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Mid-latitude maritime glaciers are responding quickly and directly to climate change. This response is expected to continue, and will result in maritime glaciers making a large contribution to sea level rise over the coming decades. Maritime glaciers in the New Zealand Southern Alps provide an opportunity to learn more about climate–glacier mass balance relationships in a high precipitation setting, and how these relationships might change in the future. Ice core and direct glaciological measurements are used to construct a 24-year record of net accumulation, the longest of its type in New Zealand. We demonstrate that variations in net accumulation on Tasman Glacier are more strongly influenced by temperature than by precipitation. Further, it is temperature during the ablation season that exerts most control. Atmospheric circulation patterns, in particular the state of the El Nino Southern Oscillation (ENSO) and Southern Annular Mode (SAM), were found to influence net accumulation. When the SAM is positive and the ENSO in a La Nina phase, easterly and northerly wind anomalies are enhanced, temperatures increase in the Southern Alps region and more negative glacier mass balances result. Conversely when SAM is negative and ENSO in an El Nino phase, westerly and southerly wind anomalies occur, and temperatures decrease in the Southern Alps region. In this case, glacier mass balance is more likely to be positive. However, relationships between glacier mass balance and these atmospheric circulation modes are not simply linear, with some of the lowest net accumulation years associated with inverse polarity between the SAM and the ENSO.

Understanding relationships between snow accumulation and synoptic climatology is important for assessing the way in which future climate variability will impact on glacier mass balance. However, few studies have as yet examined these relationships. Variability in snow accumulation on mid-latitude glaciers is strongly influenced by atmospheric circulation, orography, and redistribution of snow by wind. Very little is known about these processes in the New Zealand Southern Alps, where it is assumed that west-facing glaciers receive higher snow totals. However, few measurements are available to test this hypothesis. These processes were investigated over a 21-day period in winter 2008 on glaciers located west (Franz Josef Glacier) and east (Tasman Glacier) of the Main Divide of the Southern Alps. We directly measured snow accumulation and considered how it was affected by synoptic weather regime and location with respect to the Main Divide. Both glaciers received ∼75% of their snowfall during troug...

Coverage of ice velocities in the central part of the Southern Alps, New Zealand, is obtained from feature tracking using repeat optical imagery in 2002 and 2006. Precise orthorectification, co-registration and correlation is carried out using the freely available software COSI-Corr. This analysis, combined with short times between image acquisitions, has enabled velocities to be captured even in the accumulation areas, where velocities are lowest and surface features ephemeral. The results indicate large velocities for mountain glaciers (i.e. up to ∼5 m d−1) as well as dynamic changes in some glaciers that have occurred between 2002 and 2006. For the steep and more responsive Fox and Franz Josef Glaciers the speed increased at the glacier snout during the advance period, while the low-angled and debris-covered Tasman Glacier showed no measurable velocity change. Velocity increases on the steeper glaciers are the result of an observed thickening and steepening of the glacier tongues as they moved from a retreat phase in 2002 to an advance phase in 2006. This contrasting behaviour is consistent with historic terminus position changes. The steeper glaciers have undergone several advance/retreat cycles during the observation period (1894 to present), while the low-angled glacier showed little terminus response until retreat resulting from the accelerating growth of a proglacial lake commenced in 1983.

Net accumulation measurements from two glaciers located on opposite sides of the New Zealand Southern Alps were used to explore processes controlling spatial variability. The degree of variability, as measured by the spatial variogram, differed in each of the three successive years, but the lowest variance occurred on both glaciers in March 2008, after a hot and dry summer. Strong relationships between net accumulation and elevation within the accumulation area were only found on Franz Josef Glacier (FJG), despite this being the primary control used in glacier mass balance modelling. Interaction between wind and topography was found to be important to the distribution of net accumulation on both glaciers. The crevasse stratigraphy method is an ideal way to gain good spatial coverage of net accumulation, and particularly suited to glaciers with high annual precipitation. Copyright © 2010 John Wiley & Sons, Ltd.

Background Chronic pain is common and challenging to treat. Although cognitive behavioral therapy (CBT) is efficacious, its benefit in disadvantaged populations is largely unknown. Objective To evaluate the efficacy of literacy-adapted and simplified group CBT versus group pain education (EDU) versus usual care. Design Randomized controlled trial. (ClinicalTrials.gov: NCT01967342). Setting Community health centers serving low-income patients in Alabama. Patients Adults (aged 19 to 71 years) with mixed chronic pain. Interventions CBT and EDU delivered in 10 weekly 90-minute group sessions. Measurements Self-reported, postintervention pain intensity (primary outcome) and physical function and depression (secondary outcomes). Results 290 participants were enrolled (70.7% of whom were women, 66.9% minority group members, 72.4% at or below the poverty level, and 35.8% reading below the fifth grade level); 241 (83.1%) participated in posttreatment assessments. Linear mixed models included all randomly assigned participants. Members of the CBT and EDU groups had larger decreases in pain intensity scores between baseline and posttreatment than participants receiving usual care (estimated differences in change scores-CBT: -0.80 [95% CI -1.48 to -0.11]; P = 0.022; EDU: -0.57 [CI, -1.04 to -0.10]; P = 0.018). At 6-month follow-up, treatment gains were not maintained in the CBT group but were still present in the EDU group. With regard to physical function, participants in the CBT and EDU interventions had greater posttreatment improvement than those receiving usual care, and this progress was maintained at 6-month follow-up. Changes in depression (secondary outcome) did not differ between either the CBT or EDU group and the usual care group. Limitations Participants represented a single health care system. Self-selection bias may have been present. Conclusion Simplified group CBT and EDU interventions delivered at low-income clinics significantly improved pain and physical function compared with usual care. Primary funding source Patient-Centered Outcomes Research Institute.

The sensitivity of glaciers to climatic change is key information in assessing the response and sea-level implications of projected future warming. New Zealand glaciers are important globally as an example of how maritime glaciers will contribute to sea-level rise. A spatially distributed energy-balance model is applied to Brewster Glacier, New Zealand, in order to calculate glacier mass balance, run-off and sensitivity to climate change. The model successfully simulates four annual mass-balance cycles. Close to half (52%) of the energy available for melt on the glacier is supplied by turbulent heat fluxes, with radiation less important, except during the winter. Model sensitivity to temperature change is one of the largest reported on Earth, at −2.0 m w.e. a−1 °C−1. In contrast, a 50% change in precipitation is required to offset the mass-balance change resulting from a 1 °C temperature change. Meltwater runoff sensitivity is also very high, increasing 60% with a 1°C warming. The extreme sensitivity of mass balance to temperature change suggests that significant ice loss will occur with even moderate climate warming.

Ten years ago, the argument for permanent ocean-bottom cables (OBC) seemed compelling. Permanent OBC deployment would provide the best possible receiver repeatability, while wide-azimuth geometry would provide improved illumination as well as fracture characterization. Hydrophone-geophone (PZ) combinations would improve demultiple. Finally, multicomponent receivers would also record shear waves that would unravel the combined effects of lithology, porosity, and fractures for reservoir characterization, as well as the combined effects of fluid replacement and pressure changes for monitoring.

Understanding the response of relatively small ice masses to climate change on a century-to-century timescale is important because of their significant contribution to sea level change in the recent past, and their likely contribution in the next century. Franz Josef Glacier, with its excellent terminus position record, location in the Southern Hemisphere, and its extreme sensitivity to climatic changes, is a key data point for understanding the magnitude and mechanisms of past and future climate changes. Here, we use a reconstructed mass balance record to drive an ice flow model which simulates the general retreat of the glacier during the 20th century. The model is then used to project future glacier variations, based on regionally downscaled climate change scenarios. The results indicate that, under a mean climate change scenario, the glacier will retreat 5 km and lose 38% of its mass by 2100. Different scenarios give a range of recession from 3.9 to 6.4 km, and a range of volume loss from 26% to 58%. On a global scale, the magnitude of the retreat is at the upper end of the range calculated for other, similar sized, glaciers.

The purpose of this study was to critically examine insitu test methods as a means for predicting settlement of shallow foundations. Accordingly, a 1.8 m (6 ft) diameter concrete footing was statically load tested. Prior to construction, insitu [standard penetration test (SPT), cone penetration test (CPT), dilatometer (DMT), and pressuremeter (PMT)] and laboratory tests were performed to determine engineering properties of the soil. Predictions of the footing settlement were made by traditional as well as finite element methods. The results of the static load test showed settlements were over predicted by all methods. However, the traditional methods provided reasonable settlement estimates using either SPT- N or back computed CPT(N) as input. Finite element analyses using either DMT or CPT derived input parameters provided reasonable settlement estimates. Finite element analyses using SPT or PMT derived input parameters provided poor settlement estimates. The Mohr–Coulomb (elastoplastic) model, accountin...

Preventing tuberculosis among the homeless has emerged as an especially difficult challenge.We assessed a 2008-2009 tuberculosis (TB) outbreak ad subsequent prevention strategies among homeless persons in metropolitan Jackson, Hinds County, Mississippi.We compared data about cases and subclinical TB infections (LTBI) among homeless persons during the outbreak and post-outbreak years, interviewed involved homeless persons, compiled observations from visits to Jackson homeless shelters and conducted literature reviews on homelessness and infectious diseases. We reviewed homeless shelter TB prevention methods adopted by other municipalities, guidelines developed by the Centers for Disease Control and Prevention (CDC), and recommendations from other official and ad hoc groups and considered their applicability to metropolitan Jackson.The Mississippi State Department of Health TB Program assisted by the CDC and other agencies, contained the Jackson-area outbreak by the end of 2009 as reflected by progressively lower TB rates among homeless persons thereafter. However, some follow-up activities and enforcement of shelter preventive measures have not been consistently maintained. Resources to prevent further outbreaks continue to be inadequate, and over-reliance on private organizations has continued. In the process, appreciation of the dynamic interaction enhancing TB risk among the homeless and incarcerated persons has emerged.Major outbreak contributors were lack of periodic TB screening among homeless shelter clients, preventive treatment compliance and follow-up difficulties among those with subclinical tuberculosis infections, interrupted preventive measures among infected persons incarcerated in local correctional facilities who disproportionately re-join Jackson's homeless community when released, inadequate attention to shelter environmental preventive strategies such as ultraviolet light germicidal irradiators and proper air-exchange/ventilation, costs of isolation housing for homeless people with full-blown tuberculosis (especially those co-infected with HIV and other infections and those with alcohol and/or other chemical dependencies), lack of adequate transportation which impacts access to evaluation and care, lack of mandated ongoing training among shelter and correctional facility staff, and inadequate attention to the societal problem of homelessness itself.Sustained adherence to local shelter and correctional facility TB prevention measures based on standards and policies proved effective in other settings is most crucial. These include requirements for periodic tuberculosis prevention and awareness training for shelter and correctional facility staff, ongoing tuberculosis screening and follow-up among homeless shelter clients and inmates of local correctional facilities, and attention to shelter and correctional facility environmental sanitation, proper ventilation, ultraviolet light fixtures and capacity/bed alignment standards.

Optical linewidth broadening through both white noise (WNS) and pseudo-random binary sequence (PBRS) phase modulation are effective techniques for suppressing stimulated Brillouin scattering (SBS) in high- power fiber amplifiers. However, detailed studies comparing both coherent beam combining and SBS suppression of these phase modulation schemes have not been reported. In this study, a passive fiber cutback experiment is performed comparing the SBS threshold enhancement factor of a PRBS and WNS broadened seed as a function of linewidth and fiber length. Particularly, assuming an optimal PRBS pattern is chosen, pseudo-random modulation provides superior SBS suppression than WNS for a given fiber length and signal linewidth. Furthermore, two WNS and PRBS modulated 150 W fiber lasers are coherently combined to measure and compare the combining efficiency, beam quality, and coherence as a function of optical path length difference. Notably, the discrete spectral density of PRBS modulation provides a re-coherence effect where the lasers periodically come back into phase. Overall, this may reduce path length matching complexity in coherently combined fiber laser systems.

The paper compares two finite element time domain solvers for transient electromagnetic simulation of multiscale structures. The first solver is based on a dual-field implicit-explicit formulation. By limiting the number of implicit elements, the solver closely resembles nodal discontinuous Galerkin and has better scalability in memory requirement and multithreading for solving large-scale problems. However, when the structures and features to be solved are electrically small, the explicit part of the hybrid solver is limited by the stability condition and becomes inefficient in passing low-frequency signals through the structures. We will demonstrate that the second solver based on a single-variable fully implicit formulation can better handle low-frequency applications such as electrostatic discharge and lightning strikes. It is also immune to bad meshes with extremely small or ill-shaped elements.

The Peanuts Movie presented a fantastic challenge for Blue Sky Studios: bring Charles Schulz's beloved and iconic characters into a 3D world while remaining faithful to the original comic's style and design. The characters' heads and faces posed unique problems that were difficult to solve with our existing technology. From tiny pinched mouths, to ear to ear smiles, their expressions stretched to great extremes without disturbing the clean profiles and smooth shading of their round heads. A new approach was developed to preserve and control the head shapes while allowing facial features to slide freely around those curved volumes. Additionally, Schulz removed 3 dimensional form where it diluted clarity and drew aspects of the character differently when it detracted from simple graphic appeal. Thus, their proportions and facial features change position and shape depending on their viewing angle. Due to the degree of change, a single standard three dimensional model would not suffice. To solve this issue we decided to make rig states which we called character views.

Power scaling using a higher order mode in a ribbon fiber has previously been proposed. However, methods of selecting the higher order mode and converting to a single lobe high brightness beam are needed. We propose using a multiplexed transmitting Bragg grating (MTBG) to convert a higher order mode into a single lobe beam. Using a ribbon fiber with core dimensions of 107.8 μm by 8.3 μm, we use the MTBG to select a higher order mode oscillating within the resonator with 51.4% efficiency, while simultaneously converting the higher order mode to a beam with diffraction limited divergence of 10.2 mrad containing 60% of the total power.

White noise phase modulation (WNS) and pseudo-random binary sequence phase modulation (PRBS) are effective techniques for mitigation of nonlinear effects such as stimulated Brillouin scattering (SBS); thereby paving the way for higher power narrow linewidth fiber amplifiers. However, detailed studies comparing both coherent beam combination and the SBS suppression of these phase modulation schemes have not been reported. In this study an active fiber cutback experiment is performed comparing the enhancement factor of a PRBS and WNS broadened seed as a function of linewidth and fiber length. Furthermore, two WNS and PRBS modulated fiber lasers are coherently combined to measure and compare the fringe visibility and coherence length as a function of optical path length difference. Notably, the discrete frequency comb of PRBS modulation provides a beam combining re-coherence effect where the lasers periodically come back into phase. Significantly, this may reduce path length matching complexity in coherently combined fiber laser systems.

Increasing the dimensions of a waveguide provides the simplest means of reducing detrimental nonlinear effects, but such systems are inherently multi-mode, reducing the brightness of the system. Furthermore, using rectangular dimensions allows for improved heat extraction, as well as uniform temperature profile within the core. We propose a method of using the angular acceptance of a transmitting Bragg grating (TBG) to filter the fundamental mode of a fiber laser resonator, and as a means to increase the brightness of multi-mode fiber laser. Numerical modeling is used to calculate the diffraction losses needed to suppress the higher order modes in a laser system with saturable gain. The model is tested by constructing an external cavity resonator using an ytterbium doped ribbon fiber with core dimensions of 107.8μm by 8.3μm as the active medium. We show that the TBG increases the beam quality of the system from M 2 = 11.3 to M 2 = 1.45, while reducing the slope efficiency from 76% to 53%, overall increasing the brightness by 5.1 times.

Observations show that glaciers around the world are in retreat and losing mass. Internationally coordinated for over a century, glacier monitoring activities provide an unprecedented dataset of glacier observations from ground, air and space. Glacier studies generally select specific parts of these datasets to obtain optimal assessments of the mass-balance data relating to the impact that glaciers exercise on global sea-level fluctuations or on regional runoff. In this study we provide an overview and analysis of the main observational datasets compiled by the World Glacier Monitoring Service (WGMS). The dataset on glacier front variations (∼42 000 since 1600) delivers clear evidence that centennial glacier retreat is a global phenomenon. Intermittent readvance periods at regional and decadal scale are normally restricted to a subsample of glaciers and have not come close to achieving the maximum positions of the Little Ice Age (or Holocene). Glaciological and geodetic observations (∼5200 since 1850) show that the rates of early 21st-century mass loss are without precedent on a global scale, at least for the time period observed and probably also for recorded history, as indicated also in reconstructions from written and illustrated documents. This strong imbalance implies that glaciers in many regions will very likely suffer further ice loss, even if climate remains stable.

Despite their relatively small total ice volume, mid-latitude valley glaciers are expected to make a significant contribution to global sea-level rise over the next century due to the sensitivity of their mass-balance systems to small changes in climate. Here we use a degree-day model to reconstruct the past century of mass-balance variation at ‘Ka Roimata o Hine Hukatere’ Franz Josef Glacier, New Zealand, and to predict how mass balance may change over the next century. Analysis of the relationship between temperature, precipitation and mass balance indicates that temperature is a stronger control than precipitation on the mass balance of Franz Josef Glacier. The glacier’s mass balance, relative to its 1986 geometry, has decreased at a mean annual rate of 0.02m a–1w.e. between 1894 and 2005. We compare this reduction to observations of terminus advance and retreat, of which Franz Josef Glacier has the best record in the Southern Hemisphere. For the years 2000–05 the relative mass balance ranged from –0.75 to +1.50m a–1w.e., with 2000/01 the only year showing a negative mass balance. In a regionally downscaled Intergovernmental Panel on Climate Change mean warming scenario, the annual relative mass balance will continue to decrease at 0.02m a–1w.e. through the next century.

We attempted to determine how accurately members of the public can identify venomous snakes. Six different snakes indigenous to southern California were displayed in cages for 265 people to view at a street fair. These included 4 nonvenomous snakes and 2 venomous snakes. People were asked whether the snake was venomous and the name of the snake, if they knew it. Overall, people recognized whether a snake was venomous or nonvenomous 81% of the time. They were most accurate at identifying rattlesnakes as being venomous (95%) but incorrectly identified nonvenomous snakes as being venomous 25% of the time. Men were more accurate than women, and adults were more accurate than children. Subjects were less well able to identify the exact species of snakes. The results suggest that there may be no need to capture, kill, or bring a snake to the hospital for identification, at least in this geographic area.

During February and March 2003, a series of unusual events involving supraglacial flooding and ice collapse affected an area of Franz Josef Glacier, South Westland, New Zealand. This paper describes these events and examines rainfall and river stage data in order to explain their occurrence. Relationships between rainfall events, supraglacial flooding, and stage of the Waiho River suggest that subglacial water was rerouted to a supraglacial position, most likely resulting from blockage of the subglacial route by ice collapse near the base of the main icefall on the lower part of the glacier. Review of previous literature reveals that a variety of flood and ice collapse events are frequent at Franz Josef Glacier. While this is only one of several natural hazards in the Franz Josef area, it is of considerable importance because of the large number and significant duration of tourist visits to the terminus and onto the lower part of the glacier.

The late Holocene retreat of the West Antarctic ice sheet is crucial information for assessing its current dynamics. However, data from this period for parts of the ice sheet where significant change has taken place, mainly the Ross Sea, are very sparse. Some significant dated deposits are from lakes dammed by valley glaciers, themselves dammed by the Ross Ice Sheet. The least age of these deposits is somewhat later than the retreat of the Ross Ice Sheet from the locality on account of the lagged response of the glacier. We present a model of the Hatherton Glacier, which examines its relationship to the Ross ice sheet, using dated margin data from ice-dammed lakes. Problems in modelling are the coupling with the Darwin Glacier, the unknown bed topography and the poorly known surface mass balance, which include blue ice areas. We infer the bed topography by tuning a valley glacier model, and use this model to (i) estimate the thickness of the Last Glacial Maximum (LGM) Ross Ice Sheet; and (ii) estimate the response time of the Hatherton Glacier to changes in the Ross Sea ice sheet. The best fit of the glacier surface profile to the geological data occur if the LGM Ross Ice Sheet elevation is assumed to be 800 m higher than the present-day ice shelf surface. If the decay of the Ross Ice sheet is linear with time, the response time is of the order of several centuries. Step changes in the elevation of the Ross Ice Sheet lead to a response time around one thousand years. The dated deposits in the Hatherton Valley cannot be used directly as dates of Ross Ice Sheet grounding line retreat.

Pseudo random phase modulation signals have been shown to provide considerable stimulated Brillouin scattering (SBS) suppression in narrow linewidth Yb-doped all-fiber amplifiers. In terms of coherent beam combining, however, pseudo random signals display a linear drop in visibility; leading to pronounced drops in combining efficiencies for small path length deviations. To that end, we report a novel filtered pseudo random modulation approach for enhanced combining efficiency and coherence length performance. Here a low pass radio frequency (RF) filter is used to mitigate the PRBS high frequency components, thereby suppressing the sidelobes in the optical spectrum. This leads to an approximate Gaussian visibility function and improved coherence lengths of up to 27% in a kW class fiber amplifier (954 W). In addition, the spectral sidelobe suppression leads to concurrent SBS threshold enhancement due to a reduction in the spectral overlap between the Rayleigh reflected light and the Stokes shifted light. This reduction in the SBS seeding phenomena leads to ~10% SBS threshold improvements in a kW class fiber amplifier. Theoretical and experimental data is presented to substantiate the improved coherence length and SBS suppression. More importantly, the simultaneous nonlinear SBS suppression and coherence length benefits of the filtered PRBS approach can have a significant impact for high power, narrow linewidth, all-fiber amplifiers.

Selection of the fundamental mode of an active large mode area “ribbon” fiber laser with core dimensions of 107.8 μm by 8.3 μm was produced by a transmitting Bragg grating (TBG) in a free-space resonator. The multimode performance of the original laser was characterized to have an M2 of 11.3 with an absorbed power slope efficiency of 76%. With the TBG aligned to provide maximum diffraction efficiency for the fundamental mode, the M2 improved to 1.45 at an absorbed power slope efficiency of 54% and enhanced the brightness by 5.1 times.

The use of precast, three-sided arch culverts has become popular for new and replacement short-span bridges because of rapid construction time and minimal environmental impact on the waterway. The arching action in the top slab creates a horizontal thrust, and the surrounding fill enables lateral earth pressures to develop in the backfill based on this thrust. The lateral pressure behind the legs potentially permits the bridge to carry larger loads than it could without backfill confinement. This paper reports the results of three full-scale tests of three-sided culverts. The first test consists of a field test using an overload vehicle on a site with a newly constructed, 12.8-m clear-span, three-sided, precast arch bridge. The second specimen, an individual 6.1-m arch section, was tested in the laboratory for service-level loading in two configurations. One unrestrained configuration and one setup with steel sections simulating lateral restraint at two points along the wall were tested; additionally, the 6.1-m arch specimen was tested to failure without lateral restraint. The third specimen, an 11.0-m clear-span arch section, was tested to failure without any lateral restraint. The results of the three full-scale tests are presented and discussed. In addition, nonlinear models were calibrated with the experimental tests and then analyzed with the factored design loads to determine whether the demand, including nonlinear effects within the section, exceeded the arch section capacity.

Power scaling of high power laser resonators is limited due to several nonlinear effects. Scaling to larger mode areas can offset these effects at the cost of decreased beam quality, limiting the brightness that can be achieved from the multi-mode system. In order to improve the brightness from such multi-mode systems, we present a method of transverse mode selection utilizing volume Bragg gratings (VBGs) as an angular filter, allowing for high beam quality from large mode area laser resonators. An overview of transverse mode selection using VBGs is given, with theoretical models showing the effect of the angular selectivity of transmitting VBGs on the resonator modes. Applications of this ideology to the design of laser resonators, with cavity designs and experimental results presented for three types of multimode solid state lasers: a Nd:YVO4 laser with 1 cm cavity length and 0.8 mm diameter beam with an M 2 of 1.1, a multimode diode with diffraction limited far field divergence in the slow axis, and a ribbon fiber laser with 13 cores showing M 2 improved from 11.3 to 1.5.

We propose to use transmitting volume Bragg gratings recorded in photo-thermo-refractive glass as high efficient intracavity angular filters in order to achieve high beam quality while using large aperture active medium. The paper describes implementation of novel compact cavity design for solid state lasers, laser diodes, fiber crystal lasers and others. Keywords—Holographic volume grating, laser cavity Scaling of the pumping size in gain medium is an efficient way to increase output power, improve heat exchange and suppress nonlinear effects in different types of laser systems. Obviously, the cost of such scaling is degradation of the laser beam quality. Complex, bulk cavities or other special techniques are required in order to obtain lasing with beam quality close to diffraction limit. We propose to use transmitting volume Bragg gratings (VBGs) recorded in photothermo-refractive glass (PTR-glass) as high efficient intracavity angular filters in order to achieve high beam quality while using large aperture active medium. In comparison with standard methods of mode selection based on spatial (aperture) mode filtration, VBGs provide highly efficient mode selection in the angular space. Therefore, a very compact and simple laser cavity with extended pumping area could be created based upon such PTR glass holographic elements. The paper describes implementation of this novel laser cavity design for solid state lasers, laser diodes, fiber crystal lasers and others. While the first VBGs were recorded in PTR-glass long time ago [1], the real attention to these optical components began only when the technology allowed the fabrication of low loss and high efficiency PTR VBGs [2]. These new diffractive optical elements had high tolerance to laser radiation of up to multi kilowatt levels and triggered hundreds of publications in the area of laser applications. Today reflecting VBGs are used significantly more in laser systems in comparison with other elements from the same family. The most well-known application of such volume gratings is the narrowing and wavelength stabilization of the emission of laser diode sources [3] that are used for pumping of solid-state or fiber lasers. In comparison with reflecting gratings, transmitting VBGs have substantially narrower angular selectivity and wider spectral selectivity. Transmitting VBGs with angular selectivity of less than 50 μrad were demonstrated experimentally and this number is not the limit for our PTR glass technology. Nevertheless, up to now such a unique grating property did not find wide application in laser systems. We demonstrate experimentally the possibility to use a transmitting VBG for transverse mode selection in different types of lasers with extended pumping region. First, we designed and made a solid state laser based on Nd-doped vanadate crystal and were able to shrink the cavity length by 30 times. The implemented plain cavity had a 10 mm length. The diameter of the pumped area varied from 0.8 to 2 mm (15-94 Fresnel numbers). Without mode selection the measured M 2 exceeded 5 for pumped area with diameter of 0.8 mm. Modeling showed that the cavity losses for TEM01 mode are 2.5 times higher than the losses for TEM00 mode for wide range of transmitting VBGs with different angular selectivity. The insertion of VGB filters in the laser cavity enabled stable lasing with M 2 =1.05-1.3 for 0.8-2.0 mm pumping diameters. The slope efficiency was more than 30% for optimal parameters of the VBG filter. This number is very close to the slope efficiency of a stable semispherical cavity with 30 cm length which was used as reference. Another type of an explored laser was an external cavity strongly multi-mode broad area laser diode with 100 μm stripe. In this case, a compact (~ 3 mm) external cavity was created by off-axis scheme with a transmitting VBG as a transverse mode filter and a reflecting VBG as an output coupler. We obtained lasing with divergence close to the diffraction limit and with efficiency just 15% less than that of a free running LD. High quality emission was obtained for pumping currents which did not exceed 6-7 times the threshold. At higher currents the beam quality degraded quickly due to influences of parasitic reflections from the AR-coated mirror of the internal laser diode cavity. We could substantially expand the mentioned current interval by using the same off-axis scheme with a VBG filter for a 100 μm stripe surface emitting diode laser with a detuned grating output coupler. Additionally, VBG spatial mode selection technique was applied successfully for external cavity fiber crystal lasers and organic VECSEL. Obtained results will be discussed. [1] V.A. Borgman, L.B. Glebov, N.V. Nikonorov, G.T. Petrovskii, V.V. Savvin, A.D. Tsvetkov. Photothermal refractive effect in silicate glasses. Sov. Phys. Dokl., 34 (1989) 1011-1013. [2] L. Glebov "Photosensitive holographic glass – new approach to creation of high power lasers" Eur. J. Glass Sci. Technol. B, 48, 123–128, 2007 [3] G. Venus, A. Sevian, V. Smirnov, L. Glebov “High-brightness narrowline laser diode source with volume Bragg-grating feedback.” Proc. of SPIE Vol. 5711 (2005) , 166-176

Background: As many as 70% of veterans with chronic pain treated within the US Veterans Administration (VA) system may have posttraumatic stress disorder (PTSD), and conversely, up to 80% of those with PTSD may have pain. We describe pain experienced by US service members and veterans with symptoms of PTSD, and report on the effect of Accelerated Resolution Therapy (ART), a new, brief exposure-based therapy, on acute pain reduction secondary to treatment of symptoms of PTSD. Methods: A randomized controlled trial of ART versus an attention control (AC) regimen was conducted among 45 US service members/veterans with symptoms of combat-related PTSD. Participants received a mean of 3.7 sessions of ART. Results: Mean age was 41.0 � 12.4 years and 20% were female. Most veterans (93%) reported pain. The majority (78%) used descriptive terms indicative of neuropathic pain, with 29% reporting symptoms of a concussion or feeling dazed. Mean pre-/post-change on the Pain Outcomes Questionnaire (POQ) was � 16.9916.6 in the ART group versus � 0.7914.2 in the AC group (p � 0.0006). Among POQ subscales, treatment effects with ART were reported for pain intensity (effect size � 1.81, p � 0.006), pain-related impairment in mobility (effect size � 0.69, p � 0.01), and negative affect (effect size � 1.01, p � 0.001). Conclusions: Veterans with symptoms of combat-related PTSD have a high prevalence of significant pain, including neuropathic pain. Brief treatment of symptoms of combat-related PTSD among veterans by use of ART appears to acutely reduce concomitant pain.

Volume Bragg gratings (VBG) recorded in photo-thermo refractive glass (PTR) have high stability, and high damage threshold, allowing for many applications to the design of high power lasers. Gratings recorded in the transmitting geometry (TBG) have narrow angular selectivity, and can be used as a spatial filter in a resonator. Such gratings have previously been useful for improving the brightness of high power diodes, and increasing the beam quality in rod geometry solid state lasers. As the gratings have narrow angular selectivity, losses for higher order modes in the resonator no longer depend on the cavity length, allowing for the construction of short cavities with large mode areas. In this paper, we explore the design of short 1cm cavities using two TBGs as a spatial filter and no aperture in the cavity. The M 2 parameter as a function of pump size and angular selectivity of the TBG are explored, using pump diameters ranging from 800um to 2mm and angular selectivity ranging from 11mrad to 1.8mrad. An M 2 parameter of 1.05 is reported for an 800μm pump diameter, a 6.2mrad TBG, and a 1cm long cavity.

In order to generate high power laser radiation it is often necessary to combine multiple lasers into a single beam. The recent advances in high power spectral beam combining using multiplexed volume Bragg gratings recorded in photo-thermo-refractive glass are presented. The focus is on using multiple gratings recorded within the same volume to lower the complexity of the combining system. Combining of 420 W with 96% efficiency using a monolithic, multiplexed double grating recorded in PTR glass is demonstrated. A multiplexed quadruple grating that maintains high efficiency and good beam quality is demonstrated to pave a way for further scaling of combining channels.

Abstract The work on which this paper is based is field data and pilot testing results of variable payloads on Autonomous Surface Vehicles or Unmanned Surface Vehicles (ASVs/USVs), operating in variable industrial environments. Original field data from Multibeam echo sounder, Gyro, Motion Sensor, USBL Sonar, Passive Acoustic Monitoring for marine mammals, and ADCP data collection for ocean currents are all used to illustrate the ASV as a remote data collection platform for remote environments. By employing diesel electric propulsion and payload power strategies, the systems reviewed in this paper are capable of operation and station keeping in up to 6 knot currents, and do not require sun illumination for solar power, or favorable wind and/or sea conditions for propulsion.

Current design software (FloridaPier, Com624P) requires p-y curves to estimate the foundation lateral load resistance. Input parameters used to develop these curves can be obtained from in situ [standard penetration test (SPT) and cone penetration test (CPT)] correlations. This paper presents an evaluation of predictions using input soil parameters from SPT and CPT correlations versus field measured values. A lateral load test database consisting of 24 SPT and 6 CPT data sets was developed. The comparisons showed that four different SPT correlations for ϕ coupled with three different k-values all produce similar R-values. (R-value = measured/predicted × 100%). Therefore, little difference exists between the SPT correlation combinations, albeit the estimated k value has a greater effect on predicted deformation. Similar combinations of CPT correlations also show little effect among the commonly used correlations. SPT predictions are quite conservative at low load levels (R-values ≈ 53%) and remain conserva...

The earliest or patch stage of mycosis fungoides may present diagnostic difficulty both clinically and pathologically. The present study of the polymerase chain reaction (PCR) as a diagnostic tool in early mycosis fungoides was therefore undertaken, using a rapid PCR method for the detection of gamma- and beta-chain T-cell receptor (TCR) gene rearrangements in routine formalin-fixed, paraffin-embedded histological sections. Forty-two biopsies were studied from 26 patients with mycosis fungoides. Twenty-three skin biopsies with a clinicopathological diagnosis of early, or patch stage, mycosis fungoides were investigated. Of these, 18 (78 per cent) showed TCR-gamma or both beta- and gamma-chain TCR gene rearrangements. TCR gene rearrangements were shown in seven of the 14 plaque stage lesions (50 per cent) and also in the single case of tumour stage disease. Where gene rearrangements were identified, these were identical in all biopsies from an individual patient, irrespective of the site of the lesion, the disease stage, or the time lapse between the biopsies. The PCR is therefore a highly sensitive technique, which can be performed on routine pathological material, in cases where the diagnosis of early mycosis fungoides cannot be made with certainty on conventional histopathological and immunohistochemical grounds.

Volume Bragg gratings have been successfully used in spectr al beam combining of high po wer fiber lasers with narrow channel separationand in four channel passive coherent beam combining of fiber lasers. Future application of beam combining with kilowatt level lasers requires a more detailed understanding of how to cool the gratings without hurting beam quality. Forced air cooling blown across both surfaces of the grating is both easy and cheap, but has been avoided in the past due to concerns of how the air density fluctuations will hurt beam quality. It is now shown that forced air cooling has no adverse effect on the M 2 parameter due to density fluctuations in the air, and can efficiently cool VBG’s such that no degradation in beam quality is seen due to thermal distortions. Volume Bragg gratings are routinely made with low absorption on the level of 10 -4 cm -1 . To model grating operation for kilowatt level lasers, absorption of the studied grating was artif icially increased by 140 times. Thus the use of 80 W fiber lasers enabled imitation of 11kW beams, and the effects of forced air cooling on the beam quality were measured. Without cooling, the M

A 1cm long cavity with 800um pump diameter is built using a thin slab of Nd:YVO4. The narrow angular selectivity of a transmitting VBG is used to produce an M2 of 1.05.

Type 1 diabetes (T1D) is an autoimmune disease resulting in pancreatic b-cell lysis via reactive oxygen species (ROS), pro-inflammatory cytokines, and islet-infiltrating leukocytes. One promising treatment for T1D is islet transplantation, but its clinical application is constrained due to islet availability, adverse effects of immunosuppressants on islet function, and declining graft survival. Islet encapsulation may provide an immunoprotective barrier to aid in preserving function and curbing immune-mediated rejection post transplantation. We previously demonstrated that a cytoprotective nanothin multilayer coating consisting of tannic acid (TA), an immunomodulatory antioxidant, and poly (N-vinylpyrrolidone) (PVPON), curtailed immune responses involved in transplant rejection. We hypothesized that (PVPON/TA) coating may hinder the synthesis of redox-sensitive chemokines that recruit immune cells to sites of islet engraftment and blunt ROS-dependent cues necessary for M1 macrophage differentiation. (PVPON/TA) coatings elicited a 7-fold decrease in M1 macrophage-derived pro-inflammatory chemokines CCL5 and CXCL10, blunted M1 macrophage activation markers, and curbed diabetogenic CD4 T cell migration approximately 2-fold. Importantly, murine islet encapsulation with (PVPON/TA) material restored euglycemia in immunodeficient-diabetic mice post transplantation. Our studies demonstrate that (PVPON/TA) multilayer coatings represent a promising immunomodulatory biomaterial for islet transplantation. Future studies will evaluate the efficiency of PVPON/TA coated islets in curbing hyperglycemia by allotransplantation into diabetic rodent models.

αβ T-cell lines specific for sulfatide, an abundant myelin glycosphingolipid presented by various CD1 molecules, have been previously derived from PBMCs of patients with demyelinating diseases such as multiple sclerosis (MS) but also from healthy subjects. Using an unbiased tetramer-based MACS enrichment method to enrich for rare antigen-specific cells, we confirmed the presence of CD1d-sulfatide-specific T cells in all healthy individuals examined. Surprisingly, the great majority of fresh sulfatide-specific T cells belonged to the γδ lineage. Furthermore, these cells used the Vδ1 TCR variable segment, which is uncommon in the blood but predominates in tissues such as the gut and specifically accumulates in MS lesions. Recombinant Vδ1 TCRs from different individuals were shown to bind recombinant CD1d-sulfatide complexes in a sulfatide-specific manner. These results provide the first direct demonstration of MHC-like-restricted, antigen-specific recognition by γδ TCRs. Together with previous reports, they support the notion that human Vδ1 T cells are enriched in CD1-specific T cells and suggest that the Vδ1 T-cell population that accumulates in MS lesions might be enriched in CD1-sulfatide specific cells.

The recent development of kW fiber laser sources makes the concept of laser systems operating at power levels from tens of kilowatts up to 100 -kilowatt levels a reality. The use of volume Bragg gratings for spectral beam combining is one approach to achieve that goal. To make such systems compact, lower the complexity an d minimize the induced thermal distortions we propose and demonstrate the use of special volume Bragg elements which have several Bragg gratings written inside as combining optical components. The multiplexed volume Bragg gratings (MVBGs) were recorded in photo -thermo refractive glass and three beams with total power of 420 W were successfully combined using one MVBG. The combining efficiency was 97% and there was no significant beam quality degradation. The results demonstrated that the approach of using m ultiplexed volume Bragg gratings for spectral beam combining is an excellent extension to the current state of the art combining techniques. Especially valuable is the capability to reduce the number of optical elements in the system and while be ing able t o manage the expected thermal load when kilowatt level sources are used for beam combining. Key Words : Spectral Beam Combining, Volume Bragg Gratings, Multiplexed Volume Bragg Gratings, High Power, Fiber Lasers

[1] The “mass balance sensitivity” of a glacier provides a means for assessing its response to future warming and contribution to sea level rise. Many studies have concluded that the first-order control on mass balance sensitivity is climatic, where higher-precipitation (and less continental) glaciers are most sensitive while lower-precipitation (and more continental) glaciers are least sensitive. The Southern Alps in New Zealand experience a limited range of continentality (9–13 K) but strong gradients in precipitation (2.5–11 m a−1). Using an energy balance model applied on a regional scale we find that the central Southern Alps glaciers are very sensitive to temperature change (1.9 m w.e. a−1 K−1, with a range of −1.1 to −4.0 m w.e. a−1 K−1) and that an 82% increase in precipitation is required to offset a 1 K warming. Spatial variations in mass balance sensitivity cannot be simply explained as a function of precipitation. Topographic effects are important, and we find that debris cover reduces mass balance sensitivity. Mass balance amplitude, which takes into account debris cover, hypsometry and other topographic characteristics, is a better predictor of mass balance sensitivity than precipitation. The mass balance gradient is almost as good a predictor indicating that hypsometry is not a necessary component of sensitivity calculations. Estimating mass balance sensitivity as a function of mass balance gradient allows for parameterizations of mass balance sensitivity based on glacier inventory data. This provides a simple and robust way to assess glacier mass balance sensitivity on a global scale, which may refine future predictions of valley glacier melt and its contribution to sea level rise.

Cryptosporidium is a chlorine-resistant protozoan parasite responsible for the majority of waterborne disease outbreaks in recreational water venues in the USA. Swim diapers are commonly used by diaper-aged children participating in aquatic activities. This research was intended to evaluate disposable swim diapers for retaining 5-μm diameter polystyrene microspheres, which were used as non-infectious surrogates for Cryptosporidium oocysts. A hot tub recirculating water without a filter was used for this research. The microsphere concentration in the water was monitored at regular intervals following introduction of microspheres inside of a swim diaper while a human subject undertook normal swim/play activities. Microsphere concentrations in the bulk water showed that the majority (50–97%) of Cryptosporidium-sized particles were released from the swim diaper within 1 to 5 min regardless of the swim diaper type or configuration. After only 10 min of play, 77–100% of the microspheres had been released from all swim diapers tested. This research suggests that the swim diapers commonly used by diaper-aged children in swimming pools and other aquatic activities are of limited value in retaining Cryptosporidium-sized particles. Improved swim diaper solutions are necessary to efficiently retain pathogens and effectively safeguard public health in recreational water venues.

[1] This paper evaluates the use of field data on the spatial variability of snow water equivalent (SWE) to guide the design of distributed snow models. An extensive reanalysis of results from previous field studies in different snow environments around the world is presented, followed by an analysis of field data on spatial variability of snow collected in the headwaters of the Jollie River basin, a rugged mountain catchment in the Southern Alps of New Zealand. In addition, area-averaged simulations of SWE based on different types of spatial discretization are evaluated. Spatial variability of SWE is shaped by a range of different processes that occur across a hierarchy of spatial scales. Spatial variability at the watershed-scale is shaped by variability in near-surface meteorological fields (e.g., elevation gradients in temperature) and, provided suitable meteorological data is available, can be explicitly resolved by spatial interpolation/extrapolation. On the other hand, spatial variability of SWE at the hillslope-scale is governed by processes such as drifting, sloughing of snow off steep slopes, trapping of snow by shrubs, and the nonuniform unloading of snow by the forest canopy, which are more difficult to resolve explicitly. Subgrid probability distributions are often capable of representing the aggregate-impact of unresolved processes at the hillslope-scale, though they may not adequately capture the effects of elevation gradients. While the best modeling strategy is case-specific, the analysis in this paper provides guidance on both the suitability of several common snow modeling approaches and on the choice of parameter values in subgrid probability distributions.