In this research project thirty three new polyimides (PI-1 – PI-33) were synthesized from two series of diamines by polymerization with commercially available dianhydrides, pyromellitic dianhydride (PMDA), 4,9,10-perylenetetracarboxylic acid dianhydride (PD) and 3,3’,4,4’-benzophenonetetracarboxylic acid dianhydride (BD). Two series of diamines having azomethine (Series-I) and azomethine with ether linkage (Series-II) with aliphatic substituent’s like –CH3, -OH, -OCH3, -Cl were synthesized. The polyimides were synthesized by a conventional two steps method which involves the ring opening polyaddition at room temperature followed by the imidization either by thermal or chemical methods. All the synthesized diamines and polyimides were characterized by using different techniques like elemental analysis, TGA, FT-IR and 1H-NMR. All the spectral data were found in good agreement with the proposed structures of polyimides. These synthesized polyimides were also subjected for the study of organosolubility, inherent viscosity, molecular weight measurement, moisture absorption, thermal behaviour, crystallinity and thermodynamic parameters. The organosolubility of the synthesized polyimides were checked in different solvents qualitatively. The majority of the polyimides were found soluble in common polar aprotic solvents like m-cresol, dimethyl sulfoxide (DMSO), dimethylformamide (DMF), N,Ndimethylacetamide , tetrahydrofuran (THF) and sulphuric acid at room temperature as well as some of them were soluble on heating. The improvement in the oraganosolubility of the polyimides might be due to the presence of aliphatic substituents and ether linkages in the backbone of the polyimides which reduced the chain-chain interactions and hence enhance the chances of penetrating solvent molecules into polyimide chain. The inherent viscosities were found in the range of 0.59 – 0.85 dLg-1 indicating the moderate to higher molecular weight of polyimides. Weight average molecular weight (Mw) and number average molecular weight (Mn) of the polyimides were found in the range of 59,000 – 86,000 gmol-1 and 36,000 - 53,000 gmol-1 respectively. Moisture absorption capacity of the polyimides was found in the range of 0.38 - 0.89%. The moisture absorption capacity of the polyimides is greatly influenced by the chemical structure of polyimides. The polyimides exhibited excellent thermal properties having glass transition temperature g in the range of 220 – 292°C and the 10% weight loss temperature were above 400°C without significant weight losses up to 360°C. The polyimides PI-23 – PI-33 having 3,4,9,10-perylenetetracarboxylic acid dianhydride (PD) showed better thermal stability due to the rigid structure of dianhydride. Most of the polyimides displayed amorphous pattern in X-ray diffraction analysis. The polyimides of 3,3’4,4’-benzophenonetetracarboxylic acid dianhydride (BD) and pyrromellitic dianhydride (PMDA) units with azomethine linkage having aliphatic moieties diamines displayed semi-crystalline pattern. The values of thermodynamic parameters , activation energy, enthalpy and entropy fall in the range of 31– 54 kJmol-1, 29 – 52 kJmol-1 and 0.15 to 0.26 kJmol-1K-1 respectively. Due to improved solubility and better thermal stability these polyimides could be applicable for high performance polymeric materials applications like high temperature application, as heat resistant polyimide materials, in the synthesis of plastic materials, in organic materials, in magnetic materials, etc.
آوارگی تمہیں فرصت ہو تو۔۔۔ذرا دیکھو۔۔۔! لہریں تڑپتی رہتی ہیں بادبانوں سے گلے ملتے ہوئے، ہوائیں چلتی رہتی ہیں جواز صلیب کی ارغوانی خانقاہوں کا۔۔۔! میں کیسے گمشدہ لفظوں کی امید بن کر طواف کرتا ہوں کہیں تاثیر قیس بن کر۔۔۔! کہیں عزیز حسن بن کر۔۔۔! رات کے پچھلے پہر آہوانِ راز کی طرح دلفریب خوشبو میں قلندرانہ رقص کرتا رہتا ہوں۔۔۔! سعد ستاروں کی وصل زاد آواز کی طرح! دشت و بیابان میں۔۔۔فرشتوں کی حویلی میں! منتظر سبز بانہوں میں! سرخ نصاب کا یقیں بن کر رہتا ہوں پورب کی لالی سے۔۔۔پچھم کی لالی تک۔۔۔! فقیروں میں اپنی جاگیر تقسیم کرتے ہوئے!
بھید کے ہراساں نقشے میں! میں اپنے لہو سے رنگ بھرتے ہوئے! زخمی ناقہ ٔلذت کا پھٹا محمل رفو کرتا ہوں گلابوں میں سوسن و نسترن سجاتے ہوئے! زعفرانی کھیتوں میں! گمنام جزیروں سے چمپا اور چنبیلی بلاتے ہوئے! پھول چنتی دھڑکنوں میں چراغ بن کے جلتا رہتا ہوں نرم استعاروں میں آوارگی کی تشریح کرتا رہتا ہوں
Humans have always had the curiosity to know themselves, to know the world around them, and to know their place in the world. Morality, spirituality and religion are closely intertwined, ‘certain moral ideas became united with certain religious and spiritual ideas to such an extent as to become indistinct from them’. The role of religion in educational institutions is one of the most sensitive and volatile topics on the political and legal landscape now a days especially in country like Pakistan which has been created on religious ideology. The Islamic Way of Life is based on this unique approach to life and a peculiar concept of man's place in the Universe. Islam has provided mankind with the highest possible standard of morality. This moral code, which is both straightforward and practical, provides the individual with innumerable ways to embark upon and then continues the path of moral evolution. By making divine revelation the primary source of knowledge, moral standards are made permanent and stable. The first part of the paper is about the relationship between education and its role as spiritual and moral tool of training. Second part deals with the concept of education in Islam and third part will present types of knowledge in Islam and their application as moral and spiritual tool of education. Last part will give moral and spiritual training methodology in Islamic education. The relationships between ‘moral’, ‘spiritual’ and ‘religious’ seem to be akin to the relationships between the cluster ‘social’, ‘human’ and ‘political’. In each of these clusters, only beings of the kind appropriately described by the middle term can engage in activities which could be properly described by the first and third terms. Islam as religion of spirituality and morality gives a frame work to educate and train the students in modeling their life as more moral and spiritual with practical application in this life and success in the hereafter. The chief characteristic of the Islamic Concept of Life is that it does not admit a conflict, nay, not even a significant separation between life-spiritual and life-mundane. It does not confine itself merely in purifying the spiritual and the moral life of man in the limited sense of the word. Its domain extends to the entire gamut of life. It wants to would individual life as well as the social order in healthy patterns, so that the Kingdom of God may really be established on the earth and so that peace contentment and well-being may fill the world as water f ills the oceans.
Cardiovascular diseases, especially the hypertension, have been a global threat for the last few decades because of non-curative effects of the available synthetic drugs and their high economic burden on the patients as their treatment requires lifelong use of drugs. Therefore, alternate effective and economical treatment options are urgently needed to be explored from all possible resources. Since ancient times plants have been utilized for treating various ailments and even some drugs have been derived from the traditionally used plants. This part of the world has been blessed with diverse medicinal flora that has been widely used on empirical folkloric basis. Due to these reasons, three medicinal plants claimed to be effective and curative for certain cardiovascular diseases were selected for the present investigations. The study consists of evaluation of antihypertensive, cardiac depressant and vasorelaxant effects of aqueous-methanolic (aq-meth) extracts and certain fractions of three indigenous medicinal plants viz. Sonchus asper, Linn. (aerial-parts), Pennisetum glaucum, Linn. (seeds) and Zanthoxylum armatum, DC. (fruits). The results obtained showed that aq-meth extracts of all three plants have significantly decreased the systolic blood pressure (SBP), mean arterial pressure (MAP) and diastolic blood pressure (DBP) and also reduced the heart rates of normotensive rats in the dose and time dependent manner. Further studies were carried out on the glucose and egg yolk fed hypertensive rats. The aq-meth extracts of all the three test plants were found to significantly prevent the diet-induced rise in blood pressure parameters as well as the heart rates of aq-meth extract treated rats. Acute toxicity study showed safety of the extracts as their LD50s in mice were quite high i.e., 3500 and 3000 mg /kg p.o., for the aq-meth extracts of S. asper and Z. armatum, respectively. While no mortality occurred with oral administration of P. glaucum extract upto 4000 mg/kg dose, so no LD50 was calculated for aq-meth extract of P. glaucum. In subchronic toxicity testing, non-significant changes were observed in liver ezymes and lipid profile parameters of treated rats. These data have clearly demonstrated that the test plants’ extracts do not possess significant amount of toxic substances. Therefore, investigations were further extended to determine their active fraction (s) and possible mechanism (s) of action. For this purpose, aq-meth extracts of S. asper (aerial-parts) and P. glaucum (seeds) were fractionated into ethyl acetate, butanolic and aqueous fractions while a polyphenolic compound, tambulin already reported to be present in Z. armatum (fruits) was isolated for further experiments. In isolated perfused rabbit hearts, the extracts, fractions and tambulin were found to significantly decrease the force of contraction, perfusion pressure and heart rate. Ethyl acetate fraction of S. asper and butanolic fraction of P. glaucum among their tested fractions showed more pronounced effects on the cardiac parameters. Then studies were conducted on porcine coronary artery rings and it was observed that aq-meth extracts, fractions and tambulin produced a dose dependent similar vasorelaxant effects in U46619 pre-contracted endothelium-intact as well as denuded artery rings. However, endothelium removal was not found to significantly affect their vasorelaxant potencies indicating the endothelium-independent effect. Interestingly, the effects of ethyl acetate fraction of S. asper and butanolic fraction of P. glaucum were more marked in this respect, too. Therefore, these fractions were selected for futher study in order to find possible mechanism (s) of their vasorelaxant effects. The tambuin (10 µM) produced 100% relaxation of intact and denuded coronary artery rings and was subjected to further series of experiments along with other potent fractions i.e., ethyl acetate fraction of S. asper and butanolic fraction of P. glaucum. It was observed that the response curves of the endothelium-dependent vasodilating agents including bradykinin and calcum ionophore were not shifted by the test fractions and tambulin showing that their relaxant effect was endothelium-independent and the effect was governed by the vascular smooth muscles. It was also found that ethyl acetate fraction of S. asper (0.01 mg/ml), butanolic fraction (0.03 mg/ml) of P. glaucum and tambulin (1µM) produced shifting of concentration response curves of the endothelium-independent vasodilators including, sodium nitroprusside (SNP), forskolin (FC) and isoproterenol. The experiments also showed that the test fractions and tambulin did not shift response curves produced by soluble guanyly cyclase (sGC) activators (YC-1 and BAY 41-2272) and K+ channel openers (levchromakalim and 1-EBIO). However, pretreatment with EAFS, BFPG and tambulin suppressed in dose dependent fashion the cumulative contractile responses of endothelium-denuded coronary artery rings induced by KCl, 5-HT, CaCl2 and U46619. Further, experiments were carried out to study the role of c-AMP and c-GMP on the vasorelaxant effect of the test fractions and tambulin. Specific inhibitors of PKA and PKG, namely H-89 and Rp-8-br-cyclic GMPS were used to inhibit the c-AMP and c-GMP elevation, respectively. The relaxations produced by the EAFSA and tambulin were observed to have significantly reduced in the coronary artery rings that were exposed to H-89 (10 µM) and Rp-8-br-cyclic GMPS (30 µM) whereas the relaxant effect of the BFPG was more significantly decreased by Rp-8-br-cyclic GMPS as compared to H-89. The qualitative phytochemical studies on the ethyl acetate fraction of Sonchus asper (aerialparts) and butanolic fraction of Pennisetum glaucum (seeds) showed that saponins, terpenoids, flavonoids, tannins and alkaloids are contained by them. HPLC studies of the test fractions showed the existance of quercetin, gallic acid, caffic acid, vanillic acid, and ferulic acid in both the test plants’ fractions where as chlorogenic acid, m-coumaric acid and synapic acid were detected in ethyl acetate fraction of S. asper while p-coumaric acid and ginamic acid were contained in butanolic fraction of the P. glaucum. It is conceivable, therefore, that the test medicinal plants, namely Sonchus asper (aerial-parts), Pennisetum glaucum (seeds) and Zanthoxylum armatum (fruits) empirically used in folkloric medicine to treat various cardiovascular diseases do contain compounds that are able to produce antihypertensive effects. Current findings have also suggested that the reported antihypertensive effect might have resulted from vasorelaxation produced by elevation of c-AMP and/or c-GMP levels in the vasculature. However, inhibition of calcium influx, prevention of calcium mobilization from sarcoplasmic reticulum into the cytoplasm, negative ionotropic and chronotropic effects on the heart and the prevention of the oxidative stress by test fractions could also be responsible for their antihypertensive property. Phytochemical analyses of these plants’ potent fractions have shown that no single chemical compound can be held responsible for the reported activities as several chemical entities have been detected in them. Furthermore, comprehensive chemical and pharmacological studies should be planned to isolate active principles, identify their chemical structure and elucidate exact mechanism (s) of the antihypertensive effect of tested plants. In the meantime, tambulin isolated from Zanthoxylum armatum (fruits) could be suggested as its major active antihypertensive principle. The results substantiate the antihypertensive activity of the indigenous medicinal plants and their fractions. May be here lies the role that the traditional system of medicine has to play in advancing