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"Manusia memerlukan antioksidan untuk mencegah terjadinya stres oksidatif yang dapat menyebabkan gangguan fungsi kulit yaitu hiperpigmentasi kulit. Peristiwa tersebut berhubungan dengan aktivitas enzim tirosinase yang berkontribusi dalam pembentukan pigmen melanin kulit sehingga diperlukan penghambatan enzim tirosinase untuk menjaga kulit tetap cerah. Tanaman belimbing wuluh (Averrhoa bilimbi L.) yang berasal dari famili Oxalidaceae, merupakan salah satu tanaman yang digunakan sebagai obat tradisional. Daun belimbing wuluh terbukti sebagai sumber antioksidan dan anti-tirosinase alami. Penelitian ini bertujuan untuk mengidentifikasi fragmen pengenal dan jaringan khas dari simplisia, persentase rendemen, persentase kadar air, aktivitas antioksidan, dan aktivitas anti-tirosinase. Pengujian mikroskopik dilakukan menggunakan mikroskop cahaya. Daun belimbing wuluh diekstraksi secara maserasi dengan pelarut etanol 70%. Pengujian aktivitas antioksidan metode ABTS dengan standar asam askorbat dan penghambatan enzim tirosinase yang berasal dari jamur spesies Agaricus bisporus dengan standar asam kojat dan substrat L-DOPA yang dianalisa menggunakan microplate reader. Hasil pengamatan mikroskopik diperoleh rambut penutup, epidermis atas dengan dinding yang sedikit berkelok, epidermis bawah dengan dinding yang berkelok disertai stomata dan rambut penutup, stomata tipe parasitik, urat daun, dan pembuluh kayu dengan penebalan tangga. Rendemen hasil ekstraksi diperoleh dari metode maserasi sebesar 21,353% dengan kadar air 6,978%. Hasil nilai IC50 uji ABTS sebesar 22,052±0,157 μg/mL tergolong antioksidan sangat kuat. Hasil uji anti-tirosinase menunjukkan aktivitas anti-tirosinase kuat dengan nilai IC50 sebesar 76,598±0,749¼g/mL. Dapat disimpulkan, ekstrak etanol 70% daun belimbing wuluh memiliki aktivitas antioksidan yang sangat kuat dan anti-tirosinase yang kuat.

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Humans need antioxidants to prevent oxidative stress which can cause skin function disorders which is hyperpigmentation. This case is related to enzyme tyrosinase activity which contributes in the production of melanin pigment, so tyrosinase enzyme inhibition is needed to maintain skin brightness. Wuluh starfruit (Averrhoa bilimbi L.) which belongs to the Oxalidaceae family, is one of the plants used as traditional medicine. Wuluh starfruit leaves have been proven to be a source of antioxidants and anti-tyrosinase. This research aimed to determine the identification of fragments and specific tissues of simplicia, percentage yield, percentage water content, antioxidant activity, and anti-tyrosinase activity. Microscopic was carried out using a light microscope. Wuluh starfruit was extracted by maceration with 70% ethanol solvent. Antioxidant activity testing using ABTS method with ascorbic acid standard and inhibition of tyrosinase enzyme derived from fungus Agaricus bisporus species with kojic acid standard and L-DOPA substrate, were analyzed using a microplate reader. Microscopic observations showed the presence of cover hair, upper epidermis with slightly curved walls, lower epidermis with curved walls with stomata and cover hair, parasitic type stomata, leaf veins, and ladder-like wood vessels. The yield obtained from the maceration extraction method was 21,353% with a water content 6,978%. The IC50 value of ABTS test was 22,052±0,157 μg/mL, classified as a very strong antioxidant. The anti-tyrosinase test results showed strong anti-tyrosinase activity with an IC50 value of 76,598±0,749¼g/mL. It can be concluded that the 70% ethanol extract of wuluh starfruit leaves has very strong antioxidant and strong anti-tyrosinase."

"Architectural stress is the inability of a system design to respond to new market demands. It is an important yet often concealed issue in high tech systems. In From scientific instrument to industrial machine, we look at the phenomenon of architectural stress in embedded systems in the context of a transmission electron microscope system built by FEI Company. Traditionally, transmission electron microscopes are manually operated scientific instruments, but they also have enormous potential for use in industrial applications. However, this new market has quite different characteristics. There are strong demands for cost-effective analysis, accurate and precise measurements, and ease-of-use. These demands can be translated into new system qualities, e.g. reliability, predictability and high throughput, as well as new functions, e.g. automation of electron microscopic analyses, automated focusing and positioning functions.From scientific instrument to industrial machine takes a pragmatic approach to the problem of architectural stress. In particular, it describes the outcomes of the Condor project, a joint endeavour by a consortium of industrial and academic partners. In this collaboration an integrated approach was essential to successfully combine various scientific results and show the first steps towards a new direction. System modelling and prototyping were the key techniques to develop better understanding and innovative solutions to the problems associated with architectural stress."

"Kondensasi kromosom memainkan peran penting dalam pembelahan mitosis. Ion Ca2+ diketahui berperan penting dalam proses kondensasi kromosom. Sejauh ini, studi tentang peran Ca2+ dalam kromosom sel hewan telah dilaporkan melalui penggunaan 1,2-bis (2-aminophenoxyethane-N,N,N′,N-tetraacetic acid) (BAPTA) dan Ethylenediamine-tetraacetic acid (EDTA) sebagai agen pengkelat ion Ca2+. Namun, penelitian tentang peran Ca2+ pada kromosom tanaman masih sangat terbatas. Penelitian ini dilakukan untuk mengetahui pengaruh Ca2+ terhadap kromosom gandum (Triticum aestivum) dengan pemberian 1mM BAPTA sebagai agen pengkelat ion Ca2+, 1mM EDTA sebagai agen pengkelat kation divalen umum, dan phosphate buffered saline (PBS) sebagai kontrol menggunakan mikroskop cahaya. Preparasi kromosom dilakukan dengan cara akar gandum dipotong dan diberi perlakuan colchicine sebelum dilarutkan dalam 2% Paraformaldehyde (PFA). Kemudian diinkubasi dengan 2,5% selulase dan 2,5% enzim pectoliase pada suhu 37℃ selama 1 jam. Sampel kemudian disaring dan disentrifugasi untuk memperoleh sampel yang mengandung kromosom. Sampel kemudian diberi perlakuan dengan 1 mM BAPTA, 1 mM EDTA, dan PBS, dan diwarnai dengan Aceto orcein. Kromosom kemudian diamati di bawah mikroskop cahaya. Struktur dan kepadatan warna kromosom, serta panjang, lebar dan luas kromosom diamati dan diukur. Hasil pengamatan kualitatif menunjukkan bahwa struktur kromosom pada kontrol lebih rapat dan pendek sedangkan kromosom yang diberi perlakuan 1 mM BAPTA dan 1 mM EDTA mengalami dekondensasi, melebar, dan berwarna pucat. Hasil pengukuran kuantitatif menunjukkan bahwa kromosom Kontrol, BAPTA, dan EDTA masing-masing memiliki panjang 10.763 m, 14.845 m, 17.154 m, lebar 1.570 m, 1.637 m, 1.723 m, dan luas 18.172 m, 24.644 m, 29.687 M. Hasil uji statistik menunjukkan bahwa pengaruh BAPTA dan EDTA terhadap panjang dan luas kromosom berbeda nyata (α < 0,05). Hal ini membuktikan bahwa Ca2+ memiliki peran penting dalam menjaga struktur kromosom gandum.

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Chromosomal condensation plays an important role in the mitotic division. Ca2+ ions are known to play an important role in the chromosome condensation process. So far, studies on the role of Ca2+ in animal cell chromosomes have been reported using 1,2-bis (2-amino phenoxy ethane N, N, N′, N-tetraacetic acid) (BAPTA) and Ethylene diamine tetraacetic acid (EDTA) as Ca2+ ions chelating agents. However, research on the role of Ca2+ on plant chromosomes is still very limited. This study was conducted to determine the effect of Ca2+ on wheat chromosomes (Triticum aestivum) by administering 1mM BAPTA as a Ca2+ ion chelating agent, 1 mM EDTA as a general divalent cation chelating agent, and phosphate-buffered saline (PBS) as a control using a light microscope. For chromosome preparation, the root tips of wheat were cut and pretreated with colchicine before being dissolved in 2% Paraformaldehyde (PFA). The roots were then incubated with 2.5% cellulase and 2.5% pectoliase enzyme at 37℃ for 1hour. The sample is then filtered and centrifuged to obtain a sample containing chromosomes. Samples were then treated with 1 mM BAPTA, 1 mM EDTA, and PBS and stained with Aceto orcein. Chromosomes were then observed under a light microscope. The structure and color density of the chromosomes were observed. The length, width, and area of the chromosomes were also measured. The qualitative observations showed that the chromosome structure in control was denser and shorter while the chromosomes treated with 1 mM BAPTA and 1 mM EDTA were decondensed, widened, and had pale color. The quantitative measurement showed that length, width, and area of chromosomes for in control, BAPTA, and EDTA were 10.763 m, 14.845 m, 17.154 m; 1.570 m, 1.637 m, 1.723 m; and 18.172 m, 24.644 m, 29.687 M respectively. The statistical results showed that the effect of BAPTA and EDTA on the length and area of chromosomes were significantly different (α < 0.05). This result proves that Ca2+ has a vital role in maintaining the chromosomal structure of wheat."

"Paduan TiNi merupakan paduan ingat bentuk yang dicirikan oleh adanya transformasi fasa reversibel. Dalam penelitian ini dilakukan pengamatan karakteristik presipitat TiNi3 sebagai akibat perlakuan panas penuaan pada paduan Ti-50.04%at.Ni, dengan tujuan untuk dapat mempelajari perilaku presipitat TiNi^ dan pengaruhnya terhadap temperatur transformasi fasa. Pengamatan struktur presipitat dilakukan dengan menggunakan metoda mikroskop elektron transmisi TEM dan temperatur transformasi diamati dengan menggunakan metoda resistivitas \istrik four point probe. Hasil pengamatan menunjukan bahwa presipitat TiNii tumbuh membesar mengikuti penambalian waktu penuaan dengan orientasi pertumbuhannya adalah ....- Pertumbuhan presipitat tersebut tidak menimbulkan perubahan yang signifikan terhadap temperatur transformasi.

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TiNi alloy represents the shape memory alloy which is characterized by reversible phase transformation. In this investigation observation of characteristic TiNi? precipitation of a Ti-50.04%at.Ni alloy affected of aging treatment was carried out. The research was intended to study the influence of TiNi3 precipitate against the phase transformation temperature. The structure precipitate was observed by transmission electron microscope (TEM) and the transformation temperatures measured by four-point probe electrical resistant method. Experimental results showed that TiNi:, precipitates grow up with aging time increased- The orientation of precipitate growth relatively to matrix was found lying on ..... This precipitate growth did not significantly affect the transformation temperature."

"ABSTRAKScaffold membran kitosan dan kitosan-RGD cangkang kepiting diproduksi oleh BATAN, untuk rekayasa jaringan pada rongga mulut. Sifat arsitektural kedua scaffold belum diteliti. Tujuan: Meneliti sifat arsitektural scaffold membran kitosan dan kitosan-RGD cangkang kepiting. Metode: Jumlah, ukuran, jarak antar pori dan porusitas dengan uji SEM dan analisis ImageJ. Daya serap dengan Swelling test. Hasil: Scaffold kitosan dan kitosan-RGD memiliki 225 dan 237 buah pori, berukuran 176.4mm dan 178.3mm, porusitas sebesar 12.8 dan 12.9 , jarak antar pori sebesar 94.7mm dan 93.3mm, serta daya serap sebesar 10.5mgH2O/mgScaffold dan 19.2mgH2O/mgScaffold. Kesimpulan: Sifat arsitektural scaffold membran kitosan RGD cangkang kepiting cenderung lebih baik.

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ABSTRAKIntroduction Crab Shell Chitosan and Chitosan RGD membrane Scaffolds have been made by BATAN, for tissue engineering in oral cavity. Architectural properties of both scaffolds have never been analyzed. Purpose To analyze the architectural properties of both scaffolds. Methods Pore amount, pore size, interpore distance and porosity using SEM test with ImageJ analysis. Water absorption using swelling test. Results Chitosan and Chitosan RGD scaffolds have 225 and 237 pores, 176.4mm and 178.3mm sized pore, porosity of 12.8 and 12.9 , interpore distance of 94.7mm and 93.3mm, with water absorption of 10.5mgH2O mgScaffold dan 19.2mgH2O mgScaffold. Conclusions Crab shell chitosan RGD membrane scaffold has better architectural properties. "

"The book aims to describe the microscopic characterization of the soft matter in the light of new advances acquired in the science of microscopy techniques like AFM, SEM, TEM etc. It does not focus on the traditional information on the microscopy methods as well as systems already present in different books, but intends to answer more fundamental questions associated with commercially important systems by using new advances in microscopy. The contents of the book also reflect this as the chapters are not based on describing only material systems, but are based on the answering the problems or questions arising in their characterization. "