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"La2Ti2O7 merupakan material ferroelektrik yang memiliki temperatur Curie yang tinggi, sehingga dapat digunakan sebagai sensor yang digunakan pada temperatur tinggi. Beberapa penelitian telah dilakukan untuk mendapatkan sifat material yang optimal, dengan cara subtitusi Ce, Ta, Bi kedalam material La2Ti2O7, dimana subtitusi Bi dapat meningkatkan dielektrik material. Pada penelitian ini, material La2-xBixTi2O7 dengan x = 0.1 dan 0.2 telah berhasil disintesis dengan menggunakan metode Sol-gel. Proses sintesis material menghasilkan pellet (bulk). Uji karakterisasi yang telah dilakukan pada material bulk tersebut adalah, XRD, SEM, EDX, dan Impedansi Spektroskopi. Hasil uji karakterisasi XRD, menunjukan sampel single phase, dengan struktur monoklinik dan space group P21. Hasil uji SEM dan EDX, menunjukan adanya puncak dari semua elemen prekursor dan juga ukuran rata rata grain dari sampel menurun dengan penambahan jumlah Bi. Selain itu, hasil SEM juga menunjukan bahwa ukuran dan distribusi dari morfologi kedua sampel tidak merata. Karakterisasi sifat listrik dilakukan pada rentang frekuensi 500 Hz hingga 1 MHz, dan dengan rentang temperatur 75˚C hingga 175˚C. Hasil Impedansi spektroskopi menunjukan diameter semisirkular yang semakin menurun seiring meningkatnya temperatur. Hal tersebut mengindikasikan bahwa kedua material memiliki trend sifat semikonduktor. Dielektrik material juga meningkat seiring meningkatnya subtitusi Bi. Hal tersebut disebabkan karena tinggi nya polarisasi ion Bi3+ dengan pasangan elektron bebas. Selain itu, konduktivitas dc juga meningkat seiring meningkatnya jumlah subtitusi Bi.

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La2Ti2O7 is a ferroelectric material that has a high Curie temperature, so it can be used as a sensor that is used at high temperatures. Several studies have been carried out to obtain optimal material properties, by substituting Ce, Ta, Bi into La2Ti2O7 material, where Bi substitution can increase the dielectric. In this research, La2-xBixTi2O7 material with x = 0.1 and 0.2 has been successfully synthesized using the sol-gel method. The material synthesis process produces pellet (bulk). Characterization have been carried out on these bulk materials are XRD, SEM, EDX, and Impedance Spectroscopy. The results of the XRD characterization shows a single phase, with a monoclinic structure and space group P 1 21 1. The results of the SEM and EDX show that there were peaks of all precursor elements and also that the average grain size of the sample decreased with increasing the amount of Bi. In addition, the SEM results also show that the size and distribution of the morphology of the two samples is uneven. Characterization of electrical properties was carried out in the frequency range of 500 Hz to 1 MHz, and with a temperature range of 75˚C to 175˚C. The results of impedance spectroscopy show that the semicircular diameter decreases with increasing temperature. This indicates that the two materials have a trend of semiconductor properties. The dielectric of the material also increases with increasing Bi substitution. This is due to the high polarization of the Bi3+ ion with a lone pair of electrons. In addition, the dc conductivity also increases with increasing number of Bi substitutions."

"ABSTRAKStunting merupakan kondisi malnutrisi pada anak yaitu tinggi badan menurut usia lebih dari minus 2 simpang baku. Indonesia menempati urutan kelima di dunia. Stunting berkorelasi dengan asupan makanan terutama protein, IGF-1 dan protein pengikat Insulin like Growth Factor Binding Protein IGFBP-3 , dan Zinc Zn . Kualitas protein dinilai dari profil asam amino bebas plasma Plasma Free Amino Acid = PFAA dan kuantitas dinilai dari jumlah asupan protein harian. Beberapa penelitian menemukan kadar IGF-1 dipengaruhi oleh polimorfisme SNP rs5742612, rs35767 dan rs35766. Penelitian ini bertujuan untuk menganalisis peran profil PFAA, IGF-1, IGFBP-3, polimorfisme IGF-1, Insulin, dan Zn pada anak.Penelitian ini merupakan studi comparative cross sectional dilakukan di RS Cipto Mangunkusumo, Lembaga Biomolekular Eijkman, dan Labkesda DKI Jakarta. Subjek penelitian adalah anak usia 1 ndash;3 tahun berasal dari UPTD Puskesmas Jatinegara dibagi menjadi 2 kelompok yaitu 101 anak stunted dan 101 anak nonstunted.Pada penelitian ini didapatkan kadar 8 dari 9 AA esensial, 2 AA esensial kondisional, dan 2 AA nonesensial lebih rendah bermakna kelompok stunted dibandingkan nonstunted. Profil PFAA yaitu jumlah anak di bawah nilai rujukan berbeda bermakna antara kelompok stunted dan nonstunted. Terdapat korelasi 8 AA esensial, 1 AA esensial kondisional, dan 2 AA nonesensial dengan tinggi badan anak. Pada kelompok anak stunted, IGF-1, IGFBP-3, insulin, Zn, energi total dan protein lebih rendah bermakna dari kelompok anak nonstunted. Terdapat korelasi bermakna AA esensial dengan IGF-1 dan IGFBP-3. Polimorfisme rs35766 genotipe AG kodominan memiliki pengaruh terhadap kadar IGF-1 pada kelompok nonstunted. Faktor yang memengaruhi kejadian stunting adalah energi atau protein, IGF-1 yang berinteraksi dengan genotipe kodominan AG, IGFBP-3, dan Zn.Simpulan: PFAA, IGF-1 yang berinteraksi dengan SNP rs35766 genotipe kodominan AG, memiliki pengaruh terhadap kejadian stunting. Perlu penelitian lebih lanjut mengenai pemberian pola makan yang tepat untuk mencegah dan mengatasi anak stunted. Kata kunci: AA esensial, AA nonesensial, IGFBP-3, insulin, PFAA, stunting, Zn

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ABSTRACTStunting is a malnourished condition in children defined by height for age is under minus 2 standard deviation. Indonesia ranked fifth in world for this condition. Stunting mainly corelates with low protein intakes, IGF-1 and its binding protein Insulin-like Growth Factor Binding Protein/IGFBP-3 , and zinc Zn . Plasma free amino acid profile PFAA measures quality of protein intake, whilst its quantity measured by daily protein intake records. Previous studies found IGF-1 level affected by single nucleotide polymorphism SNP on rs5742612, rs35767 and rs35766. This study aims to analyze the role of PFAA, IGF-1, IGFBP-3, and IGF-1 polymorphism, insulin, and Zn in children.This study is a comparative cross-sectional study held in Cipto Mangunkusumo National General Hospital, Eijkman Institute for Molecular Biology, and Jakarta Provincial Public Health Laboratory. Subjects were children age 1 ndash;3 years old from Jatinegara Region Public Health Centre divided into two groups of 101 stunted children and 101 non-stunted children.Eight essential AA levels, 2 conditional essential AAs, 2 nonessential AAs were significantly lower in stunted groups than non-stunted. There was significant difference of profile PFAA below normal range between stunted and non-stunted group. Eight essential amino acids, 1 conditional essential amino acid, and 2 non-essential amino acid correlate with children rsquo;s height. IGF-1, IGFBP-3, insulin, Zn, total energy, and protein were significantly lower in stunted children compare to non-stunted children. Significant correlations found for all essential amino acids with IGF-1 and IGFBP-3. The rs35766 AG codominant polymorphism affects IGF-1 level in non-stunted group. Factors affects stunting condition were total energy or protein intake, IGF-1 that interacts with AG codominant genotype, IGFBP-3, and Zn.Conclusion: PFAA and IGF-1 that interacts with SNP rs35766 AG codominant genotype affect stunting. Further study needed to determine appropriate dietary habit for stunting prevention and treatsment. Keywords: Essential amino acid, IGFBP-3, insulin, non-essential amino acid, plasma free amino acid profile, stunting, zinc"