bluuebunny/crossref_metadata_2025 huggingface dataset:
Synthesis of activated carbons from water hyacinth biomass and its application as adsorbents in water pollution control
Authors: Mohammaad Ahmad , Kijevcanin Mirjana
Published: February 2022

The water hyacinth biomass was used for the synthesis of activated carbons in a process of chemical activation with ZnCl2, followed by controlled pyrolysis. The applied impregnation weight ratios ZnCl2 and dry hyacinth biomass were in the range of 0.5?3.5. The carbonization was conducted at four different temperatures (400?700?C) under an inert atmosphere. The highest yield of activated carbon was obtained for the impregnation ratio of 0.5 and carbonization temperature of 400?C. The samples were characterized using elemental analysis, adsorption?desorption isotherms of nitrogen and SEM analysis. The activated carbon obtained with an impregnation ratio 2.0 and carbonization temperature of 500?C (2.0AC500) showed the highest values of specific surface area and total pore volume of 1317 m2 g-1 and 0.697 cm3 g-1, respectively. The adsorption of glyphosate, pesticide with a strong negative environmental impact, was a fast process, with the equilibrium time of 120 min. The adsorption isotherms were fitted with Langmuir and Freundlich model. The Langmuir adsorption capacity of qmax = 240.8 mg g-1 for 2.0AC500 classified the selected adsorbent as a very efficient one. The tested adsorption process followed the kinetics of the pseudo-second-order model.
On inelasticity of damaged quasi-rate-independent orthotropic materials
Authors: Micunovic Milan , Kudrjavceva Ljudmila
Published: February 2022

The paper deals with a body having a random 3D-distribution of two-phase inclusions: spheroidal mutually parallel voids as well as differently oriented reinforcing parallel stiff spheroidal short fibers. By the effective field approach the effective stiffness fourth-order tensor is formulated and found numerically. Simultaneous and sequential embeddings of inclusions are compared. Damage evolution is described by modified Vakulenko?s approach to endochronic thermodynamics. A brief account of the problem of effective elastic symmetry is given. The results of the theory are applied to the damageelasto- viscoplastic strain of reactor stainless steel AISI 316H.
Financial Auditing as an Economic Service
Authors: Driskill Matthew W. , Knechel W. Robert , Thomas Edward
Published: February 2022

This article summarizes Knechel, Thomas, and Driskill (2020), conceptualizing financial auditing as an economic service. In contrast to the production of tangible goods, a central characteristic of economic services is substantial customer/client participation in the production process. Financial auditing is an intensive collaborative network service due to the multiple parties involved in the production and consumption of the resulting output. This introduces significant heterogeneity and complexity into the planning and conduct of the audit, the resulting audit output, and perceptions of audit quality. While the independence of the auditor is necessary, ignoring the essential nature of auditor-client cooperation may generate unexpected costs which impair audit quality. The multitude of parties involved in an audit creates tension between audit quality and audit efficiency and makes objective definitions of audit quality difficult. Excessive standardization of the audit process may not increase audit quality.

JEL Classifications: G18; G28; G34; G38.
The Effect of Tax Avoidance on Capital Structure Choices
Authors: Lee Yoojin , Shevlin Terry , Venkat Aruhn
Published: February 2022

Existing studies find that tax avoidance affects the cost of debt and equity in different ways but does not examine the consequences of these associations. This study examines a direct and important implication of the effect of tax avoidance on the cost of debt and equity: capital structure choices. Using logit regressions, we find that tax avoidance is positively associated with the probability of issuing equity rather than debt. We use mediation (i.e., path) analyses to provide evidence that the effects of overall tax avoidance and risky tax avoidance on pre-corporate tax cost of equity and debt partially explain our main effects. For stronger identification, we exploit a plausibly exogenous Ninth Circuit decision to implement a difference-in-differences design. Finally, we find indirect evidence that managerial focus on GAAP effective tax rate to estimate the after-tax cost of debt (Graham, Hanlon, Shevlin, and Shroff 2017), partially explaining our main results.
U.S. Multinational Companies’ Payout and Investment Decisions in Response to International Tax Provisions of the Tax Cuts and Jobs Act of 2017
Authors: Beyer Brooke D. , Downes Jimmy F. , Mathis Mollie E. , Rapley Eric T.
Published: February 2022

The Tax Cuts and Jobs Act of 2017 (TCJA) dramatically changed U.S. taxation of foreign earnings for U.S. multinational companies (MNCs). Specifically, the TCJA required taxation of existing unremitted foreign earnings through a deemed repatriation and effectively eliminated future repatriation taxes through a 100 percent dividends received deduction. Additionally, the bill introduced the global intangible low-taxed income (GILTI) regime. We examine MNCs’ responses to the TCJA and find that spending and investment behavior depends on liquidity, investment opportunities, and borrowing costs. Domestic capital expenditures and share repurchases increased for MNCs with low domestic liquidity and high domestic investment opportunities. In contrast, MNCs with low domestic liquidity (high cost of debt) and low domestic investment opportunities increased dividends (decreased debt). Finally, we find that MNCs with high foreign cash and most vulnerable to the GILTI regime increased their foreign but not domestic capital expenditures—a potential unintended consequence.

Data Availability: Data are available from the public sources cited in the text.

JEL Classifications: F23; G31; G38; H25; M40; M48.
Disaggregated versus Holistic Performance Evaluations in a Promotion Setting
Authors: Chan Eric W. , Thornock Todd A.
Published: February 2022

We examine how a holistic versus disaggregated performance evaluation system affects supervisors' subjective evaluations of their subordinates in a promotion setting. A survey of actual supervisors and subordinates indicates that, compared to a holistic system, respondents prefer a disaggregated system and believe it provides more useful feedback and gives a fairer evaluation. We next conduct an experiment with M.B.A. students to examine whether the two types of evaluation systems can lead supervisors to rate their subordinates' job performance differently in a promotion setting. Results indicate that when supervisors are concurrently considering which subordinate to promote in the future, they inflate the overall rating of the subordinate who is best suited for promotion under a holistic system, but not under a disaggregated system. Results from a supplemental experiment suggest that supervisors under a holistic system mentally inflate the rating of the specific performance measure most relevant to the upcoming promotion decision.

Data Availability: Data available upon request.
N-Hydroxyethyl-1-Deoxynojirimycin (Miglitol) Restores the Counterregulatory Response to Hypoglycemia Following Antecedent Hypoglycemia
Authors: Jokiaho Anne J. , Winchester Matthew , Donovan Casey M.
Published: February 2022

Antecedent hypoglycemia suppresses the counterregulatory responses to subsequent hypoglycemic episodes, which can be prevented by normalizing portal-mesenteric vein (PMV) glycemia alone during the antecedent bout. Since the sodium–glucose transporter 3 receptor has been implicated in PMV glucosensing, we hypothesized that PMV infusion of the sodium–glucose cotransporter 3 receptor agonist N-hydroxyethyl-1-deoxynojirimycin (miglitol) would rescue the sympathoadrenal response to subsequent hypoglycemia. Rats underwent hyperinsulinemic-hypoglycemic clamps on 2 consecutive days without miglitol infusion (antecedent hypoglycemia without miglitol [HYPO]) or with miglitol infused upstream in the PMV, perfusing the glucosensors, or adjacent to the liver, bypassing PMV glucosensors, on day 1 or day 2. Control animals underwent day 1 euglycemic clamps, followed by hypoglycemic clamps on day 2. Peak epinephrine (EPI) responses for HYPO on day 2 were significantly blunted when compared with controls. Miglitol infusion on day 1 proved ineffective in restoring the EPI response following antecedent hypoglycemia, but day 2 miglitol infusion restored EPI responses to control levels. As norepinephrine and glucagon demonstrated similar responses, day 2 administration of miglitol effectively restored the counterregulatory response following antecedent hypoglycemia. In subsequent experiments, we demonstrate similar results with reduced miglitol infusion doses, approaching those currently prescribed for type 2 diabetes (correcting for rodent size), as well as the efficacy of oral miglitol administration in restoring the counterregulatory responses following antecedent hypoglycemia.
T-Cell Receptor/HLA Humanized Mice Reveal Reduced Tolerance and Increased Immunogenicity of Posttranslationally Modified GAD65 Epitope
Authors: Jing Yi , Kong Yuelin , McGinty John , Blahnik-Fagan Gabriele , Lee Thomas , Orozco-Figueroa Stephanie , Bettini Matthew L. , James Eddie A. , Bettini Maria
Published: February 2022

Accumulating evidence supports a critical role for posttranslationally modified (PTM) islet neoantigens in type 1 diabetes. However, our understanding regarding thymic development and peripheral activation of PTM autoantigen-reactive T cells is still limited. Using HLA-DR4 humanized mice, we observed that deamidation of GAD65115–127 generates a more immunogenic epitope that recruits T cells with promiscuous recognition of both the deamidated and native epitopes and reduced frequency of regulatory T cells. Using humanized HLA/T-cell receptor (TCR) mice, we observed that TCRs reactive to the native or deamidated GAD65115–127 led to efficient development of CD4+ effector T cells; however, regulatory T-cell development was reduced in mice expressing the PTM-reactive TCR, which was partially restored with exogenous PTM peptide. Upon priming, both the native-specific and the deamidated-specific T cells accumulated in pancreatic islets, suggesting that both specificities can recognize endogenous GAD65 and contribute to anti–β-cell responses. Collectively, our observations in polyclonal and single TCR systems suggest that while effector T-cell responses can exhibit cross-reactivity between native and deamidated GAD65 epitopes, regulatory T-cell development is reduced in response to the deamidated epitope, pointing to regulatory T-cell development as a key mechanism for loss of tolerance to PTM antigenic targets.
Antibacterial properties of silver nanoparticles synthesized via nanosecond pulsed laser ablation in water
Authors: Ruiz Samuel , Wang Fei , Liu Lei , Lu Yongfeng , Duan Bin , Korshoj Lee E. , Kielian Tammy , Cui Bai
Published: February 2022

Ag nanoparticles were synthesized in pure water by a nanosecond pulsed laser ablation process and characterized using transmission electron microscopy and ultraviolet-visible spectroscopy. The as-synthesized nanoparticles were determined to have an average particle size of 10.17 ± 2.95 nm. Their absorption spectra were consistent with that of Ag nanoparticles produced through chemical methods. The antibacterial properties of Ag nanoparticles at concentrations of 100 and 250 μg/ml were studied against the gram-positive bacterium Staphylococcus aureus at two infectious inocula (103 and 105 CFU/ml). Over a 24-h test period, the samples containing 100 μg/ml exhibited early bacteriostatic activity but did not stop long-term bacterial growth, while the 250 μg/ml samples demonstrated bactericidal and bacteriostatic effects. These results highlight the use of Ag nanoparticles synthesized through laser ablation as green and effective antibacterial agents for biomedical applications.
Facial Nerve Neuropathy Caused by its Stretching
Authors: Tymofieiev Oleksii , Kryvosheieva Anna , Beridze Beka
Published: February 2022

Purpose.
Study the dynamics of changes in electrophysiological parameters of the facial nerve in cases after operative interventions on the parotid and submandibular glands, as well as determine the possibility of using electrical stimulation of the nerve on the hardware-software complex “DIN-1” for the treatment of neuropathy caused by its stretching.
Patients and Methods.
31 patients were examined after surgery on the parotid and submandibular glands.
Results.
Based on the performed patient examinations after parotidectomy and extirpation of the submandibular glands, it was established that in the postoperative period they may have neuropathy of the facial nerve, the cause of which is the stretching of the nerve. Clinical improvement and elimination of symptoms were correlated with normalization of electrophysiological indices of the state of affected branches of the facial nerve.
Conclusions.
Due to the use of the hardware-software complex “DIN-1” for diagnosis and treatment of the facial nerve neuropathy caused by its stretching, we managed not only to identify and prove the existence of this disease, but also to shorten the terms of rehabilitation of patients 4 times.
Keanekaragaman Burung di Sungai Mamberamo, Papua (Short Communication)
Authors: Pattiselanno Freddy
Published: February 2022

TheMamberamo-Rouffaer-IdenburghRiverwatershed, one of the wetland sites inWest Papuais the largest tropical marshlands in northern Papua, covers 7,711,602 hectares and includes in the North Papuan Lowlands Endemic Bird Area (EBA). The Irian Jaya Biodiversity Conservation Priority-Setting Workshop (Conservation International, 1999) highlighted that theMamberamoBasinis an area with high priority for conservation. It is also acknowledged little biological information has been collected therefore it is urgent to carry out biological and ecological study in this particular sites.
Keragaman Jenis Mamalia Kecil di Toraut, Taman Nasional Bogani Nani Wartabone Sulawesi
Authors: Maharadatunkamsi Maharadatunkamsi
Published: February 2022

Penelitian ini merupakan kegiatan inventarisasi mamalia kecil di Toraut, Taman Nasional Bogani Nani Wartabone,SulawesiUtara. Pada penelitian ini dilakukan pengamatan diversitas mamalia kecil pada dua habitat utama yaitu hutan dan perkebunan, yang masing-masing diamati selama enam hari. Empat puluh perangkap kawat digunakan untuk mendokumentasi jenis-jenis tikus dan empat buah jaring kabut untuk kelelawar, serta pengamatan langsung di lapangan. Dalam penelitian ini dapat didokumentasikan sebanyak 129 ekor mamalia kecil yang terdiri dari 12 jenis.Limajenis di antaranya endemikSulawesidan tiga jenis mempunyai status konservasi dari IUCN.
Purifikasi dan Karakterisasi Krom Reduktase Bacillus sp LKA9
Authors: Ali Alimuddin , Soetarto Endang Sutariningsih , Widada J. Sri
Published: February 2022

Chromate reductase is one of the potential enzymes for hexavalent chrom detoxification. Most of the enzyme is produced by bacteria, especially Bacillus. The aim of this research was to study chromate reductase activity isolated from Bacillus sp LKA9. Bacillus sp LKA9 was isolated from leather tannery liquid waste and used as a model in the experiment. Bacillus sp LKA9 was isolated through enrichment culture using Salt Base Solution containing 3 mM K2CrO4. Chromate reductase was isolated from bacteria by growing on a liquid medium containing chrom hexavalen (Cr VI) through several steps. The first step of the isolation process was to use the precipitated process using ammonium sulphate (30-80%). The next step, crude enzymes from the first step was partially purified through DEAE-Cellulose of Ion Exchange Chromatography Column. Diphenylcarbazide methods was used to examine the activity of enzyme fractions. The result of the experiment revealed that all protein could be precipitated by ammonium sulphate, and the cytoplasmic fraction at saturation of 50-70% showed high enzyme activity. Purified enzymes showed an increase activity 69,385 times to that of crude enzymes. The enzyme optimal had temperature and pH were 350C and 5; respectively. KM of enzyme was 0,0075 mM, and Vmax was 2500 mol/minute/mg protein. Enzyme activity was not inhibited by Cu2+, but an ion Ag2+ and Hg2+ inhibited the enzyme activity un-competitive. The activity of enzyme was demonstrated on SDS-PAGE by appearing typically band with molecular weight 29,26 kDa, it was assumed as chromate reductase.
Uji Aktivitas Antibakteri dan Sitotoksik Ekstrak Metanol Aglaia silvestris (M.Roemer) Merr.
Authors: Praptiwi Praptiwi
Published: February 2022

The antibacterial and sitotoxic activities of ganggo (Aglaia silvestris (M.Roemer) Merr. methanol extract were determined in this study. Antibacterial in-vitro test of ganggo methanol extract was exposed to Gram positive (Staphylococcus aureus ATCC 25923, Streptococcus agalactiae ATCC 8190, and Streptococcus sp.) and Gram negative (Salmonella typhii NCTC 786 E, Eschericia coli ATCC 25922, and Pseudomonas pseudomallei ATCC 15682) bacteria. The extract concentrations were 50, 25 and 12.5%, and done in triplicate. The growth inhibition area of extract was compared to those of standard antibiotic (10 unit ampicilin). Cytotoxic test of ganggo extract was done utilizing Brine Shrimp Lethality Test (BST) with Artemia salina.The result showed that growth inhibition area of 12.5% ganggo methanol extract to P. pseudomallei (19 mm) was wider than that of 10 unit ampicilin (0 mm). It showed that P. pseudomallei was sensitive to ganggo methanol extract. The result of BST showed that LC50 of ganggo extract was 345.44 ppm. It was concluded that ganggo methanol extract had antibacterial effects on some bacteria isolates and had cytotoxic effects with LC50 345.44 ppm.
Pengaruh Variasi Fotoperiodisitas terhadap Pertumbuhan Chlorella dalam Medium Basal Bold
Authors: Prihantini Nining , Rachmayanti Winny , Wardhana Wisnu
Published: February 2022

The research of photoperiodicity effect on the cell densities of genus Chlorella grown in Bold’s Basal Medium (BBM) had been done. Observations were done for 14 days. Research was experimental study with full random design to 8 varieties of photoperiodicity i.e. 6 h light/18 h dark (L/D) cycles, 8 h light/16 h dark (L/D) cycles, 10 h light/14 h dark (L/D) cycles, 12 h light/12 h dark (L/D) cycles, 14 h light/10 h dark (L/D) cycles, 16 h light/8 h dark (L/D) cycles, 18 h light/6 h dark (L/D) cycles, and 24 h light/0 h dark (L/D) cycles. On peak culture, 24 h light/0 h dark (L/D) cycles produced the highest cell numbers (204.680.000 cell/ml) and the lowest cell numbers were achieved by culture with 6 h light/18 h dark (L/D) cycles. Kruskall-Wallis test showed that there were some effects of photoperiodicity variations on cell numbers of Chlorella (cell/ml) in culture (p>0.05). Multiple comparison tests showed that mean of cell numbers of Chlorella (cell/ml) differ (p>0.01) on every photoperiodicity. Relationship between photoperiodicity and cell numbers of Chlorella was determined by regression equation Ŷ = 24634821,214 + 21977643,869 X.
Kehadiran Mamalia pada Sesapan (Salt lick) di Hutan Lindung Taratak, Kabupaten Pesisir Selatan, Sumatera Barat
Authors: Novarino Wilson , Kamilah Santi N , Nugroho Agung , Janra M. Nazri , Silmi M. , Syafrie M.
Published: February 2022

The study of mammals visitation on salt licks in protected forest of Taratak, SoutheraCoast of West Sumatra was conducted from June to September 2005 (in total 6840hours.camera). Three camera traps were deployed separately on three salt lick areas.Nine species of mammals were recorded during the study. Tapirus indicus was thespecies most often photographed (13.5%), followed by Presbytis melalophos (11.3%) andSus scrofa (9.8%). This study also records the activity of human on salt licks areas. Thenumbers of visitation of mammals on three salt licks area differed, both in the numberof species and the number of individual. The differences of mammal visitation on saltlicks were not affected by size, altitude, and distances from village. The results alsoshowed that there was time segregation when entering the salt licks area, both interrestrial mammals and primates.
Periode Pemijahan Spons Aaptos aaptos (Porifera: Demospongia) di Perairan Pulau Pari, Kepulauan Seribu, DKI Jakarta
Authors: Kawaroe Mujizat , Soedharma Dedi , Siregar Rahmadsyah Deny
Published: February 2022

The purpose of this research was to study spawning period of sponge Aaptos aaptosat Pari Island, Thousand Islands, DKI Jakarta. The result showed that spawningtime occurred at 17.00-18.00, and within that time the sponge closed their osculumto throw out the zygote leaving the body faster. The duration of spawning rangefrom 4 minutes to 41 minutes. Based on the lunar periode, spawning for spongeAaptos aaptos started from early new moon till few days after full moon. Spawningmostly took place during spring tides. Based on the PCA analysis, it was found thatwater temperature and pressure had strong correlation with spawning time.
Isolasi Bakteri Mananolitik dan Karakterisasi Mananasenya
Authors: Meryandini Anja , Anggreandari Rizky , Rachmania Nisa
Published: February 2022

Isolate RA05 has the highest mannanolytic index and mannanase activity which isolated from copra soil waste from Pasaman, West Sumatra. The best growth condition that produces best mannanase activity of isolate RA05 was achieved from 500 ml flask containing 100 ml medium with 100 rpm agitation. Isolate RA05 showed its mannanase activity in medium containing Locust Bean Gum and coconut meal but not in medium containing kolang kaling. This mannanase had the highest activity on medium containing 2% of coconut meal with optimum condition temperatur 800C and pH 2.5. Adding of 5 mM MnCl2 on the crude enzym increased the activity near 300%. Other kation (Ca2+, Zn2+, Cu2+, Mg2+, Fe2+ dan Co2+) did not display great effect on the activity.
Kondisi Optimum untuk Produksi Kitinase dari Streptomyces Rkt5 dan Karakterisasi pH dan Suhu Enzim
Authors: Yurnaliza Yurnaliza , Margino Sebastian , Sembiring Langkah
Published: February 2022

Chitinase is chitin degrading enzyme which is produced by Streptomyces Rkt 5 is isolated microorganism from peanut rhizosfer. This enzyme and its microorganism can be used in many agricultural, medicine and industrial purposes. The aim of the research was to find out the optimum condition for production of chitinase and to characterize of pH and temperature to chitinase activity. Optimalizing production the research had 4 treatments. The optimum conditions were achieved at mineral liquid medium containing with chitin 0,2% (w/v) as inducer, 10% (v/v) inoculum, pH 7 and 48 hours incubation. The crude enzyme was partially purified by salting out with 70% ammonium sulfate resulted in 3.31 time more purity enzyme than the crude one. This enzyme had maximum activity at 50oC and pH 5.5.
Diatom dan Paleolimnologi: Studi Komparasi Perjalanan Sejarah Danau Lac Saint-Augustine Quebeq-City, Canada dan Danau Rawa Pening Indonesia
Authors: Soeprobowati Tri Retnaningsih , Hadisusanto Suwarno
Published: February 2022

Diatoms are a micro-alga dominates in the aquatic ecosystem. Their silicious cell wall able to preserve death diatoms in the sediment for long periods of time, therefore, diatoms have an important role in the paleolimnological analysis. Diatoms assemblages in the sediment layer express the water quality whenever the diatom lives. This article provides information how to apply diatom on the paleo-limnological analysis, supporting with the case study in the Lac Saint-Augustine Quebec-City Canada and Rawa Pening Lake Indonesia. Modern diatom and the water quality from spatial and temporal range are used as a calibration set. The diatoms of below layers, then, Weighted Averaging (WA) with the calibration set to reconstruct the water quality in the past. Previously, both in Canada and Indonesia, those lakes were oligotrophic and sharply change into eutrophic condition since a lot of human activities developed around the lakes (anthropogenic factors). Naturally, the maturity of lake can not avoid and the succession had been fast by eutrophication. Paleolimnological approach provides baseline data in the past to develop the appropriate lake management.
Induksi Mutasi Curcuma zedoaria (Christm) Roscoe dengan Irradiasi Sinar Gamma
Authors: Poerba Yuyu Suryasari , Martanti Diah
Published: February 2022

Curcuma zedoaria (Zingiberaceae) is one of Curcuma spp. used as stomachic,carminative, haematic and styptic medicines. Dried rhizomes of C. zedoaria containessential oil and curcuminoids. Induced mutation of this species would provide andhelp plant breeders to improve and select better quality of the plant. The presentstudy was carried out to determine LD-50% of gamma irradiation of C. zedoaria, toinduce genetic variation using gamma irradiation, and to assess genetic diversityamong mutant genotypes using random amplified polymorphic DNA (RAPD)markers. The LD-50% of gamma irradiation was achieved at 813.32 rad. Chlorophyllmutations were recorded at vM1 and vM2. Result of genetic analysis showed thatRAPD profiles were different from that of the control, and genetic dissimilaritiesamong mutant genotypes were higher than that of the control.
Karakterisasi, Pengaruh Sumber Nitrogen dan Karbon terhadap Produktivitas Enzim Lipase Rhizopus microsporus var oligosporus UICC 550
Authors: Mangunwardoyo Wibowo , Lusini Yuyun , Gandjar Indrawati
Published: February 2022

Effect of nitrogen and carbon source on the production of extracellular lipase by R.microsporus var. oligosporus UICC 550 was studied. The enzyme activity was alsocharacterized in terms of temperature, pH, stability at room temperature, and effectof divalent ion. The amount of 2.5% (w/v) of olive oil as carbon sources and 5% (w/v)peptone as nitrogen sources were the optimum for production of lipase enzyme.Partial purifications using ammonium sulfate followed by dialysis showed that at pH6.5 and temperature 35oC was the optimum condition, respectively. The stability(remaining up to 80% of the optimum enzyme) was recorded at pH 6.5 after 24 hoursincubation at room temperature. The optimum activity remained 40% of the after onehour incubation at 35oC. Divalent ions concentration at 1 mM, Zn2+, Cu2+, Mg2+ andFe2+ inhibited the lipolytic activity.
Construction of Soil Metagenomic Library to Obtain Recombinant Clones with an Indigenous Lipase Activity
Authors: Susanto Agus Hery , Pramono Hendro , Lestari Puji
Published: February 2022

Penelitian ini bertujuan untuk mengonstruksi perpustakaan metagenom tanah dari sekitar lokasi industri pengolahan minyak kelapa di Kabupaten Banyumas, Jawa Tengah, dalam upaya mendapatkan klon rekombinan dengan aktivitas lipase indigenuos. Penelitian dilakukan di Laboratorium Genetika, Fakultas Biologi, Universitas Jenderal Soedirman mulai bulan Mei hingga Desember 2006. Secara umum tahapan penelitian terdiri atas ekstraksi dan pemurnian DNA tanah, isolasi pUC19, pemotongan DNA tanah, pemotongan dan defosforilasi pUC19, ligasi fragmen-fragmen DNA tanah ke dalam pUC19 untuk menghasilkan molekul DNA rekombinan, dan transformasi sel inang E. coli JM109 menggunakan molekul DNA rekombinan yang diperoleh untuk mengonstruksi perpustakaan metagenom tanah. Pemotongan DNA tanah menghasilkan fragmen-fragmen yang sebagian besar berukuran lebih kurang 5 kb sehingga gen lipase dimungkinkan untuk dibawa di dalamnya. Transformasi sel inang E. coli JM109 memperlihatkan efisiensi 1.7 x 105 cfu/μg plasmid. Di antara koloni-koloni yang diperoleh, terdapat 102 koloni berwarna putih, yang menunjukkan keberadaan molekul DNA rekombinan. Koloni putih ini dapat digunakan sebagai materi untuk skrining klon rekombinan dengan aktivitas lipase.
Diversity and Abundance of Ant (Formicidae) Functional Groups in Range of Land Use Systems in Jambi, Sumatra
Authors: Susilo F. X. , Hazairin M. , Hardiwinoto Suryo
Published: February 2022

Kerusakan hutan tropika basah dapat menimbulkan dampak lingkungan berupa penurunan keanekaragaman hayati dan terganggunya fungsi serta stabilitas ekosistem. Tujuan dari penelitian ini adalah untuk mendapatkan bukti apakah perubahan hutan tropika basah menjadi bentuk penggunaan lahan lain berakibat pada penurunan keragaman dan kelimpahan semut, dan untuk menunjukkan apakah semut dapat dijadikan sebagai bio-indikator perubahan sistem penggunaan lahan (SPL). Penelitian ini dilakukan di Jambi Sumatra pada akhir musim penghujan (Mei−Juni) 2004 pada berbagai taraf intensifikasi SPL. Inventarisasi dan koleksi semut dilakukan dengan menggunakan metode “Winkler” pada enam SPL, yaitu: hutan primer, hutan sekunder, perkebunan karet, perkebunan kelapa sawit, ladang ketela pohon, dan padang alang-alang. Hasil penelitian menunjukkan bahwa ditemukan 50 genus semut pada 6 SPL tersebut. SPL tidak berpengaruh secara nyata terhadap keragaman dan kelimpahan seluruh semut tetapi berpengaruh secara nyata terhadap kelompok semut pesaba dan semut predator. Keragaman jenis dan kelimpahan yang tinggi dari semut predator ditemukan pada SPL hutan primer dan hutan sekunder. Keragaman jenis dan kelimpahan menjadi rendah apabila SPL hutan diubah menjadi SPL ladang ketela pohon. Kelimpahan semut pesaba tertinggi diketemukan pada SPL perkebunan kelapa sawit. Data yang diperoleh menunjukkan bahwa semut dapat digunakan sebagai bio-indikator dalam perubahan SPL di kawasan Jambi, Sumatra.
Diversitas Suku Agamidae (Reptilia: Squamata) pada Berbagai Tipe Habitat di Kawasan Pertambangan Emas Martabe, Sumatera Utara: Dalam Tahap Konstruksi
Authors: Riyanto Awal
Published: February 2022

A study of Agamid lizards diversity and their distribution surrounding Martabe Mining project Area, South Tapanuli, North Sumatera was conducted in five different habitat types. The data were gathered by opportunistic searching in each habitat type with two replications. Shannon-Wiener index was used to determine the diversity while the homogeneity was verified by Pielou index. The similarity of Agamid communities among habitat types was confirmed by Sorensen coefficient. As a result, 9 Agamid species were recorded with Draco melanopogon as the major component of Agamid community making up 49.1% of total individuals gathered. Highest diversity occurred in moderately disturbed forest, but the most homogeny took place in riparian lowland forest. The cluster analysis using Sorensen’s coefficient of agamid species distribution among habitat types distributed the habitats into three major groups, with the most similarity occurred between primary and riparian lowland forests (75%). The identification key of the species was made.
Struktur Komunitas Moluska Bentik di Perairan Sekitar PLTU Grati, Pasuruan, Jawa Timur
Authors: Arbi Ucu Yanu
Published: February 2022

Observation on marine benthic molluscs around PLTU Grati waters in Pasuruan was conducted on May and December 2004. The aim of this study was to determine condition and community structure of benthic molluscs living in those areas. Samples were collected using Eckmann grab and sieved through 0.5 mm mesh-sized. The number of molluscs species is 28 species, consisting of 16 species class of gastropoda and 12 species class of pelecypoda. A diversity index (H) ranged 0.845 to 1.158, an evenness index (J) was 0.856 to 1 and a richness index (D) was 19.562 to 31.949. Littorina undulata (Littorinidae) was a dominant species and was relatively widely distributed. In general, this result showed that around PLTU Grati waters had a relatively low benthic molluscs diversity.
Kualitas Yoghurt Sinbiotik Dengan Kombinasi Tepung Kimpul (Xanthosoma sagittifolium) dan Sari Buah Mangga (Mangifera indica var. arumanis)
Authors: F. Sinung Pranata Ngatini Ekawati Purwijantiningsih
Published: February 2022

Yoghurt sinbiotik merupakan yoghurt yang dibuat dengan mengombinasikan probiotik dan prebiotik. Kimpul (Xanthosoma sagittifolium) mengandung senyawa bioaktif diosgenin dan inulin yang digunakan sebagai substrat untuk pertumbuhan probiotik. Mangga (Mangifera indica) mengandung glukosa yang dapat dimanfaatkan untuk pertumbuhan bakteri asam laktat (BAL). Bakteri asam laktat (BAL) yang ditambahkan sebagai starter yakni Lactobacillus acidophilus dan Bifidobacterium longum. Penelitian ini bertujuan mengetahui pengaruh penambahan kombinasi tepung kimpul dan sari buah mangga (K:M) terhadap kualitas fisik, kimia, mikrobiologis, organoleptik dan mendapatkan konsentrasi optimum penambahan kombinasi (K:M) yang menghasilkan kualitas yoghurt sinbiotik yang paling baik. Penelitian ini menggunakan Rancangan Acak Lengkap (RAL) dengan 4 perlakuan kombinasi (K:M) sebanyak 10:4%, 7:7%, 4:10%, dan 0:0% dengan 3 kali ulangan. Variabel yang diamati meliputi warna, viabilitas BAL, salmonella, kadar lemak, protein, serat larut, derajat keasaman (pH), total asam laktat, gula reduksi dan uji organoletik. Data dianalisis dengan ANOVA, dilanjutkan dengan uji Duncan. Hasil penelitian menunjukkan bahwa penambahan (K:M) berpengaruh nyata terhadap peningkatan viabilitas BAL, kadar gula reduksi, derajat keasaman (pH), dan kadar asam laktat. Penambahan kombinasi (K:M) 4:10% menghasilkan kualitas yoghurt sinbiotik yang baik, paling disukai oleh panelis dengan rasa asam, tekstur semisolid, viabilitas BAL 1 x 109 CFU/ml, negatif Salmonella, kadar lemak 1,69%, kadar protein 3,55%, kadar serat larut 2,36%, kadar asam laktat 1,48% dan pH 4.
Endonesia (Endophyte for Indonesia): Biofertilizer Berbasis Mikroba Endofit guna Meningkatkan Kualitas Pembibitan Budidaya Kelapa Sawit (Elaeis guineensis) di Indonesia
Authors: Manguntungi Baso , Asmawati Rian Adha Ardinata Muhammad Al Azhar , Tegar Aprilian1 Kurniawan Eka Putra
Published: February 2022

Indonesia merupakan negara produsen kelapa sawit (Elaeis guineensis) dengan jumlah produksi mencapai 48% dari total volume produksi minyak sawit di dunia. Produksi minyak kelapa sawit Indonesia menunjukkan peningkatan yang stabil selama 20 tahun terakhir yaitu sebesar 11% setiap tahunnya. Proses pembibitan kelapa sawit menjadi faktor penentu dalam keberhasilan perkebunan kelapa sawit. Penggunaan pupuk kimia pada pembibitan kelapa sawit diketahui dapat menimbulkan banyak dampak negatif terhadap lingkungan dan kesehatan manusia. Guna mengatasi permasalahan tersebut, pemanfaatan teknologi mikroba endofit indigen sebagai agen aktif dalam biofertiizer perlu dilakukan. Mikroba endofit adalah mikroba yang hidup didalam jaringan tanaman dan memiliki kemampuan untuk mendorong pertumbuhan tanaman. Penelitian ini bertujuan mendapatkan strain mikroba endofit potensial sebagai agen bioaktif dalam biofertilizer dan pengaruhnya terhadap proses pembibitan kelapa sawit. Analisis data dilakukan dengan uji ANOVA menggunakan aplikasi SPSS 20 dengan taraf kepercayaan 95%. Hasil isolasi mikroba endofit dari akar tanaman kelapa sawit diperoleh 7 isolat jamur endofit dan 9 isolat bakteri endofit. Hasil penelitian menunjukan konsorsium bakteri 20%, konsorsium bakteri 10%, dan konsorsium jamur 10% berturut-turut memiliki pengaruh terhadap peningkatan tinggi tanaman, diameter batang, dan jumlah daun kelapa sawit dibandingkan dengan perlakuan lainnya
Kualitas Pupuk Cair Organik dengan Kombinasi Limbah Ampas Jamu dan Limbah Ikan
Authors: A. Wibowo Nugroho Jati,L. Indah Murwani Yulianti Jumirah
Published: February 2022

Pupuk cair organik merupakan salah satu jenis pupuk organik berbentuk cair yang berfungsi sebagai sumber nutrisi bagi tanaman. Pupuk cair organik dibuat dari bahan organik limbah rumah tangga. Bahan organik yang digunakan dalam penelitian ini adalah limbah ampas jamu dan limbah ikan. Tujuan penelitian ini untuk mengetahui seberapa besar kadar unsur hara karbon (C), nitrogen (N), fosfor (P), kalium (K), kalsium (Ca), besi (Fe), dan magnesium (Mg) yang dibandingkan dengan standar SNI-19-7030-2004 dan Permentan/SR.140/10/2011, serta karakterisasi bakteri yang ada dalam pupuk cair organik. Pembuatan pupuk cair organik dalam penelitian ini menggunakan metode fermentasi secara anaerob selama 28 hari dengan lima perlakuan yaitu 100% limbah ampas jamu; 100% limbah ikan; dan perbandingan limbah ampas jamu dan limbah ikan sebesar 50%:50%; 25%:75% dan 75%;25%. Hasil pengukuran kadar unsur C sebesar 2,3474-4,8397%, unsur N sebesar 0,047-0,3537%, unsur P sebesar 0,0343-0,2433%, unsur K sebesar 0,1867-0,2433%, unsur Ca sebesar 0,0204-0,0777%, kadar Fe sebesar 0,0019-0,0003%, dan kadar Mg sebesar 0,0129-0,02008%. Isolat bakteri yang ditemukan dalam pupuk cair organik yaitu isolat bakteri yang memiliki karakter menyerupai bakteri dari genus Lactobacillus sp., Psudomonas sp., Bacillus sp., Zymomonas sp., Staphylococcus sp., Actinobacillus sp., Cellulomonas sp., dan Acetobacter sp
Pemanfaatan Bakteri Indigenus dalam Reduksi Logam Berat Cu pada Limbah Cair Proses Etching Printed Circuit Board (PCB)
Authors: A. Wibowo Nugroho Jati,L. Indah Murwani Pascalia Shendy Shendy
Published: February 2022

Limbah dari proses etching PCB yang dihasilkan bersifat toksik karena memiliki pH yang sangat rendah dan kandungan logam berat Cu yang tinggi. Dampak negatif dari limbah etching PCB ini yaitu dapat menghilangkan kesuburan tanah, merusak nutrisi tanah dan mencemari air, serta meracuni makhluk hidup sekitar. Dalam penelitian ini, metode biologi digunakan untuk melakukan remediasi limbah proses etching PCB. Bioremediasi limbah proses etching PCB ini dilakukan dalam sistem lumpur aktif. Sumber lumpur aktif berasal dari tanah sawah yang kaya akan massa mikroorganisme. Penelitian ini bertujuan mengetahui efektifitas pengolahan limbah secara biologi dalam mengurangi toksisitas limbah, meliputi pH dan kandungan logam berat Cu, serta mengetahui isolat bakteri yang dapat memperbaiki kualitas limbah cair proses etching PCB. Tahapan penelitian ini meliputi inkubasi limbah selama 7 hari dalam sistem lumpur aktif dengan perlakuan penambahan limbah etching PCB dengan konsentrasi logam Cu 50 ppm, 150 ppm, 250 ppm dan 350 ppm, pengukuran parameter pada hari ke-0 dan ke-7, isolasi bakteri, serta analisis data menggunakan software SPSS ver 15.  Parameter yang diukur adalah kandungan logam berat Cu, pH, TSS, BOD dan COD. Pengukuran logam berat Cu dilakukan menggunakan spektrofotometer direct Lovibond. Setelah 7 hari masa inkubasi, kandungan logam berat Cu, COD, BOD dan TSS mengalami penurunan serta pH mengalami kenaikan. Perlakuan  A (50 ppm) mengalami penurunan kadar logam Cu yang paling tinggi yaitu sebesar 93,18%, diikuti dengan perlakuan B (150 ppm) dengan penurunan sebesar 81,94%, perlakuan D (350 ppm) dengan penurunan sebesar 31,57% dan perlakuan C (250 ppm) dengan penurunan sebesar 18,09%. Terdapat tiga bakteri indigenus hasil isolasi bakteri yaitu isolat bakteri X, Y dan Z. Hasil karakterisasi bakteri menunjukkan bahwa isolat X, Y, dan Z memiliki bentuk koloni circular, tepi koloni entire, Gram negatif, motil, katalase positif dan indol positif.
Toksisitas Akut Ekstrak Albertisia papuana Becc. pada Daphnia magna dan Danio rerio
Authors: Marihot Pasaribu,Sjarif Ismail Hary Nugroho,
Published: February 2022

Albertisia papuana Becc. (A. papuana) digunakan oleh etnis Dayak di Kaltim sebagai obat antihipertensi, antiinfeksi, anti demam, dan bumbu masak pengganti vetsin. Belum adanya data mengenai toksisitas akut pada Albertisia papuana Becc. (A. papuana) menyebabkan perlunya uji toksisitas akut. Tujuan dari peneltian ini adalah untuk mengetahui toksisitas akut pada ekstrak daun A. papuana dengan uji imobilisasi Daphnia magna (D. magna) dan uji toksisitas akut Danio rerio (D. rerio). Metode: Daun A. papuana diambil dari Kabupaten Kutai Kartanegara, Provinsi Kalimantan Timur. Ekstraksi dilakukan secara maserasi dengan pelarut etanol. Uji imobilisasi D. magna dan uji toksisitas akut D. rerio dilakukan dengan  metode OECD (Organisation for Economic Co-operation and Development). Hasil yang didapatkan adalah nilai Lethal Concentration 50 (LC50) ekstrak pada D. magna adalah (170 + 28) mg/L untuk 24 jam dan (45 + 9) mg/L untuk 48 jam.Nilai LC50 ekstrak pada D. rerio adalah (885 + 55) mg/L untuk 24 jam, (670 + 94) mg/L untuk 48 jam, (504 + 102) mg/L untuk 72 jam, dan (393+89) mg/L untuk 96 jam. Simpulan yang diperoleh dari penelitian ini adalah ekstrak etanol A. papuana sedikit toksik pada D. magna sedangkan pada D. rerio dewasa bersifat tidak toksik
Effect of the Type of Organic Waste and Retention Time on Biogas Production from Cow Dung
Authors: Mago Oktavius Yoseph Tuta , Nirmalasari M A Yohanita , Kuki Agustina Dua , Bunga Yohanes Nong , Misa Aljefridus
Published: February 2022

Nowadays, the demand on fossil energy is increasing in number whereas its availability is decrease. People are still reckoned on it, despite of its rareness. Fossil energy utilized must be banned due to its negative effect. It is time for us to use renewable and eco-friendly energy (biofuel). Biogas is one of biofuel produced from anaerobic decomposition of organic matter by microorganisms. Organic waste as a by-product of our daily activities can be used as raw material to produce biogas. To use waste, means to decrease the environmental pollution problem. This research is aim to study the type of organic waste as a raw material to produce biogas through anaerobic digestion and its retention time. Organic wastes that were used in this research are domestic waste (food waste), agriculture waste (corn leaves) and industrial waste (solid and liquid waste of tofu). All of these wastes were mixed with cow dung as the starter/inoculum. As a control, the starter was used without organic waste addition. The testable retention times were 1st week until 9th week. The experimental design was Factorial Complete Randomized Design with confidence level 95%. The result showed that all the type of organic waste can be used to produce biogas through anaerobic digestion. Statistically, the average volume of biogas produced from industrial waste per week, 5794,3 ml was significantly different from any other organic waste (P=0,000). The best retention time was found on 8th week with the average volume of biogas was 3675,6 ml (P=0,006). There was no interaction between these two factors (P=0,1). This research is expected to open the people’s awareness about the management of useable organic waste as a raw material to produce biogas.
Isolasi dan Karakterisasi Amilase dari Kapang Alkalotoleran Asal Limbah Cair Tapioka
Authors: Mubarik Nisa Rachmania , Damayanti Evi , Listyowati Sri
Published: February 2022

A total of 6 fungi isolates of growing at pH 9 and 2 isolates on pH 10 with amylolytic indexes 0f 0.07-1.42 have been isolated from cassava starch liquid waste. Two isolates having the highest amylolytic index were identified as Aspergillus sydowii K10 (1.42) and Aspergillus versicolor L30 (1.4). Both A. sydowii K10 and A. versicolor L30 were described as alcalotolerant for being able to grow with range pH 5-10. The optimal -amylases production of A. sydowii K10 and A. versicolor L30 was obtained after 4 and 3 days of incubation at 300C. The optimum of -amylase activity from A. sydowii K10 was at 400C and 700C, and pH 6; while those from A. versicolor L30 was at 500C and pH 6 respectively. Both A. sydowii K10 and A. versicolor L30 could produce glucoamylase. The optimum of glucoamylase activity from A. sydowii K10 was at 400C and pH 5, while those from A. versicolor L30 was at 500C and pH 5 respectively.
Keanekaragaman Flora di Hutan Mangrove Kawasan Pesisir Teluk Mandar, Polewali, Propinsi Sulawesi Selatan: Kajian Pendahuluan
Authors: Pramudji Pramudji
Published: February 2022

The sudy of mangrove forest in the coastal zone of Mandar Bay, Polewali, Province of South Sulawesi was carried out from  July 21st to July 28th  2002. Data was collected from 5 locations (Panampeang Island, Battuwai Island, Salamah Island, Koremasang Island, and coastal zone of Binnuang) following transect method.  The result showed that mangrove in the coastal zone of Mandar Bay was dominated by Rhizophora  stylosa and Sonneratia alba. The floristic composition of mangrove forest consist of 29 species. Recently, the extent of mangrove forest in this area was decreasing due to the conversion of mangrove into human settlement, fishpond and uncontrolled mangrove exploitation. This situation lead to the depletion of the living organisms, which are living in this area.
Penetapan Tingkat Eksploitasi dan Status Populasi Kura-kura Hutan Sulawesi (Leucocephalon yuwonoi McCord, Iverson and Boeadi, 1995) di Kawasan Sulawesi Tengah Bagian Utara, Indonesia
Authors: Riyanto Awal
Published: February 2022

Kura-kura Sulawesi (Leucocephalon yuwonoi McCord, Iverson and Boeadi, 1995) adalah satu dari sekian banyak kura-kura yang paling sedikit diketahui dan paling jarang di dunia. Pada tahun 1995 yaitu tahun pertama ditemukan, kura-kura ini telah membanjiri restoran di daratan utama Cina, dan oleh IUCN-The World Conservation Union  populasi kura-kura  ini dikategorikan kritis. Penelitian ini untuk mengungkap tingkat eksploitasi dan status kura-kura Sulawesi yang dilakukan di kawasan utara Sulawesi Tengah dari tanggal 28 April sanpai 13 Mei 2002. Penelitian dilakukan dengan dua pendekatan yaitu (1) survei menggunakan garis transek pada habitat yang merupakan kawasan anak sungai dan (2) kunjungan kepada para pemburuh atau kolektor untuk mendata jumlah kura-kura yang ditangkap. Hasil penelitian ini menunjukkan bahwa tingkat eksploitasi kura-kura Sulawesi pada tahun 2002 diperkirakan mencapai 720 ekor dan status populasinya dinyatakan langka dengan frekuensi 1,91 per hari. Hasil penelitian  berhasil pula mengungkapkan lokasi baru pada  penyebaran kura-kura Sulawesi.
Microcontroller Systems in Education for Sustainable Development Service. A Qualitative Thematic Meta-Analysis
Authors: Savelidi Maria , Savelides Socrates , Georgousis Efthymios , Papadopoulou Georgia , Fasouraki Rigo , Drinia Hara
Published: February 2022

Goal of the present paper is to answer the research question: Can the proper use of Microcontroller Board |Systems as educational tools help achieve the goals of Education for Sustainable Development? In order to answer the aforementioned question, a meta-analysis of the qualitative strategy of four recently published relevant papers was utilized. The technique of Thematic Analysis was used. The results show that the proper adaptation of Microcontroller Board Systems in the educational process can adequately help achieve the goals of the Education for Sustainable Development. In order to achieve these goals in the pedagogical framework, the Microcontroller System can be adapted in such a way as to serve the approaches of holistic & systemic thinking, HASS&STEM interdisciplinarity and multidisciplinarity, constructivist approach to knowledge, cooperative learning, critical thinking, cultivation of values, and learning satisfaction of the Education for Sustainable Development.
Student-Teachers’ Abilities and Attitudes towards Scratch as a Multimedia Construction tool to Represent Physical Geography Phenomena
Authors: Stoumpa Artemisia , Skordoulis Dionisios , Galani Apostolia (Lia)
Published: February 2022

The aim of this paper is to describe a didactic intervention that aimed to introduce pre-service teachers to visual programming with the ultimate goal of enabling them to support their students on constructing multimedia in the context of Geography in the future. Students created multimedia software about Physical Geography topics using MIT Scratch. The way the students used scientific knowledge and did the didactic transformation in order to build their artefacts has been presented elsewhere. In this article students’ ability and attitudes on programming are examined. More specifically, we study the techniques and programming structures students use, as an indicator of what students learned. Furthermore, we study difficulties on programming and other technical difficulties they confront, as well as their attitudes towards Scratch which developed through the didactic intervention. The results are encouraging since students create software that work properly and develop a positive attitude toward Scratch.