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Kalikuning is one of the areas that has a diversity of flora. Kalikuning's fertile land helps a variety of plants flourish there. Since there are no people living here, a wide variety of unidentified and underexplored plants can be known. Therefore, more research on the plant diversity is required. The research aims to invent, document, and find out the diversity of the understory (shrubs and herbs) in Kalikuning. This research used survey and exploration methods. The researchers documented shrub and herb species. Based on the results, 28 families consist of 65 species of shrubs and herbs. Those species are flora that have specific characteristics.

Synthesis of Zr-ZA catalyst used as catalyst for esterification reaction of glycerol with acetic acid anhydrous has been done. Catalysts are characterized using an infrared spectrophotometer, X-ray diffraction, and measurement of surface acidity, while reaction products are characterized using a gas chromatography-mass spectrometer. Effect of catalyst acidity, reaction time and re-addition of acetic acid anhydrous studied by glycerol conversion and selectivity value of triacetin were yielded. Infra-red spectrophotometer and X-ray diffraction analysis of the catalyst showed that the synthesized catalyst was zirconium zeolite (Zr-ZA), while esterification analysis using a gas chromatography-mass spectrometer showed a triacetin product.

The electronic transition processes of α-mangostin and β-mangostin as dye compounds in DSSC and their ability to transfer electrons to semiconductors have been studied in theory. The research was carried out computationally using the NwChem application. The methods used are Density Functional Theory (DFT) for structure optimization and Time-Dependent DFT (TD-DFT) for electronic transitions. The results showed that the energy of HOMO β-mangostin was lower that it was more stable or easier to form bonds with semiconductors. Likewise, its LUMO energy is lower than α-mangostin that it is easier to inject electrons into the semiconductor. The energy difference of HOMO-LUMO β-mangostin is smaller than α-mangostin. This shows that β-mangostin is more easily excited or more efficient in exciting solar energy to convert it into electricity. This is consistent with the molecular spectra where λmaxβ-mangostin is at a higher wavelength. Orbital analysis shows electron injection of α-mangostin and β-mangostin into the semiconductor via double O atoms in each molecule. The injection is influenced by the bond length, where the bond length of α-mangostin to TiO2 is smaller than that of β-mangostin to TiO2.

Sharks are sea water fishes belong to the class Chondrichthyes, Subclass Elasmobranchii. Sharks are cartilaginous fish that have a different osmoregulation process than any other sea water fish. Cartilaginous fish is the only vertebrate that can maintain urea. This study aims to determine the anatomical and histological structure of the kidney in the anterior, medial and posterior parts of kidney. The study was conducted by observing anatomy of the kidney. Histological preparations were made using the paraffin method. Qualitative descriptive data analysis was done. Research results show that shark kidneys consist of three parts, namely the head kidney, the body kidney, and the tail kidney. Kidney sharks are brownish red with a size of 18 cm long. Histological observations of shark kidney in the head kidney reveals many glomerulus, body kidney reveals many distal and tubule proximal contractile tubules whereas tail kidney reveals stroma that is rarely found in vertebrate kidney.

Echinoderms are one of marine invertebrate animals that have an important role, as a recycle of nutrients in the functioning of ecosystems. Echinoderms usually appear in the intertidal zone of the coast. The existence of echinoderms in the intertidal zone is affected by external and internal factors. This study aims to determine the level of abundance and diversity of Echinoderms in the intertidal zone in the Krakal and Drini coastal areas, Gunung Kidul, Yogyakarta. Data were collected using transect method. The main transect along 50 meters was divided into 5 sampling points, and the distance between sampling points was 10 meters. After that, each point was taken for 3 observation plots with an area of 1x1 meters and the distance between plots is 5 meters. The results showed that, the diversity index on the krakal coast had a higher value (0.139) when compared to the Drini coast (0.129). Calculation of echinonderm abundance index shows that the Drini beach location has a high abundance value when compared to the abundance value at the Krakal beach loc ation. The parameter measurement results can be seen that both the pH and temperature parameters on both the Krakal and Drini coast have values that correspond to the optimum parameter in the waters.