bluuebunny/crossref_metadata_2025_split huggingface dataset:
Elucidating a role for the cytoplasmic domain in the Mycobacterium tuberculosis mechanosensitive channel of large conductance
Authors: Herrera Nadia , Maksaev Grigory , Haswell Elizabeth S. , Rees Douglas C. 
Published: September 2018

AbstractMicrobial survival in dynamic environments requires the ability to successfully respond to abrupt changes in osmolarity. The mechanosensitive channel of large conductance (MscL) is a ubiquitous channel that facilitates the survival of bacteria and archaea under severe osmotic downshock conditions by relieving excess turgor pressure in response to increased membrane tension. A prominent structural feature of MscL, the cytoplasmic C-terminal domain, has been suggested to influence channel assembly and function. In this report, we describe the X-ray crystal structure and electrophysiological properties of a C-terminal domain truncation of the Mycobacterium tuberculosis MscL (MtMscLΔC). A crystal structure of MtMscLΔC solubilized in the detergent n-dodecyl-β-D-maltopyranoside reveals the pentameric, closed state-like architecture for the membrane spanning region observed in the previously solved full-length MtMscL. Electrophysiological characterization demonstrates that MtMscLΔC retains mechanosensitivity, but with conductance and tension sensitivity more closely resembling full length EcMscL than MtMscL. This study establishes that the C-terminal domain of MtMscL is not required for oligomerization of the full-length channel, but rather influences the tension sensitivity and conductance properties of the channel. The collective picture that emerges from these data is that each MscL channel structure has characteristic features, highlighting the importance of studying multiple homologs.
Competition and dual users in complex contagion processes
Authors: Min Byungjoon , San Miguel Maxi 
Published: September 2018

AbstractWe study the competition of two spreading entities, for example innovations, in complex contagion processes in complex networks. We develop an analytical framework and examine the role of dual users, i.e. agents using both technologies. Searching for the spreading transition of the new innovation and the extinction transition of a preexisting one, we identify different phases depending on network mean degree, prevalence of preexisting technology, and thresholds of the contagion process. Competition with the preexisting technology effectively suppresses the spread of the new innovation, but it also allows for phases of coexistence. The existence of dual users largely modifies the transient dynamics creating new phases that promote the spread of a new innovation and extinction of a preexisting one. It enables the global spread of the new innovation even if the old one has the first-mover advantage.
Experimental evidence for the enhanced and reduced stopping regimes for protons propagating through hot plasmas
Authors: Chen S. N. , Atzeni S. , Gangolf T. , Gauthier M. , Higginson D. P. , Hua R. , Kim J. , Mangia F. , McGuffey C. , Marquès J.-R. , Riquier R. , Pépin H. , Shepherd R. , Willi O. , Beg F. N. , Deutsch C. , Fuchs J. 
Published: September 2018

AbstractOur understanding of the dynamics of ion collisional energy loss in a plasma is still not complete, in part due to the difficulty and lack of high-quality experimental measurements. These measurements are crucial to benchmark existing models. Here, we show that such a measurement is possible using high-flux proton beams accelerated by high intensity short pulse lasers, where there is a high number of particles in a picosecond pulse, which is ideal for measurements in quickly expanding plasmas. By reducing the energy bandwidth of the protons using a passive selector, we have made proton stopping measurements in partially ionized Argon and fully ionized Hydrogen plasmas with electron temperatures of hundreds of eV and densities in the range 1020–1021 cm−3. In the first case, we have observed, consistently with previous reports, enhanced stopping of protons when compared to stopping power in non-ionized gas. In the second case, we have observed for the first time the regime of reduced stopping, which is theoretically predicted in such hot and fully ionized plasma. The versatility of these tunable short-pulse laser based ion sources, where the ion type and energy can be changed at will, could open up the possibility for a variety of ion stopping power measurements in plasmas so long as they are well characterized in terms of temperature and density. In turn, these measurements will allow tests of the validity of existing theoretical models.
Relationship between mean platelet volume and metabolic syndrome in Chinese patients
Authors: Zhao Fengxiao , Yan Ziyu , Meng Zhaowei , Li Xue , Liu Ming , Ren Xiaojun , Zhu Mei , He Qing , Zhang Qing , Song Kun , Jia Qiyu , Zhang Chunmei , Wang Huiying , Liu Xiaoxia , Zhang Xuemei , Wang Xiaoran , Pan Zhengzhou , Liu Xiangxiang , Zhang Wan 
Published: September 2018

AbstractMean platelet volume (MPV) is a determinant of activation and variability of platelets (PLT). The focus of this study was to to investigate MPV values in patients with and without metabolic syndrome (MS). It also evaluates the association between them. There are close connections among MPV, MS, and cardiometabolic risk. We compiled age, body mass index, blood cell counts, MPV, and other data of 59976 self-reported healthy volunteers (28428 male, 31548 female), 24.65% of who have MS. The mean age of the group was 48.21 years old. The data was grouped by sex and values of data between men and women groups were analyzed by independent sample’s t-test. The relationship between sex and MS was evaluated by chi-square tests. Crude odd ratios of MS between MPV quartiles and 95% confidence intervals were analyzed by binary logistic regression in this study. We found women had higher levels of MPV (10.09 vs. 9.98, P < 0.01) and PLT (228.68 vs. 212.11, P < 0.01) than men. In females, the prevalence of MS was higher in low MPV group than in high MPV groups. The odds of having MS were significantly lower in higher MPV quartiles compared with MPV Quartile 1 in women (Adjusted OR < 1, P < 0.01). This study indicated that MS was inversely associated with MPV in females only.
Small-molecule AgrA inhibitors F12 and F19 act as antivirulence agents against Gram-positive pathogens
Authors: Greenberg Michael , Kuo David , Jankowsky Eckhard , Long Lisa , Hager Chris , Bandi Kiran , Ma Danyang , Manoharan Divya , Shoham Yaron , Harte William , Ghannoum Mahmoud A. , Shoham Menachem 
Published: September 2018

AbstractSmall-molecule antivirulence agents represent a promising alternative or adjuvant to antibiotics. These compounds disarm pathogens of disease-causing toxins without killing them, thereby diminishing survival pressure to develop resistance. Here we show that the small-molecule antivirulence agents F12 and F19 block staphylococcal transcription factor AgrA from binding to its promoter. Consequently, toxin expression is inhibited, thus preventing host cell damage by Gram-positive pathogens. Broad spectrum efficacy against Gram-positive pathogens is due to the existence of AgrA homologs in many Gram-positive bacteria. F12 is more efficacious in vitro and F19 works better in vivo. In a murine MRSA bacteremia/sepsis model, F19 treatment alone resulted in 100% survival while untreated animals had 70% mortality. Furthermore, F19 enhances antibiotic efficacy in vivo. Notably, in a murine MRSA wound infection model, combination of F19 with antibiotics resulted in bacterial load reduction. Thus, F19 could be used alone or in combination with antibiotics to prevent and treat infections of Gram-positive pathogens.
Transcriptome Analysis of Intrusively Growing Flax Fibers Isolated by Laser Microdissection
Authors: Gorshkova Tatyana , Chernova Tatyana , Mokshina Natalia , Gorshkov Vladimir , Kozlova Liudmila , Gorshkov Oleg 
Published: September 2018

AbstractThe intrusive growth, a type of plant cell elongation occurring in the depths of plant tissues, is characterized by the invasion of a growing cell between its neighbours due to a higher rate of elongation. In order to reveal the largely unknown molecular mechanisms of intrusive growth, we isolated primary flax phloem fibers specifically at the stage of intrusive growth by laser microdissection. The comparison of the RNA-Seq data from several flax stem parts enabled the characterization of those processes occurring specifically during the fiber intrusive elongation. The revealed molecular players are summarized as those involved in the supply of assimilates and support of turgor pressure, cell wall enlargement and modification, regulation by transcription factors and hormones, and responses to abiotic stress factors. The data obtained in this study provide a solid basis for developing approaches to manipulate fiber intrusive elongation, which is of importance both for plant biology and the yield of fiber crops.
The prevalence of olfactory- versus visual-signal encounter by searching bumblebees
Authors: Sprayberry Jordanna D. H. 
Published: September 2018

AbstractWhile the phrase ‘foraging bumblebee’ brings to mind a bumbling bee flying flower to flower in a sunny meadow, foraging is a complicated series of behaviors such as: locating a floral patch; selecting a flower-type; learning handling skills for pollen and nectar extraction; determining when to move-on from a patch; learning within-patch paths (traplining); and learning efficient hive-to-patch routes (spatial navigation). Thus the term ‘forager’ encompasses multiple distinct behaviors that rely on different sensory modalities. Despite a robust literature on bumblebee foraging behavior, few studies are directly relevant to sensory-guided search; i.e. how workers locate novel patches. The first step in answering this question is to determine what sensory information is available to searching bumblebees. This manuscript presents a computational model that elucidates the relative frequency of visual and olfactory cues that are available to workers searching for floral resources under a range of ecologically relevant scenarios. Model results indicate that odor is the most common sensory cue encountered during search flights. When the likelihood of odor-plume contact is higher, odor-encounter is ubiquitous. While integrative (visual + olfactory) cues are common when foragers are searching for larger flowers (e.g. Echinacea), they become rare when foragers are searching for small flowers (e.g. Penstemon). Visual cues are only encountered in isolation when foragers are seeking large flowers with a low odor-plume contact probability. These results indicate that despite the multisensory nature of floral signals, different modalities may be encountered in isolation during search-behavior, as opposed to the reliably multimodal signals encountered during patch-exploitation or nectar/ pollen acquisition.
Calcium increases titin N2A binding to F-actin and regulated thin filaments
Authors: Dutta Samrat , Tsiros Christopher , Sundar Sai Lavanyaa , Athar Humra , Moore Jeffrey , Nelson Brent , Gage Matthew J. , Nishikawa Kiisa 
Published: September 2018

AbstractMutations in titin are responsible for many cardiac and muscle diseases, yet the underlying mechanisms remain largely unexplained. Numerous studies have established roles for titin in muscle function, and Ca2+-dependent interactions between titin and actin have been suggested to play a role in muscle contraction. The present study used co-sedimentation assays, dynamic force spectroscopy (DFS), and in vitro motility (IVM) assays to determine whether the N2A region of titin, overlooked in previous studies, interacts with actin in the presence of Ca2+. Co-sedimentation demonstrated that N2A – F-actin binding increases with increasing protein and Ca2+ concentration, DFS demonstrated increased rupture forces and decreased koff in the presence of Ca2+, and IVM demonstrated a Ca2+-dependent reduction in motility of F-actin and reconstituted thin filaments in the presence of N2A. These results indicate that Ca2+ increases the strength and stability of N2A – actin interactions, supporting the hypothesis that titin plays a regulatory role in muscle contraction. The results further support a model in which N2A – actin binding in active muscle increases titin stiffness, and that impairment of this mechanism contributes to the phenotype in muscular dystrophy with myositis. Future studies are required to determine whether titin – actin binding occurs in skeletal muscle sarcomeres in vivo.
Leukocyte telomere length and risk of gastric cardia adenocarcinoma
Authors: Liu Yang , Lei Tianshui , Zhang Nasha , Zheng Yan , Kou Peisi , Shang Shuheng , Yang Ming 
Published: September 2018

AbstractAs a chromosome stabilizer, telomeres play an essential part in maintaining the stability and integrity of human genome. Shortened telomeres have been associated with the development of cancers but it is still largely unclear whether leukocyte telomere length contributes to predisposition of gastric cardia adenocarcinoma (GCA). We conducted a case-control study consisting of 524 GCA cases and 510 controls to assess the association between telomere length in peripheral blood leukocytes and GCA risk in a Chinese Han population. The GCA patients had significantly overall shorter relative leukocyte telomere length (RTL) (median ± SD: 1.10 ± 0.54) when compared with the controls (1.24 ± 0.58). Individuals with the shortest quartile of RTL performed a doubled GCA risk (OR = 2.18; 95% CI = 1.47–3.22, P = 9.90 × 10−5) when compared with those with the highest quartile. We also found that telomere shortening and smoking have a significantly synergistic effect in intensifying risk of GCA (OR = 7.03, 95% CI = 4.55–10.86, P = 1.43 × 10−18). These findings indicate that short RTL contributes to increased susceptibility of gastric cardia adenocarcinoma and might be a promising marker to identify high-risk individuals combined with lifestyle risk factors.
Pinopsin evolved as the ancestral dim-light visual opsin in vertebrates
Authors: Sato Keita , Yamashita Takahiro , Kojima Keiichi , Sakai Kazumi , Matsutani Yuki , Yanagawa Masataka , Yamano Yumiko , Wada Akimori , Iwabe Naoyuki , Ohuchi Hideyo , Shichida Yoshinori 
Published: September 2018

AbstractPinopsin is the opsin most closely related to vertebrate visual pigments on the phylogenetic tree. This opsin has been discovered among many vertebrates, except mammals and teleosts, and was thought to exclusively function in their brain for extraocular photoreception. Here, we show the possibility that pinopsin also contributes to scotopic vision in some vertebrate species. Pinopsin is distributed in the retina of non-teleost fishes and frogs, especially in their rod photoreceptor cells, in addition to their brain. Moreover, the retinal chromophore of pinopsin exhibits a thermal isomerization rate considerably lower than those of cone visual pigments, but comparable to that of rhodopsin. Therefore, pinopsin can function as a rhodopsin-like visual pigment in the retinas of these lower vertebrates. Since pinopsin diversified before the branching of rhodopsin on the phylogenetic tree, two-step adaptation to scotopic vision would have occurred through the independent acquisition of pinopsin and rhodopsin by the vertebrate lineage.
Generation and characterization of thiol-deficient Mycobacterium tuberculosis mutants
Authors: Sao Emani C. , Williams M. J. , Van Helden P. D. , Taylor M. J. C. , Carolis C. , Wiid I. J. , Baker B. 
Published: September 2018

AbstractMycothiol (MSH) and ergothioneine (ERG) are thiols able to compensate for each other to protect mycobacteria against oxidative stress. Gamma-glutamylcysteine (GGC), another thiol and an intermediate in ERG biosynthesis has detoxification abilities. Five enzymes are involved in ERG biosynthesis, namely EgtA, EgtB, EgtC, EgtD and EgtE. The role of these enzymes in the production of ERG had been unclear. On the other hand, the enzyme MshA is known to be essential for MSH biosynthesis. In this manuscript, we describe the raw data of the generation and characterization ofMycobacterium tuberculosis(M.tb)mutants harbouring a deletion of the gene coding for each of these enzymes, and the raw data of the phenotypic characterization of the obtained thiol-deficientM.tbmutants. High throughput screening (HTS) of off-patent drugs and natural compounds revealed few compounds that displayed a higher activity against the thiol-deficient mutants relative to the wild-type strain. The mode of action of these drugs was further investigated. Raw data displaying these results are described here.
Mimi-PAGE, an open-source implementation of the PAGE09 integrated assessment model
Authors: Moore Frances C. , Rising James , Lollo Niklas , Springer Cecilia , Vasquez Valeri , Dolginow Alex , Hope Chris , Anthoff David 
Published: September 2018

AbstractIntegrated Assessment Models (IAMs) have become critical tools for assessing the costs and benefits of policies to reduce greenhouse gas emissions. Three models currently inform the social cost of carbon dioxide (SCCO2, the net present value of damages from one additional ton of CO2) used by the US federal government, several states, and Canada. Here we present a new open-source implementation of one of these models (PAGE09) in the Julia programming language using a modular modeling framework (Mimi). Mimi-PAGE was coded using best coding practices (such as multiple code reviews by different individuals during development, automated testing of newly-committed code, and provision of documentation and usage notes) and is publicly available in a GitHub repository for community inspection and use under an open source license. In this paper we describe the Julia implementation of PAGE09, show that output from Mimi-PAGE matches that of the original model, and perform comparisons of the run time between the two implementations.
Development of industrial scale PVC nanocomposites with comprehensive enhancement in dielectric properties
Authors: Abdel‐Gawad Nagat M.K. , El Dein Adel Z. , Mansour Diaa‐Eldin A. , Ahmed Hanaa M. , Darwish Mohamed M. F. , Lehtonen Matti 
Published: September 2018

This study aims to develop large‐scale polyvinyl chloride (PVC) nanocomposites for industrial application with power cables. To achieve this goal, PVC/silicon dioxide and PVC/titanium dioxide nanocomposites were fabricated with two different loadings of nanoparticles: 0.3 and 0.6 wt.%, in the presence of a suitable coupling agent that was used to reduce the agglomeration of nanoparticles and enhance the compatibility with polymer matrix. The coupling agent used in this study was the amino silane, and the process followed in the nanocomposites preparation was the melt blending method. The dielectric properties of these synthesised nanocomposites were studied by measuring the AC dielectric breakdown strength under the uniform field, then compared with the simulation results. The relative permittivity (ɛr), loss tangent (tan δ), and DC electrical conductivity (σ) were also measured under frequencies ranging from 20 Hz to 1 MHz. In addition, the internal discharge measurements are performed using the traditional needle‐plane configuration with the help of phase‐resolved partial discharge (PD) analyser. This technique is used to analyse the PDs activity with respect to the phase angle of the applied voltage. It was found that the dielectric breakdown strength and PD resistance of the prepared samples are increased higher than that of the neat PVC; however, the ɛr, tan δ, and σ at 50 Hz are decreased.
Synthetic simulations of the extragalactic sky seen by eROSITA
Authors: Clerc N. , Ramos-Ceja M. E. , Ridl J. , Lamer G. , Brunner H. , Hofmann F. , Comparat J. , Pacaud F. , Käfer F. , Reiprich T. H. , Merloni A. , Schmid C. , Brand T. , Wilms J. , Friedrich P. , Finoguenov A. , Dauser T. , Kreykenbohm I. 
Published: September 2018

Context. Studies of galaxy clusters provide stringent constraints on models of structure formation. Provided that selection effects are under control, large X-ray surveys are well suited to derive cosmological parameters, in particular those governing the dark energy equation of state.
Aims. We forecast the capabilities of the all-sky eROSITA (extended ROentgen Survey with an Imaging Telescope Array) survey to be achieved by the early 2020s. We bring special attention to modelling the entire chain from photon emission to source detection and cataloguing.
Methods. The selection function of galaxy clusters for the upcoming eROSITA mission is investigated by means of extensive and dedicated Monte-Carlo simulations. Employing a combination of accurate instrument characterisation and a state-of-the-art source detection technique, we determine a cluster detection efficiency based on the cluster fluxes and sizes.
Results. Using this eROSITA cluster selection function, we find that eROSITA will detect a total of approximately 105 clusters in the extra-galactic sky. This number of clusters will allow eROSITA to put stringent constraints on cosmological models. We show that incomplete assumptions on selection effects, such as neglecting the distribution of cluster sizes, induce a bias in the derived value of cosmological parameters.
Conclusions. Synthetic simulations of the eROSITA sky capture the essential characteristics impacting the next-generation galaxy cluster surveys and they highlight parameters requiring tight monitoring in order to avoid biases in cosmological analyses.
Star formation history and metallicity in the Galactic inner bulge revealed by the red giant branch bump
Authors: Nogueras-Lara F. , Schödel R. , Dong H. , Najarro F. , Gallego-Calvente A. T. , Hilker M. , Gallego-Cano E. , Nishiyama S. , Neumayer N. , Feldmeier-Krause A. , Girard J. H. V. , Cassisi S. , Pietrinferni A. 
Published: September 2018

Context. The study of the inner region of the Milky Way bulge is hampered by high interstellar extinction and extreme source crowding. Sensitive high angular resolution near-infrared imaging is needed to study stellar populations and their characteristics in such a dense and complex environment.
Aims. We aim at investigating the stellar population in the innermost Galactic bulge, to study the star formation history in this region of the Galaxy.
Methods. We used the 0.2″ angular resolution JHKs data from the GALACTICNUCLEUS survey to study the stellar population within two 8.0′×3.4′ fields, about 0.6° and 0.4° to the Galactic north of the Milky Way centre and to compare it with the one in the immediate surroundings of Sagittarius A*. We also characterise the absolute extinction and the extinction curve of the two fields.
Results. The average interstellar extinction to the outer and the inner field is AKs ∼ 1.20 ± 0.08 mag and ∼1.48 ± 0.10 mag, respectively. We present Ks luminosity functions that are complete down to at least two magnitudes below the red clump (RC). We detect a feature in the luminosity functions that is fainter than the RC by 0.80 ± 0.03 and 0.79 ± 0.02 mag, respectively, in the Ks band. It runs parallel to the reddening vector. We identify the feature as the red giant branch bump. Fitting α-enhanced BaSTI luminosity functions to our data, we find that a single old stellar population of ∼12.8 ± 0.6 Gyr and Z = 0.040 ± 0.003 provides the best fit. Our findings thus show that the stellar population in the innermost bulge is old, similar to the one at larger distances from the Galactic plane, and that its metallicity is about twice solar at distances as short as about 60 pc from the centre of the Milky Way, similar to what is observed at about 500 pc from the Galactic Centre. Comparing the obtained metallicity with previous known values at larger latitudes (|b| > 2°), our results favour a flattening of the gradient at |b| < 2°. As a secondary result we obtain that the extinction index in the studied regions agrees within the uncertainties with our previous value of α = 2.30 ± 0.08 that was derived for the very Galactic centre.