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Morbidity and impacts on quality of life remain significant issues following oesophagectomy for oesophageal cancer. This paper reviews and weighs the current evidence both in favour of and against the adoption of an organ-preserving approach in patients with a complete clinical response to neoadjuvant therapy.

Anal fissure is the most common cause of severe anorectal pain in adults, contributing significantly to coloproctology workloads. There are a wide variety of management options available, including topical nitrites, calcium channel blockers, botulinum toxin injection and sphincterotomy. The aim of this study was to review current options for the treatment of chronic anal fissure.A comprehensive search identifying randomized controlled trials comparing treatment options for anal fissure published between January 2000 and February 2020 was performed. The primary outcome assessed was healing at 8 weeks post commencing treatment. Secondary outcomes included recurrence, intolerance of treatment and complications.A total of 2822 studies were identified. After removal of duplicates and non-relevant studies, we identified nine randomized controlled trials which met pre-defined criteria. There was a total of 775 patients. At 8 weeks, healing rates were 95.13% in those treated with sphincterotomy, 66.7% in the botulinum toxin group, 63.8% in the nitrate group, 52.3% for topical diltiazem and 50% for topical minoxidil. Recurrence was highest amongst those treated with botulinum toxin injection (41.7%) and lowest for sphincterotomy (6.9%). Although the absolute number is low, there was a risk of permanent incontinence with sphincterotomy.This review of the randomized control data demonstrates that healing was significantly higher amongst those treated with sphincterotomy versus more conservative modalities. Topical nitrites had similar outcomes to botulinum toxin injection but were poorly tolerated in comparison to other treatments. The benefit of sphincterotomy was at a cost of increased complications, notably permanent incontinence.

An investigation is reported in the use of time-resolved laser-induced breakdown spectroscopy (LIBS) for mineral assaying applications. LIBS has potential for the rapid on-line determination of the major and minor constituents of mineral drill core samples. In this work a Q-switched Nd:YAG laser is used to test as-received lengths of drill core, with remote LIBS signal acquisition via a bare optical fiber bundle coupled to a spectrometer. A novel normalization scheme, based on integrating the total plasma emission, is demonstrated as a method for correction of signal variations due to the uneven surface geometry of rock. Averaged intensities of atomic emission for the elements Cr, Cu, Fe, Mn, and Ni show good linear correlations, with coefficients of R2 = 0.92–0.99, against laboratory assay values. Limitations in the comparison of the results of surface analysis to bulk compositions are discussed, with emphasis on mining applications of LIBS.

An investigation was made into the interaction of Q-switched Nd: glass laser pulses, with energies of 5–100 J and intensities in the range of 1–15 GW cm−2, with thin slab samples of basalt, in a geometry in which the laser–matter interaction was enhanced by confining the laser-induced plasma and vapor against the rock surface with a thin water layer. The high pressure generated during expansion of the ablated material produced a shock wave which traveled into the rock. On basalt samples of thicknesses of up to 18 mm, reflection of the shock wave at the rear surface of the sample caused a thin rock layer to be spalled. Examination of the structure within the interior of the rock after laser exposure revealed extensive grain disruption near to the laser spot, due to the shock-wave passage. Rock specimens of thickness 50 mm were tested via Vickers hardness microindenter. The laser exposure was shown to produce a hardness decrease within the rock which was up to 50%, and extended to depths of 25 mm beneath the target position. An empirical model accounting for shock-wave formation and propagation was developed and compared to the experimental results.

We report an experimental investigation of absorption, fluorescence, and nonlinear absorption in a platinum-ethynyl complex. We have observed strong singlet absorption at 355 nm, and a weaker triplet absorption at 520 nm. Photoluminescence measurements show a fluorescence band at 400 nm and a phosphorescence band at 520 nm. Pump–probe nonlinear absorption measurements confirmed that S0→T1 followed by excited triplet-state absorption corresponds to the dominant excitation path in the region between 513 and 532 nm.

In patients with non-metastatic but inoperable non-small cell lung cancer that is locally too extensive for radical radiotherapy (RT), but who have good performance status, it is important to determine whether thoracic RT should be the minimum that is required to palliate thoracic symptoms or whether treatment should be more intensive, with the aim of prolonging survival. A total of 509 such patients from 11 centres in the UK between November 1989 and October 1992 were admitted to a trial comparing palliative versus more intensive RT with respect to survival and quality of life. They were allocated at random to receive thoracic RT with either 17 Gy in two fractions (F2) 1 week apart (255 patients) or 39 Gy in 13 fractions (F13) 5 days per week (254 patients). Survival was better in the F13 group, the median survival periods being 7 months in the F2 group compared with 9 months in the F13 group, and the survival rates 31% and 36% at one year and 9% and 12% at 2 years, respectively (hazard ratio=0.82; 95% CI 0.69–0.99). There was a suggestion of a trend towards greater benefit in fitter patients. Metastases appeared earlier in the F2 group. As recorded by patients using the Rotterdam Symptom Checklist, the commonest symptoms on admission were cough, shortness of breath, tiredness, lack of energy, worrying and chest pain. These were more rapidly palliated by the F2 regimen. Psychological distress was generally lower in the F13 group. Three patients (two F13, one F2) exhibited evidence of myelopathy. As recorded by patients using a diary card, 76% of the F2 compared with 81% of the F13 patients had dysphagia associated with their RT. This was transient, lasting for a median of 6.5 days in the F2 group compared with 14 days in the F13 group. In conclusion, the F2 regimen had a more rapid palliative effect. In the F13 group, although treatment-related dysphagia was worse, survival was longer.

Within gas turbines the ability to design shorter aggressive S-shaped ducts is advantageous from a performance and weight saving perspective. However, current design philosophies tend to treat the S-shaped duct as an isolated component, neglecting the potential advantages of integrating the design with the upstream or downstream components. In this paper, such a design concept is numerically developed in which the upstream compressor outlet guide vanes are incorporated into the first bend of the S-shaped duct. Positioning the vane row within the first bend imparts a strong radial gradient to the pressure field within the vane passage. Tangential lean and axial sweep are employed such that the vane geometry is modified to exactly match the resulting inclined static pressure field. The integrated design is experimentally assessed and compared to a conventional nonintegrated design on a fully annular low speed test facility incorporating a single stage axial compressor. Several traverse planes are used to gather five-hole probe data which allow the flow structure to be examined through the rotor, outlet guide vane and within the transition ducts. The two designs employ almost identical duct geometry, but integration of the vane row reduces the system length by 21%. Due to successful matching of the static pressure field, the upstream influence of the integrated vane row is minimal and the rotor performance is unchanged. Similarly, the flow development within both S-shaped ducts is similar such that the circumferentially averaged profiles at duct exit are almost identical, and the operation of a downstream component would be unaffected. Overall system loss remains nominally unchanged despite the inclusion of lean and sweep and a reduction in system length. Finally, the numerical design predictions show good agreement with the experimental data thereby successfully validating the design process.

Within gas turbines the ability to design shorter aggressive S-shaped ducts is advantageous from a performance and weight saving perspective. However, current design philosophies tend to treat the S-shaped duct as an isolated component, neglecting the potential advantages of integrating the design with the upstream or downstream components. In this paper such a design concept is numerically developed in which the upstream compressor outlet guide vanes are incorporated into the first bend of the S-shaped duct. Positioning the vane row within the first bend imparts a strong radial gradient to the pressure field within the vane passage. Tangential lean and axial sweep are employed such that the vane geometry is modified to exactly match the resulting inclined static pressure field. The integrated design is experimentally assessed and compared to a conventional non-integrated design on a fully annular low speed test facility incorporating a single stage axial compressor. Several traverse planes are used to gather five-hole probe data which allow the flow structure to be examined through the rotor, outlet guide vane and within the transition ducts. The two designs employ almost identical duct geometry, but integration of the vane row reduces the system length by 21%. Due to successful matching of the static pressure field, the upstream influence of the integrated vane row is minimal and the rotor performance is unchanged. Similarly the flow development within both S-shaped ducts is similar such that the circumferentially averaged profiles at duct exit are almost identical, and the operation of a downstream component would be unaffected. Overall system loss remains nominally unchanged despite the inclusion of lean and sweep and a reduction in system length. Finally, the numerical design predictions show good agreement with the experimental data thereby successfully validating the design process.Copyright © 2011 by Rolls-Royce plc

Subpicosecond time-resolved white-light continuum measurements of the nondegenerate two-photon absorption spectra of ZnSe, ZnS and ZnO, with pump photon energy 1.76 eV, are reported. The spectra presented cover a photon energy range of 1 eV. The results are found to agree well both in absolute value and frequency dependence with a model for the two-photon transition probability incorporating the Kane band structure and nonparabolicity.

Picosecond angularly-resolved excite-probe measurements have been used to make the first identification of a negative refractive optoelectronic nonlinearity in the ZnSe material deposited in thin-film nonlinear interference filters. A positive thermal refractive nonlinearity becomes dominant within 6 ps. We attribute the ultrafast relaxation of the photoexcited carriers to surface recombination at grain boundaries within the material.

This work reports the results of nonlinear absorption and nonlinear fluorescence studies carried out on a 0.8 M solution of the complex in THG in the spectral range 450 to 700 nm. Nonlinear absorption results demonstrate that this material exhibits optical limiting behavior over this entire spectral band when excited with nanosecond pulses. Results of nonlinear fluorescence and excite probe studies show that at wavelengths longer than 530 nm, the nonlinear absorption is a consequence of the pathway: two-photon absorption from the S/sub 0/ to the S/sub 1/ state, fast intersystem crossing in less than 300 ps from S/sub 2/ to T/sub 1/, followed by excited state absorption from T/sub 1/ to T*. Fluorescence studies as a function of the excite wavelength show that the two-photon absorption coefficient has little variation with wavelength in the region 550 to 700 nm. Detailed studies of the nonlinear absorption behavior at 595 nm reveal that the nonlinear absorption has a significant contribution from the triplet excited state absorption, resulting in an optical limiting performance that is not strongly dependent on pulse length.

We report novel measurements of the room temperature refractive optical nonlinearities in a molecular beam epitaxy‐grown ZnSe epilayer at frequencies near to the band edge. Time‐resolved changes in the transmission spectrum due to a two‐photon generated plasma of free carriers are monitored with a broad‐band white‐light continuum probe. The refractive index changes, measured for photon energies between 0.8 and 0.05 eV below the free‐exciton line at 2.68 eV, with photoexcited carrier densities of (2–5)×1018 cm−3, are found to be in good agreement with a many‐body plasma calculation.

Carrier recombination processes in thin‐film epitaxial ZnSe are investigated using a transient‐grating technique. For photoexcitation levels in the 1017–1018 cm−3 range the dominant recombination mechanism is found to be radiative, described by a rate coefficient of 8×10−9 cm3 s−1. For densities exceeding approximately 2×1018 cm−3 ultrafast grating recovery is observed, accompanied by line narrowing of the near‐band‐edge blue photoluminescence; this is interpreted as being due to stimulated radiative recombination.

Temporally and spectrally-resolved degenerate four-wave-mixing (FWM) techniques have been enormously successful in providing new information about fundamental nonlinear and coherent optical processes in atomic, molecular and solid state systems. Typically, in such studies, the time-integrated or time-resolved magnitude of the FWM emission (or its spectrum) is studied as a function of the input parameters (such as the fluence, time delays or the polarization states of the incident pulses), but the polarization state of the FWM signal itself has been largely ignored. Moreover, the few attempts that have been made to determine the polarization state of the FWM emission have been restricted to measuring the direction of polarization, but they have left the ellipticity and the degree to which the signal is unpolarized unspecified.

Ultrafast degenerate four-wave-mixing (FWM) techniques have been enormously successful in providing new information about coherent processes and excitonic effects in semiconductors. One of the techniques that has proven to be extremely powerful is to study the polarization dependence of the FWM process. Typically, these studies have addressed the dependence of the magnitude of the FWM signal (or its spectrum) on the incident polarizations, and there have been very few attempts to monitor the polarization state of the FWM signal itself. Moreover, the attempts that have been made have been restricted to measurements of the direction of polarization (ignoring the ellipticity and degree of polarization) and, therefore, they have not completely specified the polarization state of the emitted light. In addition, these measurements have been restricted to positive delays.

All four of the Stokes parameters of the time-integrated degenerate four-wave mixing signal from a GaAs/${\mathrm{Al}}_{\mathit{x}}$${\mathrm{Ga}}_{1\mathrm{\ensuremath{-}}\mathit{x}}$As multiple quantum well are measured as a function of the relative angle between the linear polarizations of the pump and the probe and of the incident fluence, thus completely characterizing the polarization state of the signal. The degree to which the signal is polarized, the ellipticity, and the orientation of the polarization ellipse are found to be strongly dependent on the orientation of the incident polarizations and on fluence. The principal features can be qualitatively understood in terms of a simple model that includes density-dependent dephasing and local-field corrections.

The behavioral symptoms associated with AD are a critical aspect of the disease. They provide an additional avenue not only for understanding AD but for implementing interventions. The nature of behavioral disorders in AD is complicated by a number of factors that interact and contribute to the development of problematic behavior. It is difficult to determine whether the behavior is the result of neurodegeneration, cognitive dysfunction, previous experiences, current stressors, independently coexisting psychopathology, or a combination of these factors. In any case, behavioral disturbances need to be more clearly defined and objectively measured. To understand and treat behavioral disturbances in AD, all biopsy-chosocial factors must be examined simultaneously. Currently, there is little that can be done to treat the cognitive components of AD. Consequently, our most successful and beneficial interventions may focus on the remediable behavioral manifestations of the disease. The most valuable treatment approach for patients with AD and their caregivers interweaves medications, psychosocial services, environmental strategies, and caregiver education.

A powerful technique for studying the excitation dynamics of thin-film condensed matter is demonstrated. The field-enhancement within a Fabry-Perot etalon, and the sensitivity of such a structure to the optical coefficients of the spacer layer material, is combined with the time and spectral resolution afforded by use of time-delayed picosecond-continuum monitoring. Applied to ZnSe interference-filter material the optoelectronic refractive nonlinearity is identified, however rapid lattice heating is observed leading to dominance of the optothermal nonlinearity (of opposite sign) within 3 ps after photoexcitation.

We report an experimental investigation to map out the spectral dependence of excited-state absorption in a Pt:ethynyl complex. The cross section for triplet state absorption (T1→T*),σT, was found to peak with a value of σT∼2.2×10-16 cm2 at 600 nm. The shape of this absorption peak was found to be the same for excitation at 355 and 532 nm, further supporting our interpretation of the electronic properties of the molecule. Broadband limiting against visible, nanosecond pulses was observed in an optical limiting test-bed.

Results are presented to indicate that the material bis((4-(phenylethynyl)phenyl)ethynyl)bis(tribu- tylphosphine) platinum (II) shows promise as a broadband optical limiter in the visible that will be effective over a large range of pulse lengths from picoseconds to hundreds of nanoseconds.

The complete polarization state of the degenerate four-wave mixing signal from a GaAs/AlxGa1-xAs multiple quantum well is determined by time resolution of all four of its Stokes parameters as a function of the relative angle between the two linear input polarizations. The degree of ellipticity and the orientation of the polarization ellipse are both observed to vary dramatically in time, and the temporal evolution is found to depend strongly on the orientation of the input polarizations. These time-resolved results are shown to be consistent with previous measurements of the time-integrated Stokes parameters and to provide new constraints for physical models. The results are shown to be qualitatively consistent with a phenomenological model requiring the inclusion of both many-body interactions and biexcitonic effects.

We report single-wavelength subpicosecond and nanosecond excite-probe and four-wave mixing experiments near the exciton resonance in p-toluene sulfonate polydiacetylene. Contributions to the third-order susceptibility χ(3) resulting from phase-space filling, photoinduced absorption, and two-photon absorption are identified. A three-level rate-equation model that accounts for the change in sign of the nonlinear absorption observed at near-resonant frequencies is discussed.

$\ensuremath{\gamma}$ radiation from targets of $^{7}\mathrm{Li}$, $^{9}\mathrm{Be}$, $^{12}\mathrm{C}$, $^{13}\mathrm{C}$, and $^{16}\mathrm{O}$ bombarded by ${\ensuremath{\pi}}^{\ensuremath{-}}$ and ${\ensuremath{\pi}}^{+}$ at energies between 60 and 300 MeV was uniquely associated with states formed by removing a single nucleon by the ($\ensuremath{\pi},\ensuremath{\pi}N$) reaction. All yields were found to reflect the well-known 3-3 resonance near 180 MeV in the pion-nucleon system. Ratios of yields for ${\ensuremath{\pi}}^{\ensuremath{-}}$ and ${\ensuremath{\pi}}^{+}$ beams were measured for $^{7}\mathrm{Li}$, $^{9}\mathrm{Be}$, and $^{13}\mathrm{C}$. These ratios were very similar to one another and to previous results on $^{12}\mathrm{C}$, $^{14}\mathrm{N}$, and $^{16}\mathrm{O}$ for neutron removal. Several reaction mechanisms based on quasifree processes are tested by comparison to the data, and all are rejected.

Differential cross sections for the (..pi../sup -/,n) reactions in /sup 3/He and /sup 4/He have been measured at energies of 100, 200, and 290 MeV. The angular distributions for /sup 3/He and /sup 4/He are different, with the /sup 4/He characterized by an oscillatory pattern with a dip at a fixed angle of approx. = 70/sup 0/. The forward-angle cross sections show a simple dependence upon momentum transfer for both /sup 3/He and /sup 4/He. These results are discussed in the context of single-nucleon and multinucleon reaction diagrams.

Differential cross sections for the reaction /sup 3/He(..pi../sup -/,..pi../sup 0/)/sup 3/H at energies of 200, 250, 275, and 290 MeV over the angular region 80 /sup 0/ < or approx. = theta/sub c.m./ < or approx. = 150/sup 0/ are presented. Comparison is made with theoretical predictions based on Glauber theory and optical-potential calculations. Neither approach gives a satisfactory description on the data; in particular, the observed energy dependence is much smaller than the theoretical predictions.

Outgoing-nucleon charge exchange has been used to explain reduction in ..pi..-N isospin selectivity in a large number of nucleon-removal experiments. The present work tests the validity of this model by measuring the total cross sections for nucleon removal to the 4.44-MeV, T = 0 and the 15.11-MeV, T = 1 states in /sup 12/C, where analog charge exchange is possible for the latter, but not the former state.

Neon K X-ray spectra resulting from O4+ and Cl4+ bombardment are observed to have dissimilar K alpha satellite intensities. These results are in contrast to similar measurements made using C6+, N6+ and O6+ bombardment.

Bombardment of cobalt with 42 MeV oxygen ions is seen to produce multiple inner shell electron excitation.Kα andKβ X-rays are measured and compared to Hartree-Fock-Slater calculated energies. This study of cobalt is the highestZ element where the satellite X-ray spectrum has been studied with good resolution.

De-excitation γ-rays have been detected from nuclear states following positive pion induced two-nucleon removal from 12 C and four-nucleon removal from 16 O. Excitation functions for population of discrete states were obtained for positive pions of 75, 125, 150, 200, 225, 250 and 290 MeV. The pion-nucleon (3, 3) resonance is not reflected in the cross sections for either reaction. Implications of the observed energy dependence are discussed.

Oxygen (plus six) and (plus eight) at 30 MeV incident energy have been used to induce Auger electron spectra of Ne. The high instrumental resolution (0.02% FWHM) spectra show specifically that the charge state of the incident oxygen ion considerably affects the distribution of the K-Auger electron yield among the charge states of multiply ionized neon.

Initial high resolution measurements of projectile electron emission spectra for beam gas collisions are reported. The Auger electron decay of beams of O + , O 2+ , and O 3+ at 3, 8, and 18 MeV, respectively, excited by single collisions with He, Ne, and Ar was measured at a lab emission angle of 23.7° with a 36 cm double focussing electrostatic analyzer. Although prompt transitions are found to predominate the spectra, several weak lines are attributed to transitions from metastable states. Spectral features are seen to vary greatly as a function of exciter gas and as a function of projectile charge state and energy.

Total cross sections for the knockout reactions $^{7}\mathrm{Li}({\ensuremath{\pi}}^{\ensuremath{-}},{\ensuremath{\pi}}^{\ensuremath{-}}n)^{6}\mathrm{Li}$ and $^{7}\mathrm{Li}({\ensuremath{\pi}}^{+},{\ensuremath{\pi}}^{+}n)^{6}\mathrm{Li}$ to 3.56-MeV ${0}^{+}$ $T=1$ state have been measured at ten energies between 50 and 290 MeV by detecting the direct $\ensuremath{\gamma}$ de-excitation. As found in previous work, the ratio $\frac{\ensuremath{\sigma}({\ensuremath{\pi}}^{\ensuremath{-}},{\ensuremath{\pi}}^{\ensuremath{-}}n)}{\ensuremath{\sigma}({\ensuremath{\pi}}^{+},{\ensuremath{\pi}}^{+}n)}$ on the (3,3) resonance is significantly less than the value of 3 expected from free pion-nucleon results.

The K X-ray spectrum from a 30 MeV chlorine ion beam was measured as it was stopped in aluminium. The spectrum exhibits six lines located approximately half way between the Kalpha 1,2 and Kbeta 1,3 lines of chlorine. These lines can be interpreted as Kalpha transitions with various 2p shell vacancies and with the M shell electrons partially stripped.

Targets of Al and Al2O3 were bombarded by 0.8 MeV protons and 3.2 MeV alpha particles and the subsequent X-ray yield measured. The Kα X-ray spectra of Al and Al2O3 show fairly good agreement in both the proton and alpha-induced spectra; however, the structure in the Kβ X-ray spectra deviate from one another in both cases. These results are interpreted as effects due to the chemical bonding of the oxygen atoms to aluminum.

Elastomer modification is an effective way of toughening glassy epoxy resins. The toughening mechanisms of phase separation and gellation have been studied extensively. This paper reports the effects of carboxyl terminated acrylonitrile rubber on several single component epoxy adhesives, based on Epon 828 and cured with dicyandiamide. Variables include accelerator type and level, cure temperature and elastomer level. There is an optimum amount of rubber which may be added to each system to yield maximum shear strength. Peel strength is maximized in two regions. Rapid gellation of these adhesives may be detrimental to the phase separation and chain extension mechanism and thereby cause lowering of fracture toughness and strength properties.

A study is reported which explores the feasibility of a highway transportation system that electromagnetically transfers energy to vehicles from powered roadways for high-speed or long-range travel, and uses energy stored in the vehicles for other travel. The energy coupling between roadway and vehicle is functionally similar to a transformer. The roadway energy source is imbedded flush with the roadway surface. When vehicle's energy pickups are suspended over the source, energy is magnetically coupled through the clearance gap between source and pickup. Analyses and modeling indicated that adequate power can be efficiently coupled by the system. The economics of the system appear to be favorable, and no implementational problems were identified that would make the system impractical. In addition to the engineering development of the power system, including performance verification with prototype hardware, continuing efforts should further address the effects of stray magnetic fields, the compatibility of the system with existing automobiles, electrical safety, and the process of transition from the use of existing automobiles.

Radiocarpal dislocation is a rare injury. The authors reviewed seven cases with this injury and identified two groups of patients. Type I involves a dislocation of only the radiocarpal joint, while Type II involves intercarpal dislocation also. Four patients were included in Type I dislocation (3 dorsal and 1 volar). The other three patients had Type II dislocations, all of which were volar dislocations. Two patients had evidence of injury to the median and ulnar nerves at the time of the injury and both recovered completely. Closed reduction was possible with good results in three patients with Type I dislocation. All patients with Type II dislocation required open reduction and all had residual problems. The distinction between Type I and Type II is essential in order to evaluate the full extent of the injury. Closed reduction should always be attempted in Type I dislocation. Type II dislocation should be treated by open reduction and repair of all torn ligaments.