bluuebunny/crossref_metadata_2025 huggingface dataset:
Pulsed photoacoustic calibration of a differential absorption water vapor lidar
Authors: Dentamaro Anthony V. , Dao Phan D.
Published: June 2003

We have designed and constructed a photoacoustic (PA) cell to be used for wavelength calibration in a water vapor differential absorption lidar (DIAL) system. This system will be used to remotely determine atmospheric H2O16 concentrations. The accuracy of these measurements depends critically on the ability to tune to and detune from lines in the water vapor spectrum. Specifically, the signal-to-noise ratio of the PA signal must be strong enough to locate the center frequency of an absorption line with accuracy and repeatability better than 0.2 times the Lorentzian half width of the absorption (0.1 cm−1). So, although it represents only a peripheral part of the DIAL experiment, the calibration provided by the PA cell is critical to its overall success. In the environment of a mobile lidar system, problems with mechanical and electronic noise are potentially greater than those in a typical laboratory setting, and the cell is designed to address this situation. The PA cell utilizes a “figure-8” beam tunnel geometry which partially separates the tunnel into two subchambers, each with a microphone mounted in it. The laser beam is allowed to pass through only one of these subchambers. The microphone in the side that receives the laser beam records both PA signal and background noise, while the other microphone records only background noise. A differential lowpass filter and microphone amplifier circuit, of a design dedicated to this application, uses the output of the two microphones to subtract the background noise from the PA signal. The PA cell described within is of simple mechanical design and is constructed at very little cost.
Obtaining the monodisperse droplets during the gas penetration through a thin liquid film
Authors: Kontush S. M. , Rybak S. S. , Bekshaev A. Ya. , Esen C. , Schweiger G.
Published: June 2003

The principle of monodisperse aerosol generation based on spraying liquid during the gas bubble destruction near the liquid surface is considered. The synchronization of the bubble growth and collapse processes with capillary oscillations of the thin liquid film is proposed to provide the stability and reproducibility of the droplet formation conditions. On this basis, the possibility of creating the streams of nearly identical droplets without external periodic stimulation is shown. In essence, they can be realized in very wide conditions and only demand a source of low pressure for their implementation. Simple constructions of the monodisperse droplet generator and its operation modes are described.
A multilayer edge-on single photon counting silicon microstrip detector for innovative imaging techniques in diagnostic radiology
Authors: Olivo A. , Pani S. , Dreossi D. , Montanari F. , Bergamaschi A. , Vallazza E. , Arfelli F. , Longo R. , Rigon L. , Castelli E.
Published: June 2003

A three-layer detector prototype, obtained by stacking three edge-on single photon counting silicon microstrip detectors, has been developed and widely tested. This was done in the framework of the Synchrotron Radiation for Medical Physics/Frontier Radiology (SYRMEP/FRONTRAD) collaboration activities, whose aim is to improve the quality of mammographic examinations operating both on the source and on the detector side. The active surface of the device has been fully characterized making use of an edge-scanning technique and of a well-collimated laminar synchrotron radiation beam. The obtained data (interlayer distances, channel correspondence, etc.) have then been used to combine information coming from each detector layer, without causing any loss in spatial and contrast resolution of the device. Contrast and spatial resolution have also been separately evaluated for each detector layer. Moreover, imaging techniques (phase contrast, refraction, and scatter imaging), resulting in an increased visibility of low absorbing details, have been implemented, and their effectiveness has been tested on a biological sample. Finally, the possibility of simultaneously acquiring different kind of images with the different detector layers is discussed. This would result in maximizing the information extracted from the sample, while at the same time the high absorption efficiency of the detector device would allow a low dose delivery.
Optical absorption and electronic structure of Zn1−xMnxO alloys studied by spectroscopic ellipsometry
Authors: Kim Kwang Joo , Park Young Ran
Published: June 2003

Dielectric functions of Zn1−xMnxO (x⩽0.19) thin films were obtained by spectroscopic ellipsometry at room temperature in the 1.5–5 eV photon energy region. A strong absorption structure is observed near 3.1 eV, below the optical band-gap absorption (E0) edge, and it does not shift with x. It is interpreted as due to transitions between the crystal-field-split 3d5 multiplet levels of the tetrahedral Mn2+ ion that substitute for Zn2+. A redshift is observed for the E0 edge near x=0.06 from that of pure ZnO, interpreted as due to the spin–exchange interaction between d electrons of the Mn2+ ion and sp electrons near the band gap. The E0 edge shows a blueshift for larger x. The excitonic character of the E0 edge is gradually reduced and replaced by a three-dimensional shape as x increases, and this is attributed to increased disorder.
Unified compact model for the ballistic quantum wire and quantum well metal-oxide-semiconductor field-effect-transistor
Authors: Jiménez D. , Sáenz J. J. , Iñı́quez B. , Suñé J. , Marsal L. F. , Pallarès J.
Published: June 2003

We present a compact model based on the Landauer transmission theory for the silicon quantum wire and quantum well metal-oxide-semiconductor field effect transistor (MOSFET) working in the ballistic limit. This model captures the static current-voltage characteristics in all the operation regimes, below and above threshold voltage. The model provides a basic framework to account for the electronic transport in MOSFETs, being easily adaptable to gate structures such as the double-gate or gate-all-around. Numerical simulations based on the proposed model have been compared with experiments and quantum mechanical self-consistent simulations, with good agreement.
Near-infrared phase cancellation instrument for fast and accurate localization of fluorescent heterogeneity
Authors: Chen Yu , Mu Chenpeng , Intes Xavier , Blessington Dana , Chance Britton
Published: June 2003

Near-infrared (NIR) diffuse optical imaging has become a promising method for noninvasive in vivo detection of breast cancer with intrinsic chromophores. Recent developments in molecular specific targeting fluorescent contrast agents offer high tumor to normal tissue contrast, and are capable of selectively labeling various precancer/cancer signatures, thus enhancing both the sensitivity and specificity of cancer detection. To detect a subsurface tumor labeled by fluorescent contrast agents, we have developed a phase cancellation imaging system for fast localization of fluorescent object embedded several centimeters deep inside the turbid media. The instrument is a frequency domain (50 MHz) phase modulation system with dual out-of-phase sources. The excitation wavelength is 780 nm and the fluorescence photons are collected through an 830±10 nm band-pass filter. Localization of fluorescent objects inside the scattering media is accurate using a phase cancellation device. The localization error for a 5 mm diameter sphere filled with 1 nanomole fluorescent dye and 3 cm deep inside the turbid media is about 2 mm. The accuracy of the localization suggests that this system could be helpful in guiding clinical fine-needle biopsy, and would benefit the early detection of breast tumors.
High power spectrometer for the characterization of photovoltaic cells in a controlled atmosphere or vacuum
Authors: Krebs Frederik C. , Jørgensen Mikkel
Published: June 2003

The complete description of a high power spectrometer, allowing for large area illumination of up to 10 cm2 in the wavelength range 200–800 nm with average power densities of 2 mW cm2, is provided. The setup employs a stationary 150 W xenon lamp used in conjunction with a simple stationary single monochromator grating. The photovoltaic sample under test is placed in a stainless-steel vacuum chamber allowing for operating pressures down to 10−6 mbar equipped with a quartz window and electrical connections. The entire vacuum chamber was placed on a moving arm allowing for positioning in a selected part of the diffracted beam of the monochromator. The typical spectral resolution was 12 nm cm−1 which gave bandwidths of 25 nm with a 2 cm sample width. The electrical characteristics of the photovoltaic device under test was measured using a source meter giving an experimental current sensitivity of 10 pA. We finally demonstrate the application of the instrumental setup for the characterization of a polymer based photovoltaic.
Thermal stability of the magnetization following thermomagnetic writing in perpendicular media
Authors: Lyberatos A. , Guslienko K. Yu
Published: June 2003

The thermal decay of the magnetization in granular thin films with high perpendicular anisotropy following thermomagnetic writing is investigated using a semianalytical and a numerical mean-field self-consistent model. We study the effects of cooling rate, dispersions in grain volumes and anisotropy fields, damping, and intergranular interactions. Two distinct contributions to the thermal decay arise from cooling and storage, respectively. The magnetization freezes during cooling as a result of the increase in anisotropy and the net thermal decay for slow cooling is logarithmically dependent on the time before the magnetization is frozen. The areal density advantage of heat-assisted, over conventional magnetic recording increases sharply when the thermal decay starts close to the Curie temperature. The maximum benefits of heat-assisted recording using FePt media are derived by heating above the Curie temperature.
Field-induced cation migration in Cu oxide films by in situ scanning tunneling microscopy
Authors: Singh J. P. , Lu T.-M. , Wang G.-C.
Published: June 2003

We observed the formation of Cu metallic nanoscale structures of ∼20-nm diameter and ∼2-nm height on a Cu2O covered polycrystalline Cu film under an applied field using a scanning tunneling microscope tip in a high vacuum condition. We interpreted the results as the Cu cation transport through the copper oxide film towards the surface when a positive biased voltage (>1.5 V) was applied to the film to lower the activation energy of the cation migration. Scanning tunneling spectroscopy measurements showed that the field-induced nanostructures were pure metallic Cu with a characteristic broad peak near −0.45 eV. No structural change was observed when a negative bias was applied to the film.
Experimental determination of electron and hole mean drift distance: Application to chemical vapor deposition diamond
Authors: Marinelli Marco , Milani E. , Pucella G. , Tucciarone A. , Verona-Rinati G. , Angelone M. , Pillon M.
Published: June 2003

A simple technique for measuring the electron and hole mean drift distance in chemical vapor deposition polycrystalline diamond in the as-grown and in the so-called pumped state obtained by 90Sr β-particle irradiation is presented. To this purpose, the efficiency η of a diamond-based particle detector was measured using a 5.5-MeV 241Am α-particle source. In particular, two different experimental setups were specifically designed and realized in order to perform a systematic study of the device efficiency as a function of the α-particle penetration depth, both in the positive and negative bias polarization. In the first setup, air is used as an absorbing layer in order to change the energy of the impinging α particles, while in the second one, the measurements were performed in vacuum and the incidence angle was varied in the 0°–80° range. The advantages of the latter setup are evidenced. The theoretical formula for the mean drift distances of carriers is derived using a properly modified Hecht model, and fitted to the data, allowing a separate evaluation of the charge collection distances of each carrier type (λe=μeτeE and λh=μhτhE). The obtained results unambiguously show that the pumping process is much more effective on hole conduction, λh being much greater than λe in the pumped state.
Modification of the spontaneous emission of CdTe nanocrystals in TiO2 inverted opals
Authors: Solovyev V. G. , Romanov S. G. , Sotomayor Torres C. M. , Müller M. , Zentel R. , Gaponik N. , Eychmüller A. , Rogach A. L.
Published: June 2003

A light source in a three-dimensional photonic crystal has been realized by depositing CdTe nanocrystals on the inner surface of TiO2 inverted opal films. Two effects, the photonic band gap of inverted opal and the energy exchange between CdTe nanoparticles and the TiO2 framework, have been identified as major sources of emission spectrum modification. An analysis of input-output characteristics of the spontaneous emission demonstrates the saturation of the excitation-to-emission conversion in the emission band and the conversion efficiency improvement associated with the presence of the photonic band gap.
Vertical nanowire transistor in flexible polymer foil
Authors: Chen Jie , Könenkamp R.
Published: June 2003

Fabrication and operation of a vertical nanowire field-effect transistor is reported. The device is prepared by growing vertical wires in the cylindrical pores of a polymer foil stack. The nanowire diameter is approximately 100 nm, the packing density up to 108 cm−2. The polymer foil stack consists of two polymer layers and an intermediate metal layer. Cylindrical holes are prepared in this stack by using fast ion irradiation and subsequent etching. Well-defined cylindrical openings with diameters between 50 and 150 nm are obtained. The semiconductor growth involves electrodeposition of the p-type quaternary compound CuSCN. Electrical measurements on first devices show transistor action with some gate leakage, which may be improved in future designs. The arrangement of inorganic device material embedded in soft polymer matrix is structurally robust, and the devices show low sensitivity to mechanical strain of the foil. Single electron effects may be expected in these devices, when the dimensions are further reduced.
Spatially direct and indirect transitions observed for Si/Ge quantum dots
Authors: Larsson M. , Elfving A. , Holtz P. O. , Hansson G. V. , Ni W.-X.
Published: June 2003

The optical properties of Ge quantum dots embedded in Si were investigated by means of photoluminescence, with temperature and excitation power density as variable parameters. Two different types of recombination processes related to the Ge quantum dots were observed. A transfer from the spatially indirect to the spatially direct recombination in the type-II band lineup was observed with increasing temperature. A blueshift of the spatially indirect Ge quantum-dot-emission energy with increasing excitation power is ascribed to band bending at the type-II Si/Ge interface for high carrier densities. Comparative studies were performed on uncapped Ge dot structures.
The effect of additional oxidation on the memory characteristics of metal-oxide-semiconductor capacitors with Si nanocrystals
Authors: Garrido B. , Cheylan S. , González-Varona O. , Pérez-Rodrı́guez A. , Morante J. R.
Published: June 2003

Metal-oxide-semiconductor (MOS) capacitors with Si nanocrystals (Si-nc) obtained by ion implantation in SiO2 have been studied for nonvolatile memory applications. The use of a thermal oxide and the accurate tuning of the postimplantation processing conditions allow good integrity, reliability, and high retention times. We propose an additional thermal oxidation step after the formation of the Si-nc. This process has enabled growing a thin tunnel oxide at the Si/SiO2 interface completely free of Si-nc and Si excess, leading to a formidable increase of the retention time. In addition the additional oxidation makes it possible to control the size and density of Si-nc. Finally, we show its impact on the memory characteristics of the nanocrystal device (writing speed and programming window).
Resonance transmission modes in dual-periodical dielectric multilayer films
Authors: Qin Q. , Lu H. , Zhu S. N. , Yuan C. S. , Zhu Y. Y. , Ming N. B.
Published: June 2003

The resonance transmission modes with high-quality factors may generate in a one-dimensional dual-periodic photonic band-gap structure. The frequency, frequency interval, and number of these modes can be tuned as desired by adjusting its structural parameters. In this letter, we report the experimental and theoretical results on dual-periodical TiO2/SiO2 multilayer films. With perfect transmission and mode controllability, this structure opens a promising way to fabricate multiwavelength filters for future dense wavelength division application.
Influence of coupling effect in the operation of vertically coupled quantum-dot lasers
Authors: Shi B. , Xie Y. H.
Published: June 2003

The influence of the coupling effect in the operation of vertically coupled quantum-dot lasers is studied by solving coupled rate equations including the terms representing carrier coupling between vertically stacked quantum dots. The calculation results show a much narrower spectral width above the lasing threshold compared with the uncoupled case. The single-mode output power is also enhanced by the coupling effect, especially when there is a large fluctuation in dot size.
A highly glass-forming alloy with low glass transition temperature
Authors: Zhao Z. F. , Zhang Z. , Wen P. , Pan M. X. , Zhao D. Q. , Wang W. H. , Wang W. L.
Published: June 2003

A rare-earth Pr-based bulk metallic glass (BMG) is obtained in the shape of rod up to 5 mm in diameter by die cast. Unlike other rare-earth-based BMGs, it exhibits a distinct glass transition, the low glass transition temperature (Tg=409 K), a large and stable supercooled liquid region, and paramagnetic property. The glass transition as well as its kinetic nature and the fragility parameters of the BMG have been studied. The BMG offers an ideal model to investigate the nature of glass transition as well as the relaxation and nucleation with a large experimentally accessible time and temperature window at low temperatures.
InAs/InP quantum dots in SiO2/Ta2O5-based microcavities
Authors: Dalacu D. , Poitras D. , Lefebvre J. , Poole P. J. , Aers G. C. , Williams R. L.
Published: June 2003

Planar InAs/InP quantum-dot microcavities using multilayer SiO2/Ta2O5 Bragg reflectors have been studied in emission. For an eight-pair mirror design, the stop band extends from 700 to 900 meV and the cavity linewidth is ∼500 μeV for emission at 850 meV. Measurements as a function of incident power show quantum-dot saturation behavior, with the emission intensity going to the wetting layer outside the cavity stop band. Saturation behavior at fixed pump power is also observed as a function of decreasing temperature. Dispersion measurements as a function of emission angle show polarization splitting in reasonable agreement with theory.
Josephson effect in high-Tc La2−xSrxCuO4/La2−xSrxCuO4 ramp-edge junctions
Authors: Haibara H. , Iguchi I.
Published: June 2003

The observation of Josephson effect in high-Tc La2−xSrxCuO4/La2−xSrxCuO4 (LSCO/LSCO) ramp-edge junctions is reported. The LSCO/LSCO ramp-edge junctions are fabricated by pulsed laser deposition, Ar ion milling, and photolithography techniques adopting an interface-engineered process. The fabricated junctions have the maximum Josephson current Ic of a few hundred microamperes and clear Shapiro steps are observable under microwave irradiation. The modulation of Ic under an external magnetic field is also recognized.
Ca2+ Sparks and Embers of Mammalian Muscle. Properties of the Sources
Authors: Zhou J. , Brum G. , González A. , Launikonis B.S. , Stern M.D. , Ríos E.
Published: June 2003

Ca2+ sparks of membrane-permeabilized rat muscle cells were analyzed to derive properties of their sources. Most events identified in longitudinal confocal line scans looked like sparks, but 23% (1,000 out of 4,300) were followed by long-lasting embers. Some were preceded by embers, and 48 were “lone embers.” Average spatial width was ∼2 μm in the rat and 1.5 μm in frog events in analogous solutions. Amplitudes were 33% smaller and rise times 50% greater in the rat. Differences were highly significant. The greater spatial width was not a consequence of greater open time of the rat source, and was greatest at the shortest rise times, suggesting a wider Ca2+ source. In the rat, but not the frog, spark width was greater in scans transversal to the fiber axis. These features suggested that rat spark sources were elongated transversally. Ca2+ release was calculated in averages of sparks with long embers. Release current during the averaged ember started at 3 or 7 pA (depending on assumptions), whereas in lone embers it was 0.7 or 1.3 pA, which suggests that embers that trail sparks start with five open channels. Analysis of a spark with leading ember yielded a current ratio ranging from 37 to 160 in spark and ember, as if 37–160 channels opened in the spark. In simulations, 25–60 pA of Ca2+ current exiting a point source was required to reproduce frog sparks. 130 pA, exiting a cylindric source of 3 μm, qualitatively reproduced rat sparks. In conclusion, sparks of rat muscle require a greater current than frog sparks, exiting a source elongated transversally to the fiber axis, constituted by 35–260 channels. Not infrequently, a few of those remain open and produce the trailing ember.
Characteristic substructures and properties in chemical
carcinogens studied by the cascade model
Authors: Okada Takashi
Published: June 2003

Motivation: Chemical carcinogenicity is an important subject in health and environmental sciences, and a reliable method is expected to identify characteristic factors for carcinogenicity. The predictive toxicology challenge (PTC) 2000–2001 has provided the opportunity for various data mining methods to evaluate their performance. The cascade model, a data mining method developed by the author, has the capability to mine for local correlations in data sets with a large number of attributes. The current paper explores the effectiveness of the method on the problem of chemical carcinogenicity.

Results: Rodent carcinogenicity of 417 compounds examined by the National Toxicology Program (NTP) was used as the training set. The analysis by the cascade model, for example, could obtain a rule ‘Highly flexible molecules are carcinogenic, if they have no hydrogen bond acceptors in halogenated alkanes and alkenes’. Resulting rules are applied to predict the activity of 185 compounds examined by the FDA. The ROC analysis performed by the PTC organizers has shown that the current method has excellent predictive power for the female rat data.

Availability: The binary program of DISCAS 2.1 and samples of input data sets on Windows PC are available at http://www.clab.kwansei.ac.jp/mining/discas/discas.html

Supplementary information: Summary of prediction results and cross validations is accessible via http://www.clab.kwansei.ac.jp/~okada/BIJ/BIJsupple.htm Used rules and the prediction results for each molecule are also provided.

Contact: okada-office@ksc.kwansei.ac.jp
A Bayesian network approach to operon prediction
Authors: Bockhorst Joseph , Craven Mark , Page David , Shavlik Jude , Glasner Jeremy
Published: June 2003

Motivation: In order to understand transcription regulation in a given prokaryotic genome, it is critical to identify operons, the fundamental units of transcription, in such species. While there are a growing number of organisms whose sequence and gene coordinates are known, by and large their operons are not known.

Results: We present a probabilistic approach to predicting operons using Bayesian networks. Our approach exploits diverse evidence sources such as sequence and expression data. We evaluate our approach on the Escherichia coli K-12 genome where our results indicate we are able to identify over 78% of its operons at a 10% false positive rate. Also, empirical evaluation using a reduced set of data sources suggests that our approach may have significant value for organisms that do not have as rich of evidence sources as E.coli.

Availability: Our E.coli K-12 operon predictions are available at http://www.biostat.wisc.edu/gene-regulation

Contact: joebock@biostat.wisc.edu

* To whom correspondence should be addressed.
Auditing managerial training needs of Turkish small and medium‐sized hotel enterprises
Authors: Avcikurt Cevdet
Published: June 2003

The number and importance of small and medium‐sized hotel enterprises (SMHEs) is increasing. As in many countries, SMHEs in Turkey play a great role in the economy, due to their significant share within the tourism industry in terms of number of enterprises, employment and investment. SMHEs accommodate a significant part of foreign and domestic visitors, especially in coastal areas. Therefore, the management of those establishments needs to be investigated. This article focuses on perceived training needs of the owner‐managers of the small and medium‐sized hotel establishments in a Turkish tourist town, Bodrum, on the Aegean coast and examines the impact of the current situation on the management practices. The findings indicate that the training level of the SMHEs at the managerial level is not satisfactory. This prevents the managers being successful in management and productive hotel operations. General outcomes can be drawn for hotel operators and tourism policy makers.
Middle East expansion – the case of Debenhams
Authors: Jones Glynis
Published: June 2003

The Middle East is currently proving an attractive destination for retailers, with many sectors now being represented in the region’s markets. This case considers the opportunities and threats presented by the Middle East environment and outlines the expansion of UK department store Debenhams in the region. With franchise partner M&H Alshaya, it now has six stores in the region, with further openings planned.
Distribution of Danish potted plants
Authors: Jørgensen Niels
Published: June 2003

Presents a case on Danish potted plants distribution. The company, GASA‐Group Denmark, is the dominating distributor of Danish potted plants to all of Europe with a total turnover of approximately DKK2.8 billion. The company’s management is planning a long‐term strategy, and the paper describes the strategic challenges to be met, and the available basis for decision. As the company is owned by the Danish market gardeners, it is important that the company decides whether or not to release itself from this group of suppliers. Another important problem is if the company’s basis of existence will decrease because of the customers’ and the suppliers’ structural development
Breathlessness clinics within specialist palliative care settings can improve the quality of life and functional capacity of patients with lung cancer
Authors: Hately Juliet , Laurence Virginia , Scott Ann , Baker Roger , Thomas Peter
Published: June 2003

This paper is a development on recent research that proved the value of nonpharmacological techniques and strategies in the management of breathlessness in lung cancer. It evaluates the intervention in a specialist palliative care setting using an outpatient clinic at Lewis-Manning House. Referrals were made by the patients' physician or specialist nurse. Patients ( n=30) were assessed and treated by the senior physiotherapist in charge of the clinic over three sessions. A number of outcomes were measured at various stages of the patients' treatment. The results have confirmed and strengthened the previous published results. Highly significant improvements in patients' breathlessness, functional capacity, activity levels and distress levels have been shown. For example, the percentage of patients experiencing breathlessness several times or more per day was reduced from 73% to 27% four weeks later. In addition, this project has been able to demonstrate significant improvements in quality of life and high levels of satisfaction with the interventions. Qualitative data enhanced the findings of objective measurements.
Factors influencing constipation in advanced cancer patients: a prospective study of opioid dose, dantron dose and physical functioning
Authors: Bennett Mike , Cresswell Helen
Published: June 2003

The relationship between opioid dose, dantron dose, bowel function and physical functioning (measured with the modified Barthel Index) was determined in a sample of 50 inpatients with advanced cancer. Data were collected prospectively from chart review and patient interviews one week after admission to allow for protocol-driven management of constipation to be established. Bowel scores were significantly reduced in 35 patients treated with opioids compared with 15 patients not treated with opioids. Within the opioid group, however, there was no relationship between opioid dose, bowel score, dantron dose or Barthel Index. Higher doses of dantron were associated with better physical functioning (but not opioid dose) suggesting that for any given dose of opioid, fitter patients were treated with larger doses of laxatives. Factors other than opioid dose and physical functioning may be more important in contributing to constipation in this group of patients. Less potent opioid drugs, such as codeine, are just as likely to cause constipation as more potent opioids.
Health professionals' views on advance directives: a qualitative interdisciplinary study
Authors: Thompson Trevor DB , Barbour Rosaline S , Schwartz Lisa
Published: June 2003

The aim of this study was to discover the views of health professionals in the Greater Glasgow area on advance directives, using semi-structured interviews and focus groups. The twelve participants interviewed included four hospital doctors, four general practitioners (GPs) and four nurses. The six focus groups comprised hospice nurses, GPs, consultant geriatricians, geriatricians in training grades and an interdisciplinary group. Participants were purposively selected to reflect a range of personal experiences with, and attitudes toward, the advance directive using key informants and a short questionnaire. Participants were asked to comment on a specially constructed sample advance directive. All research encounters were recorded, transcribed and analysed using accepted methods in qualitative research. The advance directive was seen as a means of promoting peace of mind in will makers, of allowing carers to honour the patients' wishes and of stimulating communication between all parties. Conversely the advance directive was seen as generating certain risks for the will maker – including those of coercion, misunderstanding, paradoxical overintervention and inadvertent undertreating. A core concern surrounded the issue of ‘informedness’ in will makers and the ethics of deciding for a future demented self.
Use of routinely collected data on psychiatric in-patient care
Authors: Glover Gyles
Published: June 2003

Since the start of the National Health Service, data have been collected on admissions to psychiatric in-patient units, first as the Mental Health Enquiry, then as part of Hospital Episode Statistics. Some details have changed but many have stayed remarkably consistent. Published literature on the wide range of research and policy work undertaken using this data source is reviewed. Early work was central to the government's deinstitutionalisation policy in the early 1960s. Subsequent studies cover a wide range of epidemiological and health services research issues. A new statistical base, the Mental Health Minimum Data Set, covering individuals receiving all types of health care is currently being set up. This will supplement (but not replace) admission statistics.
Attendance at the accident and emergency department in the year before suicide: Retrospective study
Authors: Gairin Isaura , House Allan , Owens David
Published: June 2003

Background

The National Confidential Inquiry into suicides in England and Wales found that a quarter of suicides are preceded by mental health service contact in the year before death. However, visits to accident and emergency departments due to self-harm may not lead to a record of mental health service contact.

Aims

To determine the proportion of suicides preceded by accident and emergency attendance in the previous year.

Method

We obtained the list of probable suicides in Leeds for a 38-month period, and examined the records from thecity's accident and emergency departments for a year before each death.

Results

Eighty-five (39%) of the 219 people who later died by suicide had attended an accident and emergency department in the year before death, 15% because of non-fatal self-harm. Final visits dueto self-harm were often shortly before suicide (median 38 days), but the National Confidential Inquiry recorded about a fifth of them as‘not in contact’ with local mental health services.

Conclusions

Although many suicides are preceded by recent attendance at accident and emergency departments due to non-fatal self-harm, local mental health service records may show no recent contact. Suicide prevention might be enhanced were accident and emergency departments and mental health services to work together more closely.
Suicide and attempted suicide among people of Caribbean origin with psychosis living in the UK
Authors: McKenzie K. , Van Os J. , Samele C. , Van Horn E. , Tattan T. , Murray Robin
Published: June 2003

Background

A report from a 1980s cohort claimed that suicidal behaviour was four times less common in UK-resident people of Caribbean origin with psychosis than in British Whites. Since then, evidence has accumulated that the rate of suicide and suicidal ideation has been increasing.

Aims

To compare rates of suicidal behaviour in people of Caribbean and British White origin in a large multi-centre sample of patients with psychosis.

Method

A secondary analysis of 708 patients with psychosis followed up for 2 years. Outcome measures of reported suicide and attempted suicide were adjusted for socio-economic and clinical differences between groups at baseline.

Results

People of Caribbean origin had a lower risk of suicidal behaviour than British Whites (odds ratio adjusted for age and gender 0.49, 95% C1 0.26–0.92). There was a strong negative interaction between ethnic group and age: suicidal acts were four times less likely in people of Caribbean origin aged over 35 years compared with British Whites, but there was no large or significant difference in those under 35.

Conclusions

The previously reported lower relative risk of suicidal behaviour in people of Caribbean origin with psychosis is restricted to those over 35 years, suggesting that the protective effect of Caribbean origin is disappearing in younger generations.
Psychiatrists entering the pharmaceutical industry in the UK
Authors: Aitken Peter , Perahia David , Wright Padraig
Published: June 2003

As a junior doctor, it can be extremely difficult to imagine a working life outside the NHS. Appointment to a consultant post brings some opportunity to practise medicine outside the NHS, but few contemplate a move to an entirely commercial setting. Those of us who have moved to work entirely in a commercial setting, as pharmaceutical physicians, tend to be regarded with a mixture of curiosity and suspicion by our peers and colleagues, who often reveal a great number of misconceptions about our roles and responsibilities. Yet, currently some 731 physicians are registered with the British Association of Pharmaceutical Physicians, with 25 recording psychiatry or neuroscience as their area of expertise. There are 1400 physicians registered on the mailing list for the Faculty of Pharmaceutical Physicians. It was through reflecting on the level of interest as to our motives and rewards that we were moved to write this article. To colleagues in the NHS, it can seem as if we have moved into an unknown and suspect world. This article aims to describe something of the role of the pharmaceutical physician and the initial experience of moving into the industry.
Developing early intervention services in the NHS: a survey to guide workforce and training needs
Authors: Singh Swaran , Wright Christine , Joyce Eileen , Barnes Tom , Burns Thomas
Published: June 2003

Aims and Method

We conducted a questionnaire study to establish the incidence, specialist staff availability, treatment provision and socio-demographic profile of patients with first-episode psychosis referred to all adult and child and adolescent community mental health teams in south and west London.

Results

All 39 teams completed the questionnaire, identifying 295 cases of first-episode psychosis (annual incidence 21/100 000/year) referred in the year 2000. Teams manage to engage most patients with first-episode psychosis. A total of 73% of cases of first-episode psychosis were on some form of Care Programme Approach. However, many teams did not have adequately trained staff to provide psychosocial interventions. Even where such staff were available, care was focused mainly on monitoring medication and risk assessment, with only half the teams providing psycho-educational programmes and only a quarter offering individual cognitive–behavioural therapy to those with first-episode psychosis.

Clinical Implications

Establishing early intervention services nationwide will require significant new resources, including specialist trained staff, which could prove difficult to provide in inner-city areas. Rather than a single, uniform service model, several models of early intervention services based on locally determined need might be more realistic and appropriate, and also allow research into their relative efficacy.
Prognostic Factors in Primary Breast Sarcomas: A Series of Patients With Long-Term Follow-Up
Authors: Zelek L. , Llombart-Cussac A. , Terrier P. , Pivot X. , Guinebretiere J.M. , Le Pechoux C. , Tursz T. , Rochard F. , Spielmann M. , Le Cesne A.
Published: June 2003

Purpose: To describe the pathologic characteristics and prognostic factors of primary breast sarcomas (PBSs).

Patients and Methods: We reviewed the clinical records and pathologic slides of 83 women with PBS treated in our institution between 1954 and 1991, with a median follow-up of 7.8 years. The majority of patients had undergone surgical treatment.

Results: The main histologic type was malignant fibrohistiocytoma (n = 57). For the whole population, the 10-year overall survival (OS) and disease-free survival (DFS) rates were 62% and 50%, respectively. For Fédération Nationale des Centres de Lutte Contre le Cancer grade 1, 2, and 3 tumors, the 10-year OS and DFS rates were 82% and 61%, 62% and 51%, and 36% and 25%, respectively (P = .00007 and .004, respectively). For tumors measuring less than 5 cm, 5 to 10 cm, and more than 10 cm, the 10-year OS and DFS rates were 76% and 66%, 68% and 55%, and 28% and 15%, respectively (P = .002 and .009, respectively). In the multivariate analysis, the tumor size and histologic grade were correlated with the 10-year DFS rate (P = .04 and .01, respectively), but only the histologic grade was correlated with OS (P = .01). Angiosarcoma was the only histologic type significantly associated with a poorer outcome in the multivariate analysis.

Conclusion: PBSs have the same clinical history and prognostic factors as sarcomas arising at other sites. Therefore, it is legitimate to use a similar treatment strategy for PBS as for other sarcomas.
Perceptions of Patients and Physicians Regarding Phase I Cancer Clinical Trials: Implications for Physician-Patient Communication
Authors: Meropol Neal J. , Weinfurt Kevin P. , Burnett Caroline B. , Balshem Andrew , Benson Al B. , Castel Liana , Corbett Sandra , Diefenbach Michael , Gaskin Darrell , Li Yun , Manne Sharon , Marshall John , Rowland Julia H. , Slater Elyse , Sulmasy Daniel P. , Van Echo David , Washington Shakira , Schulman Kevin A.
Published: June 2003

Purpose: To describe and compare the perceptions of cancer patients and their physicians regarding phase I clinical trials.

Methods: Eligible patients had been offered phase I trial participation and had decided to participate but had not yet begun treatment. Each patient’s physician also served as a study subject. Patients and physicians completed questionnaires with domains including perceptions of potential benefit and harm from treatment (experimental and standard), relative value of quality and length of life, and perceived content of patient-physician consultations.

Results: Three hundred twenty-eight patients and 48 physicians completed surveys. Patients had high expectations regarding treatment outcomes (eg, median 60% benefit from experimental therapy), with those choosing to participate in a phase I trial being more optimistic than those declining phase I participation. Patients predicted a higher likelihood of both benefit and adverse reactions from treatment (experimental and standard) than their physicians (P < .0001 for all comparisons). Although 95% of patients reported that quality of life was at least as important as length of life, only 28% reported that changes in quality of life with treatment were discussed with their physicians. In contrast, 73% of physicians reported that this topic was discussed (P < .0001).

Conclusion: Cancer patients offered phase I trial participation have expectations for treatment benefit that exceed those of their physicians. The discordant perceptions of patients and physicians may possibly be explained by patient optimism and confidence; however, the discrepancies in reports of consultation content, particularly given patients’ stated values regarding quality of life, raise the possibility that communication in this context is suboptimal.
Segment polarity and DV patterning gene expression reveals segmental organization of theDrosophilabrain
Authors: Urbach Rolf , Technau Gerhard M.
Published: June 2003

The insect brain is traditionally subdivided into the trito-, deuto- and protocerebrum. However, both the neuromeric status and the course of the borders between these regions are unclear. The Drosophila embryonic brain develops from the procephalic neurogenic region of the ectoderm, which gives rise to a bilaterally symmetrical array of about 100 neuronal precursor cells, called neuroblasts. Based on a detailed description of the spatiotemporal development of the entire population of embryonic brain neuroblasts, we carried out a comprehensive analysis of the expression of segment polarity genes (engrailed, wingless, hedgehog, gooseberry distal,mirror) and DV patterning genes (muscle segment homeobox,intermediate neuroblast defective, ventral nervous system defective) in the procephalic neuroectoderm and the neuroblast layer (until stage 11, when all neuroblasts are formed). The data provide new insight into the segmental organization of the procephalic neuroectodem and evolving brain. The expression patterns allow the drawing of clear demarcations between trito-,deuto- and protocerebrum at the level of identified neuroblasts. Furthermore,we provide evidence indicating that the protocerebrum (most anterior part of the brain) is composed of two neuromeres that belong to the ocular and labral segment, respectively. These protocerebral neuromeres are much more derived compared with the trito- and deutocerebrum. The labral neuromere is confined to the posterior segmental compartment. Finally, similarities in the expression of DV patterning genes between the Drosophila and vertebrate brains are discussed.
Distinct regulators ofShhtranscription in the floor plate and notochord indicate separate origins for these tissues in the mouse node
Authors: Jeong Yongsu , Epstein Douglas J.
Published: June 2003

The establishment of the floor plate at the ventral midline of the CNS is dependent on an inductive signaling process mediated by the secreted protein Sonic hedgehog (Shh). To understand molecularly how floor plate induction proceeds we identified a Shh-responsive regulatory element that directs transgene reporter expression to the ventral midline of the CNS and notochord in a Shh-like manner and characterized critical cis-acting sequences regulating this element. Cross-species comparisons narrowed the activity of the Shh floor plate enhancer to an 88-bp sequence within intron 2 of Shh that included highly conserved binding sites matching the consensus for homeodomain, Tbx and Foxa transcription factors. Mutational analysis revealed that the homeodomain and Foxa binding sites are each required for activation of the Shh floor plate enhancer, whereas the Tbx site was required for repression in regions of the CNS where Shhis not normally expressed. We further show that Shh enhancer activity was detected in the mouse node from where the floor plate and notochord precursors derive. Shh reporter expression was restricted to the ventral (mesodermal)layer of the node in a pattern similar to endogenous Shh. X-gal-positive cells emerging from the node were only detected in the notochord lineage, suggesting that the floor plate and notochord arise from distinct precursors in the mouse node.
Two subunits of theDrosophilamediator complex act together to control cell affinity
Authors: Janody Florence , Martirosyan Zara , Benlali Aude , Treisman Jessica E.
Published: June 2003

The organizing centers for Drosophila imaginal disc development are created at straight boundaries between compartments; these are maintained by differences in cell affinity controlled by selector genes and intercellular signals. skuld and kohtalo encode homologs of TRAP240 and TRAP230, the two largest subunits of the Drosophila mediator complex;mutations in either gene cause identical phenotypes. We show here that both genes are required to establish normal cell affinity differences at the anterior-posterior and dorsal-ventral compartment boundaries of the wing disc. Mutant cells cross from the anterior to the posterior compartment, and can distort the dorsal-ventral boundary in either the dorsal or ventral direction. The Skuld and Kohtalo proteins physically interact in vivo and have synergistic effects when overexpressed, consistent with a skuld kohtalo double-mutant phenotype that is indistinguishable from either single mutant. We suggest that these two subunits do not participate in all of the activities of the mediator complex, but form a submodule that is required to regulate specific target genes, including those that control cell affinity.
Evaluating the effect of generic advertising and food health information within a meat demand system
Authors: Boetel Brenda L. , Liu Donald J.
Published: June 2003

The objective of this article was to disentangle the effect on meat product consumption of generic advertising from that of nonadvertising‐related food health information. Using quarterly data from 1976 to 2000, a linearized Almost Ideal Demand System was estimated for beef, pork, poultry, and fish. Simulation results indicate that the increased food health concerns for fat and cholesterol have resulted in a 6% reduction in the consumption of beef per capita per quarter since 1987, and an 18% increase in the poultry consumption. The results also indicate that there is a significant negative spill‐over effect of beef advertising on pork consumption and vice versa. However, a positive spill‐over effect of pork advertising on poultry consumption is also identified. [Econlit citations: D120, Q110, Q130]. © 2003 Wiley Periodicals, Inc. Agribusiness 19: 345–354, 2003.
Characteristic properties of polypropylene cationic fabrics and their derivatives
Authors: Mosleh S. , Gawish S. M. , Sun Yuyu
Published: June 2003

Polypropylene fabrics were modified with 2N‐morpholino ethyl methacrylate by electron beams and grafting. Then, the modified fabrics were quaternized with different alkylating agents, such as benzyl chloride, monochloroacetic acid, chlorosulfonic acid, and chloroethanol. The reaction completion was calculated from the increase in the fabric weight. The modified polypropylene fabrics were characterized by microanalysis and IR spectroscopy. The moisture regain was measured at 20°C and 65% relative humidity. The modified fabrics were sufficiently hydrophilic to adsorb the metal ion Cu2+ from a CuSO4 solution. Their antimicrobial properties were evaluated. © 2003 Wiley Periodicals, Inc. J Appl Polym Sci 89: 2917–2922, 2003