julilili42/papers huggingface dataset:
Exploring Tracer Information and Model Framework Trade‐Offs to Improve Estimation of Stream Transient Storage Processes
2019-03-22

Abstract Novel observation techniques (e.g., smart tracers) for characterizing coupled hydrological and biogeochemical processes are improving understanding of stream network transport and transformation dynamics. In turn, these observations are thought to enable increasingly sophisticated representations within transient storage models (TSMs). However, TSM parameter estimation is prone to issues with insensitivity and equifinality, which grow as parameters are added to model formulations. Currently, it is unclear whether (or not) observations from different tracers may lead to greater process inference and reduced parameter uncertainty in the context of TSM. Herein, we aim to unravel the role of in‐stream processes alongside metabolically active (MATS) and inactive storage zones (MITS) using variable TSM formulations. Models with one (1SZ) and two storage zones (2SZ) and with and without reactivity were applied to simulate conservative and smart tracer observations obtained experimentally for two reaches with differing morphologies. As we show, smart tracers are unsurprisingly superior to conservative tracers when it comes to partitioning MITS and MATS. However, when transient storage is lumped within a 1SZ formulation, little improvement in parameter uncertainty is gained by using a smart tracer, suggesting the addition of observations should scale with model complexity. Importantly, our work identifies several inconsistencies and open questions related to reconciling time scales of tracer observation with conceptual processes (parameters) estimated within TSM. Approaching TSM with multiple models and tracer observations may be key to gaining improved insight into transient storage simulation as well as advancing feedback loops between models and observations within hydrologic science.
Polyacenes and diffuse interstellar bands
2019-03-22

The identification of the carriers of the diffuse interstellar bands (DIBs) remains to be established, with the exception of five bands attributed to C 60 + , although it is generally agreed that DIB carriers should be large carbon-based molecules (with ~10–100 atoms) in the gas phase, such as polycyclic aromatic hydrocarbons (PAHs), long carbon chains or fullerenes. The aim of this paper is to investigate more specific possible carriers among PAHs, namely elongated molecules, which could explain a correlation between the DIB wavelength and the apparent UV resilience of their carriers. More specifically, we address the case of polyacenes, C 4 N +2 H 2 N +4 , with N ~ 10–18 fused rectilinear aligned hexagons. Polyacenes are attractive DIB carrier candidates because their high symmetry and large linear size allow them to form regular series of bands in the visible range with strengths larger than most other PAHs, as confirmed by recent laboratory results up to undecacene (C 46 H 26 ). Those with very strong bands in the DIB spectral domain are just at the limit of stability against UV photodissociation. They are part of the prominent PAH family of interstellar carbon compounds, meaning that only ~10 −5 of the total PAH abundance is enough to account for a medium-strength DIB. After summarizing the limited current knowledge about the complex properties of polyacenes and recent laboratory results, the likelihood that they might meet the criteria for being carriers of some DIBs is addressed by reviewing the following properties: wavelength and strength of their series of visible bands; interstellar stability and abundances, charge state and hydrogenation; and DIB rotation profiles. No definite inconsistency has been identified that precludes polyacenes from being the carriers of some DIBs with medium or weak strength, including the so-called C 2 DIBs. But, despite their many interesting properties, additional experimental data about long acenes and their visible bands are needed to make robust conclusions.
Homozygous stop mutation in AHR causes autosomal recessive foveal hypoplasia and infantile nystagmus
2019-03-22

Herein we present a consanguineous family with three children affected by foveal hypoplasia with infantile nystagmus, following an autosomal recessive mode of inheritance. The patients showed normal electroretinography responses, no signs of albinism, and no anterior segment or brain abnormalities. Upon whole exome sequencing, we identified a homozygous mutation (c.1861C>T;p.Q621*) in the aryl hydrocarbon receptor (AHR) gene that perfectly co-segregated with the disease in the larger family. AHR is a ligand-activated transcription factor that has been intensively studied in xenobiotic-induced toxicity. Further, it has been shown to play a physiological role under normal cellular conditions, such as in immunity, inflammatory response and neurogenesis. Notably, knockout of the Ahr gene in mouse impairs optic nerve myelin sheath formation and results in oculomotor deficits sharing many features with our patients: the eye movement disorder in Ahr-/- mice appears early in development and presents as conjugate horizontal pendular nystagmus. We therefore propose AHR to be a novel disease gene for a new, recessively inherited disorder in humans, characterized by infantile nystagmus and foveal hypoplasia.
Association of Chemerin Plasma Concentration With Risk of Colorectal Cancer
2019-03-22

This study found that the association between chemerin concentration and the risk of incident CRC was linear and independent of established CRC risk factors. Further studies are warranted to evaluate chemerin as a novel immune-inflammatory agent in colorectal carcinogenesis.
CyaC, a redox‐regulated adenylate cyclase of Sinorhizobium meliloti with a quinone responsive diheme‐B membrane anchor domain
2019-03-22

Summary The nucleotide cyclase CyaC of Sinorhizobium meliloti is a member of class III adenylate cyclases (AC), a diverse group present in all forms of life. CyaC is membrane‐integral by a hexahelical membrane domain (6TM) with the basic topology of mammalian ACs. The 6TM domain of CyaC contains a tetra‐histidine signature that is universally present in the membrane anchors of bacterial diheme‐B succinate‐quinone oxidoreductases. Heterologous expression of cyaC imparted activity for cAMP formation from ATP to Escherichia coli, whereas guanylate cyclase activity was not detectable. Detergent solubilized and purified CyaC was a diheme‐B protein and carried a binuclear iron‐sulfur cluster. Single point mutations in the signature histidine residues caused loss of heme‐B in the membrane and loss of AC activity. Heme‐B of purified CyaC could be oxidized or reduced by ubiquinone analogs (Q 0 or Q 0 H 2 ). The activity of CyaC in bacterial membranes responded to oxidation or reduction by Q 0 and O 2 , or NADH and Q 0 H 2 respectively. We conclude that CyaC‐like membrane anchors of bacterial ACs can serve as the input site for chemical stimuli which are translated by the AC into an intracellular second messenger response.
Preexisting musculoskeletal burden and its development under letrozole treatment in early breast cancer patients
2019-03-22

One of the most common adverse events (AEs) occurring during treatment with aromatase inhibitors (AIs) is musculoskeletal pain. The aim of our study was to analyze the influence of preexisting muscle/limb pain and joint pain on the development of AI‐induced musculoskeletal AEs. Women eligible for upfront adjuvant endocrine therapy with letrozole were included in the PreFace study, a multicenter phase IV trial. During the first treatment year, they were asked to record musculoskeletal AEs monthly by answering questions regarding pain symptoms and rating the pain intensity on a numeric rating scale from 0 (no pain) to 10 (very strong pain). Pain values were compared using nonparametric statistical tests. Overall, 1,416 patients were evaluable. The average pain value over all time points in women with preexisting muscle/limb pain was 4.3 (median 4.3); in those without preexisting pain, it was 2.0 (median 1.7). In patients without preexisting muscle/limb pain, pain levels increased relatively strongly within the first 6 months (mean increase +0.9, p &lt; 0.00001) in comparison with those with preexisting pain (mean increase +0.3, p &lt; 0.001), resulting in a statistically significant difference ( p &lt; 0.00001) between the two groups. The development of joint pain was similar in the two groups. Women without preexisting muscle/limb pain or joint pain have the greatest increase in pain after the start of adjuvant AI therapy. Women with preexisting pain have significantly higher pain values. The main increase in pain values takes place during the first 6 months of treatment.
Cross-Codal Integration of Bridging Event Information in Narrative Understanding
2019-03-22

Visual narratives communicate event sequences by using different code systems such as pictures and texts. Thus, comprehenders must integrate information from different codalities. This study addressed such cross-codal integration processes by investigating how the codality of bridging event information (i.e. pictures, text) affects the understanding of visual narrative events. In Experiment 1, bridging event information was either present (as picture or text) or absent (i.e. not shown). The viewing times for the subsequent picture depicting the end state of the action were comparable within the absent and the text conditions. Further, the viewing times for the end state picture were significantly longer in the text condition as compared to the pictorial condition. In Experiment 2, we tested whether replacing bridging event information with a blank panel increases viewing times in a way similar to the text condition. Bridging event information was either present (as picture) or absent (not shown vs. blank panel). The results replicated Experiment 1. Additionally, the viewing times for the end state pictures were longest in the blank condition. In Experiment 3, we investigated the costs related to integrating information from different codalities by directly comparing the text and picture conditions with the blank condition. The results showed that the distortion caused by the blank panel is larger than the distortion caused by cross-codal integration processes. Summarizing, we conclude that cross-codal information processing during narrative comprehension is possible but associated with additional mental effort. We discuss the results with regard to theories of narrative understanding.
Evaluation of Patients' Posture and Gait Profile After Lumbar Fusion Surgery by Video Rasterstereography and Treadmill Gait Analysis
2019-03-23

This protocol provides guidance on how to perform high resolution video rasterstereography and treadmill gait analysis on patients after lumbar fusion surgery to obtain results about altered variables of gait and posture. These observed changes can then be correlated with the patient-reported outcome measure of pain relief. The rasterstereographic device projects lines of parallel light onto the surface of the tested subject's back. The deformation of these lines is recognized by the device. From these data, a special software then generates a 3-D profile based on the principle of triangulation. With an inaccuracy of only 0.2 mm it can measure changes in posture at very high precision. Gait and stance parameters are recorded using a treadmill equipped with an electric sensor mat that contains 10,200 miniature force sensors in the registering zone under the belt. Initial walking speed on the treadmill is 0.5 km/h. Speed is then gradually increased by increments of 0.1 km/h until each subject reaches his or her individual maximum well tolerable walking speed. At this speed, parameters are recorded during a 20 s measurement interval. Subjects are tested barefoot and without holding a handrail. Among various other parameters, stride width, step length, stance phase and foot rotation are measured. Both methods used reportedly have a high intra- and inter-observer reliability. The advantage of these highly accurate techniques is that they offer an objective and very detailed perspective on changes in the patient's posture and gait. Due to the amount of data generated, these techniques are, however, not so much suitable for everyday routine use, but rather interesting to scientifically evaluate long term alterations in posture and gait in patients like for example after lumbar fusion surgery.
Plume‐Induced Breakup of a Subducting Plate: Microcontinent Formation Without Cessation of the Subduction Process
2019-03-25

Abstract Separation of microcontinents is explained by a ridge jump toward the passive margin as a possible consequence of plume‐induced rheological weakening, ultimately leading to breakup followed by accretion of the oceanic crust along a new spreading center. In contrast to such a purely extensional case, the separation of continental microblocks from the main body of the African plate during its continuous northward motion and subduction under Eurasia is still poorly understood. Our numerical experiments show the thermal and buoyancy effects of mantle plume impingement on the bottom of the continental part of a subducting plate are sufficient to induce separation of an isolated microcontinental block from the main subducting continent, even during induced plate motion necessary for uninterrupted oceanic and continental subduction. Subsequent continental accretion occurs by decoupling upper‐crustal nappes from the newly formed subducting microcontinent, which is in agreement with the Late Cretaceous‐Eocene evolution of the eastern Mediterranean.
Threshold resummation at NNLL for single-particle production in hadronic collisions
2019-03-25

We develop threshold resummation for single-particle inclusive cross sections in hadron-hadron collisions to the level of next-to-next-to-leading logarithm, up to full matching with two-loop hard functions. We define and calculate all one-loop soft functions for all partonic channels. This enables us to separate the hard and soft functions at one loop. Along with these results, the one-loop finite parts of jet functions are used to check that the full soft, collinear and virtual corrections are reproduced to one loop for all partonic reactions. We exhibit these NLO results explicitly. NLO expansions of the resummed cross section match the exact NLO results extremely well numerically, and two loop expansions result in substantial corrections over many kinematic configurations. Explicit results are given in Mellin moment space, and a number of options for generating resummed cross sections are discussed.
Signs of enhanced formation of gist memory in children with autism spectrum disorder – a study of memory functions of sleep
2019-03-25

Background Autism spectrum disorder ( ASD ) is characterized by impaired cognitive and social skills, including emotional dysregulation, and symptoms have been suspected to partly arise from impaired formation of memory representations regulating these behaviours. Sleep, which is subjectively impaired in ASD , is critical for forming long‐term memories and abstracted gist‐based representations. We expected a generally reduced memory benefit from sleep in children with ASD , and a diminished enhancement of gist representations, in particular. Methods We compared effects of sleep on memory consolidation between boys (9–12 years) with ASD ( n = 21) and typically developing ( TD , n = 20) boys, matched for age and IQ , in a within‐subjects crossover design. We employed an emotional picture recognition task and the Deese–Roediger–McDermott ( DRM ) word list task for assessing gist memory formation in the emotional and nonemotional domain, respectively. Learning took place before retention intervals of nocturnal sleep and daytime wakefulness, and retrieval was tested afterwards. Results Surprisingly, on the DRM task, children with ASD showed an enhanced sleep‐dependent formation of gist‐based memory (i.e. more recall of ‘critical lure words’ after sleep compared to wakefulness) than TD children, with this effect occurring on top of a diminished veridical word memory. On the picture recognition task, children with ASD also showed a stronger emotional enhancement in memory (i.e. relatively better memory for negative than neutral pictures) than TD children, with this enhancement occurring independent of sleep. Sleep polysomnography was remarkably comparable between groups. Conclusions Children with ASD show well‐preserved sleep‐dependent memory consolidation. Enhanced gist memory formation in these children might reflect a compensatory response for impairments at earlier stages of memory processing, that is during encoding.
Functional neuroplasticity in response to cerebello-thalamic injury underpins the clinical presentation of tremor in multiple sclerosis
2019-03-25

Background: Tremor is present in almost half of multiple sclerosis (MS) patients. The lack of understanding of its pathophysiology is hampering progress in development of treatments. Objectives: To clarify the structural and functional brain changes associated with the clinical phenotype of upper limb tremor in people with MS. Methods: Fifteen healthy controls (46.1 ± 15.4 years), 27 MS participants without tremor (46.7 ± 11.6 years) and 42 with tremor (46.6 ± 11.5 years) were included. Tremor was quantified using the Bain score (0–10) for overall severity, handwriting and Archimedes spiral drawing. Functional magnetic resonance imaging activations were compared between participants groups during performance of a joystick task designed to isolate tremulous movement. Inflammation and atrophy of cerebello-thalamo-cortical brain structures were quantified. Results: Tremor participants were found to have atrophy of the cerebellum and thalamus, and higher ipsilateral cerebellar lesion load compared to participants without tremor ( p &lt; 0.020). We found higher ipsilateral activation in the inferior parietal lobule, the premotor cortex and supplementary motor area in MS tremor participants compared to MS participants without tremor during the joystick task. Finally, stronger activation in those areas was associated with lower tremor severity. Conclusion: Subcortical neurodegeneration and inflammation along the cerebello-thalamo-cortical and cortical functional neuroplasticity contribute to the severity of tremor in MS.
Classical conditioning in oddball paradigm: A comparison between aversive and name conditioning
2019-03-25

Abstract The nature of cortical plasticity in learning is one of the most intriguing questions of modern cognitive neuroscience. Classical conditioning (as a typical case of associative learning) and electroencephalography together provide a good framework for expanding our knowledge about fast learning‐related cortical changes. In our experiment, we employed a novel paradigm in which classical conditioning was combined with passive oddball. Nineteen subjects participated in the first experiment (aversive conditioning with painful shock as unconditioned stimulus (US) and neutral tones as conditioned stimulus (CS)), and 22 subjects in the second experiment (with a subject’s own name as US). We used event‐related potentials (ERPs) and time‐frequency analyses to explore the CS‐US interaction. We found a learning‐induced increment of P3a in the first experiment and the late positive potential (LPP) in both experiments. These effects may be related to increased attentional and emotional significance of conditioned stimuli. We showed that the LPP and P3a effects, earlier found only in visual paradigms, generalize to the auditory sensory system. We also observed suppression of the low beta activity to CS+ in aversive conditioning over the hemisphere contralateral to expected electrical shocks, presumably indicating preparation of the somatosensory system to the expected nociceptive US.
Reactions of GeCl2 with the Thiolate LiSC(SiMe3)3: From thf Activation to Insertion of GeCl2 Molecules into C−S Bonds
2019-03-25

Abstract The reaction system GeCl 2 ⋅ dioxane/LiSTsi (Tsi=C(SiMe 3 ) 3 ) opens a fruitful area in germanium chemistry, depending on the stoichiometry and solvent used during the reaction. For example, the reaction of GeCl 2 ⋅ dioxane in toluene with two equivalents of the thiolate gives the expected germylene Ge(STsi) 2 in excellent yield. This germylene readily reacts with hydrogen and acetylene, however, in a non‐selective way. By using an excess amount of the thiolate and toluene as the solvent, the germanide [Ge(STsi) 3 ][Li(thf)] is obtained. Performing the same reaction in thf leads to a C−H activation of thf to give (H 7 C 4 O)Ge[STsi](μ 2 ‐S) 2 Ge[STsi] 2 , in which the thf molecule is still intact. Using a sub‐stoichiometric amount of the thiolate leads to the heteroleptic compound [ClGe(STsi)] 2 and to the insertion product (thf)Ge[S‐GeCl 2 ‐Tsi] 2 , in which additional GeCl 2 molecules insert into the C−S bonds of Ge(STsi) 2 . The synthesis and the experimentally determined structures of all compounds are presented together with first reactivity studies of Ge(STsi) 2 .
Time-effective strategies for the fabrication of poly- and single-crystalline gold nano-structures by focused helium ion beam milling
2019-03-25

Milling with the focused helium ion beam of a helium ion microscope is one of the most accurate ways to produce nano-structures such as plasmonic nanoantennas. In addition to good and immediate control of the dimensions, features in the sub-10 nm regime are achievable. Especially small gaps and sharp tips in this regime may lead to very high field enhancement under excitation. However, the milling rate of 30 keV helium ions is rather low, making it time-consuming to cut nano-structures out of a gold film. We present two processes to work around the low milling rate to obtain arrays of nano-structures with maximum precision within a reasonable time. These strategies can both be adapted to either poly-crystalline gold films or single-crystalline gold flakes. Using single crystals from a fabrication point of view enables even higher precision due to constant etch rates over the whole crystal as well as straight edges and vertical side-walls due to the uniform crystalline structure.
Evaluating Subsurface Parameterization to Simulate Hyporheic Exchange: The Steinlach River Test Site
2019-03-25

Abstract Hyporheic exchange is the interaction of river water and groundwater, and is difficult to predict. One of the largest contributions to predictive uncertainty for hyporheic exchange has been attributed to the representation of heterogeneous subsurface properties. Our study evaluates the trade‐offs between intrinsic (irreducible) and epistemic (reducible) model errors when choosing between homogeneous and highly complex subsurface parameter structures. We modeled the Steinlach River Test Site in Southwest Germany using a fully coupled surface water‐groundwater model to simulate hyporheic exchange and to assess the predictive errors and uncertainties of transit time distributions. A highly parameterized model was built, treated as a “virtual reality” and used as a reference. We found that if the parameter structure is too simple, it will be limited by intrinsic model errors. By increasing subsurface complexity through the addition of zones or heterogeneity, we can begin to exchange intrinsic for epistemic errors. Thus, the appropriate level of detail to represent the subsurface depends on the acceptable range of intrinsic structural errors for the given modeling objectives and the available site data. We found that a zonated model is capable of reproducing the transit time distributions of a more detailed model, but only if the geological structures are known. An interpolated heterogeneous parameter field (cf. pilot points) showed the best trade‐offs between the two errors, indicating fitness for practical applications. Parameter fields generated by multiple‐point geostatistics (MPS) produce transit time distributions with the largest uncertainties, however, these are reducible by additional hydrogeological data, particularly flux measurements.