bluuebunny/crossref_metadata_2025_split huggingface dataset:
Perceptual Decision-Making: Biases in Post-Error Reaction Times Explained by Attractor Network Dynamics
Authors: Berlemont Kevin , Nadal Jean-Pierre 
Published: November 2018

Perceptual decision-making is the subject of many experimental and theoretical studies. Most modeling analyses are based on statistical processes of accumulation of evidence. In contrast, very few works confront attractor network models' predictions with empirical data from continuous sequences of trials. Recently however, numerical simulations of a biophysical competitive attractor network model have shown that such a network can describe sequences of decision trials and reproduce repetition biases observed in perceptual decision experiments. Here we get more insights into such effects by considering an extension of the reduced attractor network model of Wong and Wang (2006), taking into account an inhibitory current delivered to the network once a decision has been made. We make explicit the conditions on this inhibitory input for which the network can perform a succession of trials, without being either trapped in the first reached attractor, or losing all memory of the past dynamics. We study in detail how, during a sequence of decision trials, reaction times and performance depend on nonlinear dynamics of the network, and we confront the model behavior with empirical findings on sequential effects. Here we show that, quite remarkably, the network exhibits, qualitatively and with the correct order of magnitude, post-error slowing and post-error improvement in accuracy, two subtle effects reported in behavioral experiments in the absence of any feedback about the correctness of the decision. Our work thus provides evidence that such effects result from intrinsic properties of the nonlinear neural dynamics.SIGNIFICANCE STATEMENTMuch experimental and theoretical work is being devoted to the understanding of the neural correlates of perceptual decision-making. In a typical behavioral experiment, animals or humans perform a continuous series of binary discrimination tasks. To model such experiments, we consider a biophysical decision-making attractor neural network, taking into account an inhibitory current delivered to the network once a decision is made. Here we provide evidence that the same intrinsic properties of the nonlinear network dynamics underpins various sequential effects reported in experiments. Quite remarkably, in the absence of feedback on the correctness of the decisions, the network exhibits post-error slowing (longer reaction times after error trials) and post-error improvement in accuracy (smaller error rates after error trials).
A Posterior–Anterior Distinction between Scene Perception and Scene Construction in Human Medial Parietal Cortex
Authors: Silson Edward H. , Gilmore Adrian W. , Kalinowski Sarah E. , Steel Adam , Kidder Alexis , Martin Alex , Baker Chris I. 
Published: November 2018

Human retrosplenial complex (RSC), located in medial parietal cortex, has been implicated in numerous cognitive functions, including scene perception, spatial navigation, and autobiographical memory retrieval. Recently, a posterior–anterior distinction within RSC was proposed, such that posterior aspects process scene-related visual information (constituting a medial place area [MPA]), whereas anterior aspects process information that is vividly retrieved from memory, thereby supporting remembering and potentially navigation. Here, we tested this proposed distinction in a single group of participants (both male and female) using fMRI with both perceptual and mnemonic tasks. After completing a resting-state scan, participants performed a task that required constructing scenes from memory and completed a scene selectivity localizer task. We tested directly perceptual and mnemonic responses in MPA and an anterior, connectivity-defined region (CON), which showed strong functional connectivity with anterior parahippocampal place area. A double dissociation was observed, such that CON was more strongly activated during scene construction than was MPA, whereas MPA was more perceptually responsive than CON. Further, peak responses from the scene construction task were anterior to perceptual peaks in all but 1 participant and hemisphere. Finally, through analyses of the posterior–anterior response profiles, we identify the fundus of the parieto-occipital sulcus as a potential location for the crossover from perceptual to mnemonic representations and highlight a potential left-hemisphere advantage for mnemonic representations. Collectively, our results support a distinction between posterior and anterior aspects of the RSC, suggesting that more specific functional-anatomic terms should be used in its place in future work.SIGNIFICANCE STATEMENTThe retrosplenial complex (RSC) has been implicated in vision, spatial cognition, and memory. We previously speculated on a potential posterior–anterior distinction within RSC for scene perception and memory-based scene construction/navigation. Here, we tested this distinction through a combination of resting-state, perceptual, and mnemonic task data. Consistent with our predictions, we demonstrate that perceptual responses peak consistently posterior of those elicited by memory-based scene construction within the broader RSC. Further, we highlight (1) the fundus of the parieto-occipital sulcus as a landmark for the transition between these representations, (2) the anterior bank of parieto-occipital sulcus as the point of maximal separation between these representations, and (3) identify a potential hemispheric asymmetry in mnemonic representations. These data support functional dissociations within RSC.
Fine Control of Sound Frequency Tuning and Frequency Discrimination Acuity by Synaptic Zinc Signaling in Mouse Auditory Cortex
Authors: Kumar Manoj , Xiong Shanshan , Tzounopoulos Thanos , Anderson Charles T. 
Published: November 2018

Neurons in the auditory cortex are tuned to specific ranges of sound frequencies. Although the cellular and network mechanisms underlying neuronal sound frequency selectivity are well studied and reflect the interplay of thalamocortical and intracortical excitatory inputs and further refinement by cortical inhibition, the precise synaptic signaling mechanisms remain less understood. To gain further understanding on these mechanisms and their effects on sound-driven behavior, we usedin vivoimaging as well as behavioral approaches in awake and behaving female and male mice. We discovered that synaptic zinc, a modulator of neurotransmission and responsiveness to sound, sharpened the sound frequency tuning of principal and parvalbumin-expressing neurons and widened the sound frequency tuning of somatostatin-expressing inhibitory neurons in layer 2/3 of the primary auditory cortex. In the absence of cortical synaptic zinc, mice exhibited reduced acuity for detecting changes in sound frequencies. Together, our results reveal that cell-type-specific effects of zinc contribute to cortical sound frequency tuning and enhance acuity for sound frequency discrimination.SIGNIFICANCE STATEMENTNeuronal tuning to specific features of sensory stimuli is a fundamental property of cortical sensory processing that advantageously supports behavior. Despite the established roles of synaptic thalamocortical and intracortical excitation and inhibition in cortical tuning, the precise synaptic signaling mechanisms remain unknown. Here, we investigated these mechanisms in the mouse auditory cortex. We discovered a previously unknown signaling mechanism linking synaptic zinc signaling with cell-specific cortical tuning and enhancement in sound frequency discrimination acuity. Given the abundance of synaptic zinc in all sensory cortices, this newly discovered interaction between synaptic zinc and cortical tuning can provide a general mechanism for modulating neuronal stimulus specificity and sensory-driven behavior.
Tekanan Panas, Konsumsi Cairan, dan Penggunaan Pakaian Kerja dengan Tingkat Dehidrasi
Authors: Ariyanti Sheila Mufida , Setyaningsih Yuliani , Prasetio Diki Bima 
Published: November 2018

Abstrak
Pekerja di lingkungan panas dapat terpapar dehidrasi. Selain lingkungan kerja yang panas dehidrasi dapat disebabkan oleh kurangnya konsumsi cairan, penggunaan pakaian saat bekerja dan riwayat penyakit yang dimiliki.Pekerja pandai besi Desa Hadipolo terpapar panas dari lingkungan kerja berkisar antara 30oC –35oC dan mengalami tanda-tanda dehidrasi. Penelitian dilaksanakan pada tanggal 7-15 April 2018.Tujuan penelitian menganalisis hubungan tekanan panas, konsumsi cairan dan penggunaan pakaian saat bekerja dengan tingkat dehidrasi pada pekerja pandai besi di Desa Hadipolo Kecamatan Jekulo Kabupaten Kudus. Penelitian ini merupakan penelitian analitik observasional dengan pendekatan cross sectional. Hasil penelitian ini ada hubungan antara tekanan panas (p value = 0,036), konsumsi cairan (p value = 0,021), penggunaan pakaian saat bekerja (p value = 0,020) dengan tingkat dehidrasi. Analisis secara multivariat diperoleh hasil kategori konsumsi cairan dengan p value = 0,016 dan kategori penggunaan pakaian saat bekerja dengan p value = 0,017. Kesimpulan dari penelitian ini variabel yang paling berperan terhadap tingkat dehidrasi yaitu kategori konsumsi cairan kategori dan penggunaan pakaian saat bekerja.

Abstract
Workers in hot environments can be exposed to dehydration. In addition to a hot dehydrated work environment, it can be caused by a lack of fluid consumption, the use of clothing at work and the history of the disease. Blacksmith workers in Hadipolo village are exposed to heat from the work environment ranging from 30oC -35oC and experiencing signs of dehydration. The study was conducted on April 7-15, 2018. The purpose of the study was to analyze the relationship between heat stress, fluid consumption and clothing usage while working with the level of dehydration in blacksmith workers in Hadipolo Village, Jekulo District, Kudus Regency. this research is an observational analytic study with cross sectional approach. The results of this study there is a relationship between heat stress (p value = 0.036), fluid consumption (p value = 0.021), use of clothing at work (p value = 0.020) with the level of dehydration with. Multivariate analysis obtained results of fluid consumption category with p value = 0.016 and clothing usage category while working with p value = 0.017. The conclusion of this study is the variable that most plays a role in the level of dehydration, namely the category of consumption of liquid and clothing usage category while working
SNZ3 Encodes a PLP Synthase Involved in Thiamine Synthesis in Saccharomyces cerevisiae
Authors: Paxhia Michael D , Downs Diana M 
Published: November 2018

Abstract
Pyridoxal 5′-phosphate (the active form of vitamin B6) is a cofactor that is important for a broad number of biochemical reactions and is essential for all forms of life. Organisms that can synthesize pyridoxal 5′-phosphate use either the deoxyxylulose phosphate-dependent or -independent pathway, the latter is encoded by a two-component pyridoxal 5′-phosphate synthase. Saccharomyces cerevisiae contains three paralogs of the two-component SNZ/SNO pyridoxal 5′-phosphate synthase. Past work identified the biochemical activity of Snz1p, Sno1p and provided in vivo data that SNZ1 was involved in pyridoxal 5′-phosphate biosynthesis. Snz2p and Snz3p were considered redundant isozymes and no growth condition requiring their activity was reported. Genetic data herein showed that either SNZ2 or SNZ3 are required for efficient thiamine biosynthesis in Saccharomyces cerevisiae. Further, SNZ2 or SNZ3 alone could satisfy the cellular requirement for pyridoxal 5′-phosphate (and thiamine), while SNZ1 was sufficient for pyridoxal 5′-phosphate synthesis only if thiamine was provided. qRT-PCR analysis determined that SNZ2,3 are repressed ten-fold by the presence thiamine. In total, the data were consistent with a requirement for PLP in thiamine synthesis, perhaps in the Thi5p enzyme, that could only be satisfied by SNZ2 or SNZ3. Additional data showed that Snz3p is a pyridoxal 5′-phosphate synthase in vitro and is sufficient to satisfy the pyridoxal 5′-phosphate requirement in Salmonella enterica when the medium has excess ammonia.
Strategies for Efficient Genome Editing Using CRISPR-Cas9
Authors: Farboud Behnom , Severson Aaron F , Meyer Barbara J 
Published: November 2018

AbstractThe targetable DNA endonuclease CRISPR-Cas9 has transformed analysis of biological processes by enabling robust genome editing in model and nonmodel organisms. Although rules directing Cas9 to its target DNA via a guide RNA are straightforward, wide variation occurs in editing efficiency and repair outcomes for both imprecise error-prone repair and precise templated repair. We found that imprecise and precise DNA repair from double-strand breaks (DSBs) is asymmetric, favoring repair in one direction. Using this knowledge, we designed RNA guides and repair templates that increased the frequency of imprecise insertions and deletions and greatly enhanced precise insertion of point mutations in Caenorhabditis elegans. We also devised strategies to insert long (10 kb) exogenous sequences and incorporate multiple nucleotide substitutions at a considerable distance from DSBs. We expanded the repertoire of co-conversion markers appropriate for diverse nematode species. These selectable markers enable rapid identification of Cas9-edited animals also likely to carry edits in desired targets. Lastly, we explored the timing, location, frequency, sex dependence, and categories of DSB repair events by developing loci with allele-specific Cas9 targets that can be contributed during mating from either male or hermaphrodite germ cells. We found a striking difference in editing efficiency between maternally and paternally contributed genomes. Furthermore, imprecise repair and precise repair from exogenous repair templates occur with high frequency before and after fertilization. Our strategies enhance Cas9-targeting efficiency, lend insight into the timing and mechanisms of DSB repair, and establish guidelines for achieving predictable precise and imprecise repair outcomes with high frequency.
Pembentukan Hidrogen dari Air Secara Fotokatalitik oleh Serbuk TiO2 yang Didoping Nitrogen
Authors: Arfi Febrina , Aziz Hermansyah , Alif Admin 
Published: November 2018

Abstrak Kesadaran terhadap ancaman krisis energi karena kebutuhan yang sangat besar dan pencemaran lingkungan yang terjadi, maka perlu dilakukan penelitian untuk menghasilkan sumber energi alternatif. Hidrogen merupakan energi alternatif yang dapat digunakan sebagai bahan bakar, ramah lingkungan, dan dihasilkan dari sumber yang melimpah di bumi yaitu air. Salah satu metode yang dipakai untuk memproduksi gas hidrogen adalah metode fotolisis. Katalis yang digunakan adalah TiO2 yang didoping N, tujuannya mempelajari pengaruh variasi perbandingan TiO2/N terhadap aktifitas fotokatalitik pembentukan hidrogen. Hasil penelitian memperlihatkan produksi gas menggunakan TiO2/N pada kondisi optimum terjadi pada perbandingan 4:6 yang menghasilkan gas 2.2 mL. Dari hasil penelitian dapat disimpulkan bahwa TiO2 doping N dapat membantu pembentukan gas secara fotokatalitik. Kata kunci : Fotolisis, katalis, doping, fotokatalitik Abstract The awareness about energy crisis is rising quickly. Consider to the very fast growing need of energy and the environmental impact caused by the conventional energy, so that the research about renewable energy as an alternative energy resource is very urgent. Therefore, the research to produce hydrogen as an alternative energy resourse was conducted. Hydrogen can be used as a green fuel which can be extracted from water, a huge amount of resource on the earth. In this research, the photolysis method was used. Nitrogen-doped TiO2 catalyst was used in order to analyse the influence of variational ratio of TiO2/N to the photocatalytic process of hydrogen production. The result shows that the optimum condition in producing gas using TiO2/N occured at the ratio 4:3 which produced as much as 2.2 ml gas. From this result can be concluded that Nitrogen-doped TiO2 supports the extraction of gas in photocatalytic process. Keywords: Photolysis, catalys, doped, photocatalytic DOI: http://dx.doi.org/10.15408/jkv.v0i0.3077
Analisis Karaterisasi Konsentrasi dan Komposisi Partikulat Udara (Studi Case : Surabaya)
Authors: Ahmad Eka Fithriani , Santoso Muhayatun 
Published: November 2018

Abstrak Pencemaran udara merupakan dampak yang sangat merugikan, tidak hanya bagi manusia tetapi juga akan berdampak buruk bagi ekosistem hewan dan tumbuhan. Pada penelitian ini akan mengkaji pencemaran udara dari Oktober 2012 hingga Februari 2014 melalui penelitian konsentrasi dan komposisi dari partikulat udara dengan ukuran PM 2.5. Penelitian ini bertujuan untuk menentuan sumber asal pencemaran di Surabaya sehingga dapat dijadikan referensi berbasis ilmiah sebagai langkah untuk membuat keputusan dan kebijakan yang tepat dalam menanggulangi dampak pencemaran. Metode pengolahan data dalam penelitian ini adalah dengan menggunakan analisis reseptor modeling yaitu Positif Matrix Factorization (PMF) untuk mengetahui sumber asal pencemaran. Hasil pengukuran yang diperoleh pada konsentrasi PM 2,5 adalah 15.05 μg/m3 sehingga telah melebihi baku mutu tahunan yang telah ditetapkan PP 41 tahun 1999, USEPA, maupun WHO. Dalam partikulat terdapat konsentrasi black carbon (BC) sebesar 3.20 μg/m3 dan unsur Pb dengan konsentrasi 0.28 μg/m3 yang telah melebihi nilai baku mutu USEPA. Sedangkan hasil analisis reseptor modeling di dapatkan sumber asal polutan berasal dari biomass, vehicle, soil, industri Pb, industri Zn dan indutri Fe. Kata kunci: Partikulat mater 2.5, black carbon, Pb, positive matrix factorization, Surabaya Abstract Air pollution is a very adverse impact, not only for humans but also the ecosystem of plants and animals. This research examine air pollution from October 2012 until February 2014 through the research of concentration and composition of airborne particulates with a size of PM 2.5 μm. This study aims to determine the origin and location of pollution sources in Surabaya so that it can be used as scientific reference as a step to make the right decisions and policies in tackling the impact of pollution. Data processing method in this research used analysis of receptor modeling that is Positive Matrix Factorization (PMF) to determine the source of the pollution. Results obtained at a concentration of PM 2.5 was 15.05 μg/m3 so PM 2.5 has exceeded the quality standard yearly, based on PP 41 1999, USEPA and WHO. There are 3.20 μg/m3 concentration of black carbon (BC), element Pb in particulate matter with a concentration of 0.28 μg/m3 which has exceeded the value of the quality standard USEPA. The source of the pollutants come from biomass, vehicle, soil, industrial Pb, Zn and industries Fe industry. Keywords: Particulate matter 2.5, black carbon, Pb, positive matrix factorization, Surabaya DOI: http://dx.doi.org/10.15408/jkv.v0i0.3602
Solid-phase Synthesis of Tetrapeptide on 2-Chlorotrityl Chloride Resin by Using Benzotriazol-1-yl-oxytripyrrolidinophosphonium Hexafluorophosphate as Coupling Reagent
Authors: Maharani Rani , Ammatillah Nuruzzahra , Gunawan Gunawan , Hidayat Ace Tatang 
Published: November 2018

Tetrapeptide, OH-Pro-Ala-Gly-Tyr-NH2, was successfully synthesised on 2-chlorotrityl chloride resin by taking advantage of PyBOP (benzotriazol-1-yl-oxytripyrrolidinophosphonium hexafluorophosphate) as coupling reagent. The selection of the peptide as the target of synthesis was due to its interesting bioactivity as antioxidant. The synthesis was undertaken with Fmoc strategy, where Fmoc-proline was added onto the resin at the first place. It is known from the literature that proline can resist from rasemisation when it was attached on the resin at the first time. Fmoc deprotection step was carried out by employing 20% piperidine in DMF and the reaction mixture was shaken for 30 minutes. Once the proline attached, the next step was to attach amino acids, alanine (Ala), glycine (Gly) and tyrosine(Tyr), subsequently onto the resin until tetrapeptidyl resin was constructed on the resin. Hydroxyl group of Tyr was protected with t-butyl, which is TFA-labiled. Coupling reaction was undertaken by mixing the amino acid and PyBOP in a mixture of dichloromethane and DMF (1:1) and in the presence of basic DIPEA. Resin cleavage step was carried out by using 95% TFA in water, where t-butyl protecting group on the side chain of Tyr was cleaved at the same time. The analytical RP-HPLC of the final product showed a single peak at 21.9 minutes (20-90% of acetonitrile in water with 0.1% of TFA during 30 minutes), indicating that each coupling has given a good coupling performance and resulting in a pure product. The desired product showed the correct molecular weight with m/z 407.2 [M+H]+ and 429.2 [M+Na]. DOI: http://dx.doi.org/10.15408/jkv.v0i0.4055
Poriferasta-5,22E,25-trien-3β-ol,22-dehidrokolesterol dari daun Kalanchoe serrata (Crassulaceae)
Authors: Abdullah Fajar Fauzi , Nandiwardhana Satwika , Hakim Arif Rahman , Herlina Tati , Supratman Unang 
Published: November 2018

Dalam penelitian berkelanjutan untuk pencarian senyawa metabolit sekunder baru dari tumbuhan Kalanchoe Indonesia, telah dilakukan kajian fitokimia terhadap Kalanchoe serrata. Daun segar K. serrata sebanyak 14,8 kg diekstraksi dengan metanol pada temperatur kamar. Ekstrak metanol (292 g) dipartisi berturut-turut dengan n-heksana dan metilenklorida. Ekstrak metilenklorida (0,80 g) selanjutnya dipisahkan pada kromatografi cair vakum pada silika gel G60 dengan eluen kloroform-aseton yang meningkat kepolarannya sehingga dihasilkan 10 fraksi yang dikelompokan berdasarkan analisis KLT. Padatan yang diperoleh pada fraksi yang terelusi dengan 20% aseton selanjutnya dipisahkan pada kromatografi kolom pada silika gel (230-400 mesh) dengan eluen kloroform dan dimurnikan lebih lanjut dengan kristalisasi pada aseton sehingga dihasilkan isolat berbentuk kristal jarum tak-berwarna sebanyak 23 mg. Isolat menunjukkan titik leleh 115-118oC dan memberikan warna hijau-kebiruan pada uji Liebermann-Burchard menunjukkan adanya kerangka steroid. Hasil analisis spektroskopi yang meliputi UV, IR, 1D-NMR dan 2D-NMR menunjukan bahwa isolat merupakan turunan sterol dan diidentifikasi sebagai poriferasta-5,22E,25-trien-3β-ol,22-dehidrokolesterol.
Profil Fraksi Sitotoksik terhadap Sel Murine Leukemia P-388 dari Ekstrak Biji Honje (Etlingera elatior)
Authors: Rusanti Alfindah , Sukandar Dede , Rudiana Tarso , Adawiah Adawiah 
Published: November 2018

The research characterization of cytotoxic fraction against P-388 leukemia murine cells from the extract honje (Etlingera elatior) seed have been reported. This research lead to isolated and characterization of cytotoxic compounds against P-388 leukemia murine cells from the extract E. elantior seed. The extract of E. elantior seed was maserated by methanol, n-hexane, and ethyl acetate, respectively and estimated their cytotoxic activity against P-388 leukemia murine cell with 3- (4, 5-dimetiltiazol-2-yl) -2,5-difeniltetrazolium bromide (MTT) assay guided toxicity test against of shrimp Artemia salina Leach. Brine shirmp Lethality Test (BSLT) method. The active extracts will be separated by fractionation using column chromatography, radial chromatography, and for analyzing the purity of isolate will estimate by HPLC. The chemical structure of pure isolate will be identified by spectroscopies data UV Vis, FTIR, NMR and MS. The ethyl acetate extract from honje seed have cytotoxic activity by leukemia P-388 cell with IC50 19.21 µg/mL. The compound toxic as cytotoxicagainst P-388 leukemia murine cells is flavonoid compouds their is resveratrol, lapachol, apigenin, methylated chrysin, 6,2’-dihydroxyflavanone, 3-hydroxy-3,4’-dymethoxyflavone and 4’-hydroxy-5,7-dimethoxyflavanone.DOI: http://dx.doi.org/10.15408/jkv.v0i0.3640