MMKK JAIN - Academia.edu (original) (raw)
Papers by MMKK JAIN
Numerical Methods for Partial Differential Equations, 2001
We report a new unconditionally stable implicit alternating direction implicit (ADI) scheme of O(... more We report a new unconditionally stable implicit alternating direction implicit (ADI) scheme of O(k2 + h2) for the difference solution of linear hyperbolic equation utt + 2αut + β2u = uxx + uyy + f(x, y, t), αβ ≥ 0, 0 < x, y < 1, t > 0 subject to appropriate initial and Dirichlet boundary conditions, where α > 0 and β ≥ 0 are real numbers. The resulting system of algebraic equations is solved by split method. Numerical results are provided to demonstrate the efficiency and accuracy of the method. © 2001 John Wiley & Sons, Inc. Numer Methods Partial Differential Eq 17: 684–688, 2001
Numerical Methods for Partial Differential Equations, 2001
... B0000( ¯Uj+1 yyl,m,n − ¯Uj−1 yyl,m,n) + C0000( ¯Uj+1 zzl,m,n − ¯Uj−1 zzl,m,n)] − k2 4 [A0001 ... more ... B0000( ¯Uj+1 yyl,m,n − ¯Uj−1 yyl,m,n) + C0000( ¯Uj+1 zzl,m,n − ¯Uj−1 zzl,m,n)] − k2 4 [A0001 ¯Uj xxl,m,n + B0001 ¯Uj yyl,m,n + C0001 ¯Uj zzl,m,n] (7.4) ¯¯Fj l,m,n = f(xl,ym,zn,tj,Uj l,m,n, ¯¯U j xl,m,n, ¯¯U j yl,m,n, ¯¯U j zl,m,n, ¯¯U j tl,m,n). (7.5) ...
Computational Mathematics and Modeling, 2013
Biochemistry, 1997
Mellitin, a cationic amphiphilic peptide, has an apparent activating effect on interfacial cataly... more Mellitin, a cationic amphiphilic peptide, has an apparent activating effect on interfacial catalysis by phospholipase A2 (PLA2) of bee venom on zwitterionic vesicles of 1-palmitoyl-2-oleoylglycero-sn-3-phosphocholine (POPC) and on anionic vesicles of 1,2-dimyristoylglycero-sn-3-phosphomethanol (DMPM), as well as on covesicles of POPC/DMPM (3:7). On the other hand, mellitin-induced increase in the rate of pig pancreatic PLA2 is seen only on anionic vesicles. Interfacial kinetic protocols and spectroscopic methods show that the activation is due to enhanced substrate replenishment resulting from intervesicle exchange of zwitterionic or anionic phospholipids through vesicle-vesicle contacts established by mellitin. It is shown that as the hydrolysis on POPC vesicles progresses, due to a high propensity of bee PLA2 for binding to the product containing zwitterionic vesicles, most of the enzyme in the reaction mixture is trapped on few vesicles that are initially hydrolyzed, and thus reaction ceases. Under these conditions, mellitin promotes substrate replenishment by direct exchange of the products of hydrolysis from the enzyme-containing vesicles with the substrate present in excess vesicles which have not been hydrolyzed. Pig PLA2 has poor affinity for POPC vesicles, and the affinity is only modestly higher in the presence of low mole fractions of the products of hydrolysis; therefore, the enzyme is not trapped on those vesicles. Biophysical studies confirm that the phospholipid exchange occurs through stable intervesicle contacts formed by low mole fractions of mellitin, without transbilayer movement of phospholipids or fusion of vesicles. At high mole fraction (> 1.5%) mellitin induces leakage in POPC vesicles and does not form additional contacts. In POPC/DMPM vesicles, the contacts are formed even at high mole fractions of mellitin. Changes in intrinsic tryptophan fluorescence of mellitin indicate that bound mellitin exists in at least two different functional forms depending on the lipid composition and on the lipid:peptide ratio. A model is proposed to accommodate amphiphilic mellitin as a transmembrane channel or an intervesicle contact.
Biochemistry, 1996
Structural specificity for the direct vesicle-vesicle exchange of phospholipids through stable mo... more Structural specificity for the direct vesicle-vesicle exchange of phospholipids through stable molecular contacts formed by the antibiotic polymyxin B (PxB) is characterized by kinetic and spectroscopic methods. As shown elsewhere [
Water Resources Management, 2008
The available antecedent moisture condition (AMC)-dependent runoff curve number (CN) (
Journal of Hydrologic Engineering, 2014
ABSTRACT This paper presents a relationship between the runoff curve number (CN) and mean potenti... more ABSTRACT This paper presents a relationship between the runoff curve number (CN) and mean potential evapotranspiration (PET) using long term daily rainfall-runoff data. To this end, CNs were derived for different durations from rainfall-runoff data of eight different agro-climatic river basins in India, and these were correlated with PET derived for respective watersheds using the standard Penman-Monteith method. The resulting high coefficient of determination (R2) values, viz, 0.99 for Hemawati and Mohegoan; 0.98 for Haridanagar, Kalu, and Seonath; 0.96 for Manot, Ghodahadho, and Ramganga strongly support the versatility of the derived relationship. This relationship also invokes determination of PET from the available published CN values, and therefore maybe quite useful in field applications. DOI:10.1061/(ASCE)HE.1943-5584.0000780. © 2014 American Society of Civil Engineers. Aut hor keyw ords: Curve number; National Engineering Handbook hydrology (NEH-4); Penman-Monteith; Potential evapotranspiration (PET); Soil conservation service; Water balance.
Numerical Methods for Partial Differential Equations, 2003
In this article, using a single computational cell, we report some stable two‐level explicit fini... more In this article, using a single computational cell, we report some stable two‐level explicit finite difference approximations of O(kh2 + h4) for ∂u/∂n for three‐space dimensional quasi‐linear parabolic equation, where h > 0 and k > 0 are mesh sizes in space and time directions, respectively. When grid lines are parallel to x‐, y‐, and z‐coordinate axes, then ∂u/∂n at an internal grid point becomes ∂u/∂x, ∂u/∂y, and ∂u/∂z, respectively. The proposed methods are also applicable to the polar coordinates problems. The proposed methods have the simplicity in nature and use the same marching type of technique of solution. Stability analysis of a linear difference equation and computational efficiency of the methods are discussed. The results of numerical experiments are compared with exact solutions. © 2003 Wiley Periodicals, Inc. Numer Methods Partial Differential Eq 19: 327–342, 2003.
Indian journal of psychiatry, 1980
A case of Insulinoma is presented here because of the uncommon and peculiar clinical manifestatio... more A case of Insulinoma is presented here because of the uncommon and peculiar clinical manifestation in the form of fits of unconsciousness with bizzare movements of limbs, which were considered to be due to Conversion Reaction and treated as such for a period of two years without any success. She recovered and was relieved of symptoms after surgery.
The Journal of the Association of Physicians of India, 2006
An unusual case of scorpion sting followed by multiple cerebral and cerebellar watershed infarcti... more An unusual case of scorpion sting followed by multiple cerebral and cerebellar watershed infarctions is being reported. Myocarditis, hypotension and hypoperfusion infarction is being considered as the possible explanation for this pathology. Hypoperfusion leading to parieto-occipital infarction has been reported earlier, however cerebellar infarction in this context is extremely rare.
Mathematics of Computation, 1974
Polynomials orthogonal on [ 0 , ∞ ] [0,\infty ] with regard to the weight function w ( x ) = x α ... more Polynomials orthogonal on [ 0 , ∞ ] [0,\infty ] with regard to the weight function w ( x ) = x α ( 1 + x ) − β w(x) = {x^\alpha }{(1 + x)^{ - \beta }} are obtained, recurrence relations are found and the differential equation, which is satisfied by them, is given. Formulas for weights and abscissas in the corresponding quadrature formula are given.
Water Resources Management, 2005
Flood problems resulting due to heavy rainfall and drainage congestion are being regularly experi... more Flood problems resulting due to heavy rainfall and drainage congestion are being regularly experienced in plain areas of Bihar, India. Due to this problem, power plant located in Koa catchment, Kahalgaon, Bihar, is faces huge loss at the time of flood. In this paper, the flood-affected areas in Koa catchment have been mapped using remote sensing satellite data (IRS LISS III, 1999 and Landsat TM, 1995). A range of image processing techniques has been used, including simple density slicing, Tasseled Cap Transformation and water-specific index. The results obtained using different approaches have been analysed. Result indicates that a Normalized Difference Water Index (NDWI) based approach produced best results.
Journal of the Physical Society of Japan, 1967
The steady state solution for the laminar flow of an electrically conducting liquid in the presen... more The steady state solution for the laminar flow of an electrically conducting liquid in the presence of transverse magnetic field has been investigated in detail. Taking into account the porosity of the walls we have obtained the velocity profiles for the induced magnetic and electric fields. Consideration has also been given to the rectangular channels in the following two cases:
Bioscience Reports, 1993
Sporidesmin, a mycotoxin from Pithomyces chartarum is a hydrophobic molecule. It can therefore be... more Sporidesmin, a mycotoxin from Pithomyces chartarum is a hydrophobic molecule. It can therefore be easily incorporated in the cell membrane, where it is likely to cause changes in the bilayer organization and the properties of membrane proteins. In order to understand the redox behaviour of sporidesmin in a hydrophobic environment, we have investigated the effects of oxidized and reduced sporidesmin on the phase transition properties of bilayers and on the susceptibility of bilayers to pancreatic phospholipase A2 (PLA2). The changes induced by sporidesmin in the thermotropic phase transition profiles of dimyristoyl-sn-3-phosphatidyl choline (DMPC) bilayers were similar to those caused by solutes known to localize in the glycerol-backbone region of the lipid bilayer, suggesting a similar localization for oxidized and reduced sporidesmin. Neither form of toxin disrupt the bilayer or membrane organization even at relatively high mole fractions. At concentrations <10 mole% both forms ...
This report was prepared as an account of work sponsored by the United States Government. Neither... more This report was prepared as an account of work sponsored by the United States Government. Neither the United States nor the United States Atomic Energy. Commission, nor any of their employees, nor any of i their contractors, subcontractors, or their employees, makes any warranty, express or implied, or assumes any legal liability or responsibility for the accuracy, completeness or usefulness of any information, apparatus, product or process disclosed, or represents that its use would not infringe privately owned rights.
Physiologia Plantarum, 1971
2.5 cm long stem segments of Populus nigra L. did not root when cultured in water or in auxins al... more 2.5 cm long stem segments of Populus nigra L. did not root when cultured in water or in auxins alone but rooted in glucose. The number of rooted segments and roots produced on them increased with rising glucose concentrations up to 0.5 "le, but decreased with higher concentrations. An addition of 1.0 mg/l IAA inhibited rooting at 0.01 "/o glucose, was ineffective at 0.1 "/o and stimulative at higher concentrations of glucose which were inhibitory when used alone. The results show that the auxin effects on rooting are influenced by the nutritional status of the stem cutting of a species, and that a proper balance of the two is necessary for root development.
Journal of Hydrology, 2012
ABSTRACT
Journal of Food Processing and Preservation, 1990
The keeping quality of synthetically flavored butter oil (FBOS) in comparison to butter oil (BO) ... more The keeping quality of synthetically flavored butter oil (FBOS) in comparison to butter oil (BO) and ghee (heat clarijied b u t t e~a t packaged in tin and polyethylene packages was evaluated organoleptically and by chemical tests viz. free fatty acids (FFA} level, peroxide value (PV}, total carbonyl content (TCC) and moisture content (MC). FBOS and BO had lower average flavor score (F S) , FFA level and MC and higher average PV and TCC than those in ghee. FBOS had higher average FS and PV than those in BO, variations in other parameters being nonsignijicant. The keeping quality of FBOS was intermediate between that of ghee and BO. Fats in tin containers had signgcantlv higher average FFA level, MC and lower PV than fats in polyethvlene containers. The variations in average TCC and FS in fats in tin containers and polyethylene containers were nonsignijicant. A firm generalized inference could not be drawn about the use of containers f o r the storage of' various fat samples. As the oxidative changes compared to hydrolytic changes are of greater signijicance in the deterioration of FBOS and BO, tin packages should be preferred to polyethylene packages for the storage of FBOS and BO.
Biochimica et Biophysica Acta (BBA) - Biomembranes, 1984
In a previous publication, (Singer, M.A., Jain, M.K., Sable, H.Z., Pownall, H.H., Mantulin, W.W.,... more In a previous publication, (Singer, M.A., Jain, M.K., Sable, H.Z., Pownall, H.H., Mantulin, W.W., Lister, M.D. and Hancock, A.J. (1983) Biochim. Biophys. Acta, 731, 373-377), we reported the properties of aqueous dispersions of the six diastereo-isomers of cyclopentanoid analogues of dipalmitoylphosphatidylcholine. Two of these isomers displayed unusually high enthalpies of transition, about double that of dipalmitoylphosphatidylcholine. One of the high enthalpy isomers whose configuration is all-trans has now been modified by the insertion of extra methylene residues (n = 3 through 9) between the nitrogen and phosphorus atoms of the headgroup. Vesicles were formed from these lipids and studied by 22Na permeability measurements, differential scanning calorimetry, fluorescence polarization, 31P-NMR, and freeze-fracture electron microscopy. Vesicles composed of lipids with n = 2 or 3 exhibit a sharp transition at 46 degrees C or 49 degrees C, respectively, and a high enthalpy with no detectable sub- or pretransitions. Lipids with n greater than 3 exhibit a main transition between 38 and 43 degrees C with enthalpies less than 10 kcal/mol and after prolonged coding (more than 3 days at 4 degrees C) a broad endotherm at about 20 +/- 3 degrees C with enthalpies greater than 4 kcal/mol. These same dispersions display a permeability peak at 20-25 degrees C and a second increase in 22Na efflux in the temperature range 30-40 degrees C. The results of 31P-NMR measurements suggest that the acyl chains in 2,3-dipalmitoylcyclopentano-1-phosphocholine (n = 2) bilayers have restricted rotation below the main phase transition temperature.
Numerical Methods for Partial Differential Equations, 2001
We report a new unconditionally stable implicit alternating direction implicit (ADI) scheme of O(... more We report a new unconditionally stable implicit alternating direction implicit (ADI) scheme of O(k2 + h2) for the difference solution of linear hyperbolic equation utt + 2αut + β2u = uxx + uyy + f(x, y, t), αβ ≥ 0, 0 < x, y < 1, t > 0 subject to appropriate initial and Dirichlet boundary conditions, where α > 0 and β ≥ 0 are real numbers. The resulting system of algebraic equations is solved by split method. Numerical results are provided to demonstrate the efficiency and accuracy of the method. © 2001 John Wiley & Sons, Inc. Numer Methods Partial Differential Eq 17: 684–688, 2001
Numerical Methods for Partial Differential Equations, 2001
... B0000( ¯Uj+1 yyl,m,n − ¯Uj−1 yyl,m,n) + C0000( ¯Uj+1 zzl,m,n − ¯Uj−1 zzl,m,n)] − k2 4 [A0001 ... more ... B0000( ¯Uj+1 yyl,m,n − ¯Uj−1 yyl,m,n) + C0000( ¯Uj+1 zzl,m,n − ¯Uj−1 zzl,m,n)] − k2 4 [A0001 ¯Uj xxl,m,n + B0001 ¯Uj yyl,m,n + C0001 ¯Uj zzl,m,n] (7.4) ¯¯Fj l,m,n = f(xl,ym,zn,tj,Uj l,m,n, ¯¯U j xl,m,n, ¯¯U j yl,m,n, ¯¯U j zl,m,n, ¯¯U j tl,m,n). (7.5) ...
Computational Mathematics and Modeling, 2013
Biochemistry, 1997
Mellitin, a cationic amphiphilic peptide, has an apparent activating effect on interfacial cataly... more Mellitin, a cationic amphiphilic peptide, has an apparent activating effect on interfacial catalysis by phospholipase A2 (PLA2) of bee venom on zwitterionic vesicles of 1-palmitoyl-2-oleoylglycero-sn-3-phosphocholine (POPC) and on anionic vesicles of 1,2-dimyristoylglycero-sn-3-phosphomethanol (DMPM), as well as on covesicles of POPC/DMPM (3:7). On the other hand, mellitin-induced increase in the rate of pig pancreatic PLA2 is seen only on anionic vesicles. Interfacial kinetic protocols and spectroscopic methods show that the activation is due to enhanced substrate replenishment resulting from intervesicle exchange of zwitterionic or anionic phospholipids through vesicle-vesicle contacts established by mellitin. It is shown that as the hydrolysis on POPC vesicles progresses, due to a high propensity of bee PLA2 for binding to the product containing zwitterionic vesicles, most of the enzyme in the reaction mixture is trapped on few vesicles that are initially hydrolyzed, and thus reaction ceases. Under these conditions, mellitin promotes substrate replenishment by direct exchange of the products of hydrolysis from the enzyme-containing vesicles with the substrate present in excess vesicles which have not been hydrolyzed. Pig PLA2 has poor affinity for POPC vesicles, and the affinity is only modestly higher in the presence of low mole fractions of the products of hydrolysis; therefore, the enzyme is not trapped on those vesicles. Biophysical studies confirm that the phospholipid exchange occurs through stable intervesicle contacts formed by low mole fractions of mellitin, without transbilayer movement of phospholipids or fusion of vesicles. At high mole fraction (> 1.5%) mellitin induces leakage in POPC vesicles and does not form additional contacts. In POPC/DMPM vesicles, the contacts are formed even at high mole fractions of mellitin. Changes in intrinsic tryptophan fluorescence of mellitin indicate that bound mellitin exists in at least two different functional forms depending on the lipid composition and on the lipid:peptide ratio. A model is proposed to accommodate amphiphilic mellitin as a transmembrane channel or an intervesicle contact.
Biochemistry, 1996
Structural specificity for the direct vesicle-vesicle exchange of phospholipids through stable mo... more Structural specificity for the direct vesicle-vesicle exchange of phospholipids through stable molecular contacts formed by the antibiotic polymyxin B (PxB) is characterized by kinetic and spectroscopic methods. As shown elsewhere [
Water Resources Management, 2008
The available antecedent moisture condition (AMC)-dependent runoff curve number (CN) (
Journal of Hydrologic Engineering, 2014
ABSTRACT This paper presents a relationship between the runoff curve number (CN) and mean potenti... more ABSTRACT This paper presents a relationship between the runoff curve number (CN) and mean potential evapotranspiration (PET) using long term daily rainfall-runoff data. To this end, CNs were derived for different durations from rainfall-runoff data of eight different agro-climatic river basins in India, and these were correlated with PET derived for respective watersheds using the standard Penman-Monteith method. The resulting high coefficient of determination (R2) values, viz, 0.99 for Hemawati and Mohegoan; 0.98 for Haridanagar, Kalu, and Seonath; 0.96 for Manot, Ghodahadho, and Ramganga strongly support the versatility of the derived relationship. This relationship also invokes determination of PET from the available published CN values, and therefore maybe quite useful in field applications. DOI:10.1061/(ASCE)HE.1943-5584.0000780. © 2014 American Society of Civil Engineers. Aut hor keyw ords: Curve number; National Engineering Handbook hydrology (NEH-4); Penman-Monteith; Potential evapotranspiration (PET); Soil conservation service; Water balance.
Numerical Methods for Partial Differential Equations, 2003
In this article, using a single computational cell, we report some stable two‐level explicit fini... more In this article, using a single computational cell, we report some stable two‐level explicit finite difference approximations of O(kh2 + h4) for ∂u/∂n for three‐space dimensional quasi‐linear parabolic equation, where h > 0 and k > 0 are mesh sizes in space and time directions, respectively. When grid lines are parallel to x‐, y‐, and z‐coordinate axes, then ∂u/∂n at an internal grid point becomes ∂u/∂x, ∂u/∂y, and ∂u/∂z, respectively. The proposed methods are also applicable to the polar coordinates problems. The proposed methods have the simplicity in nature and use the same marching type of technique of solution. Stability analysis of a linear difference equation and computational efficiency of the methods are discussed. The results of numerical experiments are compared with exact solutions. © 2003 Wiley Periodicals, Inc. Numer Methods Partial Differential Eq 19: 327–342, 2003.
Indian journal of psychiatry, 1980
A case of Insulinoma is presented here because of the uncommon and peculiar clinical manifestatio... more A case of Insulinoma is presented here because of the uncommon and peculiar clinical manifestation in the form of fits of unconsciousness with bizzare movements of limbs, which were considered to be due to Conversion Reaction and treated as such for a period of two years without any success. She recovered and was relieved of symptoms after surgery.
The Journal of the Association of Physicians of India, 2006
An unusual case of scorpion sting followed by multiple cerebral and cerebellar watershed infarcti... more An unusual case of scorpion sting followed by multiple cerebral and cerebellar watershed infarctions is being reported. Myocarditis, hypotension and hypoperfusion infarction is being considered as the possible explanation for this pathology. Hypoperfusion leading to parieto-occipital infarction has been reported earlier, however cerebellar infarction in this context is extremely rare.
Mathematics of Computation, 1974
Polynomials orthogonal on [ 0 , ∞ ] [0,\infty ] with regard to the weight function w ( x ) = x α ... more Polynomials orthogonal on [ 0 , ∞ ] [0,\infty ] with regard to the weight function w ( x ) = x α ( 1 + x ) − β w(x) = {x^\alpha }{(1 + x)^{ - \beta }} are obtained, recurrence relations are found and the differential equation, which is satisfied by them, is given. Formulas for weights and abscissas in the corresponding quadrature formula are given.
Water Resources Management, 2005
Flood problems resulting due to heavy rainfall and drainage congestion are being regularly experi... more Flood problems resulting due to heavy rainfall and drainage congestion are being regularly experienced in plain areas of Bihar, India. Due to this problem, power plant located in Koa catchment, Kahalgaon, Bihar, is faces huge loss at the time of flood. In this paper, the flood-affected areas in Koa catchment have been mapped using remote sensing satellite data (IRS LISS III, 1999 and Landsat TM, 1995). A range of image processing techniques has been used, including simple density slicing, Tasseled Cap Transformation and water-specific index. The results obtained using different approaches have been analysed. Result indicates that a Normalized Difference Water Index (NDWI) based approach produced best results.
Journal of the Physical Society of Japan, 1967
The steady state solution for the laminar flow of an electrically conducting liquid in the presen... more The steady state solution for the laminar flow of an electrically conducting liquid in the presence of transverse magnetic field has been investigated in detail. Taking into account the porosity of the walls we have obtained the velocity profiles for the induced magnetic and electric fields. Consideration has also been given to the rectangular channels in the following two cases:
Bioscience Reports, 1993
Sporidesmin, a mycotoxin from Pithomyces chartarum is a hydrophobic molecule. It can therefore be... more Sporidesmin, a mycotoxin from Pithomyces chartarum is a hydrophobic molecule. It can therefore be easily incorporated in the cell membrane, where it is likely to cause changes in the bilayer organization and the properties of membrane proteins. In order to understand the redox behaviour of sporidesmin in a hydrophobic environment, we have investigated the effects of oxidized and reduced sporidesmin on the phase transition properties of bilayers and on the susceptibility of bilayers to pancreatic phospholipase A2 (PLA2). The changes induced by sporidesmin in the thermotropic phase transition profiles of dimyristoyl-sn-3-phosphatidyl choline (DMPC) bilayers were similar to those caused by solutes known to localize in the glycerol-backbone region of the lipid bilayer, suggesting a similar localization for oxidized and reduced sporidesmin. Neither form of toxin disrupt the bilayer or membrane organization even at relatively high mole fractions. At concentrations <10 mole% both forms ...
This report was prepared as an account of work sponsored by the United States Government. Neither... more This report was prepared as an account of work sponsored by the United States Government. Neither the United States nor the United States Atomic Energy. Commission, nor any of their employees, nor any of i their contractors, subcontractors, or their employees, makes any warranty, express or implied, or assumes any legal liability or responsibility for the accuracy, completeness or usefulness of any information, apparatus, product or process disclosed, or represents that its use would not infringe privately owned rights.
Physiologia Plantarum, 1971
2.5 cm long stem segments of Populus nigra L. did not root when cultured in water or in auxins al... more 2.5 cm long stem segments of Populus nigra L. did not root when cultured in water or in auxins alone but rooted in glucose. The number of rooted segments and roots produced on them increased with rising glucose concentrations up to 0.5 "le, but decreased with higher concentrations. An addition of 1.0 mg/l IAA inhibited rooting at 0.01 "/o glucose, was ineffective at 0.1 "/o and stimulative at higher concentrations of glucose which were inhibitory when used alone. The results show that the auxin effects on rooting are influenced by the nutritional status of the stem cutting of a species, and that a proper balance of the two is necessary for root development.
Journal of Hydrology, 2012
ABSTRACT
Journal of Food Processing and Preservation, 1990
The keeping quality of synthetically flavored butter oil (FBOS) in comparison to butter oil (BO) ... more The keeping quality of synthetically flavored butter oil (FBOS) in comparison to butter oil (BO) and ghee (heat clarijied b u t t e~a t packaged in tin and polyethylene packages was evaluated organoleptically and by chemical tests viz. free fatty acids (FFA} level, peroxide value (PV}, total carbonyl content (TCC) and moisture content (MC). FBOS and BO had lower average flavor score (F S) , FFA level and MC and higher average PV and TCC than those in ghee. FBOS had higher average FS and PV than those in BO, variations in other parameters being nonsignijicant. The keeping quality of FBOS was intermediate between that of ghee and BO. Fats in tin containers had signgcantlv higher average FFA level, MC and lower PV than fats in polyethvlene containers. The variations in average TCC and FS in fats in tin containers and polyethylene containers were nonsignijicant. A firm generalized inference could not be drawn about the use of containers f o r the storage of' various fat samples. As the oxidative changes compared to hydrolytic changes are of greater signijicance in the deterioration of FBOS and BO, tin packages should be preferred to polyethylene packages for the storage of FBOS and BO.
Biochimica et Biophysica Acta (BBA) - Biomembranes, 1984
In a previous publication, (Singer, M.A., Jain, M.K., Sable, H.Z., Pownall, H.H., Mantulin, W.W.,... more In a previous publication, (Singer, M.A., Jain, M.K., Sable, H.Z., Pownall, H.H., Mantulin, W.W., Lister, M.D. and Hancock, A.J. (1983) Biochim. Biophys. Acta, 731, 373-377), we reported the properties of aqueous dispersions of the six diastereo-isomers of cyclopentanoid analogues of dipalmitoylphosphatidylcholine. Two of these isomers displayed unusually high enthalpies of transition, about double that of dipalmitoylphosphatidylcholine. One of the high enthalpy isomers whose configuration is all-trans has now been modified by the insertion of extra methylene residues (n = 3 through 9) between the nitrogen and phosphorus atoms of the headgroup. Vesicles were formed from these lipids and studied by 22Na permeability measurements, differential scanning calorimetry, fluorescence polarization, 31P-NMR, and freeze-fracture electron microscopy. Vesicles composed of lipids with n = 2 or 3 exhibit a sharp transition at 46 degrees C or 49 degrees C, respectively, and a high enthalpy with no detectable sub- or pretransitions. Lipids with n greater than 3 exhibit a main transition between 38 and 43 degrees C with enthalpies less than 10 kcal/mol and after prolonged coding (more than 3 days at 4 degrees C) a broad endotherm at about 20 +/- 3 degrees C with enthalpies greater than 4 kcal/mol. These same dispersions display a permeability peak at 20-25 degrees C and a second increase in 22Na efflux in the temperature range 30-40 degrees C. The results of 31P-NMR measurements suggest that the acyl chains in 2,3-dipalmitoylcyclopentano-1-phosphocholine (n = 2) bilayers have restricted rotation below the main phase transition temperature.