Judul: Effectiveness of Basil Leaf Extract to Reduce NH3 and H2S Gas Levels of Quail (Coturnix coturnix japonica) Excreta
Abstrak: ABSTRACT This study examine the effect of basil leaf extract on the reduction of ammonia gas (NH3) and hydrogen sulphide gas (H2S) quail excreta (Coturnix coturnix japonica) and their optimal composition. Basil leaf extraction maceration method by soaking simplisia on ethanol 96% with comparison ratio 1:10. Antibacterial activity test used disc diffusion method to determine the activity of antibacterial agents. The antibacterial agent using non-antibiotic paper disc and basil leaf. The inoculum contains 106 mL-1 bacterial cells S.aureus and E.coli are spreads on the MHA media. The diluted extract with DMSO until 200 mg mL-1, 150 mg mL-1, 100 mg mL-1 and 50 mg mL-1. Petri dish was incubated at 37oC for 24 hour. This study used a completely randomized design trial with one factor of basil leaf extract with five treatments with a level of 200 mg mL-1, 150 mg mL-1, 100 mg mL-1, 50 mg mL-1, and one treatment without section. This study repeated all treatments three times. This study indicate that the additional basil leaf extract with a maximum concentration 200 ppm optimal can reduce NH3 and H2S gas levels compared to controls were not given additional extract. Keywords: excreta, basil leaf extract, NH3, H2S
Keyword: ekskreta, ekstrak daun kemangi, NH3, H2S, excreta, basil leaf extract, NH3, H2S

Judul: Application of Moringa Oleifera Leaf Extract and EM-4 in Drinking Water on the Reduction of Ammonia Levels in Laying Quail Excreta
Abstrak: Penelitian ini bertujuan menganalisis efek pemberian ekstrak daun kelor dan EM-4 terhadap penurunan kadar amonia ekskreta puyuh petelur serta hubungan antar peubah yang diamati. Sebanyak 150 ekor puyuh betina dipelihara dalam rancangan acak lengkap (RAL) dengan 3 perlakuan dan 5 ulangan. Perlakuan terdiri dari P0 = Tanpa ekstrak daun kelor dan EM-4 dalam air minum ekor-1 hari-1 (kontrol), P1 = Penambahan 2 ml ekstrak daun kelor dan EM-4 ekor-1 hari-1, P2 = Penambahan 4 ml ekstrak daun kelor dan EM-4 ekor-1 hari-1. Peubah yang diukur meliputi kadar amonia (NH3), protein kasar, nitrogen, kadar air, dan pH ekskreta. Data dianalisis dengan uji ragam (ANOVA) dan uji Duncan bila hasil ANOVA signifikan, serta analisis korelasi Pearson untuk hubungan antar peubah. Hasil menunjukkan bahwa kombinasi ekstrak dan EM-4 tidak berpengaruh signifikan (P>0,05) terhadap kadar amonia (NH3), kadar air, dan pH ekskreta. Kombinasi ini secara signifikan menurunkan (P<0,05) kadar protein kasar dan nitrogen ekskreta pada perlakuan P1. Amonia ekskreta berkorelasi sangat kuat dengan kadar air dan pH ekskreta (r = 0,87 dan r = 0,92). Kadar protein kasar berkorelasi sempurna dengan kadar nitrogen ekskreta (r = 1,00), dan kadar air ekskreta berkorelasi sangat kuat dengan pH ekskreta (r = 0,96)., This study aimed to analyze the effects of providing Moringa leaf extract and EM-4 on the reduction of ammonia levels in layer quail excreta and the relationship between the observed variables. A total of 150 female quails were raised in a completely randomized design (CRD) with 3 treatments and 5 replicates. The treatments were: P0 = Moringa leaf extract and EM-4 in drinking water bird-1 day-1 (control), P1 = Addition of 2 ml of Moringa leaf extract and EM-4 in drinking water bird-1 day-1, and P2 = Addition of 4 ml of Moringa leaf extract and EM-4 in drinking water bird-1 day-1. Variables measured included ammonia (NH3) content, crude protein, nitrogen, water content, and excreta pH. Data were analyzed using analysis of variance (ANOVA) and Duncan's test if ANOVA results were significant, and Pearson correlation analysis for the relationship between variables. Results showed the combination of extract and EM-4 didn’t significantly affect (P>0.05) ammonia (NH3) content, water content, and excreta pH. This combination significantly decreased (P<0.05) crude protein and nitrogen content of excreta in treatment P1. Excreta ammonia was strongly correlated with water content and excreta pH (r = 0.87 and r = 0.92). Crude protein content was perfectly correlated with nitrogen content of excreta (r = 1.00), and water content of excreta was strongly correlated with excreta pH (r = 0.96).
Keyword: moringa leaf extract, Ammonia excreta, EM-4, layer quail

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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