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International audience; In this paper, we introduce new correlation technologies for measuring Power-Density of mobile devices in the framework of Over The Air (OTA) testing. The correlation technologies use convolutional signal processing algorithms. Measurements obtained using minimally invasive ElectroOptical (EO) probes are compared to those from classical nearfield and far-field measurement solutions demonstrating excellent accuracy for applications at mmWave frequencies. Influence of separation distance between the Device Under Test (DUT) and the probing system (PS) on the near-field spatial correlation functions is studied. Broadband measurement results are successfully compared to full-wave 3D EM solvers in time and frequency domains. Perspectives for optically synchronized interferometric-correlation technologies are drawn for accurate measurements, in noisy environments, of stochastic EM fields using power-spectra and energy-spectra metrics.

Scattering properties of millimeter waves (mmW) remain relatively unknown compared to lower frequency bands, although their study is of interest considering the increasing number of civil applications, especially in the $W$ -band. In this communication, we present an efficient measurement setup that provides scattering measurements with spatial and polarization diversities. The targeted application is foreign object debris (FOD) detection and identification for surveillance of airport runways. Most existing systems are monostatic but rapid advances in mmW technology pushes toward the deployment of multistatic radars on either side of airport runways. In the following, we investigate the contribution of multistatic measurements with a special focus on the reconstruction of glass and brake pad debris, courtesy of DGAC (French civil aviation). We also present an efficient approach for making images of FODs. For this, we process scattered field measurements with an additive (with respect to polarization) backpropagation algorithm. First images include all measured points taken from the upper hemisphere. In order to get closer to the final application, we restrict the field of view to receivers facing the transmitter. Both approaches provide very good shape reconstruction of the glass debris and the central zone of the brake pad. To the best of our knowledge, this is the first time that full-3-D measurements have been conducted on FODs in the $W$ -band. It is also the first example of a 3-D qualitative image of FOD obtained from measured data in the $W$ -band.

International audience; We describe the design, fabrication and measurements of an axisymmetric dielectric lens, featuring a sectorial radiation pattern at 77 GHz. It will be used as the primary feed of a lens-based compact antenna test range (CATR). Due to symmetry of revolution, the sectorial lens profile can be designed in one dimension by using phase only control. The phase variation is echoed on the lens depth. The resulting stepped lens is simulated using France Telecom Orange Labs SRSRD software (¿in-house¿ software developed for dielectric axisymmetric radiating structures) and measured in an anechoic chamber at 77 GHz. Two lenses were fabricated with different materials: PVC and polyurethane, respectively. Good agreements were obtained between simulations and measurements. Less than 0.2 dB ripple in the central beam are obtained for the polyurethane lens although relatively high secondary lobes occur at 11°. Comparisons between the near field of a CATR illuminated by a small horn providing a uniform amplitude taper and the sectorial lens are conducted using numerical simulations. Results show that on-axis oscillations are reduced from 6 to 1 dB with the sectorial lens.

Objectives: To define the characteristics of optimum implantation corridors in vertebral bodies C2 to C7 and T10 to S1, using computed tomography examination. Methods: Measurements were taken from 207 vertebrae from 35 different adult dogs. Results: Implantation corridors of the cervical vertebrae are narrow. The width preserving the transverse hole is less than 2·5 mm in 68·6 per cent of the 86 vertebrae C2 to C6. Dorsal implantation corridors of the last four thoracic vertebrae are narrow, and major anatomical structures are very close to their emergence point. In 63 per cent of the 40 thoracic vertebrae, the right azygos vein is at a distance less than or equal to 1 mm from the vertebral body. The first six lumbar vertebrae have broader corridors. Furthermore, vascular structures are far from the emergence point. The last lumbar vertebra and the sacrum have a broad pedicle, which provides an alternative site for implant placement. Clinical Significance: For the vertebrae L1 to S1, the dorsal implantation can be performed. For the cervical vertebrae, the risk of laceration of the vertebral artery is high. For the last four thoracic vertebrae, the dorsal implantation should not be used.

Incoherent elastic neutron scattering experiments on members of the cholinesterase family were carried out to investigate how molecular dynamics is affected by covalent inhibitor binding and by differences in primary and quaternary structure. Tetrameric native and soman-inhibited human butyrylcholinesterase (HuBChE) as well as native dimeric Drosophila melanogaster acetylcholinesterase (DmAChE) hydrated protein powders were examined. Atomic mean-square displacements (MSDs) were found to be identical for native HuBChE and for DmAChE in the whole temperature range examined, leading to the conclusion that differences in activity and substrate specificity are not reflected by a global modification of subnanosecond molecular dynamics. MSDs of native and soman-inhibited HuBChE were identical below the thermal denaturation temperature of the native enzyme, indicating a common mean free-energy surface. Denaturation of the native enzyme is reflected by a relative increase of MSDs consistent with entropic stabilization of the unfolded state. The results suggest that the stabilization of HuBChE phosphorylated by soman is due to an increase in free energy of the unfolded state due to a decrease in entropy.

This paper presents the design of a thinned reflectarray. The phase-shifting elements are slotted rectangular microstrip antennas with via connection to the ground plane. They are disposed in a regular grid. The thinning procedure is used to determine which elements may be removed, according to the desired radiation pattern, without significant change in directivity. For this approach, a genetic algorithm is proposed. © 2005 Wiley Periodicals, Inc. Microwave Opt Technol Lett 46: 559–562, 2005; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.21050

A major result of incoherent elastic neutron-scattering experiments on protein powders is the strong dependence of the intramolecular dynamics on the sample environment. We performed a series of incoherent elastic neutron-scattering experiments on lyophilized human butyrylcholinesterase (HuBChE) powders under different conditions (solvent composition and hydration degree) in the temperature range from 20 to 285 K to elucidate the effect of the environment on the enzyme atomic mean-square displacements. Comparing D(2)O- with H(2)O-hydrated samples, we were able to investigate protein as well as hydration water molecular dynamics. HuBChE lyophilized from three distinct buffers showed completely different atomic mean-square displacements at temperatures above approximately 200 K: a salt-free sample and a sample containing Tris-HCl showed identical small-amplitude motions. A third sample, containing sodium phosphate, displayed highly reduced mean-square displacements at ambient temperature with respect to the other two samples. Below 200 K, all samples displayed similar mean-square displacements. We draw the conclusion that the reduction of intramolecular protein mean-square displacements on an Angstrom-nanosecond scale by the solvent depends not only on the presence of salt ions but also on their type.

Thirty-eight coronary care units (CCUs) in France participated in this double-blind, placebo-controlled, multicentre study to assess the efficacy of flurbiprofen, a non-steroidal anti-inflammatory agent (NSAID) with potent anti-platelet activity (FAA), in the prevention and recurrence of myocardial infarction (MI) and reocclusion of the infarct-related artery (IRA) in patients successfully treated for acute MI by thrombolysis and/or coronary angioplasty within 6 h of onset of symptoms. A coronary angiogram was performed within the first 24 h to confirm successful reperfusion. Two hundred and thirty-three patients (group 1) were randomly allocated to flurbiprofen 50 mg twice daily and 228 patients (group 2) to placebo. All patients complied with the entry criteria, and drug treatment was commenced within 48 h of MI. Patients were assessed at 3 weeks, 3 months and 6 months, data being recorded on major clinical events and survival status. Overall mortality was low (1.1%) and similar for both groups, confirming the benefit of early reperfusion therapy. The reinfarction rate documented during the 6-month follow-up was 3% (7/233) in group 1 and 10.5% (24/228) in group 2 ( P

An enquiry was carried out between December 1989 and January 1990 involving 749 cardiologists and 8,846 general practioners based throughout France to evaluate the number of myocardial infarctions diagnosed each year, to determine how the patients are transported to hospital and to assess the average delays of transportation. This enquiry showed that cardiologists diagnosed 15 cases of myocardial infarction per year: their first reflex is to visit the patient, sometimes accompanied by the emergency medical service if available at the time of the patient's call, or to advise the patient to call the emergency service straight away if it is not possible for them to visit the patient immediately. The delay of transportation is less than 30 minutes in 45% of cases and over 60 minutes in 10% of cases. Regional differences were observed and are analysed. General practitioners diagnose 4 cases of myocardial infarction per year: the principal attitude is the same as that of the cardiologists, except that the general practitioner is available to visit the patient more often and is called out more easily. The means of transport and the delays of transportation are very similar to those observed with the cardiologists. This analysis of the management of myocardial infarction in France in 1990 may help organise actions to shorten the time between the onset of chest pain and the institution of thrombolytic therapy.

Thrombolytic therapy in acute thrombotic diseases was introduced in France in the late 1960s. It has been applied in acute myocardial infarction since 1972 and was reported in 1975 [1]. The beneficial effect was appreciated in randomized studies on clinical follow-up dealing with cardiac death, rhythm disturbances and heart failure during the acute phase of myocardial infarction and on recurrent myocardial infarction, aneurysms and cardiac or noncardiac deaths in long-term follow-up [2].

Numerous data and controversies have arisen from studies concerning thrombolysis in acute myocardial infarction over the past five years. It is known that coronary artery obstruction is present in approximately 90 percent of acute infarctions during the first 4 hours of onset. Spontaneous renewed flow is noted in 30 percent of cases following the 12th hour, and in 50 percent of cases following the 3rd week. It is possible to obtain early renewed flow in 85 percent of cases with the administration of intracoronary streptokinase, and in 55 to 70 percent of cases with parenteral administration of streptokinase or urokinase. Controversy centers around the effectiveness of thrombolysis in limiting the size of the infarction, thus preserving cardiac function. Due to the numerous different protocols used and the insufficient number of cases reported in randomized studies, it is not possible to determine the superiority of one technique over another in preserving ischemic myocardium. After taking into account the technical constraints of the procedure and the contradictory published results, therapeutic fibrinolysis should remain a research modality as long as its effectiveness in preserving ischemic myocardium has not been established.

Experimental studies on rabbits have shown that CY 222, a low molecular weight heparin (mean: 2.500 daltons), has the anti-thrombosis properties of heparin but reduces the risk of haemorrhage in optimal doses of 1.000 AXa IC (Institut Choay) units/kg/day. The safety and effectiveness of CY 222 were tested in 47 patients presenting with a less than 5 days' old pulmonary embolism. The patients were divided into three groups according to dosage: group I (n = 16) received 500 AXa ICu/kg/day; group II (n = 17), 750 AX ICu/kg/day, and group III (n = 14), 1.000 AXa ICu/kg/day. The drug was administered by continuous intravenous infusion during 10 days. Its effectiveness was assessed from the Miller index calculated on conventional pulmonary angiograms on days 0, 5 and 10. On the 10th day of treatment, the percentage of revascularization was similar in all three groups (group I 65.9 +/- 9.9 p. 100; group II 71 +/- 6.8 p. 100; group III 68 +/- 8.5 p. 100), but the improvement was significantly more rapid in group III patients. Embolism recurred in 5 cases (2 in group I, 1 in group II, 2 in group III) and was fatal in 1 case (group I). Haemorrhagic complications were noted in 3 cases (group III patients). Except for thromboelastography, all coagulation tests were unmodified by CY 222. The anti Xa and the (very low) anti IIa activities of the drug were directly related to the doses administered.(ABSTRACT TRUNCATED AT 250 WORDS)

In a multicentre randomized open study conducted on two parallel groups the effectiveness of APSAC was compared with that of streptokinase (SK) in 116 cases of myocardial infarction treated during the first 2.75 hours. APSAC (30 IU) was administered by intravenous bolus injection over 2 to 5 minutes, and SK (1.5 million IU) by intravenous infusion over 60 minutes. The patency of the coronary artery responsible for myocardial infarction was evaluated by coronary arteriography performed 1.74 h on average after the beginning of treatment; it was 70 p. 100 in the APSAC group and 51 p. 100 in the SK group (p less than 0.05). The fall in plasma fibrinogen was similar in both groups (mean minimum level; 0.2 g/l). Haemorrhages occurred in 9/58 patients treated with APSAC (15.5 p. 100) and in 13/58 patients treated with SK (22.4 p. 100); these haemorrhages took place during the first 24 hours in 4 patients of the APSAC group and in 10 patients of the SK group. Five patients died: 2 in the APSAC group and 3 in the SK group. In a subgroup of 38 patients who underwent 3 control coronary arteriographies (at 90 min, 24 hours and 3 weeks), the patency rates were 63 p. 100, 82 p. 100 and 93 p. 100 respectively with APSAC and 44 p. 100, 86 p. 100 and 92 p. 100 respectively with SK (NS). No coronary reocclusion occurred in the APSAC group, as against 3 (1 early, 2 delayed) in the SK group. It is concluded that APSAC seems to be more effective than intravenous streptokinase; it is easier to administer (bolus injection) and does not carry a higher risk of haemorrhage.

Twenty six patients with acute (less than 5 days) pulmonary embolism (PE) confirmed by bilateral pulmonary angiography with a Miller index greater than 15 were given tissue plasminogen activator (Alteplase) (rt-PA) intravenously (n = 20) or directly into the pulmonary artery (n = 6). The dosage was 100 mg/7 hours (bolus 10 mg + 40 mg/2 hours + 50 mg/5 hours). Heparin (5000 IV as a bolus and 1000 IV/hour) was associated in all cases. The Miller index decreased from 24 +/- 1 (n = 26) before treatment to 12 +/- 1 (n = 25) (p less than 0.001) after 100 mg of Alteplase, and from 25 +/- 0.4 (n = 14) to 22 +/- 0.5 (n = 14) (p less than 0.001) after 50 mg. The mean pulmonary arterial pressures fell from 30 +/- 2 mmHg to 21 +/- 2 mmHg after 50 mg (n = 26) (p less than 0.001) and to 14 +/- 1 (n = 25) (p less than 0.001) after 100 mg of Alteplase. A decrease in mean pulmonary artery pressures (-22%, p less than 0.001) and total pulmonary resistances (-29%, p less than 0.001) was obtained after one hour of thrombolysis in 12 monitored patients. There were no fatalities. Severe haemorrhage occurred in 6 cases. Therefore, Alteplase induced a rapid dissolution of recent intrapulmonary thrombi without inacceptable haemorrhagic complications. Its action could be particularly beneficial in patients with right ventricular failure due to life threatening pulmonary embolism.

Many investigators have reported about beneficial results with thrombolytic therapy in patients with acute pulmonary embolism. Streptokinase and urokinase have been used for more than 15 years, but the conditions of use of these agents still remain controversial. Optimal dosage and treatment schedule are still evolving. For streptokinase most investigators adopt a fixed dosage schedule: a loading dose of 250,000 units followed by a maintenance infusion of 100,000 units per hour for 24 to 72 hours. For urokinase numerous dosage regimens have been used such as: high dosage schedule 4,400 units per kilogram per hour for twelve to 24 hours with or without loading dose; moderate dosage 1,600 to 2,000 units per kilogram per hour for 24 hours and low dosage in bolus. With these treatments there is a trend to reduced in-hospital-mortality in massive pulmonary embolism; the early pulmonary revascularization and the hemodynamic improvement are higher than those noticed with heparin. These results are obtained with a minimum of complication essentially bleeding in 10 or 15%; most bleeding being located at puncture site. More recently, new thrombolytic agents have been used in acute pulmonary embolism. Only four studies have tested rt-PA which is effective and relatively safe, but the optimal dose regimens remain to be determined. Less information is available concerning Anisoylated Plasminogen Streptokinase Activator Complex (APSAC), the angiographic improvement seems to be rapid and important (50% on average) but the decrease of fibrinogen is important too and comparable with streptokinase. Considering the good results of thrombolytic treatment of acute submassive and massive pulmonary embolism, there is a doubt as to whether the pulmonary embolectomy has any place in the pulmonary embolism patients except in those with cardiac arrest. In the near future new thrombolytic drugs could be more efficient on pulmonary embolism and deep venous thrombosis, and thus the bleeding risk might be decreased.

[This corrects the article DOI: 10.1016/j.mtbio.2024.101117.]., (© 2024 The Author(s).)