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"This book describes the origins and evolution of the chemical elements we and the cosmos are made of. The story starts with the discovery of the common elements on Earth and their subsequent discovery in space. How do we learn the composition of the distant stars? How did progress in quantum theory, nuclear physics, spectroscopy, stellar structure and evolution, together with observations of stars, converge to provide an incredibly detailed picture of the universe? How does research in the micro-world explain the macro-world? How does progress in one affect the other, or lack of knowledge in one inhibit progress in the other? In short, Shaviv describes how we discovered the various pieces of the jigsaw that form our present picture of the universe, and how we sometimes put these in the wrong place before finding in the right one.En route we meet some fascinating personalities and learn about heated controversies. Shaviv shows how science lurched from one dogma to the next, time and again shattering much of what had been considered solid knowledge, until eventually a stable understanding arose. Beginning with generally accepted science, the book ends in today’s terra incognita of nuclear physics, astrophysics and cosmology. "

"Senyawa kimia yang terkandung dalam kulit batang tumbuhan jawura (Garcinia lateriflora BL ) diekstraksi dengan n-heksana. Senyawa tersebut diisolasi dengan cara kromatografi kolom cepat (flash column chromatography) dengan larutan pengelusi campuran n-heksana : EtOAc, yang polaritasnya dinaikan secara bertahap.Dari fraksi 11-13 diperoleh senyawa GA, kristal jarum berwarna putih, transparan sebanyak 10 mg. Dari fraksi 20-22 diperoleh senyawa GB merupakan kristal jarum berwarna kuning, transparan sebanyak 300 mg.Struktur molekul senyawa GA dan GB ditentukan berdasarkan data spektroskopi (inframerah, FAB-MS, 1H-NMR, 13C-NMR serta spektra dua dimensi) dan difraksi sinar- X. Dari data spektroskopi diketahui, bahwa senyawa GA adalah stigmasterol, dengan rumus molekul C29H46D (8M=412), sedangkan senyawa GB merupakan turunan benzoquinon dengan rumus molekul C33H3809 (BM=578), adalah suatu senyawa Baru yang diberi nama laterimasoton.Daftar pustaka 20 0981-1997)

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Chemical constituents contained in the stem bark of Jawura (Garcinia laterilora BL) were extracted by n-hexane, the compounds were separated and isolated with flash column chromatography using silica gel as the stationary phase, n-hexane and ethyl acetate as the mobile phase.

From 11-13 fraction was given rise GA compound, as white needle crystal, weight 10 mg. And from 20-23 fraction was isolated GB compound as yellow needle crystal, weight 300 mg. The structure of GA and GB were established using spectroscopy data (IR, 1H-NMR, 13C-NMR with 2D and X-ray diffraction).

Based on spectroscopy data the GA compound was identified as stigmasterol with formula molecular C29H480 (Mr = 412), while the GB compound was established as benzoquinon derivative with formula C33H3809 (Mr = 578), the GB compound is a new compound, named laterimasoton."

"Tujuan Mengetahui efektifitas krim EMLA dalam mengurangi kekerapan dan derajat nyeri saat dilakukan pungsi epidural.Metode Up Klinik Acak Ganda Penelitian dilakukan di Insta1asi Bedah Pusat RSCM pada bulan Februari sampai dengan Maret 2006 dengan jumlah sampel 64 pasien dewasa yang menjalani operasi berencana dan anestesia epidural Pasien dibagi secara acak ke dalam 2 kelompok 32 pasien mendapatkan 2 5 gram krim EMLA dioleskan pada daerah L45 90 menit sebelum dilakukan pungsi epidural dan 32 pasien lainnya mendapatkan 20 mg Lidokain infiltrast 2 menit sebelum pungsi epidural Dilakukan pencatatan nilai Visual Analogue Scale dan derajat nyeri secara obyektifsaatjarum epidural mencapai kedalaman 0 5 1 cm dan permukaan kulit dan pada saat engaged Analisa statistik untuk melihat perbedaan kekerapan antara kedua perlakuan menggunakan up Chi Square sedangkan untuk membandingkan derajat nyeri kedua perlakuan menggunakan up Kolmogorov Smirnov.Hasil Tidak terdapat perbedaan yang bermakna secara statistik antara kedua kelompok perlakuan dalam hal kekerapan dan derajat nyeri yang dihasilkan saat pungsi epidural.

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Objective To observe the effectiveness of EMLA cream in reducing the frequency and degree of pain in epidural punctureMethods Non blinded randomized clinical trial The study was conducted at Cipto Mangunkusumo Hospital Central Surgery Room from February until March 2006 to 64 adult patients who went to elective surgery and were planned to be under epidural anesthesia Patients were divided randomly into two groups The EMLA group was consist of thirty two patients rubbed with 25 gram EMLA cream on their L45 area ninety minutes before the epidural puncture began The other thirty two patients was infiltrated with 20 mg Lidocaine two minutes before the epidural puncture. When the epidural needle-puncture reached the depth 0f05 1 cm from the skin surface and when engaged Visual Analogue Scale and degree ofpazn was recorded objectively Chi Square method was performed to identify the frequency difference between the two groups While at the same time Kolmogorov-Smirnov method was also performed to identify the degree of pain difference between the two groups.Conclusion There were no significant statistical differences between the two groups in a matter offrequency and degree ofpazn in epidural puncture"

"Sintesis polimer hibrid lateks dengan teknik polimerisasi miniemulsi dengan menggunakan montmorillonite sebagai filler telah dilakukan. Montmorillonite dipilih sebagai filler karena memiliki struktur kimia yang jelas serta aspek rasio dan luas permukaan yang besar. Untuk merubah sifat montmorillonite yang hidrofilik menjadi hidrofobik, telah dilakukan proses modifikasi dengan menggunakan senyawa alkilammonium dengan rantai atom alkil yang berbeda, yakni dengan DTAB, CTAB dan OTAB. Modifikasi dilakukan dengan menggunakan proses pertukaran ion dengan rasio 2.0 CEC. Modifikasi dengan senyawa alkilammonium dengan rantai atom yang berbeda tidak menunjukkan adanya perbedaan yang signifikan terhadap perubahan pada pola difraksi XRD dan FTIR. Perbedaan hanya ditemukan pada termal dekomposisinya, dimana MMT-OTAB menunjukkan termal kestabilan yang lebih baik dibandingkan dengan yang lain, sehingga MMT-OTAB digunakan sebagai bahan pengisi untuk proses polimerisasi. Pilarisasi terjadi dengan pergeseran sudut 2Ɵ dari ke dan basal spacing d001 meningkat dari 12.1Å ke 21.0Å dan membentuk struktur pseudotrilayer. FTIR mendukung hasil XRD dengan indikasi masuknya gugus alkil ke dalam interlayer dan permukaan MMT.Inisiator AIBN merupakan inisiator yang paling sesuai untuk digunakan pada sintesis polimer hibrid lateks karena memiliki indeks kelarutan yang paling tinggi dan pengukuran DTG menunjukkan nilai asimetrik yang tinggi yakni C, surfaktan yang paling sesuai untuk digunakan pada proses polimerisasi miniemulsi adalah surfaktan yang larut dalam air yakni SDS. Sintesis polimer hibrid lateks dengan OMMT membentuk kopolimer yang memiliki sifat barrier yang lebih baik bila dibandingkan dengan polimer murni.OMMT dengan loading rasio 8.0 wt % menunjukkan ketahanan barrier yang sama dengan polimer sintetik LDPE, Poliester dan EVOH. OMMT dengan loading rasio 10.0 wt % akan menghasilkan ketahanan barrier yang sama dengan PET. Sintesis polimer hibrid lateks dengan OMMT level 10.0 wt % sulit dilakukan karena terjadinya ketidakstabilan dan agglomerasi sewaktu proses polimerisasi.

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Sinthesis polimer hybrid latex was done by miniemulsion polymerization technique using montmorillonite as filler. Montmorilloniate was selected as filler due to its high aspect ratio and high surface area and also well known chemical structure. To change the nature of montmorillonite bhevavior from hydrophilic to organophilic, cationic exchange process was done with different alkyl chains of alkylammonium bromide surfactants (DTAB, CTAB and OTAB with ratio 2.0 CEC. To change the hydrophilic behavior of montmorillonite to organophilic, surface modification of montmorillonite was performed by alkylammonium bromide with different alkyl chains. Modification process was performed based on ionic exchange process with 2.0 CEC ratio.

Modification with different alkyl chains alkylammonium bromide (DTAB, CTAB and OTAB) did not shown an significant differences in diffraction pattern of XRD and FTIR. Thermal decomposition with TGA shown MMT-OTAB has a better thermal decomposition compare to others, as it is used a basic for selection as a filler in polymerization processs. Pilarization was happened when the 2Ɵ angle from d001 was shifting to lower position from to and basal spacing of d001 increase from 12.1Å to 21.0 Å and formed pseudotrilayer structure. FTIR supported the XRD results, indicated alyl group of surfactant has been inserted into clay interlayer or surface of MMT

Initiator AIBN was selected as inisiator for miniemulsion polymerization for synthesis polymer hibrid latex due to its high solubility index and from DTG measurement shown high asymmetric temperature C. Water soluble SDS surfactant was also selected as surfactant for miniemulsion polymerization.

Synthesis polimer hibrid latex with OMMT as filler formed a co-polymer with a better in barrier properties compare to pure polymer latex. Addition of OMMT up to 8.0% shown a barrier effect as similar to LDPE, Polyester and EVOH. Increasing the addition level to 10.0% could improve the barrier properties similar to PET but it is difficult to synthesized polimer hybrid latex with 10.0% OMMT level due to latex unstability and polymerization difficulty."