in the United States for 5 to <10 years (OR = 2.72), those who lived in the United States for 10 to <15 years (OR = 2.90), and those who lived in the United States for ≥15 years (OR = 2.41). However, birthplace was not associated with daily SSB intake. Conclusion The acculturation process is complex and these findings contribute to identifying important subpopulations that may benefit from targeted intervention to reduce SSB intake. PMID:27404644

Phylogenetic and Complementation Analysis of a Single-Stranded DNA Binding Protein Family from Lactococcal Phages Indicates a Non-Bacterial Origin

PubMed Central

Mariadassou, Mahendra; Bardowski, Jacek K.; Bidnenko, Elena

2011-01-01

Background The single-stranded-nucleic acid binding (SSB) protein superfamily includes proteins encoded by different organisms from Bacteria and their phages to Eukaryotes. SSB proteins share common structural characteristics and have been suggested to descend from an ancestor polypeptide. However, as other proteins involved in DNA replication, bacterial SSB proteins are clearly different from those found in Archaea and Eukaryotes. It was proposed that the corresponding genes in the phage genomes were transferred from the bacterial hosts. Recently new SSB proteins encoded by the virulent lactococcal bacteriophages (Orf14bIL67-like proteins) have been identified and characterized structurally and biochemically. Methodology/Principal Findings This study focused on the determination of phylogenetic relationships between Orf14bIL67-like proteins and other SSBs. We have performed a large scale phylogenetic analysis and pairwise sequence comparisons of SSB proteins from different phyla. The results show that, in remarkable contrast to other phage SSBs, the Orf14bIL67–like proteins form a distinct, self-contained and well supported phylogenetic group connected to the archaeal SSBs. Functional studies demonstrated that, despite the structural and amino acid sequence differences from bacterial SSBs, Orf14bIL67 protein complements the conditional lethal ssb-1 mutation of Escherichia coli. Conclusions/Significance Here we identified for the first time a group of phages encoded SSBs which are clearly distinct from their bacterial counterparts. All methods supported the recognition of these phage proteins as a new family within the SSB superfamily. Our findings suggest that unlike other phages, the virulent lactococcal phages carry ssb genes that were not acquired from their hosts, but transferred from an archaeal genome. This represents a unique example of a horizontal gene transfer between Archaea and bacterial phages. PMID:22073223

Perception v. actual intakes of junk food and sugar-sweetened beverages in Australian young adults: assessed using the mobile food record.

PubMed

Harray, Amelia J; Boushey, Carol J; Pollard, Christina M; Panizza, Chloe E; Delp, Edward J; Dhaliwal, Satvinder S; Kerr, Deborah A

2017-09-01

To determine perception v. actual intakes of energy-dense nutrient-poor 'junk food' (JF) and sugar-sweetened beverages (SSB) in young adults, using the mobile food record (mFR). Before-and-after eating images using a 4 d mFR were assessed for standardised 600 kJ (143 kcal) servings of JF and SSB (excluding diet drinks). Participants reported their concern about the health aspects of their diet, perceptions and intentions regarding JF and SSB. Perth, Western Australia. Adults (n 246) aged 18-30 years. The mean (sd) intake of JF+SSB was 3·7 (2·0) servings/d. Women thinking about drinking less SSB consumed more SSB servings/d (1·5 (1·2)) than men (0·7 (0·5); P<0·05) who were thinking about drinking less. Men not thinking about cutting down JF consumed more servings/d (4·6 (2·4)) than women (2·5 (0·7); P<0·01) who were not thinking about cutting down. Those who paid a lot of attention to the health aspects of their diet consumed less JF+SSB than those who took only a bit of notice (P<0·001), were not really thinking much about it (P<0·001) or who didn't think at all about the health aspects of food (P<0·01). Perceptions and attitudes regarding JF and SSB were associated with level of consumption. Those not thinking about cutting down their intake of these foods represent an important target group as they consume more than their peers. Further research is needed to identify how amenable young adults are to changing their intake, particularly given the lack of attention paid to the health aspects of their diet.

Estimated Global, Regional, and National Disease Burdens Related to Sugar-Sweetened Beverage Consumption in 2010

PubMed Central

Singh, Gitanjali M.; Micha, Renata; Khatibzadeh, Shahab; Lim, Stephen; Ezzati, Majid; Mozaffarian, Dariush

2015-01-01

Background Sugar-sweetened beverages (SSBs) are consumed globally and contribute to adiposity. However, the worldwide impact of SSBs on burdens of adiposity-related cardiovascular diseases (CVD), cancers, and diabetes has not been assessed by nation, age, and sex. Methods and Results We modeled global, regional, and national burdens of disease associated with SSB consumption by age/sex in 2010. Data on SSB consumption levels were pooled from national dietary surveys worldwide. The effects of SSB intake on BMI and diabetes, and of elevated BMI on CVD, diabetes, and cancers were derived from large prospective cohort pooling studies. Disease-specific mortality/morbidity data were obtained from Global Burden of Diseases, Injuries, and Risk Factors 2010 Study. We computed cause-specific population-attributable fractions for SSB consumption, which were multiplied by cause-specific mortality/morbidity to compute estimates of SSB-attributable death/disability. Analyses were done by country/age/sex; uncertainties of all input data were propagated into final estimates. Worldwide, the model estimated 184,000(95%UI=161,000–208,000) deaths/year attributable to SSB consumption: 133,000(126,000–139,000) from diabetes, 45,000(26,000–61,000) from CVD, and 6,450(4,300–8,600) from cancers. 5.0% of SSB-related deaths occurred in low-income, 70.9% in middle-income, and 24.1% in high-income countries. Proportional mortality due to SSBs ranged from <1% in Japanese >65y to 30% in Mexicans <45y. Among the 20 most populous countries, Mexico had largest absolute (405 deaths/million adults) and proportional (12.1%) deaths from SSBs. A total of 8.5(2.8, 19.2) million disability-adjusted life years (DALYs) were related to SSB intake (4.5% of diabetes-related DALYs). Conclusions SSBs, are a single, modifiable component of diet, that can impact preventable death/disability in adults in high, middle, and low-income countries, indicating an urgent need for strong global prevention programs. PMID:26124185

Temperature dependence of the LO phonon sidebands in free exciton emission of GaN

NASA Astrophysics Data System (ADS)

Xu, S. J.; Li, G. Q.; Xiong, S.-J.; Che, C. M.

2006-04-01

Temperature-dependent radiative recombination of free excitons involving one or two LO phonons in GaN is investigated in detail. It is found that both phonon sidebands possess asymmetric lineshapes and their energy spacings from the zero-phonon line strongly deviate from the characteristic energy of LO phonons as the temperature increases. Furthermore, the deviation rates of one- and two-phonon sidebands are significantly different. Segall-Mahan [Phys. Rev. 171, 935 (1968)] theory, taking the exciton-photon and exciton-phonon interactions into account, is employed to calculate the sidebands of one or two LO phonons for free excitons in a wide temperature range. Excellent agreement between the theory and experiment is achieved by using only one adjustable parameter, which leads to determination of the effective mass of heavy holes (~0.5m0).

Network models of frequency modulated sweep detection.

PubMed

Skorheim, Steven; Razak, Khaleel; Bazhenov, Maxim

2014-01-01

Frequency modulated (FM) sweeps are common in species-specific vocalizations, including human speech. Auditory neurons selective for the direction and rate of frequency change in FM sweeps are present across species, but the synaptic mechanisms underlying such selectivity are only beginning to be understood. Even less is known about mechanisms of experience-dependent changes in FM sweep selectivity. We present three network models of synaptic mechanisms of FM sweep direction and rate selectivity that explains experimental data: (1) The 'facilitation' model contains frequency selective cells operating as coincidence detectors, summing up multiple excitatory inputs with different time delays. (2) The 'duration tuned' model depends on interactions between delayed excitation and early inhibition. The strength of delayed excitation determines the preferred duration. Inhibitory rebound can reinforce the delayed excitation. (3) The 'inhibitory sideband' model uses frequency selective inputs to a network of excitatory and inhibitory cells. The strength and asymmetry of these connections results in neurons responsive to sweeps in a single direction of sufficient sweep rate. Variations of these properties, can explain the diversity of rate-dependent direction selectivity seen across species. We show that the inhibitory sideband model can be trained using spike timing dependent plasticity (STDP) to develop direction selectivity from a non-selective network. These models provide a means to compare the proposed synaptic and spectrotemporal mechanisms of FM sweep processing and can be utilized to explore cellular mechanisms underlying experience- or training-dependent changes in spectrotemporal processing across animal models. Given the analogy between FM sweeps and visual motion, these models can serve a broader function in studying stimulus movement across sensory epithelia.

Space Studies Board Annual Report 2012

NASA Technical Reports Server (NTRS)

2013-01-01

The Space Studies Board (SSB) was established in 1958 to serve as the focus of the interests and responsibilities in space research for the National Academies. The SSB provides an independent, authoritative forum for information and advice on all aspects of space science and applications, and it serves as the focal point within the National Academies for activities on space research. It oversees advisory studies and program assessments, facilitates international research coordination, and promotes communications on space science and science policy between the research community, the federal government, and the interested public. The SSB also serves as the U.S. National Committee for the International Council for Science Committee on Space Research (COSPAR). The present volume reviews the organization, activities, and reports of the SSB for the year 2012.

Development of digital sideband separating down-conversion for Yuan-Tseh Lee Array

NASA Astrophysics Data System (ADS)

Li, Chao-Te; Kubo, Derek; Cheng, Jen-Chieh; Kuroda, John; Srinivasan, Ranjani; Ho, Solomon; Guzzino, Kim; Chen, Ming-Tang

2016-07-01

This report presents a down-conversion method involving digital sideband separation for the Yuan-Tseh Lee Array (YTLA) to double the processing bandwidth. The receiver consists of a MMIC HEMT LNA front end operating at a wavelength of 3 mm, and sub-harmonic mixers that output signals at intermediate frequencies (IFs) of 2-18 GHz. The sideband separation scheme involves an analog 90° hybrid followed by two mixers that provide down-conversion of the IF signal to a pair of in-phase (I) and quadrature (Q) signals in baseband. The I and Q baseband signals are digitized using 5 Giga sample per second (Gsps) analog-to-digital converters (ADCs). A second hybrid is digitally implemented using field-programmable gate arrays (FPGAs) to produce two sidebands, each with a bandwidth of 1.6 GHz. The 2 x 1.6 GHz band can be tuned to cover any 3.6 GHz window within the aforementioned IF range of the array. Sideband rejection ratios (SRRs) above 20 dB can be obtained across the 3.6 GHz bandwidth by equalizing the power and delay between the I and Q baseband signals. Furthermore, SRRs above 30 dB can be achieved when calibration is applied.

Averting Obesity and Type 2 Diabetes in India through Sugar-Sweetened Beverage Taxation: An Economic-Epidemiologic Modeling Study

PubMed Central

Basu, Sanjay; Vellakkal, Sukumar; Agrawal, Sutapa; Stuckler, David; Popkin, Barry; Ebrahim, Shah

2014-01-01

Background Taxing sugar-sweetened beverages (SSBs) has been proposed in high-income countries to reduce obesity and type 2 diabetes. We sought to estimate the potential health effects of such a fiscal strategy in the middle-income country of India, where there is heterogeneity in SSB consumption, patterns of substitution between SSBs and other beverages after tax increases, and vast differences in chronic disease risk within the population. Methods and Findings Using consumption and price variations data from a nationally representative survey of 100,855 Indian households, we first calculated how changes in SSB price alter per capita consumption of SSBs and substitution with other beverages. We then incorporated SSB sales trends, body mass index (BMI), and diabetes incidence data stratified by age, sex, income, and urban/rural residence into a validated microsimulation of caloric consumption, glycemic load, overweight/obesity prevalence, and type 2 diabetes incidence among Indian subpopulations facing a 20% SSB excise tax. The 20% SSB tax was anticipated to reduce overweight and obesity prevalence by 3.0% (95% CI 1.6%–5.9%) and type 2 diabetes incidence by 1.6% (95% CI 1.2%–1.9%) among various Indian subpopulations over the period 2014–2023, if SSB consumption continued to increase linearly in accordance with secular trends. However, acceleration in SSB consumption trends consistent with industry marketing models would be expected to increase the impact efficacy of taxation, averting 4.2% of prevalent overweight/obesity (95% CI 2.5–10.0%) and 2.5% (95% CI 1.0–2.8%) of incident type 2 diabetes from 2014–2023. Given current consumption and BMI distributions, our results suggest the largest relative effect would be expected among young rural men, refuting our a priori hypothesis that urban populations would be isolated beneficiaries of SSB taxation. Key limitations of this estimation approach include the assumption that consumer expenditure behavior from prior years, captured in price elasticities, will reflect future behavior among consumers, and potential underreporting of consumption in dietary recall data used to inform our calculations. Conclusion Sustained SSB taxation at a high tax rate could mitigate rising obesity and type 2 diabetes in India among both urban and rural subpopulations. Please see later in the article for the Editors' Summary PMID:24409102

Sugar-sweetened beverage intake and cardiovascular risk factor profile in youth with type 1 diabetes: application of measurement error methodology in the SEARCH Nutrition Ancillary Study.

PubMed

Liese, Angela D; Crandell, Jamie L; Tooze, Janet A; Kipnis, Victor; Bell, Ronny; Couch, Sarah C; Dabelea, Dana; Crume, Tessa L; Mayer-Davis, Elizabeth J

2015-08-14

The SEARCH Nutrition Ancillary Study aims to investigate the role of dietary intake on the development of long-term complications of type 1 diabetes in youth, and capitalise on measurement error (ME) adjustment methodology. Using the National Cancer Institute (NCI) method for episodically consumed foods, we evaluated the relationship between sugar-sweetened beverage (SSB) intake and cardiovascular risk factor profile, with the application of ME adjustment methodology. The calibration sample included 166 youth with two FFQ and three 24 h dietary recall data within 1 month. The full sample included 2286 youth with type 1 diabetes. SSB intake was significantly associated with higher TAG, total and LDL-cholesterol concentrations, after adjusting for energy, age, diabetes duration, race/ethnicity, sex and education. The estimated effect size was larger (model coefficients increased approximately 3-fold) after the application of the NCI method than without adjustment for ME. Compared with individuals consuming one serving of SSB every 2 weeks, those who consumed one serving of SSB every 2 d had 3.7 mg/dl (0.04 mmol/l) higher TAG concentrations and 4.0 mg/dl (0.10 mmol/l) higher total cholesterol and LDL-cholesterol concentrations, after adjusting for ME and covariates. SSB intake was not associated with measures of adiposity and blood pressure. Our findings suggest that SSB intake is significantly related to increased lipid levels in youth with type 1 diabetes, and that estimates of the effect size of SSB on lipid levels are severely attenuated in the presence of ME. Future studies in youth with diabetes should consider a design that will allow for the adjustment for ME when studying the influence of diet on health status.

Sugar-Sweetened Beverage Consumption Is Associated With Change of Visceral Adipose Tissue Over 6 Years of Follow-Up.

PubMed

Ma, Jiantao; McKeown, Nicola M; Hwang, Shih-Jen; Hoffmann, Udo; Jacques, Paul F; Fox, Caroline S

2016-01-26

Sugar-sweetened beverage (SSB) intake has been linked to abnormal abdominal adipose tissue. We examined the prospective association of habitual SSB intake and change in visceral adipose tissue (VAT) and subcutaneous adipose tissue. The quantity (volume, cm(3)) and quality (attenuation, Hounsfield Unit) of abdominal adipose tissue were measured using computed tomography in 1003 participants (mean age 45.3 years, 45.0% women) at examination 1 and 2 in the Framingham's Third Generation cohort. The 2 exams were ≈ 6 years apart. At baseline, SSB and diet soda intake were assessed using a valid food frequency questionnaire. Participants were categorized into 4 groups: none to <1 serving/mo (nonconsumers), 1 serving/mo to <1 serving/week, 1 serving/week to 1 serving/d, and ≥ 1 serving/d (daily consumers) of either SSB or diet soda. After adjustment for multiple confounders including change in body weight, higher SSB intake was associated with greater change in VAT volume (P trend<0.001). VAT volume increased by 658 cm(3) (95% confidence interval [CI], 602 to 713), 649 cm(3) (95% CI, 582 to 716), 707 cm(3) (95% CI, 657 to 757), and 852 cm(3) (95% CI, 760 to 943) from nonconsumers to daily consumers. Higher SSB intake was also associated with greater decline of VAT attenuation (P trend=0.007); however, the association became nonsignificant after additional adjustment for VAT volume change. In contrast, diet soda consumption was not associated with change in abdominal adipose tissue. Regular SSB intake was associated with adverse change in both VAT quality and quantity, whereas we observed no such association for diet soda. © 2016 American Heart Association, Inc.

The Relationship of Perceptions of Tap Water Safety with Intake of Sugar Sweetened Beverages and Plain Water among U.S. Adults

PubMed Central

Onufrak, Stephen J; Park, Sohyun; Sharkey, Joseph R; Sherry, Bettylou

2015-01-01

Objective Research is limited on whether mistrust of tap water discourages plain water intake and leads to greater intake of sugar-sweetened beverages (SSB). The objective of this study is to examine demographic differences in perceptions of tap water safety and determine if these perceptions are associated with intake of SSB and plain water Design The study examined perceptions of tap water safety and their cross-sectional association with intake of SSB and plain water. Racial/ethnic differences in the associations of tap water perceptions with SSB and plain water intake were also examined. Setting Nationally weighted data from 2010 HealthStyles Survey (n=4184) Subjects United States adults ≥18 years Results Overall, 13.0% of participants disagreed that their local tap water was safe to drink and 26.4% of participants agreed that bottled water was safer than tap water. Both mistrust of tap water safety and favoring bottled water differed by region, age, race/ethnicity, income, and education. The associations of tap water mistrust on intake of SSB and plain water were modified by race/ethnicity (p<0.05). Non-white racial/ethnic groups who disagreed that their local tap water was safe to drink were more likely to report low intake of plain water. The odds of consuming ≥1 SSB/day among Hispanics who mistrusted their local tap water was twice that of Hispanics who did not (OR = 2.0; 95% CI: 1.2, 3.3). Conclusions Public health efforts to promote healthy beverages should recognize the potential impact of tap water perceptions on water and SSB intake among minority populations. PMID:23098620

Sugar-Sweetened Beverage Consumption is Associated With Change of Visceral Adipose Tissue Over 6 Years of Follow-Up

PubMed Central

Ma, Jiantao; McKeown, Nicola M.; Hwang, Shih-Jen; Hoffmann, Udo; Jacques, Paul F.; Fox, Caroline S.

2015-01-01

Background Sugar-sweetened beverage (SSB) intake has been linked to abnormal abdominal adipose tissue. We examined the prospective association of habitual SSB intake and change in visceral adipose tissue (VAT) and subcutaneous adipose tissue (SAT). Methods and Results The quantity (volume, cm3) and quality (attenuation, Hounsfield Unit) of abdominal adipose tissue were measured using computed tomography in 1,003 participants (mean age 45.3 years, 45.0% women) at exam 1 and 2 in the Framingham’s Third Generation cohort. The 2 exams were approximately 6 years apart. At baseline, SSB and diet soda intake were assessed using a valid food frequency questionnaire. Participants were categorized into 4 groups: none to <1 serving/month (non-consumers), 1 serving/month to <1 serving/week, 1 serving/week to 1 serving/day, and ≥1 serving/day (daily consumers) of either SSB or diet soda. After adjustment for multiple confounders including change in body weight, higher SSB intake was associated with greater change in VAT volume (P-trend<0.001). VAT volume increased by 658 cm3 (95%CI: 602–713), 649 cm3 (95%CI: 582–716), 707 cm3 (95%CI: 657–757), and 852 cm3 (95%CI: 760–943) from non-consumers to daily consumers. Higher SSB intake was also associated with greater decline of VAT attenuation (P-trend=0.007); however, the association became non-significant after additional adjustment for VAT volume change. In contrast, diet soda consumption was not associated with change in abdominal adipose tissue. Conclusions Regular SSB intake was associated with adverse change in both VAT quality and quantity, whereas we observed no such association for diet soda. PMID:26755505

Sugar-sweetened beverages and dental caries in adults: a 4-year prospective study.

PubMed

Bernabé, Eduardo; Vehkalahti, Miira M; Sheiham, Aubrey; Aromaa, Arpo; Suominen, Anna L

2014-08-01

To explore the association between frequency of consumption of sugar-sweetened beverages (SSB) and caries increment over 4 years in adults. A second objective was to explore whether the association between frequency of SSB consumption and caries increment varied by socio-demographic characteristics and use of fluoride toothpaste. Data from 939 dentate adults who participated in both the Health 2000 Survey and the Follow-Up Study of Finnish Adults' Oral Health were analysed. At baseline, participants provided information on demographic characteristics, education and dental behaviours, including two questions on frequency of SSB consumption. The 4-year net DMFT increment was calculated using data from baseline and follow-up clinical oral examinations. The association was tested in negative binomial regression models and the moderating role of sex, age, education and use of fluoride toothpaste was examined by adding their two-way interaction with SSB consumption to the main effects model. A positive association was found between frequency of SBS consumption and 4-year net DMFT increment, regardless of participants' socio-demographic and behavioural characteristics. Adults drinking 1-2 and 3+ SSB daily had, respectively, 31% (Incidence Rate Ratio: 1.31; 95%CI: 1.02-1.67) and 33% (IRR: 1.33; 95%CI; 1.03-1.72) greater net DMFT increments than those not drinking any SSB. None of the four two-way interaction terms was significant (all p>0.05). There seems to be a dose-response relationship between frequency of SSB consumption and caries increment in adults. That association was consistent across socio-demographic characteristics, and more importantly, use of fluoride toothpaste. Drinking sugar-sweetened beverages on a daily basis is related to greater caries risk in adults. Copyright © 2014 Elsevier Ltd. All rights reserved.

Structural equation modeling of the associations between the home environment and obesity-related cardiovascular fitness and insulin resistance among Hispanic children.

PubMed

Santiago-Torres, Margarita; Cui, Yuchen; Adams, Alexandra K; Allen, David B; Carrel, Aaron L; Guo, Jessica Y; LaRowe, Tara L; Schoeller, Dale A

2016-06-01

Hispanic children are disproportionally affected by obesity-related risk of metabolic disease. We used the structural equation modeling to examine the associations between specific diet and physical activity (PA) behaviors at home and Hispanic children's metabolic health. A total of 187 Hispanic children and their parents from an urban community in Wisconsin participated in the study. Exposure variables included, children's daily intake of sugar-sweetened beverages (SSB) and PA; home availability of SSB and PA areas/equipment; and parents' intake of SSB and PA, assessed through self-administered questionnaires. Outcome variables for children's metabolic health included, measured anthropometrics; cardiovascular fitness assessed using the Progressive Aerobic Cardiovascular Endurance Run (PACER); and insulin resistance determined with the homeostasis model assessment of insulin resistance (HOMAIR). We found that children's daily intake of SSB was positively associated with BMI z-score, which in turn, was positively associated with HOMAIR (P < 0.05). Specific diet behaviors at home associated with children's intake of SSB, included home availability of SSB, which mediated the association between parents' and children's intake of SSB (P < 0.05). Children's PA was positively associated with PACER z-score, which in turn, was inversely associated with HOMAIR (P < 0.05). Specific PA behaviors at home associated with children's PA, included home availability of PA areas/equipment, which mediated the association between parents' and children's PA (P < 0.05). The structural equation model indices suggested a satisfactory model fit (Chi-square, X(2) = 53.1, comparative fix index = 0.92, root-mean-squared error associated = 0.04). The findings confirm the need for interventions at the family level that promotes healthier home environments by targeting poor diet and low levels of PA in all family members. Published by Elsevier Ltd.

Sak4 of Phage HK620 Is a RecA Remote Homolog With Single-Strand Annealing Activity Stimulated by Its Cognate SSB Protein.

PubMed

Hutinet, Geoffrey; Besle, Arthur; Son, Olivier; McGovern, Stephen; Guerois, Raphaël; Petit, Marie-Agnès; Ochsenbein, Françoise; Lecointe, François

2018-01-01

Bacteriophages are remarkable for the wide diversity of proteins they encode to perform DNA replication and homologous recombination. Looking back at these ancestral forms of life may help understanding how similar proteins work in more sophisticated organisms. For instance, the Sak4 family is composed of proteins similar to the archaeal RadB protein, a Rad51 paralog. We have previously shown that Sak4 allowed single-strand annealing in vivo , but only weakly compared to the phage λ Redβ protein, highlighting putatively that Sak4 requires partners to be efficient. Here, we report that the purified Sak4 of phage HK620 infecting Escherichia coli is a poorly efficient annealase on its own. A distant homolog of SSB, which gene is usually next to the sak4 gene in various species of phages, highly stimulates its recombineering activity in vivo. In vitro , Sak4 binds single-stranded DNA and performs single-strand annealing in an ATP-dependent way. Remarkably, the single-strand annealing activity of Sak4 is stimulated by its cognate SSB. The last six C-terminal amino acids of this SSB are essential for the binding of Sak4 to SSB-covered single-stranded DNA, as well as for the stimulation of its annealase activity. Finally, expression of sak4 and ssb from HK620 can promote low-level of recombination in vivo , though Sak4 and its SSB are unable to promote strand exchange in vitro . Regarding its homology with RecA, Sak4 could represent a link between two previously distinct types of recombinases, i.e., annealases that help strand exchange proteins and strand exchange proteins themselves.

Analysis of Heat-Labile Sites Generated by Reactions of Depleted Uranium and Ascorbate in Plasmid DNA

PubMed Central

Wilson, Janice; Young, Ashley; Civitello, Edgar R.

2013-01-01

The goal of this study was to characterize how depleted uranium (DU) causes DNA damage. Procedures were developed to assess the ability of organic and inorganic DNA adducts to convert to single strand breaks (SSB) in pBR322 plasmid DNA in the presence of heat or piperidine. DNA adducts formed by methyl methanesulfonate (MMS), cis-platin (cis-Pt), and chromic chloride were compared to those formed by reaction of uranyl acetate (UA) and ascorbate (Asc). Uranyl ion in the presence of Asc produced U-DNA adducts that converted to SSB upon heating. Piperidine, which acted on DNA methylated by MMS to convert methyl-DNA adducts to SSB, served in the opposite fashion with U-DNA adducts by decreasing SSB. The observation that piperidine also decreased the gel shift for metal-DNA adducts formed by monofunctional cis-Pt and chromic chloride was interpreted to suggest that piperidine served to remove U-DNA adducts. Radical scavengers did not affect formation of U-induced SSB, suggesting that SSB arose from the presence of U-DNA adducts and not from free radicals. A model is proposed to predict how U-DNA adducts may serve as initial lesions that convert to SSB or AP sites. Results suggest that DU can act as a chemical genotoxin that does not require radiation for its mode of action. Characterizing the DNA lesions formed by DU is necessary to assess the relative importance of different DNA lesions in the formation of DU-induced mutations. Understanding mechanisms of formation of DU-induced mutations may contribute to identification of biomarkers of DU exposures in humans. PMID:24218036

Sak4 of Phage HK620 Is a RecA Remote Homolog With Single-Strand Annealing Activity Stimulated by Its Cognate SSB Protein

PubMed Central

Hutinet, Geoffrey; Besle, Arthur; Son, Olivier; McGovern, Stephen; Guerois, Raphaël; Petit, Marie-Agnès; Ochsenbein, Françoise; Lecointe, François

2018-01-01

Bacteriophages are remarkable for the wide diversity of proteins they encode to perform DNA replication and homologous recombination. Looking back at these ancestral forms of life may help understanding how similar proteins work in more sophisticated organisms. For instance, the Sak4 family is composed of proteins similar to the archaeal RadB protein, a Rad51 paralog. We have previously shown that Sak4 allowed single-strand annealing in vivo, but only weakly compared to the phage λ Redβ protein, highlighting putatively that Sak4 requires partners to be efficient. Here, we report that the purified Sak4 of phage HK620 infecting Escherichia coli is a poorly efficient annealase on its own. A distant homolog of SSB, which gene is usually next to the sak4 gene in various species of phages, highly stimulates its recombineering activity in vivo. In vitro, Sak4 binds single-stranded DNA and performs single-strand annealing in an ATP-dependent way. Remarkably, the single-strand annealing activity of Sak4 is stimulated by its cognate SSB. The last six C-terminal amino acids of this SSB are essential for the binding of Sak4 to SSB-covered single-stranded DNA, as well as for the stimulation of its annealase activity. Finally, expression of sak4 and ssb from HK620 can promote low-level of recombination in vivo, though Sak4 and its SSB are unable to promote strand exchange in vitro. Regarding its homology with RecA, Sak4 could represent a link between two previously distinct types of recombinases, i.e., annealases that help strand exchange proteins and strand exchange proteins themselves. PMID:29740405

Reduced availability of sugar-sweetened beverages and diet soda has a limited impact on beverage consumption patterns in Maine high school youth.

PubMed

Blum, Janet E Whatley; Davee, Anne-Marie; Beaudoin, Christina M; Jenkins, Paul L; Kaley, Lori A; Wigand, Debra A

2008-01-01

To examine change in high school students' beverage consumption patterns pre- and post-intervention of reduced availability of sugar-sweetened beverages (SSB) and diet soda in school food venues. A prospective, quasi-experimental, nonrandomized study design. Public high schools. A convenience sample from control (n = 221) and intervention (n = 235) high schools. Schools aimed to reduce (n = 4) or not change (n = 3) availability of SSB and diet soda in food venues for 1 school year. Subjects' beverage servings/day was determined from a food frequency questionnaire pre- and post-intervention. Two-by-two mixed analysis of variance model compared pre- to post-intervention servings/day between control and intervention subjects, stratified by gender. Consumption of SSB decreased in both intervention and control boys (F = 53.69, P < .05) and girls (F = 22.87, P < .05). Intervention girls decreased diet soda consumption as compared to control girls (F = 6.57, P < .05). Reducing availability of SSB in schools did not result in a greater decrease in SSB consumption by intervention as compared to control subjects. The impact of reducing availability of SSB at school may be limited. A better understanding of beverage consumption patterns may be needed to determine the efficacy of school food policies on those youth susceptible to obesity.

Effectiveness of HIV/STD Sexual Risk Reduction Groups for Women in Substance Abuse Treatment Programs: Results of a NIDA Clinical Trials Network Trial

PubMed Central

Tross, Susan; Campbell, Aimee N. C.; Cohen, Lisa R.; Calsyn, Donald; Pavlicova, Martina; Miele, Gloria; Hu, Mei-Chen; Haynes, Louise; Nugent, Nancy; Gan, Weijin; Hatch-Maillette, Mary; Mandler, Raul; McLaughlin, Paul; El-Bassel, Nabila; Crits-Christoph, Paul; Nunes, Edward V.

2009-01-01

Context Since drug-involved women are among the fastest growing groups with AIDS, sexual risk reduction intervention for them is a public health imperative. Objective Test effectiveness of HIV/STD safer sex skills building (SSB) groups for women in community drug treatment. Design Randomized trial of SSB versus standard HIV/STD Education (HE); assessments at baseline, 3- and 6- months Participants Women recruited from 12 methadone or psychosocial treatment programs in NIDA’s Clinical Trials Network. 515 women with ≥ one unprotected vaginal or anal sex occasion (USO) with a male partner in the past 6 months were randomized. Interventions In SSB, five 90-minute groups used problem-solving and skills rehearsal to increase HIV/STD risk awareness, condom use and partner negotiation skills. In HE, one 60-minute group covered HIV/STD disease, testing, treatment, and prevention information. Main Outcome Number of USOs at follow up. Results A significant difference in mean USOs was obtained between SSB and HE over time (F=67.2, p<.0001). At 3 months, significant decrements were observed in both conditions. At 6 months SSB maintained the decrease, HE returned to baseline (p<.0377). Women in SSB had 29% fewer USOs than those in HE. Conclusions Skills building interventions can produce ongoing sexual risk reduction in women in community drug treatment. PMID:18645513

Targeting Overconsumption of Sugar-Sweetened Beverages vs. Overall Poor Diet Quality for Cardiometabolic Diseases Risk Prevention: Place Your Bets!

PubMed Central

Arsenault, Benoit J.; Lamarche, Benoît; Després, Jean-Pierre

2017-01-01

Chronic overconsumption of sugar-sweetened beverages (SSBs) is amongst the dietary factors most consistently found to be associated with obesity, type 2 diabetes (T2D) and cardiovascular disease (CVD) risk in large epidemiological studies. Intervention studies have shown that SSB overconsumption increases intra-abdominal obesity and ectopic lipid deposition in the liver, and also exacerbates cardiometabolic risk. Similar to the prevalence of obesity and T2D, national surveys of food consumption have shown that chronic overconsumption of SSBs is skyrocketing in many parts of the world, yet with marked heterogeneity across countries. SSB overconsumption is also particularly worrisome among children and adolescents. Although the relationships between SSB overconsumption and obesity, T2D, and CVD are rather consistent in epidemiological studies, it has also been shown that SSB overconsumption is part of an overall poor dietary pattern and is particularly prevalent among subgroups of the population with low socioeconomic status, thereby questioning the major focus on SSBs to target/prevent cardiometabolic diseases. Public health initiatives aimed specifically at decreasing SSB overconsumption will most likely be successful in influencing SSB consumption per se. However, comprehensive strategies targeting poor dietary patterns and aiming at improving global dietary quality are likely to have much more impact in addressing the unprecedented public health challenges that we are currently facing. PMID:28608806

Targeting Overconsumption of Sugar-Sweetened Beverages vs. Overall Poor Diet Quality for Cardiometabolic Diseases Risk Prevention: Place Your Bets!

PubMed

Arsenault, Benoit J; Lamarche, Benoît; Després, Jean-Pierre

2017-06-13

Chronic overconsumption of sugar-sweetened beverages (SSBs) is amongst the dietary factors most consistently found to be associated with obesity, type 2 diabetes (T2D) and cardiovascular disease (CVD) risk in large epidemiological studies. Intervention studies have shown that SSB overconsumption increases intra-abdominal obesity and ectopic lipid deposition in the liver, and also exacerbates cardiometabolic risk. Similar to the prevalence of obesity and T2D, national surveys of food consumption have shown that chronic overconsumption of SSBs is skyrocketing in many parts of the world, yet with marked heterogeneity across countries. SSB overconsumption is also particularly worrisome among children and adolescents. Although the relationships between SSB overconsumption and obesity, T2D, and CVD are rather consistent in epidemiological studies, it has also been shown that SSB overconsumption is part of an overall poor dietary pattern and is particularly prevalent among subgroups of the population with low socioeconomic status, thereby questioning the major focus on SSBs to target/prevent cardiometabolic diseases. Public health initiatives aimed specifically at decreasing SSB overconsumption will most likely be successful in influencing SSB consumption per se. However, comprehensive strategies targeting poor dietary patterns and aiming at improving global dietary quality are likely to have much more impact in addressing the unprecedented public health challenges that we are currently facing.

Effectiveness of HIV/STD sexual risk reduction groups for women in substance abuse treatment programs: results of NIDA Clinical Trials Network Trial.

PubMed

Tross, Susan; Campbell, Aimee N C; Cohen, Lisa R; Calsyn, Donald; Pavlicova, Martina; Miele, Gloria M; Hu, Mei-Chen; Haynes, Louise; Nugent, Nancy; Gan, Weijin; Hatch-Maillette, Mary; Mandler, Raul; McLaughlin, Paul; El-Bassel, Nabila; Crits-Christoph, Paul; Nunes, Edward V

2008-08-15

Because drug-involved women are among the fastest growing groups with AIDS, sexual risk reduction intervention for them is a public health imperative. To test effectiveness of HIV/STD safer sex skills building (SSB) groups for women in community drug treatment. Randomized trial of SSB versus standard HIV/STD Education (HE); assessments at baseline, 3 and 6 months. Women recruited from 12 methadone or psychosocial treatment programs in Clinical Trials Network of National Institute on Drug Abuse. Five hundred fifteen women with >or=1 unprotected vaginal or anal sex occasion (USO) with a male partner in the past 6 months were randomized. In SSB, five 90-minute groups used problem solving and skills rehearsal to increase HIV/STD risk awareness, condom use, and partner negotiation skills. In HE, one 60-minute group covered HIV/STD disease, testing, treatment, and prevention information. Number of USOs at follow-up. A significant difference in mean USOs was obtained between SSB and HE over time (F = 67.2, P < 0.0001). At 3 months, significant decrements were observed in both conditions. At 6 months, SSB maintained the decrease and HE returned to baseline (P < 0.0377). Women in SSB had 29% fewer USOs than those in HE. Skills building interventions can produce ongoing sexual risk reduction in women in community drug treatment.

Saccharomyces cerevisiae SSB1 protein and its relationship to nucleolar RNA-binding proteins.

PubMed Central

Jong, A Y; Clark, M W; Gilbert, M; Oehm, A; Campbell, J L

1987-01-01

To better define the function of Saccharomyces cerevisiae SSB1, an abundant single-stranded nucleic acid-binding protein, we determined the nucleotide sequence of the SSB1 gene and compared it with those of other proteins of known function. The amino acid sequence contains 293 amino acid residues and has an Mr of 32,853. There are several stretches of sequence characteristic of other eucaryotic single-stranded nucleic acid-binding proteins. At the amino terminus, residues 39 to 54 are highly homologous to a peptide in calf thymus UP1 and UP2 and a human heterogeneous nuclear ribonucleoprotein. Residues 125 to 162 constitute a fivefold tandem repeat of the sequence RGGFRG, the composition of which suggests a nucleic acid-binding site. Near the C terminus, residues 233 to 245 are homologous to several RNA-binding proteins. Of 18 C-terminal residues, 10 are acidic, a characteristic of the procaryotic single-stranded DNA-binding proteins and eucaryotic DNA- and RNA-binding proteins. In addition, examination of the subcellular distribution of SSB1 by immunofluorescence microscopy indicated that SSB1 is a nuclear protein, predominantly located in the nucleolus. Sequence homologies and the nucleolar localization make it likely that SSB1 functions in RNA metabolism in vivo, although an additional role in DNA metabolism cannot be excluded. Images PMID:2823109

Improvement of lactic acid production in Saccharomyces cerevisiae by a deletion of ssb1.

PubMed

Lee, Jinsuk J; Crook, Nathan; Sun, Jie; Alper, Hal S

2016-01-01

Polylactic acid (PLA) is an important renewable polymer, but current processes for producing its precursor, lactic acid, suffer from process inefficiencies related to the use of bacterial hosts. Therefore, improving the capacity of Saccharomyces cerevisiae to produce lactic acid is a promising approach to improve industrial production of lactic acid. As one such improvement required, the lactic acid tolerance of yeast must be significantly increased. To enable improved tolerance, we employed an RNAi-mediated genome-wide expression knockdown approach as a means to rapidly identify potential genetic targets. In this approach, several gene knockdown targets were identified which confer increased acid tolerance to S. cerevisiae BY4741, of which knockdown of the ribosome-associated chaperone SSB1 conferred the highest increase (52%). This target was then transferred into a lactic acid-overproducing strain of S. cerevisiae CEN.PK in the form of a knockout and the resulting strain demonstrated up to 33% increased cell growth, 58% increased glucose consumption, and 60% increased L-lactic acid production. As SSB1 contains a close functional homolog SSB2 in yeast, this result was counterintuitive and may point to as-yet-undefined functional differences between SSB1 and SSB2 related to lactic acid production. The final strain produced over 50 g/L of lactic acid in under 60 h of fermentation.

A Multicomponent Intervention Helped Reduce Sugar-Sweetened Beverage Intake in Economically Disadvantaged Hispanic Children.

PubMed

Feng, Du; Song, Huaxin; Esperat, M Christina; Black, Ipuna

2016-11-01

This study aimed to examine the effect of a multicomponent intervention program on consumption of sugar-sweetened beverages (SSBs), and lifestyle factors associated with SSB intake, in Hispanic children from low-income families. A five-wave longitudinal study using a quasi-experimental design was conducted. Five elementary schools in West Texas served as the setting. Participants included 555 predominantly Hispanic children (ages 5-9 years) from low-income families and their parents (n = 525). A multicomponent intervention program was implemented. Children's anthropometric measures were obtained. Their weight status was determined based on body mass index for age and gender. Parents responded to a demographic questionnaire, a shelf inventory, an acculturation scale, and a family survey. Growth curve analyses were used to test differences between intervention and comparison participants' SSB intake and to examine potential covariates. Comparison group children's daily SSB intake significantly increased over time (B = 1.06 ± .40 ounces per month, p < .01), but this linear increase of SSB was slowed down by the intervention (B = -.29 ± .12, p < .05). More daily TV time, more fast food intake, and more types of SSBs available at home were associated with higher SSB intake. Risk factors of childhood obesity were associated with each other. The intervention program produced a modest reduction in SSB consumed by economically disadvantaged and predominantly Hispanic children. © 2016 by American Journal of Health Promotion, Inc.

School beverage environment and children's energy expenditure associated with physical education class: an agent-based model simulation.

PubMed

Chen, H-J; Xue, H; Kumanyika, S; Wang, Y

2017-06-01

Physical activity contributes to children's energy expenditure and prevents excess weight gain, but fluid replacement with sugar-sweetened beverages (SSBs) may diminish this benefit. The aim of this study was to explore the net energy expenditure (EE) after physical education (PE) class given the competition between water and SSB consumption for rehydration and explore environmental factors that may influence the net EE, e.g. PE duration, affordability of SSB and students' SSB preference. We built an agent-based model that simulates the behaviour of 13-year-old children in a PE class with nearby water fountains and SSB vending machines available. A longer PE class contributed to greater prevalence of dehydration and required more time for rehydration. The energy cost of a PE class with activity intensity equivalent to 45 min of jogging is about 300 kcal on average, i.e. 10-15% of average 13-year-old children's total daily EE. Adding an SSB vending machine could offset PE energy expenditure by as much as 90 kcal per child, which was associated with PE duration, students' pocket money and SSB preference. Sugar-sweetened beverage vending machines in school may offset some of the EE in PE classes. This could be avoided if water is the only readily available source for children's fluid replacement after class. © 2016 World Obesity Federation.

Acceptance threshold theory can explain occurrence of homosexual behaviour.

PubMed

Engel, Katharina C; Männer, Lisa; Ayasse, Manfred; Steiger, Sandra

2015-01-01

Same-sex sexual behaviour (SSB) has been documented in a wide range of animals, but its evolutionary causes are not well understood. Here, we investigated SSB in the light of Reeve's acceptance threshold theory. When recognition is not error-proof, the acceptance threshold used by males to recognize potential mating partners should be flexibly adjusted to maximize the fitness pay-off between the costs of erroneously accepting males and the benefits of accepting females. By manipulating male burying beetles' search time for females and their reproductive potential, we influenced their perceived costs of making an acceptance or rejection error. As predicted, when the costs of rejecting females increased, males exhibited more permissive discrimination decisions and showed high levels of SSB; when the costs of accepting males increased, males were more restrictive and showed low levels of SSB. Our results support the idea that in animal species, in which the recognition cues of females and males overlap to a certain degree, SSB is a consequence of an adaptive discrimination strategy to avoid the costs of making rejection errors. © 2015 The Author(s) Published by the Royal Society. All rights reserved.

Strategic messaging to promote taxation of sugar-sweetened beverages: lessons from recent political campaigns.

PubMed

Jou, Judy; Niederdeppe, Jeff; Barry, Colleen L; Gollust, Sarah E

2014-05-01

This study explored the use of strategic messaging by proponents of sugar-sweetened beverage (SSB) taxation to influence public opinion and shape the policy process, emphasizing the experiences in El Monte and Richmond, California, with SSB tax proposals in 2012. We conducted 18 semistructured interviews with key stakeholders about the use and perceived effectiveness of messages supporting and opposing SSB taxation, knowledge sharing among advocates, message dissemination, and lessons learned from their messaging experiences. The protax messages most frequently mentioned by respondents were reinvesting tax revenue into health-related programs and linking SSB consumption to health outcomes such as obesity and diabetes. The most frequently mentioned antitax messages addressed negative economic effects on businesses and government restriction of personal choice. Factors contributing to perceived messaging success included clearly defining "sugar-sweetened beverage" and earmarking funds for obesity prevention, incorporating cultural sensitivity into messaging, and providing education about the health effects of SSB consumption. Sugar-sweetened beverage taxation has faced significant challenges in gaining political and public support. Future campaigns can benefit from insights gained through the experiences of stakeholders involved in previous policy debates.

Improving the resolution in proton-detected through-space heteronuclear multiple quantum correlation NMR spectroscopy.

PubMed

Shen, Ming; Trébosc, J; Lafon, O; Pourpoint, F; Hu, Bingwen; Chen, Qun; Amoureux, J-P

2014-08-01

Connectivities and proximities between protons and low-gamma nuclei can be probed in solid-state NMR spectroscopy using two-dimensional (2D) proton-detected heteronuclear correlation, through Heteronuclear Multiple Quantum Correlation (HMQC) pulse sequence. The indirect detection via protons dramatically enhances the sensitivity. However, the spectra are often broadened along the indirect F1 dimension by the decay of heteronuclear multiple-quantum coherences under the strong (1)H-(1)H dipolar couplings. This work presents a systematic comparison of the performances of various decoupling schemes during the indirect t1 evolution period of dipolar-mediated HMQC (D-HMQC) experiment. We demonstrate that (1)H-(1)H dipolar decoupling sequences during t1, such as symmetry-based schemes, phase-modulated Lee-Goldburg (PMLG) and Decoupling Using Mind-Boggling Optimization (DUMBO), provide better resolution than continuous wave (1)H irradiation. We also report that high resolution requires the preservation of (1)H isotropic chemical shifts during the decoupling sequences. When observing indirectly broad spectra presenting numerous spinning sidebands, the D-HMQC sequence must be fully rotor-synchronized owing to the rotor-synchronized indirect sampling and dipolar recoupling sequence employed. In this case, we propose a solution to reduce artefact sidebands caused by the modulation of window delays before and after the decoupling application during the t1 period. Moreover, we show that (1)H-(1)H dipolar decoupling sequence using Smooth Amplitude Modulation (SAM) minimizes the t1-noise. The performances of the various decoupling schemes are assessed via numerical simulations and compared to 2D (1)H-{(13)C} D-HMQC experiments on [U-(13)C]-L-histidine⋅HCl⋅H2O at various magnetic fields and Magic Angle spinning (MAS) frequencies. Great resolution and sensitivity enhancements resulting from decoupling during t1 period enable the detection of heteronuclear correlation between aliphatic protons and ammonium (14)N sites in L-histidine⋅HCl⋅H2O. Copyright © 2014 Elsevier Inc. All rights reserved.

Employment Impact of Sugar-Sweetened Beverage Taxes

PubMed Central

Powell, Lisa M.; Wada, Roy; Persky, Joseph J.; Chaloupka, Frank J.

2014-01-01

Objectives. We assessed the impact of sugar-sweetened beverage (SSB) taxes on net employment. Methods. We used a macroeconomic simulation model to assess the employment impact of a 20% SSB tax accounting for changes in SSB demand, substitution to non-SSBs, income effects, and government expenditures of tax revenues for Illinois and California in 2012. Results. We found increased employment of 4406 jobs in Illinois and 6654 jobs in California, representing a respective 0.06% and 0.03% change in employment. Declines in employment within the beverage industry occurred but were offset by new employment in nonbeverage industry and government sectors. Conclusions. SSB taxes do not have a negative impact on state-level employment, and industry claims of regional job losses are overstated and may mislead lawmakers and constituents. PMID:24524492

Spectral negentropy based sidebands and demodulation analysis for planet bearing fault diagnosis

NASA Astrophysics Data System (ADS)

Feng, Zhipeng; Ma, Haoqun; Zuo, Ming J.

2017-12-01

Planet bearing vibration signals are highly complex due to intricate kinematics (involving both revolution and spinning) and strong multiple modulations (including not only the fault induced amplitude modulation and frequency modulation, but also additional amplitude modulations due to load zone passing, time-varying vibration transfer path, and time-varying angle between the gear pair mesh lines of action and fault impact force vector), leading to difficulty in fault feature extraction. Rolling element bearing fault diagnosis essentially relies on detection of fault induced repetitive impulses carried by resonance vibration, but they are usually contaminated by noise and therefor are hard to be detected. This further adds complexity to planet bearing diagnostics. Spectral negentropy is able to reveal the frequency distribution of repetitive transients, thus providing an approach to identify the optimal frequency band of a filter for separating repetitive impulses. In this paper, we find the informative frequency band (including the center frequency and bandwidth) of bearing fault induced repetitive impulses using the spectral negentropy based infogram. In Fourier spectrum, we identify planet bearing faults according to sideband characteristics around the center frequency. For demodulation analysis, we filter out the sensitive component based on the informative frequency band revealed by the infogram. In amplitude demodulated spectrum (squared envelope spectrum) of the sensitive component, we diagnose planet bearing faults by matching the present peaks with the theoretical fault characteristic frequencies. We further decompose the sensitive component into mono-component intrinsic mode functions (IMFs) to estimate their instantaneous frequencies, and select a sensitive IMF with an instantaneous frequency fluctuating around the center frequency for frequency demodulation analysis. In the frequency demodulated spectrum (Fourier spectrum of instantaneous frequency) of selected IMF, we discern planet bearing fault reasons according to the present peaks. The proposed spectral negentropy infogram based spectrum and demodulation analysis method is illustrated via a numerical simulated signal analysis. Considering the unique load bearing feature of planet bearings, experimental validations under both no-load and loading conditions are done to verify the derived fault symptoms and the proposed method. The localized faults on outer race, rolling element and inner race are successfully diagnosed.

Halotolerant plant-growth promoting rhizobacteria modulate gene expression and osmolyte production to improve salinity tolerance and growth in Capsicum annum L.

PubMed

Yasin, Nasim Ahmad; Akram, Waheed; Khan, Waheed Ullah; Ahmad, Sajid Rashid; Ahmad, Aqeel; Ali, Aamir

2018-06-04

Some rhizobacteria have demonstrated a noteworthy role in regulation of plant growth and biomass production under biotic and abiotic stresses. The present study was intended to explicate the ameliorative consequences of halotolerant plant growth-promoting rhizobacteria (HPGPR) on growth of capsicum plants subjected to salt stress. Salt stress was ascertained by supplementing 1 and 2 g NaCl kg -1 soil. The HPGPR positively invigorated growth attributes, chlorophyll, protein contents, and water use efficiency (WUE) of supplemented capsicum plants under salinity stress conditions. Bacillus fortis strain SSB21 caused highest significant increase in shoot length, root length, and fresh and dry biomass production of capsicum plants grown under saline conditions. This multi-trait bacterium also increased biosynthesis of proline and up-regulated the expression profiles of stress related genes including CAPIP2, CaKR1, CaOSM1, and CAChi2. On the other hand, B. fortis strain SSB21 inoculated plants exhibited reduced level of ethylene, lipid peroxidation, and reactive oxygen species (ROS). All these together contribute to activate physiological and biochemical processes involved in the mitigation of the salinity induced stress in capsicum plants.

The Sidebands of the Equatorial Electrojet: General Characteristic of the Westward Currents, as Deduced From CHAMP

NASA Astrophysics Data System (ADS)

Zhou, Yun-Liang; Lühr, Hermann; Alken, Patrick

2018-02-01

Based on 5 years (2001-2005) of magnetic field measurements made by the CHAMP satellite, latitudinal profiles of the equatorial electrojet (EEJ) have been derived. This study provides a comprehensive characterization of the reverse current EEJ sidebands. These westward currents peak at ±5° quasi-dipole latitude with typical amplitudes of 35% of the main EEJ. The diurnal amplitude variation is quite comparable with that of the EEJ. Similarly to the EEJ, the intensity is increasing with solar EUV flux, but with a steeper slope, indicating that not only the conductivity plays a role. For the longitude distribution we find, in general, larger amplitudes in the Western than in the Eastern Hemisphere. It is presently a common understanding that the reverse current EEJ sidebands are generated by eastward zonal winds at altitudes above about 120 km. In particular, a positive vertical gradient of wind speed generates westward currents at magnetic latitudes outside of 2° dip latitude. Interesting information about these features can be deduced from the sidebands' tidal characteristics. The longitudinal variation of the amplitude is dominated by a wave-1 pattern, which can primarily be attributed to the tidal components SPW1 and SW3. In case of the hemispheric amplitude differences these same two wave-1 components dominate. The ratio between sideband amplitude and main EEJ is largely controlled by the tidal features of the EEJ. The longitudinal patterns of the latitude, where the sidebands peak, resemble to some extent those of the amplitude. Current densities become larger when the peaks move closer to the magnetic equator.

Topological charge algebra of optical vortices in nonlinear interactions.

PubMed

Zhdanova, Alexandra A; Shutova, Mariia; Bahari, Aysan; Zhi, Miaochan; Sokolov, Alexei V

2015-12-28

We investigate the transfer of orbital angular momentum among multiple beams involved in a coherent Raman interaction. We use a liquid crystal light modulator to shape pump and Stokes beams into optical vortices with various integer values of topological charge, and cross them in a Raman-active crystal to produce multiple Stokes and anti-Stokes sidebands. We measure the resultant vortex charges using a tilted-lens technique. We verify that in every case the generated beams' topological charges obey a simple relationship, resulting from angular momentum conservation for created and annihilated photons, or equivalently, from phase-matching considerations for multiple interacting beams.

Biopolymers: Protein and Nucleic Acids

DTIC Science & Technology

1987-09-15

characterized a 45 kDa "ZSB, de!•ignted S’SB1, most extensively. SSB1 was isolated on the basis of preferential binding to sin ie-stranded versus double...stranded DNA and was subsequently shown also to bind to RNA (9). Although SSB1 seems to bind without sequen-e specificity, it is interesting to note...that it copurifies through several a inity steps with the yeast poly (A) binding protein (11, Sach3 and Jong, unpublished observations). SSB1 stimulates

Controlled cohort evaluation of the LiveLighter mass media campaign’s impact on adults’ reported consumption of sugar-sweetened beverages

PubMed Central

Morley, Belinda C; Niven, Philippa H; Dixon, Helen G; Swanson, Maurice G; McAleese, Alison B; Wakefield, Melanie A

2018-01-01

Objective To evaluate the LiveLighter ‘Sugary Drinks’ campaign impact on awareness, knowledge and sugar-sweetened beverage (SSB) consumption. Design Cohort study with population surveys undertaken in intervention and comparison states at baseline (n=900 each), with 78% retention at follow-up (intervention: n=673; comparison: n=730). Analyses tested interactions by state (intervention, comparison) and time (baseline, follow-up). Setting and participants Adults aged 25–49 years residing in the Australian states of Victoria and South Australia. Intervention The 6-week mass media campaign ran in Victoria in October/November 2015. It focused on the contribution of SSBs to the development of visceral ‘toxic fat’, graphically depicted around vital organs, and ultimately serious disease. Paid television advertising was complemented by radio, cinema, online and social media advertising, and stakeholder and community engagement. Primary outcome measure Self-reported consumption of SSBs, artificially sweetened drinks and water. Secondary outcome measures Campaign recall and recognition; knowledge of the health effects of overweight and SSB consumption; perceived impact of SSB consumption on body weight and of reduced consumption on health. Results A significant reduction in frequent SSB consumption was observed in the intervention state (intervention: 31% compared with 22%, comparison: 30% compared with 29%; interaction p<0.01). This was accompanied by evidence of increased water consumption (intervention: 66% compared with 73%; comparison: 68% compared with 67%; interaction p=0.09) among overweight/obese SSB consumers. This group also showed increased knowledge of the health effects of SSB consumption (intervention: 60% compared with 71%, comparison: 63% compared with 59%; interaction p<0.05) and some evidence of increased prevalence of self-referent thoughts about SSB’s relationship to weight gain (intervention: 39% compared with 45%, comparison: 43% compared with 38%; interaction p=0.06). Conclusions The findings provide evidence of reduced SSB consumption among adults in the target age range following the LiveLighter campaign. This is notable in a context where public health campaigns occur against a backdrop of heavy commercial product advertising promoting increased SSB consumption. PMID:29695387

Estimated Global, Regional, and National Disease Burdens Related to Sugar-Sweetened Beverage Consumption in 2010.

PubMed

Singh, Gitanjali M; Micha, Renata; Khatibzadeh, Shahab; Lim, Stephen; Ezzati, Majid; Mozaffarian, Dariush

2015-08-25

Sugar-sweetened beverages (SSBs) are consumed globally and contribute to adiposity. However, the worldwide impact of SSBs on burdens of adiposity-related cardiovascular diseases (CVDs), cancers, and diabetes mellitus has not been assessed by nation, age, and sex. We modeled global, regional, and national burdens of disease associated with SSB consumption by age/sex in 2010. Data on SSB consumption levels were pooled from national dietary surveys worldwide. The effects of SSB intake on body mass index and diabetes mellitus, and of elevated body mass index on CVD, diabetes mellitus, and cancers were derived from large prospective cohort pooling studies. Disease-specific mortality/morbidity data were obtained from Global Burden of Diseases, Injuries, and Risk Factors 2010 Study. We computed cause-specific population-attributable fractions for SSB consumption, which were multiplied by cause-specific mortality/morbidity to compute estimates of SSB-attributable death/disability. Analyses were done by country/age/sex; uncertainties of all input data were propagated into final estimates. Worldwide, the model estimated 184 000 (95% uncertainty interval, 161 000-208 000) deaths/y attributable to SSB consumption: 133 000 (126 000-139 000) from diabetes mellitus, 45 000 (26 000-61 000) from CVD, and 6450 (4300-8600) from cancers. Five percent of SSB-related deaths occurred in low-income, 70.9% in middle-income, and 24.1% in high-income countries. Proportional mortality attributable to SSBs ranged from <1% in Japanese >65 years if age to 30% in Mexicans <45 years of age. Among the 20 most populous countries, Mexico had largest absolute (405 deaths/million adults) and proportional (12.1%) deaths from SSBs. A total of 8.5 (2.8, 19.2) million disability-adjusted life years were related to SSB intake (4.5% of diabetes mellitus-related disability-adjusted life years). SSBs are a single, modifiable component of diet that can impact preventable death/disability in adults in high-, middle-, and low-income countries, indicating an urgent need for strong global prevention programs. © 2015 American Heart Association, Inc.

Mothers' child-feeding practices are associated with children's sugar-sweetened beverage intake.

PubMed

Park, Sohyun; Li, Ruowei; Birch, Leann

2015-04-01

Sugar-sweetened beverage (SSB) intake is a substantial source of energy in the diet of US children. We examined the associations between mothers' child-feeding practices and SSB intake among 6-y-old children. We analyzed data from the Year 6 Follow-up of the Infant Feeding Practices Study II in 1350 US children aged 6 y. The outcome variable was child's SSB intake. The exposure variables were 4 child-feeding practices of mothers: setting limits on sweets or junk foods, regulating their child's favorite food intake to prevent overconsumption, pressuring their child to eat enough, and pressuring their child to "clean the plate." We used multinomial logistic regression and controlled for child and maternal characteristics. Analyses were stratified on child weight status. The consumption of SSBs ≥1 time/d was observed among 17.1% of underweight/normal-weight children and in 23.2% of overweight/obese children. Adjusted ORs (aORs) of consuming SSBs ≥1 time/d (vs. no SSB consumption) were significantly lower in children whose mothers reported setting limits on sweets/junk foods (aOR: 0.29; 95% CI: 0.15, 0.58 for underweight/normal-weight children; aOR: 0.16; 95% CI: 0.03, 0.79 for overweight/obese children). SSB intake was higher among underweight/normal-weight children whose mothers reported trying to keep the child from eating too much of their favorite foods (aOR: 2.03; 95% CI: 1.25, 3.29). Mothers' tendency to pressure their children to consume more food or to "clean the plate" was not associated with child's SSB intake. SSBs were commonly consumed by young children. The odds of daily SSB intake were lower among children whose mothers set limits on sweets/junk foods regardless of child's weight but were higher among underweight/normal-weight children whose mothers restricted the child's favorite food intake. Future studies can investigate the impact of alternatives to restrictive feeding practices that could reduce children's SSB intake. © 2015 American Society for Nutrition.

Non-Markovian optimal sideband cooling

NASA Astrophysics Data System (ADS)

Triana, Johan F.; Pachon, Leonardo A.

2018-04-01

Optimal control theory is applied to sideband cooling of nano-mechanical resonators. The formulation described here makes use of exact results derived by means of the path-integral approach of quantum dynamics, so that no approximation is invoked. It is demonstrated that the intricate interplay between time-dependent fields and structured thermal bath may lead to improve results of the sideband cooling by an order of magnitude. Cooling is quantified by means of the mean number of phonons of the mechanical modes as well as by the von Neumann entropy. Potencial extension to non-linear systems, by means of semiclassical methods, is briefly discussed.

Method and means for generation of tunable laser sidebands in the far-infrared region

NASA Technical Reports Server (NTRS)

Pickett, Herbert M. (Inventor); Farhoomand, Jam (Inventor)

1987-01-01

A method for generating tunable far-infrared radiation is described. The apparatus includes a Schottky-barrier diode which has one side coupled through a conductor to a waveguide that carries a tunable microwave frequency; the diode has an opposite side which is coupled through a radiating whisker to a bias source. Infrared light is directed at the diode, and infrared light with tunable sidebands is radiated by the whisker through an open space to a reflector. The original infrared is separated from a tunable infrared sideband by a polarizing Michelson interferometer.

Nanosecond-pulse-controlled higher-order sideband comb in a GaAs optomechanical disk resonator in the non-perturbative regime

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

Xiong, Hao, E-mail: haoxiong1217@gmail.com; Si, Liu-Gang, E-mail: siliugang@gmail.com; Lü, Xin-You

2014-10-15

We propose an interesting scheme for tunable high-order sideband comb generation by utilizing ultrastrong optomechanical interaction in a GaAs optomechanical disk resonator beyond the perturbative approximation. We analyze the nonlinear nature of the optomechanical interaction, and give a full description of the non-perturbative effects. It is shown, within the non-perturbative regime, that high-order sideband comb with large intensities can be realized and controlled in a GaAs optomechanical disk resonator with experimentally achievable system parameters, and the non-perturbative regime leads to rich and nontrivial behavior.

Understanding photon sideband statistics and correlation for determining phonon coherence

NASA Astrophysics Data System (ADS)

Ding, Ding; Yin, Xiaobo; Li, Baowen

2018-01-01

Generating and detecting coherent high-frequency heat-carrying phonons have been topics of great interest in recent years. Although there have been successful attempts in generating and observing coherent phonons, rigorous techniques to characterize and detect phonon coherence in a crystalline material have been lagging compared to what has been achieved for photons. One main challenge is a lack of detailed understanding of how detection signals for phonons can be related to coherence. The quantum theory of photoelectric detection has greatly advanced the ability to characterize photon coherence in the past century, and a similar theory for phonon detection is necessary. Here, we reexamine the optical sideband fluorescence technique that has been used to detect high-frequency phonons in materials with optically active defects. We propose a quantum theory of phonon detection using the sideband technique and found that there are distinct differences in sideband counting statistics between thermal and coherent phonons. We further propose a second-order correlation function unique to sideband signals that allows for a rigorous distinction between thermal and coherent phonons. Our theory is relevant to a correlation measurement with nontrivial response functions at the quantum level and can potentially bridge the gap of experimentally determining phonon coherence to be on par with that of photons.

Urban versus suburban perceptions of the neighborhood food environment as correlates of adolescent food purchasing

PubMed Central

Hearst, Mary O.; Pasch, Keryn E.; Laska, Melissa N.

2012-01-01

Objective To assess the relationship between adolescent perception of time to walk to neighborhood food retail outlets and purchasing of sugar sweetened beverages (SSB), fast and convenience food items and test for differences by urban versus suburban environment. Design Cross-sectional observational study. Setting Twin Cities Metropolitan Area, Minnesota. Subjects Adolescents from two studies completed survey-based measures on perceptions of time to walk to food retail outlets from home, purchasing patterns of SSB and fast and convenience store items, perceptions of personal safety and pedestrian infrastructure and demographic characteristics. Descriptive analysis, Spearman correlations and multivariate linear regression, accounting for clustering, were conducted using SAS. Results There were 634 adolescents, approximately half male, predominately white, with a middle-class background. Greater perceived time to food outlets were associated with less frequent purchasing of SSB, convenience store foods and fast food items. Multivariate models showed that a perceived shorter walking time (i.e. 1–5 versus 31+ minutes) was significantly associated with more SSB purchasing. SSB purchases were also significantly associated with the number of food outlets within a 10–minute walk (B=0.05, p=0.02). Conclusions A reduction in consumption of SSB and other energy dense snacks is an important obesity prevention approach. An approach offering alternatives or reducing exposure in addition to education to alter purchasing habits may contribute to improving dietary habits and reducing the obesity epidemic. PMID:21859510

The effect of sugar-sweetened beverage front-of-pack labels on drink selection, health knowledge and awareness: An online randomised controlled trial.

PubMed

Billich, Natassja; Blake, Miranda R; Backholer, Kathryn; Cobcroft, Megan; Li, Vincy; Peeters, Anna

2018-06-04

Sugar-sweetened beverages (SSBs) provide little nutritional value and are associated with an increased risk of diet-related diseases. Despite this, SSB consumption is high globally. One emerging strategy aimed at reducing SSB consumption involves the use of front-of-pack (FOP) labels that clearly identify the risks associated with SSB consumption. The aim of this research study was to determine whether FOP labels with a graphic warning, text warning, sugar information (with the number of teaspoons of added sugar) or Health Star Rating (HSR) reduces intended choice of a SSB in an online choice experiment with young Australian adults. 994 participants were recruited and completed the online choice experiment. Compared to the control group who were not exposed to a label, the graphic warning, text warning, sugar information and HSR labels all significantly reduced selection of a SSB in the choice scenario. The magnitude of effect was greatest for the graphic warning label (OR 0.22 95% CI 0.14-0.35). Compared to the control group, only the HSR label significantly increased selections of the high HSR drinks (OR 2.18 95% CI 1.20-3.97). FOP labels, particularly those with graphic warnings, have the potential to reduce intended SSB purchases. Labels that also identify healthier alternatives may influence consumers to substitute SSBs with healthier drinks. Copyright © 2018. Published by Elsevier Ltd.

Contrasting effects of ethylene biosynthesis on induced plant resistance against a chewing and a piercing-sucking herbivore in rice.

PubMed

Lu, Jing; Li, Jiancai; Ju, Hongping; Liu, Xiaoli; Erb, Matthias; Wang, Xia; Lou, Yonggen

2014-11-01

Ethylene is a stress hormone with contrasting effects on herbivore resistance. However, it remains unknown whether these differences are plant- or herbivore-specific. We cloned a rice 1-aminocyclopropane-1-carboxylic acid (ACC) synthase gene, OsACS2, whose transcripts were rapidly up-regulated in response to mechanical wounding and infestation by two important pests: the striped stem borer (SSB) Chilo suppressalis and the brown planthopper (BPH) Nilaparvata lugens. Antisense expression of OsACS2 (as-acs) reduced elicited ethylene emission, SSB-elicited trypsin protease inhibitor (TrypPI) activity, SSB-induced volatile release, and SSB resistance. Exogenous application of ACC restored TrypPI activity and SSB resistance. In contrast to SSB, BPH infestation increased volatile emission in as-acs lines. Accordingly, BPH preferred to feed and oviposit on wild-type (WT) plants--an effect that could be attributed to two repellent volatiles, 2-heptanone and 2-heptanol, that were emitted in higher amounts by as-acs plants. BPH honeydew excretion was reduced and natural enemy attraction was enhanced in as-acs lines, resulting in higher overall resistance to BPH. These results demonstrate that ethylene signaling has contrasting, herbivore-specific effects on rice defense responses and resistance against a chewing and a piercing-sucking insect, and may mediate resistance trade-offs between herbivores of different feeding guilds in rice. © The Author 2014. Published by the Molecular Plant Shanghai Editorial Office in association with Oxford University Press on behalf of CSPB and IPPE, SIBS, CAS.

Design of an MSAT-X mobile transceiver and related base and gateway stations

NASA Technical Reports Server (NTRS)

Fang, Russell J. F.; Bhaskar, Udaya; Hemmati, Farhad; Mackenthun, Kenneth M.; Shenoy, Ajit

1987-01-01

This paper summarizes the results of a design study of the mobile transceiver, base station, and gateway station for NASA's proposed Mobile Satellite Experiment (MSAT-X). Major ground segment system design issues such as frequency stability control, modulation method, linear predictive coding vocoder algorithm, and error control technique are addressed. The modular and flexible transceiver design is described in detail, including the core, RF/IF, modem, vocoder, forward error correction codec, amplitude-companded single sideband, and input/output modules, as well as the flexible interface. Designs for a three-carrier base station and a 10-carrier gateway station are also discussed, including the interface with the controllers and with the public-switched telephone networks at the gateway station. Functional specifications are given for the transceiver, the base station, and the gateway station.

Electro-optical co-simulation for integrated CMOS photonic circuits with VerilogA.

PubMed

Sorace-Agaskar, Cheryl; Leu, Jonathan; Watts, Michael R; Stojanovic, Vladimir

2015-10-19

We present a Cadence toolkit library written in VerilogA for simulation of electro-optical systems. We have identified and described a set of fundamental photonic components at the physical level such that characteristics of composite devices (e.g. ring modulators) are created organically - by simple instantiation of fundamental primitives. Both the amplitude and phase of optical signals as well as optical-electrical interactions are simulated. We show that the results match other simulations and analytic solutions that have previously been compared to theory for both simple devices, such as ring resonators, and more complicated devices and systems such as single-sideband modulators, WDM links and Pound Drever Hall Locking loops. We also illustrate the capability of such toolkit for co-simulation with electronic circuits, which is a key enabler of the electro-optic system development and verification.

Design of an MSAT-X mobile transceiver and related base and gateway stations

NASA Astrophysics Data System (ADS)

Fang, Russell J. F.; Bhaskar, Udaya; Hemmati, Farhad; Mackenthun, Kenneth M.; Shenoy, Ajit

This paper summarizes the results of a design study of the mobile transceiver, base station, and gateway station for NASA's proposed Mobile Satellite Experiment (MSAT-X). Major ground segment system design issues such as frequency stability control, modulation method, linear predictive coding vocoder algorithm, and error control technique are addressed. The modular and flexible transceiver design is described in detail, including the core, RF/IF, modem, vocoder, forward error correction codec, amplitude-companded single sideband, and input/output modules, as well as the flexible interface. Designs for a three-carrier base station and a 10-carrier gateway station are also discussed, including the interface with the controllers and with the public-switched telephone networks at the gateway station. Functional specifications are given for the transceiver, the base station, and the gateway station.

Sideband pump-probe technique resolves nonlinear modulation response of PbS/CdS quantum dots on a silicon nitride waveguide

NASA Astrophysics Data System (ADS)

Kolarczik, Mirco; Ulbrich, Christian; Geiregat, Pieter; Zhu, Yunpeng; Sagar, Laxmi Kishore; Singh, Akshay; Herzog, Bastian; Achtstein, Alexander W.; Li, Xiaoqin; van Thourhout, Dries; Hens, Zeger; Owschimikow, Nina; Woggon, Ulrike

2018-01-01

For possible applications of colloidal nanocrystals in optoelectronics and nanophotonics, it is of high interest to study their response at low excitation intensity with high repetition rates, as switching energies in the pJ/bit to sub-pJ/bit range are targeted. We develop a sensitive pump-probe method to study the carrier dynamics in colloidal PbS/CdS quantum dots deposited on a silicon nitride waveguide after excitation by laser pulses with an average energy of few pJ/pulse. We combine an amplitude modulation of the pump pulse with phase-sensitive heterodyne detection. This approach permits to use co-linearly propagating co-polarized pulses. The method allows resolving transmission changes of the order of 10-5 and phase changes of arcseconds. We find a modulation on a sub-nanosecond time scale caused by Auger processes and biexciton decay in the quantum dots. With ground state lifetimes exceeding 1 μs, these processes become important for possible realizations of opto-electronic switching and modulation based on colloidal quantum dots emitting in the telecommunication wavelength regime.

Nativity is associated with sugar-sweetened beverage and fast-food meal consumption among Mexican-origin women in Texas border colonias.

PubMed

Sharkey, Joseph R; Johnson, Cassandra M; Dean, Wesley R

2011-09-30

Trends of increasing obesity are especially pronounced among Mexican-origin women. There is little understanding of dietary patterns among U.S.- and Mexico-born Mexican-origin individuals residing in new-destination immigrant communities in the United States, especially behaviors related to obesity, such as consumption of sugar-sweetened beverages (SSB) and fast-food meals (FFM). The study used survey data of 599 adult Mexican-origin women from the 610 women who completed the 2009 Colonia Household and Community Food Resource Assessment (C-HCFRA), which was completed in person by trained promotora-researchers in 44 colonias near the Texas border towns of Progreso and La Feria. Data included demographic characteristics (age, education, nativity or country of birth, household income, household composition, and employment status), access to transportation, self-reported height and weight, food and nutrition assistance program participation, and consumption of SSB and FFM. Descriptive statistics were calculated by nativity (U.S.-born vs. Mexico-born); multivariable linear regression models were estimated for correlates of consumption of SSB and FFM. There are three major findings related to nativity. First, U.S.-born women consumed more SSB and FFM than Mexican-born counterparts in the same areas of colonias. Second, in the combined sample and controlling for other population characteristics, being born in Mexico was independently associated with FFM (fewer FFM), but not with SSB. Third, in analyses stratified by nativity, FFM and SSB were associated with each other among both nativity groups. Among Mexico-born women only, age, presence of a child, or being a lone parent was significantly associated with SSB; full-time employment, being a lone parent, and SSB consumption were each independently associated with increased frequency of FFM. Our analyses revealed differences in prevalence and correlates of SSB and FFM based on country of birth. Nativity, as a proxy for acculturation, may indicate the extent that immigrants have adopted behaviors from their new environment. However, nativity could also indicate limited accessibility to resources such as food/nutrition assistance programs, transportation, and proper documentation. Additionally, future research should focus on expanding our understanding of the meaning of nativity among individuals who share common contextual factors, but may have different life course experiences and resources needed to transition into a new place. Additional measures should be considered such as educational and occupational background, migration history, documentation status, and dietary acculturation, which may better explain heterogeneity within Hispanic subgroups.

Injection locking method for Raman beams in atom interferometer

NASA Astrophysics Data System (ADS)

Zi, Fei; Deng, Jianing; Zeng, Daji; Li, Tong; Sun, Mingli; Zhang, Xian; Huang, Kaikai; Lu, Xuanhui

2018-03-01

We present a novel method to generate two phase-locked beams with a frequency offset of 6.834 GHz. The output of the master laser is firstly modulated by an electric optical modulator (EOM), and then further injected into an Extended Cavity Diode Lasers (ECDL) which is used to filter out the unwanted mode and amplify the laser power. By locking to the first-order lower sideband of the modulated master laser, the average variance of the phase fluctuations is 5.6 x 10-3 rad2 , which implies phase coherence of 99.44% between the master laser and the slave ECDL. The line width of the beat notes is less than 1Hz. For the long term stability, with the delicate design of the electronic controller in ECDL, the phase coherence of the two laser beams can be stabilized over 200 hours without any adjustment. The Raman system is applicable for gravity detection with a preliminary sensitivity Δg/g of 4.5 x 10-7 for interrogation time of 1500 s.

A photonic circuit for complementary frequency shifting, in-phase quadrature/single sideband modulation and frequency multiplication: analysis and integration feasibility

NASA Astrophysics Data System (ADS)

Hasan, Mehedi; Hu, Jianqi; Nikkhah, Hamdam; Hall, Trevor

2017-08-01

A novel photonic integrated circuit architecture for implementing orthogonal frequency division multiplexing by means of photonic generation of phase-correlated sub-carriers is proposed. The circuit can also be used for implementing complex modulation, frequency up-conversion of the electrical signal to the optical domain and frequency multiplication. The principles of operation of the circuit are expounded using transmission matrices and the predictions of the analysis are verified by computer simulation using an industry-standard software tool. Non-ideal scenarios that may affect the correct function of the circuit are taken into consideration and quantified. The discussion of integration feasibility is illustrated by a photonic integrated circuit that has been fabricated using 'library' components and which features most of the elements of the proposed circuit architecture. The circuit is found to be practical and may be fabricated in any material platform that offers a linear electro-optic modulator such as organic or ferroelectric thin films hybridized with silicon photonics.

Strategic Messaging to Promote Taxation of Sugar-Sweetened Beverages: Lessons From Recent Political Campaigns

PubMed Central

Jou, Judy; Niederdeppe, Jeff; Barry, Colleen L.; Gollust, Sarah E.

2014-01-01

Objectives. This study explored the use of strategic messaging by proponents of sugar-sweetened beverage (SSB) taxation to influence public opinion and shape the policy process, emphasizing the experiences in El Monte and Richmond, California, with SSB tax proposals in 2012. Methods. We conducted 18 semistructured interviews with key stakeholders about the use and perceived effectiveness of messages supporting and opposing SSB taxation, knowledge sharing among advocates, message dissemination, and lessons learned from their messaging experiences. Results. The protax messages most frequently mentioned by respondents were reinvesting tax revenue into health-related programs and linking SSB consumption to health outcomes such as obesity and diabetes. The most frequently mentioned antitax messages addressed negative economic effects on businesses and government restriction of personal choice. Factors contributing to perceived messaging success included clearly defining “sugar-sweetened beverage” and earmarking funds for obesity prevention, incorporating cultural sensitivity into messaging, and providing education about the health effects of SSB consumption. Conclusions. Sugar-sweetened beverage taxation has faced significant challenges in gaining political and public support. Future campaigns can benefit from insights gained through the experiences of stakeholders involved in previous policy debates. PMID:24625177

Gender Differences in the relationship between carbonated sugar-sweetened beverage intake and the likelihood of hypertension according to obesity.

PubMed

Song, Hong Ji; Paek, Yu Jin; Choi, Min Kyu; Yoo, Ki-Bong; Kang, Jae-Heon; Lee, Hae-Jeung

2017-06-01

The aim of the present study was to investigate the association between hypertension and carbonated sugar-sweetened beverages (SSB) intake according to gender and obesity. The study used data from 2007, 2008 and 2009 Korea National Health and Nutrition Examination Surveys. A total of 9869 subjects (men = 3845 and women = 6024) were included. SSB intakes were calculated from food frequency questionnaires. Odds ratios (ORs) and 95 % confidence interval (CI) for hypertension were assessed using survey logistic regression and multivariable adjusted models. A total of 14.5 % of individuals were classified as having hypertension. The likelihood of hypertension in the third, fourth and fifth quintiles for SSB intake increased to OR 1.00, 1.20 and 1.42 respectively, after adjusting for confounding factors. Compared to the participants in the lowest tertile for SSB intake, participants in the third tertile showed an increased likelihood of hypertension with ORs (CI) of 2.00 (1.21-3.31) and 1.75 (1.23-2.49) for obese women and non-obese men, respectively. The present study showed gender differences in the relationship between carbonated SSB intake and the hypertension according to obesity.

In Situ Detection of Strong Langmuir Turbulence Processes in Solar Type III Radio Bursts

NASA Technical Reports Server (NTRS)

Golla, Thejappa; Macdowall, Robert J.; Bergamo, M.

2012-01-01

The high time resolution observations obtained by the WAVES experiment of the STEREO spacecraft in solar type III radio bursts show that Langmuir waves often occur as intense localized wave packets. These wave packets are characterized by short durations of only a few ms and peak intensities, which well exceed the supersonic modulational instability (MI) thresholds. These timescales and peak intensities satisfy the criterion of the solitons collapsed to spatial scales of a few hundred Debye lengths. The spectra of these wave packets consist of primary spectral peaks corresponding to beam-resonant Langmuir waves, two or more sidebands corresponding to down-shifted and up-shifted daughter Langmuir waves, and low frequency enhancements below a few hundred Hz corresponding to daughter ion sound waves. The frequencies and wave numbers of these spectral components satisfy the resonance conditions of the modulational instability (MI). Moreover, the tricoherences, computed using trispectral analysis techniques show that these spectral components are coupled to each other with a high degree of coherency as expected of the MI type of four wave interactions. The high intensities, short scale lengths, sideband spectral structures and low frequency spectral enhancements and, high levels of tricoherences amongst the spectral components of these wave packets provide unambiguous evidence for the supersonic MI and related strong turbulence processes in type III radio bursts. The implication of these observations include: (1) the MI and related strong turbulence processes often occur in type III source regions, (2) the strong turbulence processes probably play very important roles in beam stabilization as well as conversion of Langmuir waves into escaping radiation at the fundamental and second harmonic of the electron plasma frequency, fpe, and (3) the Langmuir collapse probably follows the route of MI in type III radio bursts.

Low power generation of equalized broadband CW supercontinua using a novel technique incorporating modulation instability of line broadened pump

NASA Astrophysics Data System (ADS)

Prakash, Roopa; Choudhury, Vishal; Arun, S.; Supradeepa, V. R.

2018-02-01

Continuous-wave(CW) supercontinuum sources find applications in various domains such as imaging, spectroscopy, test and measurement. They are generated by pumping an optical fiber with a CW laser in the anomalous-dispersion region close to its zero-dispersion wavelength. Modulation instability(MI) sidebands are created, and further broadened and equalized by additional nonlinear processes generating the supercontinuum. This necessitates high optical powers and at lower powers, only MI sidebands can be seen without the formation of the supercontinuum. Obtaining a supercontinuum at low, easily manageable optical powers is attractive for many applications, but current techniques cannot achieve this. In this work, we propose a new mechanism for low power supercontinuum generation utilizing the modified MI gain spectrum for a line-broadened, decorrelated pump. A novel two-stage generation mechanism is demonstrated, where the first stage constituting standard telecom fiber slightly broadens the input pump linewidth. However, this process in the presence of dispersion, acts to de-correlate the different spectral components of the pump signal. When this is sent through highly nonlinear fiber near its zero-dispersion wavelength, the shape of the MI gain spectrum is modified, and this process naturally results in the generation of a broadband, equalized supercontinuum source at much lower powers than possible using conventional single stage spectral broadening. Here, we demonstrate a 0.5W supercontinuum source pumped using a 4W Erbium-Ytterbium co-doped fiber laser with a bandwidth spanning from 1300nm to 2000nm. We also demonstrate an interesting behaviour of this technique of relative insensitivity to the pump wavelength vis-a-vis zero-dispersion wavelength of the fiber.

Few-Nucleon Charge Radii and a Precision Isotope Shift Measurement in Helium

NASA Astrophysics Data System (ADS)

Hassan Rezaeian, Nima; Shiner, David

2015-05-01

Precision atomic theory and experiment provide a valuable method to determine few nucleon charge radii, complementing the more direct scattering approaches, and providing sensitive tests of few-body nuclear theory. Some puzzles with respect to this method exist, particularly in the muonic and electronic measurements of the proton radius, and as well with respect to measurements of nuclear size in helium. We perform precision measurements of the isotope shift of the 23S -23P transitions in 3He and 4He. A tunable laser frequency discriminator and electro-optic modulation technique give precise frequency and intensity control. We select (ts <50 ms) and stabilize the intensity of the required sideband and eliminate the unused sidebands (<= 10¬5) . The technique uses a MEMS fiber switch (ts = 10 ms) and several temperature stabilized narrow band (3 GHz) fiber gratings. A fiber based optical circulator and amplifier provide the desired isolation and net gain for the selected frequency. A beam with both species of helium is achieved using a custom fiber laser for simultaneous optical pumping. A servo-controlled retro-reflected laser beam eliminates Doppler effects. Careful detection design and software control allows for unbiased data collection. Current results will be discussed. This work is supported by NSF PHY-1068868 and PHY-1404498.

Mixed methods evaluation of a randomized control pilot trial targeting sugar-sweetened beverage behaviors.

PubMed

Zoellner, Jamie; Cook, Emily; Chen, Yvonnes; You, Wen; Davy, Brenda; Estabrooks, Paul

2013-02-01

This Excessive sugar-sweetened beverage (SSB) consumption and low health literacy skills have emerged as two public health concerns in the United States (US); however, there is limited research on how to effectively address these issues among adults. As guided by health literacy concepts and the Theory of Planned Behavior (TPB), this randomized controlled pilot trial applied the RE-AIM framework and a mixed methods approach to examine a sugar-sweetened beverage (SSB) intervention (SipSmartER), as compared to a matched-contact control intervention targeting physical activity (MoveMore). Both 5-week interventions included two interactive group sessions and three support telephone calls. Executing a patient-centered developmental process, the primary aim of this paper was to evaluate patient feedback on intervention content and structure. The secondary aim was to understand the potential reach (i.e., proportion enrolled, representativeness) and effectiveness (i.e. health behaviors, theorized mediating variables, quality of life) of SipSmartER. Twenty-five participants were randomized to SipSmartER (n=14) or MoveMore (n=11). Participants' intervention feedback was positive, ranging from 4.2-5.0 on a 5-point scale. Qualitative assessments reavealed several opportunties to improve clarity of learning materials, enhance instructions and communication, and refine research protocols. Although SSB consumption decreased more among the SipSmartER participants (-256.9 ± 622.6 kcals), there were no significant group differences when compared to control participants (-199.7 ± 404.6 kcals). Across both groups, there were significant improvements for SSB attitudes, SSB behavioral intentions, and two media literacy constructs. The value of using a patient-centered approach in the developmental phases of this intervention was apparent, and pilot findings suggest decreased SSB may be achieved through targeted health literacy and TPB strategies. Future efforts are needed to examine the potential public health impact of a large-scale trial to address health literacy and reduce SSB.

The potential link between sugar-sweetened beverage consumption and post-exercise airway narrowing across puberty: a longitudinal cohort study.

PubMed

Emerson, Sam R; Rosenkranz, Sara K; Rosenkranz, Richard R; Kurti, Stephanie P; Harms, Craig A

2016-09-01

The prevalence of asthma is rising, presenting serious public health challenges. Recent data suggest that sugar-sweetened beverage (SSB) consumption plays a role in asthma aetiology. The purpose of the present study was to determine whether SSB consumption is linked to post-exercise airway narrowing (predictor of asthma development) across puberty. Participants completed pulmonary function tests, physical activity and dietary habit questionnaires, and an exercise test to exhaustion. Community in Manhattan, Kansas, USA. We recruited ten boys and ten girls from an original cohort of forty participants tested in our laboratory approximately 5 years prior. Participants were aged 9·7 (sd 0·9) years at baseline and 14·7 (sd 0·9) years at follow-up. Pre-puberty, boys consumed 6·8 (sd 4·8) servings/week and girls consumed 6·9 (sd 3·7) servings/week, while post-puberty boys consumed 11·5 (sd 5·3) servings/week and girls consumed 7·7 (sd 4·3) servings/week. Using Pearson correlation, SSB consumption was not significantly related to post-exercise airway narrowing at pre-puberty (r=-0·35, P=0·130). In linear regression analyses, SSB consumption was significantly related to post-exercise airway narrowing post-puberty before (standardized β=-0·60, P=0·005) but not after (standardized β=-0·33, P=0·211) adjustment for confounders. Change in SSB consumption from pre- to post-puberty was significantly associated with post-exercise airway narrowing post-puberty (r=-0·61, P=0·010) and change in post-exercise airway narrowing from pre- to post-puberty (r=-0·45, P=0·048) when assessed via Pearson correlations. These findings suggest a possible link between SSB consumption and asthma development during maturation. Reduced SSB intake may be a possible public health avenue for blunting rising asthma prevalence.

Sugar-Sweetened Beverages and Obesity Risk in Children and Adolescents: A Systematic Analysis on How Methodological Quality May Influence Conclusions.

PubMed

Bucher Della Torre, Sophie; Keller, Amélie; Laure Depeyre, Jocelyne; Kruseman, Maaike

2016-04-01

In the context of a worldwide high prevalence of childhood obesity, the role of sugar-sweetened beverage (SSB) consumption as a cause of excess weight gain remains controversial. Conflicting results may be due to methodological issues in original studies and in reviews. The aim of this review was to systematically analyze the methodology of studies investigating the influence of SSB consumption on risk of obesity and obesity among children and adolescents, and the studies' ability to answer this research question. A systematic review of cohort and experimental studies published until December 2013 in peer-reviewed journals was performed on Medline, CINAHL, Web of Knowledge, and ClinicalTrials.gov. Studies investigating the influence of SSB consumption on risk of obesity and obesity among children and adolescents were included, and methodological quality to answer this question was assessed independently by two investigators using the Academy of Nutrition and Dietetics Quality Criteria Checklist. Among the 32 identified studies, nine had positive quality ratings and 23 studies had at least one major methodological issue. Main methodological issues included SSB definition and inadequate measurement of exposure. Studies with positive quality ratings found an association between SSB consumption and risk of obesity or obesity (n=5) (ie, when SSB consumption increased so did obesity) or mixed results (n=4). Studies with a neutral quality rating found a positive association (n=7), mixed results (n=9), or no association (n=7). The present review shows that the majority of studies with strong methodology indicated a positive association between SSB consumption and risk of obesity or obesity, especially among overweight children. In addition, study findings highlight the need for the careful and precise measurement of the consumption of SSBs and of important confounders. Copyright © 2016 Academy of Nutrition and Dietetics. Published by Elsevier Inc. All rights reserved.

Single-cell antibody nanowells: a novel technology in detecting anti-SSA/Ro60- and anti-SSB/La autoantibody-producing cells in peripheral blood of rheumatic disease patients.

PubMed

Esfandiary, Lida; Gupta, Nirupama; Voigt, Alexandria; Wanchoo, Arun; Chan, Edward K L; Sukumaran, Sukesh; Nguyen, Cuong Q

2016-05-17

Anti-SSA/Ro60 and anti-SSB/La are essential serological biomarkers for rheumatic diseases, specifically Sjögren's syndrome (SS) and systemic lupus erythematosus (SLE). Currently, laboratory detection technology and platforms are designed with an emphasis on high-throughput methodology; therefore, the relationship of sensitivity with specificity remains a significant area for improvement. In this study, we used single-cell antibody nanowells (SCAN) technology to directly profile individual B cells producing antibodies against specific autoantigens such as SSA/Ro60 and SSB/La. Peripheral blood mononuclear cells were isolated using Ficoll gradient. Fluorescently labeled cells were added to fabricated nanowells and imaged using a high-speed epifluorescence microscope. The microengraving process was conducted using printed slides coated with immunoglobulins. Printed slides were hybridized with fluorescence-conjugated immunoglobulin G (IgG), SSA/Ro60, and SSB/La antigens. Microarray spots were analyzed for nanowells with single live B cells that produced antigen-specific autoantibodies. Our results indicate that SCAN can simultaneously detect high frequencies of anti-SSA/Ro60 and anti-SSB/La with a specific IgG isotype in peripheral blood mononuclear cells of patients, as well as measure their individual secretion levels. The data showed that patients with SS and SLE exhibited higher frequency and greater concentration of anti-SSA/Ro60- and anti-SSB/La-producing B cells in the IgG isotype. Furthermore, individual B cells of patients produced higher levels of IgG-specific anti-SSA/Ro60 autoantibody, but not IgG-specific anti-SSB/La autoantibody, compared with healthy control subjects. These results support the application of SCAN as a robust multiparametric analytical bioassay that can directly measure secretion of autoantibody and accurately report antigen-specific, autoantibody-producing cells.

Sugar-sweetened beverage consumption and genetic predisposition to obesity in 2 Swedish cohorts.

PubMed

Brunkwall, Louise; Chen, Yan; Hindy, George; Rukh, Gull; Ericson, Ulrika; Barroso, Inês; Johansson, Ingegerd; Franks, Paul W; Orho-Melander, Marju; Renström, Frida

2016-09-01

The consumption of sugar-sweetened beverages (SSBs), which has increased substantially during the last decades, has been associated with obesity and weight gain. Common genetic susceptibility to obesity has been shown to modify the association between SSB intake and obesity risk in 3 prospective cohorts from the United States. We aimed to replicate these findings in 2 large Swedish cohorts. Data were available for 21,824 healthy participants from the Malmö Diet and Cancer study and 4902 healthy participants from the Gene-Lifestyle Interactions and Complex Traits Involved in Elevated Disease Risk Study. Self-reported SSB intake was categorized into 4 levels (seldom, low, medium, and high). Unweighted and weighted genetic risk scores (GRSs) were constructed based on 30 body mass index [(BMI) in kg/m(2)]-associated loci, and effect modification was assessed in linear regression equations by modeling the product and marginal effects of the GRS and SSB intake adjusted for age-, sex-, and cohort-specific covariates, with BMI as the outcome. In a secondary analysis, models were additionally adjusted for putative confounders (total energy intake, alcohol consumption, smoking status, and physical activity). In an inverse variance-weighted fixed-effects meta-analysis, each SSB intake category increment was associated with a 0.18 higher BMI (SE = 0.02; P = 1.7 × 10(-20); n = 26,726). In the fully adjusted model, a nominal significant interaction between SSB intake category and the unweighted GRS was observed (P-interaction = 0.03). Comparing the participants within the top and bottom quartiles of the GRS to each increment in SSB intake was associated with 0.24 (SE = 0.04; P = 2.9 × 10(-8); n = 6766) and 0.15 (SE = 0.04; P = 1.3 × 10(-4); n = 6835) higher BMIs, respectively. The interaction observed in the Swedish cohorts is similar in magnitude to the previous analysis in US cohorts and indicates that the relation of SSB intake and BMI is stronger in people genetically predisposed to obesity.

A tax on sugar sweetened beverages in Colombia: Estimating the impact on overweight and obesity prevalence across socio economic levels.

PubMed

Vecino-Ortiz, Andres I; Arroyo-Ariza, Daniel

2018-05-26

Colombia has a high prevalence of overweight (56%) and obesity (19%) among adults and is experiencing a growing trend in the prevalence of associated chronic conditions. Evidence suggests that sugar sweetened beverages (SSB) are associated to overweight/obesity, and that taxes on these beverages could reduce their associated health consequences. This paper assesses the potential effect of different levels of a SSB tax in Colombia on overweight and obesity prevalence. Using peer-reviewed local data on own-price elasticity of SSB, we applied a comparative risk assessment strategy to simulate the effect of the SSB tax on a nationally representative nutritional survey with 7140 adults in 2010 (ENSIN, 2010). Our results varied depending on the tax scenario, pass-through assumption and household socio economic strata (SES). We found that among individuals belonging to lower SES households, the SSB tax would reduce overweight and obesity between 1.5-4.9 and 1.1-2.4 percentage points (p < 0.05), respectively. Among individuals belonging to higher SES households, we found no statistically significant effects on obesity, and a reduction on overweight prevalence between 2.9 and 3.9 percentage points (p < 0.05). In the most conservative scenario (40% pass-through), a tax rate of at least 75 cents of Colombian peso (0.75 COP) per milliliter (24% of the average price) is needed to have statistically significant effects on both overweight and obesity prevalence among lower SES households. The results of this study suggest that a SSB tax could reduce the overweight and obesity prevalence in Colombia, especially among lower SES households. This study shows that SSB taxes have a particularly beneficial effect in the most vulnerable population. Additional social and individual benefits, or individual costs arising from the tax are not assessed in this research, implying that even larger health gains could be observed. Copyright © 2018 Elsevier Ltd. All rights reserved.

Sugar-Sweetened Beverage and Water Intake in Relation to Diet Quality in U.S. Children.

PubMed

Leung, Cindy W; DiMatteo, S Gemma; Gosliner, Wendi A; Ritchie, Lorrene D

2018-03-01

Sugar-sweetened beverages (SSBs) are a major contributor to children's added sugar consumption. This study examines whether children's SSB and water intakes are associated with diet quality and total energy intake. Using data on children aged 2-18 years from the 2009-2014 National Health and Nutrition Examination Survey, linear regression models were used to analyze SSB and water intake in relation to Healthy Eating Index 2010 (HEI-2010) scores and total energy intake. Generalized linear models were used to analyze SSB and water intake in relation to the HEI-2010 scores. Analyses were conducted including and excluding caloric contributions from SSBs and were conducted in 2016-2017. SSB intake was inversely associated with the HEI-2010 total scores (9.5-point lower score comparing more than two servings/day with zero servings/day, p-trend<0.0001) and positively associated with total energy intake (394 kcal higher comparing more than two servings/day with zero servings/day, p-trend<0.0001). The associations between SSB and HEI-2010 total scores were similar when SSBs were excluded from HEI-2010 calculations. Water intake was positively associated with HEI-2010 total scores, but not associated with total energy intake. SSB intake was inversely associated with several HEI-2010 component scores, notably vegetables, total fruit, whole fruit, greens and beans, whole grains, dairy, seafood and plant proteins, and empty calories. Water intake was positively associated with most of the same HEI-2010 component scores. Children who consume SSBs have poorer diet quality and higher total energy intake than children who do not consume SSBs. Interventions for obesity and chronic disease should focus on replacing SSBs with water and improving other aspects of diet quality that correlate with SSB consumption. Copyright © 2017 American Journal of Preventive Medicine. Published by Elsevier Inc. All rights reserved.

Report of Sugar-Sweetened Beverages Offered in Pennsylvania Childcare Centers.

PubMed

Lutzkanin, Kristen M; Myers, Abigail K; Schaefer, Eric W; Sekhar, Deepa L

2016-06-01

The study objective was to quantify sugar-sweetened beverage (SSB) offerings to children in Pennsylvania (PA) childcare centers and determine whether this information is communicated to parents. In October 2014, a SurveyMonkey link was sent to 4461 PA childcare centers. The 518 respondents represented 88% of PA counties. 279 centers (54%) serve SSBs. 330 (65%) of childcare centers provide parents a report of their child's daily intake. Of 185 centers serving SSBs and providing a daily intake report, 91% include SSB consumption. In total, 38% of centers (103/272) offer but do not report SSB consumption. In 96% of centers, parents may request their child not receive SSBs. In conclusion, though more than half of PA childcare centers surveyed offer SSBs, those providing daily intake reports usually include SSB consumption. Requiring daily intake reports may be a strategy to increase parental awareness of items consumed outside the home. © The Author(s) 2015.

Application of the SSB biosensor to study in vitro transcription.

PubMed

Cook, Alexander; Hari-Gupta, Yukti; Toseland, Christopher P

2018-02-12

Gene expression, catalysed by RNA polymerases (RNAP), is one of the most fundamental processes in living cells. The majority of methods to quantify mRNA are based upon purification of the nucleic acid which leads to experimental inaccuracies and loss of product, or use of high cost dyes and sensitive spectrophotometers. Here, we describe the use of a fluorescent biosensor based upon the single stranded binding (SSB) protein. In this study, the SSB biosensor showed similar binding properties to mRNA, to that of its native substrate, single-stranded DNA (ssDNA). We found the biosensor to be reproducible with no associated loss of product through purification, or the requirement for expensive dyes. Therefore, we propose that the SSB biosensor is a useful tool for comparative measurement of mRNA yield following in vitro transcription. Copyright © 2018 The Authors. Published by Elsevier Inc. All rights reserved.

Sugar Sweetened Beverage Consumption among Primary School Students: Influence of the Schools' Vicinity.

PubMed

Lebel, Alexandre; Morin, Pascale; Robitaille, Éric; Lalonde, Benoit; Florina Fratu, Ramona; Bisset, Sherri

2016-01-01

The purpose of the research was to explore the associations between the characteristics of schools' vicinity and the risk of sugar sweetened beverage (SSB) consumption in elementary students. Findings exposed an important variation in student's SSB consumption between schools. Schools with a lower socioeconomic status or in a densely built environment tend to have higher proportion of regular SSB drinkers. These characteristics of the school's vicinity partly explained the variation observed between them. We estimated that a student moving to a school with a higher proportion of SSB drinkers may increase his/her chances by 52% of becoming a daily consumer. Important changes in dietary preferences can occur when children are in contact with a new social environment. Findings also support the idea that dietary behaviors among children result from the complex interactions between biological, social, and environmental factors.

MEG evidence that the central auditory system simultaneously encodes multiple temporal cues.

PubMed

Simpson, Michael I G; Barnes, Gareth R; Johnson, Sam R; Hillebrand, Arjan; Singh, Krish D; Green, Gary G R

2009-09-01

Speech contains complex amplitude modulations that have envelopes with multiple temporal cues. The processing of these complex envelopes is not well explained by the classical models of amplitude modulation processing. This may be because the evidence for the models typically comes from the use of simple sinusoidal amplitude modulations. In this study we used magnetoencephalography (MEG) to generate source space current estimates of the steady-state responses to simple one-component amplitude modulations and to a two-component amplitude modulation. A two-component modulation introduces the simplest form of modulation complexity into the waveform; the summation of the two-modulation rates introduces a beat-like modulation at the difference frequency between the two modulation rates. We compared the cortical representations of responses to the one-component and two-component modulations. In particular, we show that the temporal complexity in the two-component amplitude modulation stimuli was preserved at the cortical level. The method of stimulus normalization that we used also allows us to interpret these results as evidence that the important feature in sound modulations is the relative depth of one modulation rate with respect to another, rather than the absolute carrier-to-sideband modulation depth. More generally, this may be interpreted as evidence that modulation detection accurately preserves a representation of the modulation envelope. This is an important observation with respect to models of modulation processing, as it suggests that models may need a dynamic processing step to effectively model non-stationary stimuli. We suggest that the classic modulation filterbank model needs to be modified to take these findings into account.

Time-alternating method based on single-sideband holography with half-zone-plate processing for the enlargement of viewing zones.

PubMed

Mishina, T; Okano, F; Yuyama, I

1999-06-10

The single-sideband method of holography, as is well known, cuts off beams that come from conjugate images for holograms produced in the Fraunhofer region and from objects with no phase components. The single-sideband method with half-zone-plate processing is also effective in the Fresnel region for beams from an object that has phase components. However, this method restricts the viewing zone to a narrow range. We propose a method to improve this restriction by time-alternating switching of hologram patterns and a spatial filter set on the focal plane of a reconstruction lens.

Anomalous temperature dependence of the IR spectrum of polyalanine

NASA Astrophysics Data System (ADS)

Helenius, V.; Korppi-Tommola, J.; Kotila, S.; Nieminen, J.; Lohikoski, R.; Timonen, J.

1997-12-01

We have studied the temperature dependence of the infrared spectra of acetanilide (ACN), tryptophan-(alanine) 15, and tyrosine-(alanine) 15. No sidebands of the amide-I vibration were observed in the polypeptides, but two anomalous sidebands of the NH stretch with a similar temperature dependence as that of the anomalous amide-I vibrational mode at 1650 cm -1 of crystalline ACN were detected. Fermi resonance combined with the appearance of a red-shifted sideband of NH stretch through coupling to lattice modes seems to explain this band structure. Observations are indicative of excitons that may occur in polypeptides as well as in single crystals of ACN.

Interannual and Spatial Variability in Maturity of Walleye Pollock Gadus chalcogrammus and Implications for Spawning Stock Biomass Estimates in the Gulf of Alaska

PubMed Central

Kruse, Gordon H.; Dorn, Martin W.

2016-01-01

Catch quotas for walleye pollock Gadus chalcogrammus, the dominant species in the groundfish fishery off Alaska, are set by applying harvest control rules to annual estimates of spawning stock biomass (SSB) from age-structured stock assessments. Adult walleye pollock abundance and maturity status have been monitored in early spring in Shelikof Strait in the Gulf of Alaska for almost three decades. The sampling strategy for maturity status is largely characterized as targeted, albeit opportunistic, sampling of trawl tows made during hydroacoustic surveys. Trawl sampling during pre-spawning biomass surveys, which do not adequately account for spatial patterns in the distribution of immature and mature fish, can bias estimated maturity ogives from which SSB is calculated. Utilizing these maturity data, we developed mixed-effects generalized additive models to examine spatial and temporal patterns in walleye pollock maturity and the influence of these patterns on estimates of SSB. Current stock assessment practice is to estimate SSB as the product of annual estimates of numbers at age, weight at age, and mean maturity at age for 1983-present. In practice, we found this strategy to be conservative for a time period from 2003–2013 as, on average, it underestimates SSB by a 4.7 to 11.9% difference when compared to our estimates of SSB that account for spatial structure or both temporal and spatial structure. Inclusion of spatially explicit information for walleye pollock maturity has implications for understanding stock reproductive biology and thus the setting of sustainable harvest rates used to manage this valuable fishery. PMID:27736982

Consumption of soda and other sugar-sweetened beverages by 2-year-olds: findings from a population-based survey.

PubMed

Garnett, Bernice Raveche; Rosenberg, Kenneth D; Morris, Daniel S

2013-10-01

To determine risk factors for consumption of soda and other sugar-sweetened beverages (SSB) among 2-year-old children. The analysis was performed using three linked data sets: the 2004-2005 Oregon Pregnancy Risk Assessment Monitoring Survey (PRAMS); its longitudinal follow-up, 2006-2007 Oregon PRAMS-2; and 2004-2005 Oregon birth certificates. PRAMS is a surveillance programme supported by the federal Centers for Disease Control and Prevention and implemented by participating state health departments. Using mixed methods, PRAMS surveys women 2-6 months after a live birth. Oregon PRAMS-2 re-interviews respondents shortly after the index child's second birthday. Oregon PRAMS oversamples minority women. Using monthly cohorts, we randomly selected 5851 women from the 2004-2005 birth certificates. In total 1911 women completed both PRAMS and PRAMS-2. The weighted response rate of PRAMS-2 was 43.5%. Almost half of mothers (49.9%) reported that their child drank SSB on at least 1 d/week. Mothers whose children drank SSB at least once weekly were more likely to have low income (adjusted OR=2.83, 95% CI 2.09, 3.83) and to eat out on ≥2 d/week (OR=2.11 %, 95% CI 1.66, 2.70). Hispanic and non-Hispanic black women were most likely to report that their child drank SSB at least once weekly. Half of mothers reported that their 2-year-old children drank SSB at least once weekly. Public health interventions and policies should address childhood SSB consumption including educating health-care providers and parents.

Identifying Financially Sustainable Pricing Interventions to Promote Healthier Beverage Purchases in Small Neighborhood Stores

PubMed Central

Kumanyika, Shiriki; Gittelsohn, Joel; Adam, Atif; Wong, Michelle S.; Mui, Yeeli; Lee, Bruce Y.

2018-01-01

Introduction Residents of low-income communities often purchase sugar-sweetened beverages (SSBs) at small, neighborhood “corner” stores. Lowering water prices and increasing SSB prices are potentially complementary public health strategies to promote more healthful beverage purchasing patterns in these stores. Sustainability, however, depends on financial feasibility. Because in-store pricing experiments are complex and require retailers to take business risks, we used a simulation approach to identify profitable pricing combinations for corner stores. Methods The analytic approach was based on inventory models, which are suitable for modeling business operations. We used discrete-event simulation to build inventory models that use data representing beverage inventory, wholesale costs, changes in retail prices, and consumer demand for 2 corner stores in Baltimore, Maryland. Model outputs yielded ranges for water and SSB prices that increased water demand without loss of profit from combined water and SSB sales. Results A 20% SSB price increase allowed lowering water prices by up to 20% while maintaining profit and increased water demand by 9% and 14%, for stores selling SSBs in 12-oz cans and 16- to 20-oz bottles, respectively. Without changing water prices, profits could increase by 4% and 6%, respectively. Sensitivity analysis showed that stores with a higher volume of SSB sales could reduce water prices the most without loss of profit. Conclusion Various combinations of SSB and water prices could encourage water consumption while maintaining or increasing store owners’ profits. This model is a first step in designing and implementing profitable pricing strategies in collaboration with store owners. PMID:29369758

The oxygen enhancement ratio for single- and double-strand breaks induced by tritium incorporated in DNA of cultured human T1 cells. Impact of the transmutation effect.

PubMed

Tisljar-Lentulis, G; Henneberg, P; Feinendegen, L E; Commerford, S L

1983-04-01

The effect of oxygen, expressed as the oxygen enhancement ratio (OER), on the number of single-strand breaks (SSB) and double-strand breaks (DSB) induced in DNA by the radioactive decay of tritium was measured in human T1 cells whose DNA had been labeled with tritium at carbon atom number 6 of thymidine. Decays were accumulated in vivo under aerobic conditions at 0-1 degrees C and at -196 degrees C and in a nitrogen atmosphere at 0-1 degrees C. The number of SSB and DSB produced was analyzed by sucrose gradient centrifugation. For each tritium decay there were 0.25 DSB in cells exposed to air at 0-1 degrees C and 0.07 in cells kept under nitrogen, indicating an OER of 3.6, a value expected for such low-LET radiation. However, for each tritium decay there were 1.25 SSB in cells exposed to air at 0-1 degrees C and 0.76 in cells kept under nitrogen indicating an OER of only 1.7. The corresponding values for 60Co gamma radiation, expressed as SSB per 100 eV absorbed energy, were 4.5 and 1.0, giving an OER of 4.5. The low OER value found for SSB induced by tritium decay can be explained if 31% of the total SSB produced in air result from transmutation by a mechanism which does not produce DSB and is unaffected by oxygen.

Identifying Financially Sustainable Pricing Interventions to Promote Healthier Beverage Purchases in Small Neighborhood Stores.

PubMed

Nau, Claudia; Kumanyika, Shiriki; Gittelsohn, Joel; Adam, Atif; Wong, Michelle S; Mui, Yeeli; Lee, Bruce Y

2018-01-25

Residents of low-income communities often purchase sugar-sweetened beverages (SSBs) at small, neighborhood "corner" stores. Lowering water prices and increasing SSB prices are potentially complementary public health strategies to promote more healthful beverage purchasing patterns in these stores. Sustainability, however, depends on financial feasibility. Because in-store pricing experiments are complex and require retailers to take business risks, we used a simulation approach to identify profitable pricing combinations for corner stores. The analytic approach was based on inventory models, which are suitable for modeling business operations. We used discrete-event simulation to build inventory models that use data representing beverage inventory, wholesale costs, changes in retail prices, and consumer demand for 2 corner stores in Baltimore, Maryland. Model outputs yielded ranges for water and SSB prices that increased water demand without loss of profit from combined water and SSB sales. A 20% SSB price increase allowed lowering water prices by up to 20% while maintaining profit and increased water demand by 9% and 14%, for stores selling SSBs in 12-oz cans and 16- to 20-oz bottles, respectively. Without changing water prices, profits could increase by 4% and 6%, respectively. Sensitivity analysis showed that stores with a higher volume of SSB sales could reduce water prices the most without loss of profit. Various combinations of SSB and water prices could encourage water consumption while maintaining or increasing store owners' profits. This model is a first step in designing and implementing profitable pricing strategies in collaboration with store owners.

Self-reported advertising exposure to sugar-sweetened beverages among US youth.

PubMed

Kumar, Gayathri; Onufrak, Stephen; Zytnick, Deena; Kingsley, Beverly; Park, Sohyun

2015-05-01

According to the Federal Trade Commission, in 2009, the top food category with teen-directed marketing expenditures was sugar-sweetened beverages (SSB). The present study reports on exposure to SSB advertisements using self-report data from adolescents. Cross-sectional study design using descriptive statistics to assess self-reported frequency of exposure to SSB advertisements and multivariable logistic regression to examine associations between frequency of SSB advertising exposure and sociodemographic variables. Online survey conducted at home. US adolescents aged 12-17 years (n 847). Among the surveyed adolescents, 42 % to 54 % reported seeing/hearing SSB advertisements ≥1 time/d. Those aged 14-15 years were more likely to report seeing/hearing soda, sports drink and energy drink advertisements ≥1 time/d than 16- to 17-year-olds. Males were more likely to report seeing/hearing sports drink advertising ≥1 time/d than females. Non-Hispanic black adolescents were more likely to report seeing/hearing fruit drink and sports drink advertisements ≥1 time/d than non-Hispanic white adolescents. Adolescents whose parents had high-school education or less were more likely to report seeing/hearing soda, fruit drink and energy drink advertisements ≥1 time/d than adolescents whose parents were college graduates. Almost half of the adolescents sampled reported daily SSB advertising exposure, with higher exposure among African Americans and adolescents with less educated parents. These data can help inform potential actions that decision makers might take, such as education of adolescents and their caregivers on the potential impact of beverage advertising, especially among groups at higher risk for obesity.

Consumption of sugar-sweetened beverages and artificially sweetened beverages from childhood to adulthood in relation to socioeconomic status - 15 years follow-up in Norway.

PubMed

Bolt-Evensen, Kathrine; Vik, Frøydis N; Stea, Tonje Holte; Klepp, Knut-Inge; Bere, Elling

2018-01-17

In Norway, social inequalities in health and health-related behaviors have been reported despite the well-developed welfare state. The objective of the present study was to analyze; (i) the development in frequency of consumption of sugar-sweetened beverages (SSB) and artificially sweetened beverages (ASB) from childhood to adulthood; (ii) socioeconomic inequalities in the consumption of SSB and ASB using different indicators of socioeconomic status (SES); (iii) time trends in potential disparities in SSB and ASB consumption among different socioeconomic groups to assess the development in socioeconomic inequality from childhood to adulthood. This study uses data from the Fruits and Vegetables Make the Marks (FVMM) longitudinal cohort, including participants (n = 437) from 20 random schools from two Norwegian counties. Data from the first survey in 2001 (mean age 11.8) and follow-up surveys in 2005 (mean age 15.5) and 2016 (mean age 26.5) were used. Consumption of SSB and ASB were measured using a food frequency questionnaire, which the participants completed at school in 2001 and 2005, and online in 2016. Various indicators of SES were included; in 2001, parental education and income were measured, in 2005, participants' educational intentions in adolescence were measured, and in 2016, participants' own education and income were measured. The main analyses conducted were linear mixed effects analysis of the repeated measures. Between 2001 and 2016, a decrease in frequency of consumption of SSB (2.8 v 1.3 times/week; p = < 0.001) and an increase in frequency of consumption of ASB (1.1 v 1.6 times/week; p = 0.002) were observed. Participants with a higher educational level in adulthood and higher educational intentions in adolescence had a significantly lower frequency of consumption of SSB at all time points (2001, 2005 and 2016). No significant widening (or narrowing) of inequalities were observed from childhood to adulthood. A decrease in consumption of SSB and an increase in consumption of ASB from childhood to adulthood were found. Participants with high SES consumed in general less SSB (but not ASB), however, results varied depending on SES indicator used. The established inequalities persisted from childhood to adulthood.

Proposal and performance analysis on the PDM microwave photonic link for the mm-wave signal with hybrid QAM-MPPM-RZ modulation

NASA Astrophysics Data System (ADS)

Tian, Bo; Zhang, Qi; Ma, Jianxin; Tao, Ying; Shen, Yufei; Wang, Yang; Zhang, Geng; Zhou, Wenmao; Zhao, Yi; Pan, Xiaolong

2018-07-01

A polarization division multiplexed (PDM) microwave photonic link for the millimeter (MM)-wave signal with hybrid modulation scheme is proposed in this paper, which is based on the combination of quadrature amplitude modulation, multi-pulse pulse-position modulation and return to zero modulation (QAM-MPPM-RZ). In this scheme, the two orthogonal polarization states enable simultaneous transmission of four data flows, which can provide different services for users according to the data rate requirement. To generate hybrid QAM-MPPM-RZ mm-wave signal, the QAM mm-wave signal is directly modulated by MPPM-RZ signal without using digital signal processing (DSP) devices, which reduces the overhead of the encoding process. Then, the generated QAM-MPPM-RZ mm-wave signal is transmitted in PDM microwave photonic link based on SSB modulation. The sparsity characteristic of QAM-MPPM-RZ not only improves the power efficiency, but also decreases the degradation caused by the fiber chromatic dispersion. The simulation results show that, under the constraint of the same transmitted data rate, the PDM microwave photonic link with 50 GHz QAM-MPPM-RZ mm-wave signal achieves much lower levels of bit-error rate than ordinary 32-QAM. In addition, the increase of laser linewidth brings no additional impact to the proposed scheme.

Expansion of linear range of Pound-Drever-Hall signal.

PubMed

Miyoki, Shinji; Telada, Souich; Uchiyama, Takashi

2010-10-01

We propose new solutions for expanding the linear signal range between the laser frequency deviation (or mirror position) and the voltage signal derived by the Pound-Drever-Hall (PDH) method for optical Fabry-Perot cavity resonance control. One solution is to perform not in-phase demodulation but near-Q-phase demodulation. Another solution is to take a suitable combination of signals demodulated by odd-harmonic modulation frequencies in the in phase. Although the PDH signal sensitivity will be diminished, the PDH signal linear range can be extended. From a practical standpoint, it is desirable that a sideband frequency for the PDH method is near the FP cavity resonance.

Polarization switch of four-wave mixing in a lawtunable fiber optical parametric oscillator.

PubMed

Yang, Kangwen; Ye, Pengbo; Zheng, Shikai; Jiang, Jieshi; Huang, Kun; Hao, Qiang; Zeng, Heping

2018-02-05

We reported the simultaneous generation and selective manipulation of scalar and cross-phase modulation instabilities in a fiber optical parametric oscillator. Numerical and experimental results show independent control of parametric gain by changing the input pump polarization state. The resonant cavity enables power enhancement of 45 dB for the spontaneous sidebands, generating laser pulses tunable from 783 to 791 nm and 896 to 1005 nm due to the combination of four-wave mixing, cascaded Raman scattering and other nonlinear effects. This gain controlled, wavelength tunable, fiber-based laser source may find applications in the fields of nonlinear biomedical imaging and stimulated Raman spectroscopy.

Obstacles and opportunities in the commercialization of the solid state electronic fluorescent lighting ballast

NASA Astrophysics Data System (ADS)

Johnson, D. R.; Marcus, A. A.; Campbell, R. S.; Sommers, P.; Skumatz, L.; Berk, B.; Petty, P.; Eschbach, C.

1981-10-01

A solid state ballast (SSB), which improves the efficiency of fluorescent lights, is described. The first generation of solid state electronic ballasts was developed and the technology was transferred to the private sector. The opportunities for rapid dissemination of this technology into the marketplace is examined. Product characteristics and their influence on the commercialization of the SSB, a description of the technology delivery system presently used by the ballast industry, an analysis of the market for SSB, and identification of some high leverage opportunities to accelerate the commercialization process are included.

Ssb1 chaperone is a [PSI+] prion-curing factor.

PubMed

Chacinska, A; Szczesniak, B; Kochneva-Pervukhova, N V; Kushnirov, V V; Ter-Avanesyan, M D; Boguta, M

2001-04-01

Yeast SUP7' or SUP11 nonsense suppressors have no phenotypic expression in strains deficient in the isopentenylation of A37 in tRNA. Here we show that such strains spontaneously produce cells with a nonsense suppressor phenotype which is related to the cytoplasmically inherited determinant and manifests all the key features of the [PSI+] prion. A screen of a multicopy yeast genomic library for genes that inactivate the [PSI+]-related suppressor phenotype resulted in the isolation of the SSB1 gene. Moreover, we demonstrate that multicopy plasmid encoding the Ssb1 chaperone cures cells of the [PSI+] prion.

International application of sugar-sweetened beverage (SSB) taxation in obesity reduction: factors that may influence policy effectiveness in country-specific contexts.

PubMed

Jou, Judy; Techakehakij, Win

2012-09-01

Sugar-sweetened beverage (SSB) taxation is becoming of increasing interest as a policy aimed at addressing the rising prevalence of obesity in many countries. Preliminary evidence indicates its potential to not only reduce obesity prevalence, but also generate public revenue. However, differences in country-specific contexts create uncertainties in its possible outcomes. This paper urges careful consideration of country-specific characteristics by suggesting three points in particular that may influence the effectiveness of a volume-based soft drink excise tax: population obesity prevalence, soft drink consumption levels, and existing baseline tax rates. Data from 19 countries are compared with regard to each point. The authors suggest that SSB or soft drink taxation policy may be more effective in reducing obesity prevalence where existing obesity prevalence and soft drink consumption levels are high. Conversely, in countries where the baseline tax rate is already considered high, SSB taxation may not have a noticeable impact on consumption patterns or obesity prevalence, and may incur negative feedback from the beverage industry or the general public. Thorough evaluation of these points is recommended prior to adopting SSB or soft drink taxation as an obesity reduction measure in any given country. Copyright © 2012 Elsevier Ireland Ltd. All rights reserved.

Do You Know What Your Kids Are Drinking? Evaluation of a Media Campaign to Reduce Consumption of Sugar-Sweetened Beverages.

PubMed

Bleakley, Amy; Jordan, Amy; Mallya, Giridhar; Hennessy, Michael; Piotrowski, Jessica Taylor

2017-01-01

This study evaluates a citywide media campaign that targeted reducing sugar-sweetened beverage (SSB) consumption as a strategy for addressing obesity. Rolling cross-sectional survey data, collected before and during the media campaign, with 1367 parents to assess exposure to and effect of a televised public service advertisement (TV PSA) developed using a reasoned action approach. Televised public service advertisement campaign created by the Philadelphia Department of Public Health and disseminated on cable television channels within the Philadelphia market. Philadelphia parents/primary caregivers with a child between the ages of 3 and 16. Linear regression analysis shows that exposure to the TV PSA was significantly associated with intention to substitute nonsugary drinks for SSBs for the parent ( P = .04) and the child ( P = .02). The effect of exposure on intention to reduce child's SSB consumption increased the longer the campaign was in the field. Exposure was also significantly associated with the belief that reducing SSB consumption decreases the risk of diabetes ( P = .04) and was significantly negatively related to the belief that reducing SSB consumption would make mealtimes less enjoyable ( P = .04). These findings suggest that a theory-based mass media campaign can achieve positive changes in intention related to SSB consumption by changing relevant and salient underlying beliefs.

Reducing Sugar-Sweetened Beverage Consumption by Providing Caloric Information: How Black Adolescents Alter Their Purchases and Whether the Effects Persist

PubMed Central

Barry, Colleen L.; Gary-Webb, Tiffany L.; Herring, Bradley J.

2014-01-01

Objectives. We examined the ways in which adolescents altered the type and size of their purchases of sugar-sweetened beverages (SSBs), together with whether the effects persisted after removing caloric information signs in stores. Methods. We used a case-crossover design with 6 stores located in low-income Black neighborhoods in Baltimore, Maryland, from 2012 to 2013. The intervention used 1 of 4 randomly posted signs with caloric information: absolute calories, number of teaspoons of sugar, and number of minutes of running or miles of walking necessary to burn off a beverage. We collected data for 4516 purchases by Black adolescents, including both baseline and postintervention periods with no signs posted. Results. We found that providing caloric information significantly reduced the number of total beverage calories purchased, the likelihood of buying an SSB, and the likelihood of buying an SSB greater than 16 ounces (P < .05). After removing the signs, the quantity, volume, and number of calories from SSB purchases remained lower than baseline (P < .05). Conclusions. Providing caloric information was associated with purchasing a smaller SSB, switching to a beverage with no calories, or opting to not purchase a beverage; there was a persistent effect on reducing SSB purchases after signs were removed. PMID:25322298

Reducing sugar-sweetened beverage consumption by providing caloric information: how Black adolescents alter their purchases and whether the effects persist.

PubMed

Bleich, Sara N; Barry, Colleen L; Gary-Webb, Tiffany L; Herring, Bradley J

2014-12-01

We examined the ways in which adolescents altered the type and size of their purchases of sugar-sweetened beverages (SSBs), together with whether the effects persisted after removing caloric information signs in stores. We used a case-crossover design with 6 stores located in low-income Black neighborhoods in Baltimore, Maryland, from 2012 to 2013. The intervention used 1 of 4 randomly posted signs with caloric information: absolute calories, number of teaspoons of sugar, and number of minutes of running or miles of walking necessary to burn off a beverage. We collected data for 4516 purchases by Black adolescents, including both baseline and postintervention periods with no signs posted. We found that providing caloric information significantly reduced the number of total beverage calories purchased, the likelihood of buying an SSB, and the likelihood of buying an SSB greater than 16 ounces (P < .05). After removing the signs, the quantity, volume, and number of calories from SSB purchases remained lower than baseline (P < .05). Providing caloric information was associated with purchasing a smaller SSB, switching to a beverage with no calories, or opting to not purchase a beverage; there was a persistent effect on reducing SSB purchases after signs were removed.

Sugar-Sweetened Beverage, Obesity, and Type 2 Diabetes in Children and Adolescents: Policies, Taxation, and Programs.

PubMed

Yoshida, Yilin; Simoes, Eduardo J

2018-04-18

Obesity has grown at an alarming rate in children and adolescents. Concurrently, consumption on sugar-sweetened beverages (SSBs) also rose significantly. This review provides an overview of obesity and type 2 diabetes mellitus (T2DM) related to SSBs and current policies restricting SSBs in schools, school-based interventions, and taxation on reducing SSB intake and obesity. We also discuss challenges of and future steps for these initiatives. Clinical and epidemiological studies suggest a strong association between SSB intake and obesity and T2DM. School food policies have been initiated at federal, state, and local levels. School-based interventions have shown positive effects on SSB intake and obesity reduction. Taxation on SSBs is promising in combating obesity and in generating revenue. Challenges towards compliance and implementation of the policies and programs exist. The relationship between SSB and obesity and T2DM is a complex problem which requires comprehensive solutions. Continued efforts in restricting SSBs in schools are needed. Intervention programs should be tailored to age, gender, language, and culture and involve participation from families and local communities. Taxation can reduce SSB consumption by direct economic incentive, earmarking revenues to support healthy foods, and sending negative message. However, a higher tax rate may be necessary to have a measurable effect on weight.

The Canadian Bandaging Trial: Evidence-informed leg ulcer care and the effectiveness of two compression technologies

PubMed Central

2011-01-01

Background Objective: To determine the relative effectiveness of evidence-informed practice using two high compression systems: four-layer (4LB) and short-stretch bandaging (SSB) in community care of venous leg ulcers. Design and Setting: Pragmatic, multi-centre, parallel-group, open-label, randomized controlled trial conducted in 10 centres. Cognitively intact adults (≥18 years) referred for community care (home or clinic) with a venous ulceration measuring ≥0.7cm and present for ≥1 week, with an ankle brachial pressure index (ABPI) ≥0.8, without medication-controlled Diabetes Mellitus or a previous failure to improve with either system, were eligible to participate. Methods Consenting individuals were randomly allocated (computer-generated blocked randomization schedule) to receive either 4LB or SSB following an evidence-informed protocol. Primary endpoint: time-to- healing of the reference ulcer. Secondary outcomes: recurrence rates, health-related quality of life (HRQL), pain, and expenditures. Results 424 individuals were randomized (4LB n = 215; SSB n = 209) and followed until their reference ulcer was healed (or maximum 30 months). An intent-to-treat analysis was conducted on all participants. Median time to ulcer healing in the 4LB group was 62 days [95% confidence interval (CI) 51 to 73], compared with 77 days (95% CI 63 to 91) in the SSB group. The unadjusted Kaplan-Meier curves revealed the difference in the distribution of cumulative healing times was not significantly different between group (log rank χ2 = 0.001, P = 0.98) nor ulcers recurrence (4LB, 10.1%; SSB, 13.3%; p = 0.345). Multivariable Cox Proportional Hazard Modeling also showed no significant between-bandage differences in healing time after controlling for significant covariates (p = 0.77). At 3-months post-baseline there were no differences in pain (no pain: 4LB, 22.7%; SSB, 26.7%; p = 0.335), or HRQL (SF-12 Mental Component Score: 4LB, 55.1; SSB, 55.8; p = 0.615; SF-12 Physical Component Score: 4LB, 39.0; SSB, 39.6; p = 0.675). The most common adverse events experienced by both groups included infection, skin breakdown and ulcer deterioration. Conclusions The Canadian Bandaging Trial revealed that in the practice context of trained RNs using an evidence-informed protocol, the choice of bandage system (4LB and SSB) does not materially affect healing times, recurrence rates, HRQL, or pain. From a community practice perspective, this is positive news for patient-centred care allowing individual/family and practitioner choice in selecting compression technologies based on circumstances and context. Trial registration clinicaltrials.gov Identifier: NCT00202267 PMID:21995267

Optical frequency upconversion technique for transmission of wireless MIMO-type signals over optical fiber.

PubMed

Shaddad, R Q; Mohammad, A B; Al-Gailani, S A; Al-Hetar, A M

2014-01-01

The optical fiber is well adapted to pass multiple wireless signals having different carrier frequencies by using radio-over-fiber (ROF) technique. However, multiple wireless signals which have the same carrier frequency cannot propagate over a single optical fiber, such as wireless multi-input multi-output (MIMO) signals feeding multiple antennas in the fiber wireless (FiWi) system. A novel optical frequency upconversion (OFU) technique is proposed to solve this problem. In this paper, the novel OFU approach is used to transmit three wireless MIMO signals over a 20 km standard single mode fiber (SMF). The OFU technique exploits one optical source to produce multiple wavelengths by delivering it to a LiNbO3 external optical modulator. The wireless MIMO signals are then modulated by LiNbO3 optical intensity modulators separately using the generated optical carriers from the OFU process. These modulators use the optical single-sideband with carrier (OSSB+C) modulation scheme to optimize the system performance against the fiber dispersion effect. Each wireless MIMO signal is with a 2.4 GHz or 5 GHz carrier frequency, 1 Gb/s data rate, and 16-quadrature amplitude modulation (QAM). The crosstalk between the wireless MIMO signals is highly suppressed, since each wireless MIMO signal is carried on a specific optical wavelength.

Feasibility and acceptability of a novel, computerized screening and brief intervention (SBI) for alcohol and sweetened beverage use in pregnancy.

PubMed

Nayak, Madhabika B; Korcha, Rachael A; Kaskutas, Lee A; Kaskustas, Lee A; Avalos, Lyndsay A

2014-11-25

Recommended screening and brief intervention (SBI) for alcohol use during pregnancy is impeded by high patient loads and limited resources in public health settings. We evaluated the feasibility, acceptability and validity of a new self-administered, single-session, bilingual, computerized Screening and Brief Intervention (SBI) program for alcohol and sugar sweetened beverage (SSB) use in pregnancy. We developed and tested the computerized SBI program at a public health clinic with 290 pregnant women. Feasibility, acceptability, and validity measures were included in the program which had several modules, including those on demographics, health and beverage use. Time to complete the program and user experience items were used to determine program feasibility and acceptability. Validity analyses compared proportions of prenatal alcohol use identified by the program versus in-person screening by clinic staff. Most program users (87%, n = 251) completed the entire program; 91% (n = 263) completed the key screening and brief intervention modules. Most users also completed the program in ten to fifteen minutes. Program users reported that the program was easy to use (97%), they learned something new (88%), and that they would share what they learned with others (83%) and with their doctors or clinic staff (76%). Program acceptability did not differ by age, education, or type of beverage intervention received. The program identified alcohol use in pregnancy among 21% of users, a higher rate than the 13% (p < .01) found via screening by clinic staff. Computerized Screening and Brief Intervention for alcohol and SSB use in public health clinics is feasible and acceptable to English and Spanish speaking pregnant women and can efficiently identify prenatal alcohol use.

ACSB: A minimum performance assessment

NASA Technical Reports Server (NTRS)

Jones, Lloyd Thomas; Kissick, William A.

1988-01-01

Amplitude companded sideband (ACSB) is a new modulation technique which uses a much smaller channel width than does conventional frequency modulation (FM). Among the requirements of a mobile communications system is adequate speech intelligibility. This paper explores this aspect of minimum required performance. First, the basic principles of ACSB are described, with emphasis on those features that affect speech quality. Second, the appropriate performance measures for ACSB are reviewed. Third, a subjective voice quality scoring method is used to determine the values of the performance measures that equate to the minimum level of intelligibility. It is assumed that the intelligibility of an FM system operating at 12 dB SINAD represents that minimum. It was determined that ACSB operating at 12 dB SINAD with an audio-to-pilot ratio of 10 dB provides approximately the same intelligibility as FM operating at 12 dB SINAD.

Frequency-Domain Analysis of Diffusion-Cooled Hot-Electron Bolometer Mixers

NASA Technical Reports Server (NTRS)

Skalare, A.; McGrath, W. R.; Bumble, B.; LeDuc, H. G.

1998-01-01

A new theoretical model is introduced to describe heterodyne mixer conversion efficiency and noise (from thermal fluctuation effects) in diffusion-cooled superconducting hot-electron bolometers. The model takes into account the non-uniform internal electron temperature distribution generated by Wiedemann-Franz heat conduction, and accepts for input an arbitrary (analytical or experimental) superconducting resistance-versus- temperature curve. A non-linear large-signal solution is solved iteratively to calculate the temperature distribution, and a linear frequency-domain small-signal formulation is used to calculate conversion efficiency and noise. In the small-signal solution the device is discretized into segments, and matrix algebra is used to relate the heating modulation in the segments to temperature and resistance modulations. Matrix expressions are derived that allow single-sideband mixer conversion efficiency and coupled noise power to be directly calculated. The model accounts for self-heating and electrothermal feedback from the surrounding bias circuit.

100 Gb/s optical discrete multi-tone transceivers for intra- and inter-datacenter networks

NASA Astrophysics Data System (ADS)

Okabe, Ryo; Tanaka, Toshiki; Nishihara, Masato; Kai, Yutaka; Takahara, Tomoo; Liu, Bo; Li, Lei; Tao, Zhenning; Rasmussen, Jens C.

2016-03-01

Discrete multi-tone (DMT) technology is an attractive modulation technology for short-reach application due to its high spectral efficiency and simple configuration. In this paper, we first explain the features of DMT technology then discuss the impact of fiber dispersion and chirp on the frequency responses of the DMT signal and the importance in the relationship between chirp and the optical transmission band. Next, we explain our experiments of 100-Gb/s DMT transmission of 10 km in the O-band using directly modulated lasers for low-cost application. In an inter-datacenter network of more than several tens of kilometers, fiber dispersion mainly limits system performance. We also discuss our experiment of 100-Gb/s DMT transmission up to 100 km in the C-band without a dispersion compensator by using vestigial sideband spectrum shaping and nonlinear compensation.

Highly integrated optical heterodyne phase-locked loop with phase/frequency detection.

PubMed

Lu, Mingzhi; Park, Hyunchul; Bloch, Eli; Sivananthan, Abirami; Bhardwaj, Ashish; Griffith, Zach; Johansson, Leif A; Rodwell, Mark J; Coldren, Larry A

2012-04-23

A highly-integrated optical phase-locked loop with a phase/frequency detector and a single-sideband mixer (SSBM) has been proposed and demonstrated for the first time. A photonic integrated circuit (PIC) has been designed, fabricated and tested, together with an electronic IC (EIC). The PIC integrates a widely-tunable sampled-grating distributed-Bragg-reflector laser, an optical 90 degree hybrid and four high-speed photodetectors on the InGaAsP/InP platform. The EIC adds a single-sideband mixer, and a digital phase/frequency detector, to provide single-sideband heterodyne locking from -9 GHz to 7.5 GHz. The loop bandwith is 400 MHz. © 2012 Optical Society of America

Broadband MAS NMR spectroscopy in the low-power limit

NASA Astrophysics Data System (ADS)

Sanders, Kevin J.; Pell, Andrew J.; Wegner, Sebastian; Grey, Clare P.; Pintacuda, Guido

2018-04-01

We investigate the performance of broadband adiabatic inversion pulses in the high-power (short high-powered adiabatic pulse, SHAP) and low-power (single-sideband-selective adiabatic pulse, S3AP) RF regimes on a spin system subjected to large anisotropic interactions. We show by combined experimental results and spin dynamics simulations that when the magic-angle spinning rate exceeds 100 kHz S3APs begin outperforming SHAPs. This is especially true for low-gamma nuclei, such as 6 Li in paramagnetic Li-ion battery materials. Finally, we show how S3APs can be improved by combining multiple waveforms sweeping over multiple sidebands simultaneously, in order to produce inverted sideband profiles free from intensity biasing.

The ribosome-associated complex antagonizes prion formation in yeast.

PubMed

Amor, Alvaro J; Castanzo, Dominic T; Delany, Sean P; Selechnik, Daniel M; van Ooy, Alex; Cameron, Dale M

2015-01-01

The number of known fungal proteins capable of switching between alternative stable conformations is steadily increasing, suggesting that a prion-like mechanism may be broadly utilized as a means to propagate altered cellular states. To gain insight into the mechanisms by which cells regulate prion formation and toxicity we examined the role of the yeast ribosome-associated complex (RAC) in modulating both the formation of the [PSI(+)] prion - an alternative conformer of Sup35 protein - and the toxicity of aggregation-prone polypeptides. The Hsp40 RAC chaperone Zuo1 anchors the RAC to ribosomes and stimulates the ATPase activity of the Hsp70 chaperone Ssb. We found that cells lacking Zuo1 are sensitive to over-expression of some aggregation-prone proteins, including the Sup35 prion domain, suggesting that co-translational protein misfolding increases in Δzuo1 strains. Consistent with this finding, Δzuo1 cells exhibit higher frequencies of spontaneous and induced prion formation. Cells expressing mutant forms of Zuo1 lacking either a C-terminal charged region required for ribosome association, or the J-domain responsible for Ssb ATPase stimulation, exhibit similarly high frequencies of prion formation. Our findings are consistent with a role for the RAC in chaperoning nascent Sup35 to regulate folding of the N-terminal prion domain as it emerges from the ribosome.

MoYvh1 subverts rice defense through functions of ribosomal protein MoMrt4 in Magnaporthe oryzae.

PubMed

Liu, Xinyu; Yang, Jie; Qian, Bin; Cai, Yongchao; Zou, Xi; Zhang, Haifeng; Zheng, Xiaobo; Wang, Ping; Zhang, Zhengguang

2018-04-01

The accumulation of the reactive oxygen species (ROS) in rice is important in its interaction with the rice blast fungus Magnaporthe oryzae during which the pathogen scavenges ROS through the production of extracellular enzymes that promote blast. We previously characterized the MoYvh1 protein phosphatase from M. oryzae that plays a role in scavenging of ROS. To understand the underlying mechanism, we found that MoYvh1 is translocated into the nucleus following oxidative stress and that this translocation is dependent on MoSsb1 and MoSsz1 that are homologous to heat-shock protein 70 (Hsp70) proteins. In addition, we established a link between MoYvh1 and MoMrt4, a ribosome maturation factor homolog whose function also involves shuttling between the cytoplasm and the nucleus. Moreover, we found that MoYvh1 regulates the production of extracellular proteins that modulate rice-immunity. Taking together, our evidence suggests that functions of MoYvh1 in regulating ROS scavenging require its nucleocytoplasmic shuttling and the partner proteins MoSsb1 and MoSsz1, as well as MoMrt4. Our findings provide novel insights into the mechanism by which M. oryzae responds to and subverts host immunity through the regulation of ribosome biogenesis and protein biosynthesis.

Insights into the simultaneous removal of Cr6+ and Pb2+ by a novel sewage sludge-derived biochar immobilized nanoscale zero valent iron: Coexistence effect and mechanism.

PubMed

Diao, Zeng-Hui; Du, Jian-Jun; Jiang, Dan; Kong, Ling-Jun; Huo, Wen-Yi; Liu, Cui-Mei; Wu, Qi-Hang; Xu, Xiang-Rong

2018-06-13

Cr 6+ and Pb 2+ are both highly toxic pollutants and commonly co-exist in some industrial effluents and contaminated waters. In this study, simultaneous removal of Cr 6+ and Pb 2+ by a novel sewage sludge-derived biochar immobilized nanoscale zero-valent iron (SSB-nZVI) was systematically investigated. It was well demonstrated that a porous structure was successfully formed on the SSB-nZVI when the starch was used as an additive. A synergistic effect on the adsorption and reduction over the SSB-nZVI was achieved, resulting in nearly 90 and 82% of Cr 6+ and Pb 2+ removal within 30 min, respectively. Cr 6+ was reduced prior to Pb 2+ . A low pH could accelerate the corrosion of nZVI as well as phosphate leaching. When Malachite green was added as a coexisting organic pollutant, its effective removal was found due to the formation of a Fenton-like system. The SSB-nZVI could be run consecutively three times with a relatively satisfactory performance. Most of Cr 6+ was converted into Cr 2 O 3 and Cr(OH) 3 on the SSB-nZVI surface, whereas most of Pb 2+ species existed as Pb(OH) 2 (or PbO). A possible reaction mechanism on the SSB-nZVI involved the adsorption, reduction and precipitation of both Cr 6+ and Pb 2+ over the particles. Present study sheds light on the insight of the fate and transport of Cr 6+ and Pb 2+ in aquatic environment, as well provides helpful guide for the remediation of coexistence of pollutants in real applications. Copyright © 2018 Elsevier B.V. All rights reserved.

Sexually antagonistic selection on genetic variation underlying both male and female same-sex sexual behavior.

PubMed

Berger, David; You, Tao; Minano, Maravillas R; Grieshop, Karl; Lind, Martin I; Arnqvist, Göran; Maklakov, Alexei A

2016-05-13

Intralocus sexual conflict, arising from selection for different alleles at the same locus in males and females, imposes a constraint on sex-specific adaptation. Intralocus sexual conflict can be alleviated by the evolution of sex-limited genetic architectures and phenotypic expression, but pleiotropic constraints may hinder this process. Here, we explored putative intralocus sexual conflict and genetic (co)variance in a poorly understood behavior with near male-limited expression. Same-sex sexual behaviors (SSBs) generally do not conform to classic evolutionary models of adaptation but are common in male animals and have been hypothesized to result from perception errors and selection for high male mating rates. However, perspectives incorporating sex-specific selection on genes shared by males and females to explain the expression and evolution of SSBs have largely been neglected. We performed two parallel sex-limited artificial selection experiments on SSB in male and female seed beetles, followed by sex-specific assays of locomotor activity and male sex recognition (two traits hypothesized to be functionally related to SSB) and adult reproductive success (allowing us to assess fitness consequences of genetic variance in SSB and its correlated components). Our experiments reveal both shared and sex-limited genetic variance for SSB. Strikingly, genetically correlated responses in locomotor activity and male sex-recognition were associated with sexually antagonistic fitness effects, but these effects differed qualitatively between male and female selection lines, implicating intralocus sexual conflict at both male- and female-specific genetic components underlying SSB. Our study provides experimental support for the hypothesis that widespread pleiotropy generates pervasive intralocus sexual conflict governing the expression of SSBs, suggesting that SSB in one sex can occur due to the expression of genes that carry benefits in the other sex.

The effect of the air-blowing step on the technique sensitivity of four different adhesive systems.

PubMed

Spreafico, Diego; Semeraro, Stefano; Mezzanzanica, Dario; Re, Dino; Gagliani, Massimo; Tanaka, Toru; Sano, Hidehiko; Sidhu, Sharanbir K

2006-03-01

To evaluate the technique sensitivity of four different adhesive systems using different air-blowing pressure. Four adhesive systems were employed: Clearfil SE Bond [SE] (Kuraray, Japan), G-Bond [GB] (GC Corporation, Japan), Adper Prompt L-Pop [LP] (3M ESPE, USA) and an experimental adhesive, SSB-200 [SSB] (Kuraray, Japan). Twenty-four extracted molars were used. After grinding the coronal enamel surface, the teeth were divided into two equal groups. The first group's teeth were randomly assigned for bonding with the different adhesives using gentle air-blowing (g). For the teeth of the second group, the four adhesive systems were applied using strong air-blowing (s). After storage overnight in 37 degrees C water, the bonded specimens were sectioned into sticks (1 mm x 1 mm wide), which were subjected to microtensile bond strength testing (microTBS) at a crosshead speed of 1 mm/min. The load at failure of each specimen was recorded and the data were analyzed by one-way ANOVA and Tukey HSD tests. The surfaces of the fractured specimens were observed using SEM to determine the failure mode. The results of the microTBS test showed that the highest bond strengths tended to be with SE for both gentle and strong air-blowing, and the significantly lowest for SSB with strong air streaming. Comparing the two techniques, significant differences were noted only for SSB-200 (P < 0.05). For each material, the SEM evaluation did not show distinct differences in the nature of the fractures between the two techniques, except for SSB-200. The adhesives tested are not technique sensitive, except SSB-200, with regards to the air-blowing step.

Susceptibility to Food Advertisements and Sugar-Sweetened Beverage Intake in Non-Hispanic Black and Non-Hispanic White Adolescents.

PubMed

Cervi, Meredith M; Agurs-Collins, Tanya; Dwyer, Laura A; Thai, Chan L; Moser, Richard P; Nebeling, Linda C

2017-08-01

Obesity among adolescents in the United States has risen by 16% in the past 30 years. One important contributing factor may be the increased consumption of sugar sweetened beverages (SSBs), which is encouraged by advertisements for unhealthy foods and drinks that are targeted to adolescents. The purpose of this analysis was to determine the association between susceptibility to food and drink advertisements and sugar-sweetened beverage (SSB) consumption in non-Hispanic black (NHB) and non-Hispanic white (NHW) adolescents and to examine if BMI is associated with SSB consumption. Data were obtained from 765 NHB and NHW of ages 14-17 who were surveyed in the Family Life, Activity, Sun, Health, and Eating study sponsored by the National Cancer Institute. Two weighted adjusted logistic regression models were conducted. The first examined the associations of advertisement susceptibility, race, and BMI with SSB consumption. The second examined the associations of race and BMI with advertisement susceptibility. Adolescents with high advertisement susceptibility were more likely to consume at least one SSB daily (OR 1.73, 95% CI 1.21, 2.47). Additionally, non-Hispanic blacks were more likely to consume at least one SSB daily (OR 1.75, 95% CI 1.08, 2.85) and more likely to be highly susceptible to advertisements (OR 1.72, 95% CI 1.19, 2.48) than non-Hispanic whites. No significant associations were found between BMI and advertising susceptibility or BMI and daily SSB consumption. One approach to addressing the consumption of SSBs may be to reduce advertising that markets unhealthy food and beverages to adolescents and minorities.

Familial and individual predictors of obesity and insulin resistance in urban Hispanic children.

PubMed

Santiago-Torres, M; Cui, Y; Adams, A K; Allen, D B; Carrel, A L; Guo, J Y; Delgado-Rendon, A; LaRowe, T L; Schoeller, D A

2016-02-01

High intake of sugar-sweetened beverages (SSB) has been suggested to contribute to the pediatric obesity epidemic, however, how the home food environment influence children's intake of SSB among Hispanic families is still poorly understood. To evaluate the relationships between the home food environment and Hispanic children's diet in relation to weight status and insulin resistance (IR). A food frequency questionnaire was administered to 187 Hispanic children (ages 10 to 14 years) and anthropometrics were measured. IR was estimated from fasting insulin and glucose levels using the homeostasis model assessment of insulin resistance (HOMAIR ). Parents reported on family demographics and the home food environment. A structural equation modelling approach was applied to examine the hypothesized relationships among variables. The prevalence of childhood overweight and obesity was 52.8% and it was positively associated with HOMAIR (β = 0.687, P < .0001). Children's SSB consumption was positively associated with children's body mass index z-score (β = 0.151, P < 0.05) and subsequently to HOMAIR . Children's SSB consumption was predicted by home availability (β = 0.191) and parental intake of SSB (β = 0.419) (P < 0.05). The model fit indices [χ(2)  = 45.821 (d.f. = 30, P > 0.01 and < 0.05), χ(2) /d.f. = 1.53, root mean square error of approximation = 0.053 (90% confidence interval = 0.016, 0.082), comparative fit index = 0.904] suggested a satisfactory goodness-of-fit. The home food environment and parental diet seem to play an important role in the children's access to and intake of SSB, which in turn predicted children's weight status. © 2015 World Obesity.

Effects of Low versus High Glycemic Index Sugar-Sweetened Beverages on Postprandial Vasodilatation and Inactivity-Induced Impairment of Glucose Metabolism in Healthy Men

PubMed Central

Keller, Judith; Kahlhöfer, Julia; Peter, Andreas; Bosy-Westphal, Anja

2016-01-01

Intake of sugar-sweetened beverages (SSB) may contribute to cardiovascular risk. The aim of this study was to investigate whether functional sugars with low compared to high glycemic index (GI) have beneficial effects on arterial stiffness during a period of low-physical activity. In a controlled cross-over dietary intervention (55% CHO, 30% fat, 15% protein), 13 healthy men (age: 23.7 ± 2.2 years, body mass index: 23.6 ± 1.9 kg/m2) completed 2 × 1 week of low physical activity following 1 week of normal physical activity (2363 ± 900 vs. 11,375 ± 3124 steps/day). During inactive phases participants consumed either low-GI (isomaltulose) or high-GI SSB (maltodextrin-sucrose), providing 20% of energy requirements. Postprandial vasodilatation (augmentation index, AIx), insulin sensitivity (IS) and Glucagon-like-peptide 1 (GLP-1) responses were measured during a meal test before and after SSB-intervention. Compared to maltodextrin-sucrose-SSB, postprandial vasodilatation was prolonged (AIx after 120 min: 9.9% ± 4.3% vs. 11.4% ± 3.7%, p < 0.05) and GLP-1 secretion was higher with isomaltulose-SSB (total area under the GLP-1 curve (tAUCGLP)-1: 8.0 ± 4.4 vs. 5.4 ± 3.4 pM × 3 h; p < 0.05). One week of low-physical activity led to impaired IS that was attenuated with low-GI SSB consumption, but did not affect arterial stiffness (p > 0.05). Higher postprandial GLP-1 secretion after intake of low compared to high-GI beverages may contribute to improved postprandial vasodilatation. Although one week of low-physical activity led to marked impairment in IS, it had no effect on arterial stiffness in healthy men. PMID:27973411

Effects of Low versus High Glycemic Index Sugar-Sweetened Beverages on Postprandial Vasodilatation and Inactivity-Induced Impairment of Glucose Metabolism in Healthy Men.

PubMed

Keller, Judith; Kahlhöfer, Julia; Peter, Andreas; Bosy-Westphal, Anja

2016-12-10

Intake of sugar-sweetened beverages (SSB) may contribute to cardiovascular risk. The aim of this study was to investigate whether functional sugars with low compared to high glycemic index (GI) have beneficial effects on arterial stiffness during a period of low-physical activity. In a controlled cross-over dietary intervention (55% CHO, 30% fat, 15% protein), 13 healthy men (age: 23.7 ± 2.2 years, body mass index: 23.6 ± 1.9 kg/m²) completed 2 × 1 week of low physical activity following 1 week of normal physical activity (2363 ± 900 vs. 11,375 ± 3124 steps/day). During inactive phases participants consumed either low-GI (isomaltulose) or high-GI SSB (maltodextrin-sucrose), providing 20% of energy requirements. Postprandial vasodilatation (augmentation index, AIx), insulin sensitivity (IS) and Glucagon-like-peptide 1 (GLP-1) responses were measured during a meal test before and after SSB-intervention. Compared to maltodextrin-sucrose-SSB, postprandial vasodilatation was prolonged (AIx after 120 min: 9.9% ± 4.3% vs. 11.4% ± 3.7%, p < 0.05) and GLP-1 secretion was higher with isomaltulose-SSB (total area under the GLP-1 curve (tAUC GLP )-1: 8.0 ± 4.4 vs. 5.4 ± 3.4 pM × 3 h; p < 0.05). One week of low-physical activity led to impaired IS that was attenuated with low-GI SSB consumption, but did not affect arterial stiffness ( p > 0.05). Higher postprandial GLP-1 secretion after intake of low compared to high-GI beverages may contribute to improved postprandial vasodilatation. Although one week of low-physical activity led to marked impairment in IS, it had no effect on arterial stiffness in healthy men.

The relationship between health-related knowledge and sugar-sweetened beverage intake among US adults.

PubMed

Park, Sohyun; Onufrak, Stephen; Sherry, Bettylou; Blanck, Heidi M

2014-07-01

Because there is limited information on associations between health-related knowledge and sugar-sweetened beverage (SSB) intake, our cross-sectional study examined this question using the 2010 HealthStyles Survey data for 3,926 adults (aged ≥18 years). Multivariable logistic regression analysis was used to estimate the adjusted odds ratios and 95% CIs for drinking SSBs ≥2 times per day. About 31% of adults consumed SSBs ≥1 time per day, with 20% doing so ≥2 times per day. About eight of 10 adults agreed that drinking SSBs can contribute to weight gain, yet, eight of 10 adults in this study did not know the actual kilocalorie content of a 24-oz fountain soda. After controlling for age, sex, race/ethnicity, education level, annual household income, and geographic region, the odds for drinking SSBs ≥2 times per day were significantly higher among adults who neither agreed nor disagreed (ie, were neutral) that drinking SSBs can contribute to weight gain (odds ratio 1.61, 95% CI 1.15 to 2.25 vs agree); however, knowledge about the energy content of regular soda was not associated with SSB intake. Our finding that knowledge about the adverse effects of SSB intake is significantly associated with SSB intake among adults suggests that health education regarding the potential contribution of excess energy intake from SSBs to weight gain could contribute to lowered consumption and lower rates of obesity. Although knowledge about the kilocalorie content of regular soda was unrelated to SSB intake, health education on the kilocalorie content of SSBs may still be beneficial because most adults did not know the actual kilocalorie content of SSBs. Longitudinal studies are needed to explore associations between knowledge about energy provided by SSBs and SSB intake. Published by Elsevier Inc.

The Relationship between Health-Related Knowledge and Sugar-Sweetened Beverage Intake among US Adults

PubMed Central

Park, Sohyun; Onufrak, Stephen; Sherry, Bettylou; Blanck, Heidi M.

2015-01-01

Because there is limited information on associations between health-related knowledge and sugar-sweetened beverage (SSB) intake, our cross-sectional study examined this question using the 2010 HealthStyles Survey data for 3,926 adults (aged ≥18 years). Multivariable logistic regression analysis was used to estimate the adjusted odds ratios and 95% CIs for drinking SSBs ≥2 times per day. About 31% of adults consumed SSBs ≥1 time per day, with 20% doing so ≥2 times per day. About eight of 10 adults agreed that drinking SSBs can contribute to weight gain, yet, eight of 10 adults in this study did not know the actual kilocalorie content of a 24-oz fountain soda. After controlling for age, sex, race/ethnicity, education level, annual household income, and geographic region, the odds for drinking SSBs ≥2 times per day were significantly higher among adults who neither agreed nor disagreed (ie, were neutral) that drinking SSBs can contribute to weight gain (odds ratio 1.61, 95% CI 1.15 to 2.25 vs agree); however, knowledge about the energy content of regular soda was not associated with SSB intake. Our finding that knowledge about the adverse effects of SSB intake is significantly associated with SSB intake among adults suggests that health education regarding the potential contribution of excess energy intake from SSBs to weight gain could contribute to lowered consumption and lower rates of obesity. Although knowledge about the kilocalorie content of regular soda was unrelated to SSB intake, health education on the kilocalorie content of SSBs may still be beneficial because most adults did not know the actual kilocalorie content of SSBs. Longitudinal studies are needed to explore associations between knowledge about energy provided by SSBs and SSB intake. PMID:24360502

Association Between Consumption of Sugar-Sweetened Beverages and Sociodemographic Characteristics Among Mississippi Adults

PubMed Central

Vargas, Rodolfo; Payton, Marinelle; Cannon-Smith, Gerri

2017-01-01

Introduction The consumption of sugar-sweetened beverages (SSBs) is linked to excessive weight gain, diabetes, and risk of cardiovascular disease. We examined the association between SSB consumption and sociodemographic characteristics among Mississippi adults. Methods We used data from the 2012 Mississippi Behavioral Risk Factor Surveillance System, which collected information on SSB consumption from 7,485 respondents. We used logistic regression models to calculate adjusted prevalence ratios (APRs) and 95% confidence intervals (CIs) for characteristics associated with SSB consumption. Results In 2012, 40.8% of Mississippi adults reported consuming at least one SSB daily. The likelihood of consuming SSBs at least once daily among respondents aged 18 to 34 years was 2.81 times higher (APR, 2.81; 95% CI, 2.49–3.18) than among those aged 65 years or older. The prevalence among men was 20% higher (APR, 1.20; 95% CI, 1.11–1.30) than among women and 23% higher (APR, 1.23; 95% CI, 1.13–1.35) among black respondents than among white respondents. The prevalence among respondents with less than a high school education was 25% higher (APR, 1.25; 95% CI, 1.11–1.41) than among those who with more than a high school education and 33% higher (APR, 1.33; 95% CI, 1.16–1.52) among those with an annual household income of less than $20,000 than among those with an income of $50,000 or more. Conclusion Among Mississippi adults, age, sex, race, education level, and income are associated with an increased likelihood of SSB consumption. Findings highlight the need for policies and interventions to address SSB consumption and promote alternatives to SSBs among Mississippians. PMID:29267157

Predicting Dietary Intake among Children Classified as Overweight or at Risk for Overweight: Independent and Interactive Effects of Parenting Practices and Styles

PubMed Central

Langer, Shelby L.; Seburg, Elisabeth; JaKa, Meghan M.; Sherwood, Nancy E.; Levy, Rona L.

2017-01-01

Using baseline data from a randomized controlled pediatric obesity prevention trial, this study sought to examine general parenting style as a potential moderator of the association between feeding-specific parenting practices and child dietary intake. Four hundred and twenty-one parent-child dyads served as participants (49% girls and 93% mothers). Children were, on average, 6.6 years old and either overweight or at-risk for overweight (mean BMI percentile = 84.9). Data were collected in participants’ homes. Study staff measured children’s height and weight. Parents completed questionnaires designed to assess general parenting styles (authoritative, authoritarian and permissive) and child feeding practices (restriction and monitoring). Child dietary intake was assessed using a 24-hour recall system. Outcomes were daily servings of fruits and vegetables, sugar-sweetened beverages (SSB), and unhealthy snacks. Results were as follows: Permissive parenting was inversely associated with fruit and vegetable consumption, and parental monitoring was inversely associated with SSB consumption. There were no other main effects of parenting style or feeding practice on child dietary consumption. Authoritarian parenting moderated the association between restriction and SSB intake (a marginally significant effect after correcting for multiple comparisons). Restriction was inversely associated with SSB consumption when authoritarianism was high but unassociated with SSB consumption when authoritarianism was low. Findings indicate that the parenting practice of monitoring child dietary intake was associated with more healthful consumption regardless of parenting style; interventions may thus benefit from encouraging parental monitoring. The parenting strategy of restricting child dietary intake, in contrast, was associated with lower SSB intake in the context of higher parental authoritarianism but inconsequential in the context of lower parental authoritarianism. This exploratory finding warrants further investigation. PMID:27940314

Predicting dietary intake among children classified as overweight or at risk for overweight: Independent and interactive effects of parenting practices and styles.

PubMed

Langer, Shelby L; Seburg, Elisabeth; JaKa, Meghan M; Sherwood, Nancy E; Levy, Rona L

2017-03-01

Using baseline data from a randomized controlled pediatric obesity prevention trial, this study sought to examine general parenting style as a potential moderator of the association between feeding-specific parenting practices and child dietary intake. Four hundred and twenty-one parent-child dyads served as participants (49% girls and 93% mothers). Children were, on average, 6.6 years old and either overweight or at-risk for overweight (mean BMI percentile = 84.9). Data were collected in participants' homes. Study staff measured children's height and weight. Parents completed questionnaires designed to assess general parenting styles (authoritative, authoritarian and permissive) and child feeding practices (restriction and monitoring). Child dietary intake was assessed using a 24-h recall system. Outcomes were daily servings of fruits and vegetables, sugar-sweetened beverages (SSB), and unhealthy snacks. Results were as follows: Permissive parenting was inversely associated with fruit and vegetable consumption, and parental monitoring was inversely associated with SSB consumption. There were no other main effects of parenting style or feeding practice on child dietary consumption. Authoritarian parenting moderated the association between restriction and SSB intake (a marginally significant effect after correcting for multiple comparisons). Restriction was inversely associated with SSB consumption when authoritarianism was high but unassociated with SSB consumption when authoritarianism was low. Findings indicate that the parenting practice of monitoring child dietary intake was associated with more healthful consumption regardless of parenting style; interventions may thus benefit from encouraging parental monitoring. The parenting strategy of restricting child dietary intake, in contrast, was associated with lower SSB intake in the context of higher parental authoritarianism but inconsequential in the context of lower parental authoritarianism. This exploratory finding warrants further investigation. Copyright © 2016 Elsevier Ltd. All rights reserved.

Familial and individual predictors of obesity and insulin resistance in urban Hispanic children

PubMed Central

Santiago-Torres, Margarita; Cui, Yuchen; Adams, Alexandra K.; Allen, David B.; Carrel, Aaron L.; Guo, Jessica Y.; Delgado-Rendon, Angelica; LaRowe, Tara L.; Schoeller, Dale A.

2015-01-01

Background High intake of sugar-sweetened beverages (SSB) has been suggested to contribute to the pediatric obesity epidemic, however, how the home food environment influence children’s intake of SSB among Hispanic families is still poorly understood. Objectives To evaluate the relationships between the home food environment and Hispanic children’s diet in relation to weight status and insulin resistance (IR). Methods A food frequency questionnaire was administered to 187 Hispanic children (ages 10 to 14 years), and anthropometrics were measured. IR was estimated from fasting insulin and glucose levels using the homeostasis model assessment of insulin resistance (HOMAIR). Parents reported on family demographics and the home food environment. A structural equation modeling approach was applied to examine the hypothesized relationships among variables. Results The prevalence of childhood overweight and obesity was 52.8% and it was positively associated with HOMAIR (β=0.687, P <.0001). Children’s SSB consumption was positively associated with children’s BMI z-score (β=0.151, P <0.05) and subsequently to HOMAIR. Children’s SSB consumption was predicted by home availability (β=0.191) and parental intake of SSB (β=0.419) (P <0.05). The model fit indices [X2 = 45.821 (d.f. = 30, P > 0.01 and < 0.05), X2/d.f. = 1.53, RMSEA = 0.053 (90% C.I. = 0.016, 0.082), CFI = 0.904] suggested a satisfactory goodness-of-fit. Conclusions The home food environment and parental diet seem to play an important role in the children’s access to and intake of SSB, which in turn predicted children’s weight status. PMID:25728238

Serum Carbon Isotope Values Change in Adults in Response to Changes in Sugar-Sweetened Beverage Intake12

PubMed Central

Fakhouri, Tala H. I.; Jahren, A. Hope; Appel, Lawrence J.; Chen, Liwei; Alavi, Reza; Anderson, Cheryl A. M.

2014-01-01

Serum carbon isotope values [13C-to-12C serum carbon isotope ratio (δ13C)], which reflect consumption of corn- and cane-based foods, differ between persons consuming high and low amounts of sugar-sweetened beverages (SSBs). In this study, we determined whether serum δ13C changes in response to change in SSB intake during an 18-mo behavioral intervention trial. Data were from a subset of 144 participants from the PREMIER trial, a completed behavioral intervention (Maryland, 1998–2004). SSB intake was assessed using 2 24-h dietary recall interviews. Blinded serum samples were assayed for δ13C by natural abundance stable isotope mass spectroscopy. Multiple linear regression models with generalized estimating equations and robust variance estimation were used. At baseline, mean SSB intake was 13.8 ± 14.2 fl oz/d, and mean δ13C serum value was −19.3 ± 0.6 units per mil (designated ‰). A reduction of 12 oz (355 mL)/d SSB (equivalent to 1 can of soda per day) was associated with 0.17‰ (95% CI: 0.08‰, 0.25‰ P < 0.0001) reduction in serum δ13C values over 18 mo (equivalent to a 1% reduction in δ13C from baseline). After adjusting for potential confounders, a reduction of 12 oz/d SSB (equivalent to 1 can of soda per day), over an 18-mo period, was associated with 0.12‰ (95% CI: 0.01‰, 0.22‰ P = 0.025) reduction in serum δ13C. These findings suggest that serum δ13C can be used as a measure of dietary changes in SSB intake. PMID:24717368

Prevalence and duration of social security benefits allowed to workers with asthma in Brazil in 2008.

PubMed

Branco, Anadergh Barbosa de Abreu; Ildefonso, Simone de Andrade Goulart

2012-01-01

To determine the prevalence and duration of social security benefits (SSBs) claims to registered workers with asthma in Brazil by the Brazilian National Institute of Social Security in 2008. This was a retrospective, descriptive study, based on information obtained from the Brazilian Unified Benefit System database, on the number of SSB claims granted to registered workers with asthma in 2008. The reference population was the monthly mean number of workers registered in the Brazilian Social Registry Database in 2008. The variables studied were type of economic activity, gender, age, and type/duration of the SSB claim. The relationship between work and asthma was evaluated by the prevalence ratio (PR) between work-related and non-work-related SSB claims for asthma. In 2008, 2,483 SSB claims were granted for asthma, with a prevalence of 7.5 allowances per 100,000 registered workers. The prevalence was higher among females than among males (PR = 2.1 between the sexes). Workers > 40 years of age were 2.5 times more likely to be granted an SSB claim for asthma than were younger workers. The prevalence was highest among workers engaged in the following types of economic activity: sewage, wood and wood product manufacturing, and furniture manufacturing (78.8, 22.4, and 22.2 claims/100,000 registered workers, respectively). The median (interquartile range) duration of SSB claims for asthma was 49 (28-87) days. Asthma is a major cause of sick leave, and its etiology has a strong occupational component. This has a major impact on employers, employees, and the social security system. Being female, being > 40 years of age, and working in the areas of urban sanitation/sewage, wood and wood product manufacturing, and furniture manufacturing increase the chance of sick leave due to asthma.

[Soil seed bank research in China: present status, progress and challenges].

PubMed

Shen, You-Xin; Zhao, Chun-Yan

2009-02-01

By searching soil seed bank (SSB) papers from http://www.cqvip.com (1989-2006) and Web of Science (1985-2006), the information on SSB density, species richness, and research methods were summarized according to the 29 classified vegetation types in Vegetation of China. In total, the data of 238 sites with 14 vegetation types were collected. The results showed that the research methods adopted by different researchers and the obtained data of SSB density and species richness varied greatly. In related researches, sampling work was mostly conducted in April and October, sampling plot number ranged from 2 to 480, plot area ranged from 78 cm2 to 10,000 cm2, with 10 cm x 10 cm and 20 cm x 20 cm as most common, and total sampling area ranged from 600 cm2 to 500,000 cm2, with the most being 1,000-10,000 cm2. SSB density varied from 8 ind x m(-2) (desert) to 65,355 ind x m(-2) (tropical rain forest), and species richness varied from 1 (secondary bare alkali-saline patch in temperate) to 74 (tropical seasonal rain forest) per site. SSB density and species richness were higher in tropical rain forest and seasonal rain forest than in temperate coniferous forest, and in manmade forest than in agricultural land or barren land. Grassland, desert, and meadow had smaller species richness. In future, the SSB research should be extended both in scope and in deepness, with the focus on the long term research and strategy research of some important ecosystems, and the research should be incorporated into vegetation regeneration and restoration studies. The related methodological research should be also emphasized in the future.

A systematic approach to evaluate parameter consistency in the inlet stream of source separated biowaste composting facilities: A case study in Colombia.

PubMed

Oviedo-Ocaña, E R; Torres-Lozada, P; Marmolejo-Rebellon, L F; Torres-López, W A; Dominguez, I; Komilis, D; Sánchez, A

2017-04-01

Biowaste is commonly the largest fraction of municipal solid waste (MSW) in developing countries. Although composting is an effective method to treat source separated biowaste (SSB), there are certain limitations in terms of operation, partly due to insufficient control to the variability of SSB quality, which affects process kinetics and product quality. This study assesses the variability of the SSB physicochemical quality in a composting facility located in a small town of Colombia, in which SSB collection was performed twice a week. Likewise, the influence of the SSB physicochemical variability on the variability of compost parameters was assessed. Parametric and non-parametric tests (i.e. Student's t-test and the Mann-Whitney test) showed no significant differences in the quality parameters of SSB among collection days, and therefore, it was unnecessary to establish specific operation and maintenance regulations for each collection day. Significant variability was found in eight of the twelve quality parameters analyzed in the inlet stream, with corresponding coefficients of variation (CV) higher than 23%. The CVs for the eight parameters analyzed in the final compost (i.e. pH, moisture, total organic carbon, total nitrogen, C/N ratio, total phosphorus, total potassium and ash) ranged from 9.6% to 49.4%, with significant variations in five of those parameters (CV>20%). The above indicate that variability in the inlet stream can affect the variability of the end-product. Results suggest the need to consider variability of the inlet stream in the performance of composting facilities to achieve a compost of consistent quality. Copyright © 2017 Elsevier Ltd. All rights reserved.

African-American and Hispanic Children’s Beverage Intake: Differences in Associations with Desire to Drink, Fathers’ Feeding Practices, and Weight Concerns

PubMed Central

Lora, Karina R.; Hubbs-Tait, Laura; Ferris, Ann M.; Wakefield, Dorothy

2016-01-01

Relationships of African-American and Hispanic fathers’ feeding practices and weight concerns and preschoolers’ desire to drink with children’s beverage intake were examined, and associations between fathers’ feeding practices and children’s weight status were evaluated. Fathers’ (Hispanic n = 61, African-American n = 49) difficulty in child feeding, use of food to calm, use of food as reward, and concern about the child being under and overweight as well as their child’s desire to drink were assessed. Preschoolers’ (ages 2 to 5) total sugar-sweetened beverage (SSB), fruit juice, and water intake were measured by a modified beverage intake questionnaire. Body Mass Index (BMI) and BMI percentile were calculated for fathers and children, respectively. Multiple regressions revealed that, in Hispanics, difficulty in feeding, concern about underweight, use of food to calm, and use of food as a reward were significantly associated with child intake of total SSB, whereas, in African-Americans, child desire to drink was associated with total SSB and fruit juice. Concern about the child being underweight was inversely associated with child BMI percentile in Hispanics. Significant differences in regression coefficients of child SSB intake to fathers’ behaviors versus child desire to drink between the two racial-ethnic groups indicated that use of food to calm the child predicted increased intake of SSB by Hispanic but not by African-American children, while child desire to drink predicted increased intake of SSB by African-American but not by Hispanic children. Because of these significant differences, future research might profitably explore socio-cultural influences on associations of additional child feeding behaviors with fathers’ attempts to control them. Furthermore, practitioners should consider developing and evaluating different child obesity interventions for these two racial-ethnic groups. PMID:27620644

Contemporary management issues confronting fisheries science

NASA Astrophysics Data System (ADS)

Frank, Kenneth T.; Brickman, David

2001-06-01

Stock collapses have occurred worldwide. The most frequently cited cause is over-fishing, suggesting that fisheries management has been ineffective in controlling exploitation rates. The progression of a fishery from an over-exploited to a collapsed state involves impairment of the reproductive capacity of the target species, i.e. recruitment over-fishing. In many cases, this occurs by reduction of the spawning stock biomass (SSB) through the systematic elimination of spawning components within a stock complex. While operational definitions of minimum levels of SSB have been developed, they have seldom been applied and never adopted in a Canadian groundfish management context. The answer to the question of how much is enough to perpetuate a stock under exploitation has been illusive. Serebryakov [J. Cons. Int. Explor. Mer, 47 (1990) 267] has advocated definition of critical levels of SSB based on survival rates (R/SSB). We review his method and discuss the utility of the approach. An alternative approach to the problem of estimating minimum SSB is through a fundamental revision of the traditional stock and recruitment relationship. Explicit theoretical SSB thresholds below which reproduction/recruitment is severely impaired based upon density-dependent mating success (or Allee effects) is considered a superior approach to the question of how much is enough because of its ecological grounding. However, the successful application of this approach will require re-definition of the space/time scales of the management unit. Finally, support is growing for the establishment of closed areas or "no-take zones" as an alternative approach to managing the problems of fishing a stock complex by enabling sub-populations to escape fishing. While the expected benefits of areas protected from fishing are numerous, clear demonstrations of benefits of such areas in marine temperate ecosystems are lacking. In fact, unintended negative consequences may result from such actions.

Serum carbon isotope values change in adults in response to changes in sugar-sweetened beverage intake.

PubMed

Fakhouri, Tala H I; Jahren, A Hope; Appel, Lawrence J; Chen, Liwei; Alavi, Reza; Anderson, Cheryl A M

2014-06-01

Serum carbon isotope values [13C-to-12C serum carbon isotope ratio (δ(13)C)], which reflect consumption of corn- and cane-based foods, differ between persons consuming high and low amounts of sugar-sweetened beverages (SSBs). In this study, we determined whether serum δ(13)C changes in response to change in SSB intake during an 18-mo behavioral intervention trial. Data were from a subset of 144 participants from the PREMIER trial, a completed behavioral intervention (Maryland, 1998-2004). SSB intake was assessed using 2 24-h dietary recall interviews. Blinded serum samples were assayed for δ(13)C by natural abundance stable isotope mass spectroscopy. Multiple linear regression models with generalized estimating equations and robust variance estimation were used. At baseline, mean SSB intake was 13.8 ± 14.2 fl oz/d, and mean δ(13)C serum value was -19.3 ± 0.6 units per mil (designated ‰). A reduction of 12 oz (355 mL)/d SSB (equivalent to 1 can of soda per day) was associated with 0.17‰ (95% CI: 0.08‰, 0.25‰ P < 0.0001) reduction in serum δ(13)C values over 18 mo (equivalent to a 1% reduction in δ(13)C from baseline). After adjusting for potential confounders, a reduction of 12 oz/d SSB (equivalent to 1 can of soda per day), over an 18-mo period, was associated with 0.12‰ (95% CI: 0.01‰, 0.22‰ P = 0.025) reduction in serum δ(13)C. These findings suggest that serum δ(13)C can be used as a measure of dietary changes in SSB intake. © 2014 American Society for Nutrition.

Observational demonstration of a high image rejection SIS mixer receiver using a new waveguide filter at 230 GHz

NASA Astrophysics Data System (ADS)

Hasegawa, Yutaka; Asayama, Shinichiro; Harada, Ryohei; Tokuda, Kazuki; Kimura, Kimihiro; Ogawa, Hideo; Onishi, Toshikazu

2017-12-01

A new sideband separation method was developed for use in millimeter-/submillimeter-band radio receivers using a novel waveguide frequency separation filter (FSF), which consists of two branch line hybrid couplers and two waveguide high-pass filters. The FSF was designed to allow the radio frequency (RF) signal to pass through to an output port when the frequency is higher than a certain value (225 GHz), and to reflect the RF signal back to another output port when the frequency is lower. The FSF is connected to two double sideband superconductor-insulator-superconductor (SIS) mixers, and an image rejection ratio (IRR) is determined by the FSF characteristics. With this new sideband separation method, we can achieve good and stable IRR without the balancing two SIS mixers such as is necessary for conventional sideband-separating SIS mixers. To demonstrate the applicability of this method, we designed and developed an FSF for simultaneous observations of the J = 2-1 rotational transition lines of three CO isotopes (12CO, 13CO, and C18O): the 12CO line is in the upper sideband and the others are in the lower sideband with an intermediate-frequency range of 4-8 GHz at the radio frequency of 220/230 GHz. This FSF was then installed in the receiver system of the 1.85 m radio telescope of Osaka Prefecture University, and was used during the 2014 observation season. The observation results indicate that the IRR of the proposed receiver is 25 dB or higher for the 12CO line, and no significant fluctuation larger than 1 dB in the IRR was observed throughout the season. These results demonstrate the practical utility of the FSF receiver for observations like extensive molecular cloud surveys in specified lines with a fixed frequency setting.

Evidence-based mapping of design heterogeneity prior to meta-analysis: a systematic review and evidence synthesis.

PubMed

Althuis, Michelle D; Weed, Douglas L; Frankenfeld, Cara L

2014-07-23

Assessment of design heterogeneity conducted prior to meta-analysis is infrequently reported; it is often presented post hoc to explain statistical heterogeneity. However, design heterogeneity determines the mix of included studies and how they are analyzed in a meta-analysis, which in turn can importantly influence the results. The goal of this work is to introduce ways to improve the assessment and reporting of design heterogeneity prior to statistical summarization of epidemiologic studies. In this paper, we use an assessment of sugar-sweetened beverages (SSB) and type 2 diabetes (T2D) as an example to show how a technique called 'evidence mapping' can be used to organize studies and evaluate design heterogeneity prior to meta-analysis.. Employing a systematic and reproducible approach, we evaluated the following elements across 11 selected cohort studies: variation in definitions of SSB, T2D, and co-variables, design features and population characteristics associated with specific definitions of SSB, and diversity in modeling strategies. Evidence mapping strategies effectively organized complex data and clearly depicted design heterogeneity. For example, across 11 studies of SSB and T2D, 7 measured diet only once (with 7 to 16 years of disease follow-up), 5 included primarily low SSB consumers, and 3 defined the study variable (SSB) as consumption of either sugar or artificially-sweetened beverages. This exercise also identified diversity in analysis strategies, such as adjustment for 11 to 17 co-variables and a large degree of fluctuation in SSB-T2D risk estimates depending on variables selected for multivariable models (2 to 95% change in the risk estimate from the age-adjusted model). Meta-analysis seeks to understand heterogeneity in addition to computing a summary risk estimate. This strategy effectively documents design heterogeneity, thus improving the practice of meta-analysis by aiding in: 1) protocol and analysis planning, 2) transparent reporting of differences in study designs, and 3) interpretation of pooled estimates. We recommend expanding the practice of meta-analysis reporting to include a table that summarizes design heterogeneity. This would provide readers with more evidence to interpret the summary risk estimates.

Evidence-based mapping of design heterogeneity prior to meta-analysis: a systematic review and evidence synthesis

PubMed Central

2014-01-01

Background Assessment of design heterogeneity conducted prior to meta-analysis is infrequently reported; it is often presented post hoc to explain statistical heterogeneity. However, design heterogeneity determines the mix of included studies and how they are analyzed in a meta-analysis, which in turn can importantly influence the results. The goal of this work is to introduce ways to improve the assessment and reporting of design heterogeneity prior to statistical summarization of epidemiologic studies. Methods In this paper, we use an assessment of sugar-sweetened beverages (SSB) and type 2 diabetes (T2D) as an example to show how a technique called ‘evidence mapping’ can be used to organize studies and evaluate design heterogeneity prior to meta-analysis.. Employing a systematic and reproducible approach, we evaluated the following elements across 11 selected cohort studies: variation in definitions of SSB, T2D, and co-variables, design features and population characteristics associated with specific definitions of SSB, and diversity in modeling strategies. Results Evidence mapping strategies effectively organized complex data and clearly depicted design heterogeneity. For example, across 11 studies of SSB and T2D, 7 measured diet only once (with 7 to 16 years of disease follow-up), 5 included primarily low SSB consumers, and 3 defined the study variable (SSB) as consumption of either sugar or artificially-sweetened beverages. This exercise also identified diversity in analysis strategies, such as adjustment for 11 to 17 co-variables and a large degree of fluctuation in SSB-T2D risk estimates depending on variables selected for multivariable models (2 to 95% change in the risk estimate from the age-adjusted model). Conclusions Meta-analysis seeks to understand heterogeneity in addition to computing a summary risk estimate. This strategy effectively documents design heterogeneity, thus improving the practice of meta-analysis by aiding in: 1) protocol and analysis planning, 2) transparent reporting of differences in study designs, and 3) interpretation of pooled estimates. We recommend expanding the practice of meta-analysis reporting to include a table that summarizes design heterogeneity. This would provide readers with more evidence to interpret the summary risk estimates. PMID:25055879

Determinants of Sugar-Sweetened Beverage Consumption among Low-Income Children: Are There Differences by Race/Ethnicity, Age, and Sex?

PubMed

Tasevska, Natasha; DeLia, Derek; Lorts, Cori; Yedidia, Michael; Ohri-Vachaspati, Punam

2017-12-01

Understanding determinants of high consumption of sugar-sweetened beverages (SSBs), a highly prevalent obesogenic behavior, will help build effective customized public health interventions. Our aim was to identify child and parent lifestyle and household demographic factors predictive of high SSB consumption frequency in children from low-income, ethnically diverse communities that may help inform public health interventions. We used a cross-sectional telephone household survey. Participants were 717 boys and 686 girls aged 3 to 18 years old from the New Jersey Childhood Obesity Study living in five low-income cities (Camden, New Brunswick, Newark, Trenton, and Vineland). The adult most knowledgeable about household food shopping completed a questionnaire over the telephone inquiring about their and their child's dietary and physical activity habits, and household-, parent-, and child-level demographics. Child's SSB consumption frequency was measured. Multivariate ordered logit models were designed to investigate a variety of variables hypothesized to affect the frequency of SSB consumption. Exploratory stratified analyses by race, sex, and age were also conducted. Eight percent of our study participants never consumed SSBs, 45% consumed SSBs at least once per day, and 23% consumed twice or more per day. SSB consumption was higher among children 12 to 18 years vs 3 to 5 years (P<0.0001), of non-Hispanic black vs non-Hispanic white race/ethnicity (P=0.010), who were moderate fast food consumers vs never consumers (P=0.003), and those whose parents were high vs low SSB consumers (P<0.0001). Living in a non-English-speaking household (P=0.030), having a parent with a college or higher education vs less than high school (P=0.003), and having breakfast 6 to 7 days/wk vs never to 2 days/wk or less were associated with lower SSB consumption (P=0.001). We identified a number of household-, parent-, and child-level predictors of SSB consumption, which varied by race, sex, and age, useful for building customized interventions targeting certain behaviors in ethnically diverse, low-income children. Copyright © 2017 Academy of Nutrition and Dietetics. Published by Elsevier Inc. All rights reserved.

A systematic review investigating interventions that can help reduce consumption of sugar-sweetened beverages in children leading to changes in body fatness.

PubMed

Avery, A; Bostock, L; McCullough, F

2015-01-01

Both the prevalence of childhood obesity and the consumption of sugar-sweetened beverages (SSBs) have increased globally. The present review describes interventions that reduce the consumption of SSBs in children and determines whether this leads to subsequent changes in body fatness. Three databases were searched from 2000 to August 2013. Only intervention control trials, ≥6 months in duration, which aimed to reduce the consumption of SSBs in >100 children aged 2-18 years, and reporting changes in body fatness, were included. The quality of selected papers was assessed. Eight studies met inclusion criteria. Six interventions achieved significant (P < 0.05) reductions in SSB intake, although this was not always sustained. In the two interventions providing replacement drinks, significant differences in body mass index (12- or 18-month follow-up) were reported (P = 0.001 and 0.045). The risk of being overweight/obesity was reduced (P < 0.05) in three of the five education programmes but in one programme only for girls who were overweight at baseline and in one programme only for pupils perceived to be at greater risk at baseline. In the one study that included both provision of water and education, the risk of being overweight was reduced by 31% (P = 0.04) in the intervention group. The evidence suggests that school-based education programmes focusing on reducing SSB consumption, but including follow-up modules, offer opportunities for implementing effective, sustainable interventions. Peer support and changing the school environment (e.g. providing water or replacement drinks) to support educational programmes could improve their effectiveness. Home delivery of more suitable drinks has a big impact on reducing SSB consumption, with associated reductions in body weight. © 2014 The Authors. Journal of Human Nutrition and Dietetics published by John Wiley & Sons Ltd on behalf of British Dietetic Association.

A systematic review investigating interventions that can help reduce consumption of sugar-sweetened beverages in children leading to changes in body fatness

PubMed Central

Avery, A; Bostock, L; McCullough, F

2015-01-01

Background Both the prevalence of childhood obesity and the consumption of sugar-sweetened beverages (SSBs) have increased globally. The present review describes interventions that reduce the consumption of SSBs in children and determines whether this leads to subsequent changes in body fatness. Methods Three databases were searched from 2000 to August 2013. Only intervention control trials, ≥6 months in duration, which aimed to reduce the consumption of SSBs in >100 children aged 2–18 years, and reporting changes in body fatness, were included. The quality of selected papers was assessed. Results Eight studies met inclusion criteria. Six interventions achieved significant (P < 0.05) reductions in SSB intake, although this was not always sustained. In the two interventions providing replacement drinks, significant differences in body mass index (12- or 18-month follow-up) were reported (P = 0.001 and 0.045). The risk of being overweight/obesity was reduced (P < 0.05) in three of the five education programmes but in one programme only for girls who were overweight at baseline and in one programme only for pupils perceived to be at greater risk at baseline. In the one study that included both provision of water and education, the risk of being overweight was reduced by 31% (P = 0.04) in the intervention group. Conclusions The evidence suggests that school-based education programmes focusing on reducing SSB consumption, but including follow-up modules, offer opportunities for implementing effective, sustainable interventions. Peer support and changing the school environment (e.g. providing water or replacement drinks) to support educational programmes could improve their effectiveness. Home delivery of more suitable drinks has a big impact on reducing SSB consumption, with associated reductions in body weight. PMID:25233843

Modulation of DNA repair capacity and mRNA expression levels of XRCC1, hOGG1 and XPC genes in styrene-exposed workers.

PubMed

Hanova, Monika; Stetina, Rudolf; Vodickova, Ludmila; Vaclavikova, Radka; Hlavac, Pavel; Smerhovsky, Zdenek; Naccarati, Alessio; Polakova, Veronika; Soucek, Pavel; Kuricova, Miroslava; Manini, Paola; Kumar, Rajiv; Hemminki, Kari; Vodicka, Pavel

2010-11-01

Decreased levels of single-strand breaks in DNA (SSBs), reflecting DNA damage, have previously been observed with increased styrene exposure in contrast to a dose-dependent increase in the base-excision repair capacity. To clarify further the above aspects, we have investigated the associations between SSBs, micronuclei, DNA repair capacity and mRNA expression in XRCC1, hOGG1 and XPC genes on 71 styrene-exposed and 51 control individuals. Styrene concentrations at workplace and in blood characterized occupational exposure. The workers were divided into low (below 50 mg/m³) and high (above 50 mg/m³)) styrene exposure groups. DNA damage and DNA repair capacity were analyzed in peripheral blood lymphocytes by Comet assay. The mRNA expression levels were determined by qPCR. A significant negative correlation was observed between SSBs and styrene concentration at workplace (R=-0.38, p=0.001); SSBs were also significantly higher in men (p=0.001). The capacity to repair irradiation-induced DNA damage was the highest in the low exposure group (1.34±1.00 SSB/10⁹ Da), followed by high exposure group (0.72±0.81 SSB/10⁹ Da) and controls (0.65±0.82 SSB/10⁹ Da). The mRNA expression levels of XRCC1, hOGG1 and XPC negatively correlated with styrene concentrations in blood and at workplace (p<0.001) and positively with SSBs (p<0.001). Micronuclei were not affected by styrene exposure, but were higher in older persons and in women (p<0.001). In this study, we did not confirm previous findings on an increased DNA repair response to styrene-induced genotoxicity. However, negative correlations of SSBs and mRNA expression levels of XRCC1, hOGG1 and XPC with styrene exposure warrant further highly-targeted study. Copyright © 2010 Elsevier Inc. All rights reserved.