Judul: Efficacy of pelawan leaf infusion (Tristaniopsis merguensis) as  an antidiarrheal in mice (Mus musculus)
Abstrak: Pelawan merah (Tristaniopsis merguensis) merupakan tanaman yang banyak ditemukan di pulau Bangka. Bagian dari tanaman pelawan seperti akar, batang, daunnya banyak dimanfaatkan oleh masyarakat secara turun-temurun sebagai bahan obat untuk berbagai penyakit, salah satunya adalah diare. Daun pelawan merah mengandung metabolit sekunder seperti alkaloid, tanin, dan saponin yang dikenal sebagai zat aktif yang berkhasiat sebagai antidiare. Penelitian ini bertujuan untuk mendapatkan informasi dan data ilmiah mengenai efektivitas antidiare dari infusa daun pelawan merah (Tristaniopsis merguensis) dengan menggunakan metode proteksi intestinal dan transit intestinal. Penelitian ini juga dilakukan untuk menentukan konsentrasi efektif yang memberikan efek antidiare terbaik pada mencit. Penelitian ini menggunakan 25 ekor mencit yang dibagi menjadi lima kelompok yaitu kontrol negatif, kontrol positif, dan tiga kelompok perlakuan yang diberi infusa daun pelawan merah dengan konsentrasi 50%, 75%, dan 100% secara oral. Parameter yang diamati pada metode proteksi intestinal yaitu frekuensi dan konsistensi feses. Parameter yang diamati pada metode transit intestinal yaitu rasio panjang lintasan penanda. Penelitian ini menunjukkan kelompok perlakuan konsentrasi 75% dan 100% memiliki efek antidiare pada kedua metode uji. Efek antidiare terbaik ditunjukkan pada kelompok perlakuan konsentrasi 100% pada kedua metode uji., Pelawan (Tristaniopsis merguensis) is a plant that can be found in the island of Bangka. The parts of pelawan plant, such as the roots, stems, and leaves have been used by the community for generations as medicinal ingredients for various diseases, one of which is diarrhea. Pelawan leaves (Tristaniopsis merguensis) contain secondary metabolites such as steroids, saponins, quinones, and tannins which are known as active substances that are efficacious as anti-diarrhea. This study aims to obtain information and scientific data regarding the antidiarrheal effectiveness of pelawan leaf infusion using intestinal protection and intestinal transit methods. This research was also conducted to determine the effective concentration that give the best anti-diarrheal effect in mice. This study used 25 mice which were divided into five groups: negative control, positive control, and three treatment groups which were given pelawan leaf infusion with concentrations of 50%, 75%, and 100% orally. The observed parameters in the intestinal protection method were the frequency and consistency of the stool. The parameter observed in the intestinal transit method was the ratio of the marker path length. This study showed that the treatment group with a concentration of 75% and 100% have an antidiarrheal effect in both test methods. The best antidiarrheal effect was shown by100% concentration treatment group in both test methods.
Keyword: anti-diarrhea, pelawan, infusion, herbal

Judul: Effectiveness of Gambier Extract Infusion (Uncaria gambir Roxb) as Antidiarrhea in Mice (Mus musculus)
Abstrak: Getah gambir sudah banyak dimanfaatkan oleh masyarakat untuk mengatasi berbagai penyakit, salah satunya adalah diare. Penelitian ini bertujuan untuk mengetahui efektivitas getah gambir sebagai antidiare dengan menggunakan metode proteksi intestinal yang dilihat dari parameter frekuensi, konsistensi, dan durasi. Penelitian ini juga bertujuan menentukan konsentrasi yang paling efektif dalam memberikan efek antidiare pada mencit dan mengetahui metabolit sekunder yang terkandung dalam getah gambir dengan uji fitokimia. Hewan coba dalam penelitian ini menggunakan mencit sebanyak 30 ekor dengan dibagi menjadi 5 kelompok. Kelompok perlakuan terdiri atas kelompok kontrol negatif, kontrol positif, dan tiga kelompok perlakuan yang diberi infusa getah gambir dengan konsentrasi 25%, 50%, dan 100% secara oral. Parameter yang dinilai dalam metode proteksi intestinal adalah frekuensi defekasi, konsistensi feses, dan durasi diare. Hasil penelitian menunjukkan getah gambir memiliki metabolit sekunder yang berpotensi sebagai antidiare seperti alkaloid, flavonoid, saponin, dan tanin pada uji fitokimia. Hasil dari metode proteksi intestinal menunjukkan kelompok perlakuan infusa getah gambir konsentrasi 25%, 50%, dan 100% terbukti mampu menurunkan frekuensi defekasi, memperbaiki konsistensi, dan mempersingkat waktu diare. Kelompok konsentrasi 25% dan 50% menunjukkan aktivitas antidiare lebih baik daripada konsentrasi 100%., Gambier extract has been widely used by the community to treat various diseases, one of which is diarrhea. This study aims to determine the effectiveness of gambier sap as an antidiarrhea using intestinal protection methods as seen from the parameters of frequency, consistency and duration. This research also aims to determine the most effective concentration in providing antidiarrheal effects in mice and determine the secondary metabolites contained in gambier sap using phytochemical tests. The experimental animals in this study used 30 mice divided into 5 groups. The treatment groups consisted of a negative control group, a positive control, and three treatment groups that were given gambier extract infusion at concentrations of 25%, 50%, and 100% orally. The parameters assessed in the intestinal protection method are defecation frequency, fecal consistency, and duration of diarrhea. The research results showed that gambier extract has secondary metabolites that have the potential to act as antidiarrhea such as alkaloids, flavonoids, saponins and tannins in phytochemical tests. The results of the intestinal protection method showed that the gambier extract infusion treatment group with concentrations of 25%, 50%, and 100% was proven to be able to reduce the frequency of defecation, improve consistency, and shorten the time of diarrhea. The 25% and 50% concentration groups exhibited better antidiarrheal activity than the 100% concentration
Keyword: antidiare, infusa, proteksi intestinal, uji fitokimia, Getah gambir

Judul: Bifurkasi Hopf pada Model Siklus Bisnis Kaldor Kalecki tanpa dan dengan Waktu Tunda
Abstrak: Business cycle model is one of dynamical system models in economic. One of the business cycles model is Kaldor-Kalecki model. Kaldor-Kalecki business cycle model that is written in delayed defferential equations, is a business cycle model that involves gross product and capital stock of a company. In this paper Kaldor-Kalecki business cycle model is analyzed using both nondelay and delay in time of capital stock. By Taylor expansion for the time delayed model, an analysis of stability around the fixed points has been done. Furthermore, by using Hopf bifurcation theorem, it can be shown that there exists periodic orbits and limit cycle. In the nondelayed model, changing the parameter of goods market could lead to the occurrence of Hopf bifurcation and the existence of limit cycle. Similarly, for the delayed model, it has been shown that changing the time delay parameter may result in the occurrence of Hopf bifurcation and limit cycle.
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