Regression analysis of protoporphyrin IX measurements obtained during dermatological photodynamic therapy (article)

This is the final version. Available from MDPI via the DOI in this record.The dataset associated with this article is located in ORE at: https://doi.org/10.24378/exe.1103Photodynamic therapy (PDT) is a light activated drug therapy that can be used to treat a number of dermatological cancers and precancers. Improvement of efficacy is required to widen its application. Clinical protoporphyrin IX (PpIX) fluorescence data were obtained using a pre-validated, non-invasive imaging system during routine methyl aminolevulinate (MAL)-PDT treatment of 172 patients with licensed dermatological indications (37.2% actinic keratosis, 27.3% superficial basal cell carcinoma and 35.5% Bowen's disease). Linear and logistic regressions were employed to model any relationships between variables that may have affected PpIX accumulation and/or PpIX photobleaching during irradiation and thus clinical outcome at three months. Patient age was found to be associated with lower PpIX accumulation/photobleaching, however only a reduction in PpIX photobleaching appeared to consistently adversely affect treatment efficacy. Clinical clearance was reduced in lesions located on the limbs, hands and feet with lower PpIX accumulation and subsequent photobleaching adversely affecting the outcome achieved. If air cooling pain relief was employed during light irradiation, PpIX photobleaching was lower and this resulted in an approximate three-fold reduction in the likelihood of achieving clinical clearance. PpIX photobleaching during the first treatment was concluded to be an excellent predictor of clinical outcome across all lesion types.Duchy Health Charity Ltd.Killing Cancer, U

Optical carrier wave shocking: detection and dispersion

Carrier wave shocking is studied using the Pseudo-Spectral Spatial Domain (PSSD) technique. We describe the shock detection diagnostics necessary for this numerical study, and verify them against theoretical shocking predictions for the dispersionless case. These predictions show Carrier Envelope Phase (CEP) and pulse bandwidth sensitivity in the single-cycle regime. The flexible dispersion management offered by PSSD enables us to independently control the linear and nonlinear dispersion. Customized dispersion profiles allow us to analyze the development of both carrier self-steepening and shocks. The results exhibit a marked asymmetry between normal and anomalous dispersion, both in the limits of the shocking regime and in the (near) shocked pulse waveforms. Combining these insights, we offer some suggestions on how carrier shocking (or at least extreme self-steepening) might be realised experimentally.Comment: 9 page

THE INFLUENCE OF SALT MARSH FUCOID ALGAE (ECADS) ON SEDIMENT DYNAMICS OF NORTHWEST ATLANTIC MARSHES

Resilience is currently a key theme within salt marsh ecological studies. Understanding the factors that affect salt marsh accretion and elevation gains are of paramount importance if management of these ecosystems is to be successful under increasing synergistic stresses of storm surge, inundation period, and eutrophication. We present the results of salt marsh fucoid algae (ecads) removal experiments on Spartina alterniflora abundance, production and decomposition and the sedimentary dynamics of two marshes on Cape Cod, Massachusetts. The presence of the thick layer of marsh fucoids had a significant and positive influence on sediment deposition, accretion, concentration of water column particulates, while it inhibited water flow. Decomposition rates of Spartina alterniflora in the field were significantly higher under the fucoid macroalgae layer, and, in lab experiments, S. alterniflora seedlings added more leaves when the marsh fucoids were present. In contrast, fucoids caused a significant decrease in S. alterniflora seedlings’ survival in the field. We found that marsh fucoids are stable despite not being attached to any substrate, and field surveys revealed a relatively widespread, but not ubiquitous, distribution along outer Cape Cod. Salt marsh fucoid algae directly and substantially contribute to salt marsh sediment elevation gain, yet their potential inhibitory effects on colonizing S. alterniflora may counteract some of their overall contributions to salt marsh persistence and resilience

Pearling: stroke segmentation with crusted pearl strings

We introduce a novel segmentation technique, called Pearling, for the semi-automatic extraction of idealized models of networks of strokes (variable width curves) in images. These networks may for example represent roads in an aerial photograph, vessels in a medical scan, or strokes in a drawing. The operator seeds the process by selecting representative areas of good (stroke interior) and bad colors. Then, the operator may either provide a rough trace through a particular path in the stroke graph or simply pick a starting point (seed) on a stroke and a direction of growth. Pearling computes in realtime the centerlines of the strokes, the bifurcations, and the thickness function along each stroke, hence producing a purified medial axis transform of a desired portion of the stroke graph. No prior segmentation or thresholding is required. Simple gestures may be used to trim or extend the selection or to add branches. The realtime performance and reliability of Pearling results from a novel disk-sampling approach, which traces the strokes by optimizing the positions and radii of a discrete series of disks (pearls) along the stroke. A continuous model is defined through subdivision. By design, the idealized pearl string model is slightly wider than necessary to ensure that it contains the stroke boundary. A narrower core model that fits inside the stroke is computed simultaneously. The difference between the pearl string and its core contains the boundary of the stroke and may be used to capture, compress, visualize, or analyze the raw image data along the stroke boundary

Phenological characteristics of global coccolithophore blooms

Coccolithophores are recognized as having a significant influence on the global carbon cycle through the production and export of calcium carbonate (often referred to as particulate inorganic carbon or PIC). Using remotely sensed PIC and chlorophyll data, we investigate the seasonal dynamics of coccolithophores relative to a mixed phytoplankton community. Seasonal variability in PIC, here considered to indicate changes in coccolithophore biomass, is identified across much of the global ocean. Blooms, which typically start in February–March in the low-latitude (~30°) Northern Hemisphere and last for ~6–7 months, get progressively later (April–May) and shorter (3–4 months) moving poleward. A similar pattern is observed in the Southern Hemisphere, where blooms that generally begin around August–September in the lower latitudes and which last for ~8 months get later and shorter with increasing latitude. It has previously been considered that phytoplankton blooms consist of a sequential succession of blooms of individual phytoplankton types. Comparison of PIC and chlorophyll peak dates suggests instead that in many open ocean regions, blooms of coccolithophores and other phytoplankton can co-occur, conflicting with the traditional view of species succession that is thought to take place in temperate regions such as the North Atlantic

A phase II, multicentre, UK study of vinorelbine in advanced breast cancer.

Thirty-four evaluable patients were treated with vinorelbine, a novel, semisynthetic vinca alkaloid, as first-line chemotherapy for advanced breast cancer. They received vinorelbine 25 mg m-2 i.v. given weekly for a maximum of 16 cycles. Two patients achieved a complete remission and 15 a partial remission, giving a response rate of 17/34 (50%; 95% CI of 34-66%); median response duration was 5.8 months. The median progression-free interval was 4.4 months and median survival 9.9 months. Treatment was generally well tolerated. Fatigue was the most common side-effect. The main reason for dose adjustments was myelosuppression; 68% of patients had WHO grade 3 or 4 neutropenia and there was one death attributed to neutropenic sepsis. Nausea/vomiting and neuropathy were mild and alopecia was uncommon. This study confirms vinorelbine as a highly active, well-tolerated agent in advanced breast cancer worthy of evaluation in combination chemotherapy regimens

Local implicit modeling of blood vessels for interactive simulation

International audienceIn the context of computer-based simulation, contact management requires an accurate, smooth, but still efficient surface model for the blood vessels. A new implicit model is proposed, consisting of a tree of local implicit surfaces generated by skeletons ({\em blobby models}). The surface is reconstructed from data points by minimizing an energy, alternating with an original blob selection and subdivision scheme. The reconstructed models are very efficient for simulation and were shown to provide a sub-voxel approximation of the vessel surface on 5 patients

Contrasting effects of temperature and winter mixing on the seasonal and inter-annual variability of the carbonate system in the Northeast Atlantic Ocean

Future climate change as a result of increasing atmospheric CO2 concentrations is expected to strongly affect the oceans, with shallower winter mixing and consequent reduction in primary production and oceanic carbon drawdown in low and mid-latitudinal oceanic regions. Here we test this hypothesis by examining the effects of cold and warm winters on the carbonate system in the surface waters of the Northeast Atlantic Ocean for the period between 2005 and 2007. Monthly observations were made between the English Channel and the Bay of Biscay using a ship of opportunity program. During the colder winter of 2005/2006, the maximum depth of the mixed layer reached up to 650 m in the Bay of Biscay, whilst during the warmer (by 2.6 a± 0.5 a°C) winter of 2006/2007 the mixed layer depth reached only 300 m. The inter-annual differences in late winter concentrations of nitrate (2.8 ± 1.1 μmol l−1) and dissolved inorganic carbon (22 a± 6 μmol kg−1, with higher concentrations at the end of the colder winter (2005/2006), led to differences in the dissolved oxygen anomaly and the chlorophyll <i>α</i>-fluorescence data for the subsequent growing season. In contrast to model predictions, the calculated air-sea CO2 fluxes (ranging from +3.7 to ĝ̂'4.8 mmol mĝ̂'2 d−1) showed an increased oceanic CO2 uptake in the Bay of Biscay following the warmer winter of 2006/2007 associated with wind speed and sea surface temperature differences. ©Author(s) 2010. CC Attribution 3.0 License