bluuebunny/crossref_metadata_2025 huggingface dataset:
The African easterly jet in the ECMWF Integrated Forecast System: 4D‐Var analysis
Authors: Tompkins A. M. , Diongue‐Niang A. , Parker D. J. , Thorncroft C. D.
Published: November 2005

In August 2000, the Met Office C‐130 research flight aircraft conducted four sorties over the western Sahel region, making dropsonde measurements at an unprecedented resolution. These were used as an independent validation source to assess the quality of the analysis of the African easterly jet (AEJ) in the ECMWF Integrated Forecast System (IFS). The model was found to produce a reasonably accurate representation of the AEJ location and structure. Peak zonal winds were within 5 m s−1 of the observed values for the two flights that performed transects across the jet. Temperature errors were less than 1 K above the boundary layer, and the gross features of the humidity distribution were reproduced. The analysis was also able to capture the weak African easterly wave activity present during the campaign, but was not capable of reproducing the observed daily variability in boundary‐layer height, with a too deep mixed layer on two days resulting in a significant dipole error structure in temperature and relative humidity.

Analysis experiments were conducted in which various observations were excluded from the system to determine which were important for the diagnosis of the jet. Satellite data had a minor influence on the jet structure. Conventional platforms such as radiosondes and pilot balloons were more important. The thermodynamical information from radiosondes had a greater impact on the jet winds than the direct assimilation of the wind observations, made possible by the 4D variational assimilation system where thermodynamic information can impact on the dynamics. In contrast, the jet structure improved when surface observations (SYNOPs) were removed from the system, possibly due to the disparity between the radiosonde and SYNOP station humidity information over these regions. The investigation implied that all observational information is incorporated into the analysis in a well‐balanced manner, rather than being dominated by a single source. The system was able to assimilate the dropsonde data, which led to an improved dynamical and thermodynamical structure of the jet. Copyright © 2005 Royal Meteorological Society
On the scattering phase‐function of non‐symmetric ice‐crystals
Authors: Baran Anthony. J. , Shcherbakov V. N. , Baker B. A. , Gayet J. F. , Lawson R. P.
Published: November 2005

Theoretical phase‐functions representing randomly oriented fractal ice‐crystals, bullet‐rosettes, ice aggregates, and an ensemble of ice crystals are compared to measured phase‐functions using a Polar Nephelometer located in the Antarctic. The Polar Nephelometer operated at a wavelength of 0.80 µm and measured the scattering phase‐functions of individual ice‐crystals between the scattering angles of 5.86° and 167°. The Polar Nephelometer was operated in tandem with a Cloud Particle Imager (supplied by SPEC Inc.) both were situated at the South Pole Amundsen–Scott base station during January 2002. In this paper we report on a sample of Polar Nephelometer data obtained over a time interval of 2000 seconds consisting of 3256 phase‐functions measured from individual ice‐crystals. The 3256 measured phase‐functions were averaged to produce an ensemble‐averaged phase‐function. The theoretical phase‐functions have been compared to the measured ensemble‐averaged phase‐function. The paper demonstrates that phase functions representing single ice‐crystal geometries do not reproduce the measured data well. However, the theoretical phase‐function representing scattering from an ensemble of ice crystals is found to be the best description of the measured phase‐function over all scattering angles. Copyright © 2005 Royal Meteorological Society.
A 3D stochastic cloud model for investigating the radiative properties of inhomogeneous cirrus clouds
Authors: Hogan Robin J. , Kew Sarah F.
Published: November 2005

The three‐dimensional structure of clouds is known to be important for determining their radiative effects, but it is difficult to obtain this structure directly from observations. In this paper a stochastic model is described that is capable of simulating the structural properties unique to cirrus: fallstreak geometry and shear‐induced mixing. We first present an analysis of time–height cloud radar sections from southern England to extract the cirrus parameters of interest. It is found that horizontal power spectra of the logarithm of ice‐water content (estimated from radar reflectivity factor and temperature) typically exhibit a spectral slope of around −5/3 near cloud top that decreases with depth into the cloud, to values as low as −3.5 in some cases. This decrease can be explained by wind shear coupled with a spread of particle fall speeds leading to a homogenization that acts preferentially at smaller scales. The power spectra exhibit a distinct scale break, becoming flat at scales larger than around 50 km (the ‘outer scale’). The orientation of the fallstreaks may be predicted from the profile of mean wind and mean ice fall speed. We then describe the stochastic model, which takes as input profiles of the mean and fractional standard deviation of ice‐water content, spectral slope, outer scale and wind speed. It first generates an isotropic 3‐D fractal field by performing an inverse 3‐D Fourier transform on a matrix of simulated Fourier coefficients with amplitudes consistent with the observed 1‐D spectra. Random phases for the coefficients allow multiple realizations of a cloud with the same statistical properties to be generated. Then horizontal slices from the domain are manipulated in turn to simulate horizontal displacement and changes to the spectra with height. Finally the field is scaled to produce the observed mean and fractional standard deviation of ice‐water content. Vertical 2‐D slices extracted from the domain are very similar in appearance to cloud radar observations. Radiative‐transfer calculations using the independent column approximation are used to show that the different fallstreak orientation resulting from different wind shears can change mean top‐of‐atmosphere radiative fluxes by in excess of 45 W m−2 in the short‐wave and 15 W m−2 in the long‐wave. The effect of wind shear to induce horizontal mixing causes an additional but smaller radiative effect. We also investigate the biases that would be expected from the assumptions made in the radiation schemes of general‐circulation models (GCMs). It is found that there is some compensation between the errors arising from the assumptions of horizontal homogeneity and maximum‐random overlap; if a GCM were to improve the overlap assumption but still assume clouds to be horizontally homogeneous then the total error in cloud radiative effect would be likely to increase. Copyright © 2005 Royal Meteorological Society.
Use of randomization to diagnose the impact of observations on analyses and forecasts
Authors: Desroziers G'erald , Brousseau Pierre , Chapnik Bernard
Published: November 2005

A method is proposed to diagnose the impact of a complete set, or subsets, of observations on the reduction of error variance in an analysis and in the subsequent forecasts run from this analysis. A practical method to estimate the error reduction, based on a randomization procedure, is also introduced and investigated in a simple framework given by the analysis and forecast of wind on a circular domain using the nonlinear Burger's equation. The randomization procedure is also applied and tested in the French ARPEGE 4D‐Var assimilation. The first results in a real‐size data assimilation system are realistic and provide useful information on the use of observations in an operational analysis. Copyright © 2005 Royal Meteorological Society
Water‐vapour variability within a convective boundary‐layer assessed by large‐eddy simulations and IHOP_2002 observations
Authors: Couvreux F. , Guichard F. , Redelsperger J.‐L. , Kiemle C. , Masson V. , Lafore J.‐P. , Flamant C.
Published: November 2005

This study presents a comprehensive analysis of the variability of water vapour in a growing convective boundary‐layer (CBL) over land, highlighting the complex links between advection, convective activity and moisture heterogeneity in the boundary layer. A Large‐eddy Simulation (LES) is designed, based on observations, and validated, using an independent data‐set collected during the International H2O Project (IHOP_2002) field‐experiment. Ample information about the moisture distribution in space and time, as well as other important CBL parameters are acquired by mesonet stations, balloon soundings, instruments on‐board two aircraft and the DLR airborne water‐vapour differential‐absorption lidar. Because it can deliver two‐dimensional cross‐sections at high spatial resolution (140 m horizontal, 200 m vertical), the airborne lidar offers valuable insights of small‐scale moisture‐variability throughout the CBL. The LES is able to reproduce the development of the CBL in the morning and early afternoon, as assessed by comparisons of simulated mean profiles of key meteorological variables with sounding data. Simulated profiles of the variance of water‐vapour mixing‐ratio were found to be in good agreement with the lidar‐derived counterparts. Finally, probability‐density functions of potential temperature, vertical velocity and water‐vapour mixing‐ratio calculated from the LES show great consistency with those derived from aircraft in situ measurements in the middle of the CBL. Downdraughts entrained from above the CBL are governing the scale of moisture variability. Characteristic length‐scales are found to be larger for water‐vapour mixing‐ratio than for temperature

The observed water‐vapour variability exhibits contributions from different scales. The influence of the mesoscale (larger than LES domain size, i.e. 10 km) on the smaller‐scale variability is assessed using LES and observations. The small‐scale variability of water vapour is found to be important and to be driven by the dynamics of the CBL. Both lidar observations and LES evidence that dry downdraughts entrained from above the CBL are governing the scale of moisture variability. Characteristic length‐scales are found to be larger for water‐vapour mixing‐ratio than for temperature and vertical velocity. In particular, intrusions of drier free‐troposphere air from above the growing CBL impose a marked negative skewness on the water‐vapour distribution within it, both as observed and in the simulation. Copyright © 2005 Royal Meteorological Society.
Assimilation of ozone data from the Michelson Interferometer for Passive Atmospheric Sounding
Authors: Wargan Krzysztof , Stajner Ivanka , Pawson Steven , Rood Richard B. , Tan Wei‐wu
Published: November 2005

Global ozone profiles from the Michelson Interferometer for Passive Atmospheric Sounding (MIPAS) were added to an assimilation system that includes ozone data from the Solar Backscatter Ultraviolet/2 (SBUV/2) instrument. Substantial impacts were found and investigated. MIPAS ozone profiles have a vertical resolution close to 3 km, retrieved from infrared limb emission radiances, with a height‐dependent error of 4–8%; they were used over 12 layers, spanning between 60–80 hPa and 0.15–0.25 hPa. As a research instrument, MIPAS provides variable coverage from day to day, with occasional data gaps of several days. The operational SBUV/2 data give regular temporal coverage in sunlit areas, yielding total columns and partial profiles, assimilated for Umkehr layers 3 (126–63 hPa) to 12 (<0.25 hPa), with errors comparable to MIPAS near the ozone maximum but increasing substantially at higher and lower levels. The higher accuracy of MIPAS data leads to substantial improvements in the assimilated ozone below the ozone maximum when compared to accurate in situ (ozonesonde) and space‐based (occultation) data; vertical gradients in the lower stratosphere are improved. In the Arctic winter of 2002/03, the ability of MIPAS to sample the vortex interior leads to substantial beneficial impacts. In the tropics, assimilation of MIPAS profiles improves analyses in the lower stratosphere and provides substantially better agreement with occultation data in the middle stratosphere, near the ozone maximum. This offsets an underestimate in the SBUV‐only analyses caused by transport errors in the forecast. The global improvements in the assimilation lead to local improvements when compared against individual measured ozone profiles, where vertical structures are determined by height dependence in horizontal advection from diverse regions. The spatio‐temporal variability in the assimilation is more realistic when MIPAS data are included. Experiments to examine the impacts of temporal gaps in the MIPAS data reveal a ‘memory’ of 5–10 days in the transport‐dominated lower stratosphere. In the middle stratosphere, the impact of missing MIPAS data is more complex; transport errors cause a large initial impact followed by ozone values typical of SBUV assimilation. Copyright © 2005 Royal Meteorological Society.
The diurnal cycle of the West African monsoon circulation
Authors: Parker D. J. , Burton R. R. , Diongue‐Niang A. , Ellis R. J. , Felton M. , Taylor C. M. , Thorncroft C. D. , Bessemoulin P. , Tompkins A. M.
Published: November 2005

Using numerical model analyses, it is shown that there is a coherent diurnal cycle of the West African monsoon winds. As has been observed in previous studies of arid and semi‐arid areas, the winds are at their weakest in the afternoon when the convective boundary layer (CBL) is deep, and intensify overnight when the boundary‐layer turbulence is much weaker. This diurnal cycle is maximized in the northern part of the monsoon layer, where the meridional pressure gradient and the diurnal cycle of the CBL are both strong.

The diurnal cycle can also be resolved in surface and upper‐air data, which show how the nocturnal meridional circulation acts to stratify the lower part of the monsoon layer. In contrast, mixing in the daytime CBL acts to maintain the baroclinicity, as has been observed in laboratory flows. This pattern has implications for the efficiency of the monsoon circulation in the continental water budget, as well as in mixing of trace gases and aerosols between the surface layer and the free troposphere. Vertical mixing occurs by day, while meridional advection, with isentropic upgliding and downgliding, is most efficient at night.

Finally, high‐resolution observations from the JET2000 experiment are used to show that there is mesoscale structure in the diurnally varying monsoon circulation. In the nocturnal flows, local circulations have been observed and appear to represent a response to recent deep convective events. In contrast, the daytime CBL properties at these scales have been shown in a previous study to map closely onto patterns of soil moisture, with horizontal advection playing a weaker role. Copyright © 2005 Royal Meteorological Society
Dynamics and microphysics of orographic precipitation during MAP IOP3
Authors: Pujol Olivier , Georgis Jean‐Francois , Chong Michel , Roux Frank
Published: November 2005

A dynamical and microphysical four‐dimensional study of an intense orographic precipitating system is carried out in the frame of MAP IOP3 (25–26 September 1999). High precipitation opportunely occurred in the range of the Swiss operational Doppler radar at Monte Lema (Switzerland), the US SPOL polarimetric Doppler radar and the French Ronsard Doppler radar both located near Lago Maggiore (Italy). Radar data have been combined to deduce four‐dimensional precipitation and wind fields during the most intense precipitation period (1600–2000 UTC on 25 September). The organization and evolution of the microphysical field have been obtained through an analysis of SPOL polarimetric data: nine hydrometeor classes (light, moderate and heavy rain, hail, rain–hail and graupel–hail mixtures, dry and wet snow, and ice crystals) are inferred by means of a fuzzy‐logic method initially developed by Vivekanandan et al.

The temporal mean study of reflectivity fields reveals that the precipitation presents a convective pattern and is primarily located on the foothills and over the first mountain. Mean microphysical fields reveal rain below the 0 °C level, wet snow, ice crystals and dry snow above with an embedded 2 km deep layer of graupel–hail mixture. This suggests convective microphysical processes.

Temporal series of precipitation and wind fields are then analysed in order to characterize in detail the organization and evolution of the system. Three stages were identified: first an elongated structure growing and intensifying over the lake while moving towards the Alps, then a spreading of the system over the mountains and finally a weakening over Lago Maggiore and the mountains. It has to be noted that the lake and the first mountainous peaks were important factors in the generation and the intensification of convective cells: the lake acts as a secondary moisture source which can favour local convection, and mountainous slopes favour updraughts which permit a downwind extension of the system by ejection of precipitating particles according to the fountain particles concept. Finally, through a temporal and spatial microphysical study, coalescence below the 0 °C level, riming and freezing above, are concluded to be the major processes in the formation of intense precipitation. The essential role of ice phase in the formation and enhancement of precipitation has been highlighted. Copyright © 2005 Royal Meteorological Society
A monotonic and positive–definite filter for a Semi‐Lagrangian Inherently Conserving and Efficient (SLICE) scheme
Authors: Zerroukat Mohamed , Wood Nigel , Staniforth Andrew
Published: November 2005

A new monotonic and positive–definite filter is incorporated into an existing Semi‐Lagrangian Inherently Conserving and Efficient (SLICE) scheme for transport problems in both Cartesian and spherical geometry. The SLICE scheme is based on a control‐volume approach that uses multiple sweeps of a one‐dimensional O (Δx4) conservation remapping algorithm along predetermined cascade directions. The new filter combines a selective detection algorithm, to pinpoint regions of non‐monotonic behaviour, with a hierarchical reduction of the degree of the piecewise reconstruction in such regions, to re‐establish monotonicity. The enhanced, monotonic and positive–definite, SLICE scheme is tested in one dimension, and then applied to standard two‐dimensional test problems in both Cartesian and spherical geometries. Comparisons with published results of other conservative semi‐Lagrangian schemes show that it performs well. © Crown copyright, 2005.
Probabilistic physically based cloud screening of satellite infrared imagery for operational sea surface temperature retrieval
Authors: Merchant C. J. , Harris A. R. , Maturi E. , Maccallum S.
Published: November 2005

We propose and demonstrate a fully probabilistic (Bayesian) approach to the detection of cloudy pixels in thermal infrared (TIR) imagery observed from satellite over oceans. Using this approach, we show how to exploit the prior information and the fast forward modelling capability that are typically available in the operational context to obtain improved cloud detection. The probability of clear sky for each pixel is estimated by applying Bayes' theorem, and we describe how to apply Bayes' theorem to this problem in general terms. Joint probability density functions (PDFs) of the observations in the TIR channels are needed; the PDFs for clear conditions are calculable from forward modelling and those for cloudy conditions have been obtained empirically. Using analysis fields from numerical weather prediction as prior information, we apply the approach to imagery representative of imagers on polar‐orbiting platforms. In comparison with the established cloud‐screening scheme, the new technique decreases both the rate of failure to detect cloud contamination and the false‐alarm rate by one quarter. The rate of occurrence of cloud‐screening‐related errors of >1 K in area‐averaged SSTs is reduced by 83%. Copyright © 2005 Royal Meteorological Society.
Late laryngeal radionecrosis in severe arteriosclerosis
Authors: Shimizu Naoki , Okamoto Hideyuki , Fukuda Takehiko , Yane Katsunari , Hosoi Hiroshi
Published: November 2005

Laryngeal necrosis is a serious complication that usually occurs within the first year following completion of radiotherapy, although it is reported that cases can develop after a long period of latency. Factors such as dosage and irradiation technique employed, tumour invasion into the laryngeal cartilage, infection, continued smoking, trauma and general vascular condition of the patient have been considered to increase the rate and degree of development of radionecrosis. We report an unusual case of laryngeal radionecrosis in a patient with hypertension, hyperlipidaemia, diabetes and a history of cigarette smoking, which developed 25 years after radiotherapy for laryngeal carcinoma. His systemic illnesses and continued smoking were speculated to have contributed to the progress of the radionecrosis, suggesting that cessation of smoking and control of arteriosclerotic diseases should be considered to decrease its incidence.
Survival of a patient with endopharyngeal common carotid blow out due to parapharyngeal abscess as an unusual complication of cholesteatoma
Authors: Singh M , Bandyopadhyay S , Mohindra N , Mishra L S
Published: November 2005

Parapharyngeal abscess as a complication of cholesteatoma is an uncommon entity. Endopharyngeal common carotid artery rupture due to parapharyngeal abscess is also uncommon, and these cases usually end fatally. We present a 17-year-old male with parapharyngeal abscess due to cholesteatoma who developed an endopharyngeal common carotid blow out and survived after common carotid ligation without any neurological sequalae.
Epilepsy following middle-fossa extradural retraction: implications for driving
Authors: Aggarwal R , Green K M J , Ramsden R T
Published: November 2005

New-onset epilepsy has several social and financial repercussions. Development of seizures after middle-fossa surgery is uncommon. We present two subjects who developed epilepsy following middle-fossa surgery, requiring treatment with anticonvulsants, and discuss the implications.
The aetiology and management of atrophic rhinitis
Authors: Dutt Sunil Narayan , Kameswaran Mohan
Published: November 2005

Atrophic rhinitis is a chronic, debilitating and recalcitrant disease of the nasal cavities that is prevalent in several parts of the world. It has unique epidemiological features and clinical characteristics. Clinicians and researchers for decades have tried to postulate theories for the aetiology of the primary form of the disease. Management of the disease has seen several medical therapeutic regimens including alternative forms of medicine. Surgical options for the condition are also not completely satisfactory with a number of failures and recurrences. The authors provide here a comprehensive review of the existing literature as regards the aetiology and management of this refractory condition.
Pharyngeal perforation: a late complication of cervical spine surgery
Authors: Woolley S L , Smith D R K
Published: November 2005

Anterior cervical spine fusion and stabilization is a well-recognized procedure for a number of cervical spine disorders. Unfortunately, the complex anatomy of the cervical spine means that these procedures are not without complications. Pharyngo-oesophageal perforation is a rare but potentially life-threatening complication of cervical spine surgery and may present intra-operatively, in the immediate post-operative period or many years later. We present the case of a gentleman with ankylosing spondylitis who presented with a pharyngeal perforation and fistula five years after cervical spine surgery.
Telomerase catalytic subunit gene expression does not influence survival of patients with squamous cell carcinoma of the larynx and hypopharynx: a case-control study
Authors: Luzar Boštjan , Poljak Mario , Fischinger Janez , Klopčič Ulrika , Gale Nina
Published: November 2005

Aims: to determine correlations between relative quantities of telomerase catalytic subunit m-ribonucleic acid (hTERT mRNA) and conventional clinicopathological parameters (such as site, size and grade of tumour, the presence of regional lymph node metastases, and, in particular, survival) in patients with laryngeal and hypopharyngeal squamous cell carcinomas (SCCs).

Material and methods: The relative quantity of hTERT mRNA was analysed by a commercially available LightCycler Telo TAGGG hTERT Quantification Kit in 56 cases of SCC (40 laryngeal and 16 hypopharyngeal). The association with cancer-specific survival was evaluated by univariate and multivariate analysis.

Results: Location of the tumour in the hypopharynx was the only significant negative predictive factor for survival, as determined by univariate analysis (p = 0.028). Although a tendency towards a better overall survival was observed for female patients younger than 50 years, for lower tumour grades and sizes, and for the absence of regional lymph node metastases, the prognostic significance of these factors could not be confirmed. No differences existed in hTERT mRNA expression between laryngeal and hypopharyngeal SCCs. Furthermore, no correlation was found between the relative quantities of hTERT mRNA and the tumour size, regional lymph node metastases or survival of patients with laryngeal or hypopharyngeal SCCs.

Conclusions: The results of the present study suggest that genetic abnormalities other than telomerase reactivation are responsible for progression of laryngeal and hypopharyngeal SCCs.
Allergic fungal sinusitis (AFS) – earlier diagnosis and management
Authors: Singh Neeraj , Bhalodiya N H
Published: November 2005

Aim: To evaluate the criteria for diagnosing allergic fungal sinusitis and to maintain permanent drainage and ventilation, while preserving the integrity of mucosa. Methods: This is a prospective study of 251 patients with chronic rhinosinusitis with or without polyposis, of whom 199 were treated surgically. Mucus sample collection, nasal secretion culture, surgical specimen handling and histological evaluation of surgical specimens are described. The management included wide local endoscopic sinus debridement, adequate sinus aeration, post-operative use of steroids and antifungal therapy. Results: Fungal cultures of nasal secretions were positive in 201 (80.01 per cent) of 251 patients. Of the 199 surgical cases, fungal elements were found in 156 histological specimens (62.1 per cent). Allergic mucin was found in 182 patients (91.45 per cent). Nasal obstruction and proptosis were the commonest presentations. All pre-operative versus post-operative changes in AFS-associated complaints reached statistical significance of p < 0.001. The ethmoid sinus was commonly involved with adjacent lamina papyracea exhibiting demineralization in 26.6 per cent of cases. Intracranial extension was seen in 15 cases. Recurrence was noted in 11 cases. Conclusion: Comprehensive treatment with endoscopic sinus surgery, steroids and antifungal therapy is needed. AFS is readily recurrent. Long-term follow up is important.
Endonasal endoscopic repair of anterior skull-base fistulas: the Kuala Lumpur experience
Authors: Gendeh B S , Mazita A , Selladurai B M , Jegan T , Jeevanan J , Misiran K
Published: November 2005

The purpose of this retrospective study is to determine the pattern of cerebrospinal fluid (CSF) rhinorrhoea presenting to our tertiary referral centre in Kuala Lumpur and to assess the clinical outcomes of endonasal endoscopic surgery for repair of anterior skull base fistulas. Sixteen patients were treated between 1998 and 2004. The aetiology of the condition was spontaneous in seven and acquired in nine patients. In the acquired category, three patients had accidental trauma and this was iatrogenic in six patients (five post pituitary surgery), with one post endoscopic sinus surgery (ESS). Imaging included computed tomography (CT) scan and magnetic resonance imaging (MRI). Endoscopic repair is less suited for defects in the frontal sinuses with prominent lateral extension and defects greater than 1.5 cm in diameter involving the skull base. Fascia lata, middle turbinate mucosa, nasal perichondrium and ear fat (’bath plug’) were the preferred repair materials in the anterior skull base, whereas fascia lata, cartilage and abdominal fat obliteration was preferentially used in the sphenoid leak repair. Intrathecal sodium flourescein helped to confirm the site of CSF fistula in 81.3 per cent of the patients. Ninety per cent of the patients who underwent ’bath plug’ repair were successful. The overall success rate for a primary endoscopic procedure was 87.5 per cent, although in two cases a second endoscopic procedure was required for closure. In the majority of cases endoscopic repair was successful, and this avoids many of the complications associated with craniotomy, particularly in a young population. Therefore it is our preferred option, but an alternative procedure should be utilized should this prove necessary.
Usefulness of technetium-99m methoxyisobutylisonitrile single-photon emission computed tomography and computed tomography in the evaluation of cervical lymph node metastasis
Authors: Lee Byung-Joo , Wang Soo-Geun , Goh Eui-Kyung , Kim Jun-Young , Kim In-Ju , Kim Hak-Jin
Published: November 2005

The aim of this study was to compare the effectiveness of technetium-99m methoxyisobutylisonitrile (99mTc-MIBI) single-photon emission computed tomography (SPECT) and computed tomography (CT) in evaluating cervical lymph node metastasis of head and neck cancer. Histopathologic results of 166 cervical lymph node levels in 31 neck-dissected patients were compared with pre-operative CT and 99mTc-MIBI SPECT findings about cervical lymph node metastasis, retrospectively. Sensitivity, specificity and predictability of CT and 99mTc-MIBI SPECT were 68.2, 93.1 and 89.8 per cent and 59.1, 87.5 and 83.7 per cent, respectively. When analysing CT and99mTc-MIBI SPECT together, sensitivity and specificity were 86.4 and 99.3 per cent, respectively. The combined use of 99mTc-MIBI SPECT and CT could increase the accuracy of cervical lymph node metastases detection, compared with separate use of either 99mTc-MIBI SPECT or CT.
Ectopic submandibular gland presenting as a swelling in the floor of mouth
Authors: Barlow S T , Drage N A , Thomas D W
Published: November 2005

The authors describe a patient who presented with a left sublingual swelling. Ultrasonic and sialographic investigation showed no salivary tissue in the expected left submandibular region, but a large salivary gland in the left floor of the mouth deep to the mylohyoid muscle. This is likely to represent an ectopically positioned submandibular gland.
A multipurpose landmark for skull-base surgery: Henle’s spine
Authors: Ulug Tuncay , Ozturk Adnan , Sahinoglu Kayihan
Published: November 2005

Objective: To determine whether Henle’s spine could be used as a reliable and multipurpose landmark for the other important structures of the skull base.

Materials and methods: Ninety-two specimens from 46 cadaveric adult dry skulls were studied. Two imaginary lines and a triangle were defined: a spinopterygoidal line extending from Henle’s spine to the root of the medial pterygoid plate, a bispinal line extending from one Henle’s spine to the contralateral one, and a parapetrosal triangle lying between the spinopterygoidal line, the bispinal line and the sagittal midline. The parapetrosal triangle encompasses nearly all the main structures of the skull base, including the petrosal internal carotid artery.

Results: Along the spinopterygoidal line the distance from Henle’s spine to the spine of the sphenoid was found to be about 3 cm, to the foramen spinosum 3.5 cm, to the posterior and anterior margins of the foramen ovale 4 and 4.5 cm, to the root of the lateral pterygoid plate 5 cm, to the root of the medial pterygoid plate 5.5 cm, and to the vomer 6.5–7 cm. Along the bispinal line, the distance from Henle’s spine to the stylomastoid foramen was found to be about 1.5 cm, to the lateral and medial margins of the jugular foramen 2.5 and 3.5 cm, to the external orifice of the hypoglossal canal 4 cm, and to the foramen magnum 5 cm.

Conclusion: Henle’s spine with its superficial and central position can be used to localize important anatomical structures during skull-base surgery.
Spitting in the ear: a falsified disease using video evidence
Authors: Bennett A M D , Bennett S M V , Prinsley P R , Wickstead M
Published: November 2005

We present the case of Munchausen’s syndrome by proxy (MSBP) in which the mother spat and placed blood in her child’s ear, and videoed the result, in order to gain the attentions of the medical profession. This is the first case report of this kind and may represent a disturbing trend in the use of digital photography and video to support factitious illnesses.
Upper neck spinal accessory nerve identification during neck dissection
Authors: Tatla T , Kanagalingam J , Majithia A , Clarke P M
Published: November 2005

Iatrogenic injury to the spinal accessory nerve (SAN) during neck dissection may result in significant and avoidable morbidity in the form of ’shoulder syndrome’. The authors describe a simple method, based on the anatomy of the sternocleidomastoid muscle (SCM), which allows consistent and rapid identification of the SAN in the upper neck during dissection, thereby facilitating its preservation.
Videoendoscopic surgery for inaccessible glottic lesions
Authors: Schindler Antonio , Capaccio Pasquale , Ottaviani Francesco
Published: November 2005

Objectives: Lesions in the anterior segment of the vocal fold are sometimes difficult to access by means of conventional suspension microlaryngoscopy under general anaesthesia because of anatomical factors such as short, stout and inflexible necks, reduced jaw protrusion, and long incisors. Various techniques have recently been proposed for the management of inaccessible glottic lesions, most of which are performed under general anaesthesia. The use of flexible videoendoscopic surgery under topical anaesthesia in two cases of anterior glottic lesions that could not be treated by means of conventional suspension laryngoscopy is described.

Study design: Case report.

Methods: A flexible videobronchoscope with an instrument channel was inserted transnasally on an out-patient basis. While the examiner carried out the endoscopy, an assistant manoeuvred the biopsy forceps through the instrument channel, and removed the lesion.

Results: Both patients underwent successful removal of an anterior glottic polyp, and the one-year follow-up evaluation revealed normal anatomy of the vocal folds and normal vocal function.

Conclusions: Flexible videoendoscopic surgery under topical anaesthesia is a safe, simple and minimally invasive procedure that can be considered as an alternative to traditional endoscopic surgery for inaccessible anterior glottic lesions.
Mediastinal tracheostomy: unilateral resection of the anterior chest wall
Authors: Lequeux T , Chantrain G , Thill M P , Saussez S
Published: November 2005

Since the first reliable mediastinal tracheostomy described by Grillo et al. in 1966, many new techniques have been described in order to reduce the number of complications. We here report the case of a 55-year-old man who was referred for surgery with post-radiochemotherapy recurrence of a double neoplasm of the pharyngolarynx extending to the proximal trachea and the medial part of the oesophagus. Through a median sternotomy, a pharyngolaryngoesophagectomy was performed with an extended tracheal resection. The reconstruction of the upper digestive tract was performed with a gastric pull-up. The mediastinal tracheostomy was performed with a pectoralis major muscular flap through a right unilateral resection of the manubrium, the right clavicular head and the right first and second costal cartilages. Historically, the mediastinal tracheostomy was performed through a large bilateral resection of the anterior chest wall, in order to prevent the tension on the tracheocutaneous sutures. Nowadays, with the possibility of various pedicled flaps, bilateral resection no longer seems to be necessary. This unilateral resection leads to a reduction in post-operative sequelae.
The influence of weather on the frequency of secondary post-tonsillectomy haemorrhage
Authors: Lee M S W , Montague M-L , Hussain S S M
Published: November 2005

The aim of this study was to determine whether certain weather variables influence the secondary post-tonsillectomy haemorrhage rate and to examine the influence of a change in these variables on secondary haemorrhage. This was a prospective study carried out in a tertiary referral institution. All patients undergoing bilateral tonsillectomy over a one-year period were included. Local weather data, including daily temperature (max/min), relative humidity and water vapour pressure, were acquired. All patients readmitted to our department with secondary post-tonsillectomy haemorrhage were recorded. Of 346 patients undergoing tonsillectomy, 32 developed secondary haemorrhage (9.2 per cent). A significant negative correlation was found between secondary haemorrhage rate and the average monthly temperature (max/min) and water vapour pressure (Pearson’s correlation = −0.8) (p ≤ 0.002). These results suggest that performing tonsillectomy in warmer weather when the water vapour pressure is higher may reduce the secondary haemorrhage rate.
Hydrogen—Deuterium Exchange in Bovine Serum Albumin Protein Monitored by Fourier Transform Infrared Spectroscopy, Part I: Structural Studies
Authors: Grdadolnik Jože , Maréchal Yves
Published: November 2005

The structure of the amide I band of bovine serum albumin (BSA) was determined using an H/D exchange experiment. The difference between the dry and hydrated exchange spectrum revealed the fine structure of the amide I band. The band at 1717 ± 2 cm−1 is due to the vibration of the COOH moieties from the protein side chains. Band components at 1682 ± 2 cm−1, 1655 ± 2 cm−1, and 1637 ± 2 cm−1 are assigned to the vibrations of the backbone C=O. These three bands belong to vibrations of three different populations of amide groups differing in the number of established H-bonds. The connectivity between the frequencies of various amide vibrations was determined by two-dimensional generalized correlation spectroscopy and spectral decomposition. About 7% of the whole exchangeable hydrogen atom population (NH, NH2, and OH groups from backbone and side chains) remains unexchanged, and these hydrogen atoms belong mainly to the NH groups, which are H-bonded to specific C=O groups. Moreover, this study concerns the approximately 10% of hydrogen atoms belonging to a particular HN … OC population with a characteristic amide A frequency at 3290 cm−1 and an amide I band at 1655 ± 2 cm−1, usually attributed to the α-helical structure that remains unexchanged. At higher temperature the exchange is more efficient. Upon heating, a further 4% of these NH groups are deuterated. The comparison of the exchange spectrum at higher temperature with the structural changes of the protein at the same temperature implies that the change in overall dynamics of the protein improve the level of exchange.
Partial Least Squares Based Decomposition of Five Spectrally Overlapping Factors
Authors: Pomerleau-Dalcourt Natalie , Weersink Robert , Lilge Lothar
Published: November 2005

The development of a multi-sensory fiber-optic based fluence rate probe (MSP) for light monitoring and dosimetry during photodynamic therapy (PDT) created the need for a robust multivariate signal analysis algorithm capable of quantifying the intensity of five component spectra, representing the sensors, which display a large degree of spectral overlap. Partial least squares (PLS) analysis, as an option for such an analysis algorithm, was evaluated through simulations in the presence of three types of noise, which experimentally may limit the accuracy of PLS quantification of component spectra contributions. Random, or white noise, background was varied over a range of 0–15% relative intensity. A non-random (Gaussian) background vector was simulated, as an experimentally relevant spectral interferent, over a range of 0–7% relative intensity. Spectral variation was modeled by a spectral shift of ±1–5 nm. Procedures for selecting preferred combinations of fluorophores, with minimum possible spectral overlap, were developed. To illustrate the importance of this selection process, PLS performance results were compared for two possible combinations of five fluorophores, as well as for the combination of three fluorophores currently in experimental use with MSPs. Experimentally anticipated worst-case quantifications were identified for all three types of simulated noise (5% random background, 0.5% Gaussian background, and ±2 nm spectral shift). The effects of single and combined types of noise were evaluated by independently varying each type of simulated noise over the experimentally relevant range. The mean percentage error in determining the fluorophore contributions and hence quantification of the fluence rate were compared with the required performance standard of better than 10% error for optical power meters in medical use. The PLS algorithm provided an accuracy of 7 ± 2% for five fluorophores and 3.3 ± 0.8% for three fluorophores, indicating that PLS is an appropriate choice for this application.
Observation of Large Photoacoustic Signal Phase Changes during a Diffusion Process
Authors: Bajic Stanley J. , Jones Roger W. , McClelland John F.
Published: November 2005

The phase of the photoacoustic signal is known to be a sensitive and accurate means to investigate, both qualitatively and quantitatively, static multilayer heterogeneous systems. According to theory, the maximum phase delay for a very weakly absorbing homogeneous sample should be within 45° of a very strongly absorbing sample, while for heterogeneous samples the phase delay can be greater than 45°. Here we report the observation of photoacoustic phase delays greater than 350° by extending the use of step-scan phase modulation photoacoustic spectroscopy to study a non-repetitive dynamic system in situ, in real time. These large phase delays correspond to sampling several thermal diffusion lengths into the sample. The model system used in this study consisted of a hydrocarbon grease diffusing through a porous Teflon film. The progress of the diffusion was tracked by monitoring both the photoacoustic signal magnitude and the phase of the hydrocarbon grease after isolation from the Teflon film signal contributions at two different phase modulation frequencies.
Multicomponent Peak Modeling of Protein Secondary Structures: Comparison of Gaussian with Lorentzian Analytical Methods for Plant Feed and Seed Molecular Biology and Chemistry Research
Authors: Yu Peiqiang
Published: November 2005

The objective of this study was to compare Gaussian and Lorentzian multicomponent peak modeling methods in quantification of protein secondary structures of various plant seed and feed tissues within intact tissue at a cellular and subcellular level using the advanced synchrotron light sourced Fourier transform infrared (FT-IR) microspectroscopy (S-FTIR). This experiment was performed at the beamline U10B at the National Synchrotron Light Source (NSLS) in Brookhaven National Laboratory (BNL), U.S. Dept of Energy (NSLS-BNL, NY). The results show that in the comparison of the Gaussian and Lorentzian multi-peak modeling methods, the Gaussian method is more accurate for fitting multi-peak curves of protein secondary structures than the Lorentzian method, with higher modeling R2 values (0.92 versus 0.89, P < 0.05). There were no large differences ( P > 0.05) in the quantification of the relative percentage of α-helices, β-sheets, and others in protein secondary structures of the plant seed tissues, with averages of 30.2%, 40.4%, and 29.4%, respectively. However, there are significant differences ( P < 0.05) in the quantification of the ratios of β-sheet to α-helix (1.42 versus 1.60; SEM = 0.058) in protein secondary structures of the plant seed tissues. With synchrotron FT-IR microspectroscopy, the ultrastructural–chemical makeup and nutritive characteristics could be revealed at a high spatial resolution. Synchrotron-based FT-IR microspectroscopy revealed that the secondary structure of protein differed between the plant seed tissues in terms of relative percentage and ratio of protein secondary structures (α-helix and β-sheet) within cellular dimensions. The results also show that the flaxseed tissues contained higher ( P < 0.05) percentage of α-helix (38.6 versus 24.0%) and β-sheet (45.3 versus 36.9%), lower ( P < 0.05) percentage of other secondary structures (16.1% versus 39.0%), and higher ( P < 0.05) ratios of α-helix to β-sheet (0.90 versus 0.69) than the winterfat seed tissues. It must be mentioned that the relative percentages of protein secondary structure may not reflect the true secondary structure. However, the purpose of modeling the relative percentage of secondary structure was to detect the variety of differences among seed/feed/plant tissues and their relation to nutritive value and digestive behavior. The results demonstrate the potential of highly spatially resolved synchrotron-based FT-IR microspectroscopy to reveal protein secondary structures of the plant seed/feed tissues. Further study is needed to quantify the relationship between protein secondary structures and nutrient availability and digestive behavior of various varieties of plant seed tissues. Information from the infrared probing of protein secondary structures can be valuable as a guide to maintaining protein nutritive value and quality for animal and human use.
Off-Line Direct Deposition Gas Chromatography/Surface-Enhanced Raman Scattering and the Ramifications for On-Line Measurements
Authors: Heaps David A. , Griffiths Peter R.
Published: November 2005

Surface-enhanced Raman spectra (SERS) of molecules separated by gas chromatography (GC) were measured off-line by condensing the analyte on a moving, liquid-nitrogen-cooled ZnSe window on which a 5 nm layer of silver had been formed by physical vapor deposition. After the components that eluted from the chromatograph had been deposited, the substrate was allowed to warm up to room temperature and transferred to the focus of a Raman microspectrometer where the spectrum of each component was measured. Band intensities in the spectrum of 3 ng of caffeine prepared in this way were approximately the same as in the spectrum of bulk caffeine. By making some logical assumptions, it was shown that identifiable GC/SERS spectra of 30 pg of many molecules could be measured over a 300 cm−1 region in real-time and that if an optimized substrate were used the minimum identifiable quantity could be reduced to 1 pg or less.
Near-Infrared Combination and Overtone Bands of CH in CHX3, CHX2—CHX2, and CHX2—CX2—CHX2
Authors: Iwamoto Reikichi , Nara Akishi , Matsuda Toshihiko
Published: November 2005

In the present report we studied spectral characteristics of the near-infrared combination and overtone bands of CH vibrations of a CH sequence. The near-infrared bands of the CH in CHX3 (X, halogen), which were interpreted in terms of the CH stretching and CH deformation fundamentals without any ambiguity, typically showed how the frequency and intensity of a combination or an overtone depend on the vibrational excited state. In the CH–C–CH of CHX2CX2CHX2, the vibrations of one CH are isolated from those of the other CH, and the combination and overtone bands were similarly interpreted as those of the CH, although each of the combination bands was split into two because of non-degeneracy of the CH deformation. In the CH–CH of CHX2CHX2, the CH deformations only have coupled modes. The first combination showed four narrowly separate bands, which were reasonably interpreted on the basis of the CH stretching and the coupled CH deformation modes. We demonstrated that the first combination of coupled modes as well as the combination of up to, at least, the third order of isolated modes have the nature of the characteristic bands.