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Cellulose is a natural biopolymer extensively utilized in biomedical applications. This study aims to develop a novel cellulose nanofiber (CNF) from areca nut shell, reinforced with cerium oxide nanoparticles (CeO2NPs). XRD analysis confirms successful synthesis of crystalline CNF and CeO2NPs with the cubic structure, strengthened by Le-Bail refinement. Following FESEM and EDX analysis, spherical CeO2NPs nanoparticles with sizes ranging between 18 and 32 nm were formed and finely distributed on the CNF surface. The prepared CNF/CeO2NPs samples exhibited high antibacterial activity against S.aureus and E.coli. These findings highlight an innovative approach of materials with environmentally friendly for advanced biomedical applications.

This work successfully synthesized single-phase Aurivillius Bi4Ti2.75(FeNb)0.125O12 using a molten salt method and the natural precursor of Fe3+ ions extracted from Padang Beach sand. The study extensively examined the phase formation, crystal structure, grain morphology, and physical properties. X-ray diffraction (XRD) analysis combined with the Rietveld refinement technique confirms that Bi4Ti2.75(FeNb)0.125O12 adopts a B2cb orthorhombic structure. The refined atomic positions reveal that Bi3+ ions are located in the A-site within both the bismuth and perovskite layers, while the B-sites within the perovskite layers are primarily occupied by Ti4+/Nb5+/Fe3+ ions. The lower distortion of the inner B(1)O6 octahedra suggests the preference of Fe-rich clusters. The magnetization hysteresis suggests that the Bi4Ti2.75(FeNb)0.125O12 phase exhibits a weak antiferromagnetic state arising from the local short-range Fe–O–Fe antiferromagnetic ordering in the inner B(1)O6 octahedra. The electrical measurements reveal that the existence of ferroelectric ordering at room temperature comes from the structural distortion and the off-center ionic displacement. The energy storage capacity of 10.15 mJ/cm3 and efficiency (η) of 50.2% were obtained in ceramic sample under an electric field of 70 kV/cm at room temperature.

Nanoparticles of cerium oxide have been synthesized by green precipitation method by the presence of Moringa oleifera leaf extract with a short reaction time of 5 h. Base on XRD analysis confirmed structure crystal of cerium oxide the formation was a cubic. CeO2NPs were discovered to have a spherical shape and an average size of 17 nm, as shown in the TEM image. The formation of CeO2NPs was furtherly proven by EDX measurement in the presence of high-intensity peaks referred to Ce and O, with no impurities. The result after FTIR analysis of the nanoparticles demonstrates the appearance of Ce–O stretching, as well as the O–N–O bending disappearance. Based on the DRS UV–Vis analysis result, the band gap energy of CeO2NPs was found to be 18% lower than the bulky size. The synthesized CeO2NPs exhibit a high antimicrobial activity in the range of 15–31 mm zone inhibition.

Self-confidence is the ability of students to build positive energy that is useful for completing tasks or working optimally. However, the reality is that some students feel unsure of their abilities which results in them not doing given assignments. Students also tend to give up easily and are lazy when they are given problems that are more difficult than usual, the reason being they think they are unable to solve them. God calls every Christian teacher to develop a learning community where students feel cared for and able to use their abilities in the learning process. Therefore, the purpose of this paper is to look at the role of the teacher in developing students’ confidence in mathematics. The teacher's role is to pay attention to the factors that cause low student confidence and then to design learning strategies that suits students' needs. Teachers can develop self-concepts, motivation, encouragement, practice exercises, reviews, and assessments that enable students to be more confident in their ability to glorify God. Other suggestions for teachers are to provide questionnaires or interviews in advance to collect data on low student confidence rates so that teachers can determine the right strategy according to student needs. BAHASA INDONESIA ABSTRACT: Kepercayaan diri atau keyakinan akan kemampuan siswa dapat membangun energi positif yang berguna untuk menyelesaikan tugas ataupun pekerjaan secara maksimal. Akan tetapi kenyataan yang didapatkan di kelas yaitu beberapa siswa merasa tidak yakin akan kemampuannya yang mengakibatkan siswa tidak mengerjakan tugas yang diberikan. Siswa juga cenderung untuk mudah menyerah dan malas mencoba ketika diberikan soal yang lebih sulit daripada biasanya, alasannya karena mereka berpikir tidak mampu untuk menyelesaikannya. Tuhan memanggil setiap guru Kristen untuk mampu mengembangkan kelas menjadi sebuah komunitas untuk belajar agar siswa merasa berada dalam lingkungan yang peduli terhadapnya sehingga siswa mampu untuk menggunakan kemampuan yang dimiliki dalam proses pembelajaran. Oleh karena itu, tujuan penulisan makalah ini yaitu melihat peran guru dalam menumbuhkembangkan kepercayaan diri siswa dalam pelajaran matematika. Peran guru dalam menumbuhkembangkan kepercayaan diri siswa dalam pembelajaran yaitu dengan memperhatikan faktor penyebab rendahnya kepercayaan diri siswa dan merancang pembelajaran yang sesuai dengan kebutuhan siswa. Guru dapat menumbuhkan konsep diri, memberikan motivasi serta dorongan, latihan soal, review dan evaluasi kepada siswa untuk lebih yakin akan kemampuannya untuk memuliakan Tuhan. Saran bagi guru lain yaitu sebaiknya memberikan kuesioner ataupun wawancara terlebih dahulu untuk mengumpulkan data rendahnya kepercayaan diri siswa sehingga guru dapat menentukan strategi yang tepat sesuai kebutuhan siswa.

This paper aims at assessing corporate governance by the instrumentality of ratings for a sample of 115 companies listed on the IDX during 2012-2016 in 575 cases. The novelty of this study emphasis by the corporate governance ratings developed for the companies listed on the IDX by using multidimensional data analysis techniques, namely Moderating Analysis Regression (MRA), and Earnings Quality index as moderation variable. The utility of current research underlines by the information related to CG ratings towards investors globally, thus supports the investment decision making.

Clams have a planktonic period which is sensitive to metal pollutants in the waters. The natural concentration of cadmium (Cd) is relatively low in marine waters, but may increase with increasing anthropogenic activity on land that may be lethal to organisms, especially in the sensitive larval stages. The purpose of this study was to analyze the values of 24h-LC50, NOEC (No Observed Effect Concentration), LOEC (Lowest Observed Effect Concentration) and MATC (Maximum Acceptable Toxicant Concentration) along with the impact of acute Cd toxicity on mortality and morphological changes of Tridacna squamosa veliger. The toxicity test used was an acute toxicity test with a static method (4 replications). Acute toxicity tests were performed on veliger phase larvae with short-term exposure (24 hours) on various Cd concentrations ie., 0.1 mg/L, 1 mg/L, 2.5 mg/L, 5 mg/L and 10 mg/L . The 24h-LC50 value was calculated using the Trimmed Spearman-Karber application version 4.1 and the LOEC and NOEC values were analyzed using the Dunnet test. Results showed that the 24h-LC50 value of Cd applied to Tridacna squamosa veliger was 2.12 mg/L, whereas the NOEC, LOEC and MATC values were 1 mg/L, 2.5 mg/L, 1.581 mg/L respectively. Mortalities were observed with increasing Cd concentrations. It was also shown a decreasing number of zooxanthellae, damaged in mantle tissue and shells, changes in shell color, released of mantle tissue from the shell with increasing Cd concentrations.

Marine debris is defined as material that is solid, persistent, manufactured or processed, and deliberately or not-deliberately left in the marine environment. Marine debris comes in many shapes and forms, ranging in size from microscopic microplastics to large vessels. Marine debris is a big and growing global problem, pose threats to marine life sustainability. Plastic is a major component of marine debris, and single use packaging accounts for an increasing part of the global marine debris load. Research on marine debris were conducted on coastal areas and Small Island of South Sulawesi destined for local tourism, i.e. Karama beach, Bodia beach and Mandi beach (Galesong, Takalar District), Tanjung Bayang beach, Akkarena beach and Lae-lae island/also known as Bob beach (Makassar City). This research was aimed at identifying marine debris according to its types, size and mass. Debris were collected in a 25 x 60 m transect with direction 30 m towards land and waters, respectively, with 3 replication transects at every location, whilst collections of debris were conducted during low and high tides. Current (direction and speed) and waves (incoming direction and height) were also measured as supporting parameters. Surrounding sampling location characteristics were also recorded. Result showed that Karama beach is found with highest total marine debris mass in Takalar (36.44 kg), whilst in Makassar the Lae-lae island was found to be the highest with debris mass (43.22 kg). Plastic were predominant debris at all sampling locations with percentages of 62.7 – 86.6%. Lastly, the predominant size was macro-debris (25-100 cm).

Culture of ornamental corals applying transplantation technique was aimed to know the successful of this transplantation technique in the ornamental coral culture based on its growth and survival rate of various coral fragments. The location of the medium settlement was in the western side of the waters of Tonyaman Village, Binuang Subdistrict, Polewali Mandar Regency with 3-4 meter depth during low tide. One of coral species i.e. Acropora sp with 48 fragments was put on 4 transplantation tables. During the experiment, cleaning of fungi and biofouling at the transplant tables and the culture tables. Measurements of the absolute growth and survival rate were done at the 21st day using calliphers and numbers of dead and live fragments were counted directly. Coral transplantation workshop for ornamental coral culture was attended by 4 fisherman groups with total 23 participants. This event was understood by the training participants from the seed selection to the monitoring. Number of coral fragment cultured was 48 fragments obtained from one of stony corals (Scleractania), i.e. Acropora sp. The range of survival rate that has been cultured for 21 days was adequately high i.e. 91.7 – 100 %. The highest survival rate was observed at the transplant table B, i.e. 100%, whereas, the table A, C, and D were 91.7 %. Average absolute growth of the coral Acropora sp cultured during this study were ranged from 4.2 – 4.9 mm/month. Aaverage absolute growth was found at table transplant B and C, while the lowest value was observed at the transplant table D. Keywords: cultivation, ornamental coral, transplantation technique, Tonyaman

The purpose of this study was to analyze the succesfullnes use of two coral reef transplantation methods in the rehabilitation of coral reefs damaged by the phenomenon of bleaching in 2016 at the waters of Liukangloe Island, Bulukumba, South Sulawesi. In this study two methods were implemented, i.e. methods frame-spider and methods of nails-natural substrates, with 5 units as replication, respectively. A total of three kinds of branching corals weretransplanted, namely Acropora robusta, Porites cylindrica, and Pocillopora verrucosa. On each unit transplantation models, attached 6 coral fragments with branch length of 5-12 cm for each kind of corals. A total of 3 fragments for each species of corals were labeled and coded for the survival rate and absolute growth monitoring. All five unit of experiments on each model are placed on two areas separately and placed randomly with depths ranging from 3-4 m in the northern part of island. Observations survival rate and absolute growth of coral transplant were conducted for every 2 weeks for 28 days by counting the dead coral fragment or missing and measure the length of transplant coral branch with a measuring ruler. The effectiveness of the two methods was analyzed based on the survival and growth of the absolute value of coral transplant. Survival rate were analyzed descriptively and the average values of absolute growth were analyzed by t-student. The use of frame-spider methods and methods of nails-natural substrates as effective in rehabilitating the coral reefs from bleaching phenomenon based on the parameters of survival and growth of Acropora robusta, Porites cylindrica, and Pocillopora verrucosa Keywords: Transplantation methods, coral reef, bleaching coral, Liukang Loe Island

The study determine the wages models applied by the company in Batam which is expected to provide a wide range of reference models in different strata of wage and cluster companies. It is also expected to help the local government as a factor in determining the minimum wage policy making through recommendations wages models are ideal in Batam. Data was collected using interview techniques to the manufacturing industry in three related units in a company that is human resource, administrative staff and production staff. The results of the study were analyzed qualitatively to explore models that have been applied and the desire of employees. The model has been applied to remuneration in accordance with the general models that already exist, but there are still some wishes of the employees on the compensation of employees in the company they both administrative and production employees. Researchers also analyzed employee satisfaction with the existing system and the results are most of the employees did not feel satisfied with the remuneration system.

Coral disease is one of the threats to the health of coral but is not yet widely known. This study was conducted to determine the types of bacterial associations in hard corals infected with growth anomaly (GA). Coral samples infected with GA disease were taken by using SCUBA tool on Salemo Island, Mattiro Bombang Village, Pangkep District. Bacterial isolation was performed by removing mucus from corals infected by growth anomaly by 1 ml and diluted to dilution 10-3 . Purification of bacteria is done by inoculating the solid medium of Marine Agar. Furthermore, Gram staining and biochemical tests were performed. Bacterial identification was performed based on colony morphology and biochemical reaction test results. The results showed that GA disease can infect coral Porites, Acropora digitate, Platygyra and pocillopora . Bacteria are found from the genus Flavobacterium, Acinetobacter and, Neiseria. Keywords: Bacteria association, coral stone, coral disease, growth anomaly

The purpose of this research is to find out the cut score of graduation for the national exam participants, as we know so far the determined passing score through judgement and the policy of the Government without paying attention to the matter of matter that exists on the test devices, and without involving the experts (as curriculum subjects teachers, expert, assessment expert). Determining graduation like this does not meet the criteria as signaled by experts such as educational measurement experts called in Standards for Educational and Psychological Testing : “When cut scores defining pass-fail, the judgmental process should be designed so that judges on bring their knowledge and experience to bear in a reasonable way”. Scientific method that can be used to determine the score a passing grade is the Angoff method and bookmark method. This method can be used to determine the standard graduation test national became more scientific. ABSTRAKPenelitian ini bertujuan untuk mengetahui batas skor kelulusan (cut score) yang tepat bagi peserta Ujian Nasional (UN). Seperti kita ketahui bahwa sampai saat ini penentuan kelulusan pada Ujian Nasional ditentukan melalui judgement dan merupakan kebijakan yang dikeluarkan oleh Pemerintah tanpa memperhatikan soal-soal yang ada pada paket-paket UN dan tanpa melibatkan tenaga-tenaga ahli (seperti guru bidang studi, ahli kurilukum, dan ahli penilaian).Penentuan kelulusan seperti ini kurang memenuhi kriteria sebagaimana yang diisyaratkan oleh ahli-ahli pengukuran pendidikan, seperti yang disebutkan dalam Standards for Educational and Psychological Testing: “When cut scores defining passfail, the judgmental process should be designed so that judges on bring their knowledge and experience to bear in a reasonable way”Metode ilmiah yang digunakan untuk menentukan standar atau cut score kelulusan pada studi ini adalah dengan menggunakan Metode Angoff dan Bookmark. Metode ini dapat digunakan untuk menentukan standar kelulusan UN menjadi lebih ilmiah.

Since the enactment of the National Standard School Final Examination (UASBN) in school year 2007/2008, the province is authorized to construct exam questions based on the same lattice issued BSNP. No tests ever found two packages with different grain problem, although based on the same grid have the same difficulty level. Therefore, the evaluation of the National Exam level using several different test packets and measuring the same thing, need to be equated. The effect of equating scores on the packages used in this UN estimates that the slightest error of measurement can be known, and the scores obtained can be compared so that the test participants are not disadvantaged or advantaged because of getting an easier or more difficult test package accidentally. The purpose of this Research is to 1) determine the conversion of the value of the subjects to be tested nationally among province, among packages at UASBN.; 2) know the actual ability of the participants UASBN based on the conversion of the values that have been synchronised. In this research, the technique used is equipercentile equating with the use of the software Program for Common Item Equating (CIPE) version 2.0 ABSTRAKSejak diberlakukannya Ujian Akhir Sekolah Berstandar Nasional (UASBN) pada tahun pelajaran 2007/2008, propinsi diberi kewenangan untuk menyusun soal-soal ujian berdasarkan kisi-kisi yang sama yang dikeluarkan BSNP. Para ahli pengukuran menyatakan bahwa tidak pernah ditemukan dua paket tes dengan butir soal yang berbeda walaupun berdasarkan kisi-kisi yang sama mempunyai tingkat kesukaran yang sama. Oleh karena itu dalam pelaksanaan evaluasi setingkat Ujian Nasional yang menggunakan beberapa paket tes yang berbeda dan mengukur hal yang sama, perlu dilakukan penyetaraan (equating). Dengan dilakukannya penyetaraan/equatingskor atas paket-paket yang digunakan dalam UASBN, maka estimasi kesalahan pengukuran yang sekecil apapun dapat iketahui, dan skor yang diperoleh dapat dibandingkan sehingga peserta tes tidak merasa dirugikan atau diuntungkan karena kebetulan mendapat paket tes yang lebih mudah atau yang lebih sukar. Tujuan Penelitian adalah menentukan konversi nilai mata pelajaran yang diujikan secara nasional antarprovinsi, antarpaket pada jenjang pendidikan Sekolah Dasar, dan mengetahui kemampuan sebenarnya dari peserta UASBN berdasarkan konversi skor yang telah disetarakan. Pada penelitian ini, teknik equatingyang digunakan adalah equipercentile equating dengan menggunakan software Common Item Program for Equating(CIPE) versi 2.0.

The isolation of cellulose nanofibers from areca nut shell has been successfully carried out using a simple alkaline treatment, acid hydrolysis, and followed by a morphological modification using low‐energy sonication method. The alkaline treatment consists of dewaxing and bleaching process to remove lignin, while acid hydrolysis process was carried out to remove hemicellulose. Mechanical fibrillation was carried out via ultrasonication and low‐power homogenization with 100 W cleaner and 3 W homogenizer to obtain fine fibers. Following the scanning electron microscope (SEM) result, the ultrasonicated treatment sample showed better lignin and hemicellulose removal processes and increased dispersity, as well as reduce diameter of cellulose fibers from 710.4 to 451.6 nm. The particle size analyzer (PSA) showed that the colloidal cellulose after sonication provide a frequent diameter of 56 nm. Fourier transform infrared (FTIR) spectroscopy result showed that sonication is an effective removal process of noncellulosic components. X‐ray diffraction (XRD) analysis showed that the crystallinity of nanocellulose decrease following the sonication process. Hence, low‐energy ultrasonication is a viable approach to enhance the morphology and mechanical strength of cellulose nanofiber. [ABSTRACT FROM AUTHOR]

This study aims at determining to what extent the entrepreneurial learning design influences students' entrepreneurial competence in the Vocational High School in the Makassar. To achieve that goal, then some data collection techniques were used namely documentation and questionnaires. The data were analyzed using several techniques namely descriptive analysis, validity and reliability test of the research instrument, classical assumption test consisting of normality test, multicollinearity test, and heteroscedasticity test, multiple linear regression analysis, and hypothesis testing consisting of t-test and f-test. Based on the results of regression analysis, it can be concluded that the entrepreneurial learning design has a positive and significant effect on students' entrepreneurial competence in vocational high school in Makassar. Therefore, the first proposed hypothesis is accepted.

This study aims to analyze the effectiveness of communication in learning during training with the BL model. The research employs quantitative survey methods by distributing a questionnaire consisting of 18 attitude statements in Likert scale format (Strongly Disagree, Disagree, Neutral, Agree, Strongly Agree) to be selected by respondents and divided into 3 indicators: Trainer Communication Skills, Participant Engagement, and Learning Interaction. The results of this study indicate that the effectiveness of communication in BL model learning is considered very high by training participants. Trainer communication skills are rated highly, indicating effective skills in delivering content. Participant engagement is also rated highly, showing active participation in learning. Learning interaction is rated highly, creating a conducive learning environment. These findings are relevant for developing future training programs and formulating education policies that consider technology's role in enhancing accessibility and education quality. [ABSTRACT FROM AUTHOR]