bluuebunny/crossref_metadata_2025 huggingface dataset:
Non-genotoxic carcinogen exposure induces defined changes in the 5-hydroxymethylome
Authors: Thomson John P , Lempiäinen Harri , Hackett Jamie A , Nestor Colm E , Müller Arne , Bolognani Federico , Oakeley Edward J , Schübeler Dirk , Terranova Rémi , Reinhardt Diana , Moggs Jonathan G , Meehan Richard R
Published: October 2012

Background

Induction and promotion of liver cancer by exposure to non-genotoxic carcinogens coincides with epigenetic perturbations, including specific changes in DNA methylation. Here we investigate the genome-wide dynamics of 5-hydroxymethylcytosine (5hmC) as a likely intermediate of 5-methylcytosine (5mC) demethylation in a DNA methylation reprogramming pathway. We use a rodent model of non-genotoxic carcinogen exposure using the drug phenobarbital.

Results

Exposure to phenobarbital results in dynamic and reciprocal changes to the 5mC/5hmC patterns over the promoter regions of a cohort of genes that are transcriptionally upregulated. This reprogramming of 5mC/5hmC coincides with characteristic changes in the histone marks H3K4me2, H3K27me3 and H3K36me3. Quantitative analysis of phenobarbital-induced genes that are involved in xenobiotic metabolism reveals that both DNA modifications are lost at the transcription start site, while there is a reciprocal relationship between increasing levels of 5hmC and loss of 5mC at regions immediately adjacent to core promoters.

Conclusions

Collectively, these experiments support the hypothesis that 5hmC is a potential intermediate in a demethylation pathway and reveal precise perturbations of the mouse liver DNA methylome and hydroxymethylome upon exposure to a rodent hepatocarcinogen.
Contribution of the epigenetic mark H3K27me3 to functional divergence after whole genome duplication in Arabidopsis
Authors: Berke Lidija , Sanchez-Perez Gabino F , Snel Berend
Published: October 2012

Background

Following gene duplication, retained paralogs undergo functional divergence, which is reflected in changes in DNA sequence and expression patterns. The extent of divergence is influenced by several factors, including protein function. We examine whether an epigenetic modification, trimethylation of histone H3 at lysine 27 (H3K27me3), could be a factor in the evolution of expression patterns after gene duplication. Whereas in animals this repressive mark for transcription is deposited on long regions of DNA, in plants its localization is gene-specific. Because of this and a well-annotated recent whole-genome duplication, Arabidopsis thaliana is uniquely suited for studying the potential association of H3K27me3 with the evolutionary fate of genes.

Results

Paralogous pairs with H3K27me3 show the highest coding sequence divergence, which can be explained by their low expression levels. Interestingly, they also show the highest similarity in expression patterns and upstream regulatory regions, while paralogous pairs where only one gene is an H3K27me3 target show the highest divergence in expression patterns and upstream regulatory sequence. These trends in divergence of expression and upstream regions are especially pronounced for transcription factors.

Conclusions

After duplication, a histone modification can be associated with a particular fate of paralogs: H3K27me3 is linked to lower expression divergence yet higher coding sequence divergence. Our results show that H3K27me3 constrains expression divergence after duplication. Moreover, its association with higher conservation of upstream regions provides a potential mechanism for the conserved H3K27me3 targeting of the paralogs.
Genome-wide promoter methylation analysis in neuroblastoma identifies prognostic methylation biomarkers
Authors: Decock Anneleen , Ongenaert Maté , Hoebeeck Jasmien , De Preter Katleen , Van Peer Gert , Van Criekinge Wim , Ladenstein Ruth , Schulte Johannes H , Noguera Rosa , Stallings Raymond L , Van Damme An , Laureys Geneviève , Vermeulen Joëlle , Van Maerken Tom , Speleman Frank , Vandesompele Jo
Published: October 2012

Background

Accurate outcome prediction in neuroblastoma, which is necessary to enable the optimal choice of risk-related therapy, remains a challenge. To improve neuroblastoma patient stratification, this study aimed to identify prognostic tumor DNA methylation biomarkers.

Results

To identify genes silenced by promoter methylation, we first applied two independent genome-wide methylation screening methodologies to eight neuroblastoma cell lines. Specifically, we used re-expression profiling upon 5-aza-2'-deoxycytidine (DAC) treatment and massively parallel sequencing after capturing with a methyl-CpG-binding domain (MBD-seq). Putative methylation markers were selected from DAC-upregulated genes through a literature search and an upfront methylation-specific PCR on 20 primary neuroblastoma tumors, as well as through MBD- seq in combination with publicly available neuroblastoma tumor gene expression data. This yielded 43 candidate biomarkers that were subsequently tested by high-throughput methylation-specific PCR on an independent cohort of 89 primary neuroblastoma tumors that had been selected for risk classification and survival. Based on this analysis, methylation of KRT19, FAS, PRPH, CNR1, QPCT, HIST1H3C, ACSS3 and GRB10 was found to be associated with at least one of the classical risk factors, namely age, stage or MYCN status. Importantly, HIST1H3C and GNAS methylation was associated with overall and/or event-free survival.

Conclusions

This study combines two genome-wide methylation discovery methodologies and is the most extensive validation study in neuroblastoma performed thus far. We identified several novel prognostic DNA methylation markers and provide a basis for the development of a DNA methylation-based prognostic classifier in neuroblastoma.
Markups and Firm-Level Export Status
Authors: Loecker Jan De , Warzynski Frederic
Published: October 2012

In this paper, we develop a method to estimate markups using plant-level production data. Our approach relies on cost-minimizing producers and the existence of at least one variable input of production. The suggested empirical framework relies on the estimation of a production function and provides estimates of plant-level mark-ups without specifying how firms compete in the product market. We rely on our method to explore the relationship between markups and export behavior. We find that markups are estimated significantly higher when controlling for unobserved productivity; that exporters charge, on average, higher markups and that markups increase upon export entry. (JEL D22, D24, F14, L11, L60)
The Contribution of Large and Small Employers to Job Creation in Times of High and Low Unemployment
Authors: Moscarini Giuseppe , Postel-Vinay Fabien
Published: October 2012

We document a negative correlation, at business cycle frequencies, between the net job creation rate of large employers and the level of aggregate unemployment that is much stronger than for small employers. The differential growth rate of employment between initially large and small employers has an unconditional correlation of —0.5 with the unemployment rate, and varies by about 5 percent over the business cycle. We exploit several datasets from the United States, Denmark, and France, both repeated cross sections and job flows with employer longitudinal information, spanning the last four decades and several business cycles. We discuss implications for theories of factor demand. (JEL D22, E23, E32, J23, L25)
How General Are Risk Preferences? Choices under Uncertainty in Different Domains
Authors: Einav Liran , Finkelstein Amy , Pascu Iuliana , Cullen Mark R
Published: October 2012

We analyze the extent to which individuals' choices over five employer-provided insurance coverage decisions and one 401(k) investment decision exhibit systematic patterns, as would be implied by a general utility component of risk preferences. We provide evidence consistent with an important domain-general component that operates across all insurance choices. We find a considerably weaker relationship between one's insurance decisions and 401(k) asset allocation, although this relationship appears larger for more “financially sophisticated” individuals. Estimates from a stylized coverage choice model suggest that up to 30 percent of our sample makes choices that may be consistent across all 6 domains. (JEL D12, D14, D81, G22, J33)
Trade Costs, Asset Market Frictions, and Risk Sharing
Authors: Fitzgerald Doireann
Published: October 2012

I use bilateral import data to test for and quantify the importance of trade costs and asset market frictions in explaining the failure of perfect international consumption risk sharing. I find that while frictions in international asset markets significantly impede optimal consumption risk sharing between developed and developing countries over the period 1970–2000, developed countries are close to optimal risk sharing with each other. Trade costs, in contrast, significantly impede risk sharing for all countries. (JEL E21, E44, F14, F41, G15)
Physician Agency and Adoption of Generic Pharmaceuticals
Authors: Iizuka Toshiaki
Published: October 2012

I examine physician agency in health care services in the context of the choice between brand-name and generic pharmaceuticals. I examine micro-panel data from Japan, where physicians can legally make profits by prescribing and dispensing drugs. The results indicate that physicians often fail to internalize patient costs, explaining why cheaper generics are infrequently adopted. Doctors respond to markup differentials between the two versions, indicating another agency problem. However, generics' markup advantages are short-lived, which limits their impact on increasing generic adoption. Additionally, state dependence and heterogeneous doctor preferences affected generics' adoption. Policy makers can target these factors to improve static efficiency. (JEL D82, I11, J44, L65)
Mrinal Sen: 'Rambling Thoughts' on Unforgettable Masters, Lost Friends, Enigmatic Ruins and Life
Authors: Dönmez-Colin Gönül
Published: October 2012

Mrinal Sen is the most important living filmmaker of India today. Born in 1923 in Faridpur, which is now in Bangladesh, Sen arrived in Calcutta in 1940 to study science and soon got involved in underground Leftist movements. Following India's independence (1947), a serious art cinema
emerged in Bengal, which was nurtured by the foundation of Calcutta Film Society. By 1955, Sen had given up his job as a representative for a pharmaceutical firm and made his debut as a filmmaker. This was also the year, another famous Bengali, Satyajit Ray produced his celebrated first film,
"Pather Panchali."
Cinema and Iran: Culture and Politics in the Islamic Republic
Authors: Mohammadi Ali , Egan Eric
Published: October 2012

The aim of this paper is to provide an overview of the development of cinema in Iran since the revolution and to provide a framework, (by locating it within the social, political and cultural landscape of Iran itself and by linking it to the historical development of the "third
cinema"), in which to understand, interpret and locate this evolution.
Semerah Padi: A Proposal For A New Nation
Authors: Heide William van der
Published: October 2012

The very first images of the Malaysian film, Semerah Padi, are of clouds swirling across a turning and gradually approaching earth that eventually reveals a map of the Malay Archipelago and closes in on an area in present day northern Sumatra. The music accompanying these images is
somber and the voice-over is incantatory.
Blood Spear, Mt. Fuji: Uchida Tomu's Conflicted Comeback from Manchuria
Authors: Watts Craig
Published: October 2012

Following the surrender of the Japanese in World War II, the colonial tables were turned. The Chinese took control of Manchuria and the Manchurian Film Cooperative, and the Americans took control of Japan and its film industry. In a sense, the Japanese, who had fabricated and controlled
Manchuria's film industry from 1937–1945, writing the lines to be spoken by Chinese actors in Manchurian productions, were now forced to appear as the puppet actors in an American production. In the early days of the Occupation, the overlay of democracy in Japan seemed to have been effortlessly
deployed. But in the postwar period, the ideology that drove Japan to reach new heights of modernism and atrocity on the Continent was not so effortlessly put to rest. As the Japanese cinema entered its post-war golden age, a "working out" of militarist, modernist, and feudalistic
ideology on the level of mass culture took place in Japan's packed movie theatres. In this period, celebrated filmmaker Uchida Tomu brought his Manchurian experience living on the edge of Japanese ideological extremes back to Japan with him and infused it into his conflicted 1955 samurai classic
Chiyari Fuji (Blood Spear, Mt. Fuji).
Blood Money: Woman's Desire and Consumption in Ermo
Authors: Notar Beth
Published: October 2012

As the syringe sticking out of her arm slowly fills with blood, Ermo begs the nurse to stop. The nurse ignores her until she finishes and then, handing Ermo a slip of paper, dismisses her with: "Collect your money." Not until this moment does Ermo realize that her blood donation
was actually a blood transaction. From then on she frequently returns to the hospital to sell her blood, each week growing weaker, but each week coming a step closer to her goal: having enough money to buy the biggest television set around
Formation of Korean Film Industry under Japanese Occupation
Authors: Woo Noh Kwang
Published: October 2012

The Korean term for film, cinema, or motion picture is younghwa, which comes from Japanese eiga. These two words are the same Chinese character but pronounced differently. On the other hand, the term hwaldong sajin, which corresponds to motion picture literally and sometimes means film
itself, was used at one time. To see hwaldong sajin implies to see a spectacle, an attraction, and to experience new cultures, while to see younghwa means to see or to enjoy (narrative) cinema As narrative cinema has developed, hwaldong sajin is not used any longer and the experience of hwaldong
sajin is absorbed into the experience of younghwa. In late nineteenth century, when cinema was invented and introduced to Korea, Japan colonized the country.
Different from Difference: Revisiting Kurutta ichipeiji
Authors: Abel Jonathan E.
Published: October 2012

Hailed as revolutionary for technical and narrative filmic achievements at the time of its 1926 debut, Kurutta ichipeiji (A Crazy Page) has come to represent avant-garde and even deconstructionist tendencies to recent film critics. Both critics writing at the time of its release and
those writing after its rediscovery in the mid-1970s emphasize the revolutionary character of the film; however, the terms upon which these two groups consider the film differ widely. Viewing the film within various historical enables both assessment of the degree to which the film can be
considered revolutionary and, indeed, interpretation of the film's dominant images and style. Recent critics, however, have chosen to discuss the socio-historically determined binaries of self and other and of real and fictive as constants, unrelated to differences of space and time.
Patriarchy and Male Seduction: Satyajit Ray's Devi Revisited
Authors: Sil Narasingha P.
Published: October 2012

Mirra Richard, the pretty Parisienne, was beatified, even apotheosized, in life, and when she died a respectable nonagenarian in 1973, thousands mourned the passing away of the goddess of Auroville. This good fortune of a real life human goddess eluded the fate of a rural teenager of
Victorian fiction, Dayamayi, the main character of Prabhatkumar Mukhopadhyay's obscure short story Devi (The Goddess). When it was filmed in 1960 by Satyajit Ray, Devi provoked a mixed reaction among movie-goers and critics at home––from a sense of boredom of having to watch another
film on the theme of feudal decadence, albeit less entertaining, than Jalsaghar (The Music Room, 1958), to an outrage at what some felt was the film's pronounced anti-Hindu bias.
"Heart to Heart Is Best Type of Art"— Actor-Professor Xu Zhongquan
Authors: Lent John A.
Published: October 2012

Veteran Chinese actor and drama professor Xu Zhongquan alternates living in his Beijing home and in Weston, Florida, where his son Derrick and family reside. On May 29, 2001, he was in his Beijing quarters where I interviewed him for two hours. The questions are omitted from this interview
as there were so few; like other artists excited about what they do, Xu did not need much prompting. The following are his comments. (See accompanying article he and his daughter Xu Ying wrote for background on his career.)
The Impact of Globalization on Iranian Cinema
Authors: Mohammadi Ali
Published: October 2012

In this article I am trying to develop a conceptual overview of cultural commodity relevant to the Iranian film industry and provide an analysis of cultural policy, economy and the place of Iranian film industry in the context of globalized world.
Chunhyang, chunhyang, chunhyang: Poetics of Im Kwan-Taek's Chunhyang
Authors: Choi Jinhee
Published: October 2012

Im Kwan-Taek, a leading Korean director, explores an aspect of Korean artistic heritage, pansori, in his recent film Chunhyang (2000). Korean traditions influenced by Buddhism and Shamanism have been major themes in his other films, including Mandala (1981), Aje Aje Bara Aje (1989),
and Daughter of the Flame (1983). In his film Chunhyang, Im combines two different art forms: the Korean traditional performance art pansori and cinema. Pansori was a major theme in his film, Sopyonje (1993), in which he portrays the life of the pansori performer Song-hwa, whose father sacrificed
her sight for the sake of mastering the artistry of pansori. In an interview, Im tells us that without having made Sopyonuje, Chunhyang could not have come to existence.1 Unlike Sopyonje in which pansori is incorporated within the film through the characters' performances, in Chunhyang, pansori
singing leads the narrative.
Refugees in Love and Life: An Interview with Majid Majidi
Authors: Dönmez-Colin Gönül
Published: October 2012

Majid Majidi, one of the distinguished names of new Iranian cinema started as an actor in amateur theatre groups and got roles in films after the Islamic revolution. His debut as a director and screenwriter) was with Baduk 1991), a feature film that was presented at the Directors' Fortnight
of Cannes Film Festival 1992, which also won him several national awards. His second film, Pedar The Father) (1996) received the Jury Award of San Sebastian Film Festival. He won the Grand Prix of the Americas of the Montreal World Film Festival three times in five years. The first was with
Bacheha-ye aseman (Children Of Heaven) in 1997; the second was with Rang-e-Khoda (The Color of Paradise) in 1999, and the third, in 2001, with Baran, which shared the top prize with Torzok (Abandoned) by Hungarian Arpad Sopsits. Having won several awards at its own country as well, Baran has
become one of the most successful films of the year, having gained a special meaning after the September 11 events in New York.
Mabaroshi: The Danger and Allure of Phantom Light
Authors: McDonald Keiko
Published: October 2012

In 1995, many international festivals took note of films by a new generation of directors. Two readily come to mind: Makoto Shinozaki's Okaeri and Hirokazu Koreeda's Maboroshi no hikari (Maboroshi). Both are debut feature-length films. Both offer a confident, thought-provoking approach
to a familiar subject still relevant in Japan today: the breakdown of an ordinary family. Okaeri studies a young couple's helplessness in face of the wife's decline into insanity. Maboroshi explores a young widow's growing obsession with death.
Hybridity in Contemporary Japanese Cinema: Heterogeneity in a Homogenous Society
Authors: Hyland Robert
Published: October 2012

Contemporary Japan has discovered a new vogue in a globalized aesthetic. European language is found everywhere, from non-sequitur slogans in coffee shops, to meaningless catch phrases printed on contemporary high fashion. Japan has discovered a type of occidental fetish object in the
European word - connotative of exotic Western locales, such as French Bistros or Texas barbecue restaurants. Marianna Torgovnick, in her book Gone Primitive, catalogues a history of Western fetishization of "Primitive" iconography.
The Past, the Present, and the Future An Interview with Wu Ziniu
Authors: Kong Haili
Published: October 2012

Wu Ziniu has been considered one of the most important Fifth Generation Chinese filmmakers. Wu has directed more than ten films, such as Evening Bell (1988) and Nanjing 1937 (1995), and won numerous awards both at home and abroad which includes a Silver Bear Award in the Berlin International
Film Festival. In October 2000, he was one of four featured Chinese directors at an international symposium on Chinese cinema at Swarthmore College, and lectured at Temple University, Columbia University, and New York University. Kong conducted this interview in Beijing, May 31, 2002.
The Ambivalence of P. Ramlee: Penarek Beca and Bujang Lapok in Perspective
Authors: Barnard Rohayati Paseng , Barnard Timothy P.
Published: October 2012

One of the great heroes of the Malay World is Hang Tuah, a fifteenth century Malay warrior in service to the ruler of Melaka. Hang Tuah traveled throughout Asia, and during these adventures he secured riches, concubines, and status for his patron through his multi-talented ability to
fight, sing, dance, and create poetry. Hang Tuah became an icon, the archetypical Malay whose status was solidified in the recording of an epic tale that describes his adventures, the Hikayat Hang Tuah.
Creating Truth-Telling Incentives with the Bayesian Truth Serum
Authors: Weaver Ray , Prelec Drazen
Published: October 2012

The Bayesian truth serum (BTS) is a survey scoring method that creates truth-telling incentives for respondents answering multiple-choice questions about intrinsically private matters, such as opinions, tastes, and behavior. The authors test BTS in several studies, primarily using recognition questionnaires that present items such as brand names and scientific terms. One-third of the items were nonexistent foils. The BTS mechanism, which mathematically rewards “surprisingly common” answers, both rewarded truth telling, by heavily penalizing foil recognition, and induced truth telling, in that participants who were paid according to their BTS scores claimed to recognize fewer foils than control groups, even when given competing incentives to exaggerate. Survey takers who received BTS-based payments without explanation became less likely to recognize foils as they progressed through the survey, suggesting that they learned to respond to BTS incentives despite the absence of guidance. The mechanism also outperformed the solemn oath, a competing truth-inducement mechanism. Finally, when applied to judgments about contributing to a public good, BTS eliminated the bias common in contingent valuation elicitations.
Hypoxia/Reoxygenation Impairs Memory Formation via Adenosine-Dependent Activation of Caspase 1
Authors: Chiu Gabriel S. , Chatterjee Diptaman , Darmody Patrick T. , Walsh John P. , Meling Daryl D. , Johnson Rodney W. , Freund Gregory G.
Published: October 2012

After hypoxia, a critical adverse outcome is the inability to create new memories. How anterograde amnesia develops or resolves remains elusive, but a link to brain-based IL-1 is suggested due to the vital role of IL-1 in both learning and brain injury. We examined memory formation in mice exposed to acute hypoxia. After reoxygenation, memory recall recovered faster than memory formation, impacting novel object recognition and cued fear conditioning but not spatially cued Y-maze performance. The ability of mice to form new memories after hypoxia/reoxygenation was accelerated in IL-1 receptor 1 knockout (IL-1R1 KO) mice, in mice receiving IL-1 receptor antagonist (IL-1RA), and in mice given the caspase 1 inhibitor Ac-YVAD-CMK. Mechanistically, hypoxia/reoxygenation more than doubled caspase 1 activity in the brain, which was localized to the amygdala compared to the hippocampus. This reoxygenation-dependent activation of caspase 1 was prevented by broad-spectrum adenosine receptor (AR) antagonism with caffeine and by targeted A1/A2A AR antagonism with 8-cyclopentyl-1,3-dipropylxanthine plus 3,7-dimethyl-1-propargylxanthine. Additionally, perfusion of adenosine activated caspase 1 in the brain, while caffeine blocked this action by adenosine. Finally, resolution of anterograde amnesia was improved by both caffeine and by targeted A1/A2A AR antagonism. These findings indicate that amygdala-based anterograde amnesia after hypoxia/reoxygenation is sustained by IL-1β generated through adenosine-dependent activation of caspase 1 after reoxygenation.
Population Response to Natural Images in the Primary Visual Cortex Encodes Local Stimulus Attributes and Perceptual Processing
Authors: Ayzenshtat Inbal , Gilad Ariel , Zurawel Guy , Slovin Hamutal
Published: October 2012

The primary visual cortex (V1) is extensively studied with a large repertoire of stimuli, yet little is known about its encoding of natural images. Using voltage-sensitive dye imaging in behaving monkeys, we measured neural population response evoked in V1 by natural images presented during a face/scramble discrimination task. The population response showed two distinct phases of activity: an early phase that was spread over most of the imaged area, and a late phase that was spatially confined. To study the detailed relation between the stimulus and the population response, we used a simple encoding model to compute a continuous map of the expected neural response based on local attributes of the stimulus (luminance and contrast), followed by an analytical retinotopic transformation. Then, we computed the spatial correlation between the maps of the expected and observed response. We found that the early response was highly correlated with the local luminance of the stimulus and was sufficient to effectively discriminate between stimuli at the single trial level. The late response, on the other hand, showed a much lower correlation to the local luminance, was confined to central parts of the face images, and was highly correlated with the animal's perceptual report. Our study reveals a continuous spatial encoding of low- and high-level features of natural images in V1. The low level is directly linked to the stimulus basic local attributes and the high level is correlated with the perceptual outcome of the stimulus processing.
Microtubule Plus-End Tracking Protein CLASP2 Regulates Neuronal Polarity and Synaptic Function
Authors: Beffert Uwe , Dillon Gregory M. , Sullivan Josefa M. , Stuart Christine E. , Gilbert James P. , Kambouris John A. , Ho Angela
Published: October 2012

Microtubule organization and dynamics are essential during axon and dendrite formation and maintenance in neurons. However, little is known about the regulation of microtubule dynamics during synaptic development and function in mammalian neurons. Here, we present evidence that the microtubule plus-end tracking protein CLASP2 (cytoplasmic linker associated protein 2) is a key regulator of axon and dendrite outgrowth that leads to functional alterations in synaptic activity and formation. We found that CLASP2 protein levels steadily increase throughout neuronal development in the mouse brain and are specifically enriched at the growth cones of extending neurites. The short-hairpin RNA-mediated knockdown of CLASP2 in primary mouse neurons decreased axon and dendritic length, whereas overexpression of human CLASP2 caused the formation of multiple axons, enhanced dendritic branching, and Golgi condensation, implicating CLASP2 in neuronal morphogenesis. In addition, the CLASP2-induced morphological changes led to significant functional alterations in synaptic transmission. CLASP2 overexpression produced a large increase in spontaneous miniature event frequency that was specific to excitatory neurotransmitter release. The changes in presynaptic activity produced by CLASP2 overexpression were accompanied by increases in presynaptic terminal circumference, total synapse number, and a selective increase in presynaptic proteins that are involved in neurotransmitter release. Also, we found a smaller increase in miniature event amplitude that was accompanied by an increase in postsynaptic surface expression of GluA1 receptor localization. Together, these results provide evidence for involvement of the microtubule plus-end tracking protein CLASP2 in cytoskeleton-related mechanisms underlying neuronal polarity and interplay between microtubule stabilization and synapse formation and activity.
Change in Choice-Related Response Modulation in Area MT during Learning of a Depth-Discrimination Task is Consistent with Task Learning
Authors: Uka Takanori , Sasaki Ryo , Kumano Hironori
Published: October 2012

What are the neural mechanisms underlying improvement in perceptual performance due to learning? A recent study using motion-direction discrimination suggested that perceptual learning is due to improvements in the “readout” of sensory signals in sensory–motor cortex and not to improvements in neural sensitivity of the sensory cortex. To test the generality of this hypothesis, we examined this in a similar but different task. We recorded from isolated neurons in the middle temporal (MT) area while monkeys were trained in a depth-discrimination task. Consistent with earlier reports using direction discrimination, we found no long-term improvement in MT neuron sensitivity to depth, although monkey performance improved over months with extensive training, even when taking out the effect of behavioral biases. We further addressed improvement in the readout of sensory signals by focusing on choice-related response modulation [choice probability (CP)]. CP increased with training, suggesting an improvement in the readout of sensory signals from MT. CP, however, correlated more strongly with lapse rate than psychophysical threshold, suggesting that changes in readout may be restricted to early phases of learning. To test how behavioral learning, as well as the magnitude of CP, transferred across visual fields, we measured CP variation in one hemifield after training monkeys on the depth-discrimination task in the opposite hemifield. CP was large from the beginning of training in the untrained hemifield, even though a small but significant improvement in sensitivity was observed behaviorally. Overall, our findings are consistent with the idea that increases in CP reflect task learning.
Stochastic Generation of Gamma-Band Activity in Primary Visual Cortex of Awake and Anesthetized Monkeys
Authors: Xing Dajun , Shen Yutai , Burns Samuel , Yeh Chun-I , Shapley Robert , Li Wu
Published: October 2012

Oscillatory neural activity within the gamma band (25–90 Hz) is generally thought to be able to provide a timing signal for harmonizing neural computations across different brain regions. Using time–frequency analyses of the dynamics of gamma-band activity in the local field potentials recorded from monkey primary visual cortex, we found identical temporal characteristics of gamma activity in both awake and anesthetized brain states, including large variability of peak frequency, brief oscillatory epochs (<100 ms on average), and stochastic statistics of the incidence and duration of oscillatory events. These findings indicate that gamma-band activity is temporally unstructured and is inherently a stochastic signal generated by neural networks. This idea was corroborated further by our neural-network simulations. Our results suggest that gamma-band activity is too random to serve as a clock signal for synchronizing neuronal responses in awake as in anesthetized monkeys. Instead, gamma-band activity is more likely to be filtered neuronal network noise. Its mean frequency changes with global state and is reduced under anesthesia.
Zfp423/OAZMutation Reveals the Importance of Olf/EBF Transcription Activity in Olfactory Neuronal Maturation
Authors: Roby Yang A. , Bushey Michael A. , Cheng Li E. , Kulaga Heather M. , Lee Se-Jin , Reed Randall R.
Published: October 2012

Zfp423/OAZ, a multi-zinc finger protein, is proposed to participate in neuronal differentiation through interactions with the Olf/EBF (O/E) family of transcription factors and mediate extrinsic BMP signaling pathways. These activities are associated with distinct domains of the Olf/EBF-associated zinc finger (OAZ) protein. Sustained OAZ expression arrests olfactory sensory neurons (OSNs) at an immature state and alters olfactory receptor expression, but the mechanism remains elusive. We show here that constitutive expression of a C-terminal mutant OAZ (OAZΔC) in mice that selectively disrupts OAZ–O/E interaction while retaining other activities, exhibits apparently normal OSN differentiation. Additionally, interfering with potential BMP signaling pathways by inducible Follistatin expression in adult mice does not alter the neuronal lineage or differentiation status. Our results indicate that O/E-mediated processes are essential for the differentiation of OSNs and the establishment of a mature phenotype. BMP signaling pathways, if they are active in normal adult olfactory epithelium, may play a minor role in this tissue.
Conductivity of Graphene-Like Thin Films Prepared from Chemically Exfoliated Carbon Nanotubes (CNTs), Highly Oriented Pyrolytic Graphite (HOPG), Natural Flake Graphite, and Carbon Powder
Authors: Marchese Matthew M. , Gerhardt Rosario A.
Published: October 2012

The use of super acids such as chlorosulfonic acid (CSA) has proven to be extremely effective at exfoliating different forms of graphite in high concentrations without covalently functionalizing the surface of the graphene. Once quenched, the acid solutions can then be vacuum filtered through acid resistant polypropylene filter paper with an average pore size of 0.2 μm to collect the exfoliated carbon into a free standing retentate film. These films can then be easily washed, removed, and redispersed into solution by sonicating the films in a surfactant solution. Films were deposited onto various substrates using a range of spin coating parameters. This study has found that exfoliated CNTs provide the best conductivity out of the four types of chemically exfoliated carbon structures studied. CNTs have also proven to be the easiest type of exfoliated carbon to disperse and are able to stay in solution with less than 1%wt surfactant. The findings have shown that the electrical conductivity of the spin coated films actually increases with RPM and is inversely proportional to the film thickness. It is possible to achieve electrical conductivities as high as 10,507 ± 3728.64 [S/m] while still maintaining the transparency of the thin films. The initial spin coating step is more efficient at low ramp rates around 100 rpm/s and results in very smooth films. High spin speeds of 1800 rpm during the casting stage are found to play a large role in improving the conductivity of the films. Lastly, drying the samples on a hot plate for 5 min. on high has significantly improved the films electrical properties and virtually eliminated the need for tedious and expensive plasma cleaning treatments.
Rare-earth Activated Glass and Glass-Ceramic for Neutron Detection
Authors: Dai Wei , Marcacci Henry , Lynch Brendan , Menkara Hisham , Wagner Brent , Kang Zhitao , Wang Cai-Lin , Diawara Yacouba , Engels Ralf
Published: October 2012

Neutron detection scintillators based on rare-earth activated transparent glass and glass-ceramics are reported. Ce3+ doped gadolinium halides in 6LiF modified aluminosilicate glass matrices were synthesized by a melt-quench method followed by annealing. Their optical properties and alpha, neutron scintillation performance were investigated and compared to conventional 6Li-based scintillating glass.
Antitumor, antibiotic and antileishmanial properties of the Pyranonaphthoquinone Psychorubrin from Mitracarpus frigidus
Authors: Fabri Rodrigo L. , Grazul Richard M. , Carvalho Lidiane O. de , Coimbra Elaine S. , Cardoso Gabriele M.M. , Souza-Fagundes Elaine M. de , Silva Adilson D. da , Scio Elita
Published: October 2012

The bioactivity guided fractionation of the dichloromethane extract of Mitracarpus frigidus afforded the pyranonaphthoquinone psychorubrin. This compound, hitherto unknown in the genus Mitracarpus, had its biological activity evaluated against one panel of bacteria and two fungi, three tumor cell lines (HL60, Jurkat and MCF-7) and four Leishmania species. Its identity was confirmed unambiguously by ¹H, 13C, ¹H-COSY, IR and UV-Vis spectroscopy and mass spectrometry. Psychorubrin displayed a very promising antitumor with IC50 of 4.5, 5.6 and 1.1 µM for HL60, Jurkat and MCF-7 cell lines, respectively. Antimicrobial activity, mainly against Cryptococcus neoformans (MIC of 87.3 µM) was observed. A pronounced antileishmanial potential was also verified with IC50 varying from 1.7 to 2.7 µM for the Leishmania species tested. This is the first report of the presence of pyranonapthoquinones in the Mitracarpus genus, which may serve as a chemotaxonomical marker.
Produtividade de pessegueiros 'Aurora-1' em diferentes espaçamentos e métodos de propagação do porta-enxerto 'Okinawa'
Authors: Mayer Newton Alex , Pereira Fernando Mendes
Published: October 2012

O presente trabalho teve por objetivo estudar a influência de diferentes espaçamentos entre plantas (6x2 m, 6x3 m e 6x4 m) e de métodos de propagação do porta-enxerto 'Okinawa' (sementes e estacas herbáceas) em variáveis relativas à produção da cultivar Aurora-1 de pessegueiro. O experimento foi desenvolvido em condições de campo, no município de Vista Alegre do Alto (SP), adotando-se as tecnologias recomendadas para a cultura do pessegueiro na região, e as avaliações foram realizadas no segundo e no terceiro ano após o plantio das mudas. Nas condições experimentais adotadas, pode-se concluir que o método de propagação do porta-enxerto 'Okinawa' não interfere em nenhuma das características vegetativas e produtivas da cv. Aurora-1, nas duas safras avaliadas. O espaçamento de 6x2 m promove significativos aumentos na produtividade do pessegueiro 'Aurora-1'.
Adubação com fósforo em cana-soca e sua interação com magnésio
Authors: Zambrosi Fernando César Bachiega
Published: October 2012

Existem dúvidas a respeito da eficiência da adubação fosfatada na cana-soca, bem como, em relação às interações do fósforo (P) com outros nutrientes que poderiam afetar as respostas da cultura à reaplicação de P. Realizou-se um estudo para avaliar os possíveis efeitos da aplicação de P (45 e 90 kg ha-1 de P2O5) na ausência ou na presença de adubação com Mg (50 kg ha-1 de Mg) sobre a produção de colmos da cana-soca. A adubação fosfatada promoveu acréscimos de 17% na produção de colmos em relação ao tratamento controle (sem fertilizante fosfatado), porém, não dependeu da adubação com Mg, indicando que a aplicação deste nutriente não foi determinante para a ocorrência de resposta ao P. O estado nutricional em P da cana-de-açúcar também não foi influenciado pela aplicação de Mg, sendo alterado exclusivamente pela adubação fosfatada. O teor foliar de P aumentou significativamente (p<0,05) de 1,4 g kg-1 no controle para 1,7 g kg-1 e 1,9 g kg-1 nos tratamentos que receberam 45 e 90 kg ha-1 de P2O5 respectivamente. A eficiência de uso de fertilizante nitrogenado e potássico para a produção de colmos foi aumentada com a adubação fosfatada, com ganhos de 21% e 16% respectivamente. Os resultados sugerem que o incremento de produtividade na soqueira da cana-de-açúcar em solo com baixo teor disponível de P pode ser obtido com a reaplicação do nutriente, o que deve estar relacionado à melhoria do estado nutricional em P da cultura.
Efeitos do controle nas intenções comportamentais dos consumidores insatisfeitos
Authors: Pacheco Natália Araujo , Santos Cristiane Pizzutti dos , Lunardo Renaud
Published: October 2012

O controle tem sido citado como elemento essencial para o desenvolvimento de interações interpessoais satisfatórias, estando positivamente relacionado à satisfação e a respostas afetivas e comportamentais positivas na área do comportamento do consumidor. Este trabalho investiga o impacto dos controles comportamental, cognitivo e de decisão, representados respectivamente pelas variáveis coprodução, informação e opção de reembolso, nas intenções de recompra e de boca-a-boca positivo após compras insatisfatórias. Os resultados de dois estudos experimentais conduzidos indicam que coprodução e opção de reembolso são capazes de elevar os níveis de intenção de recompra e de boca-a-boca positivo após episódios de insatisfação, enquanto a informação não tem efeito nas intenções comportamentais, mas modera o efeito da coprodução nas intenções comportamentais.
Personal and Social Performance (PSP) scale for patients with schizophrenia: translation to Portuguese, cross-cultural adaptation and interrater reliability
Authors: Menezes Anny Karinna Pires Mendes , Macedo Gamaliel , Mattos Paulo , Sá Júnior Antonio Reis de , Louzã Mario Rodrigues
Published: October 2012

INTRODUCTION: Schizophrenia is a chronic mental disorder associated with impairment in social functioning. The most widely used scale to measure social functioning is the GAF (Global Assessment of Functioning), but it has the disadvantage of measuring at the same time symptoms and functioning, as described in its anchors. OBJECTIVES:Translation and cultural adaptation of the PSP, proposing a final version in Portuguese for use in Brazil. METHODS: We performed five steps: 1) translation; 2) back translation; 3) formal assessment of semantic equivalence; 4) debriefing; 5) analysis by experts. Interrater reliability (Intraclass correlation, ICC) between two raters was also measured. RESULTS: The final version was applied by two independent investigators in 18 adults with schizophrenia (DSM-IV-TR). The interrater reliability (ICC) was 0.812 (p < 0.001). CONCLUSION: The translation and adaptation of the PSP had an adequate level of semantic equivalence between the Portuguese version and the original English version. There were no difficulties related to understanding the content expressed in the translated texts and terms. Its application was easy and it showed a good interrater reliability. The PSP is a valid instrument for the measurement of personal and social functioning in schizophrenia.
Fungicides, seed dresser adjuvants and storage time in the control of Drechslera teres in barley seeds
Authors: Reis Erlei Melo , Danelli Anderson , Casa Ricardo Trezzi
Published: October 2012

In experiments conducted in laboratory, the effect of fungicides, seed dresser adjuvants and storage time in the control of Drechslera teres in seeds of barley cultivar BRS Elis, with 58% incidence, was quantified. Fungicides indicated by barley research (carboxin + thiram, difenoconazole and triadimenol) compared with the mixture carbendazim + iprodione were tested. As seed dresser adjuvants, water (500m mL/100 Kg) and a polymer (150 mL/100 Kg) were used. Treated seeds were stored in paper bags and kept in the refrigerator at 5ºC. At 30-day intervals during six months, seeds were plated on semi-selective Reis's medium (1983). The best control was obtained by the mixtures carboxin + thiram and carbendazim + iprodione and the polymer as seed dresser. The control efficiency was improved by the storage time without negatively affecting seed germination. Due to the transmission efficiency, the fungus eradication in seeds should be pursued.
Epidemiologia da mela e produtividade do feijoeiro-comum tratado com fungicidas
Authors: Costa-Coelho Gesimária Ribeiro , Lobo Júnior Murillo , Café-Filho Adalberto Corrêa
Published: October 2012

O efeito dos fungicidas azoxistrobina, carbendazim, mancozebe, tebuconazole, hidróxido de fenilestanho, piraclostrobina, trifloxistrobina + ciproconazol, trifloxistrobina + propiconazol e clorotalonil no progresso da mela e na produtividade do feijoeiro foi avaliado em campo e casa de vegetação. No campo, três experimentos foram conduzidos nas estações chuvosas de 2004/05, 2005/06 e 2006/07, em blocos ao acaso com quatro repetições.Na safra 2004/05 foi realizada apenas uma aplicação, aos 45 dias após o plantio (DAP); em 2005/06 foram realizadas duas aplicações aos 30 e 45 DAP e em 2006/07 foram realizadas três aplicações, aos 30, 45 e 60 DAP. A avaliação da severidade da doença foi feita semanalmente, atribuindo-se notas de 1 (sem sintomas) a 9 (acima de 90% da área foliar destruída) e taxas de progresso da doença foram calculadas após o ajuste das curvas de progresso ao modelo logístico. Os resultados mostraram que uma única aplicação de qualquer dos produtos, aos 45 DAP, foi ineficiente para o controle da taxa de progresso da mela (taxa média, r = 0,2348). A eficiência do controle aumentou com o incremento do número de aplicações e aplicações mais precoces, iniciando-se aos 30 DAP (médias de r = 0,1988 e 0,1671 em 2005/06 e 2006/07, respectivamente). Com três aplicações,as menores severidades de doença foram observadas com hydróxido de fenil estanho, trifloxistrobina + propiconazol e trifloxistrobina + cyproconazol. Em casa de vegetação, o efeito protetor e curativo dos fungicidas foi estudado com aplicação dos produtos em pré ou pós-inoculação de folíolos, através da avaliação do diâmetro das lesões. Todos os fungicidas apresentaram tanto efeito protetor quanto curativo, mas os melhores resultados foram observados em aplicação preventiva.Foi encontrada alta correlação negativa entre intensidade da mela e a produção do feijoeiro e o ganho em produtividade com uso de fungicidas chegou a 304 %.
Diferentes concentrações do inóculo de Cercospora sojina na intensidade da mancha foliar "olho-de-rã" em soja
Authors: Camera Juliane Nicolodi , Deuner Carolina Cardoso , Reis Erlei Melo
Published: October 2012

A mancha foliar "olho-de-rã", cujo agente causal é o fungo Cercospora sojina, causa grandes perdas no cultivo da soja, principalmente na Argentina. Em experimento conduzido em laboratório e câmara climatizada, objetivou-se verificar o efeito de diferentes concentrações do inóculo de C. sojina na intensidade da mancha foliar "olho-de-rã" em folíolos de soja. As concentrações de conídios utilizadas foram de 10x10³, 20x10³, 30x10³, 40x10³, 50x10³ e 60x10³ conídios.mL-1, com e sem espalhante. Após a inoculação dos conídios por aspersão sobre os folíolos de soja, as plantas foram mantidas com molhamento foliar de 48 horas. Decorrido este período, as plantas permaneceram em câmara climatizada, em temperatura de 25 ºC por 15 dias. Avaliou-se a severidade, número e diâmetro de lesões. A concentração de 35.000 conídios.mL-1 com espalhante gerou intensidade de doença que possibilita a quantificação rápida e precisa da doença, podendo ser utilizada em futuros trabalhos de pesquisa.