julilili42/papers huggingface dataset:
Treatment of calcified root canals in elderly people: a clinical study about the accessibility, the time needed and the outcome with a three‐year follow‐up
2016-06-14

Objective Determination of accessibility, time needed and outcome of endodontic treatment of teeth with calcified root canals in a sample of elderly participants in a private practice limited to endodontics. Background Due to demographic changes, gerodontology is becoming more and more important, also in the field of endodontology. Elderly patients can show up with severe calcifications of root canals. Root canal treatment, when needed, can be very challenging in these cases. Only few data exist about the treatment of calcified root canals and its outcome, especially in an elderly population. Materials and methods Forty‐one participants (median age: 72 years) needing a root canal treatment were included. The total number of treated teeth was 41 with 114 negotiated root canals. A specialist limited to endodontics performed the treatment in a private practice. Outcome was assessed by applying the periapical index score on the basis of recall radiographs provided by the referring dentists. Likewise, time required to localise the root canals was measured. Results All root canals have been detected using the operating microscope, and full working length could be established in 90% of the cases. Success rate was 80% after an observation time of 3 years. In three of five teeth, root canals could be localised within 15 min. Conclusion Calcified root canals of older people treated in this study were all accessible within a maximum of 60 min. The success rate after a follow‐up of 3 years was 80%.
A Southern Hemisphere record of global trace‐metal drawdown and orbital modulation of organic‐matter burial across the Cenomanian–Turonian boundary (Ocean Drilling Program Site 1138, Kerguelen Plateau)
2016-06-14

Abstract Despite its assumed global nature, there are very few detailed stratigraphic records of the late Cenomanian to the early Turonian Oceanic Anoxic Event 2 from the Southern Hemisphere. A highly resolved record of environmental changes across the Cenomanian–Turonian boundary interval is presented from Ocean Drilling Program Site 1138 on the central Kerguelen Plateau (southern Indian Ocean). The new data lead to three key observations. Firstly, detailed biostratigraphy and chemostratigraphy indicate that the record of Oceanic Anoxic Event 2 is not complete, with a hiatus spanning the onset of the event. A decrease in glauconite and highly weathered clays after the onset of Oceanic Anoxic Event 2 marks the end of the hiatus interval, which can be explained by a relative sea‐level rise that increased sediment accommodation space on the Kerguelen Plateau margin. This change in depositional environment controlled the timing of the delayed peak in organic‐matter burial during Oceanic Anoxic Event 2 at Site 1138 compared with other Oceanic Anoxic Event 2 locations worldwide. A second key observation is the presence of cyclic fluctuations in the quantity and composition of organic matter being buried on the central Kerguelen Plateau throughout the latter stages of Oceanic Anoxic Event 2 and the early Turonian. A close correspondence between organic matter, sedimentary elemental compositions and sediments recording sea‐floor oxygenation suggests that the cycles were mainly productivity‐driven phenomena. Available age‐control points constrain the periodicity of the coupled changes in sedimentary parameters to ca 20 to 70 ka, suggesting a link between carbon burial and astronomically forced climatic variations (precession or obliquity) in the Southern Hemisphere mid‐latitudes both during, and after, Oceanic Anoxic Event 2: fluctuations that were superimposed on the impact of global‐scale processes. Finally, trace‐metal data from the black‐shale unit at Site 1138 provide the first evidence from outside of the proto‐North Atlantic region for a global drawdown of seawater trace‐metal (Mo) inventories during Oceanic Anoxic Event 2.
Drell-Yan lepton angular distributions in perturbative QCD
2016-06-14

We present a comprehensive comparison of the available experimental data for\\nthe Drell-Yan lepton angular coefficients and to calculations\\nat leading and next-to-leading order of perturbative QCD. To obtain the\\nnext-to-leading order corrections, we make use of publicly available numerical\\ncodes that allow us to compute the Drell-Yan cross section at second order in\\nperturbation theory and from which the contributions we need can be extracted.\\nOur comparisons reveal that perturbative QCD is able to describe the\\nexperimental data overall rather well, especially at colliders, but also in the\\nfixed-target regime. On the basis of the angular coefficients alone, there\\nappears to be little (if any) convincing evidence for effects that go beyond\\nfixed-order collinear factorized perturbation theory, although the presence of\\nsuch effects is not ruled out.\\n
Synthesis and antibacterial activity of N1-(carbazol-3-yl)amidrazones incorporating piperazines and related congeners
2016-06-14

Abstract A selected set of N 1-(4-chloro-9-ethylcarbazol-3-yl)amidrazones ( 7a–n ) has been synthesized by reacting the respective hydrazonoyl chloride 5 derived from 3-amino-9-ethylcarbazole ( 3 ), with an appropriate sec -cyclic amine ( 6a–n ) in ethanol in the presence of triethylamine. Unexpectedly, aromatic ring chlorination occurred at C-4 of 3 during its conversion to 6 as evidenced by analytical and spectral data and further confirmed by single crystal X-ray structure determination of the amidrazone 7n . Compounds 7a–n were tested for their in vitro antibacterial activity. Among the tested bacterial strains, methicillin-resistant Staphylococcus aureus was the most susceptible to 7f and Bacillus cereus to 7b both with a minimum inhibitory concentration value of 1.56 μg mL −1 . Compounds 7c , 7f , and 7h could be useful as lead structures for further development of new antibacterial agents against Gram-positive and Gram-negative pathogens.
Molecular neuropathology of frontotemporal dementia: insights into disease mechanisms from postmortem studies
2016-06-15

Abstract Frontotemporal dementia ( FTD ) is a clinical syndrome with a heterogeneous molecular basis. The past decade has seen the discovery of several new FTD ‐causing genetic mutations and the identification of many of the relevant pathological proteins. The current neuropathological classification is based on the predominant protein abnormality and allows most cases of FTD to be placed into one of three broad molecular subgroups; frontotemporal lobar degeneration with tau, TDP ‐43 or FET protein accumulation. This review will describe our current understanding of the molecular basis of FTD , focusing on insights gained from the study of human postmortem tissue, as well as some of the current controversies. image Most cases of FTD can be subclassified into one of three broad molecular subgroups based on the predominant protein that accumulates as pathological cellular inclusions. Understanding the associated pathogenic mechanisms and recognizing these FTD molecular subtypes in vivo will likely be crucial for the development and use of targeted therapies. This article is part of the Frontotemporal Dementia special issue .
Incorporating limited field operability and legacy soil samples in a hypercube sampling design for digital soil mapping
2016-06-15

Abstract Most calibration sampling designs for Digital Soil Mapping (DSM) demarcate spatially distinct sample sites. In practical applications major challenges are often limited field accessibility and the question on how to integrate legacy soil samples to cope with usually scarce resources for field sampling and laboratory analysis. The study focuses on the development and application of an efficiency improved DSM sampling design that (1) applies an optimized sample set size, (2) compensates for limited field accessibility, and (3) enables the integration of legacy soil samples. The proposed sampling design represents a modification of conditioned Latin Hypercube Sampling (cLHS), which originally returns distinct sample sites to optimally cover a soil related covariate space and to preserve the correlation of the covariates in the sample set. The sample set size was determined by comparing multiple sample set sizes of original cLHS sets according to their representation of the covariate space. Limited field accessibility and the integration of legacy samples were incorporated by providing alternative sample sites to replace the original cLHS sites. We applied the modified cLHS design (cLHS adapt ) in a small catchment (4.2 km 2 ) in Central China to model topsoil sand fractions using Random Forest regression (RF). For evaluating the proposed approach, we compared cLHS adapt with the original cLHS design (cLHS orig ). With an optimized sample set size n = 30, the results show a similar representation of the cLHS covariate space between cLHS adapt and cLHS orig , while the correlation between the covariates is preserved ( r = 0.40 vs. r = 0.39). Furthermore, we doubled the sample set size of cLHS adapt by adding available legacy samples (cLHS adapt+ ) and compared the prediction accuracies. Based on an external validation set cLHS val ( n = 20), the coefficient of determination ( R 2 ) of the cLHS adapt predictions range between 0.59 and 0.71 for topsoil sand fractions. The R 2 ‐values of the RF predictions based on cLHS adapt+ , using additional legacy samples, are marginally increased on average by 5%.
Vδ2+ and α/β T cells show divergent trajectories during human aging
2016-06-15

Chronological aging and a variety of stressors are driving forces towards immunosenescence. While much attention was paid to the main T cell component, α/β T cells, few studies concentrate on the impact of age on γ/δ T cells' characteristics. The latter are important players of adaptive immunity but also have features associated with innate immunity. Vδ2+ are the main component of γ/δ while Vδ1+ T cells expand upon Cytomegalovirus (CMV) infection and with age. The Vδ2+ T cells are not influenced by persistent infections but do contribute to immunosurveillance against bacterial pathogens. Here, we focus on Vδ2+ T cells and report that their composition and functionality is not altered in older adults. We have performed a side-by-side comparison of α/β and Vδ2 cells by using two robust markers of T cell replicative history and cell differentiation (CD28 and CD27), and cytokine secretion (IFN-γ and TNF-α). Significant differences in Vδ2 versus α/β homeostasis, as well as phenotypic and functional changes emerged. However, the data strongly suggest a sustained functionality of the Vδ2 population with age, independently of the challenge. This suggests differential trajectories towards immunosenescence in α/β and Vδ2+ T cells, most likely explained by their intrinsic functions.
Ring Enlargement of Three‐Membered Boron Heterocycles upon Reaction with Organic π Systems: Implications for the Trapping of Borylenes
2016-06-15

Abstract New low‐energy pathways for the reaction between substituted boriranes and borirenes with unsaturated hydrocarbons (ethyne or ethene) were discovered using density functional and coupled cluster theory. The interaction between the π bond of the hydrocarbon and the empty p orbital of the boron center leads to ring expansion of the three‐membered to a five‐membered boron heterocycle. The reactions are strongly exothermic and have low or even no barriers. They involve intermediates with a pentacoordinate boron center with two hydrocarbon molecules coordinating to boron akin to metal‐olefin complexes. These borylene complexes are shallow minima on the potential energy surfaces. But significantly higher barriers for ring formation are computed for 1,5‐cyclooctadiene and dibenzocyclooctatetraene complexes of borylenes, making these complexes likely detectable under appropriate experimental conditions. Our computational findings have implications for the interpretation of trapping experiments of thermally generated small borylenes with excess of small π systems. Because of very low barriers for reactions of three‐membered boron heterocycles with π systems and the at least locally large excess of the latter under such conditions, formation of five‐membered boron heterocycles should be considered.
Nanobody Platform for Determination of Protein Structure, Application of
2016-06-15

Abstract Since their first description 20 years ago, single‐domain antibody fragments derived from heavy‐chain‐only antibodies of camelids, the so‐called nanobodies, have emerged as reliable recombinant binding molecules for the proteomic research community. The facile identification of antigen‐specific nanobodies and their beneficial biochemical properties regarding size, affinity, and stability supported by multiple crystal structures turn those proteins into versatile binders suitable for multiple applications in the field. During the past decade, nanobodies have been shown as highly functional chaperones assisting the crystallization process of challenging proteins and large protein complexes. In this article, we provide the background knowledge about nanobodies and review their recent application as crystallization chaperones for the determination of protein structures.
PI3K Pathway Inhibition Achieves Potent Antitumor Activity in Melanoma Brain MetastasesIn VitroandIn Vivo
2016-06-16

Abstract Purpose: Great advances have recently been made in treating patients with metastatic melanoma. However, existing therapies are less effective on cerebral than extracerebral metastases. This highlights the potential role of the brain environment on tumor progression and drug resistance and underlines the need for “brain-specific” therapies. We previously showed that the PI3K-AKT survival pathway is hyperactivated in brain but not extracerebral melanoma metastases and that astrocyte-conditioned medium activates AKT in melanoma cells in vitro. We therefore tested the PI3K inhibitor buparlisib as an antitumor agent for melanoma brain metastases. Experimental Design and Results: Buparlisib inhibited AKT activity, decreased proliferation, and induced apoptosis in metastatic melanoma cell lines and short-term brain melanoma cells, irrespective of their BRAF and NRAS mutation status. In addition, buparlisib inhibited hyperactivated AKT and induced apoptosis in melanoma cells that were stimulated with astrocyte-conditioned medium. The growth of tumors induced by injecting human BRAF- and NRAS-mutant metastatic melanoma cells into the brain of mice was significantly inhibited by buparlisib. Conclusions: These results emphasize the value of targeting the PI3K pathway as a strategy to develop drugs for melanoma brain metastases. Clin Cancer Res; 22(23); 5818–28. ©2016 AACR.
Efficacy and safety of a single occipital nerve blockade in episodic and chronic cluster headache: A prospective observational study
2016-06-16

Background Treatment options for cluster headache (CH) include acute, transitional and prophylactic strategies. We assessed the efficacy and safety of a single occipital nerve block (ONB) in patients with episodic (eCH) and chronic CH (cCH). Methods In this prospective, observational study 101 CH were treated with a single ONB using triamcinolone 10 mg and bupivacaine. Attack frequency, pain intensity and side effects were assessed at days 1 and 7 after ONB and thereafter weekly for 60 days until recurrence of attacks. Results Baseline mean daily attack frequency was 2.9 ± 2.5 (eCH) and 3.3 ± 2.9 (cCH), which was reduced to 0.7 ± 1.2 (eCH) and 1.1 ± 1.4 (cCH) after one day ( p = 0.08 for group difference) and to 1.1 ± 1.6 (eCH) and 1.9 ± 2.3 (cCH) after seven days ( p = 0.01 for group difference). In patients with eCH the pain-free period lasted longer compared to cCH ( p = 0.004). There was no association between the presence of local anesthesia and treatment response ( p = 0.88). No serious adverse events occurred. Conclusion ONB is an easy, safe and effective transitional treatment option in case of insufficient response of CH to treatment both in patients with eCH and cCH. Patients with eCH have a better and more sustainable treatment response.
A young supernova remnant illuminating nearby molecular clouds with cosmic rays
2016-06-16

\\n The supernova remnant (SNR) HESS J1731-347 displays strong nonthermal TeV γ-ray and X-ray emission, thus the object is presently accelerating particles to very high energies. A distinctive feature of this young SNR is the nearby (~30 pc in projection) extended source HESS J1729-345, which is currently unidentified but is in spatial projection coinciding with known molecular clouds (MC). We model the SNR evolution to explore whether the TeV emission from HESS J1729-345 can be explained as emission from runaway hadronic cosmic rays (CRs) that are illuminating these MCs. The observational data of HESS J1729-345 and HESS J1731-347 can be reproduced using core-collapse SN models for HESS J1731-347. Starting with different progenitor stars and their presupernova environment, we model potential SNR evolution histories along with the CR acceleration in the SNR and the diffusion of the CRs. A simplified three-dimensional structure of the MCs is introduced based on 12CO data of that region, adopting a distance of 3.2 kpc to the source. A Monte Carlo based diffusion model for the escaping CRs is developed to deal with the inhomogeneous environment. The fast SNR forward shock speed, as implied from the X-ray data, can easily be explained when employing scenarios with progenitor star masses between 20 M⊙ and 25 M⊙, where the SNR shock is still expanding inside the main-sequence (MS) bubble at present time. The TeV spectrum of HESS J1729-345 is satisfactorily fitted by the emission from the highest energy CRs that have escaped the SNR, using a standard Galactic CR diffusion coefficient in the interclump medium. The TeV image of HESS J1729-345 can be explained with a reasonable three-dimensional structure of MCs. The TeV emission from the SNR itself is dominated by leptonic emission in this model. We also explore scenarios where the shock is starting to encounter the dense MS progenitor wind bubble shell. The escaping hadronic CR hypothesis for the γ-ray emission of HESS J1729-345 can still hold,but even in this case our model cannot easily account for the TeV emission from HESS J1731-347 in a hadronic scenario. \\n
Testing the Kerr nature of black hole candidates using iron line reverberation mapping in the Cardoso-Pani-Rico framework
2016-06-16

The iron K line commonly observed in the X-ray spectrum of black hole\\ncandidates is produced by X-ray fluorescence of the inner accretion disk. This\\nline can potentially be quite a powerful tool to probe the spacetime geometry\\naround these objects and test the Kerr black hole hypothesis. In a previous\\npaper, we studied the ability to constrain possible deviations from the Kerr\\nsolution from the standard time-integrated iron line spectrum within the\\nCardoso-Pani-Rico framework. In the present work, we expand on that study and\\nconsider iron line reverberation mapping in the CPR framework. That is, we\\nconsider the time-evolution of the iron line profile in response to\\nfluctuations in the X-ray primary source. Our simulations clearly show that the\\ntime information in reverberation mapping can better constrain the background\\nmetric than the time-integrated approach, and this is true, notably, for the\\ndeformation parameter , which is only weakly informed by a\\ntime-integrated observation.\\n
Exercise Experiences and Changes in Affective Attitude: Direct and Indirect Effects of In Situ Measurements of Experiences
2016-06-16

At the between-person level, a direct effect on changes in affective attitude was found for perceptions of competence (β = 0.24, p < 0.05). The model revealed one significant indirect pathway between perceived exertion and changes in affective attitude via positive activation: on average, the less strenuous people perceive physical exercise to be, the more awake they will feel during exercise (β = -0.57, p < 0.05). Those people with higher average levels of positive activation during exercise exhibit more improvements in affective attitudes toward exercise from the beginning to the end of the 13-weeks exercise program (β = 0.24, p < 0.05). Main study results have revealed that in situ experiences predicted changes in affective attitude during multi-week exercise programs. These relevant in situ experiences encompass cognitive factors, the sensation of interoceptive cues, and affective responses to exercise. Considering the predictive role of affective attitudes for exercise behavior, these findings suggest that exercise interventions should put greater emphasis on specific exercise experiences.
Controlling the Emotional Bias: Performance, Late Positive Potentials, and the Effect of Anodal Transcranial Direct Current Stimulation (tDCS)
2016-06-16

Cognitive control of emotional processing is essential for adaptive human behavior. Biased attention toward emotionally salient information is critically linked with affective disorders and is discussed as a promising treatment target. Anodal (activity enhancing) transcranial direct current stimulation (tDCS) has been shown to increase healthy and impaired cognitive control over emotional distraction and is therefore widely used for the investigation and experimental treatment of this disorder. In this study, event-related potential (ERP) were recorded parallel to tDCS to track its online effects. Healthy volunteers (n = 87) performed a delayed working memory paradigm with emotional salient and neutral distractors during stimulation with different intensities (sham, 0.5, 1, 1.5 mA). Measuring the late positive potential (LPP), an ERP that indexes attention allocation, we found that a valence-specific increase of the early portion of the LPP (eLPP, 250-500 ms) was associated with less emotional distraction in the sham group. Of note, stimulation with tDCS exerted an intensity related effect on this correlation. The later part of the LPP (lLPP, 500-1000 ms) was found to be correlated with reaction time, regardless of valence. General effect of tDCS on LPPs and task performance were not observed. These findings demonstrate that ERP recordings parallel to tDCS are feasible to investigate the neuronal underpinnings of stimulation effects on executive functions. Furthermore, they support the notion that the LPP induced by a distractive stimulus during a working memory task mirrors the additional allocation of neuronal resources with a specific sensitivity of the early LPP for highly arousing negative stimuli. Finally, together with the variable magnitude and direction of the emotional bias, the lack of systematic modulations of LPPs and behavior by tDCS further underlines the important influence of the individual brain activity patterns on stimulation effects both on the behavioral and neurophysiological level.