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Background: The Warfarin-Aspirin Symptomatic Intracranial Disease (WASID) trial showed that patients with symptomatic 70% to 99% intracranial arterial stenosis are at particularly high risk of ipsilateral stroke on medical therapy: 18% at 1 year (95% CI = 3% to 24%). The Wingspan intracranial stent is another therapeutic option but there are limited data on the technical success of stenting and outcome of patients with 70% to 99% stenosis treated with a Wingspan stent. Methods: Sixteen medical centers enrolled consecutive patients treated with a Wingspan stent in this registry between November 2005 and October 2006. Data on stenting indication, severity of stenosis, technical success (stent placement across the target lesion with Results: A total of 129 patients with symptomatic 70% to 99% intracranial stenosis were enrolled. The technical success rate was 96.7%. The mean pre and post-stent stenoses were 82% and 20%. The frequency of any stroke, intracerebral hemorrhage, or death within 30 days or ipsilateral stroke beyond 30 days was 14.0% at 6 months (95% CI = 8.7% to 22.1%). The frequency of ≥50% restenosis on follow-up angiography was 13/52 (25%). Conclusion: The use of a Wingspan stent in patients with severe intracranial stenosis is relatively safe with high rate of technical success with moderately high rate of restenosis. Comparison of the event rates in high-risk patients in Warfarin-Aspirin Symptomatic Intracranial Disease (WASID) vs this registry do not rule out either that stenting could be associated with a substantial relative risk reduction (e.g., 50%) or has no advantage compared with medical therapy. A randomized trial comparing stenting with medical therapy is needed. GLOSSARY: FDA = Food and Drug Administration; HDE = Humanitarian Device Exemption; ICH = intracerebral hemorrhage; WASID = Warfarin-Aspirin Symptomatic Intracranial Disease.

Tin mining carried out on the Jos Plateau since the beginning of the last century has disturbed some 320 km2 of agricultural land. Formal attempts at reclamation of this land failed, but local farmers have developed a successful informal strategy for reclamation. This paper reports on a study undertaken to comprehend the farmers’‘informal’ approach to soil fertility management. Their soil fertility management practices centre on the use of a complex combination of traditional organic manures and ‘modern’ inorganic fertilizers that they have developed entirely on the basis of experimentation. A central focus of this paper is therefore the empirical knowledge base of the farmers and an assessment of any underlying scientific explanations for their strategies, including an analysis of their assertion that different brands of NPK fertilizers differ in their nutrient value. This discussion is followed by a consideration of the difficulties in accessing and understanding empirical knowledge. It is concluded that farmers’ knowledge and understanding of the values of different fertilizers and manures does have a scientific basis. It is argued that for further agricultural development to take place on the Jos Plateau, there must be synergy between farmers’ empirical knowledge (which has led to the development of successful and effective soil fertility management strategies, unlike the attempts of the local ‘scientific’ communities) and scientific knowledge (which can identify health and environmental hazards which may not be immediately visible to farmers).

The combination of a rising population and increased food demand has placed tremendous pressure on the land resources of Bangladesh. These pressures are exacerbated by the annual wet-season floods which frequently devastate much of the agricultural land. Successive governments have therefore sought international aid to assist in the development of flood control measures. Of particular importance are 14 major schemes which aim to provide protection from 20–25 year return floods by the construction of earth-embanked enclosures. There is no doubt that these schemes have been very successful in protecting valuable agricultural areas from floods and hence increasing agricultural production. There is, however, growing evidence from a range of sources for long-term deterioration in soil fertility within the project areas. The study reported here is the first to systematically examine the changes taking place in soil properties following the establishment of a flood control, drainage and irrigation project. Comparison of two soil series, sampled from within and without the project area, demonstrate that within six years of project establishment, significant adverse changes have occurred in several soil properties; these include increasing acidity and a decline in available nutrients. The changes are attributable to a combination of poor management strategies and the absence of the annual flood input of silt. As Bangladesh cannot afford any decline in agricultural output, it is vital to establish whether adverse changes recorded here are occurring in other projects. This can be achieved by the establishment of a nationwide programme of soil fertility monitoring. © 1998 John Wiley & Sons, Ltd.

Close agreement between the measured and predicted insertion loss between dipole antennas above a conducting ground plane has produced a calculable standard dipole antenna. Antenna factors of dipole antennas in the frequency range 30 MHz to 500 MHz have been determined to an uncertainty of /spl plusmn/0.1 dB. Though the design of the dipole is not new, the key achievements are: the use of a large standard ground plane, the use of the program NEC to obtain broadband results, careful design of antennas and supports and precision measurements. Insertion loss and antenna factor are calculated by two independent methods, numerical and analytical, and the results agree to better than /spl plusmn/0.05 dB. The NPL calculable dipole antenna was originally designed for electromagnetic compatibility (EMC) applications in the frequency range 30 MHz to 1 GHz, but it can be used wherever electric field strength of free-field signals needs to be precisely measured. The technique was applied to monopole antennas for which antenna factor was determined to an uncertainty of /spl plusmn/0.15 dB over the frequency range 10 MHz to 100 MHz. In this paper, traceability of antenna factor to the predicted value rather than a measured value is justified.

Over thirty-three years I have translated a good deal of Old English poetry into verse. Teachers of Old English sometimes feel unwanted, but the true Cinderella of English Studies is not Old English: it is translation. Although English was first written to translate the good news of Christianity to the Angles, English literary history has traditionally allowed translation only one moment of glory, with the Renaissance translators as supporters of the triumph of English, the language of a nation with its own 'authorized' Bible. Yet translation was a chief source of writing in English for a thousand years, a source which was not differentiated from what we now call original writing, and with the same prestige. Dr Johnson judged Pope's Homer 'a performance which no age or nation can pretend to equal'. He values it as a version of Homer but also as an achievement of English literature, the performance of an English author. Yet Mr Pope had already been told by the great classical scholar Richard Bentley that though his Iliad was 'a very pretty poem', he 'must not call it Homer'. What hope, then, for Alexander's Beowulfi1 Bentley 's ruling limits the role of literary translation to prettiness, though the prettiness of poetry. With the rise of a more scientific philology, the standing of translation fell further, and it was at this very time that Beowulf, which did not have the prestige of a classical text, began to be translated: by Turner into English (1805), Gruntvig into Danish verse (1820), and Thorkelin into Latin (in the first edition of Beowulf in 1815; Klaeber's verdict on the translation is 'practically useless'). For scholars, originals became absolutely better than any translation, at the same time that for poets originality became absolutely better than skill. Some scholars since have regarded translation as an evil, except when done by their students, when it is merely bad. I know a scholar who calls courses in Classical Civilization 'Mickey Mouse courses' because they deal with texts in translation. He taught a course on 'Chaucer and his European Background' which required students to buy a Chaucer and two other texts: The Consolation of Philosophy and Le Roman de la rose in modern

[1] Gravity waves (GWs) play critical roles in the global circulation and the temperature and constituent structures in the middle atmosphere. They also play significant roles in the dynamics and transport and mixing processes in the upper troposphere and lower stratosphere and can affect tropospheric weather. Despite significant advances in our understanding of GWS and their effects in different regions of the atmosphere in the past few decades, observational constraints on GW parameters including momentum flux and propagation direction are still sorely lacking. Global Positioning System (GPS) radio occultation (RO) technique provides global, all-weather, high vertical resolution temperature profiles in the stratosphere and troposphere. The unprecedentedly large number of combined temperature soundings from the Constellation Observing System for Meteorology, Ionosphere, and Climate and Challenging Minisatellite Payload GPS RO missions allows us to obtain GW perturbations by removing the gravest zonal modes using the wavelet method for each day. We extended the GW analysis method of Alexander et al. (2008) to three dimensions to estimate the complete set of GW parameters (including momentum flux and horizontal propagation direction) from the GW temperature perturbations thus derived. To demonstrate the effectiveness of the analysis, we showed global estimates of GW temperature amplitudes, vertical and horizontal wavelengths, intrinsic frequency, and vertical flux of horizontal momentum in the altitude range of 17.5–22.5 km during December 2006 to February 2007. Consistent with many previous studies, GW temperature amplitudes are a maximum in the tropics and are generally larger over land, likely reflecting convection and topography as main GW sources. GW vertical wavelengths are a minimum at equator, likely due to wave refraction, whereas GW horizontal wavelengths are generally longer in the tropics. Most of the waves captured in the analysis of the GPS data are low-intrinsic frequency inertia-GWs, and the estimated intrinsic frequencies scaled by the Coriolis parameter also show a strong maximum at equator. Enhanced wave fluxes are linked to convection, topography, and storm tracks, among others. As preliminary tests of the analysis in deriving horizontal propagation directions, we compared the GPS estimates with the corresponding estimates from the U.S. high vertical resolution radiosonde data using the conventional Stokes parameters method and we also conducted a separate analysis of the GPS data over the southern Andes in South America. We also showed the first global estimates of GW propagation directions from the GPS data. Finally, the sensitivity of the analysis to the temporal and spatial dimensions of the longitude × latitude × time cells and the uncertainties of the analysis and possible ways to reduce these uncertainties are discussed.

This paper presents a design of a compact microstrip patch antenna with the ability of controlling the number of bands and the operating frequencies independently. The antenna comprises a main patch and four sub-patches fed by a 50Ω microstrip line. It is designed to generate up to five separate modes to cover the frequency range from 900 MHz to 3 GHz for the operation of wireless devices supporting multiple standards including Global System for Mobile communication (GSM900, 880–960 MHz), Digital Communication System (DCS1800, 1710–1880 MHz), Universal Mobile Telecommunication System (UMTS, 1920–2170 MHz), Wireless Local Area Network (WLAN, 2400–2483.5 MHz) and low band Worldwide Interoperability for Microwave Access (WIMAX, 2.5 to 2.8 GHz) The design verified through both numerical simulation and measurement of an experimental prototype.

Stroke is the third leading cause of death in the USA, Canada, Europe, and Japan. According to the American Heart Association and the American Stroke Association, there are now 750 000 new strokes that occur each year, resulting in 200 000 deaths, or 1 of every 16 deaths, per year in the USA alone. Endovascular therapy for patients with acute ischemic stroke is an area of intense investigation. The American Stroke Association has given a qualified endorsement of intra-arterial thrombolysis in selected patients. Intra-arterial thrombolysis has been studied in two randomized trials and numerous case series. Although two devices have been granted FDA approval with an indication for mechanical stroke thrombectomy, none of these thrombectomy devices has demonstrated efficacy for the improvement of patient outcomes. The purpose of the present document is to define what constitutes adequate training to perform neuroendovascular procedures in patients with acute ischemic stroke and what performance standards should be adopted to assess outcomes. These guidelines have been written and approved by multiple neuroscience societies which historically have been directly involved in the medical, surgical and endovascular care of patients with acute stroke. The participating member organizations of the Neurovascular Coalition involved in the writing and endorsement of this document are the Society of NeuroInterventional Surgery, the American Academy of Neurology, the American Association of Neurological Surgeons/Congress of Neurological Surgeons Cerebrovascular Section, and the Society of Vascular & Interventional Neurology.

Testing electronic equipment for radiated emissions requires the accurate calibration of antennas. This in turn entails the use of a high-quality measurement site. The design of an open-field site for the calibration of antennas in the frequency range 30-1000 MHz is described. An antenna that is used as a primary standard must have a calculable antenna factor since there are uncertainties in quantifying the quality of the site and hence of setting up a known field. The design of a standard dipole antenna and the S-parameter characterization of its balun/matching network is described, followed by methods for calibrating the antenna factor of antennas.

The author describes how small, fully anechoic chambers can be constructed at a fraction of the cost of traditional EMC facilities, and still provide an acceptable route to full-compliance testing for most equipment.

Eighteen patients underwent stenting for symptomatic basilar artery stenosis. There were three major periprocedural complications (16.7%) without fatality. At a mean 26.7 ± 12.1-month follow-up, 15 patients (83.3%) had an excellent long-term outcome. Only one patient (5.6%) had moderate disability from recurrent stroke, and two patients died of medical illness at 30 and 36 months after stenting. In this uncontrolled study, stenting appeared to be effective in reducing stroke risk and death and worthy of further scrupulous trial.

A major source of uncertainty in electromagnetic-compatibility conformance testing is the antenna factor. Until recently, broadband antennas in the frequency range 30 MHz-1 GHz were calibrated typically to an uncertainty of ±2 dB. Antennas can now be calibrated to an uncertainty of less than ±0.5 dB. This has made it possible to quantify a second category of uncertainties which arise when the antenna is used for emission testing on an open-field site. Ideally, the most useful calibration is of free-space antenna factors, but when antennas are used above a ground plane mutual-coupling effects can alter the antenna factor. The directivity of the antenna affects the magnitude of the received signal; balun imbalance affects the received signal; and the phase centre of log-periodic antennas changes with frequency. On top of this there are site effects which include reflections from surrounding objects, reflections from antenna-support structures and input cables and edge diffraction from the ground plane. These effects can be quantified to uncertainties as low as ±0.1 dB using antennas with calculable antennas factors.

A follow-up study of a cohort of suburban alcoholics who are comprehensively served by the public mental health sector used a Cox survival time analyses to examine the relationship of patient characteristics, receipt of outpatient services and readmission to inpatient care. Patients were followed up until their first readmission to inpatient care or for 2 yr subsequent to an inpatient episode. As expected, established chronicity was associated with short "survival" in the community, as were youth and living alone. For first admissions, the receipt of aftercare was associated with a decreased likelihood of readmission, especially in conjunction with inpatient stays of treatment that included rehabilitation services. Patients who had established a pattern of chronicity, however, appeared resistant to the effect of these services. The transition from inpatient to aftercare services was identified as a crucial point in treatment. Aftercare patients who did not receive services beyond 6 months in the community were likely to be readmitted, suggesting that this period is also an important focus for treatment planning.

The article reports on decision making in an industrial environment. The author focuses on decisions related to product routings made at the Alloys Plant of Reynolds Metals Company of Sheffield, Al...