bluuebunny/crossref_metadata_2025_split huggingface dataset:
Supramolecular Chemistry in the Biomembrane
Authors: Barba‐Bon Andrea , Nilam Mohamed , Hennig Andreas 
Published: December 2019

AbstractThe combination of supramolecular functional systems with biomolecular chemistry has been a fruitful exercise for decades, leading to a greater understanding of biomolecules and to a great variety of applications, for example, in drug delivery and sensing. Within these developments, the phospholipid bilayer membrane, surrounding live cells, with all its functions has also intrigued supramolecular chemists. Herein, recent efforts from the supramolecular chemistry community to mimic natural functions of lipid membranes, such as sensing, molecular recognition, membrane fusion, signal transduction, and gated transport, are reviewed.
S‐Adenosyl‐l‐Methionine Salvage Impacts Psilocybin Formation in “Magic” Mushrooms
Authors: Demmler Richard , Fricke Janis , Dörner Sebastian , Gressler Markus , Hoffmeister Dirk 
Published: December 2019

AbstractPsychotropic Psilocybe mushrooms biosynthesize their principal natural product psilocybin in five steps, among them a phosphotransfer and two methyltransfer reactions, which consume one equivalent of 5′‐adenosine triphosphate (ATP) and two equivalents of S‐adenosyl‐l‐methionine (SAM). This short but co‐substrate‐intensive pathway requires nucleoside cofactor salvage to maintain high psilocybin production rates. We characterized the adenosine kinase (AdoK) and S‐adenosyl‐l‐homocysteine (SAH) hydrolase (SahH) of Psilocybe cubensis. Both enzymes are directly or indirectly involved in regenerating SAM. qRT‐PCR expression analysis revealed an induced expression of the genes in the fungal primordia and carpophores. A one‐pot in vitro reaction with the N‐methyltransferase PsiM of the psilocybin pathway demonstrates a concerted action with SahH to facilitate biosynthesis by removal of accumulating SAH.
Proteome‐Wide Survey of Cysteine Oxidation by Using a Norbornene Probe
Authors: Alcock Lisa J. , Langini Maike , Stühler Kai , Remke Marc , Perkins Michael V. , Bernardes Gonçalo J. L. , Chalker Justin M. 
Published: December 2019

AbstractRapid detection of cysteine oxidation in living cells is critical in advancing our understanding of responses to reactive oxygen species (ROS) and oxidative stress. Accordingly, there is a need to develop chemical probes that facilitate proteome‐wide detection of cysteine's many oxidation states. Herein, we report the first whole‐cell proteomics analysis using a norbornene probe to detect the initial product of cysteine oxidation: cysteine sulfenic acid. The oxidised proteins identified in the HeLa cell model represent the first targets of the ROS hydrogen peroxide. The panel of protein hits provides new and important information about the targets of oxidative stress, including 148 new protein members of the sulfenome. These findings provide new leads for the study and understanding of redox signalling and diseases associated with oxidative stress.
Green Chemistry in der Schule
Authors: Linkwitz Michael , Eilks Ingo 
Published: December 2019

ZusammenfassungVom Chemieunterricht wird ein stärkerer Wandel hin zu einer Bildung für nachhaltige Entwicklung gefordert, wobei der Wandel der Chemie zu grünen und nachhaltigen Verfahrensweisen berücksichtigt werden sollte. Aber wie lässt sich die grüne Chemie theoretisch als auch praktisch in den Unterricht integrieren? Dieser Artikel gibt einen Überblick über aktuelle Entwicklungen und macht Vorschläge, wie grüne Chemie systematisch Eingang in den Chemieunterricht in der Sekundarstufe II finden kann. Er fokussiert auf die theoretischen Hintergründe und stellt ausgewählte Experimente hierzu vor.
Isolable Anion Radicals of Nitrosoarenes
Authors: Wang Dongyang , Tamizmani Masilamani , Leng Xuebing , Deng Liang 
Published: December 2019

Summary of main observation and conclusionThe rich redox chemistry of nitrosoarenes has rendered these reactive molecules very useful in modern synthetic and material chemistry. Electrochemical studies have revealed the capability of nitrosoarenes to undergo one‐electron oxidation or reduction reaction for a long time. However, the isolation and structural characterization of nitrosoarene radical compounds deviating the stabilization of transition‐metal have not been achieved. Investigation on the reduction reaction of nitrosoarenes bearing steric demanding substituents has now revealed that the interaction of 2,6‐dimesityl‐1‐nitroso‐benzene (DmpNO) or 2,4,6‐tri(tert‐butyl)‐1‐nitroso‐benzene (TtpNO) with KC8 and crypt‐2,2,2 can produce the corresponding anion radical compound [K(crypt‐2,2,2)][DmpNO] (1) or [K(crypt‐2,2,2)][TtpNO] (2) in good isolated yield. Compounds 1 and 2 represent the first examples of isolable nitrosoarene radical compounds deviating the stabilization of transition‐metal, and have been characterized by single‐crystal X‐ray diffraction study, electron paramagnetic resonance (EPR) spectroscopy, and elemental analysis. Theoretical study in collaboration with the characterization data revealed that the unpaired spin in [DmpNO]•– and [TtpNO]•– delocalizes on the nitroso and the central phenyl groups.
Forecasting Air Quality Indicators for 33 Cities in China
Authors: Wu Lifeng , Zhao Hongying 
Published: December 2019

AbstractThe Jing‐Jin‐Ji (Beijing‐Tianjin‐Hebei) and the surrounding Jin‐Lu‐Yu (Shanxi‐Shandong‐Henan) regions are experiencing severe problems with air pollution. To measure the change in pollutant concentrations over the next few years, the fractional order accumulation grey model is used to forecast the air quality indicators.
The results show that the concentrations of fine particulate matter, particulate matter 10, and sulfur dioxide show a downward trend, and 8‐h O3 (annual) and 8‐h O3 (spring and summer) show an upward trend in these areas. There is a slight increase in nitrogen dioxide concentration in Shanxi, but its concentration in other areas shows a slight decline. The results obtained can provide a clear direction for air quality management decisions.
Design, Synthesis and Discovery of N,N’‐Carbazoyl‐aryl‐urea Inhibitors of Zika NS5 Methyltransferase and Virus Replication
Authors: Spizzichino Sharon , Mattedi Giulio , Lauder Kate , Valle Coralie , Aouadi Wahiba , Canard Bruno , Decroly Etienne , Kaptein Suzanne J. F. , Neyts Johan , Graham Carl , Sule Zakary , Barlow David J. , Silvestri Romano , Castagnolo Daniele 
Published: December 2019

AbstractThe recent outbreaks of Zika virus (ZIKV) infection worldwide make the discovery of novel antivirals against flaviviruses a research priority. This work describes the identification of novel inhibitors of ZIKV through a structure‐based virtual screening approach using the ZIKV NS5‐MTase. A novel series of molecules with a carbazoyl‐aryl‐urea structure has been discovered and a library of analogues has been synthesized. The new compounds inhibit ZIKV MTase with IC50 between 23–48 μM. In addition, carbazoyl‐aryl‐ureas also proved to inhibit ZIKV replication activity at micromolar concentration.
Does interior color contrast enhance spatial memory?
Authors: Min Young Hee , Lee Soyeon 
Published: December 2019

AbstractThis study investigated the effect of contrast in neutral‐, warm‐, and cool‐colored spaces on spatial memory. Spatial memory was measured in terms of architectural scale and recollection of architectural elements and furniture. Participants (N = 114) viewed a short virtual simulation video of a residential studio and were asked to sketch a map of the architectural elements on distributed grid paper. Spatial memory was measured in terms of scale, and item recall rate. Contrast and hue had no significant effect on the memorization of proportional scale. However, high‐contrast schemes allowed for a significantly higher recollection of architectural elements than low‐contrast schemes. In comparing the effect of hues, a significant difference was seen in recalling detailed furniture and lighting items. Participants reported significantly better spatial memory of neutral and warm color schemes than of cool color schemes. There was no interaction effect between contrast and hue in the color combinations. These results can be applied in the design of color schemes for architectural spaces requiring enhanced spatial cognition and memory.
A comprehensive research on exponential smoothing methods in modeling and forecasting cellular traffic
Authors: Tran Quang Thanh , Hao Li , Trinh Quang Khai 
Published: December 2019

SummaryTraffic prediction based on time series analysis methods that are low‐cost and low computational complexity can offer more efficient resource management and better QoS. Although exponential smoothing is such a kind of method, there is a lack of application in cellular networks and data traffic research, especially with the robust development of mobile Internet applications nowadays. Therefore, this study provides a comprehensive research on cellular network traffic prediction using exponential smoothing methods. More cases of traffic including voice and data in different time granularities as well as different domains compared with other studies are considered. Besides, more exponential smoothing methods are simultaneously investigated for different cases of traffic. Our multiple case study approach leads to a more convincing result of choosing the best fit model. Data collected from real commercial cellular networks is used for experiments to make the results more practical and persuasively. In our experiment method, the model has the lowest RMSE value is chosen among three types of method. The experiment results show that exponential smoothing methods outperform multiplicative seasonal ARIMA, which is slower and more complex in computation in all cases, so they should be recommended for traffic prediction.
MFDC‐net: Multifeature‐based deep convolutional neural network for single image haze removal
Authors: Li Bin , Zhao Jingjuan , Fu Hui 
Published: December 2019

SummaryWhen it comes to the dehazing method based on the ambient light scattering model, there are ill‐conditioning problems of great concern. Therefore, the inaccurate estimation of the global atmospheric light and transmittance can bring about hue error phenomena, halo artifacts, and image noises. In this paper, we present an effective and efficient approach to solve above problems. Firstly, we adopt single‐threshold segmentation method and quad‐tree algorithms, which can break through the limitation that the dark channel prior theory (DCP) is not suitable for sky region, to quickly and accurately locate and estimate the global atmospheric light. Secondly, we design a new deep convolutional network architecture, which can effectively suppress the halo effect of image edges and restrain image noises, to optimize transmittance. Numerous of outdoor and synthesis haze image test results indicate that the optimized approach could shorten the processing time greatly. Besides, with more accurate global atmospheric light value and transmittance, the image noise and the halo artifact can be effectively suppressed and removed respectively, the hue error phenomenon improved, and the image contrast significantly enhanced in the dehazing results.
Deuteron Quadrupolar Chemical Exchange Saturation Transfer (Q‐CEST) Solid‐State NMR for Static Powder Samples: Approach and Applications to Amyloid‐β Fibrils
Authors: Vugmeyster Liliya , Ostrovsky Dmitry , Fu Riqiang 
Published: December 2019

AbstractWe provide an experimental and computational framework for 2H quadrupolar chemical exchange saturation transfer NMR experiments (Q‐CEST) under static solid‐state conditions for the quantification of dynamics on μs‐ms timescales. Simulations using simple 2‐site exchange models provide insights into the relation between spin dynamics and motions. Biological applications focus on two sites of amyloid‐β fibrils in the 3‐fold symmetric polymorph. The first site, the methyl group of A2 of the disordered N‐terminal domain, undergoes diffusive motions and conformational exchange due to transient interactions. Earlier 2H rotating frame relaxation and quadrupolar CPMG measurements are combined with the Q‐CEST approach to characterize the multiple conformational states of the domain. The second site, the methyl group of M35, spans the water‐accessible cavity inside the fibrils’ core and undergoes extensive rotameric exchange. Q‐CEST permits us to refine the rotameric exchange model for this site and allows the more precise determination of populations and rotameric exchange rate constants than line shape analysis.
Tuning the Competition between Hydrogen and Tetrel Bonds by a Magnesium Bond
Authors: Hou Mingchang , Zhu Yifan , Li Qingzhong , Scheiner Steve 
Published: December 2019

AbstractA computational study of the complexes formed by TF3OH (T=C, Si, Ge) with three nitrogen‐containing bases NCH, NH3, and imidazole (IM) is carried out at the MP2/aug‐cc‐pVTZ level. TF3OH can participate in two different types of noncovalent interactions: a hydrogen bond (HB) involving the hydroxyl proton and a tetrel bond (TB) with the tetel atom T. The strength of the HB is largely unaffected by the identity of T while the TB is enhanced as T grows larger. The HB is preferred over the TB for most systems, with the exception of GeF3OH with either NH3or IM. MgCl2engages in a Mg⋅⋅⋅O Magnesium bond (Mg‐bond) with the TF3OH O atom, which cooperatively enhances both the HB and TB. The HB strengthening is particularly large for the NH3or IM bases, and especially for CF3OH, but is slowly reduced as the T atom grows larger. The TB enhancement, on the other hand, behaves in the opposite fashion, accelerating for the larger T atoms. As a bottom line, the Mg‐bond generally reinforces and accentuates the preference for the HB or TB that is already present in the dimer. The Mg‐bond is also responsible for a proton transfer in the HB configurations with NH3and IM.
Polarization‐Dependent Photoluminescence of a Highly (100)‐Oriented Perovskite Film
Authors: Yun Sangeun , Kim Taehee , Choi Yung Ji , Lee Sang Hyeon , Kim Hae‐Jin , Kim Dongho 
Published: December 2019

AbstractLead halide perovskite is one of the attractive functional materials owing to its outstanding opto‐electronic properties, which have been addressed in numerous studies. This study aims to clarify the link between the growth pattern and the charge carrier related properties for the highly oriented perovskite film along the [100] direction. For this purpose, a CH3NH3PbI3 thin film mainly grown along the [100] direction was fabricated and subjected to spectroscopic analysis to understand the basic optoelectronic features of the oriented film. A perovskite film with random growth was also fabricated for comparison. In particular, results from excitation polarization photoluminescence spectroscopy (ExPPS) revealed that the orientation of transition dipole moment, which is relevant to the anisotropic property of the film, is attributed to the growth direction of the perovskite film. This study suggests that the absorption anisotropy can affect the anisotropy in properties of the perovskite device. Furthermore, photodetectors with the perovskite films were fabricated to investigate the effect of growth direction on the photodetector performances, revealing that a photodetector with the oriented perovskite film showed larger photoresponses. In order to provide an explanation for such result, we performed a PL lifetime imaging study of the oriented and randomly grown perovskite films.
Overexpression of JAG2 is related to poor outcomes in oral squamous cell carcinoma
Authors: Hatano Kiichi , Saigo Chiemi , Kito Yusuke , Shibata Toshiyuki , Takeuchi Tamotsu 
Published: December 2019

AbstractObjectivesJAG2 is one of Notch ligands, which recently appear to exert various carcinogenesis. In the present study, we aimed to unveil the relation of JAG2 expression and clinicopathological features in oral squamous cell carcinoma (OSCC).Materials and MethodsWe examined JAG2 expression in OSCC plus adjacent nontumorous epithelia in eight patients. Ninety‐one OSCC tissue specimens were immunohistochemically stained with specific antibodies to JAG2. The immunoreactivities of JAG2 were correlated with clinicopathological factors, including the prognosis of patients. Chi‐square test, Kaplan–Meier survival, and Cox proportional hazard analysis were used to determine the statistical value of JAG2 expression in OSCC.ResultsJAG2 mRNA expression was much expressed in OSCC tissues compared with adjacent tissue specimens in five of eight patients. JAG2 immunoreactivity was found at invasion front in 31 of 91 OSCC. JAG2 immunoreactivity was significantly associated with age, less than 50 years old of patients (P = .048). Kaplan–Meier analysis demonstrated that the patients with JAG2 immunoreactvty have a short overall survival. With the Cox proportional hazard regression mode, the independent factors predictive of poor overall survival included JAG2 immunoreactivity (P < .05).ConclusionsThe present findings suggest that JAG2 overexpression, especially at the cancer invasion front, has potential prognostic value.
Optimal spectrum utilisation in cognitive radio networks based on processor sharing techniques
Authors: Tsimba Hilary , Maharaj Bodhaswar T. , Alfa Attahiru 
Published: December 2019

SummaryCognitive radio networks have achieved higher efficiency in terms of spectrum usage; however they do not readily solve any competition for access among secondary users. Optimisation is applied to an underlay network to obtain the optimal solution for at least two secondary users operating simultaneously on the same channel. Performance measures are used as the target for optimisation. However, the objective function is difficult to obtain in closed form. For the performance measures, queueing theory, particularly weighted processor sharing techniques are employed to model the system dynamics and behaviour. Transmission power and the interference temperature limit are used to allocate weights to the secondary users. Queue length and waiting time functions obtained from the queuing models are used for optimisation. After establishing that the objective function can be considered to be pseudo‐convex, convex programming is then deployed to obtain the optimised solution. The results suggest that there is indeed an improvement in network performance after optimisation. The immediate benefits of such a system are firstly improved spectrum utilisation through adding multiple secondary users and secondly, through optimisation, higher performance that can be achieved by the secondary users.
Detailed estimation method of heat generation during charge/discharge in lithium‐ion battery using equivalent circuit
Authors: Inui Yoshitaka , Hirayama Satoshi , Tanaka Tadashi 
Published: December 2019

AbstractLithium‐ion batteries are becoming practically used for high power applications such as electric vehicles. For this purpose, some estimation technique of battery heat generation is inevitable. The authors, therefore, have already proposed a simple estimation method of the heat generation in lithium‐ion batteries during their charge/discharge using internal equivalent resistance and confirmed validity of the method for constant current discharge patterns. The merit of this method is its simplicity but it has already been made clear that its versatility for various current patterns is not enough. Considering these facts, in this study, the authors newly proposed a detailed estimation method of the heat generation in lithium‐ion batteries during their charge/discharge using equivalent circuit. The authors compared the estimation results of the heat generation in lithium‐ion battery for various constant or pulse current charge/discharge patterns through the newly proposed detailed estimation method with the estimation results through the conventional simple estimation method and measured results through a calorimeter for the corresponding current patterns. The versatility of the newly proposed detailed estimation method was successfully confirmed through these comparisons, indicating the validity and necessity of the proposed method.
Moose effects on soil temperatures, tree canopies, and understory vegetation: a path analysis
Authors: Kolstad Anders Lorentzen , Austrheim Gunnar , Graae Bente J. , Solberg Erling J. , Strimbeck G. Richard , Speed James D. M. 
Published: December 2019

AbstractLarge vertebrate herbivores are ubiquitous and increasingly numerous in boreal forests where they are known to influence ecosystems in many ways. However, separating the direct effects of herbivores from their indirect effects on plant communities via forest structural changes and microclimate remains unexplored, limiting the predictability of herbivore impacts. We used an exploratory path analysis approach to investigate potential mechanistic pathways between herbivore removal, forest canopy cover, soil temperature, and understory vegetation dynamics. Moose (Alces alces) were excluded from 15 recently clear‐cut boreal forest sites in Norway using 20 × 20 m fences with paired open un‐fenced plots. Soil temperatures and vegetation data were recorded after eight years (total n = 98). Moose exclusion reduced summer soil temperatures but not winter soil temperatures, leading to no net effect over 344 d. Path analysis showed a strong positive effect of moose exclusion on canopy cover and subsequently reduced summer soil temperatures. There was some support for an increase in the dominant grass species Avenella flexuosa with increasing summer soil temperatures, but neither temperature, canopy cover, nor A. flexuosa had clear links to plant species densities. Moose exclusion directly increased herb biomass and shifted understory species composition toward less shrub‐dominated communities, resulting in increased species densities of vascular plants and bryophytes. Our results indicate that in early‐successional boreal forests, direct effects of large herbivores on plant communities are clearly visible, and indirect effects are detectable but much weaker.