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Notes: Magnetron plasmas are of great current interest for semiconductor manufacturing applications because of their high ion density and low operating pressure. We have studied the properties of a magnetron ion etching system using CF4 and CF4/O2 with respect to the plasma chemistry and the interaction of the plasma with both the etched substrate and the chamber walls. The higher dissociation and ionization rates lead to significant changes in the species present in the plasma as compared to a conventional reactive ion etching (RIE) plasma. The F atom concentration in a CF4 magnetron plasma is much higher than in a RIE plasma. The addition of O2 leads to only a small further enhancement and produces a decrease in the Si etch rate. The highly dissociated species in the magnetron plasma produce less C-F polymer, both on the wafer and on the chamber walls, relative to RIE. Sputtering of Al from the electrode produces a substantial deposit of AlFx on the chamber walls, but not on the wafer.

Notes: The effect of lignocaine pretreatment on the intra-ocular pressure response to suxamethonium and tracheal intubation was studied in 80 adult patients, divided randomly into four groups of 20 each. These groups received respectively normal saline (10 ml), lignocaine 1 mg/kg, 1.5 mg/kg and 2 mg/kg as pretreatment, in a double blind manner, one minute before anaesthetic induction with thiopentone and suxamethonium 1.5 mg/kg. Lignocaine pretreatment caused a signijicant decrease in intra-ocular pressure. Suxamethonium caused a significant increase, but lignocaine pretreatment in doses of 1.5 mg/kg and 2 mg/kg effectively kept the postsuxamethonium pressure below control values. Tracheal intubation further aggravated the postsuxamethonium increase in intra-ocular pressure. Lignocaine, in doses of 1.5 mg/g and 2 mg/kg also effectively kept the postintubation pressure values below control levels. Lignocaine, in dose of 1 mg/kg, only partially attenuated the postsuxamethonium and postintubation increase in intra-ocular pressure. In conclusion, lignocaine pretreatment, in a dose of 1.5 mg/kg, offers protection against suxamethonium- and tracheal-intubation initiated increases in intra-ocular pressure, without causing any signijicant decrease in arterial pressure.

Notes: The full C-terminal half of HK-I cDNA was cloned from common carp Cyprinus carpio. This HK-I cDNA is homologous to mammalian HK-I, in its sequence and tissue distribution and probably derives from duplication and fusion of an ancestral gene.

Notes: Patterns of oxygen consumption, ammonia and urea excretion were monitored during late embryogenesis, i.e. 5 days before mass hatching and 12 days during the free-swimming stage of whitefish larvae, Coregonus lavaretus. Oxygen consumption increased from 1.31 to 2.53 mgO2 h−1× 103 eggs−1 at hatching. Fasted, free-swimming larvae showed increasing oxygen consumption to the tenth day after hatching when it reached 5.52 mgO2h−1× 103 larvae−1. Ammonia and urea excretion increased during pre-hatching period from 52.1 to 163.2 and 26.8 to 51.4 μgh−1× 103 eggs−1, respectively. The nitrogen excretion rate increased between the sixth and tenth day of fasting, i.e. for ammonia from 117.7 to 160.9 and for urea from 35.8 to 52.5 μg h−1× 103 larvae−1. Cumulative data on nitrogen and energy metabolism indicated that during late embryogenesis, and up to the fifth day after hatching, protein dominated in the energy expenditure. During the free swimming stage, the ratio of fat to protein in energy expenditure rose from 0.86 to 1.99. Combined data for several fish species indicated high dependance of oxygen uptake during the hatching period on egg size and temperature.

Notes: Glucokinase (GK) catalyses the first step of hepatic glycolysis to store the excess dietary glucose. After rainbow trout Oncorhynchus mykiss were fed a single meal with dietary glucose and fructose, there was induction of GK expression, although no specific effect of dietary fructose was observed. This suggested that dietary fructose is not essential to improve dietary glucose Utilization.

Notes: The distributions of the diameters of skeletal muscle fibres and adipocytes were studied in rainbow trout. The cellularity of perivisceral adipose tissues and subcutaneous ventral and dorsal adipose tissues were characterized more specifically. In these tissues, a population of small adipocytes was distinguishable from larger adipocytes. The same was observed in white muscle. The effects of extrinsic factors (dietary lipid in two different thermal conditions) and intrinsic factors (strains in two different saline conditions, growth hormone) on the long-term response of the cellularity of both muscle and adipose tissues were studied. The effects of thermal environment were tested on fish fed the same ration and the effects of saline environment on fish fed ad libitum. The mean size of white muscle fibres was relatively unaffected by the different treatments tested: genetic origin and dietary lipid in different environmental conditions. There were significant differences in growth rate due to genetic origin and saline environment. The possible involvement of hyperplasia in response to these different factors is discussed. Growth hormone supplementation enhanced the percentage of small diameter fibres indicating a role of this hormone in the control of muscle hyperplastic growth. The mean size of adipose cells was affected only slightly by the different treatments tested. An increase in adipose cell size with aging and lipid content was observed. The percentage of small adipocytes also increased with aging. Thus, it is proposed that the development of adipose tissues, and thus fat retention, both result from the recruitment of new adipocytes and from the increase in size of existing adipocytes. The hyperplastic process contributed significantly to the differences in fat retention due to different treatments tested (strains, thermal and saline environments). When partially substituting fish oils for corn oils in the diet, a large increase in the ventral adipose cell size was seen indicating a potential negative effect of n-6 fatty acids on cell proliferation. Growth hormone treatment, on the contrary, induced a decrease in the size of perivisceral adipocytes. Thus, diet and hormonal status affect adipose cells size through two different metabolic pathways: lipogenesis and lipolysis respectively.

Notes: A postprandial increase in ammonia nitrogen excretion and oxygen consumption rates was observed in juvenile pike fed a natural diet or an artificial dry diet. Specific growth rate of natural diet fed pike (2.4%) was lower than that of pike fed the artificial diet (3.1%). Fifty per cent of ingesta was evacuated within 5–6 h in pike of 25 mg body weight and 9–10 h in those weighing 150mg. Daily nitrogen excretion rates were related to body weight. Respiratory quotient and energy retention efficiency were affected by the nature of the diet ingested by pike. Parameters of the energy balance (losses, retention, increment due to feeding) were related to energy intake.