julilili42/papers huggingface dataset:
Bridging the Gap between Pentacene and Perfluoropentacene: Synthesis and Characterization of 2,3,9,10-Tetrafluoropentacene in the Neutral, Cationic, and Dicationic States
2018-02-27

The thermal and photochemical syntheses of 2,3,9,10-tetrafluoropentacene (F4PEN) from 6,13-etheno bridged precursors were investigated computationally and experimentally. A computational study of the retro-Diels-Alder reaction to give 2,3,9,10-tetrasubstituted pentacenes and pyridazine revealed a linear correlation between barrier height and substituent constant (σ<sub>p</sub>) indicative of an electronic effect that could diminish the yield of electron-poor 2,3,9,10-tetrasubstituted pentacenes in this reaction. The photochemical route from the corresponding bridged α-diketone yields F4PEN, which was characterized photophysically, electrochemically, and structurally. The compound crystallizes in a herringbone motif with quite short intermolecular F-F contacts that are, however, only very weakly bonding according to computations. The electrochemical and photophysical data show that the HOMO-LUMO gap of F4PEN is increased compared to that of PEN. This is due to an increase of the oxidation potential of F4PEN by 0.18 V in combination with an essentially unchanged reduction potential. The radical cation and dication of F4PEN could be generated in oxidizing solvents and characterized by optical spectroscopy and ESR or NMR, respectively. Both charged F4PEN species persist for days in solution.
Insights into Carbon Metabolism Provided by FluorescenceIn SituHybridization-Secondary Ion Mass Spectrometry Imaging of an Autotrophic, Nitrate-Reducing, Fe(II)-Oxidizing Enrichment Culture
2018-02-27

ABSTRACT The enrichment culture KS is one of the few existing autotrophic, nitrate-reducing, Fe(II)-oxidizing cultures that can be continuously transferred without an organic carbon source. We used a combination of catalyzed amplification reporter deposition fluorescence in situ hybridization (CARD-FISH) and nanoscale secondary ion mass spectrometry (NanoSIMS) to analyze community dynamics, single-cell activities, and interactions among the two most abundant microbial community members (i.e., Gallionellaceae sp. and Bradyrhizobium spp.) under autotrophic and heterotrophic growth conditions. CARD-FISH cell counts showed the dominance of the Fe(II) oxidizer Gallionellaceae sp. under autotrophic conditions as well as of Bradyrhizobium spp. under heterotrophic conditions. We used NanoSIMS to monitor the fate of 13 C-labeled bicarbonate and acetate as well as 15 N-labeled ammonium at the single-cell level for both taxa. Under autotrophic conditions, only the Gallionellaceae sp. was actively incorporating 13 C-labeled bicarbonate and 15 N-labeled ammonium. Interestingly, both Bradyrhizobium spp. and Gallionellaceae sp. became enriched in [ 13 C]acetate and [ 15 N]ammonium under heterotrophic conditions. Our experiments demonstrated that Gallionellaceae sp. was capable of assimilating [ 13 C]acetate while Bradyrhizobium spp. were not able to fix CO 2 , although a metagenomics survey of culture KS recently revealed that Gallionellaceae sp. lacks genes for acetate uptake and that the Bradyrhizobium sp. carries the genetic potential to fix CO 2 . The study furthermore extends our understanding of the microbial reactions that interlink the nitrogen and Fe cycles in the environment. IMPORTANCE Microbial mechanisms by which Fe(II) is oxidized with nitrate as the terminal electron acceptor are generally referred to as “nitrate-dependent Fe(II) oxidation” (NDFO). NDFO has been demonstrated in laboratory cultures (such as the one studied in this work) and in a variety of marine and freshwater sediments. Recently, the importance of NDFO for the transport of sediment-derived Fe in aquatic ecosystems has been emphasized in a series of studies discussing the impact of NDFO for sedimentary nutrient cycling and redox dynamics in marine and freshwater environments. In this article, we report results from an isotope labeling study performed with the autotrophic, nitrate-reducing, Fe(II)-oxidizing enrichment culture KS, which was first described by Straub et al. (1) about 20 years ago. Our current study builds on the recently published metagenome of culture KS (2).
Bisphosphonate-Linked TrkB Agonist: Cochlea-Targeted Delivery of a Neurotrophic Agent as a Strategy for the Treatment of Hearing Loss
2018-02-27

Hearing loss affects more than two-thirds of the elderly population, and more than 17% of all adults in the U.S. Sensorineural hearing loss related to noise exposure or aging is associated with loss of inner ear sensory hair cells (HCs), cochlear spiral ganglion neurons (SGNs), and ribbon synapses between HCs and SGNs, stimulating intense interest in therapies to regenerate synaptic function. 7,8-Dihydroxyflavone (DHF) is a selective and potent agonist of tropomyosin receptor kinase B (TrkB) and protects the neuron from apoptosis. Despite evidence that TrkB agonists can promote survival of SGNs, local delivery of drugs such as DHF to the inner ear remains a challenge. We previously demonstrated in an animal model that a fluorescently labeled bisphosphonate, 6-FAM-Zol, administered to the round window membrane penetrated the membrane and diffused throughout the cochlea. Given their affinity for bone mineral, including cochlear bone, bisphosphonates offer an intriguing modality for targeted delivery of neurotrophic agents to the SGNs to promote survival, neurite outgrowth, and, potentially, regeneration of synapses between HCs and SGNs. The design and synthesis of a bisphosphonate conjugate of DHF (Ris-DHF) is presented, with a preliminary evaluation of its neurotrophic activity. Ris-DHF increases neurite outgrowth in vitro, maintains this ability after binding to hydroxyapatite, and regenerates synapses in kainic acid-damaged cochlear organ of Corti explants dissected in vitro with attached SGNs. The results suggest that bisphosphonate-TrkB agonist conjugates have promise as a novel approach to targeted delivery of drugs to treat sensorineural hearing loss.
Developing an intervention to overcome procrastination
2018-02-27

The main goal of this study was the development of a reliable intervention to overcome general procrastination orientated to college students, designed to be used in practical clinical work. The workshops involved six meetings based on behavioral and cognitive techniques, paradox intervention, and psychoeducation. 175 students participated voluntarily. Their procrastination levels were measured in a pretest, post-test, and a 3-month follow-up. After the first interview, the participants were randomly divided into three groups (Intervention A, Intervention B, and a control group with no intervention). There was a significant improvement after the intervention. After 3 months, the average score was still significantly lower than in the pretest, whereas the score of the control group remained unchanged. The participants in Workshop A scored significantly lower in the post-test than the ones in Workshop B. After 3 months, the participants in Workshop B scored significantly lower in the follow up. So both interventions resulted to be effective in reducing procrastination sustainably.
The H.E.S.S. Galactic plane survey
2018-02-28

We present the results of the most comprehensive survey of the Galactic plane in very high-energy (VHE) γ -rays, including a public release of Galactic sky maps, a catalog of VHE sources, and the discovery of 16 new sources of VHE γ -rays. The High Energy Spectroscopic System (H.E.S.S.) Galactic plane survey (HGPS) was a decade-long observation program carried out by the H.E.S.S. I array of Cherenkov telescopes in Namibia from 2004 to 2013. The observations amount to nearly 2700 h of quality-selected data, covering the Galactic plane at longitudes from l = 250° to 65° and latitudes | b |≤ 3°. In addition to the unprecedented spatial coverage, the HGPS also features a relatively high angular resolution (0.08° ≈ 5 arcmin mean point spread function 68% containment radius), sensitivity (≲1.5% Crab flux for point-like sources), and energy range (0.2–100 TeV). We constructed a catalog of VHE γ -ray sources from the HGPS data set with a systematic procedure for both source detection and characterization of morphology and spectrum. We present this likelihood-based method in detail, including the introduction of a model component to account for unresolved, large-scale emission along the Galactic plane. In total, the resulting HGPS catalog contains 78 VHE sources, of which 14 are not reanalyzed here, for example, due to their complex morphology, namely shell-like sources and the Galactic center region. Where possible, we provide a firm identification of the VHE source or plausible associations with sources in other astronomical catalogs. We also studied the characteristics of the VHE sources with source parameter distributions. 16 new sources were previously unknown or unpublished, and we individually discuss their identifications or possible associations. We firmly identified 31 sources as pulsar wind nebulae (PWNe), supernova remnants (SNRs), composite SNRs, or gamma-ray binaries. Among the 47 sources not yet identified, most of them (36) have possible associations with cataloged objects, notably PWNe and energetic pulsars that could power VHE PWNe.
Association of health literacy with health information‐seeking preference in older people: A correlational, descriptive study
2018-02-28

Abstract Low health literacy has been recognized as a potential barrier to obtaining knowledge and maintaining self‐care in older people. However, little is known about information‐seeking preference in relation to health literacy among older people. The aim of the present study was to understand the influence of health literacy on the information‐seeking preference of older people. A total of 129 community‐residing Korean older people completed a survey in 2016. The findings revealed that health literacy was a significant predictor of information‐seeking preference in older people after controlling for demographic and illness variables. Our study highlights the important need to incorporate strategies to increase the desire for information seeking in older people, in addition to adopting communication strategies that address low health literacy.
Impact and change of attitudes toward Internet interventions within a randomized controlled trial on individuals with depression symptoms
2018-02-28

Internet interventions may be the most beneficial for individuals with positive attitudes toward them. Informing potential users about evidence-based Internet interventions might instill positive attitudes and thereby optimize the benefits such interventions can provide. Assessing attitudes prior to treatment might help identify suitable users.
The LRRK2 Variant E193K Prevents Mitochondrial Fission Upon MPP+ Treatment by Altering LRRK2 Binding to DRP1
2018-02-28

Mutations in leucine-rich repeat kinase 2 gene (<i>LRRK2</i>) are associated with familial and sporadic Parkinson's disease (PD). LRRK2 is a complex protein that consists of multiple domains, including 13 putative armadillo-type repeats at the N-terminus. In this study, we analyzed the functional and molecular consequences of a novel variant, E193K, identified in an Italian family. E193K substitution does not influence LRRK2 kinase activity. Instead it affects LRRK2 biochemical properties, such as phosphorylation at Ser935 and affinity for 14-3-3ε. Primary fibroblasts obtained from an E193K carrier demonstrated increased cellular toxicity and abnormal mitochondrial fission upon 1-methyl-4-phenylpyridinium treatment. We found that E193K alters LRRK2 binding to DRP1, a crucial mediator of mitochondrial fission. Our data support a role for LRRK2 as a scaffolding protein influencing mitochondrial fission.
Plasma kallikrein activates the epithelial sodium channel in vitro but is not essential for volume retention in nephrotic mice
2018-02-28

Abstract Aim Recent work has demonstrated that activation of the epithelial sodium channel ( EN aC) by aberrantly filtered serine proteases causes sodium retention in nephrotic syndrome. The aim of this study was to elucidate a potential role of plasma kallikrein ( PKLK ) as a candidate serine protease in this context. Methods We analysed PKLK in the urine of patients with chronic kidney disease ( CKD , n = 171) and investigated its ability to activate human EN aC expressed in Xenopus laevis oocytes. Moreover, we studied sodium retention in PKLK ‐deficient mice ( klkb1 −/− ) with experimental nephrotic syndrome induced by doxorubicin injection. Results In patients with CKD , we found that PKLK is excreted in the urine up to a concentration of 2 μg mL −1 which was correlated with albuminuria ( r = .71) and overhydration as assessed by bioimpedance spectroscopy ( r = .44). PKLK increased EN aC‐mediated whole‐cell currents, which was associated with the appearance of a 67 kDa γ‐ EN aC cleavage product at the cell surface consistent with proteolytic activation. Mutating a putative prostasin cleavage site in γ‐ EN aC prevented channel stimulation by PKLK . In a mouse model for nephrotic syndrome, active PKLK was present in nephrotic urine of klkb1 +/+ but not of klkb1 −/− mice. However, klkb1 −/− mice were not protected from EN aC activation and sodium retention compared to nephrotic klkb1 +/+ mice. Conclusion Plasma kallikrein is detected in the urine of proteinuric patients and mice and activates EN aC in vitro involving the putative prostasin cleavage site. However, PKLK is not essential for volume retention in nephrotic mice.
Black Sea outflow response to Holocene meltwater events
2018-02-28

Abstract During the Holocene, North American ice sheet collapse and rapid sea-level rise reconnected the Black Sea with the global ocean. Rapid meltwater releases into the North Atlantic and associated climate change arguably slowed the pace of Neolithisation across southeastern Europe, originally hypothesized as a catastrophic flooding that fueled culturally-widespread deluge myths. However, we currently lack an independent record linking the timing of meltwater events, sea-level rise and environmental change with the timing of Neolithisation in southeastern Europe. Here, we present a sea surface salinity record from the Northern Aegean Sea indicative of two meltwater events at ~8.4 and ~7.6 kiloyears that can be directly linked to rapid declines in the establishment of Neolithic sites in southeast Europe. The meltwater events point to an increased outflow of low salinity water from the Black Sea driven by rapid sea level rise &gt;1.4 m following freshwater outbursts from Lake Agassiz and the final decay of the Laurentide ice sheet. Our results shed new light on the link between catastrophic sea-level rise and the Neolithisation of southeastern Europe, and present a historical example of how coastal populations could have been impacted by future rapid sea-level rise.
Continuous Hepatic Arterial Multiphase Magnetic Resonance Imaging During Free-Breathing
2018-02-28

Purpose The aim of this study was to evaluate the feasibility of a prototype volume-interpolated breath-hold examination (VIBE) sequence using compressed sensing (VIBE CS ) for rapid multiphase arterial magnetic resonance imaging (MRI) at different temporal resolution during free-breathing in comparison with a conventional breath-hold approach (VIBE STD ). Material and Methods A total of 40 patients with liver malignancies were prospectively included in this study and underwent contrast-enhanced liver MRI at 1.5 T to evaluate the performance of VIBE CS for rapid arterial multiphase imaging. An additional 40 patients examined with a VIBE STD were included serving as standard of reference. The VIBE CS study cohort was subdivided into 2 groups (each n = 20). In both groups, VIBE CS was continuously acquired for 60 seconds starting with the contrast agent administration (group A, temporal resolution 4 seconds; group B, temporal resolution 8 seconds). Subsequently, the time point with the subjectively best image quality was selected and defined as hepatic arterial dominant (HAD) phase. Overall image quality, lesion conspicuity, vessel contrast, and artifacts of HAD phase were assessed by 2 radiologists independently on a 5-point Likert scale (5 = excellent) and compared with arterial phase images of VIBE STD . In addition, signal attenuation/time curves of VIBE CS were plotted for each patient to quantify the hepatic arterial enhancement. Results No patients were excluded and all HAD phases were reliably recorded in the investigated VIBE CS cohort. Most commonly, HAD was observed at the ninth time point (36 seconds after intravenous contrast injection) in group A and at the fifth time point (40 seconds after intravenous contrast injection) in group B. Timing with VIBE STD was only adequate in 65% (26/40). Image quality, lesion conspicuity, and vessel contrast were good to excellent without significant differences between both VIBE CS groups ( P ≥ 0.2) and with significantly higher reading scores as compared with VIBE STD with respect to lesion conspicuity ( P ≤ 0.006) and image quality (group B; P &lt; 0.001). VIBE CS showed reconstruction artifacts, which were significantly higher in group A ( P = 0.001). Mean peak arterial enhancement was observed at the ninth time point (36 seconds) in group A and at the sixth (48 seconds) in group B. Conclusion VIBE CS allows for robust multiphase arterial imaging during free-breathing at high spatial and temporal resolution (preferably 8 seconds) with improved image quality and lesion conspicuity as compared with VIBE STD .
Positioning a Novel Transcutaneous Bone Conduction Hearing Implant: a Systematic Anatomical and Radiological Study to Standardize the Retrosigmoid Approach, Correlating Navigation-guided, and Landmark-based Surgery
2018-02-28

Hypothesis: Anatomical and radiological evaluation improves safety and accuracy of the retrosigmoid approach for positioning a transcutaneous bone conduction implant and provides anatomical reference data for standardized, landmark-based implantation at this alternative site. Background: The primary implantation site for the floating mass transducer of a novel bone conduction hearing implant is the mastoid. However, anatomical limitations or previous mastoid surgery may prevent mastoid implantation. Therefore, the retrosigmoid approach has been introduced as an alternative. Methods: Mastoid and retrosigmoid implantation sites were radiologically identified and evaluated in preoperative computed tomography scans of anatomical head specimens. Navigation-guided implantation was then performed in the retrosigmoid site (n = 20). The optimal retrosigmoid position was determined in relation to both the asterion and the mastoid notch as surgical landmarks in an anatomical coordinate system. Results: Preoperative radiological analysis revealed spatial limitations in the mastoid in 45% of the specimens. Navigation-guided retrosigmoid implantation was possible without affecting the sigmoid sinus in all the specimens. The optimal implantation site was located 1.9 ± 0.1 cm posterior/1.7 ± 0.1 cm inferior to the asterion and 3.3 ± 0.2 cm posterior/2.1 ± 0.1 cm superior to the mastoid notch. Retrosigmoid skull thickness was 6.6 ± 0.4 mm, measured anatomically, 7.0 ± 0.4 mm, measured radiologically and 6.7 ± 0.5 mm, measured with the navigation software. Conclusion: The navigation-guided retrosigmoid approach seemed to be a reliable procedure in all the specimens. Measurements of bone thickness revealed the need for spacers in 95% of the specimens. Reference coordinates of the optimal implantation site are provided and can confirm image-guided surgery or facilitate orientation if a navigation system is not available.
Phenotypic Multiorgan Involvement of Subclinical Disease as Quantified by Magnetic Resonance Imaging in Subjects With Prediabetes, Diabetes, and Normal Glucose Tolerance
2018-02-28

Introduction Detailed mechanisms in the pathophysiology of diabetes disease are poorly understood, but structural alterations in various organ systems incur an elevated risk for cardiovascular events and adverse outcome. The aim of this study was to compare multiorgan subclinical disease phenotypes by magnetic resonance (MR) imaging to study differences between subjects with prediabetes, diabetes, and normal controls. Materials and Methods Subjects without prior cardiovascular disease were enrolled in a prospective case-control study and underwent multiorgan MR for the assessment of metabolic and arteriosclerotic alterations, including age-related white matter changes, hepatic proton density fat fraction, visceral adipose tissue volume, left ventricular remodeling index, carotid plaque, and late gadolinium enhancement. Magnetic resonance features were summarized in a phenotypic-based score (range, 0–6). Univariate, multivariate correlation, and unsupervised clustering were performed. Results Among 243 subjects with complete multiorgan MR data sets included in the analysis (55.6 ± 8.9 years, 62% males), 48 were classified as subjects with prediabetes and 38 as subjects with diabetes. The MR phenotypic score was significantly higher in subjects with prediabetes and diabetes as compared with controls (mean score, 3.00 ± 1.04 and 2.69 ± 0.98 vs 1.22 ± 0.98, P &lt; 0.001 respectively), also after adjustment for potential confounders. We identified 2 clusters of MR phenotype patterns associated with glycemic status ( P &lt; 0.001), independent of the MR score (cluster II–metabolic specific: odds ratio, 2.49; 95% CI, 1.00–6.17; P = 0.049). Discussion Subjects with prediabetes and diabetes have a significantly higher phenotypic-based score with a distinctive multiorgan phenotypic pattern, which may enable improved disease characterization.
Draft Genome Sequence of Streptomyces sp. Strain DH-12, a Soilborne Isolate from the Thar Desert with Broad-Spectrum Antibacterial Activity
2018-02-28

ABSTRACT Strain DH-12 exhibits broad-spectrum antibacterial activity toward Gram-positive and Gram-negative pathogens. The 7.6-Mb draft genome sequence gives insight into the complete secondary metabolite production capacity and reveals genes putatively responsible for its antibacterial activity, as well as genes which enable the survival of the organism in an extreme arid environment.
Dopamine Receptors Influence Internally Generated Oscillations during Rule Processing in Primate Prefrontal Cortex
2018-02-28

Neural oscillations in distinct frequency bands in the prefrontal cortex (pFC) are associated with specialized roles during cognitive control. How dopamine modulates oscillations to structure pFC functions remains unknown. We trained macaques to switch between two numerical rules and recorded local field potentials from pFC while applying dopamine receptor targeting drugs using microiontophoresis. We show that the D1 and D2 family receptors (D1Rs and D2Rs, respectively) specifically altered internally generated prefrontal oscillations, whereas sensory-evoked potentials remained unchanged. Blocking D1Rs or stimulating D2Rs increased low-frequency theta and alpha oscillations known to be involved in learning and memory. In contrast, only D1R inhibition enhanced high-frequency beta oscillations, whereas only D2R stimulation increased gamma oscillations linked to top–down and bottom–up attentional processing. These findings suggest that dopamine alters neural oscillations relevant for executive functioning through dissociable actions at the receptor level.