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راما نجم

مسٹر رامانجم

            اس وقت دنیا کا سب سے بڑا ریاضی دان ایک ہندوستانی تھا، مسٹر رامانجم کی بابت، جس کے کمالات ریاضیہ کا ذکر آج سے ٹھیک ایک سال قبل معارف میں آچکا ہے، بعض علماء فن کا خیال تھا کہ نیوٹن کے بعد سے دنیا میں اس دماغ کا ریاضی دان نہیں پیدا ہوا ہے اور اس کا تو سب کو اعتراف تھا کہ انھوں نے بعض وہ مسائل حل کردیئے جو پوری ایک صدی سے لاینحل چلے آرہے تھے، سخت افسوس ہے کہ ماہ گذشتہ میں اسی ہستی نے دق میں مبتلا ہوکر دنیا کو اپنے فیض سے ہمیشہ کے لئے محروم کردیا، مرحوم کا سن کل ۳۲ سال کا تھا۔

خوش درخشید ولے دولت مستعجمل بود

(جون ۱۹۲۰ء)

مدراس کے نامور ریاضی دان رامانجم کی خبر وفات کسی پچھلے معارف میں درج ہوچکی ہے، یورپ کے اعلیٰ علمی رسائل مدت تک ان کے ماتم میں سوگوار رہے، اور متعدد ماہرین فن کے قلم نے اس حادثہ عظیم پر علم و فن کی جانب سے فریضۂ تعزیت ادا کیا، کیمبرج یونیورسٹی کے مشہور پروفیسر جی،ایچ، ہارڈی نے سائنٹفک ہفتہ وار نیچر میں جو تعزیت نامہ شائع کیا ہے، اس میں بار بار اس قسم کے فقرہ ملتے ہیں۔ ’’یہ بالکل یقینی ہے کہ مرحوم کی مہندسانہ فضیلت اعلیٰ ترین پایہ کی تھی اور وہ ایک استشنائی قوت فکر و اجتہاد کا شخص تھا‘‘۔ اس کے تقریباً بیس مقالات شائع ہوئے، جنھوں نے زمانۂ جنگ ہی میں تمام دنیائے ریاضیات کو اپنی جانب متوجہ کرلیا‘‘۔ اس کے پیش نظر صرف وہ مسائل تھے، جن تک معدددے چند افراد کی رسائی ہوسکتی ہے‘‘۔ اس کی قوت استنباط بالکل حیرت انگیز تھی، جس کی کوئی نظیر کسی یوروپین ریاضی دان میں...

معالم السنن میں امام خطابی كا منہج و اسلوب

The status of Ma'Iim-us-Sunan is very high in explanations of Sunan Abu Dawood because it is considered first an explanation of Sunan Abu Dawood. Imam Khattabi has adopted such a fine method in it that with the literal explanation of words and description of jurisprudential commandments, he has also collected in it sayings ofSalaf-us-Saalih, Arabian proverbs, different opinions of various scholars, grammatical rules and Jarh-o-ta'deel etc. To add, he, as a specially, Ahadith and quotations ofSahabah and scholars, has made provision to describe his chain of narrators. Due to this, the book has adopted the basic primary status of Hadith knowledge. And further, because of these chains of narrators, this book has adopted the form of reference source in matters of teachers' identification of Imam Khattabi. Due to all these qualities undoubtedly the way this book was a need of scholars and researchers of every era, in the same way, scholars can never be exempted from this today.

Bitrophic Effects of Artificial Diets of American Bollworm Helicoverpa Armigera H. on Different Biological Aspects of Bracon Hebetor Say

Helicoverpa armigera (Hubner) is a notorious pest of various fields and horticultural crops worldwide. Insecticides application ultimately responsible for resistance development in H. armigera, unsafe for the environment and natural enemies of insect pests. To withstand the pesticides resistance, biological control successfully helps in reducing pest population. Bracon hebetor is a cosmopolitan species that have the ability to parasitize a wide range of lepidopteran and few coleopteran hosts. As H. armigera fed on wide host range so, quality and quantity of food nutrients provided at the time of Bracon hebetor larval development is a crucial step. The need of the current research project is to focus on which best suited semi-synthetic artificial diet of H. armigera; B. hebetor developmental parameters are good and further, how it can effectively be used under the scenario of ecological conditions after getting reared on efficient host for the control of H. armigera. So we can utilize B. hebetor as an efficient biological control agent for H. armigera management. Study objectives were to screen out the best suited artificial diet of H. armigera for the rearing of B. hebetor. Investigation of B. hebetor life history traits on most efficient hosts from the screened host species for the effective rearing of B. hebetor. Determination of the effect of temperature, relative humidity regimes and host larval densities on the life history traits of B. hebetor parasitizing H. armigera. B. hebetor parasitization, reproduction, development, fitness related traits and life table parameters were observed on different pyralids, noctuids, gelechiids and curculionids under laboratory conditions (25±2°C and 70±5%) in order to find out the most suitable host for the mass rearing and inundative release purposes to control H. armigera. Results indicated that among four semi-synthetic diets (gram, rice, wheat and corn) of H. armigera, gram flour mediated diet was responsible for good biological and developmental parameters of B. hebetor under laboratory conditions. It can be successfully used for the rearing of H. armigera as a host for good parasitism and development of B. hebetor. Though, H. armigera itself was not an excellent host for the continuous rearing of parasitoid therefore, seven different hosts (six from Lepidoptera and one Coleoptera) were utilized to screen out the suitable one. Results showed that the pyralids hosts (E. kuehniella, C. cephalonica and G. mellonella) gave the best results for daily fecundity, parasitoid survival to adulthood, development time and female biased sex ratio followed by H. armigera and the worst reproduction occurred on H. postica. Among the most efficient screened pyralid hosts, B. hebetor biological parameters and fitness related traits were excellent on E. kuehniella as compared to C. cephalonica. So production of good fitness traits (wing area, tibia size and dry mass), excellent biological parameters (good immature numbers and adults emergence), short egg-adult development time and changes in THCs provide a good means for the immature development of B. hebetor within the parasitized E. kuehniella for several days. Temperature relative humidity regimes and H. armigera larval densities significantly affect the biological and developmental parameters of B. hebetor. Excellent life history parameters of B. hebetor parasitizing gram diet fed H. armigera were observed at 25°C and 60% R.H. combination. Among various larval densities of H. armigera good biological parameters of B. hebetor like production of immature numbers, short egg-adult development time, survivorship and female progeny production was significantly good on five larval density of H. armigera offered for parasitization. Therefore, it is recommended that gram mediated diet is best suited for the rearing of H. armigera in order to find out the best suited temperature, humidity combination and host larval density in the field release planning and maintenance of B. hebetor population for long term field crops management to control H. armigera. On the other hand B. hebetor quality progeny production on E. kuehniella make this insect of great potential to serve as valuable material for laboratory rearing and inundative field release to control H. armigera larval populations.
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