bluuebunny/crossref_metadata_2025 huggingface dataset:
Процессы рождения электрон-позитронной плазмы нейтрино высоких энергий в сильном магнитном поле
Authors: Gvozdev Aleksandr Aleksandrovich , Osokina Elena Vladimirovna
Published: September 2015

В условиях гипераккреционного сильно замагниченного диска керровской черной дыры исследованы процессы $\nu_i+\tilde\nu_i\to e^-+e^+$, $\nu_i(\tilde\nu_i)\stackrel{B}{\longrightarrow} \nu_i(\tilde\nu_i)+e^++e^-$ рождения электрон-позитронной плазмы в окрестности диска. Эффективность рождения плазмы в данных процессах вычислена при известных параметрах нейтринного излучения из диска, распределение магнитного поля задавалось из качественных соображений. Показано, что в случае $\omega^2\gg eB\gg m_e^2$ можно пренебречь влиянием магнитного поля на сечение процесса аннигиляции $\nu_i+\tilde\nu_i\to e^-+e^+$. Показано также, что эффективность производства энергии-импульса в $e^+e^-$-плазме в реакции $\nu_i(\tilde\nu_i)\stackrel{B}{\longrightarrow} \nu_i(\tilde\nu_i)+e^++e^-$ существенно зависит от распределения магнитного поля в диске. Таким образом, для окончательной оценки эффективности рождения плазмы в данной реакции необходимо задать распределение сильного магнитного поля в окрестности нейтриноизлучающей части диска.
Сшивка ветвей непертурбативного конформного блока на его дивизоре сингулярностей
Authors: Itoyama Hiroshi , Mironov Andrei Dmitrievich , Morozov Aleksei Yur'evich
Published: September 2015

Конформный блок является функцией многих переменных, которая обычно представляется в виде формального ряда с коэффициентами, являющимися некоторыми матричными элементами в киральной алгебре (т. е. в алгебре Вирасоро). Непертурбативный конформный блок есть многозначная функция, определенная на пространстве размерностей, со многими ветвями и, возможно, с дополнительными свободными параметрами, не видными на пертурбативном уровне. Обсуждаются дополнительные усложнения непертурбативного описания, возникающие по причине того, что все наилучшим образом изученные примеры лежат на локусе сингулярностей в пространстве модулей (на дивизоре коэффициентов или просто в нулях детерминанта Каца). Типичным примером является точка Ашкина-Теллера, где имеются по меньшей мере два непертурбативных выражения, заданных эллиптическим интегралом Доценко-Фатеева и знаменитой формулой Ал. Замолодчикова в терминах тета-констант. Эти выражения различны. Ситуация в некотором роде напоминает модель Изинга и другие точки минимальных моделей.
Квантовые $R$-матрицы Бакстера-Белавина и многомерные пары Лакса для уравнения Пенлеве VI
Authors: Levin Andrei Mikhailovich , Olshanetsky Mikhail Aronovich , Zotov Andrei Vladimirovich
Published: September 2015

Квантовые эллиптические $R$-матрицы удовлетворяют ассоциативному уравнению Янга-Бакстера в $\mathrm{Mat}(N)^{\otimes 2}$, которое можно рассматривать как некоммутативный аналог тождеств Фэя для скалярной функции Кронекера. Представлен более широкий список $R$-матричнозначных тождеств для эллиптических функций. В частности, предложен аналог тождеств Фэя в пространстве $\mathrm{Mat}(N)^{\otimes 2}$, а также описано представление для $R$-матриц в виде двойных рядов Кронекера. В качестве приложения с помощью ($\mathbb{Z}_N\times\mathbb{Z}_N$)-симметричной эллиптической $R$-матрицы построены $R$-матричнозначные ($2N^2\times 2N^2$)-пары Лакса для уравнения Пенлеве VI (в эллиптической форме) с четырьмя произвольными константами. Более точно, случай четырех произвольных констант отвечает нечетным $N$, а четные $N$ соответствуют случаю единственной константы в уравнении.
О свойствах многочленов от случайных элементов
Authors: Ulyanov Vladimir Vasilievich
Published: September 2015

В работе рассматриваются различные свойства многочленов от случайных элементов: оценки характеристических функционалов многочленов, стохастическое обобщение теоремы Виноградова о среднем, характеризационная проблема, оценка вероятностей попадания в шары. При этом результаты охватывают случайные элементы со значениями как в конечномерных, так и в бесконечномерных гильбертовых пространствах.
Calculations of automatic chamber flux measurements of methane and carbon dioxide using short time series of concentrations
Authors: Pirk N. , Mastepanov M. , Parmentier F.-J. W. , Lund M. , Crill P. , Christensen T. R.
Published: September 2015

Abstract. The closed chamber technique is widely used to measure the exchange of methane (CH4) and carbon dioxide (CO2) from terrestrial ecosystems. There is, however, large uncertainty about which model should be used to calculate the gas flux from the measured gas concentrations. Due to experimental uncertainties the robust linear regression model (first order polynomial) is often applied, even though theoretical considerations of the technique suggest the application of other, curvilinear models. High-resolution automatic chamber systems which sample gas concentrations several hundred times per flux measurement make it possible to resolve the curvilinear behavior and study the information imposed by the natural variability of the temporal concentration changes. We used more than 50 000 such flux measurements of CH4 and CO2 from five field sites located in peat forming wetlands to calculate fluxes with different models. The flux differences from independent linear estimates are generally found to be smaller than the local flux variability on the plot scale. The curvilinear behavior of the gas concentrations within the chamber is strongly influenced by wind driven chamber leakage, and less so by changing gas concentration gradients in the soil during chamber closure. Such physical processes affect both gas species equally, which makes it possible to isolate biochemical processes affecting the gases differently, such as photosynthesis limitation by chamber headspace CO2 concentrations under high levels of incoming solar radiation. We assess the possibility to exploit this effect for a partitioning of the net CO2 flux into photosynthesis and ecosystem respiration and argue that high-resolution automatic chamber measurements could be used for purposes beyond the estimation of the net gas flux.
Benthic foraminifera at the Paleocene/Eocene thermal maximum in the western Tethys (Forada section): variability in climate and productivity
Authors: Giusberti L. , Boscolo Galazzo F. , Thomas E.
Published: September 2015

Abstract. The Forada section (northeastern Italy) provides a continuous, expanded deep-sea record of the Paleocene/Eocene thermal maximum (PETM) in the central-western Tethys. We combine a new, high resolution, benthic foraminiferal assemblage record with published calcareous plankton, mineralogical and biomarker data to document climatic and environmental changes across the PETM, highlighting the benthic foraminiferal extinction event (BEE). The onset of the PETM, occurring ~ 30 kyr after a precursor event, is marked by a thin, black, barren clay layer, possibly representing a brief pulse of anoxia and carbonate dissolution. The BEE occurred within the 10 cm interval including this layer. During the first 3.5 kyr of the PETM several agglutinated recolonizing taxa show rapid species turnover, indicating a highly unstable, CaCO3-corrosive environment. Calcareous taxa reappeared after this interval, and the next ~ 9 kyr were characterized by rapid alternation of peaks in abundance of various calcareous and agglutinant recolonizers. These observations suggest that synergistic stressors including deep water CaCO3-corrosiveness, low oxygenation, and high environmental instability caused the extinction. Combined faunal and biomarker data (BIT index, higher plant n-alkane average chain length) and the high abundance of the mineral chlorite suggest that erosion and weathering increased strongly at the onset of the PETM, due to an overall wet climate with invigorated hydrological cycle, which led to storm flood-events carrying massive sediment discharge into the Belluno Basin. This interval was followed by the core of the PETM, characterized by four precessionally paced cycles in CaCO3%, hematite%, δ13C, abundant occurrence of opportunistic benthic foraminiferal taxa, as well as calcareous nannofossil and planktonic foraminiferal taxa typical of high productivity environments, radiolarians, and lower δDn-alkanes. We interpret these cycles as reflecting alternation between an overall arid climate, characterized by strong winds and intense upwelling, with an overall humid climate, with abundant rains and high sediment delivery (including refractory organic carbon) from land. Precessionally paced marl-limestone couplets occur throughout the recovery interval of the CIE and up to ten meters above it, suggesting that these wet-dry cycles persisted, though at declining intensity, after the peak PETM. Enhanced climate extremes at mid-latitudes might have been a direct response to the massive CO2 input in the ocean atmosphere system at the Paleocene–Eocene transition, and may have had a primary role in restoring the Earth system to steady state.
Geographien zwischen Diskurs und Praxis – Mit Wittgenstein Anknüpfungspunkte von Diskurs- und Praxistheorie denken
Authors: Baumann C. , Tijé-Dra A. , Winkler J.
Published: September 2015

Abstract. Current discussions about a practice turn in human geography raise questions about whether discourse analytical approaches are focusing too strongly on symbolic representations. However, practice-theoretical conceptions privilege the analysis of everyday practices, discussing issues of embodiment and materiality. Following the considerations of Ludwig Wittgenstein, we assume certain connections between these two fields of study and explore the links between discourse and practice theory by employing the Wittgensteinian concepts of language-games and rule-following. Focussing on the discourse theory of Laclau and Mouffe and the practice theory of Schatzki, we show to what extend both theories are informed by Wittgenstein's work and can be seen as different types of language-games analyses. We highlight the similarities and discuss the differences in the basic interests of these theories. Finally, we introduce an integrative „Wittgensteinian approach“ that is illustrated by two empirical examples of geographical inquiry – practices of a new rurality and rap-music in stigmatized banlieus.
Impact of two different types of El Niño events on runoff over the conterminous United States
Authors: Tang T. , Li W. , Sun G.
Published: September 2015

Abstract. The responses of river runoff to shifts of large-scale climatic patterns are of increasing concerns to water resource planners and managers for long-term climate change adaptation. El Niño is one of the most dominant modes of climate variability that is closely linked to hydrologic extremes such as floods and droughts that cause great loss of lives and properties. However, the different impacts of the two types of El Niño-Central Pacific (CP) and Eastern Pacific (EP)-El Niño on runoff across the conterminous US (CONUS) are not well understood. This study characterizes the impacts of the CP- and EP-El Niño on seasonal and annual runoff using observed historical streamflow data from 658 reference gaging stations and NCAR-CCSM4 model. We found that surface runoff responds similarly to the two types of El Niño events in Southeast, Central, South and Western coastal regions, but differently in Northeast (NE), Pacific Northwest (PNW) and West North Central (WNC) climatic zones. Specifically, EP-El Niño events tend to bring above-average runoff in NE, WNC, and PNW throughout the year while CP-El Niño events cause below-than normal runoff in the three regions. Similar findings were also found by analyzing NCAR-CCSM4 model outputs that captured both the CP- and EP-El Niño events representing the best datasets among selected CMIP5 models. The CCSM4 model simulates lower runoff values during CP-El Niño years than those in EP-El Niño in all of the three climatic regions (NE, PNW and WNC) during 1950–1999. In the future (2050–2099), for both types of El Niño years, runoff is projected to increase over the NE and PNW regions, mainly due to increased precipitation (P). In contrast, the increase of future evapotranspiration (ET) is higher than that of future P, leading to a projected decrease in runoff over the WNC region. In addition, model analysis indicates that all of the three regions (NE, PNW and WNC) are projected to have lower runoff values during CP-El Niño years than EP-El Niño. Our study suggests that US water resources may be distributed more unevenly in space and time with more frequent and intense flood and drought events. The findings from this study have important implications to water resource management at the regional scale. Information generated from this study is useful for water resource planners to anticipate the influence of two different types of El Niño events on droughts and floods across the CONUS.
Statistical properties of coastal long waves analysed through sea-level time-gradient functions: exemplary analysis of the Siracusa, Italy, tide-gauge data
Authors: Bressan L. , Tinti S.
Published: September 2015

Abstract. This study presents a new method to analyse the properties of the sea-level signal recorded by coastal tide gauges in the long wave range that is in a window between wind/storm waves and tides and is typical of several phenomena like local seiches, coastal shelf resonances and tsunamis. The method consists of computing four specific functions based on the time gradient (slope) of the recorded sea level oscillations, namely the instantaneous slope IS, and three more functions based on IS, that are the sea level SL, the background slope BS and the control function CF. These functions are examined through a traditional spectral FFT analysis and also through a statistical analysis showing that they can be characterised by probability distribution functions PDFs such as the Student's t distribution (IS and SL) and the Beta distribution (CF). As an example, the method has been applied to data from the tide-gauge station of Siracusa, Italy.
Not “Just Another Brick in the Wall”
Authors: Zolkower Betina A. , Rubel Laurie H.
Published: September 2015

A vignette from a middle school classroom discusses how “low threshold, high ceiling” number puzzles will intrigue and interest students and teachers.
Just Say Yes to Early Algebra!
Authors: Stephens Ana , Blanton Maria , Knuth Eric , Isler Isil , Gardiner Angela Murphy
Published: September 2015

Researchers find that these classroom activities and instructional strategies support the development of third-grade students' algebraic thinking.
Division Quilts: A Measurement Model
Authors: Pratt Sarah S. , Lupton Tina M. , Richardson Kerri
Published: September 2015

Students can create an image of the measurement model of division as an alternative to the long division algorithm.
Number Link Challenges
Authors: Klemm Rebecca
Published: September 2015

Take students on a scavenger hunt in the school or classroom, or on the playground—or have them do it at home—and help them find numbers in real life. They can take photos or draw the number links they see, such as shape (triangles for three), name (classroom 4), quantity (six windows), or order (first-place ribbon).
Structure of a bacterial RNA polymerase holoenzyme open promoter complex
Authors: Bae Brian , Feklistov Andrey , Lass-Napiorkowska Agnieszka , Landick Robert , Darst Seth A
Published: September 2015

Initiation of transcription is a primary means for controlling gene expression. In bacteria, the RNA polymerase (RNAP) holoenzyme binds and unwinds promoter DNA, forming the transcription bubble of the open promoter complex (RPo). We have determined crystal structures, refined to 4.14 Å-resolution, of RPo containing Thermus aquaticus RNAP holoenzyme and promoter DNA that includes the full transcription bubble. The structures, combined with biochemical analyses, reveal key features supporting the formation and maintenance of the double-strand/single-strand DNA junction at the upstream edge of the −10 element where bubble formation initiates. The results also reveal RNAP interactions with duplex DNA just upstream of the −10 element and potential protein/DNA interactions that direct the DNA template strand into the RNAP active site. Addition of an RNA primer to yield a 4 base-pair post-translocated RNA:DNA hybrid mimics an initially transcribing complex at the point where steric clash initiates abortive initiation and σA dissociation.
Using RAxML to Infer Phylogenies
Authors: Stamatakis Alexandros
Published: September 2015

Inference of phylogenetic trees under the maximum likelihood (ML) criterion represents a routine task in biological data analysis. In this unit we describe how to plan analyses and use Randomized Accelerated Maximum Likelihood (RAxML) for phylogenetic inferences under ML, how to infer support values using the standard bootstrap procedure as well as other statistical measures, and how to conduct post‐analyses on collections/sets of phylogenetic trees including statistical significance tests and consensus tree methods. We also discuss what measures can be taken and what further analyses can be conducted when relationships in the inferred tree exhibit “low” support. © 2015 by John Wiley & Sons, Inc.
Cloud organization and growth during the transition from suppressed to active MJO conditions
Authors: Rowe Angela K. , Houze Robert A.
Published: September 2015

During the Dynamics of the Madden‐Julian Oscillation/Atmospheric Radiation Measurement Madden‐Julian Oscillation (MJO) Investigation Experiment field experiment in the Indian Ocean, the National Center for Atmospheric Research dual‐polarimetric S‐ and Ka‐band radar (S‐PolKa) radar observed three active Madden‐Julian Oscillation (MJO) events. These events were separated by suppressed periods characterized by shallower, more isolated convection and relatively little rainfall. The sensitivity of S‐PolKa allowed investigation of the initiation and organization of both nonprecipitating and precipitating clouds. Early in the suppressed periods, shallow nonprecipitating clouds occurred in shear‐parallel lines along apparent boundary layer rolls during early morning. Once some of the clouds began to precipitate, small cold pools formed below the showers. By afternoon, the lines all but disappeared with nonprecipitating clouds instead forming along the edges of cold pools. All such convection was limited in depth early in suppressed periods. As the suppressed environment gained moisture, the nonprecipitating clouds were able to grow to larger size, with the deepest precipitating clouds occurring in clusters at intersections of cold pool boundaries by afternoon. Upscale growth into mesoscale convective systems was observed as the suppressed periods transitioned into active MJO phases, contributing to overnight precipitation during the later part of the suppressed period. This study demonstrates the need for models to accurately represent the organization and evolution of nonprecipitating clouds in association with boundary layer dynamics under suppressed conditions of the MJO, prior to the occurrence of precipitating clouds and their cold pools.
Ice thickness in the Northwest Passage
Authors: Haas Christian , Howell Stephen E. L.
Published: September 2015

Recently, the feasibility of commercial shipping in the ice‐prone Northwest Passage (NWP) has attracted a lot of attention. However, very little ice thickness information actually exists. We present results of the first ever airborne electromagnetic ice thickness surveys over the NWP carried out in April and May 2011 and 2015 over first‐year and multiyear ice. These show modal thicknesses between 1.8 and 2.0 m in all regions. Mean thicknesses over 3 m and thick, deformed ice were observed over some multiyear ice regimes shown to originate from the Arctic Ocean. Thick ice features more than 100 m wide and thicker than 4 m occurred frequently. Results indicate that even in today's climate, ice conditions must still be considered severe. These results have important implications for the prediction of ice breakup and summer ice conditions, and the assessment of sea ice hazards during the summer shipping season.
Dramatically increased rate of observed hot record breaking in recent Australian temperatures
Authors: Lewis Sophie C. , King Andrew D.
Published: September 2015

Persistent extreme temperatures were observed in Australia during 2012–2014. We examine changes in the rate of hot and cold record breaking over the observational record for Australia‐ and State‐wide temperatures. The number of new hot (high‐maximum and high‐minimum temperatures) temperature records increases dramatically in recent decades, while the number of cold records decreases. In a stationary climate, cold and hot records are expected to occur in equal frequency on longer than interannual time scales; however, during 2000–2014, new hot records outnumber new cold records by 12 to one on average. Coupled Model Intercomparison Project phase 5 experiments reveal increased hot temperature record breaking occurs in simulations that impose anthropogenic forcings but not in natural forcings‐only experiments. This disproportionate hot to cold record breaking rates provides a useful indicator of nonstationarity in temperatures, which is related to the underlying mean observed Australian warming trend of 0.9°C since high‐quality records began in 1910.
Mechanical behavior and microstructure of simulated calcite fault gouge sheared at 20–600°C: Implications for natural faults in limestones
Authors: Verberne Berend A. , Niemeijer André R. , De Bresser Johannes H. P. , Spiers Christopher J.
Published: September 2015

We report ring shear experiments on simulated calcite fault gouges performed at fixed temperatures (T) within the range from 20°C to 600°C. The experiments were performed wet, using pore fluid pressures (Pf) of 10 ≤ Pf ≤ 60 MPa. One series of experiments employed a constant effective normal stress (
) of 50 MPa, while in a second series,
was sequentially stepped from 30 to 100 MPa. In all experiments, sliding velocity (v) was stepped in the range from 0.03 to 100 µm/s. The results showed stable, velocity‐strengthening behavior at 20°C, but velocity weakening at 100°C to 550°C (for all v steps to <3 µm/s), which was frequently accompanied by stick slip. At 600°C, velocity strengthening occurred. Microstructural observations suggest increasing importance of ductile deformation with increasing temperature, as reflected by a localized shear band structure at 20°C giving way to a pervasive, shear plane‐parallel grain shape fabric at 600°C. Using existing flow equations for dense calcite polycrystals, we show that dislocation and/or diffusion creep of 10–30 µm‐sized bulk gouge grains likely played a role in experiments performed at T ≥ 400°C. We suggest that the observed velocity‐weakening behavior can be explained by a slip mechanism involving dilatant granular flow in competition with creep‐controlled compaction. Our results have important implications for the breadth of the seismogenic zone in limestone terrains and for the interpretation of natural fault rock microstructures. Specifically, while samples sheared at 400–550°C exhibited essentially brittle/frictional mechanical behavior (stick slip), the corresponding microstructures resembled that of a mylonite.
Isotopic composition and speciation of sedimentary nitrogen and carbon in the Okinawa Trough over the past 30 ka
Authors: Zheng Li‐Wei , Hsiao Silver Sung‐Yun , Ding Xiao‐Dong , Li Dawei , Chang Yuan‐Pin , Kao Shuh‐Ji
Published: September 2015

Total organic carbon to total nitrogen ratios (C/N) and their isotopic compositions (δ13CTOC and δ15NTN) are oft‐applied proxies to discern terrigenous from marine‐sourced organics and to unravel ancient environmental information. In high depositional Asian marginal seas, the inclusion of N‐bearing minerals in the bulk sediment dilutes or masks signals sought after in δ15N and δ13C analyses, thus leading to incorrect and even contradictory interpretations. We used KOH‐KOBr to separate operationally defined total organic matter into oxidizable (labile) and residual fractions for content and isotope measurements. In a sediment core in the Okinawa Trough, significant amounts of carbon and nitrogen existed in the residual phase, in which the C/N ratio was ~9, resembling most documented sedimentary bulk C/N ratios in the China marginal seas. The residual carbon, which was included in operationally defined total organic carbon (TOC), displayed a δ13C range (−22.7 to −18.9‰, mean −20.7‰) similar to the oft‐used marine end‐member. After removing the interference from the residual fraction, we found that the temporal pattern of δ13CLOC (LOC denotes labile organic carbon) was more variable. The residual nitrogen content was associated with illite, suggesting a terrestrial origin. Additionally, δ15N in the residual fraction likely reflected the climatic controls (e.g., precipitation) on lithogenic source materials. Further studies are required to explore the controlling factors for carbon and nitrogen isotopic speciation and to retrieve the information locked in the residual fraction.
A unique TBX5 microdeletion with microinsertion detected in patient with Holt–Oram syndrome
Authors: Morine Mikio , Kohmoto Tomohiro , Masuda Kiyoshi , Inagaki Hidehito , Watanabe Miki , Naruto Takuya , Kurahashi Hiroki , Maeda Kazuhisa , Imoto Issei
Published: September 2015

Holt–Oram syndrome (HOS) is an autosomal dominant condition characterized by upper limb and congenital heart defects and caused by numerous germline mutations of TBX5 producing preterminal stop codons. Here, we report on a novel and unusual heterozygous TBX5 microdeletion with microinsertion (microindel) mutation (c.627delinsGTGACTCAGGAAACGCTTTCCTGA), which is predicted to synthesize a truncated TBX5 protein, detected in a sporadic patient with clinical features of HOS prenatally diagnosed by ultrasonography. This uncommon and relatively large inserted sequence contains sequences derived from nearby but not adjacent templates on both sense and antisense strands, suggesting two possible models, which require no repeat sequences, causing this complex microindel through the bypass of large DNA adducts via an error‐prone DNA polymerase‐mediated translesion synthesis. © 2015 Wiley Periodicals, Inc.
Smoking is an independent association of squamous metaplasia in Chinese nasal polyps
Authors: Gao Tian , Ng Chew Lip , Li Chunwei , Li Ying Ying , Duan Chen , Shen Liang , Jiao Yu Fei , Liu Ming , Wang De Yun
Published: September 2015

Background

Nasal polyposis demonstrates histological features of epithelial remodeling and variable inflammatory cellular infiltration. We studied a large series of Chinese nasal polyp (NP) samples to characterize these histological features and their associations with clinical characteristics.

Methods

A detailed histological study of nasal polyposis was performed employing various histopathological techniques. A total of 153 intraoperative NP biopsies were analyzed histologically. Sections were examined under microscopy to determine the percentages of different types of inflammatory cells, and types of epithelial remodeling. Two systems of subtyping NPs based on inflammatory cell infiltration were assessed. These were correlated with patient characteristics.

Results

Epithelial remodeling patterns include epithelial hyperplasia (87.8% of specimens), goblet cell hyperplasia (53.2%), and squamous metaplasia (44.6%). Smoking was a strong independent association of squamous metaplasia (adjusted odds ratio [OR] 9.9; 95% confidence interval [CI], 4.2 to 22.9; p < 0.01). The most common inflammatory cells were neutrophils (median of 12.8%) and CD8+ T cells (12.8%), followed by macrophages (11.0%), CD4+ T cells (9.7%), eosinophils (8.6%), and mast cells (7.6%). We defined 2 systems to classify NPs based on proportions of eosinophils and neutrophils. The majority of NP samples were neutrophilic. The first classification system has greater histological correlation. Based on the first classification, eosinophilic nasal polyposis was associated with epithelial hyperplasia (OR 3.7, p = 0.019) and goblet cell hyperplasia (OR 3.4, p < 0.001).

Conclusion

The majority of Chinese NPs are neutrophilic and epithelial hyperplasia is the most common pattern of epithelial remodeling. We show for the first time that smoking has a strong association with squamous metaplasia in nasal polyposis.
Hyperdense findings in sinus computed tomography of chronic rhinosinusitis
Authors: Ng Teik‐Ying , Wang Jong‐Yi , Tsai Ming‐Hsui , Lin Chao‐Chun , Tai Chih‐Jaan , Ng Yon‐Keat
Published: September 2015

Background

Our study investigated the diagnostic value of the mineralization findings and high‐density secretion features of sinus computed tomography (CT) images in cases of chronic rhinosinusitis (CRS) compared to histopathology and operative findings.

Methods

This was a prospective cohort study of 193 patients consecutively enrolled for endoscopic sinus surgery (ESS). Group 1 had mineralization in the sinus; group 2 had high‐density secretions in the sinus but no mineralization; group 3 lacked both high‐density secretions and evidence of mineralization. Intergroup comparisons were performed for histopathology (especially presence of fungus ball), CT scores, and gross operative appearance.

Results

Histopathologic evidence of fungus ball (FB) compared to presence of CT findings was significantly different between the groups, with the following percentages of patients demonstrating FB presence: 33% of group 1 (CT mineralization) (n = 48); 4% of group 2 (CT hyperdensity) patients (n = 25); and 2% of group 3 (no mineralization, no hyperdensity) patients (n = 120) (p < 0.05). Operative findings did not necessarily correlate with CT findings and all groups demonstrated varying amounts of dry cheesy (DCM) or wet clay‐like (WCLM) material, though this was slightly higher in groups 1 and 2.

Conclusion

A preoperative survey of sinus mineralization and high‐density secretion features observed with CT was predictive of operative findings and histopathological results indicating a sinus FB.
Eine Hot‐Spot‐Segmentstrategie zum Entwurf von Mimetika der Kreuzamyloid‐Interaktionsflächen als Amyloidinhibitoren
Authors: Andreetto Erika , Malideli Eleni , Yan Li‐Mei , Kracklauer Michael , Farbiarz Karine , Tatarek‐Nossol Marianna , Rammes Gerhard , Prade Elke , Neumüller Tatjana , Caporale Andrea , Spanopoulou Anna , Bakou Maria , Reif Bernd , Kapurniotu Aphrodite
Published: September 2015

Der Entwurf von Inhibitoren von Protein‐Protein‐Wechselwirkungen, die die amyloidogene Selbstassemblierung herbeiführen, ist ein sehr anspruchsvolles Vorhaben. Dies liegt an der dynamischen Natur der beteiligten Strukturen und Proteinflächen. Die Wechselwirkungen von amyloidogenen Polypeptiden mit anderen Proteinen sind wichtige Modulatoren ihrer Selbstassoziation. Hier stellen wir eine Hot‐Spot‐Segmentverknüpfungsstrategie zum Entwurf einer Serie von Mimetika der IAPP‐Kreuzinteraktionsfläche mit Aβ (ISMs) als nanomolare Inhibitoren der Amyloidogenese und Zelltoxizität von Aβ, IAPP oder beiden Polypeptiden vor. Dabei bestimmt die Natur des Verknüpfungselements die Struktur der ISMs und ihre inhibitorische Funktion, im Bezug auf sowohl Inhibitorpotenz als auch Zielmolekül‐Selektivität. Die ISMs sind außerdem in der Lage, zusätzlich zur Selbst‐ auch die kreuznukleierte IAPP‐Selbstassoziation effektiv zu unterdrücken. Unsere Ergebnisse bieten eine neuartige Klasse von hochpotenten Peptidleitstrukturen, die auf die Hemmung der Proteinaggregation in der Alzheimer‐Krankheit, dem Typ‐2‐Diabetes oder beiden Krankheiten abzielt, sowie eine chemische Strategie zur Inhibition der amyloiden Selbstassoziation und der pathogenenen Wechselwirkungen auch anderer Proteine.
Scalable Synthesis of Piperazines Enabled by Visible‐Light Irradiation and Aluminum Organometallics
Authors: Suárez‐Pantiga Samuel , Colas Kilian , Johansson Magnus J. , Mendoza Abraham
Published: September 2015

The development of more active CH oxidation catalysts has inspired a rapid, scalable, and stereoselective assembly of multifunctional piperazines through a [3+3] coupling of azomethine ylides. A combination of visible‐light irradiation and aluminum organometallics is essential to promote this transformation, which introduces visible‐light photochemistry of main‐group organometallics and sets the basis for new and promising catalysts.
Isolierung und Charakterisierung Lewis‐Base‐stabilisierter monomerer Stammverbindungen der Stibanylborane
Authors: Marquardt Christian , Hegen Oliver , Hautmann Matthias , Balázs Gábor , Bodensteiner Michael , Virovets Alexander V. , Timoshkin Alexey Y. , Scheer Manfred
Published: September 2015

Wir berichten über die Synthese der Lewis‐Base‐stabilisierten monomeren Stammverbindung des Stibanylborans, “H2Sb‐BH2”. Über eine Salzmetathese wurden die silylsubstituierten Verbindungen (Me3Si)2Sb‐BH2⋅LB (LB=NMe3, NHCMe) synthetisiert, die Derivate mit einer Sb‐B‐σ‐Bindung repräsentieren. Unter sehr milden Bedingungen konnten sie in die Zielverbindungen Me3N⋅H2B‐HSb‐BH2⋅NMe3 bzw. H2Sb‐BH2⋅NHCMe überführt werden. Die Produkte wurden durch Röntgenstrukturanalyse, NMR‐Spektroskopie, IR‐Spektroskopie und Massenspektrometrie charakterisiert. Dichtefunktionalrechnungen geben weitere Einblicke in die Stabilität und die Bindungsverhältnisse dieser einzigartigen Verbindungen.
Label‐Free Imaging of Dynamic and Transient Calcium Signaling in Single Cells
Authors: Lu Jin , Li Jinghong
Published: September 2015

Cell signaling consists of diverse events that occur at various temporal and spatial scales, ranging from milliseconds to hours and from single biomolecules to cell populations. The pathway complexities require the development of new techniques that detect the overall signaling activities and are not limited to quantifying a single event. A plasmonic‐based electrochemical impedance microscope (P‐EIM) that can provide such data with excellent temporal and spatial resolution and does not require the addition of any labels for detection has now been developed. The highly dynamic and transient calcium signaling activities at the early stage of G‐protein‐coupled receptor (GPCR) stimulation were thus studied. It could be shown that a subpopulation of cells is more responsive towards agonist stimulation, and the heterogeneity of the local distributions and the transient activities of the ion channels during agonist‐activated calcium flux in single HeLa cells were investigated.
A Hot‐Segment‐Based Approach for the Design of Cross‐Amyloid Interaction Surface Mimics as Inhibitors of Amyloid Self‐Assembly
Authors: Andreetto Erika , Malideli Eleni , Yan Li‐Mei , Kracklauer Michael , Farbiarz Karine , Tatarek‐Nossol Marianna , Rammes Gerhard , Prade Elke , Neumüller Tatjana , Caporale Andrea , Spanopoulou Anna , Bakou Maria , Reif Bernd , Kapurniotu Aphrodite
Published: September 2015

The design of inhibitors of protein–protein interactions mediating amyloid self‐assembly is a major challenge mainly due to the dynamic nature of the involved structures and interfaces. Interactions of amyloidogenic polypeptides with other proteins are important modulators of self‐assembly. Here we present a hot‐segment‐linking approach to design a series of mimics of the IAPP cross‐amyloid interaction surface with Aβ (ISMs) as nanomolar inhibitors of amyloidogenesis and cytotoxicity of Aβ, IAPP, or both polypeptides. The nature of the linker determines ISM structure and inhibitory function including both potency and target selectivity. Importantly, ISMs effectively suppress both self‐ and cross‐seeded IAPP self‐assembly. Our results provide a novel class of highly potent peptide leads for targeting protein aggregation in Alzheimer’s disease, type 2 diabetes, or both diseases and a chemical approach to inhibit amyloid self‐assembly and pathogenic interactions of other proteins as well.
Isolation and Characterization of Lewis Base Stabilized Monomeric Parent Stibanylboranes
Authors: Marquardt Christian , Hegen Oliver , Hautmann Matthias , Balázs Gábor , Bodensteiner Michael , Virovets Alexander V. , Timoshkin Alexey Y. , Scheer Manfred
Published: September 2015

The synthesis of the Lewis base stabilized monomeric parent compound of stibanylboranes, “H2SbBH2”, is reported. Through a salt metathesis route, the silyl‐substituted compounds (Me3Si)2SbBH2⋅LB (LB=NMe3, NHCMe) were synthesized as representatives of derivatives with a SbB σ bond. Under very mild conditions, they could be transformed into the target compounds Me3N⋅H2BHSbBH2⋅NMe3 and H2SbBH2⋅NHCMe, respectively. The products were characterized by X‐ray structure analysis, NMR spectroscopy, IR spectroscopy, and mass spectrometry. DFT calculations give further insight into the stability and bonding of these unique compounds.
Easy and General Synthesis of Large‐Sized Mesoporous Rare‐Earth Oxide Thin Films by ′Micelle Assembly′
Authors: Li Yunqi , Bastakoti Bishnu Prasad , Imura Masataka , Dai Pengcheng , Yamauchi Yusuke
Published: September 2015

Large‐sized (ca. 40 nm) mesoporous Er2O3 thin films are synthesized by using a triblock copolymer poly(styrene‐b‐2‐vinyl pyridine‐b‐ethylene oxide) (PS‐b‐P2VP‐b‐PEO) as a pore directing agent. Each block makes different contributions and the molar ratio of PVP/Er3+ is crucial to guide the resultant mesoporous structure. An easy and general method is proposed and used to prepare a series of mesoporous rare‐earth oxide (Sm2O3, Dy2O3, Tb2O3, Ho2O3, Yb2O3, and Lu2O3) thin films with potential uses in electronics and optical devices.
Flow “Fine” Synthesis: High Yielding and Selective Organic Synthesis by Flow Methods
Authors: Kobayashi Shū
Published: September 2015

The concept of flow “fine” synthesis, that is, high yielding and selective organic synthesis by flow methods, is described. Some examples of flow “fine” synthesis of natural products and APIs are discussed. Flow methods have several advantages over batch methods in terms of environmental compatibility, efficiency, and safety. However, synthesis by flow methods is more difficult than synthesis by batch methods. Indeed, it has been considered that synthesis by flow methods can be applicable for the production of simple gasses but that it is difficult to apply to the synthesis of complex molecules such as natural products and APIs. Therefore, organic synthesis of such complex molecules has been conducted by batch methods. On the other hand, syntheses and reactions that attain high yields and high selectivities by flow methods are increasingly reported. Flow methods are leading candidates for the next generation of manufacturing methods that can mitigate environmental concerns toward sustainable society.
Welfare maximization for bus transit systems with timed transfers and financial constraints
Authors: Chen Linxi , Schonfeld Paul , Miller‐Hooks Elise
Published: September 2015

Conventional and flexible bus services may be combined to better serve regions with a wide range of characteristics. If demand densities and resulting service frequencies are low, the coordination of bus arrivals at transfer stations may significantly reduce passenger transfer times. A method is proposed for integrating, coordinating, and optimizing bus services while considering many‐to‐many travel patterns, demand elasticity, financial constraints, and appropriate service type for various regions. The objective is to maximize welfare, that is, the sum of producer and consumer surplus. The problem is solved with a hybrid optimization method, in which a genetic algorithm with bounded integer variables is selected for solving one of the subproblems. The service types, fares, headways, and service zone sizes are jointly optimized. Sensitivity analyses explore how the choice among conventional and flexible busses depends on the demand, subsidy, and demand elasticity parameters. The results also show that welfare can increase due to coordination, and these increases are found to be higher in cases with high demand or low subsidy. Copyright © 2015 John Wiley & Sons, Ltd.
The effect of surfactant on fermentation of kitasamycin in Streptomyces kitasatoensis
Authors: Zheng Qianli , Gao Shuhong
Published: September 2015

Soybean oil is an important carbon source in kitasamycin fermentation by Streptomyces kitasatoensis. In this study, three different surfactants, Tween 80, Tween 85, and sodium dodecyl sulfate (SDS), were added in the fermentation medium to improve soybean oil utilization. Results indicated that all of these surfactants promote kitasamycin biosynthesis. When 0.5 g/L SDS was added at the beginning of fermentation, kitasamycin production increased by 55% and A5 content improved by 12%, compared with the control treatment (i.e., no surfactant added). Oil consumption rate and lipase activity were also improved in the presence of SDS, producing more organic acids benefiting kitasamycin biosynthesis. High butyric acid concentration in the fermentation medium containing SDS repressed C‐3 acetylation and promoted A5 component accumulation. Additionally, utilization of oil components by S. kitasatoensis was altered. Specifically, linoleic acid was primarily used in the fermentation process with SDS, whereas oleic acid was primarily used in the fermentation process where no surfactant had been added.
Common variants in the ARC gene are not associated with cognitive abilities
Authors: Myrum Craig , Giddaluru Sudheer , Jacobsen Kaya , Espeseth Thomas , Nyberg Lars , Lundervold Astri J. , Haavik Jan , Nilsson Lars‐Göran , Reinvang Ivar , Steen Vidar M. , Johansson Stefan , Wibrand Karin , Le Hellard Stephanie , Bramham Clive R.
Published: September 2015

Introduction

The Activity‐Regulated Cytoskeleton‐associated (ARC) gene encodes a protein that is critical for the consolidation of synaptic plasticity and long‐term memory formation. Given ARC's key role in synaptic plasticity, we hypothesized that genetic variations in ARC may contribute to interindividual variability in human cognitive abilities or to attention‐deficit hyperactivity disorder (ADHD) susceptibility, where cognitive impairment often accompanies the disorder.

Methods

We tested whether ARC variants are associated with six measures of cognitive functioning in 670 healthy subjects in the Norwegian Cognitive NeuroGenetics (NCNG) by extracting data from its Genome‐Wide Association Study (GWAS). In addition, the Swedish Betula sample of 1800 healthy subjects who underwent similar cognitive testing was also tested for association with 19 tag SNPs.

Results

No ARC variants show association at the study‐wide level, but several markers show a trend toward association with human cognitive functions. We also tested for association between ARC SNPs and ADHD in a Norwegian sample of cases and controls, but found no significant associations.

Conclusion

This study suggests that common genetic variants located in ARC do not account for variance in human cognitive abilities, though small effects cannot be ruled out.
IRE1α and TRB3 do not contribute to the disruption of proximal insulin signaling caused by palmitate in C2C12 myotubes
Authors: Pierre Nicolas , Fernández‐Verdejo Rodrigo , Regnier Pauline , Vanmechelen Simon , Demeulder Bénédicte , Francaux Marc
Published: September 2015

Endoplasmic reticulum (ER) stress is a central actor in the physiopathology of insulin resistance (IR) in various tissues. The subsequent unfolded protein response (UPR) interacts with insulin signaling through inositol‐requiring 1α (IRE1α) activation and tribbles homolog 3 (TRB3) expressions. IRE1α impairs insulin actions through the activation of c‐Jun N‐terminal kinase (JNK), and TRB3 is a pseudokinase inhibiting Akt. In muscle cells, the link between ER stress and IR has only been demonstrated by using chemical ER stress inducers or overexpression techniques. However, the involvement of ER stress in lipid‐induced muscle IR remains controversial. The aim of the study is to test whether palmitate‐induced IRE1α signaling and TRB3 expression disturb insulin signaling in myogenic cells. C2C12 myotubes were exposed to palmitate and then stimulated with insulin. siRNA transfection was used to downregulate TRB3 and IRE1α. Palmitate increased TRB3 expression, activated IRE1α signaling, and reduced the insulin‐dependent Akt phosphorylation. Knocking down TRB3 or IRE1α did not prevent the inhibitory effect of palmitate on Akt phosphorylation. Our results support the idea that ER stress is not responsible for lipid‐induced IR in C2C12 myotubes.
Combination of Glycosyltransferases and a Glycosynthase in Sequential and One‐Pot Reactions for the Synthesis of Type 1 and Type 2 N‐Acetyllactosamine Oligomers
Authors: Henze Manja , Schmidtke Simon , Hoffmann Natalie , Steffens Hanna , Pietruszka Jörg , Elling Lothar
Published: September 2015

The disaccharide units of N‐acetyllactosamine (LacNAc) types 1 and 2 and poly‐LacNAc are involved in many biological recognition events. We report the modular design of type 1 (3Galβ1‐3GlcNAcβ1‐; Gal=d‐galactose, GlcNAc=N‐acetyl d‐glucosamine) and type 2 (3Galβ1‐4GlcNAcβ1‐) LacNAc oligomers by combination of two recombinant glycosyltransferases, β1,3‐N‐acetylglucosaminyltransferase from Helicobacter pylori and human β1,4‐galactosyltransferase‐1, with galactosynthase His6BgaC/Glu233Gly from Bacillus circulans. Combination of His6BgaC/Glu233Gly and β1,3‐N‐acetylglucosaminyltransferase in sequential or one‐pot mode results in LacNAc type 1 oligomers with up to four LacNAc units. Moreover, sequential use of all three enzymes gives access to a variety of neo‐LacNAc oligomers. We present oligomers composed of alternating type 1 and 2 units and type 1‐terminated LacNAc type 2 oligomers. These glycan structures are valuable compounds for testing carbohydrate–protein interactions.
A Series of Aluminoborates Templated or Supported by Zinc–Amine Complexes
Authors: Liu Yuan , Pan Rui , Cheng Jian‐Wen , He Huan , Yang Bai‐Feng , Zhang Qiang , Yang Guo‐Yu
Published: September 2015

A series of open‐framework aluminoborates (ABOs), namely, [Zn2(en)5][Al2B10O20] (1), [Zn(en)(dien)][AlB5O10] (2), [Zn(en)3][AlB7O12 (OH)2] (3), [Zn(en)2][AlB5O10] (4), K7{AlO0.5[BO2(OH)]Zn@[B12O21(OH)3]}⋅H2O (5) (en=ethylenediamine, dien=diethylenetriamine) have been made under mild solvothermal conditions and characterized by single‐crystal X‐ray diffraction, powder X‐ray diffraction, elemental analysis, IR and UV/Vis spectroscopy, thermogravimetric analysis, and nonlinear optical determination. They were classified as two types: Compounds 1–4 contain intersecting channels and exhibit various 4‐connected nets built by AlO4 tetrahedra and oxo boron clusters, zinc–amine complexes act as the templates (1–3) or directly bond to the walls of the ABO (4); compound 5 exhibits a double‐layer structure made by nanosized [BO2(OH)]Zn@[B12O21(OH)3] ({BZn@B12}) clusters with Al2O7 dimers, the channels are within the layer. The second harmonic generation (SHG) measurement shows that the SHG responses of 1–3 are about 2.5, 1.6, and 0.5 times that of KH2PO4. Compounds 1–2 are type I phase‐matchable materials. UV/Vis spectroscopy indicates that compounds 1–5 are wide‐band‐gap semiconductors.
Isoenergetic Polymorphism: The Puzzle of Tolazamide as a Case Study
Authors: Boldyreva Elena V. , Arkhipov Sergey G. , Drebushchak Tatiana N. , Drebushchak Valeri A. , Losev Evgeniy A. , Matvienko Alexander A. , Minkov Vasily S. , Rychkov Denis A. , Seryotkin Yurii V. , Stare Jernej , Zakharov Boris A.
Published: September 2015

In the present case study of tolazamide we illustrate how many seemingly contradictory results that have been obtained from experimental observations and theoretical calculations can finally start forming a consistent picture: a “puzzle put together”. For many years, tolazamide was considered to have no polymorphs. This made this drug substance unique among the large family of sulfonylureas, which was known to be significantly more prone to polymorphism than many other organic compounds. The present work employs a broad and in‐depth analysis that includes the use of optical microscopy, single‐crystal and powder X‐ray diffraction, IR and Raman spectroscopies, DSC, semiempirical PIXEL calculations and DFT of three polymorphs of tolazamide. This case study shows how the polymorphs of a molecular crystal can be overlooked even if discovered serendipitously on one of numerous crystallizations, and how very different molecular packings can be practically isoenergetic but still crystallize quite selectively and transform one into another irreversibly upon heating.