bluuebunny/crossref_metadata_2025 huggingface dataset:
Taking the Biographical approach seriously – what does it mean for the concept of biographicity?
Authors: Stauber Barbara
Published: May 2018

The article starts from the dialectic relationship between “the biographicity of the social” and “the sociality of the biographical” – a relationship especially underlined in the works of Bettina Dausien (e.g. 2006). Starting from here, we have not only to look at “what” is reconstructed here, but also “how” this reconstruction is presented . By this, the complex powerful social processes of “addressing” and “being addressed” come into the center of interest (Rose/Ricken, 2018:).
Addressing and the way people let themselves “being addressed” (Althusser) – if and how they let themselves being addressed – this question opens up for processes of subjectivation, as has been conceptualized by Judith Butler and earlier by Michel Foucault: within subjectivation, people undergo a (powerful) process of submission, but within the same process and at the same time they become subjects. It is this paradoxical simultaneity of two movements – submission and becoming a subject – which makes the concept of subjection so fruitful as an analytical tool. The concept of subjection also gives space for the modifications, in which people could (and do) respond – and thus to their agency, and their (maybe subtle) subversion. Judith Butler would frame this with the concept of resignification.
A Julia package for farm-scale soil carbon auditing
Authors: de Gruijter Jaap J , Wheeler Ichsani , Malone Brendan P
Published: May 2018

We introduce Julia package ospats+ for optimal sampling design in the context of farm-scale soil carbon auditing. The main difference with package ospats is that ospats+ maximises the expected profit for the farmer, rather than the statistical criterion of estimation precision. The package is written in Julia for speed of computation. Our methodology has been discussed in general terms by de Gruijter et al. (2016), here we go into the computational aspects. Using a grid of predicted carbon content with associated uncertainty, we optimise a stratified random sampling design: number of strata, stratification of the grid, total sample size and sample sizes within strata. The expected profit is maximised on the basis of sequestered carbon price, sampling costs, and a trading parameter that balances farmer's and buyer's risks due to uncertainty of the estimated amount of sequestered carbon. The core of the methodology is optimisation of the stratification by the Ospats method (de Gruijter et al., 2015), an iterative procedure that re-allocates grid points to strata on the basis of pairwise generalised distances between grid points. The distances are a function of the locations, the predictions and the covariances of the prediction errors. We illustrate the use of ospats+ with an application to an Australian farm.
Gene family innovation, conservation and loss on the animal stem lineage
Authors: Richter Daniel J , Fozouni Parinaz , Eisen Michael B , King Nicole
Published: May 2018

Choanoflagellates, the closest living relatives of animals, can provide unique insights into the changes in gene content that preceded the origin of animals. However, only two choanoflagellate genomes are currently available, providing poor coverage of their diversity. We sequenced transcriptomes of 19 additional choanoflagellate species to produce a comprehensive reconstruction of the gains and losses that shaped the ancestral animal gene repertoire. We identified ~1944 gene families that originated on the animal stem lineage, of which only 39 are conserved across all animals in our study. In addition, ~372 gene families previously thought to be animal-specific, including Notch, Delta, and homologs of the animal Toll-like receptor genes, instead evolved prior to the animal-choanoflagellate divergence. Our findings contribute to an increasingly detailed portrait of the gene families that defined the biology of the Urmetazoan and that may underpin core features of extant animals.
Striatal action-value neurons reconsidered
Authors: Elber-Dorozko Lotem , Loewenstein Yonatan
Published: May 2018

It is generally believed that during economic decisions, striatal neurons represent the values associated with different actions. This hypothesis is based on studies, in which the activity of striatal neurons was measured while the subject was learning to prefer the more rewarding action. Here we show that these publications are subject to at least one of two critical confounds. First, we show that even weak temporal correlations in the neuronal data may result in an erroneous identification of action-value representations. Second, we show that experiments and analyses designed to dissociate action-value representation from the representation of other decision variables cannot do so. We suggest solutions to identifying action-value representation that are not subject to these confounds. Applying one solution to previously identified action-value neurons in the basal ganglia we fail to detect action-value representations. We conclude that the claim that striatal neurons encode action-values must await new experiments and analyses.
Dynein–Dynactin–NuMA clusters generate cortical spindle-pulling forces as a multi-arm ensemble
Authors: Okumura Masako , Natsume Toyoaki , Kanemaki Masato T , Kiyomitsu Tomomi
Published: May 2018

To position the mitotic spindle within the cell, dynamic plus ends of astral microtubules are pulled by membrane-associated cortical force-generating machinery. However, in contrast to the chromosome-bound kinetochore structure, how the diffusion-prone cortical machinery is organized to generate large spindle-pulling forces remains poorly understood. Here, we develop a light-induced reconstitution system in human cells. We find that induced cortical targeting of NuMA, but not dynein, is sufficient for spindle pulling. This spindle-pulling activity requires dynein-dynactin recruitment by NuMA’s N-terminal long arm, dynein-based astral microtubule gliding, and NuMA’s direct microtubule-binding activities. Importantly, we demonstrate that cortical NuMA assembles specialized focal structures that cluster multiple force-generating modules to generate cooperative spindle-pulling forces. This clustering activity of NuMA is required for spindle positioning, but not for spindle-pole focusing. We propose that cortical Dynein-Dynactin-NuMA (DDN) clusters act as the core force-generating machinery that organizes a multi-arm ensemble reminiscent of the kinetochore.
Métodos de controle de plantas daninhas em sistemas orgânicos: breve revisão
Authors: Costa Neumarcio Vilanova , Rodrigues-Costa Andreia Cristina Peres , Coelho Érica Marusa Pergo , Ferreira Sílvio Dougla , Barbosa Jaqueline De Araujo
Published: June 2018

O manejo das plantas daninhas em sistemas orgânicos de produção agrícola representa um grande desafio aos produtores. Para o enfretamento deste desafio torna-se necessário a exploração de práticas de manejo sustentáveis e o desenvolvimento de novas tecnologias. Ressalta-se que existe alternativas tecnológicas ou biológicas que podem ser utilizadas no manejo das plantas daninhas em sistemas orgânicos, e serem empregadas em grandes áreas. Estratégias culturais, biológicos, mecânicos e físicos de manejo podem ser eficientes no controle das plantas daninhas, bem como reduzir o uso de controle químico na agricultura convencional. Desta forma, esta revisão de literatura teve como objetivo o de apresentar métodos alternativos de controle de plantas daninhas e o potencial uso em áreas orgânicas de produção agrícola. Os métodos de controle das plantas daninhas em áreas orgânicas devem abordar sempre estratégias integradas e de forma sustentável.
Experimental methods to evaluate herbicides behavior in soil
Authors: Schreiber Fabio , Scherner Ananda , Andres André , Concenço Germani , Ceolin William Christofari , Martins Matheus Bastos
Published: June 2018

O uso de agrotóxicos na agricultura é praticamente indispensável, contudo, estudos estimam que somente 45% do produto aplicado atinge a cultura, sendo que aproximadamente 30% sofrem deriva, 10% são perdidos por algum processo de transporte (lixiviação, volatilização e escoamento) e 15% atingem o solo. Além disso, do total aplicado, apenas 1% atinge o alvo, ou seja, patógenos, plantas daninhas e insetos. Embora avaliações de riscos de contaminação ambiental de agrotóxicos sejam obrigatórios para o registro e comercialização, frequentemente estudos relatam a presença destes em locais não alvos, sendo os corpos de água os principais prejudicados. Vários processos biológicos, físicos e químicos determinam o destino ambiental e a eficiência desses. Assim, diversos métodos experimentais podem ser utilizados para avaliar o comportamento de agrotóxicos no ambiente. Essa revisão objetiva resumir os métodos mais comumente utilizados para descrever e avaliar os processos nos quais o herbicida está sujeito quando presente no solo, bem como, as vantagens e desvantagens de cada um desses. No geral, em se tratando de destino de agrotóxicos no ambiente, os experimentos em laboratórios fornecem informações mais precisas, pois é possível controlar melhor as condições ambientais e isolar fatores de interesse. Mas é importante salientar que não existe um método mais eficiente, o que existe são métodos que podem fornecer um melhor resultado em determinada situação. Por tanto, a escolha do método vai depender do objetivo do estudo e da estrutura disponível.
In vitro formation of adventitious shoots on caulinary tissue of physiologically contrasting Agave angustifolia plants
Authors: Rodriguez-Ortiz Suzel Rios-Ramirez, , Luna Judith Ruiz- , Velasco Vicente Arturo Velasco-
Published: May 2018

To micropropagate agave plants, somatic tissue is obtained from selected plants that are conditioned for 2 to 6 months to improve their physiological condition and health before in vitro cultivation. The objective of this study was to evaluate the physiological condition of Agave angustifolia plants in terms of its effect on organogenic response in somatic tissue taken from these plants when they are established in similar culture media. In a nursery, growth of four groups of plants was evaluated when they were subjected to different types of irrigation for seven months: 1) water; 2) NS-50% (fertigation with nutrient solution at 50% strength); 3) NS-75%; and 4) NS-100%. At the end of the period, it was found that supplying nutrients is important for plants to achieve better physiological condition. The unfertilized plants and those that received NS-75% had increases of 3.8 and 7.8 leaves, 6.5 and 12.5 cm in length of the largest leaf, and 1610.3 and 4401.4 cm2 in leaf area. Stem tissue was obtained from these stock plants and cultured for 90 days in in vitro culture, and formation of adventitious shoots was assessed. The results showed that the magnitude of organogenesis in stem tissue for formation of adventitious shoots was positively related to the physiological condition of the stock plant. Explants taken from unfertilized stock plants formed 14.6 total shoots and 3.8 shoots on each explant, while those fertigated at 100% concentration of nutrients formed 32.7 total shoots and 8 shoots on each explant.
Effect of ultrasonication on sensory and chemical stability of passion fruit juice during refrigerated storage
Authors: Gomez-Lopez Vicente M. , Amaury Martínez-Yepez Maria E. Buitrago,
Published: May 2018

Passion fruit juice (PFJ) is very susceptible to thermal degradation and may benefit from processing by non-thermal methods such as sonication. This study pursued to test the effect of sonication on sensory quality and related chemical compounds of PFJ during refrigerated storage. Treatment conditions were those of a previous study where a microbiologically stable PFJ was achieved. The effect of ultrasound (20 kHz, 263 W, 89.25 µm) on sensory quality, ºBrix, total titratable acidity (TTA), ºBrix/TTA and reducing and total sugars of PFJ during storage at 4 ºC up to 10 days was studied. Sonication did not cause significant (P>0.05) effects on TTA, ºBrix/TTA and reducing sugars but significantly (P<0.05) increased ºBrix and total sugars content. Panel scored sonication PFJ significantly (P<0.05) lower in colour, flavour and aroma scores; but the global acceptance was similar (P>0.05) than that of non-sonicated juice. Results indicate that sonication of PFJ is a treatment that does not affect the global sensory quality of the product.
Multi-objective optimization of the apple drying and rehydration processes parameters
Authors: Janaszek-Mankowska Radosław Winiczenko,
Published: May 2018

The aim of the paper is to investigate the effect of drying and rehydration parameters on the quality of rehydrated apples and to optimize these parameters based on quality of the rehydrated products. Hybrid artificial neural network (ANN) and multi-objective genetic algorithm (MOGA) method were successfully developed to model, simulate, and optimize the drying and rehydration parameters. This method was applied to the apple tissue, where the simultaneous maximization of the volume ratio (VR) and water absorption capacity (WAC) and the minimization of colour difference (CD) and dry matter loss (DML) were considered. The range of drying and rehydration parameters was: 50-70°C (drying temperature, Td), 0.01-6 m×s-1(drying air velocity, V), and 20-95°C (rehydration temperature, Tr). Additionally, the mathematical formulas for determing the quality parameters of rehydrated apple were developed. The best solution has been found only for: CD, VR, WAC (50.1°C for Td, 0.03 m×s-1 for V, and 67.5°C for Tr). The values of CD, VR, and WAC were predicted as 1.20, 53.2% and 0.57 respectively. It has been observed that DML was always conflicting with other quality parameters.
Impact of production season on the chemical composition and health properties of goat milk and rennet cheese
Authors: Katarzyna Ząbek Stanisław Milewski, , Antoszkiewicz Zofia , Alicja Sobczak Zenon Tański,
Published: May 2018

This study compared selected parameters of milk and rennet cheese produced from milk obtained from alpine goats during winter and summer feeding under climatic conditions of the Warmia and Mazury region. Milk from the winter season contained more protein, less vitamin A and over seven times less vitamin E than milk obtained in summer. In cheese from the winter season, the content of dry matter, fat, protein and vitamin A was lower when compared with cheese from the summer period. The content of total biogenic amines in cheese was almost twice as high in winter than in summer (1056.4 vs 567.6 mg/kg). Winter cheese contained more cadaverines and histamine than summer cheese. The content of tyramine and putrescine was comparable in cheese from both seasons and was higher than the level of histamine. Milk fat from milk obtained in winter contained more long-chained SFA and MUFA in comparison with the summer period. Fat from cheese produced in summer had a higher content of SFA, CLA and ALA, whereas cheese from the period of winter feeding contained more C16:0izo and C18:1. The content of hyper- and hypocholesterolemnic acids was comparable in milk and in cheese with a slightly smaller proportion of hyper-acids and a slightly higher proportion of hypocholesterolemnic acids during summer feeding of goats. In conclusion, it was found that the feeding season had a minor impact on the chemical composition of milk, although it significantly differentiated the chemical composition of rennet cheese produced from that milk and the health quality parameters of both products. Milk from winter feeding had a higher content of protein, whereas the chemical composition of cheese was more beneficial in winter as the content of dry matter, fat and protein was higher. The health properties of both products were more beneficial in summer, which was determined by the profile of fatty acids and the content of vitamin A.
An Assessment of the Influence of Silver Stabilized Hydrogen Peroxide on the Eggshell Condition
Authors: Renata Cegielska-Radziejewska Lukasz Tomczyk, , Lewko Lidia , Konieczny Piotr
Published: May 2018

The aim of the study was to assess the condition of eggshells hygienised with an silver stabilized hydrogen peroxide of different concentrations. Eggs were treated with a solution of the preparation and stored for four weeks. In preliminary investigations the elastic deformation of eggshells was measured and analysed in order to determine the influence of a preparation concentrated at 0.01-3% on the eggshell strength. The research proved that a preparation concentrated at 1-3% significantly reduced the eggshell strength. At the next stage of the research, having excluded the high concentrations with a negative effect on  eggshell strength, i.e. 1-3%, the experiment was conducted again. It was followed by a microbiological analysis in which the total count of aerobic bacteria, yeasts, moulds ad also bacteria from the Pseudomonas genus and Enterobacteriaceae family were measured. The investigations confirmed that the preparation concentrated at 0.01-0.9% did not have a significant influence on eggshell strength. Hygienisation in solutions concentrated at 0.01-0.9% caused complete inactivation of bacteria of the Enterobacteriaceae family, yeasts and moulds. Immediately after treatment with the preparation concentrated at 0.3% the count of aerobic bacteria and the bacteria of the Pseudomonas genus decreased by 1.9 log CFU/g and 0.7 log CFU/g, respectively. The hygienisation of eggs with the preparation concentrated at 0.9% and storing them for four weeks under controlled conditions reduced the count of aerobic bacteria by 1.9 log and the count of Pseudomonas bacteria by 1.7 log, as compared with the reference sample.
Sorption equilibrium and kinetics of thin-layer drying of green bell peppers
Authors: Ramos Ferreira Goncalves Olga R.R. Gandolfi, , Rafael daCosta I. Fontan Renata C. F. Bonomo,
Published: May 2018

Drying is a unit operation widely used in food preservation. It is important to know how this process takes place and the effects of variables such as temperature, relative humidity and air velocity. It is also essential to know the equilibrium moisture content of the product at the temperature under study. Thus, the objective of this study was to determine the sorption isotherms and evaluate the effects of temperature (60°C and 75°C) and air velocity (1.5 m s-1 and 3.0 m s-1) on the thin-layer drying curves of green bell peppers. The experimental sorption data were adjusted to the BET and GAB models, where the latter best described the sorption behavior of the pepper. It was also verified that with the elevation in temperature lower values for the equilibrium moisture content were obtained. The drying data were adjusted to the Page model, Henderson and Pabis model, Newton model and Fick model. From the latter model the effective diffusion coefficient of water in the project was determined, confirming that the increase in temperature did not increase with greater air velocity. The Page model was that which best fit to all drying conditions. The variation in drying air velocity little affected the kinetics of the process, observing only a small reduction in drying time with increased air velocity (approximately 2.4%), while temperature showed the greatest influence, with a large reduction in drying time with increase in this variable (around 41.4%).
Comparing growth and physiological responses of Globba schomburgkii Hook. f. and Globba marantina L. under hydroponic and soil conditions
Authors: Phantong Piyamart , Machikowa Thitiporn , Saensouk Piyaporn , Muangsan Nooduan
Published: May 2018

Globba (Zingiberaceae) are attractive herbaceous plants widely used as ornamental plants. However, cultivation is limited because of low propagation rate and depends on the season only. This research aimed to compare growth and physiological responses of Globba schomburgkii Hook. f. and Globba marantina L. under both soil and hydroponic conditions. In vitro plantlets (8 cm in height) were transplanted to a hydroponic culture with the nutrient film technique (NFT). In soil culture, the plantlets were transplanted to small pots containing sand: burned rice husk: peat moss (1:1:1 by volume). Vegetative growth characteristics were measured at 15, 30, 45 and 60 days after transplanting (DAT), whereas reproductive growth and physiological characteristics were measured at 60 DAT. All there was 100% survival in both growth conditions. Plants of both species grown in hydroponic conditions had higher shoot length, leaf area and stem diameter, except number of shoots than when propagated in soil conditions. Moreover, both species grown in hydroponics had earlier inflorescences and more flowers, indicating that they can be flowering out of season. Additionally, in hydroponic conditions both species had significant higher stomatal conductivity, whereas there were no significant differences in photosynthetic rates, transpiration rates and leaf temperature when compared with soil conditions. Therefore, our study provides evidence that G. schomburgkii and G. marantina are capable of adapting to hydroponic conditions and that hydroponics may be a suitable method for propagating Globba and other ginger plant species into cut flower or potted plants all year round.
ENHANCEMENT OF β-GALACTOSIDASE ACTIVITY OF LACTIC ACID BACTERIA IN FERMENTED CAMEL MILK
Authors: Ibrahim Alaa H.
Published: May 2018

It is known that, the main problem associated with the production of fermented camel milk is the lower growth rate of lactic acid bacteria which caused many quality problems in the final product. The aim of this research was to enhance of β-galactosidase enzymatic activity of Lactobacillus delbrueckii ssp. bulgaricus DSMZ 20081, Streptococcus thermophilus ATCC 19258 and Lactobacillus acidophilus DSMZ 20079 by cell-rupture method to release their intracellular β-galactosidase and used the ruptured cell cultures as the source of the β-galactosidase enzyme. The results show that the bacterial growth rate in fermented camel milk made by using mixed cells of L. delbrueckii ssp. bulgaricus, S. thermophilus and L. acidophilus was 2 h faster than whole cells of the same strains. Moreover, the significant (P<0.05) faster dropping in pH-value to about 4.6 was observed in fermented camel milk made by using mixed cells of S. thermophilus, L. acidophilus and L. delbrueckii ssp. bulgaricus it was 4.65±0.02, 4.64±0.01and 4.63±0.01 during 4 h of fermentation time, respectively. Furthermore, the highest significance (P<0.05) activity of β-galactosidase was obtained during 4 h of fermentation in all fermented camel milk made by using mixed cells of L. delbrueckii ssp. bulgaricus, L. acidophilus and S. thermophilus it was about 1.97±0.12, 1.77±0.06 and 1.70±0.01 IU/ml, respectively. On the other hand, more rapid and efficient utilization of lactose was observed in fermented camel milk made by using mixed cells of S. thermophilus, L. acidophilus and L. delbrueckii ssp. bulgaricus during the first 2 h of incubation time and the higher degree of lactose hydrolysis reached the maximum approximately 37.69, 38.39 and 40.56 % at the end of 10h of incubation time, respectively. The present results revealed that enhance of microbial growth rate in fermented camel milk can be simultaneously achieved by a suitable rupture-cell method.
Physiology of lactation and machine milking in dromedary she-camel
Authors: Kaskous S
Published: May 2018

Dromedary camels have the capability and the genetic potential to achieve high levels of milk production. However, systematic breeding programs to increase milk production are not common in this species. Dromedary camels are not well adapted to machine milking. Milk removal obviously requires in most farms a pre-stimulation through calf suckling before the milking machine can completely harvest the stored milk. In camels, most of the milk is stored in the alveolar compartment (>90-95%) of the udder. Therefore, almost no milk can be obtained in the absence of milk ejection. In addition, the morphological, anatomical and physiological properties of the camel udder are complex and not fully understood. Because of all biological and economical limitations related to machine milking dromedary camels are mostly hand-milked. The introduction of machine milking makes only slow progress and is limited to intensive dairy camel farms in a few countries. Machine milking of dromedary camels showed so far acceptable results. However, some studies clearly showed that udder emptying by machine milking with the available equipment is not satisfactory. The amount of residual milk after machine milking is high and was up to 30 % or even more of the stored milk in some studies. This means that the used machine needs to be improved to fit the camel's udder. Nevertheless, some studies clearly showed that a major proportion of dromedary camels have a suitable machine milking ability.
The effect of date-urea blocks as supplementary feeding on growth of young camels
Authors: Faye Bernard , Ali Almasaud Gaukhar Konuspayeva, , Abdallah Ben Abdallah Ahmed Alafaliq,
Published: May 2018

The objective of the present trial was to evaluate the effect of incorporating date blocks in diet on growth in young camels, and in the same time, to assess the risk of toxicity due to the presence of urea in the blocks. Fifteen 3 years old camels were shared into two groups receiving in addition to alfalfa, respectively 1 kg of commercial concentrate or 1kg of date blocks containing 50% pitted dates. Daily intake was measured, and the animals were weighed, and blood sampled every 2 weeks. No significant impact on total intake and growth throughout the experiment (135 days) was observed, but the assessment of consumption index showed a better efficiency of commercial concentrate (1.89 kg/kg growth) than date block (2.33 kg/kg growth). Uremia was higher in control group receiving the commercial concentrate, but the difference was not significant, except at the 78th day of the experiment. No effect on glycemia, AST and ALT was observed. LDH was significantly higher at the end of the trial, but the values were in normal range. Date blocks could be used safely for a partial substitution of commercial concentrates.
Regulation of alternative mRNA splicing: old players and new perspectives
Authors: Dvinge Heidi
Published: June 2018

Nearly all human multiexon genes are subject to alternative splicing in one or more cell types. The splicing machinery therefore has to select between multiple splice sites in a context‐dependent manner, relying on sequence features in cis‐ and trans‐acting splicing regulators that either promote or repress splice site recognition and spliceosome assembly. However, the functional coupling between multiple gene regulatory layers signifies that splicing can also be modulated by transcriptional or epigenetic characteristics. Other, less obvious, aspects of alternative splicing have come to light in recent years, often involving core components of the spliceosome previously thought to perform a basal rather than a regulatory role in splicing. Together this paints a highly dynamic picture of splicing regulation, where the final splice site choice is governed by the entire transcriptional environment of a gene and its cellular context.
Crystal structure of Campylobacter jejuni peroxide regulator
Authors: Sarvan Sabina , Charih François , Butcher James , Brunzelle Joseph S. , Stintzi Alain , Couture Jean‐François
Published: June 2018

In Campylobacter jejuni (Cj), the metal‐cofactored peroxide response regulator (PerR) transcription factor allows C. jejuni to respond to oxidative stresses. The crystal structure of the metalated form of CjPerR shows that the protein folds as an asymmetric dimer displaying structural differences in the orientation of its DNA‐binding domain. Comparative analysis shows that such asymmetry is a conserved feature among crystallized PerR proteins, and mutational analysis reveals that residues found in the first α‐helix of CjPerR contribute to DNA binding. These studies present the structure of CjPerR protein and highlight structural heterogeneity in the orientation of the metalated PerR DNA‐binding domain which may underlie the ability of PerR to recognize DNA, control gene expression, and contribute to bacterial pathogenesis.
Titania‐Based Spherical Mie Resonators Elaborated by High‐Throughput Aerosol Spray: Single Object Investigation
Authors: Checcucci Simona , Bottein Thomas , Claude Jean‐Benoit , Wood Thomas , Putero Magali , Favre Luc , Gurioli Massimo , Abbarchi Marco , Grosso David
Published: June 2018

In the framework of photonics with all‐dielectric nanoantennas, sub‐micrometric spheres can be exploited for a plethora of applications including vanishing back‐scattering, enhanced directivity of a light emitter, beam steering, and large Purcell factors. Here, the potential of a high‐throughput fabrication method based on aerosol‐spray is shown to form quasi‐perfect sub‐micrometric spheres of polycrystalline TiO2. Spectroscopic investigation of light scattering from individual particles reveals sharp resonances in agreement with Mie theory, neat structural colors, and a high directivity. Owing to the high permittivity and lossless material in use, this method opens the way toward the implementation of isotropic meta‐materials and forward‐directional sources with magnetic responses at visible and near‐UV frequencies, not accessible with conventional Si‐ and Ge‐based Mie resonators.
Defect Chemistry of Oxides for Energy Applications
Authors: Schweke Danielle , Mordehovitz Yuval , Halabi Mahdi , Shelly Lee , Hayun Shmuel
Published: June 2018

Oxides are widely used for energy applications, as solid electrolytes in various solid oxide fuel cell devices or as catalysts (often associated with noble metal particles) for numerous reactions involving oxidation or reduction. Defects are the major factors governing the efficiency of a given oxide for the above applications. In this paper, the common defects in oxide systems and external factors influencing the defect concentration and distribution are presented, with special emphasis on ceria (CeO2) based materials. It is shown that the behavior of a variety of oxide systems with respect to properties relevant for energy applications (conductivity and catalytic activity) can be rationalized by general considerations about the type and concentration of defects in the specific system. A new method based on transmission electron microscopy (TEM), recently reported by the authors for mapping space charge defects and measuring space charge potentials, is shown to be of potential importance for understanding conductivity mechanisms in oxides. The influence of defects on gas‐surface reactions is exemplified on the interaction of CO2 and H2O with ceria, by correlating between the defect distribution in the material and its adsorption capacity or splitting efficiency.
Solution Coating of Small Molecule/Polymer Blends Enabling Ultralow Voltage and High‐Mobility Organic Transistors
Authors: Teixeira da Rocha Cecilia , Haase Katherina , Zheng Yichu , Löffler Markus , Hambsch Mike , Mannsfeld Stefan C. B.
Published: June 2018

Low‐voltage organic field‐effect transistors (OFETs) are of great interest for organic electronics applications that require low power consumption such as wearable electronics, biomedical applications, or mobile electronics. In this work, an approach leading to transistors fabricated from solution with high charge carrier mobilities operating at voltages < 1 V is presented. By blending the small‐molecule semiconductor 6,13‐bis(triisopropylsilyl‐ethynyl)pentacene (TIPS‐pentacene) with polystyrene it is possible to achieve good film coverage and uniformity as well as ultrathin semiconductor films. This reduction in thickness relative to neat films results in a high fraction of the high‐mobility polymorph of TIPS‐pentacene and excellent film morphologies with continuous highly crystalline domains. OFETs using SiO2 as the dielectric with average hole mobilities as high as 8.3 cm2 V−1 s−1 and maximum mobilities of up to 12.3 cm2 V−1 s−1 which favorably compares with the previous record for TIPS‐pentacene, especially when considering the simplicity of the approach, are demonstrated. By depositing the optimized semiconductor blends on solution‐based polymer dielectric layers of polyvinylphenol, cross‐linked with 4,4′‐(hexafluoroisopropylidene)diphthalic anhydride, a record‐high mobility of 4.2 cm2 V−1 s−1 for solution‐processed, ultralow‐voltage OFET devices (operating at <1 V) is obtained.
Porcine small intestine submucosal grafts improve remucosalization and progenitor cell recruitment to sites of upper airway tissue remodeling
Authors: Nayak Jayakar V. , Rathor Aakanksha , Grayson Jessica W. , Bravo Dawn T. , Velasquez Nathalia , Noel Julia , Beswick Daniel M. , Riley Kristen O. , Patel Zara M. , Cho Do‐Yeon , Dodd Robert L. , Thamboo Andrew , Choby Garret W. , Walgama Evan , Harsh Griffith R. , Hwang Peter H. , Clemons Lisa , Lowman Deborah , Richman Joshua S. , Woodworth Bradford A.
Published: June 2018

Background

To better understand upper airway tissue regeneration, the exposed cartilage and bone at donor sites of tissue flaps may serve as in vivo “Petri dishes” for active wound healing. The pedicled nasoseptal flap (NSF) for skull‐base reconstruction creates an exposed donor site within the nasal airway. The objective of this study is to evaluate whether grafting the donor site with a sinonasal repair cover graft is effective in promoting wound healing.

Methods

In this multicenter, prospective trial, subjects were randomized to intervention (graft) or control (no graft) intraoperatively after NSF elevation. Individuals were evaluated at 2, 6, and 12 weeks postintervention with endoscopic recordings. Videos were graded (Likert scale) by 3 otolaryngologists blinded to intervention on remucosalization, crusting, and edema. Scores were analyzed for interrater reliability and cohorts compared. Biopsy and immunohistochemistry at the leading edge of wound healing was performed in select cases.

Results

Twenty‐one patients were randomized to intervention and 26 to control. Subjects receiving the graft had significantly greater overall remucosalization (p = 0.01) than controls over 12 weeks. Although crusting was less in the small intestine submucosa (SIS) group, this was not statistically significant (p = 0.08). There was no overall effect on nasal edema (p = 0.2). Immunohistochemistry demonstrated abundant upper airway basal cell progenitors in 2 intervention samples, suggesting that covering grafts may facilitate tissue proliferation via progenitor cell expansion.

Conclusion

This prospective, randomized, controlled trial indicates that a porcine SIS graft placed on exposed cartilage and bone within the upper airway confers improved remucosalization compared to current practice standards.
Electromagnetic Propagation in a Relativistic Electron Gas at Finite Temperatures
Authors: Reis Daniel M. , Reyes‐Gómez Ernesto , Oliveira Luiz E. , de Carvalho Carlos A. A.
Published: June 2018

The electromagnetic propagation in a relativistic electron gas at finite temperatures and carrier densities is described. Using quantum electrodynamics at finite temperatures, electric and magnetic responses and general constitutive relations are obtained. Rewriting the propagator for the electromagnetic field in terms of the electric and magnetic responses, the modes that propagate in the gas are identified. As expected, the usual collective excitations are obtained, i.e., a longitudinal electric and two transverse magnetic plasmonic modes. In addition, a purely photonic mode is found, which satisfies the wave equation in vacuum, for which the electron gas is transparent. Dispersion relations for the plasmon modes at zero and finite temperatures are presented and the intervals of frequency and wavelength where both electric and magnetic responses are simultaneously negative are identified, a behavior previously thought not to occur in natural systems. The investigation of the electromagnetic responses of a relativistic electron gas shows that, apart from the usual longitudinal electric plasmon mode and the two transverse magnetic plasmon modes, there is also a pure photonic mode that propagates with the speed of light, as if the medium were transparent. Furthermore, there is a region of frequencies and wavenumbers of the external fields where both the longitudinal electric permittivity and magnetic permeability are simultaneously negative, a property found in artificially constructed metamaterials.
Non‐Hermitian Gauged Topological Laser Arrays
Authors: Longhi Stefano
Published: June 2018

Stable and phase‐locked emission in an extended topological supermode of coupled laser arrays, based on concepts of non‐Hermitian and topological photonics, is theoretically suggested. A non‐Hermitian Su–Schrieffer–Heeger chain of coupled microring resonators is considered, and it is shown that application of a synthetic imaginary gauge field via auxiliary passive microrings leads to all supermodes of the chain, except one, to become edge states. The only extended supermode, that retains some topological protection, can stably oscillate suppressing all other non‐topological edge supermodes. Numerical simulations based on a rate equation model of the semiconductor laser arrays confirm stable anti‐phase laser emission in the extended topological supermode and the role of the synthetic gauge field to enhance laser stability.
Ionothermal Synthesis of Triazine–Heptazine‐Based Copolymers with Apparent Quantum Yields of 60 % at 420 nm for Solar Hydrogen Production from “Sea Water”
Authors: Zhang Guigang , Lin Lihua , Li Guosheng , Zhang Yongfan , Savateev Aleksandr , Zafeiratos Spiros , Wang Xinchen , Antonietti Markus
Published: June 2018

Polymeric carbon nitride (PCN), in either triazine or heptazine form, has been regarded as a promising metal‐free, environmentally benign, and sustainable photocatalyst for solar hydrogen production. However, PCN in most cases only exhibits moderate activity owing to its inherent properties, such as rapid charge carrier recombination. Herein we present a triazine–heptazine copolymer synthesized by simple post‐calcination of PCN in eutectic salts, that is, NaCl/KCl, to modulate the polymerization process and optimize the structure. The construction of an internal triazine–heptazine donor–acceptor (D‐A) heterostructure was affirmed to significantly accelerate interface charge transfer (CT) and thus boost the photocatalytic activity (AQY=60 % at 420 nm). This study highlights the construction of intermolecular D‐A copolymers in NaCl/KCl molten salts with higher melting points but in the absence of lithium to modulate the chemical structure and properties of PCN.
Parasitic Behavior of Self‐Replicating Molecules
Authors: Altay Meniz , Altay Yigit , Otto Sijbren
Published: June 2018

Self‐replication plays a central role in the origin of life and in strategies to synthesize life de novo. Studies on self‐replication have focused mostly on isolated systems, while the dynamics of systems containing multiple replicators have received comparatively little attention. Yet most evolutionary scenarios involve the interplay between different replicators. Here we report the emergence of parasitic behavior in a system containing self‐replicators derived from two subtly different building blocks 1 and 2. Replicators from 2 form readily through cross‐catalysis by pre‐existing replicators made from 1. Once formed, the new replicators consume the original replicators to which they owe their existence. These results resemble parasitic and predatory behavior that is normally associated with living systems and show how such lifelike behavior has its roots in relatively simple systems of self‐replicating molecules.
Amidyl Radicals by Oxidation of α‐Amido‐oxy Acids: Transition‐Metal‐Free Amidofluorination of Unactivated Alkenes
Authors: Jiang Heng , Studer Armido
Published: June 2018

A three‐component transition‐metal‐free amidofluorination of unactivated alkenes and styrenes is presented. α‐Amido‐oxy acids are introduced as efficient and easily accessible amidyl radical precursors that are oxidized by a photoexcited organic sensitizer (Mes‐Acr‐Me) to the corresponding carboxyl radical. Sequential CO2 and aldehyde/ketone fragmentation leads to an N‐centered radical that adds to an alkene. Commercial Selectfluor is used to trap the adduct radical through fluorine‐atom transfer. The transformation features by high functional‐group tolerance, broad substrate scope, and practical mild conditions. Mechanistic studies support the radical nature of the cascade.
An Isolable Diphosphene Radical Cation Stabilized by Three‐Center Three‐Electron π‐Bonding with Chromium: End‐On versus Side‐On Coordination
Authors: Wang Wenqing , Xu Cong‐Qiao , Fang Yong , Zhao Yue , Li Jun , Wang Xinping
Published: June 2018

Two salts (2 and 4) containing the radical cations of complexed diphosphenes have been isolated and characterized by electron paramagnetic resonance (EPR) spectroscopy, IR spectroscopy, and single‐crystal X‐ray diffraction. The P−P bond is coordinated to the Cr center either in an end‐on (in 2) or a side‐on (in 4) fashion. The spin density of the radical is delocalized over the Cr atom and the two P atoms in 2 whereas the unpaired electron is mainly localized on the Cr atom in 4. This work provides the first example of a complexed diphosphene radical (2) featuring novel three‐center three‐electron (3c‐3e) π‐bonding in the Cr‐P‐P unit, and the first example of a 17 e Cr radical with a side‐on π‐bonded ligand (4).
Exploiting Synergistic Effects in Organozinc Chemistry for Direct Stereoselective C‐Glycosylation Reactions at Room Temperature
Authors: Hernán‐Gómez Alberto , Orr Samantha A. , Uzelac Marina , Kennedy Alan R. , Barroso Santiago , Jusseau Xavier , Lemaire Sébastien , Farina Vittorio , Hevia Eva
Published: June 2018

Pairing a range of bis(aryl) zinc reagents ZnAr2 with the stronger Lewis acidic [(ZnArF2)] (ArF=C6F5), enables highly stereoselective cross‐coupling between glycosyl bromides and ZnAr2 without the use of a transition metal. Reactions occur at room temperature with excellent levels of stereoselectivity, where ZnArF2 acts as a non‐coupling partner although its presence is crucial for the execution of the C(sp2)–C(sp3) bond formation process. Mechanistic studies have uncovered a unique synergistic partnership between the two zinc reagents, which circumvents the need for transition‐metal catalysis or forcing reaction conditions. Key to the success of the coupling is the avoidance of solvents that act as Lewis bases versus diarylzinc compounds (e.g. THF).
Asymmetric Synthesis of (R)‐1‐Alkyl‐Substituted Tetrahydro‐ß‐carbolines Catalyzed by Strictosidine Synthases
Authors: Pressnitz Desiree , Fischereder Eva‐Maria , Pletz Jakob , Kofler Christina , Hammerer Lucas , Hiebler Katharina , Lechner Horst , Richter Nina , Eger Elisabeth , Kroutil Wolfgang
Published: June 2018

Stereoselective methods for the synthesis of tetrahydro‐ß‐carbolines are of significant interest due to the broad spectrum of biological activity of the target molecules. In the plant kingdom, strictosidine synthases catalyze the C−C coupling through a Pictet–Spengler reaction of tryptamine and secologanin to exclusively form the (S)‐configured tetrahydro‐ß‐carboline (S)‐strictosidine. Investigating the biocatalytic Pictet–Spengler reaction of tryptamine with small‐molecular‐weight aliphatic aldehydes revealed that the strictosidine synthases give unexpectedly access to the (R)‐configured product. Developing an efficient expression method for the enzyme allowed the preparative transformation of various aldehydes, giving the products with up to >98 % ee. With this tool in hand, a chemoenzymatic two‐step synthesis of (R)‐harmicine was achieved, giving (R)‐harmicine in 67 % overall yield in optically pure form.
Turning on Solid‐State Fluorescence with Light
Authors: Schramm Stefan , Karothu Durga Prasad , Raj Gijo , Laptenok Sergey P. , Solntsev Kyril M. , Naumov Panče
Published: June 2018

A bioinspired fluorophore that is analogous to the substrate in the bioluminescence of fireflies was prepared and reacts when exposed to weak blue LED light. Upon excitation, this material is photodecarboxylated with a nearly 81‐fold enhancement of the solid‐state emission, the fluorescence quantum yield of the product in solution is approximately 90 %, and violent disintegrative effects occur as a result of the release of carbon dioxide. Crystallographic and computational results, together with global spectral analysis of the kinetics, confirmed that most of the emission observed in the decay‐associated spectra is intrinsic to the product molecule, with only a minor contribution from an excimer through π–π stacking of the molecules in the crystal.
Catalytic activities of NHC‐PdCl2 species based on functionalized tetradentate imidazolium salt in three types of C‐C coupling reactions
Authors: Liu Qing‐Xiang , Zhao Dong‐Xue , Wu Hao , Zhao Zhi‐Xiang , Lv Shi‐Zhen
Published: June 2018

A functionalized tetradentate imidazolium salt 9,10‐bis{di[2′‐(N‐ethylimidazolium‐1‐yl)ethyl]aminomethyl}anthracene tetrakis(hexafluorophosphate) (1) has been synthesized and characterized. The catalytic activity of the NHC‐PdCl2 species formed by compound 1 and PdCl2 was tested in Suzuki‐Miyaura, Heck‐Mizoroki and Sonogashira reactions. The results showed that this catalytic system was effective for above three types of C‐C coupling reactions.
Production of Fatty‐Acid Methyl Esters Via the In Situ Transesterification of Grain Sorghum Bran and Sorghum Distiller's Dried Grains and Solubles
Authors: Wyatt Victor T. , Jones Kerby , Johnston David B. , Moreau Robert A.
Published: June 2018

The acylglycerols (AG) in sorghum bran and distiller's dried grains and solubles (DDGS) from sorghum postfermentation have been converted to fatty‐acid methyl esters (FAME) using an in situ transesterification method. The reactions were conducted at 25 or 40 °C by incubating 8 g of feedstock, containing 1.3–2.4 mmol AG, in a solution of 2.4 or 4.8 mmol of NaOMe dissolved in 6.4 or 12.8 mL MeOH. The experimental results confirmed that reducing the moisture to approximately 2% (w/w) within the feedstock was necessary for the reaction to proceed. All of the reactions were monitored using high‐performance liquid chromatography and all performed better at 40 °C than at 25 °C. The most successful reactions used a AG:NaOMe:MeOH molar ratio of 1.0:2.0:131.7. Those reactions used 4.8 mmol NaOMe dissolved in 12.8 mL MeOH producing up to 98.3% FAME when sorghum bran was used as the feedstock. When DDGS from sorghum were used as the feedstock, the yield averaged 32.2% under the previously established optimal conditions.
Fabrication of regenerated cellulose nanoparticles/waterborne polyurethane nanocomposites
Authors: Shin Eunjoo , Choi Soonmo , Lee Jaewoong
Published: June 2018

Regenerated cellulose nanoparticles (RCNs) are ideal materials for new biomass polymer composites industries. RCNs and composites of RCNs and water‐borne polyurethane (RCN/WPU) were prepared using a facile and environmentally friendly approach without the use of any harmful chemicals. The morphological, thermal, and mechanical properties of the RCN/WPU nanocomposite were analyzed by scanning electron microscopy (SEM), transmission electron microscopy (TEM), thermogravimetric analysis (TGA), rheometer, wide‐angle X‐ray diffraction, and enzymatic hydrolysis. RCNs exhibited low crystallinity upon regeneration with an NaOH‐based aqueous solution, and were identified by SEM and TEM to consist of the more thermodynamically stable cellulose form. TGA showed that the thermal stability of RCN/WPU nanocomposites was increased by the addition of RCNs. Finally, enzymatic hydrolysis using cellulase indicated that the biodegradability of RCN/WPU nanocomposites was also improved. © 2018 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2018, 135, 46633.