Background Among asymptomatic patients with severe carotid artery stenosis but no recent stroke or transient cerebral ischaemia, either carotid artery stenting (CAS) or carotid endarterectomy (CEA) can restore patency and reduce long-term stroke risks. However, from recent national registry data, each option causes about 1% procedural risk of disabling stroke or death. Comparison of their long-term protective effects requires large-scale randomised evidence.Methods ACST-2 is an international multicentre randomised trial of CAS versus CEA among asymptomatic patients with severe stenosis thought to require intervention, interpreted with all other relevant trials. Patients were eligible if they had severe unilateral or bilateral carotid artery stenosis and both doctor and patient agreed that a carotid procedure should be undertaken, but they were substantially uncertain which one to choose. Patients were randomly allocated to CAS or CEA and followed up at 1 month and then annually, for a mean 5 years. Procedural events were those within 30 days of the intervention. Intention-to-treat analyses are provided. Analyses including procedural hazards use tabular methods. Analyses and meta-analyses of non-procedural strokes use Kaplan-Meier and log-rank methods. The trial is registered with the ISRCTN registry, ISRCTN21144362.

Corn (Zea mays L.) was planted in a Maury silt loam soil under conventional tillage and in a chemically‐killed bluegrass (Poa pratensis L.) sod in 1970 and 1971 in order to determine the behavior of nitrate and the yield of corn under both cultural systems. Nitrate under both cultural treatments was sampled before and after June rainfall periods in both years. A large fraction of the nitrate was lost from the top 90 cm of soil under the killed‐sod plots, whereas, no nitrate was lost from the conventionally‐tilled plots. The loss of nitrate under the killed sod was attributed to two factors: 1) lower evaporation from the mulched soil; and 2) deep penetration of water and nitrate through larger pores in the wetter, mulched soil. Corn yields where nitrogen was applied tended to be higher on the killed‐sod plots in a dry year (1970) and about the same in a wet year (1971). However, the no nitrogen treatment on the mulched plots had a much lower yield than did the conventionally‐tilled no nitrogen treatment in the wet year of 1971. The results suggest that higher nitrogen rates may be required when corn is grown in a killed sod mulch as compared to conventionally‐tilled corn.

Time and rates of N application to corn (Zea mays L.) grown in wet alluvial soils in western Kentucky were studied in the years 1968 through 1972. Two soils representative of the wetter soils in the area were used, Stendal silt loam and Melvin silt loam. The objective of the study was to determine the N fertilization practices that would produce highest corn yields on such soils. The early experiments were concerned with Fall vs. Spring application of N as practiced in the Midwest, but Fall‐applied N at lower rates (90 or 112 kg/ha) gave no better yields than the check treatments and even at relatively high N rates (180 and 224 kg/ha) gave such a poor response that this was changed to a comparison between Spring and Summer side‐dress applications for the last 2 years. Side‐dress application of N was nearly as good as or better than N applied at planting at both locations, although increasing the N rate at planting tended to obscure this effect. The results show that Summer side‐dressing of N on corn grown in wet soils is an effective way of fertilizing corn. They also suggest that late N application on corn made severely N deficient by excessive rain is an excellent practice.

Synopsis Species showed a differential response to lime and phosphorus rates on an acid subsoil material. There was a tendency for lime and phosphate to compensate for each other to some degree. The yield increase due to lime was apparent up to the point at which the exchangeable aluminum was immobilized.

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