bluuebunny/crossref_metadata_2025 huggingface dataset:
Siroheme Assembly and Insertion into Nitrite and Sulfite Reductase
Authors: Stroupe M. Elizabeth , Warren Martin J.
Published: September 2017

The presence and role of siroheme in sulfite and nitrite reductase is reviewed as is the biogenesis of the iron‐containing prosthetic group. As a modified tetrapyrrole, siroheme is synthesized on the uroporphyrinogen III primogenitor template that forms the architectural basis for all family members of this group of compounds. The transformation of uroporphyrinogen III into siroheme requires three steps, involving
S
‐adenosylmethionine‐dependent methylation, macrocyclic ring oxidation, and ferrochelation. Some organisms orchestrate these reactions through three separate enzymes, but others employ multifunctional enzymes that represent protein fusions of the individual enzymes. The requirements for the insertion of siroheme into its cognate enzyme are discussed although little information is available concerning the assembly of the fully functional holoenzyme.
Mussel‐Inspired Polyesters with Aliphatic Pendant Groups Demonstrate the Importance of Hydrophobicity in Underwater Adhesion
Authors: Xu Ying , Liu Qianhui , Narayanan Amal , Jain Dharamdeep , Dhinojwala Ali , Joy Abraham
Published: September 2017

Recognizing the potential for synthetic adhesives that can function in wet environments, elements of mussel foot proteins such as L‐3,4‐dihydroxyphenylalanine (DOPA) and phosphoserine have been incorporated into synthetic adhesives. Such adhesives have corroborated the advantage of surface active groups like DOPA, but have not yet demonstrated superior performance in wet or underwater environments, without using organic solvents. What has been conspicuously absent from such designs is the effect of hydrophobic components in the performance of underwater adhesives. Herein it is shown that incorporation of hydrophobic groups in low modulus polyester adhesives provides very high lap‐shear strength and resistance to water penetration. In addition to the excellent performance in wet conditions, the designed adhesive can be applied underwater without any solvent, is biodegradable, and is designed from soybean oil, which is a readily available and renewable resource.
2D‐Layered Carbon/TiO2 Hybrids Derived from Ti3C2MXenes for Photocatalytic Hydrogen Evolution under Visible Light Irradiation
Authors: Yuan Wenyu , Cheng Laifei , Zhang Yani , Wu Heng , Lv Shilin , Chai Liying , Guo Xiaohui , Zheng Lianxi
Published: September 2017

TiO2 is a promising photocatalytic material for hydrogen generation. However, the fast recombination of electron–holes restricts the photocatalytic performance of TiO2. Herein, this study demonstrates a 2D‐layered carbon/TiO2 (C/TiO2) architecture via CO2 oxidation of 2D‐Ti3C2, in which the 2D carbon layers provide electron transport channels and improve the hole–electron separation efficiency. Compared to Ti3C2 support, the thickness of derived carbon supports is significantly reduced, which enhances the light intensity arriving at the surface of TiO2. The oxidation parameters are investigated systematically. It is found that high temperature and high CO2 gas flux lead to the formation of crystal TiO2 and the oxidation of carbon layers. The bandgap of 2D‐layered C/TiO2 samples is ranged from 2.83 to 2.89 eV. The 2D‐layered C/TiO2 delivers enhanced photocatalytic activity compared with pure TiO2 catalysts. The optimal photocatalytic hydrogen evolution rate of 2D‐layered C/TiO2 is up to 24.04 µmol h−1, which is about 89 times higher than that of pure TiO2. This research broadens the applications of C/TiO2 hybrids and provides new approach to synthesize novel 2D‐layered materials for photocatalytic applications.
First‐Principles Calculations of Quantum Efficiency for Point Defects in Semiconductors: The Example of Yellow Luminance by GaN: CN+ON and GaN:CN
Authors: Zhang Hai‐Shan , Shi Lin , Yang Xiao‐Bao , Zhao Yu‐Jun , Xu Ke , Wang Lin‐Wang
Published: September 2017

Point defects play an important role in the photoelectrical properties of semiconductor materials, and they can be luminescence centers. However, the relationships among the observed luminescence wavelengths, intensities, and the microscopic processes are in most cases unknown, or depend heavily on parameter fitting. In this work, the light‐emitting quantum efficiencies for point defects using ab initio density functional theory are calculated. The study of radiation recombination for electrons and nonradiation recombination for holes is reported here. The results show that the defect CN transition between “−” and “0” charged levels and the defect CN+ON transition between “0” and “+” charged levels both may be responsible for the yellow luminescence (YL) which is observed in experiment. Moreover, the calculation shows significant thermal quenching of the YL starting at 480 K due to re‐excitation of hole into the valence band from the point defects, which is in relatively good agreement with the experimentally observed value. This work shows that it is possible to use ab initio calculations to understand the microscopic mechanisms and the competitions among different channels for the light emissions caused by defects.
Synthesis of Pyrazine–Thiazole Biheteroaryl Compounds through Base‐Promoted Oxidative Cross‐Dehydrogenative Coupling Reactions
Authors: Shan Yuanyuan , Lai Miao , Li Rui , Wu Zhiyong , Zhao Mingqin
Published: September 2017

An efficient and concise one‐pot protocol for the oxidative cross‐dehydrogenative coupling reaction of pyrazine N‐oxides and 1,3‐azole derivatives has been developed. Commercially available and inexpensive 1,3‐azoles were used as the coupling partners. Various biheteroaryl compounds were obtained in up to 67 % yields. This methodology provides a convinent way to construct the pyrazine–thiazole biheteroaryl moieties. Thermogravimetric analysis indicated that the fracture temperature of one of the biheteroaryl compounds was about 237 °C.
Reforming Australia's Superannuation Tax System and the Age Pension to Improve Work and Savings Incentives
Authors: Ingles David , Stewart Miranda
Published: September 2017

Australia's retirement income system combines private and public provision for old age. Retirees rely on private (but highly regulated) superannuation saving that attracts large tax concessions; a public, means‐tested age pension; home ownership; and other private savings. Despite recent changes intended to make the system fairer and more fiscally sustainable, Australia's retirement income system still lacks coherence, produces inequitable outcomes and creates high effective tax rates on work and saving. This article proposes a more coherent approach to address fairness, reduce the effective tax rates on work and saving and provide adequate earnings replacement rates with greater fiscal sustainability than is delivered in the recent reforms.
Altered task‐related modulation of long‐range connectivity in children with autism
Authors: Pillai Ajay S. , McAuliffe Danielle , Lakshmanan Balaji M. , Mostofsky Stewart H. , Crone Nathan E. , Ewen Joshua B.
Published: September 2017

Functional connectivity differences between children with autism spectrum disorder (ASD) and typically developing children have been described in multiple datasets. However, few studies examine the task‐related changes in connectivity in disorder‐relevant behavioral paradigms. In this paper, we examined the task‐related changes in functional connectivity using EEG and a movement‐based paradigm that has behavioral relevance to ASD. Resting‐state studies motivated our hypothesis that children with ASD would show a decreased magnitude of functional connectivity during the performance of a motor‐control task. Contrary to our initial hypothesis, however, we observed that task‐related modulation of functional connectivity in children with ASD was in the direction opposite to that of TDs. The task‐related connectivity changes were correlated with clinical symptom scores. Our results suggest that children with ASD may have differences in cortical segregation/integration during the performance of a task, and that part of the differences in connectivity modulation may serve as a compensatory mechanism. Autism Res 2018, 11: 245–257. © 2017 International Society for Autism Research, Wiley Periodicals, Inc.

Lay Summary

Decreased connectivity between brain regions is thought to cause the symptoms of autism. Because most of our knowledge comes from data in which children are at rest, we do not know how connectivity changes directly lead to autistic behaviors, such as impaired gestures. When typically developing children produced complex movements, connectivity decreased between brain regions. In children with autism, connectivity increased. It may be that behavior‐related changes in brain connectivity are more important than absolute differences in connectivity in autism.
Randomized clinical trial of laparoscopic ultrasonography before laparoscopic colorectal cancer resection
Authors: Ellebæk S B , Fristrup C W , Hovendal C , Qvist N , Bundgaard L , Salomon S , Støvring J , Mortensen M B
Published: September 2017

Background

Intraoperative ultrasonography during open surgery for colorectal cancer may be useful for the detection of unrecognized liver metastases. Laparoscopic ultrasonography (LUS) for the detection of unrecognized liver metastasis has not been studied in a randomized trial. This RCT tested the hypothesis that LUS would change the TNM stage and treatment strategy.

Methods

Patients with colorectal cancer and no known metastases were randomized (1 : 1) to laparoscopic examination (control or laparoscopy plus LUS) in three Danish centres. Neither participants nor staff were blinded to the group assignment.

Results

Three hundred patients were randomized, 150 in each group. After randomization, 43 patients were excluded, leaving 128 in the control group and 129 in the LUS group. Intraoperative T and N categories were not altered by LUS, but laparoscopy alone identified previously undetected M1 disease in one patient (0·8 per cent) in the control group and three (2·3 per cent) in the LUS group. In the latter group, LUS suggested that an additional six patients (4·7 per cent) had M1 disease with liver (4) or para-aortal lymph node (2) metastases. The change in treatment strategy was greater in the LUS than in the control group (7·8 (95 per cent c.i. 3·8 to 13·8) and 0·8 (0 to 4·2) per cent respectively; P = 0·010), but the suspected M1 disease was benign in half of the patients.

Conclusion

Routine LUS during resection of colorectal cancer is not recommended. Registration number: NCT02079389 (http://www.clinicaltrials.gov).
Synergistic Hepatoprotective and Antioxidant Effect of Artichoke, Fig, Blackberry Herbal Mixture on HepG2 Cells and Their Metabolic Profiling Using NMR Coupled with Chemometrics
Authors: Youssef Fadia S. , Labib Rola M. , Eldahshan Omayma A. , Singab Abdel Nasser B.
Published: September 2017

The edible plants have long been reported to possess a lot of biological activities. Herein, the hepatoprotective and the antioxidant activities of the aqueous infusion of the edible parts of Cynara cardunculus, Ficus carica, and Morus nigra and their herbal mixture (CFM) was investigated in vitro using CCl4 induced damage in HepG2 cells. The highest amelioration was observed via the consumption of CFM at 1 mg/ml showing 47.00% and 37.09% decline in aspartate transaminase and alanine transaminase and 77.32% and 101.02% increase in reduced glutathione and superoxide dismutase comparable to CCl4 treated cells. Metabolic profiling of their aqueous infusions was done using nuclear magnetic resonance spectroscopic experiments coupled with chemometrics particularly hierarchical cluster analysis (HCA) and principal component analysis (PCA). The structural closeness of the various metabolites existing in black berry and the mixture as reflected in the PCA score plot and HCA processed from the 1H‐NMR spectral data could eventually explained the close values in their biological behavior. For fig and artichoke, the existence of different phenolic metabolites that act synergistically could greatly interpret their potent biological behavior. Thus, it can be concluded that a herbal mixture composed of black berry, artichoke, and fig could afford an excellent natural candidate to combat oxidative stress and counteract hepatic toxins owing to its phenolic compounds.
Application of Pulse Radiolysis to Mechanistic Investigations of Catalysis Relevant to Artificial Photosynthesis
Authors: Grills David C. , Polyansky Dmitry E. , Fujita Etsuko
Published: September 2017

Taking inspiration from natural photosystems, the goal of artificial photosynthesis is to harness solar energy to convert abundant materials, such as CO2 and H2O, into solar fuels. Catalysts are required to ensure that the necessary redox half‐reactions proceed in the most energy‐efficient manner. It is therefore critical to gain a detailed mechanistic understanding of these catalytic reactions to develop new and improved catalysts. Many of the key catalytic intermediates are short‐lived transient species, requiring time‐resolved spectroscopic techniques for their observation. The two main methods for rapidly generating such species on the sub‐microsecond timescale are laser flash photolysis and pulse radiolysis. These methods complement one another, and both provide important spectroscopic and kinetic information. However, pulse radiolysis proves to be superior in systems with significant spectroscopic overlap between the photosensitizer and other species present during the reaction. Herein, the pulse radiolysis technique and how it has been applied to mechanistic investigations of halfreactions relevant to artificial photosynthesis are reviewed.
Biodiversity maintenance may be lower under partial niche differentiation than under neutrality
Authors: D'Andrea Rafael , Ostling Annette
Published: September 2017

Niche differentiation is normally regarded as a key promoter of species coexistence in competitive systems. One might therefore expect that relative to neutral assemblages, niche‐differentiated communities should support more species with longer persistence and lower probability of extinction. Here we compare stochastic niche and neutral dynamics in simulated assemblages, and find that when local dynamics combine with immigration from a regional pool, the effect of niches can be more complex. Trait variation that lessens competition between species will not necessarily give all immigrating species their own niche to occupy. Such partial niche differentiation protects certain species from local extinction, but precipitates exclusion of others. Differences in regional abundances and intrinsic growth rates have similar impacts on persistence times as niche differentiation, and therefore blur the distinction between niche and neutral dynamical patterns—although niche dynamics will influence which species persist longer. Ultimately, unless the number of niches available to species is sufficiently high, niches may actually heighten extinction rates and lower species richness and local persistence times. Our results help make sense of recent observations of community dynamics, and point to the dynamical observations needed to discern the influence of niche differentiation.
Asymmetric Synthesis of Lysine Analogues with Reduced Basicity, and their Incorporation into Proteasome Inhibitors
Authors: de Bruin Gerjan , van Rooden Eva J. , Ward David , Wesseling Charlotte , van den Nieuwendijk Adrianus M. C. H. , van Boeckel Constant A. A. , Driessen Christoph , Kisselev Alexei F. , Florea Bogdan I. , van der Stelt Mario , Overkleeft Herman S.
Published: September 2017

Most known β2‐selective proteasome inhibitors suffer from relatively poor cell permeability as the result of a net positive charge caused by the basic moiety at P1. In this paper, we describe the synthesis of oligopeptide vinyl sulfones that contain different amino acids bearing amino groups with reduced basicity at P1 and/or P3. For this, we developed the first enantioselective synthesis of lysine(4‐ene) and lysine(4‐yne). These amino acids, as well as histidine and diaminopropionic‐acid‐glycine, were incorporated at the P1 and/or P3 positions of oligopeptide vinyl sulfones. All inhibitors were found to inhibit β2, but with a loss of potency compared to our most potent and selective β2 inhibitor, LU‐102. These results notwithstanding, our results provide important insights for the future design of β2‐selective proteasome inhibitors.
Electrochemical Interpretation of Propagation of the Change in the Membrane Potential Using the Goldman‐Hodgkin‐Katz Equation
Authors: Shirai O. , Kitazumi Y. , Kano K.
Published: September 2017

Nerve conduction has been frequently explained by the Hodgkin‐Huxley equation based on the flow of K+ and Na+ across the cell membrane. By considering the relation between the membrane potential and the membrane current based on the Goldman‐Hodgkin‐Katz equation, it becomes clear that the conventional analysis using the voltage‐clamp method is not correct and that the hyperpolarization condition is artificially made. Taking into account the channel functions and the electronic properties, we suggested a new propagation mechanism. When the nerve cell is excited by an external stimulus, the ligand‐gated channels at the synapse serve as an electric power source to propagate the change in the membrane potential to the synapse terminal along the axon and the voltage‐gated channels at the axon locally assist the directional propagation along the axon.
Practice‐Based Measures of Elementary Science Teachers' Content Knowledge for Teaching: Initial Item Development and Validity Evidence
Authors: Mikeska Jamie N. , Phelps Geoffrey , Croft Andrew J.
Published: September 2017

This report describes efforts by a group of science teachers, teacher educators, researchers, and content specialists to conceptualize, develop, and pilot practice‐based assessment items designed to measure elementary science teachers' content knowledge for teaching (CKT). The report documents the framework used to specify the content‐specific teaching practices and instructional tools that are critical to the work that elementary science teachers engage in with students, curriculum, and instruction. Drawing on this framework, the report details the development process for practice‐based assessment items designed to measure CKT elementary science in three content areas: (a) structure and properties of matter, (b) ecosystems, and (c) Earth's place in the universe. These practice‐based assessment items address the various content challenges elementary science teachers face in their work and were designed to be used as a foundation for building large‐scale assessments of elementary science teachers' CKT science. This report presents initial validity evidence examining the practice‐based CKT science item characteristics using results from online administrations of these items to 250 upper elementary science teachers. Findings reveal that the majority of these new assessment items capture variability in elementary science teachers' performance and that a large proportion of the items differentiate moderately well, supporting a beginning proof‐of‐concept for the conceptualization and design of these practice‐based CKT elementary science assessment items.
Optimization of extrusion conditions for the production of instant grain amaranth‐based porridge flour
Authors: Akande Olamide A. , Nakimbugwe Dorothy , Mukisa Ivan M.
Published: September 2017

Malnutrition is one of the foremost causes of death among children below 5 years in developing countries. Development of nutrient‐dense food formulations using locally available crops has been proposed as a means to combat this menace. This study optimized the extrusion process for the production of a nutritious amaranth‐based porridge flour. Least cost formulations containing grain amaranth, groundnut, iron‐rich beans, pumpkin, orange‐fleshed sweet potato, carrot, and maize were developed and evaluated by a sensory panel (n = 30) for acceptability using the 9‐point hedonic scale. Extrusion process of the most acceptable porridge flour was optimized by response surface methodology (RSM). Barrel temperature (130–170°C) and feed moisture content (14%–20%) were the independent variables which significantly (p < .05) affected in vitro protein digestibility, vitamin A retention, total polyphenol, phytic content, and iron and zinc extractabilities. Optimization of the extrusion process improved the nutritional quality of the instant flour.
Complete response under sorafenib in patients with hepatocellular carcinoma: Relationship with dermatologic adverse events
Authors: Rimola Jordi , Díaz‐González Álvaro , Darnell Anna , Varela María , Pons Fernando , Hernandez‐Guerra Manuel , Delgado Manuel , Castroagudin Javier , Matilla Ana , Sangro Bruno , Rodriguez de Lope Carlos , Sala Margarita , Gonzalez Carmen , Huertas Carlos , Minguez Beatriz , Ayuso Carmen , Bruix Jordi , Reig María
Published: September 2017

The clinical benefit of sorafenib in patients with hepatocellular carcinoma (HCC) has been undervalued due to the absence of complete responses, even though patients who develop early dermatologic reactions have shown to have a positive outcome. In addition, sorafenib is described as an antiangiogenic drug, but it also acts on immunological cells. Thus, the goal of this study was to assess the complete response rate in a retrospective cohort of HCC patients treated with sorafenib and to describe the profile of the patients who achieve complete response for identifying factors related to this event and their connection with the immunological profile of sorafenib. Ten Spanish centers submitted cases of complete response under sorafenib. The baseline characteristics, development of early dermatologic reactions, and cause of treatment discontinuation were annotated. Radiological images taken before starting sorafenib, at first control, after starting sorafenib, at the time of complete response, and at least 1 month after treatment were centrally reviewed. Of the 1119 patients studied, 20 had been classified as complete responders by the centers, but eight of these patients were excluded after central review. Ten patients had complete disappearance of all tumor sites, and two had just a small residual fibrotic scar. Thus, 12 patients were classified as complete responders (58% HCV, median age 59.7 years, 83.4% Child‐Pugh class A, Eastern Cooperative Oncology Group performance status 0 91.7%, and Barcelona Clinic Liver Cancer stage C 83.3%). The median overall survival and treatment duration were 85.8 and 40.1 months, respectively. All but one patient developed early dermatologic reactions, and seven patients discontinued sorafenib after achieving complete response due to adverse events, patient decision, or liver decompensation. Conclusion: Complete response affects 1% of patients with HCC who are treated with sorafenib. The association of complete response with early dermatologic reactions supports the role of a specific immune/inflammatory patient profile in the improved response to sorafenib. (Hepatology 2018;67:612‐622).
Contradictory effects of mitochondria‐ and non‐mitochondria‐targeted antioxidants on hepatocarcinogenesis by altering DNA repair in mice
Authors: Wang Bibo , Fu Jing , Yu Ting , Xu An , Qin Wenhao , Yang Zhishi , Chen Yao , Wang Hongyang
Published: September 2017

Conflicting effects of antioxidant supplementation on cancer prevention or promotion is of great concern to healthy people and cancer patients. Despite recent studies about antioxidants accelerating the progression of lung cancer and melanoma, antioxidants may still play a role in cancer prevention. Both tumor and antioxidants types influence the actual efficacy. However, little is known about the impact of different types of antioxidants on primary hepatocellular carcinoma (HCC), including non‐mitochondrial‐ and mitochondrial‐targeted antioxidants. Utilizing mouse models of chemical hepatocarcinogenesis, we showed that administration of non‐mitochondria‐targeted antioxidants N‐acetylcysteine (NAC) and the soluble vitamin E analog, Trolox, prevented tumorigenesis, whereas administration of mitochondria‐targeted antioxidants SS‐31 (the mitochondria‐targeted peptide) and Mito‐Q (a derivative of ubiquinone) facilitated tumorigenesis. RNA sequencing revealed that NAC and SS‐31 caused very different changes in the oxidation‐reduction state and DNA damage response. In diethylnitrosamine (DEN)‐treated primary hepatocytes, NAC and Trolox alleviated DNA damage by activating ataxia‐telangiectasia mutated (ATM)/ATM and Rad3‐related (ATR) for DNA repair whereas SS‐31 and Mito‐Q aggravated damage by inactivating them. Interestingly, partial recovery of SS‐31‐scavengened mitochondrial reactive oxygen species (mtROS) could alleviate SS‐31‐aggravated DNA damage. Localization of ATM between mitochondria and nuclei was altered after NAC and SS‐31 treatment. Furthermore, blockage of phospho‐ATR (p‐ATR) led to the recurrence of NAC‐ameliorated DEN HCC. In contrast, reactivation of p‐ATR blocked SS‐31‐promoted DEN HCC. Conclusion: These results demonstrate that the type of antioxidants plays a previously unappreciated role in hepatocarcinogenesis, and provide a mechanistic rationale for exploring the therapeutic use of antioxidants for liver cancer. (Hepatology 2018;67:623‐635).
High‐Mass MALDI‐MS Analysis for the Investigation of Protein Encapsulation within an Engineered Capsid Forming Protein
Authors: Root Katharina , Frey Raphael , Hilvert Donald , Zenobi Renato
Published: September 2017

Chemical cross‐linking combined with MALDI‐MS was applied to structural analysis of a protein nanocontainer. Specifically, an engineered variant of lumazine synthase from Aquifex aeolicus (AaLS‐13) was investigated that self‐assembles into a capsid‐like structure and is known to encapsulate other proteins by Coulombic attraction. Two complementary soft ionization techniques, MALDI‐MS and native ESI‐MS, were utilized to map the subunit stoichiometry of the high molecular weight capsid. In accordance with the previously reported cryo‐electron microscopy structure of this protein container, only pentameric subunits were detected. This study highlights the possibility to map subunit stoichiometry via chemical cross‐linking with glutaraldehyde followed by MALDI‐MS. The same approach was used to study protein‐protein interactions during encapsulation of GFP(+36) by the AaLS‐13 capsid. Heterocomplexes between GFP(+36) and AaLS‐13 multimers were not observed when mixed at maximal loading capacity (AalS‐13 monomer:GFP(+36) 4:1). This is in agreement with the known fast encapsulation of GFP(+36) by the protein capsid, which essentially removes any free GFP(+36) from the solution. Exceeding the maximal loading capacity by addition of excess GFP(+36) results in aggregation.
Screening of glycoside hydrolases and ionic liquids for fibre modification
Authors: Rahikainen Jenni , Anbarasan Sasikala , Wahlström Ronny , Parviainen Arno , King Alistair WT , Puranen Terhi , Kruus Kristiina , Kilpeläinen Ilkka , Turunen Ossi , Suurnäkki Anna
Published: September 2017

BACKGROUND

This study elaborates the possibility to apply combined ionic liquid (IL) and enzyme treatments for pulp fibre modification. The approach involves swelling of fibre surfaces with IL followed by enzymatic modification of the disrupted fibre surface using carbohydrate active enzymes.

RESULTS

The capacity of seven cellulose‐dissolving or cellulose‐swelling ionic liquids to swell pulp fibres was compared. In addition, thirteen cellulases and five xylanases were screened for their IL tolerance, which determines their applicability in combined or sequential IL–enzyme treatments of fibres. Among the studied ionic liquids, 1‐ethyl‐3‐methylimidazolium dimethylphosphate ([EMIM]DMP) and 1,3‐dimethylimidazolium dimethylphosphate ([DMIM]DMP) had the strongest effect on fibre swelling. These solvents were also found to be the least inactivating for the studied enzymes.

CONCLUSION

Enzyme compatibility and cellulose‐dissolving capability are not two conflicting properties of an ionic liquid. © 2017 Society of Chemical Industry
Nitrification is the key process determining N use efficiency in paddy soils
Authors: Wang Jing , Zhao Ying , Zhang Jinbo , Zhao Wei , Müller Christoph , Cai Zucong
Published: September 2017

Nitrogen (N) fertilizer use efficiency (NUE) in flooded paddy fields is relatively low. Many N fertilizer management options have been proposed to enhance NUE and minimize environmental damage. However, few investigations are focusing on the role of the characteristics of soil N transformations in regulating NUE and N losses in paddy fields. In this study, we test the role of soil N transformations on NUE and N losses under rice growth conditions in two paddy soils collected from Jiangxi (JX) and Sichuan (SC) in China. The N recoveries of applied15N either as nitrate or ammonium in plant and soil, and N losses estimated by15N balance were investigated in rice pot experiments using a15N tracing technique. The results showed that gross nitrification rates in soil collected from JX were much lower than those in soils collected from SC either at 60% water holding capacity (WHC) or rice growth (flooding) conditions, which could be due to the difference in soil pH. The‐N concentration in soil solution was maintained at a relatively high level for a long time period after N fertilizer application in the JX soil (41 d) compared to the SC soil (26 d), caused by different nitrification rates owing to different soil pH. The15N uptake by rice in the JX soil (29–78%) was always significantly higher than that in the SC soil (22–54%), while N losses from the plant–soil system in the JX soil (17–21%) were always significantly lower than those from the SC soil (20–34%) at the same rice growth stage in the labeled15N ammonium treatment. However, there were no significant differences in15N uptake by rice and N losses in appliedtreatment between the two studied soils. These results indicate that nitrification, not denitrification, was the key process determining NUE and N losses in paddy soils. The results of the N application gradient experiment also indicated that higher amounts of N fertilizer should be applied for the same amount of N uptake, however, this caused higher N losses, in soils characterized by high nitrification rate (e.g., the alkaline soil). Results highlighted that soil N transformations in particular nitrification rate provided a very good guideline for an optimized N management.
Phytoplankton defenses: Do Emiliania huxleyi coccoliths protect against microzooplankton predators?
Authors: Strom Suzanne L. , Bright Kelley J. , Fredrickson Kerri A. , Cooney Elizabeth C.
Published: September 2017

The calcium carbonate plates (coccoliths) surrounding most coccolithophorid cells are strikingly reminiscent of armor, and defense against predators has been hypothesized as a selective advantage provided by these mineral structures. Although microzooplankton are the main predators of small phytoplankton such as coccolithophores, few putative phytoplankton defenses have been tested against this group. In this study, predation by the heterotrophic dinoflagellate Amphidinium longum on three calcifying strains of Emiliania huxleyi was compared with predation on cells acid‐treated to remove coccoliths. As a control for acidification effects on other cell properties, we also compared predation on acid‐treated and untreated non‐calcifying (haploid) E. huxleyi strains. We found no systematic support for the defense hypothesis in this predator‐prey system. Acid‐treated cells experienced predation rates that were higher, the same as, and lower than rates on untreated cells, depending on E. huxleyi strain. Other cell properties showing no relationship to predation included size, dimethylsulfoniopropionate (DMSP) content, and DMSP release. For untreated cells, however, hydrogen peroxide (H2O2) concentration in the cell suspension was positively related to predation, suggesting that H2O2 acts as a signal promoting prey detection, or that H2O2 co‐varies with other (unmeasured) predation‐enhancing cell properties. A. longum uses two different prey capture and ingestion strategies, depending on prey type. This plasticity suggests co‐evolution of predation and defense strategies, facilitating a generalist feeding strategy compatible with the diversity of potential phytoplankton prey.
Design of a Novel Two‐Component Hybrid Dermal Scaffold for the Treatment of Pressure Sores
Authors: Sharma Vaibhav , Kohli Nupur , Moulding Dale , Afolabi Halimat , Hook Lilian , Mason Chris , García‐Gareta Elena
Published: September 2017

The aim of this study is to design a novel two‐component hybrid scaffold using the fibrin/alginate porous hydrogel Smart Matrix combined to a backing layer of plasma polymerized polydimethylsiloxane (Sil) membrane to make the fibrin‐based dermal scaffold more robust for the treatment of the clinically challenging pressure sores. A design criteria are established, according to which the Sil membranes are punched to avoid collection of fluid underneath. Manual peel test shows that native silicone does not attach to the fibrin/alginate component while the plasma polymerized silicone membranes are firmly bound to fibrin/alginate. Structural characterization shows that the fibrin/alginate matrix is intact after the addition of the Sil membrane. By adding a Sil membrane to the original fibrin/alginate scaffold, the resulting two‐component scaffolds have a significantly higher shear or storage modulusG′. In vitro cell studies show that dermal fibroblasts remain viable, proliferate, and infiltrate the two‐component hybrid scaffolds during the culture period. These results show that the design of a novel two‐component hybrid dermal scaffold is successful according to the proposed design criteria. To the best of the authors' knowledge, this is the first study that reports the combination of a fibrin‐based scaffold with a plasma‐polymerized silicone membrane.
Highly Luminescent CB[7]‐Based Conjugated Polyrotaxanes Embedded into Crystalline Matrices
Authors: Erdem Talha , Idris Muazzam , Demir Hilmi Volkan , Tuncel Dönüs
Published: September 2017

π‐Conjugated polymers suffer from low quantum yields (QYs) due to chain–chain interactions. Furthermore, their emission in solid films is significantly quenched due to aggregation leading further decrease in QY. These are the two main issues of these materials hampering their widespread use in optoelectronic devices. To address these issues, here the backbone of poly(9,9′‐bis(6″‐(N,N,N‐trimethylammonium)hexyl)fluorene‐alt‐co‐thiophenelene) is isolated by threading with cucurbit[7]uril (CB7). Subsequently, the conjugated polyrotaxanes are incorporated into organic crystalline matrices to obtain highly efficient color‐converting solids suitable for solid‐state lighting. Upon threading the polymer backbone with CB7s, although the QY of the resulting polyrotaxane in solution state increases, the quenching problem in their solid state is not completely tackled. To solve this problem, these conjugated polyrotaxanes are embedded into various crystalline matrices and their remarkably high QYs (>50%) in the solution are successfully maintained in the solid state. To demonstrate the suitability of these aforementioned materials for solid‐state lighting, a proof‐of‐concept light‐emitting diode is constructed by employing their powders as color converters.
Allelic spectrum of formiminotransferase‐cyclodeaminase gene variants in individuals with formiminoglutamic aciduria
Authors: Majumdar Ramanath , Yori Andrew , Rush Peggy W. , Raymond Kimiyo , Gavrilov Dimitar , Tortorelli Silvia , Matern Dietrich , Rinaldo Piero , Feldman Gerald L. , Oglesbee Devin
Published: September 2017

Background

Elevated plasma and urine formiminoglutamic acid (FIGLU) levels are commonly indicative of formiminoglutamic aciduria (OMIM #229100), a poorly understood autosomal recessive disorder of histidine and folate metabolism, resulting from formiminotransferase‐cyclodeaminase (FTCD) deficiency, a bifunctional enzyme encoded by FTCD.

Methods

In order to further understanding about the molecular alterations that contribute to FIGLU‐uria, we sequenced FTCD in 20 individuals with putative FTCD deficiency and varying laboratory findings, including increased FIGLU excretion.

Results

Individuals tested had biallelic loss‐of‐function variants in protein‐coding regions of FTCD. The FTCD allelic spectrum comprised of 12 distinct variants including 5 missense alterations that replace conserved amino acid residues (c.223A>C, c.266A>G, c.319T>C, c.430G>A, c.514G>T), an in‐frame deletion (c.1373_1375delTGG), with the remaining alterations predicted to affect mRNA processing/stability. These included two frameshift variants (c.990dup, c.1366dup) and four nonsense variants (c.337C>T, c.451A>T, c.763C>T, c.1607T>A).

Conclusion

We observed additional FTCD alleles leading to urinary FIGLU elevations, and thus, providing molecular evidence of FTCD deficiency in cases identified by newborn screening or clinical biochemical genetic laboratory testing.
An analysis of capacities of civil society organizations (CSOs) involved in promotion of community participation in governance in Kenya
Authors: Munene Jane Wamaitha , Thakhathi D. Reckson
Published: September 2017

Although civil society organizations (CSOs) often receive attention in development discourse, they are particularly deemed to provide a new way that ensures good governance. Hence, an understanding of their contributions against the backdrop of governance‐related challenges in Kenya calls for fresh and new research. This article gives attention to CSOs' role in the promotion of community participation in governance. Specifically, it looks into capacities of CSOs involved in these efforts on governance. It links persistent poor governance happening at the counties to inadequate capacities of CSOs involved in the fight against the vice. It argues that CSOs lack vital capacities including adequate funds, staff, offices, and equipment, to be able to sustain action against poor governance. The study methodology involved a survey, focus group discussions, and in‐depth face‐to‐face interviews. A variety of tools were used that included a survey questionnaire, focus group discussion guide, and in‐depth interview guide. Some of the recommendations are that it is important for stakeholders including the government to understand CSOs and provide them with required support. CSOs also need to be given training and exposure to programs in other countries that have successfully addressed governance issues.
Proteomic Analysis of the Secretome of Porcine Alveolar Macrophages Infected with Porcine Reproductive and Respiratory Syndrome Virus
Authors: Li Yuming , Wu Zhuanchang , Liu Ke , Qi Pengfei , Xu Jinpeng , Wei Jianchao , Li Beibei , Shao Donghua , Shi Yuanyuan , Qiu Yafeng , Ma Zhiyong
Published: September 2017

Porcine reproductive and respiratory syndrome virus (PRRSV) causes porcine reproductive and respiratory syndrome (PRRS), which is characterized by reproductive failure and respiratory disorders. The secretome of PRRSV‐infected porcine alveolar macrophages (PAMs), which are the primary target cells of PRRSV, was analyzed by label‐free quantitative proteomics to gain a profile of proteins secreted during PRRSV infection. A total of 95 secreted proteins with differentially expressed levels between PRRSV‐ and mock‐infected PAMs was screened. Among these, the expression levels of 49 and 46 proteins were up‐regulated and down‐regulated, respectively, in PRRSV‐infected cell supernatants, as compared with mock‐infected cell supernatants. Bioinformatic analysis revealed that the differentially expressed proteins were enriched in several signaling pathways related to the immune and inflammatory responses, such as the Toll‐like receptor signaling pathway and NF‐kappa B signaling pathway, and involved in a great diversity of biological processes, such as protein binding and localization, as well as immune effector processes. In addition, PRRSV‐infected cell supernatants induced significant expression of inflammatory cytokines in vascular endothelial cells. These findings suggest that the secreted proteins play potential roles in the host immune and inflammatory responses as well as PRRSV replication, thereby providing new insights into cell‐to‐cell communication during PRRSV infection.
Copper(I)‐Catalyzed Regioselective C‐H Amination of N‐Pyridyl Imines Using Azidotrimethylsilane and TBHP: A One‐Pot, Domino Approach to Substituted Imidazo[4, 5‐b]pyridines
Authors: Nisha  , Bhargava Gaurav , Kumar Yogesh
Published: September 2017

A novel, efficient and one‐pot multicomponent copper‐catalyzed amination of N‐pyridyl imines is described. This, one‐pot, multicomponent reaction, in which imine acts as a directing group by chelating to the metal core, affords a domino approach for the transformation of the commercial pyridinamines, aldehydes and azide into valuable imidazo[4, 5‐b]pyridines with wide substrate extent and diversity.
An Alternative Fragmentation Pathway of 5H‐1,4,2‐Oxathiazoles Under Basic Conditions
Authors: Yong Fui Fong , Hewitt Russell J. , Ong Michelle J. H. , Qiu Guanqi , Burkett Brendan A.
Published: September 2017

Recent advances in the synthesis of 1,4,2‐oxathiazoles have enabled unprecedented structural diversity to be achieved for this class of heterocycles, including 5H‐substituted derivatives. 1,4,2‐oxathiazoles have long been known to undergo fragmentation to afford isothiocyanates and carbonyl‐containing molecules under thermal conditions, yet the behavior of 5H‐1,4,2‐oxathiazoles has yet to be investigated. Based on literature reports, 5H‐1,4,2‐oxathiazoles would be expected to display similar behavior under thermal conditions as their 5,5‐dialkyl/diaryl substituted cousins, but further chemistry of the 5H‐substituent has not been explored. In this preliminary report, the reactivity of 5H‐1,4,2‐oxathiazoles under basic conditions has been investigated, revealing an alternative fragmentation pathway whereby 5H‐1,4,2‐oxathiazoles produce nitriles and the corresponding thioacid salts. Significantly, the base promoted fragmentation pathway is able to be invoked at room temperature, allowing the reaction to proceed without generating any isothiocyanate.
Single‐Phase All‐Solid‐State Lithium‐Ion Battery Using Li3V2(PO4)3 as the Cathode, Anode, and Electrolyte
Authors: Inoishi Atsushi , Omuta Takuya , Yoshioka Yuto , Kobayashi Eiji , Kitajou Ayuko , Okada Shigeto
Published: September 2017

To realize an ideal interface between electrode and electrolyte, a single‐phase all‐solid‐state lithium‐ion battery is studied using Li3V2(PO4)3‐based NASICON‐type material as the cathode, anode, and electrolyte. A dense Li3‐xV2‐xAlx(PO4)3 pellet with the Pt current collectors on both the front and back surfaces successfully demonstrates charge‐discharge reactions based on the V3+/V2+ (anode) and V3+/V4+ (cathode) redox systems at 373 K. Al substitutional doping for V brings the suppression of the electronic conductivity and increase in the ionic conductivity. As a result, Al‐doped material (Li3V1.6Al0.4(PO4)3) exhibites the best charge‐discharge performance in the Li3V2‐xAlx(PO4)3 system (x=0 ‐ 0.6) because of its high ionic conductivity and low electronic conductivity. The concept of a single‐phase battery with a single material offers a new approach to avoid side reactions during cell fabrication of oxide‐based all‐solid‐state lithium‐ion batteries.
Microtubular SnO2/V2O5 Composites Derived from Cellulose Substance as Cathode Materials of Lithium‐ion Batteries
Authors: Li Xue , Ji Yue , Huang Jian‐Sheng , Li Jiao , Huang Jianguo
Published: September 2017

Three‐dimensional microtubular SnO2/V2O5 composites with various SnO2 contents (2.2, 12.1 and 25.2 wt%) were fabricated by a facile sol−gel method employing natural cellulose substance (e. g., filter paper) as template. Thin VxOy/SnO2 gel layer was first deposited onto the surfaces of the cellulose microfibers of the filter paper through a dipping process, and then the as‐prepared VxOy/SnO2/cellulose composites were calcined in air to give the SnO2/V2O5 composites. The obtained composites inherit the morphology of the initial cellulose substance on the micrometer scale and consist of intricate microtubes composed of V2O5 nanorods with SnO2 nanoparticles anchored on the surfaces. Due to the unique three‐dimensional network structure of the composites and the synergetic effect of the V2O5 and SnO2 species, the SnO2/V2O5 composites displayed enhanced electrochemical performances when employed as cathode materials for lithium‐ion batteries. The composite with a SnO2 loading content of 12.1 wt% retained a stable discharge capacity of 126 mAh g−1 after 150 discharge/charge cycles at a current density of 0.1 A g−1. The three‐dimensional microtubular structure inherited from the cellulose substance improves the structural stability of the electrode materials and facilitates the diffusion of lithium ions, and the existence of SnO2 with an appropriate loading content enhances the conductivity of the composites.
Revolving Vernier Mechanism Controls Size of Linear Homomultimer
Authors: Uchida Takeo , Abe Keita , Endo Yuma , Ichiseki Shosei , Akita Satoru , Liu Shiyun , Aradachi Sho , Saito Masataka , Fukuchi Akihiko , Kikkawa Taiyo , Dammaretz Theo , Kawamata Ibuki , Suzuki Yuki , Nomura Shin‐ichiro M. , Murata Satoshi
Published: September 2017

A new kind of the Vernier mechanism that is able to control the size of linear assembly of DNA origami nanostructures is proposed. The mechanism is realized by mechanical design of DNA origami, which consists of a hollow cylinder and a rotatable shaft in it connected through the same scaffold. This nanostructure stacks with each other by the shape complementarity at its top and bottom surfaces of the cylinder, while the number of stacking is limited by twisting angle of the shaft. Experiments have shown that the size distribution of multimeric assembly of the origami depends on the twisting angle of the shaft; the average lengths of the multimer are decamer, hexamer, and tetramer for 0°, 10°, and 20° twist, respectively. In summary, it is possible to affect the number of polymerization by adjusting the precise shape and movability of a molecular structure.
Approaching Big Survey Data One Byte at a Time
Authors: Blaich Charles , Wise Kathleen
Published: September 2017

This chapter asserts that data are more likely to improve learning when assessment focuses on sensemaking conversations among students, faculty, and student affairs administrators, rather than on advanced statistical techniques.
Improving the Campus Climate for LGBTQ Students Using the Campus Pride Index
Authors: Garvey Jason C. , Rankin Susan , Beemyn Genny , Windmeyer Shane
Published: September 2017

This chapter describes how institutions can best use data from the Campus Pride Index, focusing on student recruitment and resource/policy advocacy for LGBTQ constituencies.
Leveraging Student Interfaith Cooperation Through Evidence‐Based Change
Authors: Crandall Rebecca E. , Correia‐Harker Benjamin P. , Mayhew Matthew J. , Rockenbach Alyssa N.
Published: September 2017

This chapter is tailored to student affairs professionals who are seeking to leverage students’ interfaith cooperation through evidence‐based change.