bluuebunny/crossref_metadata_2025 huggingface dataset:
The Baby-Friendly Hospital Initiative in Switzerland
Authors: Forrester-Knauss Christine , Merten Sonja , Weiss Carine , Ackermann-Liebrich Ursula , Zemp Stutz Elisabeth
Published: April 2013

Background:

This article reports the trends over a 9-year period for 4 steps of the Baby-Friendly Hospital Initiative (BFHI) (exclusive breastfeeding, uninterrupted rooming-in, no use of pacifiers, and initiation of breastfeeding within the first 2 hours after birth) during hospital stays in Switzerland.

Methods:

Data were collected annually over a period of 9 years from a monitoring survey of all BFHI-accredited hospitals in Switzerland (between 41 and 65 hospitals). The number of participants included in the study per year ranged between 15 627 and 31 141 healthy mother–newborn pairs.

Results:

Significant improvements were found for 3 of the 4 steps of the BFHI between 2000 and 2008: rates of exclusive breastfeeding during postpartum stay (35.9%-57.6%, P < .001), uninterrupted rooming-in (48.2%-73.1%, P < .001), and no use of pacifiers (33.6%-48.1%, P < .001). Initiation of breastfeeding within the first 2 hours after birth was always > 90% and did not change significantly over the 9 years. Exclusive breastfeeding during hospital stay was significantly related to no use of pacifiers ( P < .001) and to uninterrupted rooming-in ( P < .001) in the years when exclusive breastfeeding particularly increased (2003, 2004, and 2008).

Conclusion:

Rates of exclusive breastfeeding during hospital stay and uninterrupted rooming-in increased significantly over the 9 years. Continued promotion of the BFHI may be needed to maintain or further improve the breastfeeding rates and to find ways to deal with difficulties that hospitals face when applying the 10 steps of the BFHI.
Triboluminescence for distributed damage assessment in cement-based materials
Authors: Aich Nirupam , Appalla Aditya , Saleh Navid B , Ziehl Paul
Published: April 2013

Triboluminescent materials are promising in the field of structural health monitoring for real-time crack detection and related damage assessment. This study presents a simple, but novel, image processing protocol to detect and quantify luminescence from crack formation in cement-based matrices. Mortar cubes of 2″× 2″ (5.1 cm × 5.1 cm) were loaded in compression with an external coating of manganese-doped zinc sulfide (ZnS:Mn) triboluminescent material. The concentration of triboluminescent material and rate of loading were varied to evaluate luminescence response. A digital single lens reflex camera was employed to capture luminescence from the resulting cracks, which formed and propagated during failure. The images were then analyzed with an image processor, and total luminescence/pixel along the cracks was quantified. Results show that overall luminescence increases with the increase in triboluminescent concentration as well as with the rate of loading. This article presents a novel method that can be applied to monitor crack formation in cement-based materials, providing reliable accuracy in luminescence quantification.
Microstructure and tensile behaviour of 15–24 wt-Mn TWIP steels
Authors: Ding S X , Chang C P , Tu J F , Yang K C
Published: April 2013

The present study examines the microstructure and tensile behaviour of twinning induced plasticity steel with different Mn contents. The results show that reducing the Mn content from 24 to 15 wt- is beneficial for the improvement of the tensile strength and fracture strain of the steels. The effect of Mn content on the microstructure and workhardening behaviour as well as the effect of strain rate on the microstructure and tensile behaviour is discussed.
MicroRNAs activate natural killer cells through Toll-like receptor signaling
Authors: He Shun , Chu Jianhong , Wu Lai-Chu , Mao Hsiaoyin , Peng Yong , Alvarez-Breckenridge Christopher A. , Hughes Tiffany , Wei Min , Zhang Jianying , Yuan Shunzong , Sandhu Sumeet , Vasu Sumithira , Benson Don M. , C. Hofmeister Craig , He Xiaoming , Ghoshal Kalpana , Devine Steven M. , Caligiuri Michael A. , Yu Jianhua
Published: April 2013

Key Points

miRNAs activate NK cells through a TLR–NF-κB signaling pathway and may have therapeutic applications in cancer.
Fluorescence in situ Hybridization method using Peptide Nucleic Acid probes for rapid detection of Lactobacillus and Gardnerella spp.
Authors: Machado António , Almeida Carina , Salgueiro Débora , Henriques Ana , Vaneechoutte Mario , Haesebrouck Freddy , Vieira Maria João , Rodrigues Ligia , Azevedo Nuno Filipe , Cerca Nuno
Published: April 2013

Background

Bacterial vaginosis (BV) is a common vaginal infection occurring in women of reproductive age. It is widely accepted that the microbial switch from normal microflora to BV is characterized by a decrease in vaginal colonization by Lactobacillus species together with an increase of Gardnerella vaginalis and other anaerobes. Our goal was to develop and optimize a novel Peptide Nucleic Acid (PNA) Fluorescence in situ Hybridization assay (PNA FISH) for the detection of Lactobacillus spp. and G. vaginalis in mixed samples.

Results

Therefore, we evaluated and validated two specific PNA probes by using 36 representative Lactobacillus strains, 22 representative G. vaginalis strains and 27 other taxonomically related or pathogenic bacterial strains commonly found in vaginal samples. The probes were also tested at different concentrations of G. vaginalis and Lactobacillus species in vitro, in the presence of a HeLa cell line. Specificity and sensitivity of the PNA probes were found to be 98.0% (95% confidence interval (CI), from 87.8 to 99.9%) and 100% (95% CI, from 88.0 to 100.0%), for Lactobacillus spp.; and 100% (95% CI, from 92.8 to 100%) and 100% (95% CI, from 81.5 to 100.0%) for G. vaginalis. Moreover, the probes were evaluated in mixed samples mimicking women with BV or normal vaginal microflora, demonstrating efficiency and applicability of our PNA FISH.

Conclusions

This quick method accurately detects Lactobacillus spp. and G. vaginalis species in mixed samples, thus enabling efficient evaluation of the two bacterial groups, most frequently encountered in the vagina.
Comparative proteomics study on liver mitochondria of primary biliary cirrhosis mouse model
Authors: Song Guang , Hu Chaojun , Zhu Huishan , Li Xi , Zhao Liying , Zhou Renfang , Zhang Xuan , Zhang Fengchun , Wu Lin , Li Yongzhe
Published: April 2013

Background

Primary biliary cirrhosis (PBC) is a liver specific chronic disease with unclear pathogenesis, especially for the early stage molecular events. The mitochondrion is a multi-functional organelle associated with various diseases including PBC. The purpose of this study was to discover the alterations in the mitochondria proteome using an early stage PBC mouse model for revealing the possible pathogenesis mechanisms in the early stages of PBC.

Methods

Mouse model of early stage of PBC was constructed by consecutive administration of poly I:C. Mitochondria of mouse models and controls were purified and comparative proteomics was performed by iTRAQ technology. Then, differentially expressed proteins were validated by western blotting.

Results

In total 354 proteins that satisfied the criteria for comparative proteomics study were identified. Of them, nine proteins were downregulated and 20 were up-regulated in liver mitochondria of PBC mouse model. Most differentially expressed proteins are associated with oxidation-reduction and lipid metabolism, and some are involved in the biosynthesis of steroid hormone and primary bile acid. Interestingly, four proteins (HCDH, CPT I, DECR, ECHDC2) involved in the fatty acid beta-oxidation were all upregulated.

Conclusions

iTRAQ is a powerful tool for comparative proteomics study of PBC mouse model and differentially expressed proteins in mitochondria proteome of PBC mouse model provide insights for the pathogenesis mechanism at early stage of PBC.
Synthesis and cytotoxic properties of novel (E)-3-benzylidene-7-methoxychroman-4-one derivatives
Authors: Noushini Saeedeh , Alipour Eskandar , Emami Saeed , Safavi Maliheh , Ardestani Sussan Kabudanian , Gohari Ahmad Reza , Shafiee Abbas , Foroumadi Alireza
Published: April 2013

Background and the purpose of the study

There has been increscent interest in the field of cancer chemotherapy by discovery and development of novel agents with high efficacy, low toxicity, and minimum side effects. In order to find new anticancer agents, we replaced the pyrazolone part of well-known cytotoxic agent SJ-172550 with 7-methoxychroman-4-one. Thus, a novel series of 3-benzylidene-4-chromanones were synthesized and tested in vitro against human cancer cell lines.

Methods

The title compounds were prepared by condensation of 7-methoxychroman-4-one with suitable aldehydes in appropriate alcohol in the presence of gaseous HCl. The antiproliferative activity of target compounds were evaluated against MDA-MB-231 (breast cancer), KB (nasopharyngeal epidermoid carcinoma) and SK-N-MC (human neuroblastoma) cell lines using MTT assay.

Results

Although the direct analog of SJ-172550 (compound5d) did not show any cytotoxic activity against tested cell lines, but 2-(2-chloro-6-methoxyphenoxy)acetic acid methyl ester analog5cshowed some activity against MDA-MB-231 and SK-N-MC cells. Further modification of compound5cresulted in the 3-chloro-4,5-dimethoxybenzylidene derivative5bwhich demonstrated better cytotoxic profile against all tested cell lines (IC50values = 7.56–25.04 μg/ml).

Conclusion

The results demonstrated that the cytotoxic activity of compound5bagainst MDA-MB-231 and SK-N-MC cells is more than etoposide. Therefore, compound5bprototype could be considered as novel cytotoxic agent for further developing new anticancer chemotherapeutics.
Comparative meta-RNA-seq of the vaginal microbiota and differential expression by Lactobacillus iners in health and dysbiosis
Authors: Macklaim Jean M , Fernandes Andrew D , Di Bella Julia M , Hammond Jo-Anne , Reid Gregor , Gloor Gregory B
Published: April 2013

Background

Bacterial vaginosis (BV), the most common vaginal condition of reproductive-aged women, is associated with a highly diverse and heterogeneous microbiota. Here we present a proof-of-principle analysis to uncover the function of the microbiota using meta-RNA-seq to uncover genes and pathways that potentially differentiate healthy vaginal microbial communities from those in the dysbiotic state of bacterial vaginosis (BV).

Results

The predominant organism, Lactobacillus iners, was present in both conditions and showed a differing expression profile in BV compared to healthy. Despite its minimal genome, L. iners differentially expressed over 10% of its gene complement. Notably, in a BV environment L. iners increased expression of a cholesterol-dependent cytolysin, and of mucin and glycerol transport and related metabolic enzymes. Genes belonging to a CRISPR system were greatly upregulated suggesting that bacteriophage influence the community. Reflective of L. iners, the bacterial community as a whole demonstrated a preference for glycogen and glycerol as carbon sources under BV conditions. The predicted end-products of metabolism under BV conditions include an abundance of succinate and other short-chain fatty-acids, while healthy conditions are predicted to largely contain lactic acid.

Conclusions

Our study underscores the importance of understanding the functional activity of the bacterial community in addition to characterizing the population structure when investigating the human microbiome.
Ephrin B1 maintains apical adhesion of neural progenitors
Authors: Arvanitis Dina N. , Béhar Annie , Tryoen-Tóth Petra , Bush Jeff O. , Jungas Thomas , Vitale Nicolas , Davy Alice
Published: April 2013

Apical neural progenitors are polarized cells for which the apical membrane is the site of cell-cell and cell-extracellular matrix adhesion events that are essential for maintaining the integrity of the developing neuroepithelium. Apical adhesion is important for several aspects of the nervous system development, including morphogenesis and neurogenesis, yet the mechanisms underlying its regulation remain poorly understood. Here, we show that ephrin B1, a cell surface protein that engages in cell signaling upon binding cognate Eph receptors, controls normal morphogenesis of the developing cortex. Efnb1-deficient embryos exhibit morphological alterations of the neuroepithelium that correlate with neural tube closure defects. Using loss-of-function experiments by ex vivo electroporation, we demonstrate that ephrin B1 is required in apical progenitors (APs) to maintain their apical adhesion. Mechanistically, we show that ephrin B1 controls cell-ECM adhesion by promoting apical localization of integrin β1 and we identify ADP-ribosylation factor 6 (Arf6) as an important effector of ephrin B1 reverse signaling in apical adhesion of APs. Our results provide evidence for an important role for ephrin B1 in maintaining the structural integrity of the developing cortex and highlight the importance of tightly controlling apical cell-ECM adhesion for neuroepithelial development.
Obstetric brachial plexus injury: expectations before and satisfaction three months after secondary surgery on the shoulder
Authors: Westin Britt , Hultgren Tomas , Von Koch Lena
Published: April 2013

Introduction

Children affected by obstetrical brachial plexus injury frequently have residual externalrotation weakness in the shoulder. Secondary surgical procedures are available for improvement. The aim ofthis study was to describe and compare children's and parents’ expectations, the importance of selectedarm/hand function, and performance of activities before and satisfaction after surgical correction of rotationdeformity in the shoulder.

Method

In the Department of Hand Surgery, Södersjukhuset Sweden, all patients ≥4-year-olds (n = 42)affected by obstetrical plexus injury who underwent secondary surgery to release rotation contracture of the shoulder were included in this study between November 2001 and May 2006. A disease-specific questionnaire was developed and used.

Results

The expectations before surgery were that the majority of the activities and functions would be improved. There were some differences between the adolescents’ and their parents’ expectations. After surgery, both children and parents were overall satisfied.

Conclusion

This study shows that expectations before surgery were high and both children and parents reported positive experiences three months after surgery. A longterm study is warranted if final conclusions are to be drawn.
Algorithms for Time-Varying Networks of Many-Server Fluid Queues
Authors: Liu Yunan , Whitt Ward
Published: April 2013

Motivated by large-scale service systems with network structure, we introduced in a previous paper a time-varying open network of many-server fluid queues with customer abandonment from each queue and time-varying proportional routing among the queues, and showed how performance functions can be determined. The deterministic fluid model serves as an approximation for the corresponding non-Markovian stochastic network of many-server queues with Markovian routing, experiencing periods of overloading at the queues. In this paper we develop a new algorithm for the previous model and generalize the model to include non-exponential service-time distributions. In this paper we report results of implementing the algorithms and studying their computational complexity. We also conduct simulation experiments to confirm that the algorithms are effective in computing the performance functions and that these performance functions provide useful approximations for the corresponding stochastic models.
High Repetition Rate Fiber Laser Systems for High Field Physics
Authors: Hädrich S. , Krebs M. , Nolte S. , Limpert J. , Tünnermann A.
Published: April 2013

We demonstrate the generation of XUV radiation with wavelengths down to 23.9 nm (52 eV) at 50 kHz via high harmonic generation of a fiber chirped pulse amplification system. At repetition rates of 100 kHz and 200 kHz we were able to obtain 27.8 nm (45 eV) and 35.5 nm (35 eV), respectively. Furthermore, we show latest experimental results on post compression of the same fiber chirped pulse amplification system via self-phase modulation in hollow core fibers pathing the way towards more efficient high harmonic generation with even shorter wavelengths. Pulses as short as 70 fs with 200 μJ pulse energy at 50 kHz and with 77 fs have been obtained owing a peak power of 2 GW.
Recent Advances of Table-Top Soft x-ray Lasers
Authors: Rocca J. J. , Furch F. J. , Reagan B. A. , Wang Y. , Alessi D. , Martz D. , Luther B. M. , Curtis A. H. , Meehan S. P. , Domingue S. , Kemp D.
Published: April 2013

We review recent advances in the development of high repetition rate table-top soft X-ray lasers that includes their extension to wavelengths down to 10.9 nm and the first demonstration of an all-diode-pumped soft x-ray laser.
Amplification of Picosecond Pulses Generated in a Carbon Nanotube Modelocked Thulium Fiber Laser
Authors: McComb Timothy S. , Kadwani Pankaj , Sims R. Andrew , Shah Lawrence , Willis Christina C. C. , Frith Gavin , Sudesh Vikas , Samson Bryce , Richardson Martin
Published: April 2013

Generation of 5ps, 32pJ pulses from a carbon nanotube modelocked thulium fiber oscillator and their amplification to 0.6W average power, 2.6kW peak power, 13nJ pulses by an LMA thulium fiber amplifier is discussed.
Intrinsic Reduction of the Depolarization in Nd:YAG Crystals
Authors: Tünnermann Henrik , Puncken Oliver , Weßels Peter , Frede Maik , Kracht Dietmar , Neumann Jörg
Published: April 2013

Thermally induced depolarization in Nd:YAG lasers can be reduced by choice of the crystal cut. Experimental results and corresponding simulations at pump powers around 140W are presented for [111]-, [100]-and [110]-cut crystals.
Thulium Fiber Lasers Stabilized by a Volume Bragg Grating in High Power, Tunable and Q-Switched Configurations
Authors: McComb Timothy S. , Shah Lawrence , Willis Christina C. C. , Sims R. Andrew , Kadwani Pankaj , Sudesh Vikas , Richardson Martin
Published: April 2013

Thulium fiber lasers are spectrally stabilized using a volume Bragg grating. 159 W power and >100 nm tuning range are achieved in CW configurations, and pulses <115 ns with >350 μJ are generated when Q-switched.
Generation of Cylindrical Vector Beams of a Single Higher Order Transverse Mode
Authors: Ito Akihiko , Kozawa Yuichi , Sato Shunichi
Published: April 2013

Generation of cylindrical vector beams of a single higher order transverse mode is demonstrated using a rear mirror with a low reflectivity area near the beam axis. Both Laguerre-Gaussian and Bessel-Gaussian vector beams are identified.
Phase Locking Control of the multichannel holographic laser system with the help of passive Q-switch
Authors: Basiev Tasoltan T. , Fedin Alexander V. , Gavrilov Andrey V. , Smetanin Sergey N.
Published: April 2013

Method of phase-locking control of the multichannel holographic laser system by use of a passive Q-switch is proposed. For the first time a phase-locked oscillation of the multichannel Nd:YAG-laser system with synchronous giant pulse trains output is realized with an interference pattern contrast of up to 0.81.
The effect of the longitudinal electric field of a radially polarized laser beam for second harmonic generation
Authors: Kozawa Yuichi , Ohtsu Akihiko , Sato Shunichi
Published: April 2013

Second harmonic generation is demonstrated for radially and azimuthally polarized beams. The contribution of longitudinal electric field generated by a focused radially polarized beam is clearly distinguished from that by an azimuthally polarized beam.
Diode Side Pumping of a Gain Guided, Index Anti-guided Large Mode Area Neodymium Fiber Laser
Authors: Hageman W. , Chen Y. , Bass M. , Sudesh V. , McComb T. , Richardson M. , Kim G.
Published: April 2013

Diode side pumping of a gain guided, index anti-guided neodymium doped fiber laser is demonstrated. This method of pumping may lead to a scalable approach to create high power, extremely large mode area fiber lasers.
Continuous-wave Yb-doped sesquioxide thin disk lasers with up to 300 W output power and 74% efficiency
Authors: Heckl O. H. , Peters R. , Kränkel C. , Baer C. R. E. , Saraceno C. J. , Südmeyer T. , Petermann K. , Keller U. , Huber G.
Published: April 2013

We obtained 301 W of output power, 88% slope efficiency, and 74% optical-to-optical efficiency with VBG-diode-pumped Yb:Lu2O3 thin disk lasers. Yb:Sc2O3 and Yb:LuScO3 showed comparable performance, delivering 264 W and 250 W of output power, respectively.
Directly Chirped Laser Source for Chirped-Pulse Amplification
Authors: Xin R. , Zuegel J. D.
Published: April 2013

A programmable, all-fiber, chirped-pulse seed laser system based on direct phase modulation produces 2.5-ns optical pulses with 0.78-nm bandwidth centered at 1053 nm that are suitable for chirped-pulse amplification.
High average power 5 GW peak power fiber laser pumped few-cycle OPCPA system
Authors: Rothhardt J. , Hädrich S. , Seise E. , Tavella F. , Willner A. , Düsterer S. , Schlarb H. , Feldhaus J. , Limpert J. , Rossbach J. , Tünnermann A.
Published: April 2013

We report on a fiber pumped high power few cycle OPCPA system delivering 8 fs pulses at 96 kHz repetition rate. The amplified pulse energy is as high as 70 μJ which corresponds to 6.7 W average power and the pulse peak power is as high as 5 GW. Additionally, the seed oscillator is CEP stabilized and the CEP stability of the amplified pulses is measured. Furthermore, high harmonic generation up to the 35th order (20.9 nm) in demonstrated in a Krypton gas jet.
Performance Trade-Offs for High-Repetition-Rate Noncollinear Optical Parametric Amplifiers
Authors: Bromage J. , Dorrer C. , Zuegel J. D.
Published: April 2013

MHz-repetition-rate noncollinear optical parametric amplifiers are experimentally evaluated, focusing on the trade-offs that depend on pump-signal spatial walk-off in β -barium borate. Walk-off compensation improves beam uniformity, but parasitic second-harmonic generation limits the signal tuning range.
Idler Pulse Compression with an Identical Positive Dispersive Media to Signal Pulse Stretcher in Ultrafast Optical-Parametric Chirped-Pulse Amplification
Authors: Akahane Yutaka , Ogawa Kanade , Tsuji Koichi , Aoyama Makoto , Yamakawa Koichi
Published: April 2013

Optical-parametric chirped-pulse amplification with a positive dispersive media for both signal pulse stretcher and idler compressor was demonstrated. By compressing negatively-chirped idler pulses, high power sub-100 fs pulses were successfully obtained in this manner.
50W pico-second Nd:GdVO4 bounce laser with a phase-conjugate mirror
Authors: Morimoto Yasuhito , Miyamoto Katsuhiko , Maeda Yuichi , Omatsu Takashige
Published: April 2013

A 50W pico-second dual Nd:GdVO4 bounce amplifier system with a phase-conjugate mirror is demonstrated. The system has also been extended to generate pico-second mid-infrared radiation with frequency ranges of 1.55-1.57µm and 3.4-3.3 µm.
Concept for Cryogenic kJ-Class Yb:YAG Amplifier
Authors: Ertel K. , Hernandez-Gomez C. , Mason P. D. , Musgrave I. O. , Ross I. N. , Collier J. L.
Published: April 2013

More and more projects and applications require the development of ns, kJ-class DPSSL systems with multi-Hz repetition rate. We present an amplifier concept based on cryogenically cooled Yb:YAG, promising high optical-to-optical efficiency and high gain.
Semiconductor Disk Lasers Incorporating InP/GaInP Quantum Dots for 716-755 nm Emission
Authors: Schlosser Peter J. , Hastie Jennifer E. , Calvez Stephane , Krysa Andrey B. , Dawson Martin D.
Published: April 2013

We report demonstration of semiconductor disk lasers based on InP/GaInP quantum dots for TEM00 emission from 716-755nm, and up to 25nm tuning from a single source. Maximum output power of 52mW was achieved at 739nm.
0.5 MHz 50fs μJ-class Ultrafast Laser Amplifier System
Authors: Zhang Xiaoshi , Backus Sterling J , Liu Hsiao-hua , McKinnie Iain T , Kapteyn Henry C , Murnane Margaret M
Published: April 2013

We report an innovative and robust ultrafast Ti:sapphire regenerative amplifier system accessing a new operating regime tunable from 50kHz up to 500kHz-repetition-rate, up to 10μJ, 50fs pulses, enabling applications in micromachining, imaging, and spectroscopy.
First CEO frequency measurement of a SESAM-modelocked 1.5-µm solid-state laser oscillator
Authors: Pekarek S. , Stumpf M. C. , Oehler A. E. H. , Südmeyer T. , Dudley J. M. , Keller U.
Published: April 2013

We present a self-referencable frequency comb by optimized octave-spanning supercontinuum generation of a diode-pumped 170-fs Er:Yb:glass-laser with 110 mW power. The f-to-2f CEO frequency has 49-dB signal-to-noise and >10-times narrower bandwidth than free-running 1.5-µm fiber-systems.
Visible Spectrum Frequency Comb for Astronomical Spectrograph Calibration
Authors: Benedick A. J. , Chang G. , Glenday A. , Li C. H. , Phillips D. F. , Walsworth R. L. , Kärtner F. X.
Published: April 2013

We have developed a visible wavelength frequency comb at 420nm with a 21GHz mode spacing to calibrate astronomical spectrographs used in searches for planets similar to the Earth near stars similar to the Sun.
Pressure-controlled phase-matching to the third harmonic in Ar-filled hollow core PCF
Authors: Nold J. , Joly N. Y. , Hölzer P. , Podlipensky A. , Russell P. St.J.
Published: April 2013

Hollow core photonic crystal fibre filled with Ar at pressures of 5 bar offers long interaction lengths and high nonlinearity. Pressure-tuned phase-matched third harmonic and supercontinua are generated from 30 fs pulses at 800 nm.
Generation of powerful tunable mid-infrared picosecond laser radiation using frequency conversion in periodically poled Lithium niobate
Authors: Anstett Gregor , Ruebel Felix , L’huillier Johannes A.
Published: April 2013

The generation of tunable mid-infrared picosecond laser radiation in the spectral range from 3-5 µm by nonlinear frequency conversion in PPLN is reported. More than 3 W output power at 3 µm and 1 W at 4.5 µm were achieved.
Ultrafast, High Power Laser Technologies: Challenges and Perspectives
Authors: Yamakawa K.
Published: April 2013

Recent advances in ultrafast, high power lasers using chirped-pulse amplification (CPA) are reviewed. Further development of emerging diode-pumped, cryogenically-cooled Yb-doped solid-state CPA lasers is also described.
Efficient ignition of a real automobile engine by a high brightness, passively Q-switched Cr:YAG/Nd:YAG micro-laser
Authors: Tsunekane Masaki , Taira Takunori , Inohara Takayuki , Kanehara Kenji
Published: April 2013

A 0.3PW/sr-cm2, high brightness passively Q-switched Cr:YAG/Nd:YAG micro-laser was tested for ignition of a real automobile engine. Stable engine operation was demonstrated with an ignition optical energy of 2.3mJ, lowest ever reported.
Multi-disciplinary Lidar Applications
Authors: Barup Kerstin , Brydegaard Mikkel , Guan Zuguang , Hedenström Anders , Hellström Jenny , Lewander Märta , Lundin Patrik , Löfstedt Christer , Merdasa Aboma , Olsson Annika , Runemark Anna , Somesfalean Gabriel , Svensson Erik , Wellenreuther Maren , Åkesson Susanne , Svanberg Sune
Published: April 2013

Lidar is a powerful technique normally associated with atmospheric monitoring. However, lidar techniques, also of the laser-induced fluorescence and laser-induced breakdown spectroscopy varieties, provide many new possibilities in unconventional fields including cultural heritage and ecological applications.
Coherent Lensless Imaging
Authors: Fienup James R.
Published: April 2013

Coherent imaging has numerous advantages over incoherent imaging, but at a cost of requiring coherent laser illumination.
Creating Aperture Masks in Phase Space
Authors: Horstmeyer R. , Oh S.B.
Published: April 2013

The Wigner distribution is used to model the PSF of an aperture mask at different defocus planes. Algorithmic methods of determining an optimal mask pattern for a desired set of impulse responses are investigated.
Near-Field Imaging of Infrared Antennas
Authors: Krenz Peter , Boreman Glenn , Lail Brian , Olmon Robert , Raschke Markus
Published: April 2013

Far field radiation at 28.3 THz is coupled into a coplanar strip line using a dipole antenna. A scattering type scanning near field optical microscope is used to measure the electric field distribution on the transmission line. The standing wave equation is fitted to the measured data and the attenuation and propagation constants are determined.
Nanophotonics for Solid-State Imaging
Authors: Catrysse Peter B. , Verslegers Lieven , Fesenmaier Christian C. , Huo Yijie
Published: April 2013

I explore the challenges and opportunities for nanophotonics that have emerged in solid-state image sensors as pixel size is scaling down to the single wavelength range, following scaling of feature sizes in advanced semiconductor processes.
MODELING THE PERFORMANCE OF TURBULENCE MITIGATION ALGORITHMS IN TARGETING IMAGERS
Authors: Espinola Richard L. , Cha Jae
Published: April 2013

Mitigation algorithms can improve the target acquisition performance of imaging systems in atmospheric turbulence. We quantify this improvement using perception tests and develop a model that predicts sensor/observer ID performance with software-based turbulence mitigation algorithms.
Computational 3D Fluorescence Microscopy Imaging
Authors: Mukherjee Amaradri , Preza Chrysanthe
Published: April 2013

We show cell images from two different approaches of computational 3D fluorescence imaging integrated on a single wide-field fluorescence microscope system and discuss advantages and disadvantages of the two techniques under investigation.
High-resolution, superfast 3-D imaging using a phase-shifting method
Authors: Zhang Song , Gong Yuanzheng , Laughner Jacob , Lou Qing , Efimov Igor R. , van der Weide Daniel
Published: April 2013

We presents a system to realize 333 fps 3-D shape measurement speed at 768 × 768 resolution. It utilizes the DLP Discovery platform to realize 3-D shape measurement by using a defocusing method.
Novel MEMS Deformable Mirror for Focus Control and Aberration Correction
Authors: Kaylor Brant M. , Roos Peter A. , Jeffrey Lutzenberger B. , Dahl Jason R. , Dickensheets David L.
Published: April 2013

Electrostatically actuated MEMS mirrors for focus control have been fabricated. Deflection over 7.3 µm, which corresponds to 67% of the air gap and a focal length of 154 mm, has been achieved using closed-loop control. Low-order aberrations have been corrected and the devices have been utilized in a simple imaging system.
Modeling of 2D/3D Ladar systems: experimental assessment
Authors: Hespel Laurent , Anna Guillaume , Rivière Nicolas , Bonnefois Aurélie , Velluet Marie-Thérèse , Hamoir Dominique
Published: April 2013

We developed two numerical models to address respectively, 2D Flash and 3D Ladar imaging. After a short description of the models used, a comparison of numerical and experimental results is conducted.
Focal Length Invariance of Perceptual Image Quality for Long Range Imaging Applications
Authors: Lentz Joshua K. , Harvey James E.
Published: April 2013

For long range imaging applications, perceptual image quality will not vary with focal length. Theoretical justification and Modulation Transfer Function (MTF) evidence are presented.
OF-CEAS detects leak rates down to 5⋅10−9 mbar.L/s
Authors: Pailloux A. , Cousin J. , Romanini D. , Chenevier M. , Gherman T. , Gallou C. , Weulersse J-M
Published: April 2013

Leak detection and localization is an issue for facility and population safety and security. The paper shows that low leak rates of methane, down to 5 10−9mbar.L/s, are detected by OF-CEAS technique under atmospheric pressure.
Comparison of Quartz-enhanced Photoacoustic Spectroscopy and Conventional Photoacoustic Spectroscopy based Detectors
Authors: Dong Lei , Lewicki Rafal , Tittel Frank K. , Kosterev Anatoliy A.
Published: April 2013

Performance of quartz-enhanced photoacoustic spectroscopy and conventional photoacoustic spectroscopy based detectors applied to trace gas sensing was compared. Nitrogen with 10 ppmv of acetylene and a diode laser accessing 6529.17 cm−1 absorption line were used.
Atmospheric Pressure Femtosecond Laser Imaging Mass Spectrometry
Authors: Coello Yves , Jones A. Daniel , Gunaratne Tissa C. , Dantus Marcos
Published: April 2013

We demonstrate a novel imaging mass spectrometry technique that uses femtosecond laser pulses to ionize the sample at ambient conditions. The technique provides 10µm lateral resolution, as demonstrated here with a chemical image of vegetable cells.
High-resolution Imaging of Turbulence Structures in Jet Flames and Non-reacting Jets with Laser Rayleigh Scattering
Authors: Frank Jonathan H. , Kaiser Sebastian A.
Published: April 2013

Turbulence structures in jet flames and non-reacting jets are studied with laser Rayleigh imaging. Comparisons of length scales and morphology of dissipation structures in reacting and non-reacting flows reveal effects of heat release on turbulence.
Measurements of Liquid Film Thickness by Tracer LIF, Raman Scattering and Diode Laser Absorption Spectroscopy
Authors: Greszik D. , Yang H. , Dreier T. , Schulz C.
Published: April 2013

Three different diagnostics techniques are compared to measure the liquid film thickness on a transparent quartz glass plate. The comparison shows a consistent trend and reveals application potentials.
Laser Diagnostic Techniques for Shock Tube Studies of Combustion Chemistry
Authors: Hanson R. K.
Published: April 2013

Laser-based absorption techniques, used to probe species time-histories in shock tube experiments of combustion chemistry, are described. A variety of laser sources are used, providing wavelengths from the deep UV to the mid-IR.
Towards Quantitative Measurements of Soot Concentrations in Strongly Sooting Turbulent Jet Diffusion Flames
Authors: Shaddix Christopher R. , Zhang Jiayao , Schefer Robert W.
Published: April 2013

Two-dimensional laser-induced incandescence has been used to quantify soot properties in strongly sooting turbulent nonpremixed flames fueled by ethylene and JP-8 surrogate, despite strong laser attenuation and signal trapping.
Microwave-assisted LIBS: Towards a new tool for trace element detection and molecular plasma spectrochemistry
Authors: Liu Yuan , Baudelet Matthieu , Richardson Martin
Published: April 2013

This study shows the modification of molecular and atomic signals in microwave-assisted laser- induced plasma spectroscopy and the potential for trace element detection and molecular plasma spectroscopy.
Spatial Confinement Effects in Laser-Induced Breakdown Spectroscopy
Authors: Shen X. K. , He X. N. , Huang H. , Lu Y. F.
Published: April 2013

It is very important to improve the detection sensitivity of laser-induced breakdown spectroscopy. In this work, spatial confinement effects of laser-induced Al plasmas using cylindrical walls have been investigated by emission spectra and fast imaging.
Tropical Woodland Biomass Burning and Carbon Emission: a case study in Sudan
Authors: Wu Weicheng , De Pauw Eddy
Published: April 2013

This paper reports on an integrated assessment in Sudan of woodland biomass loss in a tropical African savannah based on remote sensing. We used 272 winter MODIS reflectance images (500m resolution, 16-day interval) between Oct 15 and Mar 07 from 2000 to 2009 to produce a series of Normalized Burn Ratio (NBR) and Normalized Difference Vegetation Index (NDVI). The technique of differencing and thresholding on NBR combined with supervised classification on MODIS images was applied to identify the burned areas and assess the severity of burning. To verify the processing results from MODIS data, we used 35 Landsat ETM+ images taken during the winter periods between 2000 and 2003 as well as a number of QuickBird images between 2004 and 2009 available in Google Earth. Regression models of woody biomass developed earlier by the authors were applied to estimate the burnt woody biomass and carbon emission into atmosphere.
Using Lidar Surface Returns to Reduce Uncertainty in Aerosol Retrievals from Elastic Scatter Lidar
Authors: Reagan John , McPherson Christopher
Published: April 2013

Lidar observations obtained from the LITE Mission, GLAS on board ICESat and CALIOP on board CALIPSO have clearly demonstrated the wealth of quantitative information about clouds and aerosols that may be retrieved from spaceborne lidar measurements. All three of these lidars are elastic scatter type lidars. As is well known, backscatter and extinction profiles cannot be unambiguously retrieved from simple elastic scatter lidar returns without an assumption linking extinction and backscatter (e.g., that the extinction-to-backscatter ratio, or lidar ratio is spatially constant through a solution layer) as well as requiring additional boundary value or parameter specification information (e.g., layer optical depth or specification of the lidar ratio). The initial retrieval approach that has been employed for the GLAS and CALIOP observations is to use climatological/geographical based look-up tables for assigning scatterer type and the associated lidar ratio value for 532 nm profile retrievals when alternate, less uncertain methods for either estimating the lidar ratio or providing the needed auxiliary optical depth information are unavailable. Use of depolarization measurement information, as available with the CALIOP lidar, plus assessing the 532 nm to 1064 nm attenuated backscatter signal ratio (color ratio) provides additional information for inferring the scatterer type and associated 532 nm lidar ratio, but this still does not take full advantage of the available dual-wavelength information, or provide a clear consistency check of the lidar ratio assumed in the retrieval. Spectral ratio constraints in the form of the Constrained Ratio Aerosol Model-fit (CRAM) retrieval approach [1,2], which applies aerosol modeling in order to limit the ambiguity inherent in aerosol retrievals from elastic scatter lidar measurements, may be used to further bound/reduce uncertainty in the retrievals and confirm self-consistency in the assumed lidar ratio selection. The CRAM approach has been successfully applied to both GLAS and CALIOP observations [3,4].
Evolution of Vegetation First Derivative Spectra over the Summer-to-Autumn Transition
Authors: Cipar John , Cooley Thomas
Published: April 2013

We use derivative analysis to study changes in reflectance during the period of deciduous leaf senescence between summer and autumn. Temporal changes are caused by loss of light-absorbing chlorophyll, allowing light scattering to dominate reflectance characteristics.
Fundamental Limit of Nanophotonic Light-trapping in Solar Cells
Authors: Yu Zongfu , Raman Aaswath , Fan Shanhui
Published: April 2013

We use a rigorous electromagnetic approach to develop a light-trapping theory, which reveals that the conventional limit can be substantially surpassed in nanophotonic regimes, opening new avenues for highly efficient solar cells.
Tools Development for CPV Characterization Based On CCD Camera Measurements
Authors: Herrero R. , Domínguez C. , Antón I. , Askins S. , Sala G.
Published: April 2013

Two characterization techniques based on a CCD camera have been developed: an inverse illumination method based on cell light emission and a lens deformation analysis method. Its application to a specific CPV technology is presented.
Seasonal and Low Light Performance of a Dual Aperture Holographic Planar Concentrator Photovoltaic Module
Authors: Russo Juan Manuel , Castillo Jose , Aspnes Eric , Rosenberg Glenn
Published: April 2013

Dual aperture holographic planar concentrator modules are compared to single aperture modules for a seasonal period of nine months. Seasonal, clear and cloudy day power and energy curves are presented to compare the modules.
Antireflection Coating Optimization for Concentrator Solar Cells
Authors: Victoria M. , Domínguez C. , Antón I. , Sala G.
Published: April 2013

When optimizing antireflection coating for concentrator solar cells, the incidence angles distribution and the broad spectral bandwidth, must be considered. Here, numerical optimization of ARC layer thicknesses and spectral transmission characterization are presented.
Radial Coupling Method for Orthogonal Concentration within Planar Micro-Optic Solar Collectors
Authors: Karp Jason H. , Tremblay Eric J. , Ford Joseph E.
Published: April 2013

We present an orthogonal concentration method to further confine sunlight within planar solar collectors. Radial-oriented couplers create micro-optic solar concentrators with >375× geometric concentration and a 20% reduction in guiding loss.
Low Concentration Planar Holographic CIGS
Authors: Castillo Jose E. , Russo Juan M. , Aspnes Eric D. , Rosenberg Glenn A.
Published: April 2013

We present the results of combining CIGS cells with diffractive film. The film, originally designed for silicon solar applications worked well with the CIGS, yielding a significant boost in performance, especially at low light levels.
Theoretical Aspects of Light Collection in Solar Concentrators
Authors: Parretta A. , Zampierolo L. , Roncati D.
Published: April 2013

The theory of light collection in solar concentrators irradiated in the “direct” mode (from input aperture) is revisited and new concepts are introduced. Application of the theory is made mainly to nonimaging (CPC) concentrators.
Real time optical monitoring of properties of silicon thin film solar panels
Authors: Atanasoff George
Published: April 2013

Optical monitoring was performed during deposition of a variety of amorphous and polycrystalline silicon absorbers inside the chamber during solar panel manufacturing with the purpose of providing adaptive control of the film quality in real time. We monitored the specular and diffuse reflectance in a broad spectral region and at one fixed wavelength simultaneously. The results show optical constant and material bandgap inhomogeneity of the growing films as well as film thickness non-uniformity over the area of the panel. This information gives the manufacturer the ability to improve the film quality as it is being deposited, increase the panel conversion efficiency, improve manufacturing yield and reduce cost.
A Semi-analytical Model and Characterization Techniques for Concentrated Photovoltaic Multijunction Solar Cells
Authors: Zhang Y.-H. , Ding D. , Johnson S. R. , Lim S. H.
Published: April 2013

A semi-analytical model is established by extending the detailed balance models to explicitly elucidate the impact of nonradiative recombination and other aspects of actual devices, including photon recycling, spontaneous emission coupling, and non-ideal absorptance and emittance. Through which many important practical design parameters for concentrated photovoltaic multijunction solar cells are taken into account, such as bandgap energy, junction number, solar concentration, and material quality expressed as Shockley-Read-Hall recombination saturation current density. The model can accurately predict subcell layer thicknesses and bandgaps as function of material quality. Novel characterization techniques for multijunction solar cells are also established to measure the external quantum efficiency and to explain the commonly encountered artifacts under practical test conditions.
Pancreatic β-Cell Response to Increased Metabolic Demand and to Pharmacologic Secretagogues Requires EPAC2A
Authors: Song Woo-Jin , Mondal Prosenjit , Li Yuanyuan , Lee Suh Eun , Hussain Mehboob A.
Published: April 2013

Incretin hormone action on β-cells stimulates in parallel two different intracellular cyclic AMP-dependent signaling branches mediated by protein kinase A and exchange protein activated by cAMP islet/brain isoform 2A (EPAC2A). Both pathways contribute toward potentiation of glucose-stimulated insulin secretion (GSIS). However, the overall functional role of EPAC2A in β-cells as it relates to in vivo glucose homeostasis remains incompletely understood. Therefore, we have examined in vivo GSIS in global EPAC2A knockout mice. Additionally, we have conducted in vitro studies of GSIS and calcium dynamics in isolated EPAC2A-deficient islets. EPAC2A deficiency does not impact GSIS in mice under basal conditions. However, when mice are exposed to diet-induced insulin resistance, pharmacologic secretagogue stimulation of β-cells with an incretin hormone glucagon-like peptide-1 analog or with a fatty acid receptor 1/G protein–coupled receptor 40 selective activator, EPAC2A is required for the increased β-cell response to secretory demand. Under these circumstances, EPAC2A is required for potentiating the early dynamic increase in islet calcium levels after glucose stimulation, which is reflected in potentiated first-phase insulin secretion. These studies broaden our understanding of EPAC2A function and highlight its significance during increased secretory demand or drive on β-cells. Our findings advance the rationale for developing EPAC2A-selective pharmacologic activators for β-cell–targeted pharmacotherapy in type 2 diabetes.
Structure-Function Relationship Between Corneal Nerves and Conventional Small-Fiber Tests in Type 1 Diabetes
Authors: Sivaskandarajah Gavasker A. , Halpern Elise M. , Lovblom Leif E. , Weisman Alanna , Orlov Steven , Bril Vera , Perkins Bruce A.
Published: April 2013

OBJECTIVE

In vivo corneal confocal microscopy (IVCCM) has been proposed as a noninvasive technique to assess small nerve fiber structural morphology. We investigated the structure-function relationship of small fibers in diabetic sensorimotor polyneuropathy (DSP).

RESEARCH DESIGN AND METHODS

Ninety-six type 1 diabetic subjects with a spectrum of clinical DSP and 64 healthy volunteers underwent IVCCM examinations to determine corneal nerve structure, including corneal nerve fiber length (CNFL), fiber density (CNFD), branch density (CNBD), and fiber tortuosity (CNFT). Small nerve fiber function was assessed by cooling detection thresholds (CDTs), axon reflex–mediated neurogenic vasodilatation in response to cutaneous heating by laser Doppler imaging flare technique (LDIFLARE), and heart rate variability (HRV). Linear associations between structural and functional measures in type 1 diabetic subjects were determined using Spearman correlation coefficients and linear regression analysis.

RESULTS

Of the type 1 diabetic subjects, with a mean age of 38.2 ± 15.5 years and a mean HbA1c of 7.9 ± 1.4%, 33 (34%) had DSP according to the consensus definition. Modest correlations were observed between CNFL, CNFD, and CNBD and all functional small-fiber tests (rs = 0.25 to 0.41; P ≤ 0.01 for all comparisons). For example, quantitatively every 1 mm/mm2 lower CNFL was associated with a 0.61°C lower CDT, a 0.07 cm2 lower LDIFLARE area, and a 1.78% lower HRV. No significant associations were observed for CNFT and the functional small-fiber measures.

CONCLUSIONS

Small nerve fiber structural morphology assessed by IVCCM correlated well with functional measures of small nerve fiber injury. In particular, CNFL, CNFD, and CNBD demonstrated clear structure-function relationships.
Intrapelvic sciatic notch schwannoma: microsurgical excision using the infragluteal approach
Authors: Montano Nicola , Novello Mariangela , D'Alessandris Quintino Giorgio , Magarelli Nicola , Pallini Roberto , Lauriola Libero , Fernandez Eduardo
Published: April 2013

Benign neurogenic tumors at the sciatic notch that are purely intrapelvic have rarely been reported. Because of this tumor's particular position, a transabdominal or combined transabdominal-gluteal approach is usually used to achieve total resection. However, the transabdominal approach carries a remarkable surgical risk because of the manipulation of intraperitoneal organs. Here, the authors describe a 59-year-old woman harboring a purely intrapelvic sciatic notch schwannoma extrinsic to the sciatic nerve, which was totally removed via the infragluteal approach preserving sciatic function. The postoperative course was uneventful. The infragluteal approach can be safely used for the effective resection of intrapelvic benign neurogenic tumors at the sciatic notch that are extrinsic to the sciatic nerve, avoiding the more invasive and risky transabdominal approach.