bluuebunny/crossref_metadata_2025 huggingface dataset:
Direct C–H functionalization of difluoroboron dipyrromethenes (BODIPYs) at β-position by iodonium salts
Authors: Ren Wenming , Xiang Huaijiang , Peng Chengyuan , Musha Zulipali , Chen Jingjing , Li Xin , Huang Ruimin , Hu Youhong
Published: February 2018

A copper-catalyzed direct C–H arylation or vinylation of BODIPYs at the β-position by iodonium salts has been developed and β-styryl BODIPY 9b has great potential for photodynamic therapy.
The formation of (NiFe)S2 pyrite mesocrystals as efficient pre-catalysts for water oxidation
Authors: Ni Bing , He Ting , Wang Jia-ou , Zhang Simin , Ouyang Chen , Long Yong , Zhuang Jing , Wang Xun
Published: February 2018

We have fabricated (NiFe)S2 pyrite mesocrystals in the form of nearly-single crystalline porous cubes that self-optimize for efficient catalysis of water oxidation under electrochemical conditions.
Role of oversized dopant potassium on the nanostructure and thermoelectric performance of calcium cobaltite ceramics
Authors: Romo-De-La-Cruz C. , Liang L. , Navia S. A. Paredes , Chen Y. , Prucz J. , Song X.
Published: February 2018

The impact of the non-stoichiometric addition of potassium (K) on the nanostructure and thermoelectric performance of misfit layered calcium cobaltite (Ca3Co4O9) ceramics is reported.
Observing different dynamic behaviors of weakly and strongly adsorbed polystyrene chains at interfaces
Authors: Li Xu , Han Xiaofeng , Wang Xiaoliang , Chen Zhan , Lu Xiaolin
Published: February 2018

Understanding the dynamic behavior of polymer chains adsorbed onto a solid surface is of great importance for elucidating polymer–surface interactions.
Low-temperature processed non-TiO2 electron selective layers for perovskite solar cells
Authors: Guo Zhanglin , Gao Liguo , Zhang Chu , Xu Zhenhua , Ma Tingli
Published: February 2018

We systematically summarized the current progress in low-temperature processed non-TiO2 electron selective layers for perovskite solar cells.
Construction of orderly hierarchical FeOOH/NiFe layered double hydroxides supported on cobaltous carbonate hydroxide nanowire arrays for a highly efficient oxygen evolution reaction
Authors: Chi Jun , Yu Hongmei , Jiang Guang , Jia Jia , Qin Bowen , Yi Baolian , Shao Zhigang
Published: February 2018

An orderly hierarchical OER electrode used in an APEWE shows great performance.
The effect of segregation structure on the colossal permittivity properties of (La0.5Nb0.5)xTi1−xO2 ceramics
Authors: Li Lingxia , Lu Te , Zhang Ning , Li Jiangteng , Cai Zhaoyang
Published: February 2018

The activation energies of the grain-boundary and different polarizations are researched to reveal the effect of the segregation structure on the performance.
Collaboration and competition: ethics in toxicology
Authors: Walker Emma S. , Roberts Ruth A.
Published: February 2018

From animal research through adverse events in clinical trials to health scares around food contamination, toxicology has frequently been a focus of scientific and societal concern. As these concerns shift with each new drug, new technology or public health scare, how can toxicology stay current, relevant and ethical? Two of the biggest ethical challenges in pharmaceutical toxicology are the use of animals in testing and the high safety-related attrition rates in new drug development. Both of these require progress in the discipline that will only be driven by research funding. Yet, very little is invested in these two fields compared with investment in new efficacy models, new disease targets and new technologies. How can this be addressed? Here, we explore current paradigms in toxicology that may have the potential for perceived or actual unethical ramifications. We discuss the underpinnings of such practices and make recommendations for change around peer review, resourcing, transparency and data sharing. These ideas build on the analysis presented in the 2004 Paton Prize lecture (Purchase, 2004) where issues around conflict of interest (COI), collaboration and competition in the context of ethical behaviours were highlighted. These areas are clearly relevant to many aspects of scientific research but here we focus on toxicology and specifically toxicology in the pharmaceutical industry.
Effect of support composition on the structural and catalytic properties of Ru/AlOOH–SiO2catalysts for benzene selective hydrogenation
Authors: Zhou Gongbing , Dong Yanlu , Jiang Lan , He Daiping , Yang Ya , Zhou Xin
Published: February 2018

A volcano-type correlation between the acid amount and cyclohexene selectivity over the Ru/AlOOH–SiO2catalysts was elucidated in benzene selective hydrogenation.
Rh(iii)-Catalyzed directed C–H carbenoid coupling reveals aromatic bisphosphonates inhibiting metallo- and Serine-β-lactamases
Authors: Zhang Chen , Pu Yan-chi , Yu Zhu-Jun , Wu Cheng-yong , Brem Jürgen , McDonough Michael A. , Schofield Christopher J. , Li Guo-Bo , Wu Yong
Published: February 2018

The C–H coupling of arenes with diazo-methylene-diphosphonates enables efficient synthesis of new diphosphonates, which exhibit dual MBL and SBL inhibition.
A Meta-Analysis: Acoustic Measurement of Roughness and Breathiness
Authors: v. Latoszek Ben Barsties , Maryn Youri , Gerrits Ellen , De Bodt Marc
Published: February 2018

Purpose

Over the last 5 decades, many acoustic measures have been created to measure roughness and breathiness. The aim of this study is to present a meta-analysis of correlation coefficients (
r
) between auditory-perceptual judgment of roughness and breathiness and various acoustic measures in both sustained vowels and continuous speech.

Method

Scientific literature reporting perceptual–acoustic correlations on roughness and breathiness were sought in 28 databases. Weighted average correlation coefficients (
r
w
) were calculated when multiple
r
-values were available for a specific acoustic marker. An
r
w
≥ .60 was the threshold for an acoustic measure to be considered acceptable.

Results

From 103 studies of roughness and 107 studies of breathiness that were investigated, only 33 studies and 34 studies, respectively, met the inclusion criteria of the meta-analysis on sustained vowels. Eighty-six acoustic measures were identified for roughness and 85 acoustic measures for breathiness on sustained vowels, in which 43 and 39 measures, respectively, yielded multiple
r
-values. Finally, only 14 measures for roughness and 12 measures for breathiness produced
r
w
≥ .60. On continuous speech, 4 measures for roughness and 21 measures for breathiness were identified, yielding 3 and 6 measures, respectively, with multiple
r
-values in which only 1 and 2, respectively, had
r
w
≥ .60.

Conclusion

This meta-analysis showed that only a few acoustic parameters were determined as the best estimators for roughness and breathiness.
Low‐power‐delay‐product radix‐4 8*8 Booth multiplier in CMOS
Authors: Xue H. , Patel R. , Boppana N.V.V.K. , Ren S.
Published: February 2018

The quest continues for microelectronic implementations with higher throughput and reduced power consumption, particularly for digital signal processing, graphic processing unit and CPU portable applications. This Letter focuses on the digital multiplier circuit, which is a key component in determining the power‐delay‐product for numerous battery powered applications. A proposed radix‐4 8 × 8 Booth multiplier is implemented using four stages with a unique optimised stage‐1 architecture. Instead of using adder/subtractor in stage‐1, it is replaced with a novel binary‐to‐2's complement converter and a 2:1 MUX to reduce the delay and power consumption by 7.08 and 49.46%, respectively, compared to the other stages. The proposed design is implemented using CMOS 90 nm technology with 1.2 V supply to demonstrate performance.
Near‐field wideband source localisation from the sparse recovery perspective via the spatial‐only modelling of array data
Authors: Yan Xuezhi , Wen Yanxin , Liu Guohong
Published: February 2018

This study presents an efficient algorithm for near‐field wideband source localisation. By exploring the characters of spatial‐only modelling for near‐field wideband array output, the authors firstly construct a virtual array output in which the virtual direction matrix is free of frequency and only related to bearing and range. Then, they exploit the symmetrical property of a uniform linear array to build a special measurement vector merely corresponding to the bearing, and obtain the related estimates via ‐norm optimisation solution. By substituting the estimated bearings and vectoring the spatial covariance matrix, they obtain range estimates through a similar sparse signal reconstruction approach without a parameter pairing process. Compared with previous methods, the proposed algorithm avoids performance degradation caused by frequency decomposition and provides improved resolution and preferable robustness to noise. Numerical simulations are conducted to demonstrate the efficiency of the proposed algorithm.
Analysis and power evaluation of window‐stopped parallel turbo decoding for LTE rate matching
Authors: Lin Cheng‐Hung , Guo Shu‐Wei , Ou Li‐An
Published: February 2018

Long‐term evolution (LTE) adopts rate matching (RM) to reach high‐speed data transmission. According to the LTE hybrid automatic repeat request scheme, the receiver can correct multiple transmission data with distinct code rates. Here, the window‐stopped (WS) criterion is reinvestigated for the single‐binary (SB) turbo code in LTE RM. The parallel SB WS turbo decoding for LTE RM with distinct parameters is analysed in terms of window stopping rate, kernel stopping rate, and correcting performance. Experimental results reveal that the early termination technique does not work well for high‐code‐rate decoding. However, the SB WS criterion significantly achieves up to 19% window stopping for decoding large codeword blocks and 37% kernel stopping for decoding small codeword blocks. Moreover, the SB WS criterion is implemented within a parallel turbo decoder for LTE RM using a 90 nm CMOS process. The evaluation results show that the power dissipation of the implemented WS parallel turbo decoder can be significantly reduced by 17% with a 0.7% area overhead for high‐code‐rate decoding and high channel quality.
Thermal aging test for transformer oil–paper insulation under over‐load condition temperature
Authors: Yang Li Jun , Sun Weidong , Gao Sihang , Hao Jian
Published: February 2018

The accelerated thermal aging test is an effective method to simulate insulation material degradation in oil‐immersed transformers. Traditionally, cellulose paper and mineral oil are heated up together at the same temperature when a thermal aging test is conducted. However, variation occurs between laboratory results and field conditions. Temperature gradients exist in real transformers, and each part of the winding is aged under various conditions. In order to rebuild temperature gradients and conduct a thermal aging test under this condition. First, 3D models with designed U‐shape wingding which can guarantee different parts aged simultaneously under different temperatures are calculated for temperature field analysis. Then a thermal aging platform with a large current generator is proposed to construct temperature gradients in a thermal aging test. The large current generator helps to heat up the copper winding. Temperature sensors are installed in the aging tank to monitoring winding and oil temperature and control temperature. The aging temperature is selected according to the standard IEC 60076‐7 for the over‐load condition. The degree of polymerisation of the insulation paper is measured and properties of each layer of the insulation paper are analysed. Other aging products under both traditional test and method in this study are compared.
Wavelet‐based short‐term forecasting with improved threshold recognition for urban expressway traffic conditions
Authors: Xiangxue Wang , Lunhui Xu
Published: February 2018

Accurate traffic flow prediction can provide reliable and precise information for traffic departments to formulate effective management measures and assist drivers in performing more intelligent route planning and rerouting. The authors propose a short‐term traffic flow forecasting framework for urban expressways based on data‐driven mixed models including an approach to traffic flow threshold identification based on an improved semi‐supervised K ‐means clustering algorithm, a hybrid multi‐scale traffic speed forecasting method based on wavelet decomposition, and a traffic condition index corresponding to three‐phase traffic flow theory for reflecting traffic status in real time. Model performance evaluation is performed using multi‐source travel speed data. The results show that the traffic threshold recognition algorithm can correctly identify traffic speed thresholds confirming to the three‐phase traffic flow transition and that the proposed short‐term estimation technique outperforms traditional auto‐regressive integrated moving average models, extended Kalman filtering methods, and artificial neural network models in terms of both accuracy and robustness. The proposed traffic condition index using adaptive thresholds and predicted speeds can provide real‐time quantitative surveillance for urban expressway traffic.
Deep learning‐based real‐time fine‐grained pedestrian recognition using stream processing
Authors: Zhang Weishan , Wang Zhichao , Liu Xin , Sun Haoyun , Zhou Jiehan , Liu Yan , Gong Wenjuan
Published: February 2018

Real‐time recognition of pedestrian details can be very important in emergency situations for security reasons, such as traffic accidents identification from traffic video. However, this is challenging due to the needed accuracy of video data mining, and also the performance for real‐time video processing. Here, the authors propose a solution for fine‐grained pedestrian recognition in monitoring scenarios using deep learning and stream processing cloud computing, which is called DRPRS (deep learning‐based real‐time fine‐grained pedestrian recognition using stream processing). The authors design an improved convolutional neural network (CNN) network called fine‐CNN, which is a nine‐layer neural network for detailed pedestrian recognition. In DRPRS, a pedestrian in a surveillance video is segmented and fine‐grainedly recognised using improved single‐shot detector and several fine‐CNNs. DRPRS is supported by parallel mechanisms provided by Apache Storm stream processing framework. In addition, in order to further improve the recognition performance, a GPU‐based scheduling algorithm is proposed to make full use of GPU resources in a cluster. The whole recognition process is deployed on a big video data processing platform to meet real‐time requirements. DRPRS is extensively evaluated in terms of accuracy, fault tolerance, and performance, which show that the proposed approach is efficient.
Design and analysis of a novel coupled inductor structure with variable coupling coefficient
Authors: Pajnić Milan , Pejović Predrag , Aleksić Obrad
Published: February 2018

This study presents a new coupled inductor magnetic structure with variable coupling coefficient. The new symmetrical magnetic structure is composed of stacked ferrite cores, where control legs are placed in the centre of the core structure, on equal distances from the outer legs. In that way, the coupling coefficient is controlled by the means of a DC current. The DC control flux is confined only to the control legs and it is equally balanced in both of the outer legs. Distribution of the control DC flux in the proposed structure is verified applying finite element analysis simulation of the three‐dimensional model. Electrical properties of the new variable coupled inductor are derived applying analytical modelling and verified by experiments. Maximal variations of the controlled coupling coefficient value in respect to the different value of the leakage flux are obtained and presented. Design and experimental results are presented for application in an interleaved boost converter with a variable coupled inductor, achieving boundary conduction mode over a wide load variation.
Stokes based sigma filter for despeckling of compact PolSAR data
Authors: Sharma Rakesh , Panigrahi Rajib Kumar
Published: February 2018

In this study, a speckle filtering technique is proposed for coherent compact polarimetric synthetic aperture radar (PolSAR) data based on the statistics of Stokes parameters. The data processing and analysis of coherent compact PolSAR configurations usually start with Stokes vector representation of the data. In this study, the Stokes parameter statistics is discussed and validated, and a modified form of the state‐of‐the‐art Lee sigma filter for compact PolSAR data is presented. Also, a novel algorithm for evaluation of sigma ranges as a function of the degree of polarisation and mean intensities is proposed. An approach based on the statistics of Stokes parameter for the distinction of homogeneous and heterogeneous areas is also presented in this study. The proposed technique is effective in speckle reduction, preservation of fine details, strong targets and scattering information. The decomposition with the proposed filter as a pre‐processing step improves the land cover classification accuracy. The computational efficiency of the proposed filter is comparable to Lee sigma filter and hence the proposed filter is equally suitable for voluminous high resolution datasets. The results obtained from the developed speckle filter are validated for hybrid‐PolSAR RISAT‐1 data, hybrid‐PolSAR data synthesised from RADARSAT‐2 data and simulated PolSAR data by Monte Carlo simulation.
Review of the systems biology of the immune system using agent‐based models
Authors: Shinde Snehal B. , Kurhekar Manish P.
Published: February 2018

The immune system is an inherent protection system in vertebrate animals including human beings that exhibit properties such as self‐organisation, self‐adaptation, learning, and recognition. It interacts with the other allied systems such as the gut and lymph nodes. There is a need for immune system modelling to know about its complex internal mechanism, to understand how it maintains the homoeostasis, and how it interacts with the other systems. There are two types of modelling techniques used for the simulation of features of the immune system: equation‐based modelling (EBM) and agent‐based modelling. Owing to certain shortcomings of the EBM, agent‐based modelling techniques are being widely used. This technique provides various predictions for disease causes and treatments; it also helps in hypothesis verification. This study presents a review of agent‐based modelling of the immune system and its interactions with the gut and lymph nodes. The authors also review the modelling of immune system interactions during tuberculosis and cancer. In addition, they also outline the future research directions for the immune system simulation through agent‐based techniques such as the effects of stress on the immune system, evolution of the immune system, and identification of the parameters for a healthy immune system.
Carbonised composite materials based on elastomers filled with carbon nanofillers
Authors: Stepashkin Andrey A. , Chukov Dilyus I. , Kaloshkin Sergey D. , Pyatov Ivan S. , Deniev Magomed Ya.
Published: February 2018

New carbon–carbon composite materials with operating temperatures up to 400°C obtained by carbonisation of highly filled elastomeric compounds filled with carbon fillers of various morphologies are proposed. Low‐temperature carbonisation in a range of 300–400°C allowed to produce thermally and dimensionally stable composite materials from elastomeric compounds. The carbonised composites show rather high values of tensile, compressive and flexural strength, as well as relatively high impact toughness.
New insights into the outflows from R Aquarii
Authors: Liimets T. , Corradi R. L. M. , Jones D. , Verro K. , Santander-García M. , Kolka I. , Sidonio M. , Kankare E. , Kankare J. , Pursimo T. , Wilson P. A.
Published: February 2018

Context. The source R Aquarii is a symbiotic binary surrounded by a large and complex nebula with a prominent curved jet. It is one of the closest known symbiotic systems, and therefore offers a unique opportunity to study the central regions of these systems and the formation and evolution of astrophysical jets.

Aims. We aim to study the evolution of the central jet and outer nebula of R Aqr, taking advantage of a long term monitoring campaign of optical imaging, as well as of high-resolution integral field spectroscopy.

Methods. Narrow-band images acquired over a period of more than 21 yr were compared in order to study the expansion and evolution of all components of the R Aqr nebula. The magnification method was used to derive the kinematic ages of the features that appear to expand radially. Integral field spectroscopy of the [O III] 5007 Å emission is used to study the velocity structure of the central regions of the jet.

Results. New extended features, further out than the previously known hourglass nebula, are detected. The kinematic distance to R Aqr is calculated to be 178 pc using the expansion of the large hourglass nebula. This nebula of R Aqr is found to be roughly 650 yr old, while the inner regions have ages ranging from 125 to 290 yr. The outer nebula is found to be well described by a ballistic expansion, while for most components of the jet strong deviations from such behaviour are found. We find that the northern jet is mostly red-shifted while its southern part is blue-shifted, apparently at odds with findings from previous studies but almost certainly a consequence of the complex nature of the jet and variations in ionisation and illumination between observations.
The CARMENES search for exoplanets around M dwarfs
Authors: Fuhrmeister B. , Czesla S. , Schmitt J. H. M. M. , Jeffers S. V. , Caballero J. A. , Zechmeister M. , Reiners A. , Ribas I. , Amado P. J. , Quirrenbach A. , Béjar V. J. S. , Galadí-Enríquez D. , Guenther E. W. , Kürster M. , Montes D. , Seifert W.
Published: February 2018

Stellar activity is ubiquitously encountered in M dwarfs and often characterised by the Hαline. In the most active M dwarfs, Hαis found in emission, sometimes with a complex line profile. Previous studies have reported extended wings and asymmetries in the Hαline during flares. We used a total of 473 high-resolution spectra of 28 active M dwarfs obtained by the CARMENES (Calar Alto high-Resolution search for M dwarfs with Exo-Earths with Near-infrared and optical Echelle Spectrographs) spectrograph to study the occurrence of broadened and asymmetric Hαline profiles and their association with flares, and examine possible physical explanations. We detected a total of 41 flares and 67 broad, potentially asymmetric, wings in Hα. The broadened Hαlines display a variety of profiles with symmetric cases and both red and blue asymmetries. Although some of these line profiles are found during flares, the majority are at least not obviously associated with flaring. We propose a mechanism similar to coronal rain or chromospheric downward condensations as a cause for the observed red asymmetries; the symmetric cases may also be caused by Stark broadening. We suggest that blue asymmetries are associated with rising material, and our results are consistent with a prevalence of blue asymmetries during the flare onset. Besides the Hαasymmetries, we find some cases of additional line asymmetries in HeID3, NaID lines, and the HeIline at 10 830 Å taken all simultaneously thanks to the large wavelength coverage of CARMENES. Our study shows that asymmetric Hαlines are a rather common phenomenon in M dwarfs and need to be studied in more detail to obtain a better understanding of the atmospheric dynamics in these objects.
Using the CIFIST grid of CO5BOLD 3D model atmospheres to study the effects of stellar granulation on photometric colours
Authors: Kučinskas A. , Klevas J. , Ludwig H.-G. , Bonifacio P. , Steffen M. , Caffau E.
Published: February 2018

Aims. We studied the influence of convection on the spectral energy distributions (SEDs), photometric magnitudes, and colour indices of different types of stars across the H–R diagram.

Methods. The 3D hydrodynamical CO5BOLD, averaged ⟨3D⟩, and 1D hydrostatic LHD model atmospheres were used to compute SEDs of stars on the main sequence (MS), main sequence turn-off (TO), subgiant branch (SGB), and red giant branch (RGB), in each case at two different effective temperatures and two metallicities, [M∕H] = 0.0 and − 2.0. Using the obtained SEDs, we calculated photometric magnitudes and colour indices in the broad-band Johnson-Cousins UBVRI and 2MASS JHKs, and the medium-band Strömgren uvby photometric systems.

Results. The 3D–1D differences in photometric magnitudes and colour indices are small in both photometric systems and typically do not exceed ± 0.03 mag. Only in the case of the coolest giants located on the upper RGB are the differences in the U and u bands able reach ≈−0.2 mag at [M∕H] = 0.0 and ≈−0.1 mag at [M∕H] = −2.0. Generally, the 3D–1D differences are largest in the blue-UV part of the spectrum and decrease towards longer wavelengths. They are also sensitive to the effective temperature and are significantly smaller in hotter stars. Metallicity also plays a role and leads to slightly larger 3D–1D differences at [M∕H] = 0.0. All these patterns are caused by a complex interplay between the radiation field, opacities, and horizontal temperature fluctuations that occur due to convective motions in stellar atmospheres. Although small, the 3D–1D differences in the magnitudes and colour indices are nevertheless comparable to or larger than typical photometric uncertainties and may therefore cause non-negligible systematic differences in the estimated effective temperatures.
Leishmania infantum, Dirofilaria spp. and other endoparasite infections in kennel dogs in central Italy
Authors: Sauda Federica , Malandrucco Livia , Macrì Gladia , Scarpulla Manuela , De Liberato Claudio , Terracciano Giuliana , Fichi Gianluca , Berrilli Federica , Perrucci Stefania
Published: February 2018

Prevalence and risk factors of Leishmania infantum, Dirofilaria spp. and other potentially zoonotic or canine-specific endoparasite infections were assessed in 639 kennel dogs from central Italy. To this end, individual blood and fecal samples were examined using parasitological, immunological and molecular techniques. The presence of compatible clinical pictures, as well as age and gender were considered as putative risks factors. To evaluate risk factors, multivariable analysis with logistic regression and univariable analysis with a Chi square test and a Fischer’s exact test were performed. Overall, 52.6% of dogs (95% CI 48.6-56.5) were found positive, while 39.6% of dogs (95% CI 35.8-43.5) were infected by potentially zoonotic species. Leishmania infantum and Dirofilaria repens showed prevalences of 2.5% (95% CI 1.5-4.1) and 2.8% (95% CI 1.7-4.5), respectively. The prevalence of cardiorespiratory parasites was 7.8% (95% CI 5.9-10.3) and included the species Angiostrongylus vasorum, Eucoleus aerophilus, Eucoleus boehmi and D. immitis; the latter showed a prevalence of 0.2% (95% CI 0.001-1). Intestinal parasites were significantly prevalent (38.8%, 95% CI 35-42.7) and they consisted mainly of species of major zoonotic concern, including ancylostomatids, Toxocara canis, Giardia duodenalis, Dipylidium caninum, Taeniidae, Strongyloides stercoralis and Cryptosporidium parvum. Endoparasites were significantly prevalent in clinically suspected dogs. Leishmania infantum and cardiorespiratory nematodes were prevalent in older dogs, while intestinal parasites were prevalent in younger dogs. Results show high dog and public health risks in kennels in central Italy, and suggest the need for more effective control measures.
Palladium-Catalyzed Oxidation of Indoles to Isatins by tert-Butyl Hydroperoxide
Authors: Luo Junfei , Gao Shanshan , Ma Yaorui , Ge Guoping
Published: February 2018

The combination of a Pd catalyst and tert-butyl hydro­peroxide (TBHP) is a powerful catalytic system for many types of oxidative transformations. Here, we report that a Pd/TBHP system facilitates the oxidation of indoles with a range of functionalities to give the corresponding isatin derivatives in good yields.
Cycloaddition of Benzyne with Alkoxy-Substituted Pyrroline-N-oxides­: Unexpected Rearrangement to an N-Phenylpyrrole
Authors: Cordero Franca , Khairnar Bhushan , Ranzenigo Anna , Brandi Alberto
Published: February 2018

Reaction of enantiopure 3,4-dialkoxy-pyrroline N-oxides with benzyne affords the expected tetrahydrobenzo[d]pyrrolo[1,2-b]isoxazoles along with an unexpected 2,3-disubstitued-N-phenyl-pyrrole derived from an unprecedented rearrangement of the adduct of nitrone with two molecules of benzyne. A mechanism for the unusual rearrangement is proposed. The benzo[d]isoxazolidine derivatives are conveniently converted into 2-(2-hydroxyphenyl)-3,4-dialkoxypyrrolidines by reductive opening of the N–O bond.
The PCOS Patients differ in Lipid Profile According to their Phenotypes
Authors: Spałkowska Magdalena , Mrozińska Sandra , Gałuszka-Bednarczyk Anna , Gosztyła Katarzyna , Przywara Agnieszka , Guzik Justyna , Janeczko Marek , Milewicz Tomasz , Wojas-Pelc Anna
Published: February 2018

Polycystic ovary syndrome (PCOS) affects 4–18% of women of reproductive age. The number of reports exploring the lipid profiles among PCOS patients and number of studied patients are limited. The aim of our study was to assess the lipid profile separately in lean and non-lean women with polycystic ovary syndrome divided according to hyperandrogenemia, defined as free androgen index (FAI)≥5. The second aim was to compare the lipid profiles among lean and non-lean PCOS patients with respect to hyperandrogenemia and regularity of menstruation cycles. We evaluated 232 patients from Department of Endocrinological Gynecology, Jagiellonian University Medical College in Krakow diagnosed with PCOS. The population consisted of 166 lean and 66 non-lean women. We observed higher levels of total cholesterol, high-density lipoprotein cholesterol (HDL-C) in lean patients with FAI<5 than in lean patients with FAI≥5. There were no differences in lipid profile between non-lean patients with FAI≥5 and non-lean patients with FAI<5. Among lean patients higher total cholesterol levels were observed in those with irregular menstruation cycles and FAI<5 than in patients with FAI≥5 and regular cycles. There were no differences in lipid profiles between four phenotypes among non-lean PCOS patients.

Conclusions The results of our study showed differences in lipid profile between lean PCOS patients according to their phenotype based on androgens’ level. This effect was abandoned by fat tissue mass in non-lean ones. Further studies should be conducted to explore these associations.
Multiple convex demarcation line for prediction of benign depressed gastric lesions in magnifying narrow-band imaging
Authors: Kanesaka Takashi , Uedo Noriya , Yao Kenshi , Ezoe Yasumasa , Doyama Hisashi , Oda Ichiro , Kaneko Kazuhiro , Kawahara Yoshiro , Yokoi Chizu , Sugiura Yasushi , Ishikawa Hideki , Takeuchi Yoji , Arao Masamichi , Iwatsubo Taro , Iwagami Hiroyoshi , Matsuno Kenji , Muto Manabu , Saito Yutaka , Tomita Yasuhiko
Published: February 2018

Background and study aims With magnifying narrow-band imaging (M-NBI) of the gastric mucosa, a characteristic demarcation line (DL) is occasionally found in non-cancerous depressed lesions. This DL forms multiple convex shapes along the edge of the epithelia of surrounding mucosa. We have termed this novel finding a multiple convex DL (MCDL). In this study, we clarified the prevalence of an MCDL in depressed gastric lesions detected in patients at high risk for gastric cancer and determined the diagnostic yield necessary to distinguish between cancer and non-cancer.

Patients and methods This was a post hoc analysis of a multicenter prospective trial. In total, 362 small (≤ 10 mm) depressed lesions were detected in 1353 patients. Presence or absence of a DL in target lesions was evaluated on M-NBI images. The proportion of MCDLs among lesions with a DL was evaluated.

Results Images of 347 lesions (39 cancerous and 308 non-cancerous) were evaluable. A DL was present in 252/347 lesions (73 %). When the cutoff value for the proportion of MCDLs needed to distinguish non-cancer from cancer was set at two-thirds, an MCDL was observed in 86/252 lesions (34 %). In 86 lesions with an MCDL, 83 (97 %) were non-cancerous. The sensitivity, specificity, positive predictive value, and negative predictive value of an MCDL for non-cancerous lesions were 38 %, 91 %, 97 %, and 19 %, respectively.

Conclusions Presence of an MCDL had high specificity and positive predictive value for non-cancerous lesions. Evaluating the shape of the DL is useful for differentiation between cancer and non-cancerous lesions.
High complete resection rate for pre-lift and cold biopsy of diminutive colorectal polyps
Authors: O’Connor Sam , Brooklyn Trevor , Dunckley Paul , Valori Roland , Carr Ruth , Foy Chris , Somarathna Thusitha , Adamczyk Lukasz , Shepherd Neil , Anderson John
Published: February 2018

Background and study aims The majority of polyps removed at colonoscopy are diminutive (≤ 5 mm) to small (< 10 mm) and there are few guidelines for the best way for these polyps to be removed. We aimed to assess the feasibility and effectiveness of cold biopsy forceps polypectomy with pre-lift (CBPP) for polyps ≤ 7 mm. Our aims were to assess completeness of histological resection of this technique, to identify factors contributing to this and assess secondary considerations such as timing, retrieval and complication rates.

Patients and methods We conducted a prospective cohort study on consecutive patients receiving a colonoscopy at Cheltenham General Hospital, as part of the National Bowel Cancer Screening Program (BCSP) in England. The study included only polyps that were judged as ≤ 7 mm by the colonoscopist. A small sub-mucosal pre-lift injection was administered prior to removal of the polyp using cold biopsy forceps. One or more biopsies were taken until the polyp was confidently assessed visually as being completely removed by the colonoscopist. The entire polypectomy site was then removed en bloc by endomucosal resection (EMR) with a margin of at least 1 to 2 mm around defect. This was sent for histopathological analysis to assess completeness of resection. Polypectomy timing, tissue retrieval, number of bites required for visual resection and complications were recorded at the time of the procedure.

Results Sixty-four patients were recruited and consented. Of them, 42 patients had a total of 60 polyps resected. Three patients had inflammatory polyps and were excluded from the study, leaving 57/60 polyps for final analysis. Seventeen were hyperplastic and 40 adenomatous polyps. Retrieval was complete for all 57 polyps and there were no complications both during or post- polypectomy. The complete resection rate (CRR) was 86 %. The technique was more effective in smaller polyps with 91.7 % of diminutive polyps (≤ 5 mm) completely excised.

Conclusions CBPP is a safe and highly effective technique for polyps < 5 mm with a high complete resection and retrieval rate. The time taken for the procedure is significantly greater than cold forceps alone, or cold snare as seen in other studies.
Kombinierte Therapie der Endometriose: Radikal und schonend zugleich
Authors: Alkatout Ibrahim , Wedel Thilo , Maass Nicolai
Published: February 2018

Endometriose ist die zweithäufigste benigne Erkrankung des weiblichen Genitals nach der Leiomyomatose. Schwerpunkt dieser Übersicht ist die Darstellung des gynäkologischen Dilemmas zwischen medizinisch machbarem und für die individuelle Patientin sinnvollem Management. Im Vordergrund stehen die präoperative Diagnostik sowie die Planung der Operationsradikalität in Abhängigkeit des Leidensdruckes sowie des Kinderwunsches. Besonders herausgearbeitet werden die anatomischen Schnittmengenbereiche, die bei Verletzung zu (anhaltenden) Schädigungen des vorderen, mittleren und hinteren Kompartimentes führen können und damit nicht selten Ursache für urologische und urogynäkologische Folgemaßnahmen sind.

Zu den typischen Symptomen der Endometriose gehören: Dysmenorrhoe, chronische Unterbauchschmerzen, Dyspareunie, Subfertilität, unspezifische Unterbauchschmerzen, zyklische Darm- oder Blasensymptome (z. B. Dyschezie, Meteorismus, Obstipation, rektaler Blutabgang, Diarrhoen, Hämaturie), Blutungsstörungen oder chronische Müdigkeit.

Etwa 50 % aller weiblichen Jugendlichen und bis zu 32 % aller Frauen im reproduktionsfähigen Alter, die aufgrund chronischer Unterbauchschmerzen oder Dysmenorrhoe operiert werden; leiden an Endometriose. Das Zeitintervall zwischen den ersten unspezifischen Symptomen und der festen Diagnose beträgt bei der Endometriose etwa 7 Jahre. Hierfür ist nicht nur die ganz unspezifische Symptomatik verantwortlich, sondern v. a. auch die häufig fehlende Sensibilisierung der kooperierenden Fachdisziplinen, an die sich die Patientinnen im Erstkontakt wenden. Die Therapieoptionen beinhalten: Abwartendes Verhalten, Analgesie, hormonelle Therapie, operative Intervention und die Kombination aus Operation und medikamentöser Therapie. Die Rezidivrate für therapierte Endometriose liegt zwischen 5 % und > 60 % und ist stark abhängig von dem ganzheitlichen Management sowie der operativen Qualität. Zur Optimierung der individuellen Endometriosetherapie ist folglich Interdisziplinarität in Diagnostik und Therapie wegweisend und sollte v. a. bei der tief infiltrierenden Endometriose entsprechenden Zentren vorbehalten bleiben.
Chirurgische Therapie des urogenitalen Deszensus
Authors: Karapanos Leonidas , Salem Johannes , Akbarov Ilgar , Heidenreich Axel , Zugor Vahudin
Published: February 2018

Urogenitale Prolapserkrankungen sind mit hoher Prävalenz und unterschiedlicher Morbidität belastet. Klinisch imponieren Senkungs- und Miktionsbeschwerden mit Obstruktion, Drangsymptomatik und Begleitharninkontinenz. Die Prävalenz einer Beckenbodeninsuffizienz wird auf etwa 30 – 50 % geschätzt. Aufgrund der steigenden Lebenserwartungen und den damit verbundenen erhöhten Aktivitäten der Frauen ist sogar mit einem weiteren Anstieg der Senkungsinzidenz zu rechnen. Eine nicht geringe Zahl stellen dabei Rezidive dar. Schon heute zählen Operationen zur Therapie des Deszensus zu den häufigsten durchgeführten Operationen der Gynäkologie. In den USA werden jährlich über 220.000 Senkungsoperationen durchgeführt. Das Ziel der operativen Therapie ist die Behebung der jeweiligen Beschwerdesymptomatik mit konsekutiver Verbesserung der Lebensqualität. Ziel der Arbeit ist, die operativen Ergebnisse und Techniken unterschiedlicher Deszensuserkrankungen zu evaluieren und deskriptiv zu erfassen.
Critical Analysis of an e-Learning and Interactive Teaching Module with Respect to the Interpretation of Emergency Computed Tomography of the Brain
Authors: Groth Michael , Barthe Käthe , Riemer Martin , Ernst Marielle , Herrmann Jochen , Fiehler Jens , Buhk Jan-Hendrik
Published: February 2018

Purpose To compare the learning benefit of three different teaching strategies on the interpretation of emergency cerebral computed tomography (CT) pathologies by medical students.

Materials and Methods Three groups of students with different types of teaching (e-learning, interactive teaching, and standard curricular education in neuroradiology) were tested with respect to the detection of seven CT pathologies. The test results of each group were compared for each CT pathology using the chi-square test. A p-value ≤ 0.05 was considered to be significant.

Results Opposed to the results of the comparison group (curricular education), the e-learning group and interactive teaching tutorial group both showed a significantly better performance in detecting hyperdense middle cerebral artery sign (p = 0.001 and p < 0.0001) as well as subarachnoid hemorrhage (p = 0.03 and p = 0.001) on CT. Moreover, an increase in performance for the detection of subdural hematoma and skull fracture could be observed for both the interactive teaching group and the e-learning group, with statistical significance in the latter (p = 0.03 and p < 0.0001, respectively). No statistically significant differences were found for the detection of intracranial and epidural hemorrhage, as well as midline shift, among the groups studied.

Conclusion Our study demonstrates potential learning benefits for both the interactive teaching tutorial and e-learning module group with respect to reading CT scans with slightly different advantages. Thus, the introduction of new learning methods in radiological education might be reasonable at an undergraduate stage but requires learning content-based considerations.

Key points 

Citation Format
Diagnostik und Therapie vesikovaginaler und ureterovaginaler Fisteln
Authors: Lang Isabelle , Fisch Margit , Kluth Luis
Published: February 2018

Hintergrund Vesiko- und ureterovaginale Fisteln sind als unphysiologische Verbindungsgänge zwischen dem Harntrakt und dem Genitalsystem definiert. Obwohl sie weltweit eine der am häufigsten erworbenen Pathologien des Urogenitaltraktes darstellen, gibt es bis heute kein standardisiertes Vorgehen für die Diagnostik und Therapie. Dieses Review analysiert die gegenwärtige Fachliteratur zu vesiko- und ureterovaginalen Fisteln, um gängige diagnostische und therapeutische Konzepte aufzuzeigen.

Methoden Es erfolgte eine Literaturrecherche in den Datenbanken von Medline und PubMed, sowie darüber hinaus eine allgemeine Internetrecherche und die Auseinandersetzung mit Buchquellen. In der Folge wurden 40 wissenschaftliche Artikel, 4 Buchpublikationen und 1 Internetquelle als Grundlage verwandt.

Ergebnisse Die Diagnostik sollte sowohl für die vesiko- als auch für die ureterovaginale Fistel frühzeitig erfolgen und aus einer vaginalen Untersuchung, einer Zystoskopie und der Fisteldarstellung mit Methylenblau-Instillation bestehen. Zusätzlich lassen sich zur weiteren Differenzialdiagnostik der ureterovaginalen Fistel radiologische Untersuchungen durchführen. Die Therapien der beiden Fistelentitäten unterscheiden sich grundlegend. Die ureterovaginale Fistel wird zweizeitig versorgt. Im ersten Schritt wird eine Nierenfistel zur Entlastung der Niere und Urindrainage angelegt und in einem weiteren Schritt die Fistel verschlossen. Die Therapie der vesikovaginalen Fistel umfasst konservative und chirurgische Konzepte, wobei es transabdominale und/oder transvaginale Zugangswege gibt. Grundlegend sollten bei transabdominalem Zugang die Ureterostien identifiziert und ggf. geschient werden, bevor eine Exzision der Fistel erfolgt. Bei großen Fisteln besteht die Option der Interposition eines Lappens nach Mobilisation des umliegenden Gewebes. Nahezu alle operativen Techniken gehen mit hohen Erfolgsraten einher. Ausnahmen sind bestrahlte Patienten, bei denen in schweren Fällen eine Harnableitung erfolgen muss.

Schlussfolgerungen Es bestehen weiterhin starke Unterschiede in der Entstehung von Fisteln und der operativen Versorgung zwischen Entwicklungs- und Industrieländern. Die entwickelten, operativen Verfahren haben unabhängig vom Zugangsweg hohe Erfolgsraten. Das Therapiekonzept sollte abhängig von der Ätiologie, Lage und Größe der Fistel und Gewebevoraussetzungen individuell entwickelt werden.
GSK-3 Inhibitors: A Double-Edged Sword? – An Update on Tideglusib
Authors: Mathuram Theodore , Reece Lisa , Cherian Kotturathu
Published: February 2018

GSK-3 inhibitors are an emerging tool for clinical interventions in human diseases and represent a niche area in combinational therapy. They possess diverse facets in applications of nervous system disorders, Type 2 diabetes, regenerative medicine and cancer. However, conflicting reports suggest the controversial role of GSK-3 inhibitors in cancers. This review aims to highlight the rise of GSK-3 inhibitors as tools for molecular-targeted research and its shift to a promising drug candidate. The review also focuses on key GSK-3 inhibitors and their roles in cancer and regenerative medicine with special emphasis to tideglusib. In addition, the decisive roles of GSK-3 in various molecular pathways will be concisely reviewed. Finally, this review concludes the emergence of GSK-3 inhibitors as a ‘double-edged sword’ in the treatment against human diseases cautioning researchers about the potential ramifications of off-target pharmacological effects.
Imaging the Unimaginable: Desorption Electrospray Ionization – Imaging Mass Spectrometry (DESI-IMS) in Natural Product Research
Authors: Parrot Delphine , Papazian Stefano , Foil Daniel , Tasdemir Deniz
Published: February 2018

Imaging mass spectrometry (IMS) has recently established itself in the field of “spatial metabolomics.” Merging the sensitivity and fast screening of high-throughput mass spectrometry with spatial and temporal chemical information, IMS visualizes the production, location, and distribution of metabolites in intact biological models. Since metabolite profiling and morphological features are combined in single images, IMS offers an unmatched chemical detail on complex biological and microbiological systems. Thus, IMS-type “spatial metabolomics” emerges as a powerful and complementary approach to genomics, transcriptomics, and classical metabolomics studies. In this review, we summarize the current state-of-the-art IMS methods with a strong focus on desorption electrospray ionization (DESI)-IMS. DESI-IMS utilizes the original principle of electrospray ionization, but in this case solvent droplets are rastered and desorbed directly on the sample surface. The rapid and minimally destructive DESI-IMS chemical screening is achieved at ambient conditions and enables the accurate view of molecules in tissues at the µm-scale resolution. DESI-IMS analysis does not require complex sample preparation and allows repeated measurements on samples from different biological sources, including microorganisms, plants, and animals. Thanks to its easy workflow and versatility, DESI-IMS has successfully been applied to many different research fields, such as clinical analysis, cancer research, environmental sciences, microbiology, chemical ecology, and drug discovery. Herein we discuss the present applications of DESI-IMS in natural product research.
Prescription of Benzodiazepines and Related Drugs in Patients with Mild Cognitive Deficits and Alzheimer’s Disease
Authors: Hessmann Philipp , Dodel Richard , Baum Erika , Müller Matthias , Paschke Greta , Kis Bernhard , Zeidler Jan , Klora Mike , Reese Jens-Peter , Balzer-Geldsetzer Monika
Published: February 2018

Introduction Benzodiazepines and related drugs (BZDR) should be avoided in patients with cognitive impairment. We evaluated the relationship between a BZDR treatment and the health status of patients with Alzheimer’s disease (AD).

Methods Cross-sectional study in 395 AD patients using bivariate and multiple logistic analyses to assess correlations between the prescription of BZDR and patients’ characteristics (cognitive and functional capacity, health-related quality of life (HrQoL), neuropsychiatric symptoms).

Results BZDR were used in 12.4% (n=49) of all participants. In bivariate analyses, the prescription was associated with a lower HrQoL, a higher need of care, and the presence of anxiety. Multivariate models revealed a higher risk of BZDR treatment in patients with depression (OR 3.85, 95% CI: 1.45 – 10.27). Community-dwelling participants and those treated by neurologists/psychiatrists had a lower risk of receiving BZDR (OR 0.33, 95% CI: 0.12 – 0.89 and OR 0.16, 95% CI: 0.07 – 0.36).

Discussion The inappropriate use of BZDR conflicts with national and international guidelines. We suggest evaluating indications and treatment duration and improving the knowledge of alternative therapies in healthcare institutions.