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Complexation of an anionic dye 1,8 naphthalimide with cucurbit[8]uril, normally prohibited, as pre-encapsulated form in cationic surfactant and the synergic effects on the optical properties have been discussed in this paper. 1,8 naphthalimide in cationic surfactant undergoes dimerization before forming complex with cucurbit[8]uril both as 1:1 and 2:1, depending upon concentration of host. Interestingly, the monoexponential probe decay in surfactant changes to bi-exponential, when complexed with cucurbit[8]uril, of which one component has been assigned to double confined formation with surfactant and cucurbit[8] and another is due to free 1,8 naphthalimide. Increased anisotropy decay indicates rigidity around the probe, when complexed with cucurbit[8]uril.

A model based on the Finite Difference Method (FDM) is proposed for simulation of Partial Discharge (PD) Patterns in which four parameters are considered, viz. the critical field intensity for partial discharge occurrence E c , residual field intensity E r , critical field intensity for discharge propagation along the void surface (E s ) and size of the void. Though different models on PD have been developed by the researchers with various assumptions, this model is proposed assuming that the probability of Partial Discharge occurrence after each polarity inversion (zero-crossing) of the voltage waveform to be less in comparison with that near the peak of the voltage wave along with the consideration that the temperature of the void surface gets changed with the aging of the insulator. This work attempts to show the effect of both E s and size of the void on Partial Discharge as the discharge quantity at any instant is not only a function of E c , E r but also depends upon E s and void size. In this paper...

The effects of gestational age (GA) and plasma protein concentrations on the plasma protein binding of fentanyl and alfentanil were studied in preterm and term neonates. Binding experiments were performed using split-cell equilibrium dialysis. Fentanyl and alfentanil concentrations were measured using specific radioimmunoassay, and the proteins albumin and alpha-1-acid glycoprotein (AAG) were measured using radial immunodiffusion assays. In the preterm neonates, 77% of fentanyl and 65% of alfentanil was bound. In the term neonates, 70% of fentanyl and 79% of alfentanil was bound. The binding ratio of alfentanil showed a positive correlation with gestational age and AAG concentration. The binding ratio of fentanyl showed a weak, negative correlation with gestational age. These data indicate that fentanyl and alfentanil are not interchangeable at the GA studied because of age-related changes in protein binding.

Use of Debye Model to analyze insulation response, recorded from high voltage power equipments, is common among researchers. Available literature shows that relaxation characteristics of dipoles present in oil and paper have different relaxation times. This implies oil and paper condition influence separate branches in Debye Model. In the present work a new aging sensitive performance parameter is introduced. The parameter can be evaluated from Transfer Function, TF D (S) of Debye Model. The performance parameter mentioned above is one of the zeros (Z 1 ) of TF D (s).T he capability of Z 1 as an insulation condition sensitive parameter is tested on samples constructed in the laboratory.

Summary Disease states, including end-stage kidney or liver failure, can alter the protein binding of various drugs in children. The plasma protein binding of alfentanil was evaluated in blood samples from 15 children about to undergo kidney transplantation, 21 children undergoing liver transplantation, and 28 otherwise healthy children undergoing elective surgery. Compared with the healthy children, patients with kidney disease had a significant decrease in protein binding (89.2%± 5.4 v. 93.1%± 3.2), an increase in α1-acid glycoprotein concentration (108.8 mg·dl−1± 44.3 v. 71.8 mg·dl−1± 30.7), and no change in albumin concentration (3910 mg·dl−1± 754 v. 4555 mg·dl−1± 524); whereas patients with liver disease had a significant decrease in protein binding (85.9%± 6.2 v. 93.1%± 3.2), no change in α1-acid glycoprotein concentration (65.8 mg·dl−1± 31.8 v. 71.8 mg·dl ± 30.7), and a decrease in albumin concentration (3045 mg·dl−1± 1255 v. 4555 mg·dl−1± 524). Because alfentanil is highly protein bound, even small changes in the drug's free fraction could have marked pharmacodynamic effects in patients with kidney or liver failure.

Induction motors are most popularly used in modern day industrial drives. Under operating stresses and ageing, both stator and rotor of an induction motor undergoes degradation. It is necessary to properly assess the condition of motors on operation for reliable performance. Popularly employed technique for motor condition monitoring is the motor current signature analysis (MCSA) that deals with frequency response of the stator current. The stator current frequency response, along with motor internal conditions, is affected by supply conditions as well. The aim of this paper is to study effects of stator supply voltage variations on motor frequency response. Experimental and simulation study results are reported in this paper.

A male patient of 10-year-old presented with fever, headache and vomiting for last few days. He was being treated with antimalarial drugs. On 14th day of illness he again showed rise of temperature. His blood culture showed growth of Salmonella typhi. He was treated with ceftriaxone and responded favourably. Here uncomplicated falciparum malaria developed a secondary infection with salmonella during hospital stay. This uncommon association was noted rather than a mere coincidence, which rarely reported in literature.

For simulation of partial discharge (PD) patterns, a finite difference method (FDM) based model is put forward, in which two parameters are considered, viz. the critical field intensity for partial discharge occurrence E/sub c/ and residual field intensity E/sub r/. In this present simulation model both partial discharge inception and extinction are taken to be stochastic in nature. The void taken in this simulation is a narrow one for which the discharge area is taken to be fixed and is equal to the area of the top or bottom surface of the void. In this paper plane-plane electrode system is considered and the PD simulations are carried out by varying E/sub c/, considering stochastic as well as non-stochastic occurrence of partial discharge and residual field. The inception and extinction of PD, shape of PD patterns in the form of pulse amplitude and the amount of charge, which is released during PD for different cases, are studied and reported in this paper.

In practice the shape of the electrodes and the spacers in high voltage equipments are so designed that the electric stress on the electrodes, mainly on the live electrode, and on the spacers are well within the limits. This necessitates that the practical contours of the insulators have complex geometries. The complexities are often increased by the constraints imposed by the mechanical considerations in the Gas Insulated Systems (GIS). Suitable techniques are required for accurate yet efficient simulation of such complex geometries. This paper highlights a modified algorithm for computation of electric field distribution by indirect boundary element method (indirect BEM) around a complex electrode-spacer configuration used in practise in high voltage system arrangements.

There have been significant changes in the management of neonates and infants undergoing cardiac surgery in the past decade. We have evaluated in this prospective, randomized, double-blinded study the effect of large-dose fentanyl anesthesia, with or without midazolam, on stress responses and outcome. Forty-five patients6 mo of age received bolus fentanyl (Group 1), fentanyl by continuous infusion (Group 2), or fentanyl-midazolam infusion (Group 3). Epinephrine, norepinephrine, cortisol, adrenocortical hormone, glucose, and lactate were measured after the induction (T1), after sternotomy (T2), 15 min after initiating cardiopulmonary bypass (T3), at the end of surgery (T4), and after 24 h in the intensive care unit (T5). Plasma fentanyl concentrations were obtained at all time points except at T5. Within each group epinephrine, norepinephrine, cortisol, glucose and lactate levels were significantly larger at T4 (P values0.01), but there were no differences among groups. Within groups, fentanyl levels were significantly larger in Groups 2 and 3 (P0.001) at T4, and among groups, the fentanyl level was larger only at T2 in Group 1 compared with Groups 2 and 3 (P0.006). There were no deaths or postoperative complications, and no significant differences in duration of mechanical ventilation or intensive care unit or hospital stay. Fentanyl dosing strategies, with or without midazolam, do not prevent a hormonal or metabolic stress response in infants undergoing cardiac surgery.We demonstrated a significant endocrine stress response in infants with well compensated congenital cardiac disease undergoing cardiac surgery, but without adverse postoperative outcome. The use of large-dose fentanyl, with or without midazolam, with the intention of providing "stress free" anesthesia, does not appear to be an important determinant of early postoperative outcome.

The high reliability and compactness achieved by compressed gas insulation in HVAC systems, has led to the development of HVDC Gas Insulated Substations (GIS). As in case of HVAC GIS, the basic insulation components of HVDC GIS are SF6 gas and solid spacers. In this respect, it has been recognized that the breakdown strength of GIS is mainly influenced by spacers. For HVAC GIS, the problems related to spacers can be eliminated to a great extent by a careful electric stress control design1-3. However, for HVDC GIS stress control designs based on dielectric interfaces with no trapped charges are not valid, since charges get accumulated on spacer surfaces which distort the designed Laplacian field distribution. In this context, it is also kept in mind that SF6 insulation is very sensitive to local enhancement of electric field. According to this surface charge accumulation and its effects in HVDC GIS have been studied in various aspects by several researchers4-11. In order to improve the dielectric performance of epoxy spacers by properly shaping the gas-dielectric interfaces, studies on electric field optimization along the profile of the gas-dielectric interface in gas insulated systems have been reported in literature12,13. For HVDC GIS, investigations on the effects of spacer shapes on flashover characteristics have also been carried out14. Since, in contrary to HVAC GIS, the electric field distribution at steady-state in HVDC GIS is mainly controlled by the conductivity k, of the dielectric media, studies on the influence of volume and surface resistivities on the electric field distribution around GIS spacers have been done15.

In the case of DCGIS, charges invariably accumulate over a period of time along the spacer surface. Again, the electric field distribution around solid spacer is greatly altered by the accumulated surface charges. The breakdown strength of SF 6 gas is badly affected by locally enhanced electric field. Metal insert electrodes, which are used in GIS, reduce stresses near the triple junctions with simultaneous rise in the stresses elsewhere along the spacer surface. In this paper, the E-field distribution around two types of spacer configuration without and with metal insert electrodes have been studied. Effects of various parameters on the surface charge modified E-field have also been studied and presented.

The determination of transformer fault categories using soft-computing based techniques has been the subject of much research in the recent past. The development of an adaptive fuzzy classifier which can effectively determine various classes or categories of series and shunt impulse faults in a wide range of power transformers is described. The system employs a self-generating module to automatically derive a fuzzy rule base from predefined input and output memberslup functions (MFs) and a given data set for different fault classes. The accuracy of the system is further improved by translationally adapting output MF(s) either forward or backward, keeping their size and shape invariant. The database for different classes of faults is developed from FFT operation on current and voltage waveforms; obtained for different possible fault conditions simulated for given transformer models (EMTP) using an electromagnetic transients program. This database is used to create training and testing data sets required to design the fuzzy based classifier system. The usefulness of the proposed fuzzy based classifier is demonstrated on the basis of perfomances shown for four example Dower transformers of I MVA, 3MVA, SMVA and 60 MVA ratings

The pharmacokinetics of atracurium were studied in infants and children anaesthetized with isoflurane and nitrous oxide in oxygen. There were no significant differences in volume of distribution (area) (139 v. 152 ml kg-1), clearance (5.1 v. 5.3 ml kg-1 min-1), T1/2 alpha (2.1 v. 2.0 min), or T1/2 beta (19.1 v. 20.3 min) between children with normal hepatic and renal function and those with moderately impaired hepatic function presenting for hepatic transplantation. There were significant differences in volume of distribution (area) (176 v. 139 ml kg-1) and in clearance of atracurium (9.1 v. 5.1 ml kg-1 min-1) between infants and children with normal excretory function. In infants the clearance of atracurium in ml m-2 min-1 (153 v. 133) tended to be greater and the T1/2 alpha and T1/2 beta tended to be shorter (1.0 v. 2.0 and 13.6 v. 19.1) than in children with normal excretory function; however, these trends did not reach statistical significance. Plasma laudanosine concentration was around 100 ng ml-1 greater in patients with liver disease than in normal children from 15-45 min following a bolus of atracurium 0.5 mg kg-1.

The degradation of atracurium and the formation of laudanosine was examined in vitro in both Sorensen buffer and human plasma using sensitive, specific high pressure liquid chromatographic assays to determine drug concentrations. At normal physiological pH and temperature, the degradation of atracurium was threefold more rapid in plasma than in buffer. Laudanosine is the major end-product of atracurium degradation in buffer or in plasma; its production is more rapid in plasma than in buffer. Dilution of plasma constituents or the use of diisopropylfluorophosphate (a potent esterase inhibitor), slows the degradation of atracurium and the production of laudanosine. We conclude that, although ester hydrolysis is the major metabolic pathway of atracurium degradation, Hofmann elimination provides a "safety net" in its clinical use.

Bengal Immunity Research Institute, Calcutta-700017 Manuscript received 11 March 1976, revised 20 August 1976,accepted 14 February 1917 Quinoline Derivatives : Part XXI. Synthesis of Some 8-Hydroxyquinoline Derivatives as Possible Amoebicidal or Trypanocidal Agents.

The in vitro rates of metabolism of mivacurium chloride and succinylcholine in pooled human plasma were compared. In addition, the rate of metabolism of mivacurium in buffered solutions of butyrylcholinesterase (E.C. 3.1.1.8) and acetylcholinesterase (E.C. 3.1.1.7) was determined. Succinylcholine concentrations were measured spectrophotometrically, and mivacurium concentrations were determined with a high-pressure liquid chromatographic assay. The hydrolysis of mivacurium in plasma followed first-order kinetics, and the rate of hydrolysis decreased as plasma was serially diluted. The Michaelis-Menten constant (Km) for mivacurium metabolism in plasma was 245 mumol/L, and the maximum velocity (Vmax) was 50 U/L; the Km for succinylcholine was 37 mumol/L, and Vmax was 74 U/L. At comparable multiples of the Km the hydrolysis rate of mivacurium was 70% of that of succinylcholine. Mivacurium was metabolized significantly in solutions containing butyrylcholinesterase, but only minimally in solutions containing acetylcholinesterase.

Cimetidine increases the duration of action of succinylcholine several-fold by an unknown mechanism. The hydrolysis rate of succinylcholine by human plasma was measured with a modified spectrophotometric assay. At a concentration of 1-50 micrograms/ml cimetidine did not inhibit the hydrolysis of succinylcholine. It is concluded that cimetidine may have an effect at the neuromuscular junction but does not inhibit plasma cholinesterase.

THE use of 'Gammexane' has been recommended for controlling insect pests in libraries and record offices, where insect infestation is a serious problem especially in a tropical climate. 'Gammexane' smoke generators appeared to be particularly suitable for this purpose owing to the ease and safety with which they can be handled. But no information about its effect on paper1 was available, and the use of a new insecticide for the disinfestation of documents of a unique and irreplaceable nature had therefore to be scrutinized from the preservation point of view.

Cimetidine increases the duration of action of succinylcholine several-fold by an unknown mechanism. The hydrolysis rate of succinylcholine by human plasma was measured with a modified spectrophotometric assay. At a concentration of 1-50 micrograms/ml cimetidine did not inhibit the hydrolysis of succinylcholine. It is concluded that cimetidine may have an effect at the neuromuscular junction but does not inhibit plasma cholinesterase.

The in vitro rates of metabolism of mivacurium chloride and succinylcholine in pooled human plasma were compared. In addition, the rate of metabolism of mivacurium in buffered solutions of butyrylcholinesterase (E.C. 3.1.1.8) and acetylcholinesterase (E.C. 3.1.1.7) was determined. Succinylcholine concentrations were measured spectrophotometrically, and mivacurium concentrations were determined with a high-pressure liquid chromatographic assay. The hydrolysis of mivacurium in plasma followed first-order kinetics, and the rate of hydrolysis decreased as plasma was serially diluted. The Michaelis-Menten constant (Km) for mivacurium metabolism in plasma was 245 mumol/L, and the maximum velocity (Vmax) was 50 U/L; the Km for succinylcholine was 37 mumol/L, and Vmax was 74 U/L. At comparable multiples of the Km the hydrolysis rate of mivacurium was 70% of that of succinylcholine. Mivacurium was metabolized significantly in solutions containing butyrylcholinesterase, but only minimally in solutions containing acetylcholinesterase.