bluuebunny/crossref_metadata_2025_split huggingface dataset:
Space Station Solar Array Joint Repair
Authors: Loewenthal Stuart , Allmon Curtis , Reznik Carter , Mcfatter Justin , Davis Robert E. 
Published: December 2015

Abstract
In October 2007, the International Space Station (ISS) crew noticed a vibrating camera in the vicinity of Starboard Solar Alpha Rotary Joint (SARJ). It had less than 5 months of run time when the anomaly was observed. This 3.2 m-diameter bearing joint supports solar arrays that power the station critical to its operation. The crew performed an EVA to identify what was causing the vibration. It was discovered that one of the 3 bearing tracks of this unconventional bearing had significant spalling damage. This paper discussed the SARJ’s unique bearing design and the vulnerability in its design leading to the observed anomaly. The design of an SARJ vacuum test rig was also described along with the results of a life test that validated the proposed repair should extend the life of the SARJ a minimum of 18 years on-orbit.
Impact of Synthetic Hydrocarbon in Biofuels on Two Polysulfide Aircraft Fuel-Tank Sealants
Authors: Yang Zhiyuan , Liu Hua , Ye Liwei , Chen Kai 
Published: December 2015

Abstract
The impacts of synthetic hydrocarbon in biofuels on two fuel-tank polysulfide sealants were systematically studied in this research. Synthetic hydrocarbon was derived from waste oils and fats and produced by hydroprocessed esters and fatty acids process (HEFA). The experimental results revealed that the volume of two polysulfide sealants shrunk after being immersed in the pure biofuels for 28 days at 93°C. Furthermore, mechanical properties, such as elongation rate and hardness, failed to satisfy the requirement of the specification. The experimental results also showed that the volume swell of two polysulfide sealants varied from jet reference fuel (JRF) more than 5 % after being immersed in the blended fuels when neat biofuel component was mixed with No. 3 jet fuel in a volume ratio of 50/50. The mechanical properties of elongation and hardness still cannot meet the requirements of the specification. The results demonstrated that synthetic hydrocarbons in biofuels would have a significant impact on the polysulfide sealants of the aircraft fuel tank.
Advances in Gypsum Technologies and Building Systems
Authors: Wessel Robert A. , Shipp Paul H. , Rosenthal Guy L. 
Published: December 2015

Description
This compilation of Selected Technical Papers, STP1588, Advances in Gypsum Technologies and Building Systems, contains 11 peer-reviewed papers presented at a symposium held May 21, 2015 in Anaheim, CA. The symposium was sponsored by ASTM International Committee C11 on Gypsum and Related Building Materials and Systems and Subcommittee C11.01 on Specifications and Test Methods for Gypsum Products. The Symposium Chairpersons and STP Editors are Dr. Robert A. Wessel, Gypsum Association, Hyattsville, MD, USA and Dr. Paul H. Shipp and Dr. Guy L. Rosenthal, USG Corporation, Libertyville, IL, USA.
Excitatory Postrhinal Projections to Principal Cells in the Medial Entorhinal Cortex
Authors: Koganezawa Noriko , Gisetstad Ragnhild , Husby Ellen , Doan Thanh P. , Witter Menno P. 
Published: December 2015

The postrhinal cortex (POR) provides substantial input to the entorhinal cortex, mainly targeting superficial layers of the medial entorhinal cortex (MEC). Major inputs to POR originate in the visual and parietal cortex, thus providing neurons in MEC with a subset of cortical information relevant to their spatial firing properties. The POR takes a position that is comparable with that of the perirhinal cortex (PER) with regard to the lateral entorhinal cortex (LEC). Neurons in LEC and MEC show different functional properties likely reflecting differences in their respective inputs. Projections from PER to LEC exert a main inhibitory influence, which may relate to the sparse object-selective firing in LEC. In view of the continuous, spatially modulated firing properties of principal neurons in MEC, we tested in rats the hypothesis that projections from POR to MEC are functionally different from the PER-to-LEC counterpart in providing an excitatory drive to MEC. Our combined confocal and quantitative electron-microscopic observations indicated that POR projections target mainly principal cells in MEC, including neurons that project to the hippocampus. The ultrastructure of the majority of the synapses indicated that they are excitatory. Voltage-sensitive dye imaging in sagittal slices confirmed this morphologically derived conclusion, showing that the MEC network always responded with an overall depolarization, indicative for net excitatory transmission.In vitrosingle-cell recordings from principal cells showed only excitatory responses upon POR stimulation. These results show that POR provides an excitatory projection to MEC, differing fundamentally from the inhibitory projection of PER to LEC.SIGNIFICANCE STATEMENTThe study provides anatomical and electrophysiological data indicating that projections from the postrhinal cortex to the medial entorhinal cortex (MEC) are excitatory, providing the substrate for high probability of information transfer and thus a continuous input stream into MEC. This is a relevant component of the spatial navigational network found in MEC. The findings are in contrast to previous reports on the parallel pathway from the perirhinal cortex to the lateral entorhinal cortex. This pathway, characterized by a preponderance of inhibitory connections, mediates information transfer with a low probability, likely related to the discontinuous object-related firing of neurons in the lateral entorhinal cortex.
Brief Dark Exposure Reduces Tonic Inhibition in Visual Cortex
Authors: Huang Shiyong , Hokenson Kristen , Bandyopadhyay Sabita , Russek Shelley J. , Kirkwood Alfredo 
Published: December 2015

Tonic inhibition mediated by extrasynaptic GABAAreceptors (GABARs) sensing ambient levels of GABA can profoundly alter the membrane input resistance to affect cellular excitability. Therefore, regulation of tonic inhibition is an attractive mechanism to control the levels of cortical firing. In cortical pyramidal cells, tonic inhibition is regulated by age and several neurotransmitters and is affected by stroke and epilepsy. However, the possible role of sensory experience has not been examined. Here, we report that a brief 2-day exposure to dark reduces by 1/3 the inhibitory tonic conductance recorded in layer II/III pyramidal cells of the mouse juvenile (postnatal day 12–27) visual cortex. In these cells, tonic inhibition is carried primarily by GABARs containing the δ subunit. Consistently, the dark exposure reduction in conductance was associated with a reduction in δ subunit levels, which were not affected in control frontal cortex. We propose that a deprivation-induced reduction in tonic inhibition might serve a homeostatic function by increasing the firing levels of cells in deprived cortical circuits.SIGNIFICANCE STATEMENTPreviousin vivostudies reported rapid increases in spontaneous activity after visual deprivation. These adaptive responses to deprivation are believed to reflect a reduction in the recruitment of inhibitory circuits. Notably, the possible role of tonic GABAergic inhibition, which strongly limits cellular and network excitability, has not been examined. We report that a brief 2-day exposure to dark reduces both the conductance of tonic inhibition in layer 2/3 pyramidal cells and the expression of receptors containing the δ-GABAAreceptor subunit, the principal carrier of tonic inhibition in these cells. These results suggest that the early phases of homeostatic adaptations to sensory deprivation might result from modulation of GABAergic function at multiple levels.
Synaptic Targets of Medial Septal Projections in the Hippocampus and Extrahippocampal Cortices of the Mouse
Authors: Unal Gunes , Joshi Abhilasha , Viney Tim J. , Kis Viktor , Somogyi Peter 
Published: December 2015

Temporal coordination of neuronal assemblies among cortical areas is essential for behavioral performance. GABAergic projections from the medial septum and diagonal band complex exclusively innervate GABAergic interneurons in the rat hippocampus, contributing to the coordination of neuronal activity, including the generation of theta oscillations. Much less is known about the synaptic target neurons outside the hippocampus. To reveal the contribution of synaptic circuits involving the medial septum of mice, we have identified postsynaptic cortical neurons in wild-type and parvalbumin-Cre knock-in mice. Anterograde axonal tracing from the septum revealed extensive innervation of the hippocampus as well as the subiculum, presubiculum, parasubiculum, the medial and lateral entorhinal cortices, and the retrosplenial cortex. In all examined cortical regions, many septal GABAergic boutons were in close apposition to somata or dendrites immunopositive for interneuron cell-type molecular markers, such as parvalbumin, calbindin, calretinin, N-terminal EF-hand calcium-binding protein 1, cholecystokinin, reelin, or a combination of these molecules. Electron microscopic observations revealed septal boutons forming axosomatic or axodendritic type II synapses. In the CA1 region of hippocampus, septal GABAergic projections exclusively targeted interneurons. In the retrosplenial cortex, 93% of identified postsynaptic targets belonged to interneurons and the rest to pyramidal cells. These results suggest that the GABAergic innervation from the medial septum and diagonal band complex contributes to temporal coordination of neuronal activity via several types of cortical GABAergic interneurons in both hippocampal and extrahippocampal cortices. Oscillatory septal neuronal firing at delta, theta, and gamma frequencies may phase interneuron activity.SIGNIFICANCE STATEMENTDiverse types of GABAergic interneurons coordinate the firing of cortical principal cells required for memory processes. During wakefulness and rapid eye movement sleep, the rhythmic firing of cortical GABAergic neurons plays a key role in governing network activity. We investigated subcortical GABAergic projections in the mouse that extend from the medial septum/diagonal band nuclei to GABAergic neurons in the hippocampus and related extrahippocampal cortical areas, including the medial entorhinal cortex. These areas contribute to navigation and show theta rhythmic activity. We found selective GABAergic targeting of different groups of cortical GABAergic neurons, immunoreactive for combinations of cell-type markers. As septal GABAergic neurons also fire rhythmically, their selective innervation of cortical GABAergic neurons suggests an oscillatory synchronization of neuronal activity across functionally related areas.
Visualization of Ca2+Filling Mechanisms upon Synaptic Inputs in the Endoplasmic Reticulum of Cerebellar Purkinje Cells
Authors: Okubo Yohei , Suzuki Junji , Kanemaru Kazunori , Nakamura Naotoshi , Shibata Tatsuo , Iino Masamitsu 
Published: December 2015

The endoplasmic reticulum (ER) plays crucial roles in intracellular Ca2+signaling, serving as both a source and sink of Ca2+, and regulating a variety of physiological and pathophysiological events in neurons in the brain. However, spatiotemporal Ca2+dynamics within the ER in central neurons remain to be characterized. In this study, we visualized synaptic activity-dependent ER Ca2+dynamics in mouse cerebellar Purkinje cells (PCs) using an ER-targeted genetically encoded Ca2+indicator, G-CEPIA1er. We used brief parallel fiber stimulation to induce a local decrease in the ER luminal Ca2+concentration ([Ca2+]ER) in dendrites and spines. In this experimental system, the recovery of [Ca2+]ERtakes several seconds, and recovery half-time depends on the extent of ER Ca2+depletion. By combining imaging analysis and numerical simulation, we show that the intraluminal diffusion of Ca2+, rather than Ca2+reuptake, is the dominant mechanism for the replenishment of the local [Ca2+]ERdepletion immediately following the stimulation. In spines, the ER filled almost simultaneously with parent dendrites, suggesting that the ER within the spine neck does not represent a significant barrier to Ca2+diffusion. Furthermore, we found that repetitive climbing fiber stimulation, which induces cytosolic Ca2+spikes in PCs, cumulatively increased [Ca2+]ER. These results indicate that the neuronal ER functions both as an intracellular tunnel to redistribute stored Ca2+within the neurons, and as a leaky integrator of Ca2+spike-inducing synaptic inputs.SIGNIFICANCE STATEMENTCa2+is a key messenger that regulates neuronal functions in the brain. Although the endoplasmic reticulum (ER) plays indispensable roles as a source and sink of Ca2+, technical difficulties have impeded the analysis of Ca2+dynamics within the ER. In this study, we have used a genetically encoded ER Ca2+indicator to visualize Ca2+dynamics within the neuronal ER. We found that Ca2+-mobilizing synaptic inputs locally decreased the ER Ca2+concentration, followed by Ca2+replenishment by intraluminal Ca2+diffusion throughout the ER of dendrites and spines. Furthermore, Ca2+spike-inducing synaptic inputs cumulatively increased the Ca2+content of the ER. Thus, our study indicates that the ER functions both as a tunnel to redistribute stored Ca2+and as a leaky integrator of synaptic inputs.
Very Early Brain Damage Leads to Remodeling of the Working Memory System in Adulthood: A Combined fMRI/Tractography Study
Authors: Froudist-Walsh Seán , Karolis Vyacheslav , Caldinelli Chiara , Brittain Philip J. , Kroll Jasmin , Rodríguez-Toscano Elisa , Tesse Marcello , Colquhoun Matthew , Howes Oliver , Dell'Acqua Flavio , Thiebaut de Schotten Michel , Murray Robin M. , Williams Steven C.R. , Nosarti Chiara 
Published: December 2015

The human brain can adapt to overcome injury even years after an initial insult. One hypothesis states that early brain injury survivors, by taking advantage of critical periods of high plasticity during childhood, should recover more successfully than those who suffer injury later in life. This hypothesis has been challenged by recent studies showing worse cognitive outcome in individuals with early brain injury, compared with individuals with later brain injury, with working memory particularly affected. We invited individuals who suffered perinatal brain injury (PBI) for an fMRI/diffusion MRI tractography study of working memory and hypothesized that, 30 years after the initial injury, working memory deficits in the PBI group would remain, despite compensatory activation in areas outside the typical working memory network. Furthermore we hypothesized that the amount of functional reorganization would be related to the level of injury to the dorsal cingulum tract, which connects medial frontal and parietal working memory structures. We found that adults who suffered PBI did not significantly differ from controls in working memory performance. They exhibited less activation in classic frontoparietal working memory areas and a relative overactivation of bilateral perisylvian cortex compared with controls. Structurally, the dorsal cingulum volume and hindrance-modulated orientational anisotropy was significantly reduced in the PBI group. Furthermore there was uniquely in the PBI group a significant negative correlation between the volume of this tract and activation in the bilateral perisylvian cortex and a positive correlation between this activation and task performance. This provides the first evidence of compensatory plasticity of the working memory network following PBI.SIGNIFICANCE STATEMENTHere we used the example of perinatal brain injury (PBI) associated with very preterm birth to study the brain's ability to adapt to injury sustained early in life. In adulthood, individuals with PBI did not show significant deficits in working memory, but exhibited less activation in typical frontoparietal working memory areas. They also showed a relative overactivation of nontask-specific brain areas (perisylvian cortex) compared with controls, and such activation was negatively correlated with the size of white matter pathways involved in working memory (dorsal cingulum). Furthermore, this “extra” activation was associated with better working memory performance and could represent a novel compensatory mechanism following PBI. Such information could inform the development of neuroscience-based cognitive interventions following PBI.
The Double-Strand Break Landscape of Meiotic Chromosomes Is Shaped by the Paf1 Transcription Elongation Complex in Saccharomyces cerevisiae
Authors: Gothwal Santosh K , Patel Neem J , Colletti Meaghan M , Sasanuma Hiroyuki , Shinohara Miki , Hochwagen Andreas , Shinohara Akira 
Published: December 2015

Abstract
Histone modification is a critical determinant of the frequency and location of meiotic double-strand breaks (DSBs), and thus recombination. Set1-dependent histone H3K4 methylation and Dot1-dependent H3K79 methylation play important roles in this process in budding yeast. Given that the RNA polymerase II associated factor 1 complex, Paf1C, promotes both types of methylation, we addressed the role of the Paf1C component, Rtf1, in the regulation of meiotic DSB formation. Similar to a set1 mutation, disruption of RTF1 decreased the occurrence of DSBs in the genome. However, the rtf1 set1 double mutant exhibited a larger reduction in the levels of DSBs than either of the single mutants, indicating independent contributions of Rtf1 and Set1 to DSB formation. Importantly, the distribution of DSBs along chromosomes in the rtf1 mutant changed in a manner that was different from the distributions observed in both set1 and set1 dot1 mutants, including enhanced DSB formation at some DSB-cold regions that are occupied by nucleosomes in wild-type cells. These observations suggest that Rtf1, and by extension the Paf1C, modulate the genomic DSB landscape independently of H3K4 methylation.
Black Militants and Asian American Model Minorities: Contesting Oppositional Representations; or, On Afro-Asian Solidarities
Authors: Fujino Diane C. 
Published: December 2015

There is a longstanding assumption that Asian Americans gain mobility through nonpolitical means. This is usually explained through reference to cultural values or historical experiences. From a cultural perspective, Asian values are posited to coincide with American middle-class values, such as respect for authority, diligence, self-discipline, and high motivation for achievement, thus facilitating Asian American success. I contend that the invisibility of Asian American political activism is not primarily the result of cultural values, but rather of differential racialization, or ways that particular kinds of racial meanings are imputed to different groups. That in the first half of the twentieth century Japanese Americans were viewed as hyperpolitical and hyperaggressive yellow-peril threats points to the ways that racialized images change over time. They have been influenced by transformations in the political economy and international political alliances, rather than remaining a static feature of culture. Moreover, the fact that the images of Japanese Americans and African Americans were historically inverted suggests the social constructedness of the representations themselves. This difference speaks not only to the way racism operates but also to the very construction of US society. By the late 1960s, Asian American activists were creating self-images: promoting community empowerment rather than individual mobility, they drew heavily from Black Power politics and consciously forged Afro-Asian solidarities. I examine the writings of a leading Asian American Movement (AAM) organization, the Asian American Political Alliance, to explore the ways the AAM worked to create this new racial paradigm. I conclude with a focus on the recycling of assimilationist theories to discuss race and politics in today’s age of multiculturalism and so-called “postracial” politics.
Exosome-Carried microRNA-375 Inhibits Cell Progression and Dissemination via Bcl-2 Blocking in Colon Cancer
Authors: Zaharie Florin , Muresan Mihai-Stefan , Petrushev Bobe , Berce Cristian , Gafencu Grigore-Aristide , Selicean Sonia , Jurj Ancuta , Cojocneanu-Petric Roxana , Lisencu Cosmin-Ioan , Pop Laura-Ancuta , Pileczki Valentina , Eniu Dan , Muresan Mihai-Andrei , Zaharie Roxana , Berindan-Neagoe Ioana , Tomuleasa Ciprian , Irimie Alexandru 
Published: December 2015

Background: Worldwide, colorectal cancer (CRC) is the third most common cancer in men and second in women. The aim of the current study was to identify whether the miR-375 is indeed down-regulated in metastatic CRC and if it could be considered as a potential minimally invasive prognostic biomarker for CRC.
Methods. Exosomes were isolated and characterized from patients with liver metastasis from CCR. The characterization of exosome was performed using TEM/SEM. HCT116 cells were treated with miR-375 mimic, NSM and miR-375 inhibitor. Functional assays included cell counting assay for 14 days, Matrigel invasion assay, apoptosis assay by flow cytometry using Annexin V-FITC, RT-PCR and Western blotting.
Results. Increased proliferation potential was proven for the cells transfected with miR-375 inhibitor, while the miR-375 mimic decreased the cell number. The cells transfected with the miR-375 inhibitor are aggressive and cross the membrane; 3.84% of the cells transfected with the miR-375 inhibitor entered apoptosis, while 6.45% of those transfected with the non-specific mimic were in programmed cell death, less than those transfected with the microRNA. RT-PCR for Bcl-2 expression showed that Bcl-2 is down-regulated for miR-375 inhibitor and up-regulated for the miR-375 mimic, a result confirmed by Western blotting.
Conclusion: The present study brings to the forefront new data that suggest miR-375 as a new player in controlling the pathways responsible for inhibiting the natural history of CRC tumor cells, via the Bcl-2 pathway.
Abbreviations: APC: adenomatous polyposis coli; CRC: colorectal cancer; EGFR: epidermal growth factor receptor; ERB: Erythroblastic Leukemia Viral Oncogene Homolog; FITC: Fluorescein isothiocyanate; MAPK: mitogen-activated protein-kinase; miR: microRNA; mTOR: mammalian target of rapamycin; NSM: non specific mimic; qRT-PCR: quantitative real time polymerase chain reaction; SEM: scanning electron microscopy; TEM: transmission electron microscopy; TGF-beta: transforming growth factor beta.