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ABSTRACTObjective:To assess the reliability of dosing through two budesonide multidose dry powder inhalers (DPI) as derived from the in-vitrovariability of the fine particle dose (FPD) and the in-vivovariability of the lung deposition at different flow rates.Methods:The same two DPIs [device N (Novolizer*) and device T (Turbuhaler†)] were compared in both studies. In the in-vitrostudy, the variability of the FPD, measured at flow rates of 30–100 L/min, was determined for equal flow rates and at comparable maximal inspiratory pressures (MIP). *Novolizer, VIATRIS Group, Bad Homburg, Germany†Turbuhaler, AstraZeneca GmbH, Wedel, GermanyIn the in-vivostudy in healthy subjects (scintigraphic, randomised, crossover design) the variability of the lung deposition was determined at targeted flow rates of 45, 60 and 90 L/min for device N, and at 60 L/min for device T.Results:The variability of the FPD was lower with device N than with device T by 34%–86%. The differences were statistically significant for flow rates of 60, 70, 90 and 100 L/min (not significant for 40, 50 and 80 L/min) in the in-vitrostudy. Results for comparable MIPs showed analogous differences (79%, p= 0.004, at the clinically relevant MIP of 4.5 kPa). The variability of the lung deposition was clearly lower with the device N than with the device T. The difference was statistically significant ( p =0.029) at a comparable targeted flow rate of 60 L/min.Conclusions:Thus, this study showed that device N is likely to improve the reliability of inhalation therapy by reducing both the variability of the delivered drug and that of the lung deposition. The reliability of inhalation therapy and consequently the quality of long-term control of asthma and the patient's compliance might improve when choosing the DPI with the better characteristics.

The partial oxidation of methane to synthesis gas over Ni/α‐Al2O3catalysts (1 and 5 wt.‐% Ni loading, 71–160 and 250–355 μm particle diameter) was investigated in different types of fluidized‐bed reactors, i.e., the bubbling fluidized bed (FlB), the spout fluid bed (SFB) and the internally circulating fluidized bed (ICFB). A methane‐to‐oxygen ratio of 2:1 was used in all experiments and the temperature was varied between 700 and 800 °C. Gas velocities and catalyst masses were adjusted to assure a stable and controllable reactor operation. A nearly isothermal operation was established in all reactors. The thermodynamic equilibrium values were achieved in the FlB and SFB reactor whereas in the ICFB reactor slightly lower conversions and selectivities were obtained. Taking the direct scale‐up concept of the ICFB reactor into account, significant higher space‐time yields were obtained in this reactor than in the industrial‐scale bubbling fluidized‐bed reactor. No increase of the space‐time yield in comparison to the FlB was obtained in the SFB reactor.

Background Stroke occurs in 1% to 7% of heart surgery. Aortic arch atherosclerosis is a risk factor for intraoperative stroke, and endarterectomy has been proposed to prevent stroke during heart surgery in patients with arch atheromas. Methods and Results Intraoperative transesophageal echocardiography was performed in 3404 patients undergoing heart surgery between 1990 and 1996. Use of transesophageal echocardiography was unselected and based on equipment availability. Aortic arch atheromas (>=5 mm, or mobile) were seen in 268 (8%) patients. They were evaluated for intraoperative stroke (confirmed by a neurologist and cerebral infarction on computed tomography or magnetic resonance imaging). Arch endarterectomy was performed in 43 patients as an adjunct to their cardiac procedure in an attempt to prevent intraoperative stroke. The intraoperative stroke rate in all 268 patients with atheromas was high (15.3%). On univariate analysis, age, previous stroke, and arch endarterectomy were significantly associated with intraoperative stroke. On multivariate analysis, age (odds ratio 3.9, P = .01) and arch endarterectomy (odds ratio 3.6, P = .001) were independently predictive of intraoperative stroke. Mortality rate in all 268 patients was high (14.9%). These patients with atheromas also had a long recovery room, intensive care unit, and total hospital length of stay (48 days). Conclusions Patients with protruding aortic arch atheromas are at high risk for intraoperative stroke, significant and multiple morbidity, prolonged hospital stay, and death resulting from heart surgery. Aortic arch endarterectomy is strongly associated with intraoperative stroke; its use should be carefully considered in light of these results. (Am Heart J 1999;138:746-52.)

An internally circulating fluidized-bed (ICFB) reactor (i.d.eff = 1.9 cm, Hriser = 10 and 20 cm, respectively) was applied to investigate the catalytic partial oxidation of methane to synthesis gas over Ni/α-Al2O3 (Ni loading, 1 and 5 wt %; particle diameter, 71−160 and 250−355 μm). The experiments were performed at 800 °C by applying a methane to oxygen ratio of 2:1. The contact times in the draft tube (≪ 0.1 g·s·mL^-1) were sufficient to obtain nearly thermodynamic equilibrium values for the methane conversion (XCH4,eq = 92%) and selectivities to hydrogen (SH2,eq = 97%) and carbon dioxide (SCO,eq = 97%). The achieved results indicate the general suitability of an ICFB reactor for the partial oxidation of methane to synthesis gas. However, stable and controllable reactor operation with sufficient solids circulation through the draft tube was possible only over a narrow range of gas velocities (0.75−1.50 m·s^-1). Furthermore, the conversion and selectivities were strongly influenced by the temperature distribution in the ICFB reactor. Especially, the decrease of temperature in the top of the draft tube and in the fountain region promoted backreactions reducing the conversion of methane. Furthermore, catalyst deactivation due to carbon depositions occurred in the ICFB reactor. This effect caused for the 1 wt % Ni catalyst a significant drop of the activity during 150 h of time on stream. The methane conversion decreased in the range of 12% for a catalyst particle fraction of 71−160 μm. It was shown by TEM that two different types of carbon (encapsulating and whisker carbon) were deposited on the surface. The first species resulted in a reversible deactivation (activation of the catalyst by carbon dioxide in the reverse Boudouard reaction was partially possible), whereas the second species resulted in an irreversible deactivation due to a Ni loss by removing the carbon fibers which had Ni sites on top of the filament.

The oxidative coupling of methane to C2‐hydrocarbons (OCM) over a La2O3/CaO catalyst (27 at.%) was investigated in an internally circulating fluidized‐bed (ICFB) reactor (IDeff= 1.9 cm, Hriser= 20.5 cm). The experiments were performed in the following range of conditions: T= 800−900°C, pCH4:pO2pN2= 57.1–64:16–22.9:20 kPa. The obtained C2selectivities and C2yields were compared with the corresponding data from a spouted‐fluid‐bed reactor (ID= 5 cm) and a bubbling fluidized‐bed (FIB) reactor (ID= 5 cm). The maximum C2yield in the internally circulating fluidized‐bed (ICFB) reactor amounted to 12.2% (T= 860°C, 38.7% C2selectivity, 31.5% methane conversion), whereas in the FIB reactor a maximum C2yield of 13.8% (T= 840°C, 40.4% C2selectivity, 34.2% methane conversion) was obtained. The lowest C2yield was achieved in the spouted‐bed (SFB) reactor (Yc2= 11.6%, T= 840°C, 36.2% C2selectivity, 32.0% methane conversion). The highest space‐time yield of 24.0 mol/kgcat.h was obtained in the ICFB reactor, whereas in a FIB reactor only a space‐time yield of 9.6 mol/kgcatcould be obtained. The performance of the ICFB reactor was strongly influenced by gas‐phase reactions. Furthermore, stable reactor operation was possible only over a narrow range of gas velocities.

IN 1963 Huger1,2discovered and described a new type of insect virus Rhabdionvirus oryctes Huger in populations of the rhinoceros beetle Oryctes rhinoceros L. (Dynastinae, Scarab., Col.) in Malaya. This pathogen is at present being tested for its use in the biological control of the rhinoceros beetle, which has become a devastating pest of coconut palm trees since its recent introduction to the islands of the South Pacific3–5. The first attempts to introduce Rhabdionvirus into populations of Oryctes began in 1967 in Western Samoa, where no virus disease had been found during the five years of investigation of the beetle population6. Grubs infected with the virus were supplied by the laboratory of the Biologische Bundesanstalt (Institut für Biologische Schädlingsbekämpfung) in Darmstadt, Germany.