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This study is the first review of current research on microplastics (MPs) in the marine environments at the national scale in Indonesia from 2015 to 2022. This review was conducted to measure the environmental risk and highlight the waste management issue in Indonesian waters. Our literature study found that: (1) the MPs research was mainly conducted in the western part of Indonesia, especially in Java Island; (2) current research has primarily focused on coastal waters (98%) rather than the deep-sea area (2%); (3) the comparability of data is still hampered by difference in quality, about 67% of articles published have not carried out the polymer confirmation; (4) MPs concentrations reported on the articles that did not carry out the polymer identification tended to report higher MPs concentrations. Finally, we propose to have a standard guideline for MPs analysis at a national level and to do more research in the eastern part of Indonesia and deep-sea areas. Further research is required to fill research gaps on plastic distribution and density in deep-sea areas in the eastern part of Indonesia.

Tujuan Penelitian ini adalah: (1) Menganalisis peningkatan keterampilan berpikir kritis mahasiswa melalui implementasi ELEMA berbasis student-centered learning dan (2) Menganalisis respon mahasiswa terhadap implementasi ELEMA berbasis student-centered learning pada mata kuliah Zoologi Invertebrata. Rancangan penelitian ini adalah One Group Pretest-Posttest Design. Sampel penelitian ini adalah mahasiswa aktif semester 3 (tiga) Program Studi Pendidikan Bologi FKIP Universitas Palangka Raya yang memprogramkan mata kuliah Zoologi Invertebrata. Data keterampilan berpikir kritis mahasiswa dianalisis secara kuantitatif menggunakan rumus n-gain. Data diolah menggunakan program Microsoft Excel 2019. Hasil penelitian menunjukkan bahwa keterampilan berpikir kritis mahasiswa yang dibelajarkan dengan ELEMA pada mata kuliah Zoologi Invertebrata meningkat dengan rerata gain sebesar 0,71 dalam kategori Tinggi. Respon mahasiswa terhadap implementasi ELEMA dalam perkuliahan Zoologi Invertebrata menunjukkan rata-rata perolehan skor 86,5 yang menunjukkan respon sangat baik.

The COVID-19 pandemic in Indonesia and around the world is still on going. Teaching and learning activities in schools require a change, one of which is by using the internet network (online) to maintain the implementation and quality of learning outcomes. Lesson Study can improve student collaboration skills, teacher collaboration and implementation of learning. The implementation of lesson study (LS) at SMPN 1 Palangka Raya in collaboration with Palangkaraya University has been carried out in 2 cycles. The implementation of LS in Natural Science (IPA) material is carried out by 4 model teachers and 7-8 observers. Each cycle consists of stages: Lesson Design, Redesign, Open Class, and Reflection. The implementation of learning and collaboration of teachers or students is measured using an observation sheet. Observational data were analyzed descriptively and qualitatively. The results showed that collaboration skills between teachers were obtained in the first cycle of 85.94%, an increase in the second cycle of 96.88%. The activity of teachers in one LS Team reached 100%, while during the Open Class in the first cycle it was 80.08% and the second cycle was 76.83%. The implementation of learning for 8 open lessons from 4 teachers for the first cycle was 93.75% and the second cycle was 95.83%. Students' collaboration skills increased from cycle I (77.08%) to Cycle II (91.67%). Thus, the application of LS to online science materials at SMPN 1 Palangka Raya City can be applied to increase collaboration during the covid-19 pandemic

Scientific writing and communication skills of undergraduate students in the Biology Education Program of University of Palangka Raya need to be improved. The purpose of this research was to implement mini-research in animal ecology field practice to train undergraduate students’ scientific writing and communication skills. This descriptive quantitative research used action-research method with two cycles in which each cycle consisted of four stages i.e (1) plan; (2) take action; (3) collect and analyze evidences, and (4) reflect. The data gained were analyzed descriptively and quantitatively. The results showed that the gain score of students’ scientific writing skills based on mini-research assessment was 0.6 (moderate category). Moreover, students' communication skills showed an improvement from cycle 1 to cycle 2 which was assessed during the presentation session. All the findings in this study indicate that the implementation of the mini-research project in the field practice of the animal ecology course helps students to develop scientific writing and communication skills.

Thermal and electrical conductivity studies of Cyclic Natural Rubber nanocomposite with graphene 1 and 2 phr (G1 and G2) and modified 1 and 2 graphenes (mG1 and mG2) have been carried out. Graphene was activated with cetrimonium bromide (CTAB), was isolated from Sawahlunto coal (Bb) by the Hummer modification method. The nanocomposite was fabricated through the mixing solution method using Xylena as a solvent. The characterizations of nanocomposites which were performed by Fourier Transform Infrared (FT-IR) and X-Ray Diffraction (XRD) reveals an interaction between graphene, CTAB and the CNR matrix. Furthermore, Scanning Electron Magnetic (SEM) and Transmission Electron Microscopy (TEM) indicate the particle size to be smaller and particle distribution is more in accordance with CTAB. Thermal analysis of nanocomposites using Differential Scanning Calorimeter (DSC) showed an increase in thermal conductivity from 3.0084 W/mK to 3.5569 W/mK. Analysis of electrical conductivity using the Two-Point Probe shows 2 phr mG (mG2) capable of increasing electrical conductivity from 0.1170 × 10–4 S/cm to 0.2994 × 10-4 S/cm.

Abstract : Material characteristics analysis of Sarulla natural zeolite (SNZ) with base activation has been carried out. The base used was NaOH at various concentrations; 0.2 M, 0.5 M, and 2 M. Base activated catalysts were characterized by X-ray Fluorescence (XRF), X-ray diffractometer (XRD), Fourier-transform Infrared (FTIR) Spectroscopy, Scanning Electron Microscopy (SEM) and gas adsorption analysis using BET method. The procedures applied have caused differences in adsorption and desorption rates as well as the crystallinity values of the catalytic materials. Moreover, the ratio of Si/Al contents has also changed at the lowest concentration. On the other hand, the crystallinity of catalysts has decreased at the highest concentration of base applied. The results are reinforced in FTIR characterization which shows the changes of silanol bonds to become silicate and aluminate. Furthermore, morphological analysis of the catalysts shows that homogenous surface was obtained at low concentration, while rough/lumpy surfaces was obtained at higher concentration. Abstrak : Analisis terhadap karakteristik material dari zeolit alam Sarulla (SNZ) dengan metode aktivasi basa telah dilakukan. Basa yang digunakan ialah NaOH dengan berbagai konsentrasi; 0,2 M; 0,5 M, dan 2 M. Katalis yang telah diaktivasi dengan basa kemudian dikarakterisasi dengan Analisis X-ray Fluorescence (XRF), X-ray diffractometer (XRD), Fourier-transform Infrared (FTIR) Spectroscopy, Scanning Electron Microscopy (SEM) dan Gas Adsorption menggunakan metode BET. Dari hasil penelitian, ditemukan perbedaan pada tingkat adsorpsi dan desorpsi, begitu juga dengan kristalinitas pada material katalis. Lebih jauh, rasio konten Si/Al juga berubah pada basa dengan konsentrasi terendah. Di sisi lain, tingkat kristalinitas dari katalis mengalami penurunan pada basa dengan konsentrasi tertinggi. Hasil ini diperkuat dengan data FTIR yang menunjukkan perubahan ikatan silanol menjadi silikat dan aluminat. Lebih jauh, analisis morfologi pada katalis menunjukkan bahwa permukaan yang homogen didapatkan dari penggunaan basa dengan konsentrasi rendah. Sebaliknya, basa dengan konsentrasi tinggi memberikan bentuk permukaan katalis yang tidak homogen serta kasar.

Tkinesthetic learning style; problem solvinghe purpose of this research was to study the profile of students' mathematical inductive reasoning abilities regarding visual, auditory and kinesthetic learning styles in solving mathematical problems. The research method used is qualitative with a descriptive approach. The results of the study showed that UNIPA mathematics education students tended to study with Visual Learning Styles. Students with this learning style tend to have inductive mathematical reasoning abilities that are better than inductive mathematical reasoning abilities of students learning with auditorial learning styles and those who learn with the kinesthetic learning style. Also, Mathematics Education students of University of Papua do not have the ability to examine the validity of an argument and find patterns or characteristics of mathematical symptoms to generalize. DOI: https://doi.org/10.30862/jhm.v1i2.1049

Introduction. Adsorption is a purification process with a more efficient energy level than others. Adsorption performance is strongly influenced by the ability of the adsorbent to be used; therefore, the modification of the adsorbent becomes a very important key for the purification process that occurs. Methods. In this study, the preparation of composite adsorbents was carried out by combining polyvinyl alcohol (PVA), zeolite (Zeo), and activated carbon (AC) as precursors. The crosslinking process was fulfilled by adding glutaraldehyde to the precursor mixtures followed by a supercritical fluid CO2 extraction (SFE) technique to create conditions for the crosslinking process. The composites were analyzed using Braunner–Emmet–Teller (BET) surface area analysis, Fourier-transform infrared (FTIR), differential scanning calorimetry (DSC), and scanning electron microscopy with energy dispersive X-ray (SEM/EDX-mapping), while individual and composite adsorbents were evaluated for their ability in bioethanol dehydration at various initial concentrations of ethanol and temperature. Results. The BET characterization shows that composite preparation under supercritical CO2 conditions provides reasonable surface areas, which are proportional to the content of activated carbon. The crosslinking process has been described by FTIR data interpretation, showing that PVA and glutaraldehyde were properly distributed on Zeo and AC precursors. The DSC characterization results give information that PVA successfully forms hydrophilic composites within Zeo and AC. The SEM micrograph analysis shows the formation of pores on the surface and cross section in structured adsorbents. The experimental adsorption shows that an increasing amount of AC in the composites increases the capacity of water adsorption (i.e., 0.80 gram of water/gram of adsorbent for PVA/Zeo/AC = 1 : 1 : 1 at 22°C). However, the effect is not significant when the ratio of AC is less than 0.5. As expected, the lower temperature increases the adsorption capacity. Further, by using approximately 4.5 gram adsorbents composite in 30 ml of water-ethanol mixtures, high concentration of bioethanol (>99%) can be achieved at various temperatures from 22°C to 40°C and bioethanol initial concentration from 88% to 96%. Conclusion. The SFE technique provides distinguished adsorbents composite properties. Further, the new composites provide about four times better adsorption capacity than that showed in the individual adsorbents test. The addition of AC influences on increasing the capacity and adsorption kinetics value.

Sintesis superabsorben hidrogel CMC-g-PAA yang berikatan silang telah dibuat dengan kopolimerisasi cangkok (grafting) radikal bebas menggunakan karboksi metil selulosa (CMC), asam akrilat (AA), kalium persulfat (KPS) sebagai inisiator dan N, N’-metilen bisakrilamid (MBA) sebagai crosslinker. Pengaruh konsentrasi crosslinker terhadap asam akrilik (3,13 ; 3,75 dan 4,38 %w/w) telah dipelajari berdasarkan sifat mengembang (swelling properties). Struktur kimia yang terjadi dianalisa menggunakan spektroskopi Fourier Trasform Infra-red (FTIR). Hasil dari spektrum FTIR memperlihatkan bahwa CMC dalam polimerisasi cangkok bereaksi dengan asam akrilat. Pada jumlah crosslinker 3,75% w/w diperoleh kamampuan menyerap air (equilibrium swelling) maksimum 49,62 g/g dalam air distilat dan 20,42 g/g dalam larutan NaCl 0,9 %.

Constituents of liquid smoke possess a huge potential to be converted as value-added chemicals, such as flavoring, antiseptics, antioxidants, or even fossil oil substitutes. However, liquid smoke instability, led by the presence of oxygenate compounds, is an obstacle for further utilization and processing. On the other hand, catalyst efficiency in hydrodeoxygenation (HDO) remains challenging. Sarulla natural zeolite (Z), with abundant availability, has not been comprehensively investigated in the catalytic performance of HDO. In this study, Sarulla natural zeolite with different Si/Al ratios, which are activated by several concentrations of hydrochloric acid and nickel supported by Z (Ni-Z) synthesized by wet impregnation, were evaluated for HDO of liquid smoke, particularly in reducing oxygenate compounds. Catalyst morphology, surface area, pores, and crystallinity are investigated. Catalytic performances were evaluated, particularly on reducing oxygenate compounds and the shifting of phenol and its derivatives. Furthermore, the liquid smoke product of HDO was analyzed by gas chromatography-mass spectrometry (GC-MS). The data obtained reveal that the HDO process of liquid smoke with the Z3 catalyst shows the best activity compared to Z5 and Z7, with phenol conversion of 62.39% and 11.93% of alkoxy reduction. Meanwhile, the best Ni metal catalyst system activity was given by the Ni-Z5 catalyst compared to Ni-Z3 and Ni-Z7, where phenol conversion and alkoxy reduction were at 60.06% and 11.49%, respectively.

A number of studies investigated how financial information affected investment decisions. The study extendedthis line of research by examining the effect of risk, proxied by price per share, number of shareholders, numberof dealers, trading volume, accounting risk and market risk measures on the bid ask spread. Further, theresearch tried to test the relationship between bid ask spread and cost of equity capital. The samples of thisresearch were the manufacturing companies listed at Indonesian Stock Exchange which shared the dividendfor 3 years; there were 40 companies. Data analysis technique used multiple regression analysis. The results ofregression provided evidence of statistically significant effect of price per share, market value, asset size andprice variability on bid ask spread. At last, there was a positive relationship between bid ask spread and cost ofequity capital

Background. We investigate the immunogenic properties of chitosan and liposome nanoparticles as adjuvant codelivery against a commercial pneumococcal conjugate vaccine (PCV) in an animal model. Methods. The chitosan and liposome nanoparticles were prepared by ionic gelation and dry methods, respectively. The PCV immunization was performed intradermally in the presence of adjuvants and booster injections which were given without an adjuvant. The Quil-A® was used as a control adjuvant. The ELISA was performed to measure the antibodies against pneumococcal type 14 polysaccharide (Pn14PS). Results. The level of total antibodies against Pn14PS antigen was no different between the mouse groups with or without adjuvant codelivery. Codelivery of the PCV with chitosan nanoparticles as well as the Quil-A adjuvant elicited IgG1, IgG2a, IgG2b, and IgG3 antibodies. Meanwhile, codelivery of liposome nanoparticles elicited mainly IgG1 antibodies against the Pn14PS. Conclusions. The chitosan and liposome nanoparticles as adjuvant codelivery were successfully synthesized. These nanoparticles have different shapes in particle formation, liposome nanoparticle with their unilamellar shape and chitosan nanoparticles in large shape due to the aggregation of small-size particles. Codelivery of chitosan nanoparticles has more effect on the IgG subclass antibody production than that of liposome nanoparticles in a mouse model.

Blumea balsamifera D.C, Croton tiglium L, Metroxylon sagu Rottb,and Fagraea racemosa Jackwere used as traditional anti-fertilty of Dayak people in Central Kalimantan. These study are to find out the potential plant as anti-fertility on Swiss Webster (SW) mice. Extracts of Blumea balsamifera D.C, Croton tiglium L, Metroxylon sagu Rottb andFagraea racemosa Jack were administered by gavage at the dose level of 0.26 mg/kg body weight (bw) to female of SW mice for 8 days to examined of estrous cycle.To determine of anti-fertility were administered by gavage of 0.26 mg/kg bw of plant extract to female SW mice and mated with normal male of SW mice. Estrous cycle were analyses every day for 9 days and reproduction display were examined at 15 days after fertilization. The result showed, that estrous cycle are inhibited on estrus and metestrus phase for all of extract traditional plant. Reproduction display showed decrease in the number of live fetuses, number of corpus luteum and body weight of the dam mice treated. The decrease in the corpus luteum further and fetuses attributes antifertilty effect of extract to inhibited foliculogenesis. Out of four extracts tested, Blumea balsamifera D.C extract seems to be more potent in anti-fertility activities compared with other extract of traditional plant.

Innovation is one of the most critical issues in research institutions which can be performed through certain routes within the technology transfer mechanism. As the demands of research implementation are increasing, a better mechanism should be deployed to foster innovation. This study will investigate the possibilities for technology transfer mechanism improvements by (i) identifying a number of steps required for innovation; (ii) measuring the efficiency of each step; and (iii) exploring the most efficient routes to innovate through the Dijkstra algorithm. Cases of research on essential oils and derivatives in the Research Center for Chemistry (RCC) of the Indonesian Institute of Sciences (LIPI) will be examined as the working example for the study. As a result of this study, a model containing a recommended sequence for the most efficient steps to innovation can be proposed. Using the proposed model, the efficiency rate of the technology transfer mechanism was increased twice, suggesting the possibility of stimulating innovation performance.

Methoxyacetic acid (MAA) causes digit malformations of mice when it was given orally on gestation day 11. Previous observation showed that malformation was caused by cell death. The aims of the research were to determine the types of cell death, first time of cell death and their distribution pattern on forelimb bud of Swiss Webster (SW) mice. Ten mM/kg of body weight (bw) of MAA were administered by gavage to SW mice on gestation day 11. Forelimb bud of mouse embryos of gestation day 11 + 0, 1, 2, 3, 4, 5 hours were processed with paraffin method and were made plantar section. Cell death at plantar section were colored with 4,6-diamino-2-phenylindole hydrochloride (DAPI) and hematoxylin. The result showed, that digit malformations initially by apoptosis mesenchymal cell at proximal of axial mesoderm in around of primary axial artery has done one hour after treatment. Apoptosis at the axial area, the site formation of digital ray III distributed to preaxial area where digits I and II are formed, and to the site formation of digits IV and V. The number of mesenchyme cell of digital rays II, III, and V was decrease by the increasing of gestation day, while digital ray was not formed and finally digits I, II, III, and V were missing. The reduction number of cell of digital ray IV were delayed time to be formed and its small size. Thereby it can be concluded, that MAA induced digit malformations of SW mice started by apoptosis which is occurrence has been increase in area of digital ray formation, so that digital ray can not be formed, but when formed it will not developed.

Beberapa kegiatan litbang tentang kemasan yang ramah lingkungan (biodegradable) telah berhasil membuat kemasan dengan extruksi blow moulding dalam skala laboratorium bahkan skala pilot. Untuk mencapai plastik ramah lingkungan telah dilakukan litbang dan diperoleh nanokomposit berbasis polimer termoplastik (polietilen: LLDPE, HDPE dan LDPE, juga polipropilen : PP MF110 dan PP MF135) dengan filler CaCO3 dan tapioka berukuran nanometer. Disamping itu dilakukan litbang dengan filler CaCO3 berbagai bentuk : Calsite, Aragonite dan Vaterite. Nanokomposit dengan filler CaCO3 mencapai komposisi 55 %berat untuk matriks HDPE dan 70 %berat untuk matriks LLDPE, sedangkan untuk PP MF110 mencapai 70 %berat dan PP MF135 sebesar 65 %berat. Sementara itu untuk nanokomposit dengan filler tapioka, hampir seluruh matriks polimer termoplastik (polietilen dan polipropilen) dapat mencapai komposisi sebesar 75 %berat. Hasil uji biodegradable (soil butiral test) nanokomposit menunjukkan bahwa komposisi diatas 50 %berat mengalami degradasi (hancur) dalam waktu 2 (dua) bulan, kecuali LLDPE dengan waktu 4 (empat) bulan. Untuk komposisi dibawah 50 %berat, diperoleh HDPE selama 8 (delapan) bulan dan LLDPE selama 12 (dua belas) bulan. Sedangkan nanokomposit dengan filler tapioka mengalami degradasi (hancur) dalam waktu 1 (bulan) untuk komposisi diatas 50 %berat.

T-2 toxin is a toxic and teratogenic mycotoxin produced by Fusarium tricintum which may contaminate cereal, seed, and food. The aim of this research is to find out the effects of T-2 Toxin on preimplantion embryos and fetuses of Swiss Webster mice. Pregnant female of Swiss Webster mice on 0 or 2 day of gestation was injected intraperitoneally with T-2 toxin at doses 0.05 or 0.10 mg/kg body weight (bw) and the dam was observed at 3.5 and 18 days of gestation. At 0 day of gestation, embryos were arrested at one to eight cell and uncompacted morulae stages (P < 0.01) compared to control, in both 0.05 and 0.10 mg/kg bw doses. The cell numbers of late blastocyst at all treated groups were decreased significantly compared to control. At 2 day of gestation, most of embryos were arrested on compacted morulae stage at dose 0.10 mg/kg bw (P < 0.01), the late blastocyst and its cell number were dose-dependently decreased. The live fetuses decreased significantly at all dose of T-2 toxin. No external malformation occurred in the fetuses. Results showed that T-2 toxin given at preimplantation stages inhibited development of preimplantation embryos as indicated by decreased number of live fetuses. Therefore, it was grouped as embryotoxic agent but those dosages did not cause malformation of the external appearance of Swiss Webster mice fetuses.

T-2 toxin is a toxic and teratogenic mycotoxin produced by Fusarium tricintum which may contaminate cereal, seed, and food. The aim of this research is to find out the effects of T-2 Toxin on preimplantion embryos and fetuses of Swiss Webster mice. Pregnant female of Swiss Webster mice on 0 or 2 day of gestation was injected intraperitoneally with T-2 toxin at doses 0.05 or 0.10 mg/kg body weight (bw) and the dam was observed at 3.5 and 18 days of gestation. At 0 day of gestation, embryos were arrested at one to eight cell and uncompacted morulae stages (P < 0.01) compared to control, in both 0.05 and 0.10 mg/kg bw doses. The cell numbers of late blastocyst at all treated groups were decreased significantly compared to control. At 2 day of gestation, most of embryos were arrested on compacted morulae stage at dose 0.10 mg/kg bw (P < 0.01), the late blastocyst and its cell number were dose-dependently decreased. The live fetuses decreased significantly at all dose of T-2 toxin. No external malformation occurred in the fetuses. Results showed that T-2 toxin given at preimplantation stages inhibited development of preimplantation embryos as indicated by decreased number of live fetuses. Therefore, it was grouped as embryotoxic agent but those dosages did not cause malformation of the external appearance of Swiss Webster mice fetuses.

One of the factors that could influence the degree of conversion of composite restorative material is light intensity. Many researchers have done investigation on the degree of conversion of hybrid, microfiller and microhybrid composite. However, there are still minimum researches on the influence of light intensity on the degree of conversion of nano particle composite which is one of the new universal composite that has been developed in dentistry. The used material was Supreme XT nano particle composite (3M ESPE Germany). Cylindrical specimens with 3 mm in diameter, 2 and 3 mm thickness were prepared. Specimens were cured by Light Emitting Diode (LED) with light intensity variation of 1120, 1040, 800, 560 and 480 mW/cm2, and then incubated for 24 hours at 37ºC. Fourier Transform Infra Red (FTIR) was used to determine the degree of conversion. The data were analyzed statistically by using two-way anova and tukey post hoc test. Based on statistic result at α=0.05 light intensity variation gave significant difference on the degree of conversion of nano particle composite. The highest degree of conversion was achieved with 800 mW/cm2 light intensity, which is 89.67%. The 2 and 3 mm thickness gave no significant difference on the degree of conversion. This research shows that the variation of light intensity has significant influence towards the degree of conversion of nano particle composite.