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We present magnetization data on three polycrystalline specimens of Sm 0.97 Gd 0.03 Al 2 : (1) as-cast (grainy texture), (2) powder, and (3) re-melted fast-quenched (plate). The data are presented for nominally zero- (ZFC) and high-field-cooling (HFC) histories. A zero cross-over in magnetization curve at some temperature T = T 0 was seen in ZFC data on grainy and powder samples, but not in the plate sample. At fields surpassing magnetocrystalline anisotropy, a 4f magnetic moment flip was still evidenced by HFC data in all samples at a compensation temperature T comp , which must necessarily be treated as distinct from T 0 ( T 0 may not even exist). Proper understanding of T comp should take account of thermomagnetic history effects.

The results of dc and ac magnetization, electrical resistance, and heat-capacity studies in an admixed rare-earth alloy ${\text{Nd}}_{0.75}{\text{Gd}}_{0.25}{\text{Rh}}_{3}{\text{B}}_{2}$, which is close to the zero magnetization limit, are reported. Interesting observations include the two antiferromagneticlike transitions, concomitant repeated/multiple magnetic compensation behavior, and a characteristic oscillatory magnetic response, with temperature dependence of magnetization at low fields crossing the $M=0$ axis thrice. The effective coercive field relating to the residual remanence also has an oscillatory response, with two minima located close to two ``zero-cross over'' temperatures. The unusual behavior in ${\text{Nd}}_{0.75}{\text{Gd}}_{0.25}{\text{Rh}}_{3}{\text{B}}_{2}$ is conjectured to arise from its anisotropic hexagonal structure, with planar anisotropy, resulting in a quasi-one-dimensional electronic structure and the accentuated role of conduction-electron polarization near the zero magnetization limit.

Rare earth based intermetallics, SmScGe and NdScGe, are shown to exhibit near zero net magnetization with substitutions of 6 to 9 atomic percent of Nd and 25 atomic percent of Gd, respectively. The notion of magnetic compensation in them is also elucidated by the crossover of zero magnetization axis at low magnetic fields (less than 103 Oe) and field-induced reversal in the orientation of the magnetic moments of the dissimilar rare earth ions at higher magnetic fields. These magnetically ordered materials with no net magnetization and appreciable conduction electron polarization display an attribute of an exchange bias field, which can be tuned. The attractively high magnetic ordering temperatures of about 270 K, underscore the importance of these materials for potential applications in spintronics., Comment: 6 page text + 5 figures

The Sm intermetallic compound SmScSi, a ferromagnet with an unusually high Tc of 270 K, has been driven into a “zero magnetization” state by substituting 9 at.% of Sm by Nd. The magnetic characteristics have been studied by dc magnetization, ac susceptibility and specific heat measurements and comparisons are made with the Gd doped SmAl2 systems.

Eighty five very low birth weight (VLBW) babies with birthweight less than 1250 g were randomly assigned such that 43 received parenteral nutrition (PN) with amino acid based glucose electrolyte solution (Vamin) and lipid emulsion (Intralipid) in the first 16 days of life. The other 42 (control group) received conventional intravenous dextrose with or without electrolytes plus enteral milk regimen. Baseline clinical parameters and neonatal problems encountered in the two groups were similar. There was no significant difference in the mortality rate in the two groups (48.9% in PN group and 42.9% in control group: X2 = 0.3, p0.05). The commonest cause of mortality in both the groups was septicemia (16.3% and 26.1% in PN and control groups, respectively). Local complications, sepsis and fluid electrolyte disturbances were similar in the two groups. Azotemia (25.6%), hyperlipidemia (9.3%), metabolic acidosis (9.3%) and prolonged cholestasis (14%) were commoner in the PN group but were reversible with early recognition. Time taken to regain birthweight was also similar in the two groups (X2 = 14.2 and 15.2 days for PN and control groups, respectively). Thus, PN failed to improve the survival or early weight gain in the routine management of the VLBW babies in our unit.

Two hundred and forty seven low birthweight (LBW) survivors of our Neonatal Intensive Care Unit and 164 normal birthweight controls were followed up longitudinally from birth to 4 years and their growth trends (weight, height, head circumference) were expressed as mean Z scores in 500 g birthweight categories. Whereas LBW's demonstrated rapid growth in the first 6 months of life, followed by generally parallel trends with some tendency to rise, controls showed distinct growth faltering especially after one year. Only 30.8% of LBWs (and 49% of controls) were within the designated catch up levels for weight by age 4 years. The corresponding number for catch up of height and head circumference in LBW's was 22.8% and 26.5%, respectively. On multiple regression analysis, the most important determinants of catch up (at 4 years) in LBW's were weight at 1 year (beta = 0.51), height at 1 year (beta = 0.31) and mother's weight (beta = 0.04). Thus, Z scores enabled the demonstration of changing growth trends, simultaneous comparisons with local controls and international standards and comparison within indices. Growth charts incorporating Z score should be made available in a simplified manner for use in the community.

Two kinds of oils (i) Polyunsaturated fatty acids (PUFA) rich Safflower oil, and (ii) Medium chain triglyceride (MCT) rich Coconut oil were added to the feeds of 46 very low birthweight (VLBW) babies to see if such a supplementation is capable of enhancing their weight gain. Twenty two well matched babies who received no fortification served as controls. The oil fortification raised the energy density of the feeds from approximately 67 kcal/dl to 79 kcal/dl. Feed volumes were restricted to a maximum of 200 ml/kg/day. The mean weight gain was highest and significantly higher than the controls in the Coconut oil group (19.47 +/- 8.67 g/day or 13.91 g/day). Increase in the triceps skinfold thickness and serum triglycerides were also correspondingly higher in this group. The lead in the weight gain in this group continued in the follow up period (corrected age 3 months). As against this, higher weight gain in Safflower oil group (13.26 +/- 6.58 g/day) as compared to the controls (11.59 +/- 5.33 g/day), failed to reach statistically significant proportions, probably because of increased statistically significant proportions, probably because of increased steatorrhea (stool fat 4+ in 50% of the samples tested). The differences in the two oil groups are presumably because of better absorption of MCT rich coconut oil. However, individual variations in weight gain amongst the babies were wide so that some control babies had higher growth rates than oil fortified ones. The technique of oil fortification is fraught with dangers of intolerance, contamination and aspiration. Long term effects of such supplementation are largely unknown.(ABSTRACT TRUNCATED AT 250 WORDS)During a period of 12 months, polyunsaturated fatty acids (PUFA) rich safflower oil and medium chain triglyceride (MCI) rich coconut oil were added to the feeds of 46 very low birth weight (VLBW) babies (birth weight of 1250-1500 g) to see if such a supplementation could augment their weight gain. In the safflower oil fortification group, 22 babies completed the study, and in the coconut oil fortification group, 24 did. 22 babies who received no fortification served as controls. The oil fortification raised the energy density of the feeds from approximately 67 kcal/dl to 79 kcal.dl. Feed volumes were restricted to a maximum of 200 ml/kg/day. 3 babies of the safflower oil group and 2 each of the 2 other groups developed loose motions, but they all survived and completed the study. The diarrhea in the safflower oil group was related to addition of oil exceeding 0.5 ml and responded to discontinuation of oil. An increase in serum triglyceride values was seen in all 3 study groups, but the increase in the coconut oil group was significantly greater than the increase in the controls (p 0.05). The mean weight gain per day, weight gain per kg per day (19.47 +or- 8.67 g/day or 13.91 g/day), and mean weekly increment in skinfold thickness were significantly greater in the coconut oil group as compared to controls (p 0.05). The lead in the weight gain in this group continued in the follow-up period (corrected age, 3 months). Higher weight gain in the safflower oil group (13.26 +or- 6.58 g/day) as compared to the controls (11.59 +or- 5.33 g/day) failed to reach statistical significance, probably because of increased steatorrhea (stool fat 4+ in 50% of the samples tested). The differences in the 2 oil groups presumably occurred because of better absorption of MCI rich coconut oil. The technique of oil fortification is fraught with dangers because of aspiration and contamination. Accordingly, such fortification should be used in selected situations only, rather than as a routine nursery policy.

A comparison of total parenteral nutrition (TPN) related complication in newborns was made between two study periods, namely, 1986 (Study A) and 1989-90 (Study B). A significant reduction was seen in all complications in Study B. Local complications (thrombophlebitis, gangrene, abscess) reduced from 80.0 to 29.4%, septicemia from 52.0 to 11.7% and metabolic complications from a computed mean of 1.6 episode per baby to 0.88 episode per baby. The reduction in these complications has been attributed to the following additional inputs in the recent study (i) Additional staff (research officers, nurses, biochemist); (ii) Better training of resident staff; (iii) Use of a laminar flow system for mixing solutions; (iv) Specially designed locally manufactured intravenous sets and accessories; and (v) Use of well balanced nutrient solutions. Outstanding problems perceived are--high incidence of TPN-related cholestasis (14.7%), azotemia (26.4%), central catheter-related sepsis (75.0%) and the falling, but yet high cost of the technique (Rs. 650 per day).