bluuebunny/crossref_metadata_2025 huggingface dataset:
Module 7: Responding to the Reviews
Authors: Stranack Kevin , Frederiksen Niels Erik
Published: March 2018

Responding to the Reviews'

Kevin Stranack (Author) Niels Erik Frederiksen (Editor)
Module 8: Copyediting
Authors: Stranack Kevin , Frederiksen Niels Erik
Published: March 2018

Copyediting

Kevin Stranack (Author) Niels Erik Frederiksen (Editor)
Setting up a Journal in OJS 3
Authors: Frederiksen Niels Erik
Published: March 2018

Link til PKP/OJS's egen videovejledning i opsætning af et tidsskrift i OJS 3.
Les défis de la réflexivité et de la collaboration recherche-pratique : le cas de l’implantation d’une nouvelle offre de services en santé mentale en première ligne
Authors: Descheneaux Julie , Aubé Denise , Beaucage Clément , Côté Rodrigue
Published: March 2018

L’évaluation d’implantation d’une nouvelle offre de services en santé mentale dans un centre de santé et de services sociaux démontre que le processus de changement doit être accompagné de la création d’espaces réflexifs au sein des équipes de travail afin de créer des conditions favorables à l’implantation. La complexité organisationnelle est un enjeu avec lequel il faut composer. Le rôle de la collaboration recherche-pratique dans ce processus d’implantation du changement est souligné afin de mieux comprendre les enjeux de la création d’espaces réflexifs dans une organisation. Alors que les espaces réflexifs prévus dans la planification initiale ne se sont pas concrétisés, l’interaction continue entre la recherche et la pratique a permis d’actualiser sous une forme inattendue les mécanismes réflexifs dans l’organisation en changement grâce aux espaces de collaboration mis en place et aux mécanismes d’application des connaissances portés par la posture épistémologique, la création d’alliances et le fonctionnement par cycle.
La communication au sein de foyers familiaux. Une nouvelle preuve de la pertinence d’une analyse relationnelle
Authors: Jalbert Paul , Laflamme Simon
Published: March 2018

Dans cet article, nous rappelons quelques éléments d’une analyse relationnelle en confrontant son appareil conceptuel à celui qui est à l’oeuvre dans les modélisations qui ont pour centre l’individu. Nous énumérons quelques travaux empiriques qui, entre autres, ont relativisé la pertinence de la catégorie d’intention, catégorie qui est prééminente dans la plupart des études qui se focalisent sur l’individu. Enfin, nous rapportons les résultats d’un nouveau travail empirique qui, dans le prolongement des précédents, met en valeur l’analyse relationnelle. Ce travail repose sur l’observation des échanges qui ont cours au sein de foyers familiaux.
Un petit monde en Ontario. Application d’un modèle relationnel trialectique à la vie d’une communauté canadienne
Authors: Vautier Claude
Published: March 2018

Face aux controverses encore vives entre les tenants du sujet et ceux des structures, entre ceux qui pensent que l’action est au centre de la sociologie et ceux qui sont convaincus que ce sont les systèmes sociétaux qui constituent la source de la dynamique sociale, nous pouvons ouvrir des voies nouvelles.

Dans cet article, je cherche à démontrer qu’il est possible de sortir des approches actionnistes, structuralistes, de même que phénoménologiques, pour comprendre les phénomènes sociétaux. Pour ce faire, j’essaie de réintroduire une catégorie oubliée, l’événement, comme une catégorie importante de la recherche en sociologie. Mais, plus important, je propose un modèle relationnel qui étudie, non les catégories, mais les relations entre les catégories. Il ne le fait pas à la façon des modèles de la théorie des réseaux en étudiant les « relations entre », mais en se concentrant sur le caractère hologrammatique des systèmes sociétaux, c’est-à-dire sur l’idée selon laquelle individu, système et événement sont simplement indissociables les uns des autres.

Le modèle repose sur l’étude des liens qui unissent de façon très intime les catégories en question. Ces liaisons sont telles que chaque catégorie est étudiée dans sa relation avec chacune des deux autres puis dans son rapport au rapport entre les deux autres. L’application empirique réalisée montre que l’on peut ainsi mieux comprendre les chemins ou histoires de vie de membres d’une petite communauté du nord-est de l’Ontario, leurs évolutions, voire leurs bifurcations, dans certains cas, qu’avec des modèles reposant sur les ressorts de l’action ou ceux des structures.
Microbes in deionized and tap water: Implications for maintenance of laboratory water production system
Authors: Ng Wenfa
Published: March 2018

Microbes, with their vast metabolic capabilities and great adaptability, occupy almost every conceivable ecological niche on Earth. Thus, could they survive in oligotrophic deionized (DI) water? Observations of white cauliflower-like lumps and black specks in salt solutions after months of storage in plastic bottles suggested a microbial origin for the “contaminants”. Growth experiments was conducted to profile the microbial diversity of fresh DI water, produced on a just-in-time basis by a filter cum ion exchange system with tap water as feed. Inoculation of DI water on R2A agar and a formulated colourless agar followed by multi-day aerobic incubation revealed the presence of a large variety of microbes with differing pigmentations, growth rates, colony sizes and morphologies. Additionally, greater abundance and diversity of microorganisms was recovered at 30 oC compared to 25 and 37 oC; most probably due to adaptation of microbes to tropical ambient water temperatures of 25 to 30 oC. Comparative experiments with tap water as inoculum recovered a significantly smaller number and diversity of microorganisms; thus, suggesting that monochloramine residual disinfectant in tap water was effective in inhibiting cell viability. In contrast, possible removal of monochloramine by adsorption onto ion exchange resins of the DI water production system might explain the observed greater diversity and abundance of viable microbes in DI water. More importantly, greater diversity and abundance of microbes from tap water were recovered on R2A agar compared to formulated colourless agar, which suggested that chelating compounds in R2A agar could have complexed monochloramine and reduced its toxicity towards microbes. Similar chelating compounds were unlikely to be present in the formulated colourless agar. Finally, keystone species secreting signaling molecules and metabolites could induce the growth of neighbouring cells embedded in the agar matrix. This explained the presence of large clear zones devoid of colonies where there was no keystone species. Additionally, close proximity of colonies on agar suggested that cooperative and neutral relationships guided by exchange of metabolite and signaling molecules might be more prevalent compared to antagonistic relationships in which inhibitory compounds were used. Collectively, this study confirmed the presence of microbes in fresh DI water and tap water. Propensity of microbes in forming biofilm on various surfaces suggested that intermittent flow in just-in-time DI water production provided opportunities for cell attachment and biofilm formation during water stagnation, and subsequent dislodgement and resuspension of cells upon water flow. Thus, regular maintenance and cleaning of the production system should help reduce DI water’s microorganism load.
Slippage of degenerate primers can cause variation in amplicon length
Authors: Elbrecht Vasco , Hebert Paul D.N. , Steinke Dirk
Published: March 2018

Metabarcoding studies often employ degenerate primers to reduce amplification bias and increase the number of detected taxa. However, degeneracy has the disadvantage of lowering binding specificity although the exact mechanisms and potential biases introduced by such off-target amplification are not fully understood. We examined sequences recovered from the ten most abundant operational taxonomic units (OTUs) in two mock communities to investigate the specificity and binding behavior of five degenerate primer sets. Our results indicate that primers frequently bound 1-2 bp upstream in taxa where a homopolymer region was present in the amplification direction. As well, although less frequent, degeneracy occasionally led to primer binding 1 bp downstream. Some widely used primer sets were severely affected by this slippage effect, while others were not. Our study shows that primer slippage can produce taxon-specific length variation in amplicons and subsequent length variation in recovered sequences. While this variation will only have small impacts on OTU designation by clustering algorithms that ignore terminal gaps, primer sets employed in metabarcoding projects should be evaluated for their sensitivity to slippage. Moreover, steps should be taken to reduce slippage by improving protocols for primer design. For example, the flanking region adjacent to the 3' end of the primer is not considered by current primer development software although GC clamps in this position could mitigate slippage. While degeneracy is important to ensure the universality of a primer, binding in homopolymer regions should be avoided.
Cigarette smoke enhances oncogene addiction to c‐MET and desensitizes EGFR‐expressing non‐small cell lung cancer to EGFR TKIs
Authors: Tu Chih‐Yen , Cheng Fang‐Ju , Chen Chuan‐Mu , Wang Shu‐Ling , Hsiao Yu‐Chun , Chen Chia‐Hung , Hsia Te‐Chun , He Yu‐Hao , Wang Bo‐Wei , Hsieh I‐Shan , Yeh Yi‐Lun , Tang Chih‐Hsin , Chen Yun‐Ju , Huang Wei‐Chien
Published: March 2018

Cigarette smoking is one of the leading risks for lung cancer and is associated with the insensitivity of non‐small cell lung cancer (NSCLC) to epidermal growth factor receptor (EGFR) tyrosine kinase inhibitors (TKIs). However, it remains undetermined whether and how cigarette smoke affects the therapeutic efficacy of EGFR TKIs. In this study, our data showed that chronic exposure to cigarette smoke extract (CSE) or tobacco smoke‐derived carcinogen benzo[α]pyrene, B[α]P, but not nicotine‐derived nitrosamine ketone (NNK), reduced the sensitivity of wild‐type EGFR‐expressing NSCLC cells to EGFR TKIs. Treatment with TKIs almost abolished EGFR tyrosine kinase activity but did not show an inhibitory effect on downstream Akt and ERK pathways in B[α]P‐treated NSCLC cells. CSE and B[α]P transcriptionally upregulate c‐MET and activate its downstream Akt pathway, which is not inhibited by EGFR TKIs. Silencing of c‐MET reduces B[α]P‐induced Akt activation. The CSE‐treated NSCLC cells are sensitive to the c‐MET inhibitor crizotinib. These findings suggest that cigarette smoke augments oncogene addiction to c‐MET in NSCLC cells and that MET inhibitors may show clinical benefits for lung cancer patients with a smoking history.
Opportunistic Market‐Driven Regional Shifts of Cropping Practices Reduce Food Production Capacity of China
Authors: Yuan Wenping , Liu Shuguang , Liu Wei , Zhao Shuqing , Dong Wenjie , Tao Fulu , Chen Min , Lin Hui
Published: March 2018

China is facing the challenge of feeding a growing population with the declining cropland and increasing shortage of water resources under the changing climate. This study identified that the opportunistic profit‐driven shifts of planting areas and crop species composition have strongly reduced the food production capacity of China. First, the regional cultivation patterns of major crops in China have substantially shifted during the past five decades. Southeast and South China, the regions with abundant water resources and fewer natural disasters, have lost large planting areas of cropland in order to pursue industry and commerce. Meanwhile, Northeast and Northwest China, the regions with low water resources and frequent natural disasters, have witnessed increases in planting areas. These macroshifts have reduced the national food production by 1.02% per year. The lost grain production would have been enough to feed 13 million people. Second, the spatial shifts have been accompanied by major changes in crop species composition, with substantial increases in planting area and production of maize, due to its low water consumption and high economic returns. Consequently, the stockpile of maize in China has accounted for more than half of global stockpile, and the stock to use ratio of maize in China has exceeded the reliable level. Market‐driven regional shifts of cropping practices have resulted in larger irrigation requirements and aggravated environmental stresses. Our results highlighted the need for Chinese food policies to consider the spatial shifts in cultivation, and the planting crop compositions limited by regional water resources and climate change.
Motions of the Convection Reversal Boundary and Local Plasma in the High‐Latitude Ionosphere
Authors: Chen Yun‐Ju , Heelis Roderick A.
Published: March 2018

We present results from a systematic study of multisatellite samplings from the Defense Meteorological Satellite Program F13, F15, F16, F17, and F18 satellites over the period from 2007 to 2015 that describe the motion of the convection reversal boundary (CRB) and the local plasma flow across it. Focusing on the cases with continuous poleward and equatorward CRB motion sampled by three consecutive satellites within 50 min, 45% of the time the CRB motion may deviate from the local plasma motion near dawn and dusk where the reconnection process is unlikely to be present. Differences in the inferred CRB motion and the local plasma motion may arise from apparent motion induced by the local time displacement of consecutive samples across the CRB that is tilted with respect to a line of constant latitude. The presence of a viscous‐like interaction across the CRB can also contribute to the difference in the CRB and plasma motion. Accounting for these processes, the CRB motion and the motion of the plasma at the CRB are consistent only if a back and forth motion over a timescale of a few minutes is superimposed on a monotonic migration of the CRB over longer time periods.
Strong Sporadic E Occurrence Detected by Ground‐Based GNSS
Authors: Sun Wenjie , Ning Baiqi , Yue Xinan , Li Guozhu , Hu Lianhuan , Chang Shoumin , Lan Jiaping , Zhu Zhengping , Zhao Biqiang , Lin Jian
Published: March 2018

The ionospheric sporadic E (Es) layer has significant impact on radio wave propagation. The traditional techniques employed for Es layer observation, for example, ionosondes, are not dense enough to resolve the morphology and dynamics of Es layer in spatial distribution. The ground‐based Global Navigation Satellite Systems (GNSS) technique is expected to shed light on the understanding of regional strong Es occurrence, owing to the facts that the critical frequency (foEs) of strong Es structure is usually high enough to cause pulse‐like disturbances in GNSS total electron content (TEC), and a large number of GNSS receivers have been deployed all over the world. Based on the Chinese ground‐based GNSS networks, including the Crustal Movement Observation Network of China and the Beidou Ionospheric Observation Network, a large‐scale strong Es event was observed in the middle latitude of China. The strong Es shown as a band‐like structure in the southwest‐northeast direction extended more than 1,000 km. By making a comparative analysis of Es occurrences identified from the simultaneous observations by ionosondes and GNSS TEC receivers over China middle latitude statistically, we found that GNSS TEC can be well employed to observe strong Es occurrence with a threshold value of foEs, 14 MHz.
Shapes of Magnetically Controlled Electron Density Structures in the Dayside Martian Ionosphere
Authors: Diéval C. , Kopf A. J. , Wild J. A.
Published: March 2018

Nonhorizontal localized electron density structures associated with regions of near‐radial crustal magnetic fields are routinely detected via radar oblique echoes on the dayside of Mars with the ionospheric sounding mode of the Mars Advanced Radar for Subsurface and Ionospheric Sounding (MARSIS) radar onboard Mars Express. Previous studies mostly investigated these structures at a fixed plasma frequency and assumed that the larger apparent altitude of the structures compared to the normal surrounding ionosphere implied that they are bulges. However, the signal is subjected to dispersion when it propagates through the plasma, so interpretations based on the apparent altitude should be treated with caution. We go further by investigating the frequency dependence (i.e., the altitude dependence) of the shape of 48 density structure events, using time series of MARSIS electron density profiles corrected for signal dispersion. Four possible simplest shapes are detected in these time series, which can give oblique echoes: bulges, dips, downhill slopes, and uphill slopes. The altitude differences between the density structures and their edges are, in absolute value, larger at low frequency (high altitude) than at high frequency (low altitude), going from a few tens of kilometers to a few kilometers as frequency increases. Bulges dominate in numbers in most of the frequency range. Finally, the geographical extension of the density structures covers a wide range of crustal magnetic fields orientations, with near‐vertical fields toward their center and near‐horizontal fields toward their edges, as expected. Transport processes are suggested to be a key driver for these density structures.
Improved Global Net Surface Heat Flux
Authors: Carton James A. , Chepurin Gennady A. , Chen Ligan , Grodsky Semyon A.
Published: March 2018

Surface heat flux estimates from widely used atmospheric reanalyses differ locally by 10–30 W m−2even in time mean. Here a method is presented to help identify the errors causing these differences and to reduce these errors by exploiting hydrographic observations and the resulting temperature increments produced by an ocean reanalysis. The method is applied to improve the climatological monthly net surface heat fluxes from three atmospheric reanalyses: MERRA‐2, ERA‐Interim, and JRA‐55, during an 8 year test period 2007–2014. The results show that the time mean error, as evaluated by consistency with the ocean heat budget, is reduced to less than ±5 W m−2over much of the subtropical and midlatitude ocean. For the global ocean, after all the corrections have been made, the 8 year mean global net surface heat imbalance has been reduced to 3.4 W m−2. A method is also presented to quantify the uncertainty in the heat flux estimates by repeating the procedure with many different atmospheric reanalyses and then examining the resulting spread in estimates. This reevaluation of net surface flux reveals, among other results, that the Southern Ocean is a source of heat to the atmosphere.
A Distributed Snow‐Evolution Model for Sea‐Ice Applications (SnowModel)
Authors: Liston Glen E. , Polashenski Chris , Rösel Anja , Itkin Polona , King Jennifer , Merkouriadi Ioanna , Haapala Jari
Published: March 2018

Snow‐depth distributions on sea ice have substantial impacts on winter ice growth and summer ice melt. There are two types of wind‐related snow distributions in this environment: snowdrifts that form around ice pressure ridges; and snow dunes and other snow bedforms that form on relatively level, undeformed ice. A snow‐evolution modeling system (SnowModel) was tested against winter snow observations collected during the Norwegian young sea ICE expedition (N‐ICE2015) north of Svalbard, with an emphasis on reproducing these two types of snow distributions. The SnowModel simulation spanned 1 year, summer 2014 through summer 2015, over a 1.5 km by 1.5 km domain, using a 1 m horizontal grid increment and 3 h time step. Existing SnowModel components, created originally for terrestrial applications, performed energy balance, snow property, snowdrift, and data assimilation calculations in response to prescribed meteorological forcings. A new SnowModel component, SnowDunes, was created to simulate snow‐bedform distributions on level, undeformed ice. Model results reproduced observed snowdrift profiles around pressure ridges and snow‐depth distributions over level, undeformed ice, resulting in physically realistic snow heterogeneity and property information. We conclude that the SnowModel toolkit contains the components required to simulate most processes driving the seasonal distribution of snow on sea ice. SnowModel can evolve snow on sea ice over local to pan‐Arctic areas, using grid increments ranging from 1 m to tens of km, and time increments of subhourly to daily.
Paper‐Derived Ferroelectric Ceramics: A Feasibility Study
Authors: Menge Georg , Lorenz Hannes , Fu Zongwen , Eichhorn Franziska , Schader Florian , Webber Kyle G. , Fey Tobias , Greil Peter , Travitzky Nahum
Published: March 2018

Preceramic paper may serve as a preform to manufacture single sheet as well as multilayer porous ferroelectric ceramic products. In this article, the authors discuss the formation, microstructure, and properties of preceramic papers highly loaded with BaTiO3 filler ranging from 70 to 80 vol% and their conversion into ceramic materials. In order to increase the density of the single sheets, post calendering is applied. These sheets are used for the fabrication of multilayer ceramics using warm lamination technique. After binder burnout and sintering up to 1300 °C for 2 h in air, porous paper‐derived multilayer BaTiO3 is obtained. The effect of ceramic filler content and calendering on the residual porosity in sintered samples is studied. Furthermore, the influence of porosity on the microstructure, mechanical, dielectric, and piezoelectric properties of the sintered BaTiO3 ceramics is investigated.
Simultaneous Fabrication and Functionalization of Nanoparticles of 2D Materials with Hybrid Optical Properties
Authors: Ibrahim Khaled H. , Irannejad Mehrdad , Wales Benji , Sanderson Joseph , Yavuz Mustafa , Musselman Kevin P.
Published: March 2018

A general, rapid technique is introduced to simultaneously fabricate and functionalize nanoparticles of 2D materials. A femtosecond laser is used to irradiate flakes of 2D materials in an ethanol‐containing solvent. The highly energetic laser pulses exfoliate and cleave the flakes into nanosheets with diameters of ≈3 nm and simultaneously dissociate the solvent molecules. The dissociated carbon and oxygen atoms bond with the freshly cleaved 2D nanoparticles to satisfy edge sites, resulting in the formation of hybrid 2D nanoparticles that contain graphene‐like carbon domains as well as the host material. The technique is demonstrated for molybdenum disulfide (MoS2), tungsten disulfide (WS2), and boron nitride (BN) flakes. Notably, the hybrid nanoparticles are formed in as little as 20 min without toxic or corrosive chemicals and are multifunctional. Photoluminescence and absorption owing to both the carbon domains and host 2D material (MoS2, WS2, or BN) are observed. This novel hybrid optical behavior makes these materials promising for emerging nanoelectronic and nanophotonic applications.
Highly Efficient Green Light‐Emitting Diodes from All‐Inorganic Perovskite Nanocrystals Enabled by a New Electron Transport Layer
Authors: Liu Baiquan , Wang Lin , Gu Haoshuang , Sun Handong , Demir Hilmi Volkan
Published: March 2018

Adopting proper electron transport layers (ETLs) is essential to high‐performance all‐inorganic perovskite light‐emitting diodes (PeLEDs). However, the effect of ETLs has not been comprehensively investigated in all‐inorganic nanocrystal PeLEDs, while 2,2′,2′′‐(1,3,5‐benzenetriyl) tris‐[1‐phenyl‐1H‐benzimidazole] (TPBi) is the most common ETL. Herein, a novel strategy is proposed to enhance the efficiency of nanocrystal PeLEDs. Tris(8‐hydroxyquinoline) aluminum (Alq3) is incorporated into TPBi to form a new ETL TPBi/Alq3/TPBi, simultaneously enabling charge balance and confinement. The green PeLED with new ETL exhibits a maximum external quantum efficiency (EQE) of 1.43%, current efficiency of 4.69 cd A−1, and power efficiency of 1.84 lm W−1, which are 191%, 192%, and 211% higher than those of PeLEDs with conventional ETL TPBi, respectively. Significantly, the EQE is 36‐fold higher than that of PeLED with high electron mobility ETL. Impressively, the full width at half‐maximum of electroluminescence emission is 16 nm, which is the narrowest among CsPbBr3 PeLEDs. The findings may present a rational strategy to enhance the device engineering of all‐inorganic PeLEDs.
Vertical Organic–Inorganic Hybrid Perovskite Schottky Junction Transistors
Authors: Yu Hyeonggeun , Cheng Yuanhang , Shin Donghun , Tsang Sai‐Wing , So Franky
Published: March 2018

While organolead halide perovskite materials have attracted considerable attention for high efficiency solar cells, they have shown little potential for use in field‐effect transistors (FETs) due to the limited current modulation at room temperature. Here, by developing a vertically gated methylammonium lead iodide (MAPbI3)/indium‐tin oxide (ITO) Schottky junction, a room temperature‐operable vertical MAPbI3 thin‐film transistor is reported. Due to the injection‐controlled gating mechanism as well as the vertical channel structure, a current modulation ratio up to 104 is achieved. Fabrication of a nanoporous ITO source electrode forming a highly rectifying Schottky junction with the MAPbI3 layer is the key for the large current modulation. It is discovered that the electron transporting layers on top of the MAPbI3 layer play an important role in achieving a large current rectification of 107 at the Schottky junction and hence large current on/off ratios of the resulting transistor.
Metal‐Free Cyclization ofortho‐Nitroaryl Ynamides and Ynamines towards Spiropseudoindoxyls
Authors: Marien Niels , Reddy B. Narendraprasad , De Vleeschouwer Freija , Goderis Steven , Van Hecke Kristof , Verniest Guido
Published: March 2018

An efficient metal‐free cascade reaction between 1‐dibromovinyl‐2‐nitro‐substituted arenes and secondary amines results in the formation of polycyclic pseudoindoxyls in a single step. The reaction mechanism leading to these fused ring systems was investigated, and is believed to involve the initial formation of nitroarylated ynamines/ynamides. These intermediates cycloisomerize towards N‐alkenyl‐tethered 2‐aminoisatogens via a carbene intermediate as demonstrated by QTAIM (quantum theory of atoms in molecules) and ELF (electron localization function) analysis. A subsequent intramolecular dipolar cycloaddition afforded the title compounds.
Big (Bio)Chemical Data Mining Using Chemometric Methods: A Need for Chemists
Authors: Parastar Hadi , Tauler Roma
Published: March 2018

This Review summarizes how big (bio)chemical data (BBCD) can be analyzed with multivariate chemometric methods and highlights some of the important challenges faced by modern analytical researches. Here, the potential of chemometric methods to solve BBCD problems that are being encountered in chromatographic, spectroscopic and hyperspectral imaging measurements will be discussed, with an emphasis on their applications to omics sciences. In addition, insights and perspectives on how to address the analysis of BBCD are provided along with a discussion of the procedures necessary to obtain more reliable qualitative and quantitative results. In this Review, the importance of “big data” and of their relevance to (bio)chemistry are first discussed. Thereafter, analytical tools which can produce BBCD are presented as well as the theoretical background of chemometric methods and their limitations when they are applied to BBCD. Finally, the importance of chemometric methods for the analysis of BBCD in different chemical disciplines is highlighted with some examples. In this work, we have tried to cover many of the current applications of big data analysis in the (bio)chemistry field.
A Telomerase‐Responsive DNA Icosahedron for Precise Delivery of Platinum Nanodrugs to Cisplatin‐Resistant Cancer
Authors: Ma Yi , Wang Zhaohui , Ma Yuxuan , Han Zhihao , Zhang Min , Chen Haiyan , Gu Yueqing
Published: March 2018

A telomerase‐responsive DNA icosahedron was designed to precisely release caged platinum nanodrugs into cisplatin‐resistance tumor cells for effective therapy. This DNA icosahedron was constructed from two pyramidal DNA cages connected with telomerase primers and telomeric repeats, and platinum nanodrugs were then encapsulated into the DNA structure. In the presence of telomerase, the primers are extended, leading to inner‐chain substitution of the DNA icosahedron and subsequent release of the caged nanodrugs. This DNA icosahedron can precisely release caged nanodrugs in response to telomerase in tumor cells, giving enhanced anticancer efficacy in drug‐resistant carcinoma and with reduced toxicity to normal tissues. We speculate that this precisely designed, well controlled DNA cage could be generalized to diverse anticancer drugs.
First Year Medical Student Peer Nominations of Professionalism: A Methodological Detective Story about Making Sense of Non‐Sense
Authors: Mullikin Trey C. , Shahi Varun , Grbic Douglas , Pawlina Wojciech , Hafferty Frederic W.
Published: March 2018

This article explores the assessment of professionalism within a cohort of medical students during a sequential 13‐week medical school histology and anatomy course. Across seven data points, students were asked to identify a professionalism role model from amongst their peers and to score Likert‐structured rationales for their decision. Based on density scores, an initial social network analysis identified six peer‐nomination “stars.” However, analysis of these stars revealed considerable variability and random‐like “noise” in both the nomination and explanation data sets. Subsequent analyses of both data sets explored the possibility of underlying patterns in this noise using tests of reliability, principal components factor analysis, and fixed‐effects regression analysis. These explorations revealed the presence of two dimensions (professional vs. supportive) in how students sought to explain their nomination decisions. Although data variability remained quite high, significantly less variability was present in the professional than in the supportive dimension, suggesting that academic helpfulness rationales are both empirically distinct and more mutable than rationales grounded in professionalism‐related factors. In addition, data showed that the greater the stability in one's choice of a professionalism role model nomination over the T1–T7 data periods, the more stable one's reasons for that nomination—both for professionalism and supportive dimensions. Results indicate that while peer assessment of professionalism by first‐year medical students may not be very reliable, students can differentiate between more personal and professional factors, even at this early stage in their professional development. Formal instruction within the pre‐clinical curriculum should recognize and address this distinction. Anat Sci Educ. © 2018 American Association of Anatomists.
Kinetic models for the effect of temperature on flavonoid production in liquid submerged fermentation by Phellinus baumii
Authors: Jiang Fu‐Chun , Zhang He‐Nan , Wu Di , Feng Na , Zhang Zhong , Zhang Jing‐Song , Feng Jie , Yang Yan
Published: March 2018

Kinetic models and temperature control strategy were established to reflect the effect of temperature (22 °C–30 °C) on flavonoid production of Phellinus baumii (P. baumii) in 6‐L fermentor. A modified Logistic equation, Hinshelwood model, and Luedeking Piret equation were used to describe mycelial growth and product formation. The influence of temperature on the estimated kinetic parameters was further studied by regression analysis. Based on kinetic parameters analysis, the new temperature control strategy was proposed. Briefly, at 0–43 H, decreasing temperature (30 °C–28 °C) can shorten the lag phase of mycelial growth, and at 43–90 H, fermentation temperature was reduced gradually from 28 °C to 24 °C to keep high flavonoid productivity. At the fermentation anaphase (90–161 H), temperature was controlled at 24 °C to relieve inhibition of flavonoid and maintain constant production capacity of flavonoid. As a result, the maximum flavonoid yield was reached 4.21 mg/100 mg cell dry weight by temperature control strategy, which was 70.45% higher than that at a constant temperature of 26 °C. Additionally, the establishment of kinetic models based on fermentation temperature, which presented here may provide a scientific basis for further large scales flavonoid production of P. baumii in submerged fermentation.
A Port‐A‐Cath in aorta
Authors: Zoltowska Dominika , Kalavakunta Jagadeesh
Published: March 2018

Key Clinical Message

Totally implantable venous access ports are valuable invention for oncological patients. Erroneous arterial malposition rate is estimated from 1.1% to 3.7% (Bowen et al. Am. J. Surg., 2014, 208, 937). Early recognition and management are crucial to prevent further complications.
A Linear Trinuclear Oxidodiperoxido‐molybdenum(VI) Complex with Single Triazole Bridges: Catalytic Activity in Epoxidation, Alcoholysis, and Acetalization Reactions
Authors: Antunes Margarida M. , Amarante Tatiana R. , Valente Anabela A. , Almeida Paz Filipe A. , Gonçalves Isabel S. , Pillinger Martyn
Published: March 2018

The complex (Htrz)2[Mo3O6(O2)4(trz)2]⋅H2O (1), isolated from the reaction of MoO3 with H2O2 in the presence of 1,2,4‐triazole (trz), displays singular structural features such as double bridges comprising one oxido and one triazole ligand, and peripheral oxidodiperoxido‐molybdenum(VI) units. A comparative study was performed regarding the catalytic activity and stability of complex 1 and the hybrid material [MoO3(trz)0.5] (2) for the epoxidation of cis‐cyclooctene (Cy8), the alcoholysis of epoxides, and the acetalization of benzaldehyde (PhCHO). Methanol or ethanol were used as solvents and reagents for the latter two reactions. For the substrates Cy8, styrene oxide, and PhCHO, the corresponding epoxide, β‐alkoxy alcohol, and dialkyl acetal were obtained with 100 % selectivity at very high conversions. In general, 1 performed better than 2 for the different catalytic reactions. Under certain oxidant/co‐solvent conditions used for Cy8 epoxidation, 1 was converted to 2 during the reaction.
Manganese N‐Heterocyclic Carbene Complexes for Catalytic Reduction of Ketones with Silanes
Authors: Pinto Mara , Friães Sofia , Franco Federico , Lloret‐Fillol Julio , Royo Beatriz
Published: March 2018

Well‐defined manganese(I) carbonyl complexes bearing bis‐N‐heterocyclic carbene (NHC) ligands are shown to be effective catalysts for the reduction of carbonyl groups through hydrosilylation reactions. A wide variety of ketones are selectively reduced to the corresponding alcohols by using phenylsilane, and the cheap and readily abundant polymethylhydrosiloxane (PMHS) in the presence of catalytic amounts of MnI organometallic complexes. Interestingly, α,β‐unsaturated ketones and dialkyl ketones are selectively reduced. Mechanistic studies based on radical scavengers suggest the involvement of radical species in the catalytic reaction.
Towards a Mechanistic Understanding of Factors Controlling the Stereoselectivity of Transketolase
Authors: Baierl Anna , Theorell Axel , Mackfeld Ursula , Marquardt Philipp , Hoffmann Friederike , Moers Stephanie , Nöh Katharina , Buchholz Patrick C. F. , Pleiss Jürgen , Pohl Martina
Published: March 2018

A structural model for thiamine‐diphosphate (ThDP)‐dependent transketolase (TK) was developed to analyse the effect of amino acid exchanges on the stereoselectivity of this synthetically important class of enzymes. In this study the carboligation of 3‐hydroxypyruvate as a donor and propanal, as well as pentanal, was studied. Based on literature data and additional mutagenesis studies using E. coli TK, a four‐state model was developed to explain the stereoselectivity of TKs by the relative orientation of donor and acceptor substrates in the active site prior to C−C‐bond formation. To enable a functional comparison of relevant amino acids of TKs from different species, a standard numbering scheme was developed. Using this concept, H26, H261, and F434 were identified as the key residues which mediate stereoselectivity, where two main factors influenced the arrangement of ThDP‐bound donor and acceptor prior to carboligation: the relative orientation of the substrate side chains and the orientation of the acceptor carbonyl group towards the donor hydroxy group. This model provides a first framework to understand the structure‐function relationships of TKs with respect to their stereoselectivity.
Nucleoside‐Based Self‐Assembling Drugs for Localized Drug Delivery
Authors: Skilling Kathryn J. , Stocks Michael J. , Kellam Barrie , Ashford Marianne , Bradshaw Tracey D. , Burroughs Laurence , Marlow Maria
Published: March 2018

We have synthesized a range of gelators based on the nucleoside analogues gemcitabine and lamivudine, characterizing representative gels from the series using rheology and transmission electron microscopy. Growth inhibition studies of gemcitabine derivatives confirmed the feasibility of these compounds as novel treatments, indicating the potential of nucleoside‐based gelators for localized drug delivery.
Anticancer Gold(III) Peptidomimetics: From Synthesis to in vitro and ex vivo Biological Evaluations
Authors: Boscutti Giulia , Nardon Chiara , Marchiò Luciano , Crisma Marco , Biondi Barbara , Dalzoppo Daniele , Dalla Via Lisa , Formaggio Fernando , Casini Angela , Fregona Dolores
Published: March 2018

Five new AuIII‐peptidodithiocarbamato complexes of the type [AuIIIBr2(dtc‐AA1‐AA2‐OR] (in which AA1=N‐methylglycine (Sar), l/d‐Pro; AA2=l/d‐Ala, α‐aminoisobutyric acid (Aib); R=OtBu, triethylene glycol methyl ether), differing with regard to the amino acid sequence and/or the chiral amino acid configuration, were designed to enhance tumor selectivity and bioavailability. The gold(III)‐based moiety was functionalized to exploit the targeting properties of the peptidomimetic ligand toward two peptide transporters (namely PEPT1 and PEPT2), which are upregulated in several tumor cells. The compounds were synthesized and fully characterized, mainly by means of elemental analysis, one‐ and two‐dimensional NMR spectroscopy, FT‐IR, and UV/Vis spectrophotometry. The crystal structures of three compounds were also solved by X‐ray diffraction. In vitro cytotoxicity studies using a panel of human tumor cell lines (A549 [non‐small‐cell lung carcinoma], MCF‐7 [breast cancer], A2780 [ovarian carcinoma], H1975 [non‐small‐cell lung carcinoma], H460 [large‐cell lung carcinoma], and A431 [human epidermoid carcinoma]) showed the dtc‐Pro‐Aib‐OtBu derivative to be very effective, with GI50 values much lower than those of cisplatin. This complex was thus selected for evaluating stability under physiological conditions and possible interactions with serum albumin, as well in PARP‐1 enzyme inhibition assays and preliminary ex vivo toxicity experiments on healthy rat tissues.
Halogenated Bis(methoxybenzylidene)‐4‐piperidone Curcuminoids with Improved Anticancer Activity
Authors: Schmitt Florian , Subramaniam Dharmalingam , Anant Shrikant , Padhye Subhash , Begemann Gerrit , Schobert Rainer , Biersack Bernhard
Published: March 2018

A series of readily available curcuminoids with a halogenated bis(4‐methoxy/4,5‐dimethoxybenzylidene)‐4‐piperidone structure were prepared and analyzed for their cytotoxic impact on eight human cancer cell lines of five different entities. The known 3,4,5‐trimethoxybenzylidene curcuminoid 2 a and the new bis‐(3‐bromophenyl) and bis‐(3,5‐dibromophenyl) derivatives 3 c and 3 d proved to be more strongly antiproliferative than the known curcuminoid EF24 against six of these cell lines. Compounds 2 a and 3 c caused a distinct increase of reactive oxygen species, which eventually elicited apoptosis in 518A2 melanoma cells. Compound 2 a arrested 518A2 melanoma cells in G1 phase of the cell cycle and had no effect on the expression of pro‐metastatic matrix metalloproteinases MMP‐2 and MMP‐9, whereas 3 c led to an accumulation of 518A2 cells in the G2/M phase and to a downregulation of MMP‐2 expression. In addition, treatment with 2 a and 3 c resulted in significant inhibition of colony formation in HCT116 cells. Both 2 a and 3 c showed antiangiogenic activity, for example, by inhibiting the formation of sub‐intestinal veins (SIV) in zebrafish embryos. Compound 3 c was also well tolerated by mice and inhibited the growth of HCT116 colon cancer xenografts.
Temporal sparse feature auto‐combination deep network for video action recognition
Authors: Wang Qicong , Gong Dingxi , Qi Man , Shen Yehu , Lei Yunqi
Published: March 2018

In order to deal with action recognition for large‐scale video data, we present a spatio‐temporal auto‐combination deep network, which is able to extract deep features from short video segments by making full use of temporal contextual correlation of corresponding pixels among successive video frames. Based on conventional sparse encoding, we further consider the representative features in adjacent nodes of the hidden layers according to activation states similarities. A sparse auto‐combination strategy is applied to multiple input maps in each convolution stage. An information constraint of the representative features of hidden layer nodes is imposed to handle the adaptive sparse encoding of the topology. As a result, the learned features can represent the spatio‐temporal transition relationships better and the number of hidden nodes can be restricted to a certain range. We conduct a series of experiments on two public data sets. The experimental results show that our approach is more effective and robust in video action recognition compared with traditional methods.
Patient Enrichment for Precision‐Based Cancer Clinical Trials: Using Prospective Cohort Surveillance as an Approach to Improve Clinical Trials
Authors: Dalton William S. , Sullivan Daniel , Ecsedy Jeffrey , Caligiuri Michael A.
Published: March 2018

Technological advances have led to the identification of biomarkers and development of novel target‐based therapies. While some novel therapies have improved patient outcomes, the prevalence and diversity of biomarkers and targets in patient populations, especially patients with cancer, has created a challenge for the design and performance of clinical trials. To address this challenge we propose that prospective cohort surveillance of patients may be a solution to promote clinical trial matching for patients in need.
The FDA's Approach to the Prescription Opioid Problem
Authors: Woodcock Janet , Throckmorton Douglas C.
Published: March 2018

Our nation's ongoing prescription opioid abuse crisis, amounting to over 78 billion dollars in health and social costs annually,1 is a critical priority for the US Food and Drug Administration (FDA). As a part of our mission to support the safe and effective use of prescription medicines, the FDA is taking a fresh look at potential scientific and regulatory actions we can take to address this crisis.
Highly Sensitive Luminescence Detection of Photosensitized Singlet Oxygen within Photonic Crystal Fibers
Authors: Williams Gareth O. S. , Euser Tijmen G. , Russell Philip St. J. , MacRobert Alexander J. , Jones Anita C.
Published: March 2018

Highly sensitive, quantitative detection of singlet oxygen (1O2) is required for the evaluation of newly developed photosensitizers and the elucidation of the mechanisms of many processes in which singlet oxygen is known or believed to be involved. The direct detection of 1O2 through its intrinsic phosphorescence at 1270 nm is challenging, because of the extremely low intensity of this emission, coupled with the low quantum efficiency of currently available photodetectors at this wavelength. We introduce hollow‐core photonic crystal fibers (HC‐PCF) as a novel optofluidic modality for photosensitization and detection of 1O2. We report the use of this approach to achieve highly sensitive detection of the luminescence decay of 1O2 produced by using two common photosensitizers, Rose Bengal and Hypericin, within the 60‐μm diameter core of a 15 cm length of HC‐PCF. We demonstrate the feasibility of directly detecting sub‐picomole quantities of 1O2 by using this methodology, and identify some aspects of the HC‐PCF technology that can be improved to yield even higher detection sensitivity.
Broad infectivity of Leidynema appendiculatum (Nematoda: Oxyurida: Thelastomatidae) parasite of the smokybrown cockroach Periplaneta fuliginosa (Blattodea: Blattidae)
Authors: Ozawa Sota , Hasegawa Koichi
Published: March 2018

Host specificity of parasites is important for the understanding of evolutionary strategies of parasitism that would be a basis of predictions of the disease expansion when parasitized hosts invade new environments. The nematode order Oxyurida is an interesting parasite group for studying the evolution of parasitism as it includes parasites of both invertebrates and vertebrates. In our survey, we found that the smokybrown cockroach Periplaneta fuliginosa was primarily infected with only one nematode species Leidynema appendiculatum. In two cases, L. appendiculatum was isolated from two additional cockroach species Pycnoscelus surinamensis, sold in Japan as a reptile food, and Blatta lateralis, captured in the field and cultured in the laboratory. Inoculation of L. appendiculatum into three additional cockroach species P. japonica, Blattella nipponica, and P. surinamensis also resulted in parasitism. Infection prevalence was high, and timing of postembryonic development from hatched nematode larva to mature adult in these hosts was identical with that in P. fuliginosa. While ecological interactions strongly determine the host range, such broad infectivity is still possible in this parasitic nematode.
Origin context of trait data matters for predictions of community performance in a grassland biodiversity experiment
Authors: Roscher Christiane , Schumacher Jens , Gubsch Marlén , Lipowsky Annett , Weigelt Alexandra , Buchmann Nina , Schmid Bernhard , Schulze Ernst‐Detlef
Published: March 2018

Plant functional traits may explain the positive relationship between species richness and ecosystem functioning, but species‐level trait variation in response to growth conditions is often ignored in trait‐based predictions of community performance. In a large grassland biodiversity experiment (Jena Experiment), we measured traits on plants grown as solitary individuals, in monocultures or in mixtures. We calculated two measures of community‐level trait composition, i.e., community‐weighted mean traits (CWM) and trait diversity (Rao's quadratic entropy; FD) based on different contexts in which traits were measured (trait origins). CWM and FD values of the different measurement origins were then compared regarding their power to predict community biomass production and biodiversity effects quantified with the additive partitioning method. Irrespective of trait origin, models combining CWM and FD values as predictors best explained community biomass and biodiversity effects. CWM values based on monoculture, mixture‐mean or community‐specific trait data were similarly powerful predictors, but predictions became worse when trait values originated from solitary‐grown individuals. FD values based on monoculture traits were the best predictors of community biomass and net biodiversity effects, while FD values based on community‐specific traits were the best predictors for complementarity and selection effects. Traits chosen as best CWM predictors were not strongly affected by trait origin but traits chosen as best FD predictors varied strongly dependent on trait origin and altered the predictability of community performance. We conclude that by adjusting their functional traits to species richness and even specific community compositions, plants can change community‐level trait compositions, thereby also changing community biomass production and biodiversity effects. Incorporation of these plastic trait adjustments of plants in trait‐based ecology can improve its predictive power in explaining biodiversity–ecosystem functioning relationships.