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"ABSTRACTCurrent electronics technology still relies on semiconductors for several purposes. The special property that distinguishes a semiconductor from another material is band gap energy inside of which the Fermi energy is located. Most conventional semiconductors such as Ge, Si, or GaAs may be classified into none or weakly correlated systems in which electron electron e e interactions do not play any significant role, where the band gaps insensitive to temperature change. Meanwhile, in semiconductors containing transition metal elements having d orbitals in their valence and or conduction band s , which we consider as strongly correlated semiconductors, e e interactions may play a more significant role. We hypothesize that such kind of semiconductors would have band structures, including their band gaps, being rather sensitive to temperature change due to e e interactions. We propose to explore this hypothesis theoretically by modeling the semiconductor band structure through Tight Binding Approximation with the GW method numerically in the Matsubara frequency domain. At the end, we use Pad approximant to obtain the self energy defined in the real frequency domain. Using this self energy we can calculate and analyze the Density Of States DOS at various temperatures, by giving the certain range of bare interaction line V. Our research results the correlation effects become stronger as we decrease the temperature. In short ranged interaction confirms that the semiconductor band gap increases and chemical potential shifts to a higher energy. Whereas with long ranged interaction shows that the range of two bands semiconductor becomes farther apart as compared to the bare DOS.

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ABSTRACTTeknologi elektronik saat ini masih mengandalkan material semikonduktor untuk berbagai kebutuhan. Properti yang membedakan semikonduktor dari material lain adalah celah pita energi di mana energi Fermi berada di dalamnya. Umumnya semikonduktor seperti Ge, Si, atau GaAs dapat diklasifikasikan ke dalam sistem non terkorelasi / terkorelasi lemah di mana interaksi elektron-elektron e-e tidak memiliki peran penting, sehingga pita energi nya mungkin tidak sensitif terhadap perubahan suhu. Sedangkan semikonduktor yang mengandung unsur logam transisi dan orbital d dalam pita valensi dan / atau pita konduksi dianggap sebagai semikonduktor terkorelasi kuat, dimana interaksi e-e memainkan peran lebih signifikan. Kami berhipotesis bahwa jenis semikonduktor ini akan memiliki lebar celah pita yang agak sensitif terhadap perubahan suhu. Kami mengeksplorasi hipotesis ini secara teoritis dengan pemodelan struktur pita semikonduktor melalui pendekatan Tight-Binding, kemudian menerapkan interaksi e-e dalam metode GW secara numerik dalam domain frekuensi Matsubara. Setelah itu kami menggunakan Pad approximant untuk memperoleh self-energy yang didefinisikan dalam domain frekuensi riil. Dengan menggunakan self-energy ini kita dapat menghitung dan menganalisis Density Of States DOS seiring dengan bertambahnya suhu, dengan memberikan variasi rentang dari bare interaction line V . Penelitian kami membuktikan bahwa efek-efek korelasi menjadi lebih kuat seiring menurunnya suhu. Untuk variasi interaksi rentang pendek, pita energi melebar dan potensial kimia semakin bergeser ke tingkat energi lebih tinggi. Sedangkan pada variasi interaksi rentang panjang, jarak antara dua pita energi semikonduktor semakin melebar jika dibandingkan dengan DOS murni."

"Latar Belakang: Luka kaki diabetes merupakan masalah paling umum pada penyandang DM. Tanpa perawatan yang tepat, luka dapat mengakibatkan infeksi, amputasi atau kematian. Tingkat mortalitas 3 tahun setelah amputasi akibat luka diabetes tidak banyak berubah dalam 30 tahun terakhir, walaupun dengan kemajuan medis dan pembedahan. LLLT merupakan salah satu terapi adjuvan yang dapat mempercepat penyembuhan luka kronis seperti luka diabetes, namun belum ada pedoman yang pasti mengenai dosis LLLT. Hingga saat ini, belum ada penelitian di Indonesia yang membandingkan densitas energi terhadap penyembuhan luka diabetes. Tujuan: Mengetahui perbedaan efektivitas penyembuhan luka kaki diabetes dengan kedua densitas energi. Metode: Penelitian ini adalah studi eksperimental dengan 28 subjek dengan luka kaki diabetes yang dirandomisasi. Pengambilan sampel dilakukan secara konsekutif. Kelompok A mendapat perawatan luka rutin dan LLLT 5 J/cm2. Kelompok B mendapat perawatan luka rutin dan LLLT 10 J/cm2. Intervensi dilakukan selama 4 minggu, dengan frekuensi 2x/minggu. Penilaian yang diambil adalah selisih ukuran luka dan kecepatan penyembuhan luka setiap minggu.Hasil: Selisih ukuran luka setelah intervensi 4 minggu antara kelompok A dan kelompok B adalah 4.15 mm2 dan 7.5 mm2 (p=0.178). Total kecepatan pemulihan luka pada kelompok A dan kelompok B adalah 4.15 (-10-34.5) mm2/4 minggu and 7.5 (-2.8-34) mm2/4 minggu (p=0.168). Kesimpulan: Pemberian LLLT dengan 5 J/cm2 maupun 10 J/cm2 tidak memberikan efek yang berbeda bermakna secara statistik terhadap penyembuhan luka kaki diabetes.

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Background: Diabetic foot ulcer is one of the most common complications in DM patients. Without proper management, the ulcer may lead to infection, amputation or even death. Three-year mortality rate after the amputation due to diabetic ulcer has not changed much for the last thirty years, despite the advancement in medical and surgical aspects. LLLT is one of the adjuvant therapies that are used to enhance healing of chronic wound, such as diabetic ulcer, however there is no established guideline for LLLT dosage. Thus far, there has been no research conducted in Indonesia comparing the energy density of LLLT on diabetic foot ulcer healing. Aim: To compare the effectiveness between two energy densities in diabetic foot ulcer healing. Method: This research is an experimental study on 28 randomized subjects with diabetic foot ulcer. Sampling was done consecutively. Group A received standard treatment of ulcer and LLLT 5 J/cm2. Group B received standard treatment of ulcer and LLLT 10 J/cm2. Intervention was carried out twice a week for 4 weeks. The outcomes are wound size and healing rate every week. Result: The difference of wound size between group A and group B after 4 weeks were 4.15 mm2 and 7.5 mm2 (p=0.178). The healing rate of group A and group B were 4.15 (-10-34.5) mm2/4 weeks and 7.5 (-2.8-34) mm2/4 weeks (p=0.168). Conclusion: There was no statistically significant difference between group receiving LLLT 5 J/cm2 or 10 J/cm2 in diabetic foot ulcer healing."

"Thermal conversion of woody biomass to fuel has been intensified in recent decades due to the depletion of fossil fuels, greenhouse effect and high energy demand worldwide. Screening the potential feedstock is being considered as one of the alternatives to identifying the most suitable biomass resources prior to being converted into renewable energy in the form of solid fuels, such as charcoal and briquettes. Generally, high calorific value (CV) indicates high potential of feedstock for briquettes, torrefied wood and coal generation. In this study, CV was characterized using a bomb calorimeter that was based on 3 different ranges of moisture content (MC) that are ? 25%, 20%?25% and ? 20% for two tropical tree species, namely Azadirachta excelsa (Sentang) and Endospermum malaccense (Sesenduk), respectively. This standard method for the characterization process was considered to determine the CV. Average CV for both samples ranged between 16?17 MJ/kg. The highest CV was 17.3490 MJ/kg and 17.1273 MJ/kg for Sesenduk and Sentang, respectively and calorific values were obtained at MC less than 20%. The experimental study demonstrated that the decreasing value of MC has increased the CV because of the high value of oxygen-to-carbon (O/C) ratio in the wood; additionally, the energy density of the wood sample was also improved when CV increased. Both of these species were proved to contain the potential of being feedstock as wood fuel resources, since they carry standard CVs, obtain fast growth with suitable conditions in Malaysia and are grown at very low cost of production for plantations, fertilizer, pesticides, labor, transportation and handling."