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Next-generation optoelectronic devices and photonic circuitry will have to incorporate on-chip compatible nanolaser sources. Semiconductor nanowire lasers have emerged as strong candidates for integrated systems with applications ranging from ultrasensitive sensing, to data communication technologies. Despite significant advances in their fundamental aspects, the integration within scalable photonic circuitry remains challenging. Here we report on the realization of hybrid photonic devices consisting of nanowire lasers integrated with wafer-scale lithographically designed V-groove plasmonic waveguides. We present experimental evidence of the lasing emission and coupling into the propagating modes of the V-grooves, enabling on-chip routing of coherent and sub-diffraction confined light with room temperature operation. Theoretical considerations suggest that the observed lasing is enabled by a waveguide hybrid photonic-plasmonic mode. This work represents a major advance towards the realization of application-oriented photonic circuits with integrated nanolaser sources., 24 pages, 4 figures

Aluminum plasmonics is emerging as a promising platform in particular for the ultraviolet-blue spectral band. We present the experimental results of propagating channel plasmon-polaritons (CPP) waves in aluminum coated V-shaped waveguides at the short visible wavelength regime. The V-grooves are fabricated by a process involving UV-photolithography, crystallographic silicon etching, and metal deposition. Polarization measurements of coupling demonstrate a preference to the TM-aligned mode, as predicted in simulations.

When implementing Acuros XB (AXB) as a substitute for anisotropic analytic algorithm (AAA) in the Eclipse Treatment Planning System, one is faced with a dilemma of reporting either dose to medium, AXB-Dm or dose to water, AXB-Dw. To assist with decision making on selecting either AXB-Dm or AXB-Dw for dose reporting, a retrospective study of treated patients for headneck (HN), prostate, breast and lung is presented. Ten patients, previously treated using AAA plans, were selected for each site and re-planned with AXB-Dm and AXB-Dw. Re-planning was done with fixed monitor units (MU) as well as non-fixed MUs. Dose volume histograms (DVH) of targets and organs at risk (OAR), were analyzed in conjunction with ICRU-83 recommended dose reporting metrics. Additionally, comparisons of plan homogeneity indices (HI) and MUs were done to further highlight the differences between the algorithms. Results showed that, on average AAA overestimated dose to the target volume and OARs by less than 2.0 %. Comparisons between AXB-Dw and AXB-Dm, for all sites, also showed overall dose differences to be small (1.5 %). However, in non-water biological media, dose differences between AXB-Dw and AXB-Dm, as large as 4.6 % were observed. AXB-Dw also tended to have unexpectedly high 3D maximum dose values (135 % of prescription dose) for target volumes with high density materials. Homogeneity indices showed that AAA planning and optimization templates would need to be adjusted only for the HN and Lung sites. MU comparison showed insignificant differences between AXB-Dw relative to AAA and between AXB-Dw relative to AXB-Dm. However AXB-Dm MUs relative to AAA, showed an average difference of about 1.3 % signifying an underdosage by AAA. In conclusion, when dose is reported as AXB-Dw, the effect that high density structures in the PTV has on the dose distribution should be carefully considered. As the results show overall small dose differences between the algorithms, when transitioning from AAA to AXB, no significant change to existing prescription protocols is expected. As most of the clinical experience is dose-to-water based and calibration protocols and clinical trials are also dose-to-water based and there still exists uncertainties in converting CT number to medium, selecting AXB-Dw is strongly recommended.

A number of neutrophilic dermatoses are associated with malignancies and their treatment. These rarely occur together in the same patient. A Caucasian 72-year-old male was treated for acute myeloid leukemia (AML) with chemotherapy including daunorubicin and cytarabine. Within 48 hours of commencing treatment, he developed pyrexia and, two days later, disseminated non-tender pink plaques on the limbs and trunk. A skin biopsy showed a dermal interstitial infiltrate of lymphocytes, histiocytoid cells and predominantly neutrophils. This extended into the subcutis, where a neutrophilic lobular panniculitis was seen. These findings are consistent with Sweet’s syndrome. In addition, a neutrophilic and lymphocytic infiltrate was also present around eccrine coils and lower ducts. The eccrine epithelium showed squamous metaplasia with dyskeratosis and sloughing into the lumen. These latter findings are consistent with neutrophilic eccrine hidradenitis (NEH). These two histologically distinct entities form part of the neutrophilic dermatoses that have been described in oncology patients with reports of concurrent or sequential occurrence of various neutrophilic dermatoses in the same patient. Ours, however, is only the second reported case of simultaneously captured Sweet’s and NEH in the setting of AML. The most likely explanation is that of an epiphenomenon, whereby the neutrophilic infiltrate extended around the sweat glands in the context of the neutrophilic dermatosis.

Gafchromic EBT3 film is widely used for patient specific quality assurance of complex treatment plans. Film dosimetry techniques commonly involve the use of transmission scanning to produce TIFF files, which are analysed using a non-linear calibration relationship between the dose and red channel net optical density (netOD). Numerous film calibration techniques featured in the literature have not been independently verified or evaluated. A range of previously published film dosimetry techniques were re-evaluated, to identify whether these methods produce better results than the commonly-used non-linear, netOD method. EBT3 film was irradiated at calibration doses between 0 and 4000 cGy and 25 pieces of film were irradiated at 200 cGy to evaluate uniformity. The film was scanned using two different scanners: The Epson Perfection V800 and the Epson Expression 10000XL. Calibration curves, uncertainty in the fit of the curve, overall uncertainty and uniformity were calculated following the methods described by the different calibration techniques. It was found that protocols based on a conventional film dosimetry technique produced results that were accurate and uniform to within 1%, while some of the unconventional techniques produced much higher uncertainties (> 25% for some techniques). Some of the uncommon methods produced reliable results when irradiated to the standard treatment doses (

We experimentally demonstrate the interrogation of an individual Escherichia coli cell using a nanoscale plasmonic V-groove waveguide. Several different configurations were studied. The first involved the excitation of the cell in a liquid environment because it flows on top of the waveguide nanocoupler, while the obtained fluorescence is coupled into the waveguide and collected at the other nanocoupler. The other two configurations involved the positioning of the bacterium within the nanoscale waveguide and its excitation in a dry environment either directly from the top or through waveguide modes. This is achieved by taking advantage of the waveguide properties not only for light guiding but also as a mechanical tool for trapping the bacteria within the V-grooves. The obtained results are supported by a set of numerical simulations, shedding more light on the mechanism of excitation. This demonstration paves the way for the construction of an efficient bioplasmonic chip for diverse cell-based sensing applications.

Lasing emission from random cavities formed in networks of electrospun Rhodamine-doped polymer fibers is presented. Spatially resolved spectroscopy and spectral analysis prove that the observed laser emission stems from individual ring resonators randomly distributed throughout the network. These electrospun fiber lasers represent a facile and straightforward configuration for developing novel photonic devices that may advantageously utilize the network morphology.

Summary We present the case of a 54-year-old patient with renal transplant who developed unusual vascular changes on the forearm distal to a functioning arteriovenous fistula, as well as a painful ulcerated lesion on her anterior abdominal wall. We believe that the diffuse dermal angioendotheliomatosis variant of reactive angioendotheliomatosis had a role in the pathogenesis of this patient's lesions.

Design guidelines for optimizing the sensing performance of nanoimprinted second order distributed feedback dye lasers are presented. The guidelines are verified by experiments and simulations. The lasers, fabricated by UV-nanoimprint lithography into Pyrromethene doped Ormocomp thin films on glass, have their sensor sensitivity enhanced by a factor of up to five via the evaporation of a titanium dioxide (TiO2) waveguiding layer. The influence of the TiO2 layer thickness on the device sensitivity is analyzed with a simple model that accurately predicts experimentally measured wavelength shifts induced by varied superstrate refractive indices. The superstrate refractive index is additionally shown to determine which of the possible waveguiding modes dominates for lasing, indicating a method to flexibly select the polarization of the laser. The detection limit of the sensor system is further discussed, finding an optimum at 7.5· 10−6 RIU. Wavelength changes caused by dye bleaching must be taken into account for long-term measurements.

Laser & Photon. Rev. 4, No.2, 192–204 (2010) / DOI 10.1002/lpor.200810072Abstract We describe progress in the field of tuning,(re)configuration of Photonic crystal (PhC) based devices witha particular emphasis on our recent concepts and techniquesthat we have developed to tune and/or reconfigure the proper-ties of photonic crystal nanocavities. We show how our hybridapproach based on photosensitive material and tapered silicafiber can tune the (Q; ) properties of preexisting Photonic crys-tal cavities. We describe our alternative techniques to create ‘aposteriori’ spatially (re)configurable high-Q cavities in a PhCplatform. We show that optofluidics – the fusion of microfluidicswith photonic devices – offer an unquestionable added value tothe quest of a truly versatile, (re)configurable photonic crystalbased photonic chip.Schematic vision of a reconfigurable photonic crystal circuit, inthis case “microfluidically defined”.

All-optical switching devices are based on a material possessing a nonlinear optical response, enabling light to control light, and are enjoying renewed interest. Photonic crystals are a promising platform for realizing compact all-optical switches operating at very low power and integrated on an optical integrated circuit. In this review, we show that by making photonic crystals from a highly nonlinear chalcogenide glass, we have the potential to integrate a variety of active devices into a photonic chip. We describe the fabrication and testing of two-dimensional Ge33As12 Se55 chalcogenide glass photonic crystal membrane devices (waveguides and microcavities). We then demonstrate the ability to post-tune the devices using the material photosensitivity. In one proposal we hope to introduce a double-heterostructure microcavity using the photosensitivity alone.

Nitrogen-vacancy (NV) centers in diamonds are interesting due to their remarkable characteristics that are well suited to applications in quantum-information processing and magnetic field sensing, as well as representing stable fluorescent sources. Multiple NV centers in nanodiamonds (NDs) are especially useful as biological fluorophores due to their chemical neutrality, brightness and room-temperature photostability. Furthermore, NDs containing multiple NV centers also have potential in high-precision magnetic field and temperature sensing. Coupling NV centers to propagating surface plasmon polariton (SPP) modes gives a base for lab-on-a-chip sensing devices, allows enhanced fluorescence emission and collection which can further enhance the precision of NV-based sensors. Here, we investigate coupling of multiple NV centers in individual NDs to the SPP modes supported by silver surfaces protected by thin dielectric layers and by gold V-grooves (VGs) produced via the self-terminated silicon etching. In the first case, we concentrate on monitoring differences in fluorescence spectra obtained from a source ND, which is illuminated by a pump laser, and from a scattering ND illuminated only by the fluorescence-excited SPP radiation. In the second case, we observe changes in the average NV lifetime when the same ND is characterized outside and inside a VG. Fluorescence emission from the VG terminations is also observed, which confirms the NV coupling to the VG-supported SPP modes., 22 pages, 13 figures

We experimentally demonstrate coupling of fluorescent light from a single bacterium into a plasmonic V-groove waveguide mode. This result is the first step in the construction of an efficient bioplasmonic chip for diverse sensing applications.

Electrohydrodynamic jetting is used to manufacture dye-doped polymer fiber resonators. We present comb-like laser emission from different polymer/dye combinations and report the use of these structures as sensitive detection of ethanol and methanol.

We describe the fabrication of low-loss, highly flexible silica fibre nanowires which are used to characterise chalcogenide two-dimensional photonic crystal waveguide circuits and nanocavities. Localised coupling is achieved in good agreement with theory.

Acral pseudolymphomatous angiokeratoma of children (APACHE) is a condition that was first described in 1990 in a group of children, but has since been described in adults. We present the cases of identical twin patients aged 40 years. The first brother presented with an 8-year history of itchy lesions over the left ankle and the insteps of both feet. After a diagnostic biopsy, he was treated with potent steroids under occlusion for 8 weeks, which resulted in flattening of the lesions and resolution of the pruritus. The second twin had a 20-year history of a very similar presentation but the lesions were less pronounced; he chose not to have treatment. No other family members were affected. Skin biopsies from both patients showed similar changes. Within an overall hyperkeratotic and acanthotic epidermis, there were focal areas of lichenoid change and epidermal thinning. Beneath these areas, there was oedema and nodular aggregates of dense inflammatory cell infiltrate, predominantly lymphocytic infiltrate. APACHE has not been previously described in twins.

An all-polymer photonic crystal slab sensor is presented, and shown to exhibit narrow resonant reflection with a FWHM of less than 1 nm and a sensitivity of 31 nm/RIU when sensing media with refractive indices around that of water. This results in a detection limit of 4.5x10-6 RIU when measured in conjunction with a spectrometer of 12 pm/pixel resolution. The device is a two-layer structure, composed of a low refractive index polymer with a periodically modulated surface height, covered with a smooth upper-surface high refractive index inorganic-organic hybrid polymer modified with ZrO2-based nanoparticles. Furthermore, it is fabricated using inexpensive vacuum-less techniques involving only UV nanoreplication and polymer spin-casting, and is thus well suited for single-use biological and refractive index sensing applications.

Microstructured optical fibres (MOFs) have attracted much interest in recent times, due to their unique waveguiding properties that are vastly different from those of conventional step-index fibres. Tapering of these MOFs promises to significantly extend and enhance their capabilities. In this paper, we review the fabrication and characterisation techniques of these fibre tapers, and explore their fundamental waveguiding properties and potential applications. We fabricate photonic crystal fibre tapers without collapsing the air-holes, and confirm this with a non-invasive probing technique that enables the characterisation of the internal microstructure along the taper. We then describe the fundamental property of such tapers associated with the leakage of the core mode that leads to long-wavelength loss, influencing the operational bandwidth of these tapers. We also revisit the waveguiding properties in another form of tapered MOF photonic wires, which transition through waveguiding regimes associated with how strongly the mode is isolated from the external environment. We explore these regimes as a potential basis for evanescent field sensing applications, in which we can take advantage of air-hole collapse as an extra dimension to these photonic wires.

Objective: To evaluate the association of parental history of atopic disease with childhood atopic dermatitis, and to examine the relative strength of associations with maternal and paternal disease. Design: Mothers were recruited to the Avon longitudinal study of parents and children (ALSPAC) from the eighth week of pregnancy. Before parturition, both parents were asked, separately, to report their lifetime history of eczema, asthma, and hayfever. Parents reported symptoms of atopic dermatitis in their children at ages 6, 18, 30, and 42 months. Results: Of 8530 children with complete information on rash at ages 6, 18, 30, and 42 months, 7969 had complete information on maternal atopic disease and 5658 on maternal and paternal atopic disease. There was a strong association between parental eczema and childhood atopic dermatitis: odds ratio 1.69 (95% confidence interval, 1.47 to 1.95) for maternal eczema only, 1.74 (1.44 to 2.09) for paternal eczema only, and 2.72 (2.09 to 3.53) for eczema in both parents. Associations with parental asthma or hayfever were attenuated after controlling for parental eczema. There was no evidence that associations with maternal atopy were stronger than with paternal. Conclusions: Associations between parents’ atopic disease and the risk of atopic dermatitis in offspring vary according to the type of atopic disease in the parents, but not according to parental sex. These results are at variance with previous studies reporting stronger associations with maternal than paternal atopy, and suggest that there is no “parent-of-origin” effect in atopic dermatitis. Parental eczema may be a better marker than parental asthma/hayfever in predisposing to childhood eczema.

We report a case of idiopathic hypereosinophilic syndrome (HES) presenting with cutaneous infarction and subsequent extensive deep vein thrombosis. The eosinophilia improved dramatically with systemic corticosteroid therapy. A variety of skin disorders have been associated with HES, although there are no previous reports of HES associated with cutaneous infarction. HES is a rare disorder characterized by a sustained overproduction of eosinophils and multisystem disease. The aetiology of the eosinophilia remains uncertain but clonal populations of abnormal T-cells producing interleukin 5 may be implicated.

Dye-doped polymer fiber networks fabricated with electrospinning exhibit comb-like laser emission. We identify randomly distributed ring resonators being responsible for lasing emission by making use of spatially resolved spectroscopy. Numerical simulations confirm this result quantitatively.

The aim of this study was to compare the efficacy and tolerability of twice-daily vs. once-daily regimes of dithranol (anthralin) in Lassar's paste. Over a 4-year period, 61 inpatients with stable plaque psoriasis gave informed consent and entered a randomized controlled trial, having twice or once-daily application of dithranol in Lassar's paste as part of otherwise standard Ingram's regime. Primary outcome measurements were time required in hospital, nursing time, changes in total body surface area affected by psoriasis and thickness of a target plaque and in some patients, an assessment of the recurrence of psoriasis. Doctors were blinded as to the regime being used. At entry, mean patient age, lesional surface area and target plaque thickness were comparable in both groups and no patient had received systemic therapy in the preceding 3 months. Forty-two patients completed the study, two (11%) in the twice-daily group withdrawing due to skin irritation or 'burning'. Mean lesional surface area and target plaque thickness were similar in both groups at hospital discharge. Mean (+/- SD) time spent in hospital was not significantly different in each group, being 13.3 (+/- 6.2) days and 13.9 (+/- 4.5) days for the twice-daily and once-daily groups, respectively (P = 0.36). Duration of hospitalization did not correlate with surface area or plaque thickness on admission. Mean (+/- SD) nursing time spent on treatment was significantly greater in the twice-daily group, at 0.82 (+/- 0.33) hours per day compared with 0.51(+/- 0.25) hours per day in the once-daily group. Relapse rate at 6 months was not different between the two groups.

A sensing approach based on laser emissionfrom polymer fiber networks is presented. Poly(methyl methacrylate) (PMMA) fibers doped with a laser dye are fabricated by electrospinning. They form random loop resonators, which show laser emission upon optical pumping. The shift of the spectral position of the narrow lasing modes upon uptake of alcohol vapors (model vapors are methanol and ethanol) serves as sensor signal. Thus, the high sensitivity related to the spectral line shifts of cavity-based transducers can be combined with the fiber's large surface to volume ratio. The resulting optical sensors feature excellent sensing performance due to the large overlap (more than 80%) of light field and transducer. The shift of the laser modes results from the swelling of the polymer when exposed to solvent vapors. Due to distinctly different diffusion coefficients in polymers, the uptake dynamics reflected in the transient shift of the lasing peaks can be used to discriminate ethanol and methanol vapor in mixtures of them. The sensing mechanism is expected to be applicable to other solvent vapors that cause polymer swelling.

CD56+ lymphomas derived from natural killer (NK) cell lineage are rarely encountered in Western populations and their clinical and pathological features have not been fully defined. The majority of reported cases are lymphomas of the nasal cavity, which are most commonly seen in Asia. A subtype of CD56+ lymphoma has recently been described (blastoid NK-cell lymphoma) which characteristically presents in older patients with cutaneous infiltrates and disease at other nodal and extranodal sites. We describe a case that correlates well with the clinicopathological features of blastoid NK-cell lymphoma. An unusual feature in our patient was that the cutaneous features of the lymphoma showed complete resolution shortly following commencement of oral steroid therapy.

Objective To evaluate a novel coconut-derived emulsion (CDE) shampoo against head lice infestation in children. Design A school trial in which pupils were treated on days 0 and 7 and checked on days 8 and 15 and a family trial where product was applied by parents three times in 2 weeks or used as a cosmetic shampoo and checked on days 14 and days 70. Setting UK schools in Bristol and Western-super-Mare and families in Northern Somerset. Main outcome measure Numbers of children free from infestation after treatment. Results In the school trial, percentage cures at day 8 were 14% (permethrin, n = 7) and 61% (CDE, n = 37). In the family trial where all family members were treated, cure rate was 96% (n = 28), and if the shampoo was subsequently used as a cosmetic shampoo, only 1 of 12 children became re-infested after 10 weeks. Conclusion CDE shampoo is a novel effective method of controlling head lice and used after treatment as a cosmetic shampoo can aid in the reduction of re-infestation.

We demonstrate that high-Q nanocavity mode in 2D photonic crystal made in highly nonlinear chalcogenide glass can be excited using evanescent coupling from a tapered optical flbre. This scheme provides a promising platform to realize low power integrated all- optical switching and logic functions. The key to all-optical processing is the ability to enhance nonlinear efiects. One approach is based on developing optical conflgurations in which nonlinear efiects in a weakly nonlinear material are enhanced by reducing the mode size and increasing the intensity of the light wave. 2D photonic crystal (PhC) membranes are expected to play a key role in this context. It has been shown that ultra small and high quality factor Q can be created by introducing a carefully designed defect in the PhC (1). Following those advances, there have been predictions of the possibility of light switching light using nonlinear compact PhC microcavities operating at power levels of only a few mW (2,3). Chalcogenide glasses are attractive materials for all-optical signal processing. These glasses are composed of heavy elements including the chalcogens: S, Se and Te. The refractive index of chalcogenide is high, typically between 2.4 and 3.0 allowing 2D PhC slab to be created. Absorption losses are low over a wide wavelength range (near- to mid-infrared). Chalcogenide glasses possess a relatively large third-order optical nonlinearity (100{1000 times that of silica), and low two- photon absorption. In addition to reducing the switching power requirements, the pure Kerr-like nonlinearities ofier the potential for near instantaneous response times (< 100fs) and are only limited by the resonator Q-factor. Using chalcogenide glasses to fabricate a 2D PhC nanocavity which conflnes light at the wave- length scale and thus enhances the nonlinear light-material interaction provides the essential in- gredients for all-optical ultra-fast switching at low powers. It is well known that such cavities can exhibit optical bistability at incident powers that scale as the inverse square of the cavity's quality factor: 1/Q 2 . It is also well known that the minimum fractional nonlinear change in the refractive index, -n/n, needed to operate the device has to be greater than the inverse of the cavity's quality factor 1/Q. A common characteristic with glasses is that an upper bound exists on the nonlinear index change, -n, of a few 10 i4 . This implies that a minimum Q-factor exists of about 5,000 in order to observe a nonlinear switching. In addition, a strong resonance depth is required to obtain high contrast between the two switching states. Using PhC nanocavities ofier the advantage to strongly localize the mode in a small volume while limiting radiation losses through careful design (Fig. 1).

We demonstrate the highly efficient (>50%) conversion of freely propagating light to channel plasmon-polaritons (CPPs) in gold V-groove waveguides using compact 1.6 mu m long waveguide-termination coupling mirrors. Our straightforward fabrication process, involving UV-lithography and crystallographic silicon etching, forms the coupling mirrors innately and ensures exceptional-quality, wafer-scale device production. We tailor the V-shaped profiles by thermal silicon oxidation in order to shift initially wedge-located modes downward into the V-grooves, resulting in well-confined CPPs suitable for nanophotonic applications. We demonstrate the highly efficient (>50%) conversion of freely propagating light to channel plasmon-polaritons (CPPs) in gold V-groove waveguides using compact 1.6 mu m long waveguide-termination coupling mirrors. Our straightforward fabrication process, involving UV-lithography and crystallographic silicon etching, forms the coupling mirrors innately and ensures exceptional-quality, wafer-scale device production. We tailor the V-shaped profiles by thermal silicon oxidation in order to shift initially wedge-located modes downward into the V-grooves, resulting in well-confined CPPs suitable for nanophotonic applications.

We demonstrate >50% conversion of light to V-groove channel plasmon-polaritons (CPPs) via compact waveguide-termination mirrors. Devices are fabricated using UV-lithography and crystallographic silicon etching. The V-shape is tailored by thermal oxidation to support confined CPPs.

The tricyclic antidepressant, doxepin, is known to have H1 and H2 antihistaminic effects. Recently, 5% doxepin cream has been marketed in the U.S.A. for treatment of eczematous dermatoses. We investigated the effects of topical doxepin treatment on histamine-, substance P- and prostaglandin E2- (PGE2) induced responses in the skin of normal and atopic subjects. We compared the effects of topical doxepin with those of the oral antihistamine terfenadine. The weal volume and flare area responses to histamine were significantly reduced by treatment with topical doxepin or oral terfenadine in both normal and atopic subjects (P < 0.05). The mean +/- SEM percentage reduction in flare area for 10 micrograms/site of histamine in non-atopics and atopics was 48 +/- 8% and 60 +/- 17% with terfenadine, and 54 +/- 12% and 81 +/- 4% with topical doxepin, respectively. The mean percentage reduction in weal volume for the same dose of histamine in non-atopics and atopics was 70 +/- 9% and 63 +/- 16% with terfenadine, and 96 +/- 2% and 89 +/- 6% with topical doxepin, respectively. The flare but not the weal response to substance P was inhibited by both treatments in all subjects (P < 0.05). The mean +/- SEM percentage reduction in flare area for 200 pmol/site of substance P in non-atopics and atopics was 53 +/- 10% and 73 +/- 4% with terfenadine, and 74 +/- 7% and 75 +/- 4% with topical doxepin, respectively. The cutaneous responses to PGE2 were not affected by either drug. The inhibitory effects of doxepin were as great as those of terfenadine, and doxepin had a significantly greater effect than terfenadine in inhibiting the weal response to histamine and flare response to substance P in normal volunteers (P < 0.05). There was no significant difference between atopics and non-atopics in the percentage reduction of cutaneous responses by oral terfenadine or topical doxepin. Marked sedation occurred in three of the first 10 subjects treated with topical doxepin, necessitating a reduction in dosage for the remaining six subjects. In summary, topical doxepin was as effective as, and sometimes more effective than, a standard dose of oral terfenadine in the inhibition of histamine-induced and axon-reflex-mediated cutaneous responses. The marked sedative effect may limit its clinical use in some patients.

In this work, a simple approach to tailor the intensity distribution of CPP modes in metallic V-grooves is demonstrated by modifying the waveguide cross-section.The procedure involves a thermal oxidation of V-grooves formed in crystallographic planes of silicon that enables sidewall and vertex angle adjustment.

A transparent, fully integrated electrically modulated projection technique is presented based on light guiding through a thin liquid crystal layer covering sub-wavelength gratings. The reported device operates at 10 V with response times of 4.5 ms. Analysis of the liquid crystal alignment shows that director-reorientation occurs over timescales on the order of 90 µs close to the grating surface. The technology is suitable for next generation heads-up-displays and reconfigurable multilayer photonic integrated circuits.

International audience; Enhanced control of diffraction through transparent substrates is achieved via disordered gratings in a silica sol-gel film. Tailoring the degree of disorder allows tuning of the diffractive behavior from discrete orders into broad distributions over large angular range. Gratings of optical quality are formed by silica sol-gel nanoimprint lithography and an optical setup for the measurement of continuous diffraction patterns is presented. Sound agreement is found between measurements and simulation, validating both the approach for redirection of light and the fabrication process. The disordered gratings are presented in the context of improved interior daylighting and may furthermore be suited to a wide variety of applications where controlled angular redirection of light is desired.

Serial plasma samples were collected after administration of 13 intravenous doses of phenytoin to 11 patients with head injury; 5 to patients who had been receiving enteral feeds for less than 5 days (group 1), and 8 to patients who had been receiving enteral feeds for longer than 5 days (group 2). Average plasma phenytoin concentrations were higher in group 1 than in group 2 (p=0.003). The median intravenous study dose was the same (300 mg) in both groups (p=0.1 7). Group 2 received slightly higher doses expressed as mg/kg (median of 5.45 mg/kg compared to 4.29 mg/kg in group 1, p=0.21). Phenytoin was more rapidly eliminated following intravenous dosing in patients receiving long-term enteral feeding.Vmax was higher in group 2 than in group 1 (medians, 709versus 394 mg/day) andKm smaller (medians, 2.5versus 3.9 mg/l), but volume of distribution was similar in both groups (p=0.88). The kinetic parameters of phenytoin in group 1 were similar to previously published population pharmacokinetic parameters. In order to maintain phenytoin concentrations adequate for seizure prophylaxis in patients receiving longterm enteral feeding it would be advisable to decrease the dosing interval as well as increasing the phenytoin dose when the drug is administered intravenously.

We facilitate photonic crystal lasers to sense gases via an additional swelling polymer film. We describe the transduction transfer function and experimentally demonstrate an enhanced ethanol vapor sensitivity over 15 dB with low humidity crosstalk.

We introduce visible light optical gratings to surface plasmon V-groove waveguides. Gradient e-beam dosage onto silicon stamp enables structuring V-grooves of varying depth. Nanoimprint lithography maintains a Λ=265 nm corrugation for gold surface devices.

Optically pumped polymer photonic crystal band-edge dye lasers are presented. The photonic crystal is a rectangular lattice providing laser feedback as well as an optical resonance for the pump light. The lasers are defined in a thin film of photodefinable Ormocore hybrid polymer, doped with the laser dye Pyrromethene 597. A compact frequency doubled Nd:YAG laser (352 nm, 5 ns pulses) is used to pump the lasers from above the chip. The laser devices are 450 nm thick slab waveguides with a rectangular lattice of 100 nm deep air holes imprinted into the surface. The 2-dimensional rectangular lattice is described by two orthogonal unit vectors of length a and b, defining the ΓP and ΓX directions. The frequency of the laser can be tuned via the lattice constant a (187 nm - 215 nm) while pump light is resonantly coupled into the laser from an angle (θ) depending on the lattice constant b (355 nm). The lasers are fabricated in parallel on a 10 cm diameter wafer by combined nanoimprint and photolithography (CNP). CNP relies on a UV transparent quartz nanoimprint stamp with an integrated metal shadow mask. In the CNP process the photonic crystal is formed by mechanical deformation (imprinting) while the larger features are defined by UV exposure through the combined mask/mold.

Introducing a phase-shift in nanoimprinted polymer dye lasers is shown to increase the probability of single mode lasing from 19% to 99%. Low-index lasers with only one longitudinal mode are thus superior to band-edge lasers.

We present a dye-doped liquid crystal laser using a photonic crystal cavity. An applied electric field to the liquid crystal provides wavelength tunability. The photonic crystal enhances resonant interaction with the gain medium.

We report reconfigurable optofluidic photonic crystal components in silicon-based membranes by controllably infiltrating and removing fluid from holes of the photonic crystal lattice. Systematic characterizations of our fluidically defined microcavities are presented, corresponding with the capability to increase or decrease the span of the fluid-filled regions and thus alter their optical properties. We show initial images of single-pore fluid infiltration for holes of diameter 265 nm. Furthermore, the infiltration process may employ a large range of optical fluids, adding more flexibility to engineer device functionality. We discuss the great potential offered by this optofluidic scheme for integrated optofluidic circuits, sensing, fluorescence and plasmonic applications.

We present a principle for the temperature stabilization of photonic crystal (PhC) cavities based on optofluidics. We introduce an analytic method enabling a specific mode of a cavity to be made wavelength insensitive to changes in ambient temperature. Using this analysis, we experimentally demonstrate a PhC cavity with a quality factor of Q≈15 000 that exhibits a temperature-independent resonance. Temperature-stable cavities constitute a major building block in the development of a large suite of applications from high-sensitivity sensor systems for chemical and biomedical applications to microlasers, optical filters, and switches.

We demonstrate a direct, single measurement technique for characterizing the dispersion of a photonic crystal waveguide (PCWG) using a tapered fiber evanescent coupling method. A highly curved fiber taper is used to probe the Fabry-Pérot spectrum of a closed PCWG over a broad k-space range, and from this measurement the dispersive properties of the waveguide can be found. Waveguide propagation losses can also be estimated from measurements of closed waveguides with different lengths. The validity of this method is demonstrated by comparing the results obtained on a 'W1' PCWG in chalcogenide glass with numerical simulation. © 2008 Optical Society of America.

We demonstrate a photonic crystal (PC) cavity formed post-fabrication by locally modifying the refractive index of a chalcogenide PC by using the photosensitivity of the chalcogenide glass.

We demonstrate reconfigurable microfluidic photonic crystal double-heterostructure cavities by local fluid infiltration of select air holes. Properties of the microfluidic cavities are experimentally studied by evanescent coupling and analyzed by numerical simulations.