bluuebunny/crossref_metadata_2025 huggingface dataset:
Pulmonary Delivery of siRNA via Polymeric Vectors as Therapies of Asthma
Authors: Xie Yuran , Merkel Olivia M.
Published: July 2015

Asthma is a chronic inflammatory disease. Despite the fact that current therapies, such as the combination of inhaled corticosteroids and β2‐agonists, can control the symptoms of asthma in most patients, there is still an urgent need for an alternative anti‐inflammatory therapy for patients who suffer from severe asthma but lack acceptable response to conventional therapies. Many molecular factors are involved in the inflammatory process in asthma, and thus blocking the function of these factors could efficiently alleviate airway inflammation. RNA interference (RNAi) is often thought to be the answer in the search for more efficient and biocompatible treatments. However, difficulties of efficient delivery of small interference RNA (siRNA), the key factor in RNAi, to target cells and tissues have limited its clinical application. In this review, we summarize cytokines and chemokines, transcription factors, tyrosine kinases, and costimulatory factors that have been reported as targets of siRNA‐mediated treatment in experimental asthma. Additionally, we conclude several targeted delivery systems of siRNA to specific cells such as T cells, macrophages, and dendritic cells, which could potentially be applied in asthma therapy.
Distributed or concentrated research excellence? Evidence from a large‐scale research assessment exercise
Authors: Bonaccorsi Andrea , Cicero Tindaro
Published: July 2015

Almost all research evaluation exercises, by construction, deliver data at the level of departments and universities, not at the level of individuals. Yet, the aggregate performance is the average of the performance of individual researchers. This paper explores the issue of the relative magnitude of variability in performance within departments and between departments. It exploits anonymized data at the individual level from one of the largest research evaluation exercises, the Italian VQR 2004–2010 (Valutazione della Qualità della Ricerca). If the variability between departments were much larger than variability within departments, we would see evidence of a process of stratification, or vertical differentiation, arguably driven by competition and researcher mobility. The data show that the opposite pattern is at play.
Understanding the sustained use of online health communities from a self‐determination perspective
Authors: Zhang Yan
Published: July 2015

Sustained use of an information source is sometimes important for achieving an individual's long‐term goals, such as learning and self‐development. It is even more important for users of online health communities because health benefits usually come with sustained use. However, little is known about what retains a user. We interviewed 21 participants who had been using online diabetes communities in a sustained manner. Guided by self‐determination theory, which posits that behaviors are sustained when they can satisfy basic human needs for autonomy, competence, and relatedness, we identified mechanisms that help satisfy these needs, and thus sustain users in online health communities. Autonomy‐supportive mechanisms include being respected and supported as a unique individual, feeling free in making choices, and receiving meaningful rationales about others' decisions. Competence‐cultivating mechanisms include seeking information, providing information, and exchanging information with others to construct knowledge. Mechanisms that cultivate relatedness include seeing similarities between oneself and peers, receiving responses from others, providing emotional support, and forming small underground groups for closer interactions. The results suggest that, like emotions, information and small group interactions also play a key role in retaining users. System design and community management strategies are discussed based on these mechanisms.
The role of social capital in selecting interpersonal information sources
Authors: Zimmer J. Christopher , Henry Raymond M.
Published: July 2015

Although the information‐seeking literature has tended to focus upon the selection and use of inanimate objects as information sources, this research follows the more recent trend of investigating how individuals evaluate and use interpersonal information sources. By drawing from the structural, relational, and cognitive elements of social capital theory to inform antecedents to information quality and source accessibility, a research model is developed and tested. For interpersonal information sources, information quality is the key determinant of source use. Perceptions of information quality and accessibility of an interpersonal source are shown to be influenced by boundary spanning, transactive memory, and content type. Implications and prescriptions for future research are discussed.
Fabrication of Mesoporous CoS2 Nanotube Arrays as the Counter Electrodes of Dye‐Sensitized Solar Cells
Authors: Tsai Jung‐Che , Hon Min‐Hsiung , Leu Ing‐Chi
Published: July 2015

Mesoporous cobalt sulfide nanotube arrays on FTO‐coated glass were synthesized by combining three simple technologies: the selective etching of ZnO sacrificial templates, mesoporous Co3O4 formation from cobalt‐chelated chitosan, and ion‐exchange reaction (IER). The mesoporous Co3O4 nanotubes composed of the Co3O4 nanoparticles possess a high surface area and are taken advantage for further removal of templates and IER. The morphologies and crystal structures of the CoS2 nanotube arrays were characterized by SEM, TEM, and XRD analyses. Their electrocatalytic properties were determined by electrochemical analyses including cyclic voltammetry measurements and Tafel polarization. The DSSCs assembled with a CoS2 counter electrode achieved a power conversion efficiency of 6.13 %, which was comparable to that of the DSSC with the Pt counter electrode (6.04 %). This indicates that the mesoporous CoS2 nanotube array can be a low‐cost and efficient alternative for the reduction of electrolytes in DSSCs.
AgBi(WO4)2: A New Modification Material to Bi2WO6 for Enhanced and Stable Visible‐Light Photocatalyic Performance
Authors: Feng Cuiyun , Dong Yuming , Jiang Pingping , Wang Guangli , Zhang Jingjing , Wu Xiuming , Zhang Chi
Published: July 2015

In this work, we report a novel AgBi(WO4)2–Bi2WO6 heterostructure, which was designed and synthesized by using a simple hydrothermal method. Methyl orange was used as a representative dye indicator to evaluate the visible‐light catalytic activity and the catalytic mechanism was investigated. The as‐synthesized AgBi(WO4)2–Bi2WO6 composite displayed a 43 times higher photocatalytic activity than Bi2WO6. Owing to the matched band gap and distinctive heterostructure, AgBi(WO4)2–Bi2WO6 reveals a high visible‐light response and high‐efficiency utilization of both photogenerated electrons and holes. AgBi(WO4)2 reveals a similar energy level to and good lattice match with Bi2WO6, which are favorable qualities for band bending and fluent electron transfer. Furthermore, the photoexcited electrons can produce oxygen to generate .O2− radicals, which is vital for the overall utilization of both holes and electrons. This is the first example of AgBi(WO4)2 being used as photocatalytic material.
DNA Methylation Analysis of HTR2A Regulatory Region in Leukocytes of Autistic Subjects
Authors: Hranilovic Dubravka , Blazevic Sofia , Stefulj Jasminka , Zill Peter
Published: July 2015

Disturbed brain and peripheral serotonin homeostasis is often found in subjects with autism spectrum disorder (ASD). The role of the serotonin receptor 2A (HTR2A) in the regulation of central and peripheral serotonin homeostasis, as well as its altered expression in autistic subjects, have implicated the HTR2A gene as a major candidate for the serotonin disturbance seen in autism. Several studies, yielding so far inconclusive results, have attempted to associate autism with a functional SNP −1438 G/A (rs6311) in the HTR2A promoter region, while possible contribution of epigenetic mechanisms, such as DNA methylation, to HTR2A dysregulation in autism has not yet been investigated. In this study, we compared the mean DNA methylation within the regulatory region of the HTR2A gene between autistic and control subjects. DNA methylation was analysed in peripheral blood leukocytes using bisulfite conversion and sequencing of the HTR2A region containing rs6311 polymorphism. Autistic subjects of rs6311 AG genotype displayed higher mean methylation levels within the analysed region than the corresponding controls (P < 0.05), while there was no statistically significant difference for AA and GG carriers. Our study provides preliminary evidence for increased HTR2A promoter methylation in leukocytes of a portion of adult autistic subjects, indicating that epigenetic mechanisms might contribute to HTR2A dysregulation observed in individuals with ASD. Autism Res 2016, 9: 204–209. © 2015 International Society for Autism Research, Wiley Periodicals, Inc.
Effect of methylene group insertions on the structural rigidity of Aib containing helices
Authors: Duley Anju , Gowda Vasantha , Ganjiwale Anjali , Raghothama Srinivasarao , Ramanathan Gurunath
Published: July 2015

Nonprotein amino acids are being extensively used in the design of synthetic peptides to create new structure mimics. In this study we report the effect of methylene group insertions in a heptapeptide Boc‐Ala1‐Leu2‐Aib3‐Xxx4‐Ala5‐Leu6‐Aib7‐OMe which nicely folds into a mixed 310‐/α‐helical structure when Xxx= Ala. Analogs of this peptide have been made and studied by replacing central Xxx4 residue with Glycine (α‐residue), β‐Alanine (β‐Αla), γ‐aminobutyric acid (Gaba), and ε‐aminocaproic acid (ε‐Aca). NMR and circular dichroism were used to study the solution structure of these peptides. Crystals of the peptides containing alanine, β‐Αla, and Gaba reveal that increasing the number of central methylene (‐CH2‐) groups introduces local perturbations even as the helical structure is retained. © 2015 Wiley Periodicals, Inc. Biopolymers (Pept Sci) 104: 720–732, 2015.
Neighbor‐directed histidine N (τ)–alkylation: A route to imidazolium‐containing phosphopeptide macrocycles
Authors: Qian Wen‐Jian , Park Jung‐Eun , Grant Robert , Lai Christopher C. , Kelley James A. , Yaffe Michael B. , Lee Kyung S. , Burke Terrence R.
Published: July 2015

Our recently discovered, selective, on‐resin route to N(τ)‐alkylated imidazolium‐containing histidine residues affords new strategies for peptide mimetic design. In this, we demonstrate the use of this chemistry to prepare a series of macrocyclic phosphopeptides, in which imidazolium groups serve as ring‐forming junctions. Interestingly, these cationic moieties subsequently serve to charge‐mask the phosphoamino acid group that directed their formation. Neighbor‐directed histidine N(τ)‐alkylation opens the door to new families of phosphopeptidomimetics for use in a range of chemical biology contexts. © 2015 Wiley Periodicals, Inc. Biopolymers (Pept Sci) 104: 663–673, 2015.
Application of gas diffusion electrodes in bioelectrochemical syntheses and energy conversion
Authors: Horst Angelika E.W. , Mangold Klaus‐Michael , Holtmann Dirk
Published: July 2015

Combining the advantages of biological components (e.g., reaction specificity, self‐replication) and electrochemical techniques in bioelectrochemical systems offers the opportunity to develop novel efficient and sustainable processes for the production of a number of valuable products. The choice of electrode material has a great impact on the performance of bioelectrochemical systems. In addition to the redox process at the electrodes, interactions of biocatalysts with electrodes (e.g., enzyme denaturation or biofouling) need to be considered. In recent years, gas diffusion electrodes (GDEs) have proved to be very attractive electrodes for bioelectrochemical purposes. GDEs are porous electrodes, that posses a large three‐phase boundary surface. At this interface, a solid catalyst supports the electrochemical reaction between gaseous and liquid phase. This mini‐review discusses the application of GDEs in microbial and enzymatic fuel cells, for microbial electrolysis, in biosensors and for electroenzymatic synthesis reactions. Biotechnol. Bioeng. 2016;113: 260–267. © 2015 Wiley Periodicals, Inc.
Long‐term maintenance of a microfluidic 3D human liver sinusoid
Authors: Prodanov Ljupcho , Jindal Rohit , Bale Shyam Sundhar , Hegde Manjunath , McCarty William J. , Golberg Inna , Bhushan Abhinav , Yarmush Martin L. , Usta Osman Berk
Published: July 2015

The development of long‐term human organotypic liver‐on‐a‐chip models for successful prediction of toxic response is one of the most important and urgent goals of the NIH/DARPA's initiative to replicate and replace chronic and acute drug testing in animals. For this purpose, we developed a microfluidic chip that consists of two microfluidic chambers separated by a porous membrane. The aim of this communication is to demonstrate the recapitulation of a liver sinusoid‐on‐a‐chip, using human cells only for a period of 28 days. Using a step‐by‐step method for building a 3D microtissue on‐a‐chip, we demonstrate that an organotypic in vitro model that reassembles the liver sinusoid microarchitecture can be maintained successfully for a period of 28 days. In addition, higher albumin synthesis (synthetic) and urea excretion (detoxification) were observed under flow compared to static cultures. This human liver‐on‐a‐chip should be further evaluated in drug‐related studies. Biotechnol. Bioeng. 2016;113: 241–246. © 2015 Wiley Periodicals, Inc.
Real‐time imaging of anti‐biofilm effects using CP‐OCT
Authors: Rasmussen Karin , Reilly Cavan , Li Yuping , Jones Robert S.
Published: July 2015

The objective of this study was to develop a method to reliably and reproducibly assess the physical properties of in vitro multi‐species plaque derived biofilms. A custom flow cell (FC) was designed to model oral cavity shear stresses on biofilms grown on hydroxyapatite (HA) discs. A finite‐element program (ANSYS 13) modeled flow velocities and wall shear stresses on the interior 3D dimensions. For the experiment, 1% chlorhexidine (CHX), 5 M urea, and a 1× phosphate‐buffered saline (PBS) were flown through the FC simulating oral rinsing. Near infrared cross‐polarization optical coherence tomography (CP‐OCT) non‐destructively imaged the fluid immersed biofilms in real time (20 frames/s). During low flow, the swell of the biofilm caused from 5 M urea was quite pronounced increase in vertical dimension. Biofilms exposed to 1% CHX showed a slight collapse in the vertical dimension of the biofilm during low flow. During high flow/high sheer stress, the 5 M urea solution effectively removed the biofilm, while both 1% CHX and 1× PBS did not remove biofilms even under high velocity/shear stress conditions. Biotechnol. Bioeng. 2016;113: 198–205. © 2015 Wiley Periodicals, Inc.
Association between volume of severely injured patients and mortality in German trauma hospitals
Authors:   TraumaRegister DGU®, Zacher M T , Kanz K-G , Hanschen M , Häberle S , van Griensven M , Lefering R , Bühren V , Biberthaler P , Huber-Wagner S
Published: July 2015

Background

The issue of patient volume related to trauma outcomes is still under debate. This study aimed to investigate the relationship between number of severely injured patients treated and mortality in German trauma hospitals.

Methods

This was a retrospective analysis of the TraumaRegister DGU® (2009–2013). The inclusion criteria were patients in Germany with a severe trauma injury (defined as Injury Severity Score (ISS) of at least 16), and with data available for calculation of Revised Injury Severity Classification (RISC) II score. Patients transferred early were excluded. Outcome analysis (observed versus expected mortality obtained by RISC-II score) was performed by logistic regression.

Results

A total of 39 289 patients were included. Mean(s.d.) age was 49·9(21·8) years, 27 824 (71·3 per cent) were male, mean(s.d.) ISS was 27·2(11·6) and 10 826 (29·2 per cent) had a Glasgow Coma Scale score below 8. Of 587 hospitals, 98 were level I, 235 level II and 254 level III trauma centres. There was no significant difference between observed and expected mortality in volume subgroups with 40–59, 60–79 or 80–99 patients treated per year. In the subgroups with 1–19 and 20–39 patients per year, the observed mortality was significantly greater than the predicted mortality (P < 0·050). High-volume hospitals had an absolute difference between observed and predicted mortality, suggesting a survival benefit of about 1 per cent compared with low-volume hospitals. Adjusted logistic regression analysis (including hospital level) identified patient volume as an independent positive predictor of survival (odds ratio 1·001 per patient per year; P = 0·038).

Conclusion

The hospital volume of severely injured patients was identified as an independent predictor of survival. A clear cut-off value for volume could not be established, but at least 40 patients per year per hospital appeared beneficial for survival.
Engaging novice researchers in the process and culture of science using a “Pass‐the‐Problem” case strategy
Authors: White Harold B. , Usher David C.
Published: July 2015

Undergraduates having their first research experience frequently have little idea of what to expect. Institutions offering summer research experiences attempt to address this issue through programs that introduce students to the process and culture of science. However, didactic approaches frequently bore students who prefer more interactive sessions. We describe a “Pass‐the‐Problem” case study approach that engages groups of students in useful discussions about the research environment they are entering. The cases presented here include keeping a thorough laboratory notebook, balancing laboratory and personal time demands, anxiety about formal presentations, unexpected federal regulatory inspection, working in a lab with limited funds, being used as a technician rather than a researcher, frustration with failed experiments, effects of promotion and tenure on laboratory atmosphere, the importance of reading the research literature, and questioning a career in science. These cases alert students to different situations they might encounter and stimulate discussion about how to deal with them. © 2015 by The International Union of Biochemistry and Molecular Biology, 43(5):341–344, 2015.
Continuous Synthesis and Thermal Elimination of Sulfinyl‐Route Poly(p‐Phenylene Vinylene) in Consecutive Flow Reactions
Authors: Zaquen Neomy , Baeten Evelien , Vandenbergh Joke , Lutsen Laurence , Vanderzande Dirk , Junkers Tanja
Published: July 2015

Continuous synthesis of multistep polymerizations at microscale is made available by coupling two microstructured chip reactors in a single reactor setup. Conjugated [2‐methoxy‐5‐(3′,7′‐dimethyloctyloxy)]‐1,4‐phenylenevinylene (MDMO‐PPV) is synthesized via the radical sulfinyl precursor route. Reactions are carried out in separate reactors and optimization of the elimination of polymer can be effectively performed in a defined temperature range, allowing for full polymer conversion within minutes and formation of conjugated materials. The combination of both processes in a single coupled reactor setup permits total monomer‐to‐conjugated‐MDMO‐PPV conversions while retaining its pristine optical properties. Polymer characteristics are comparatively good and the reduction in yield due to the lower initial monomer concentrations is compensated by the much shorter reaction times required in the flow process.
Controlled Construction of Hierarchical Nanocomposites Consisting of MnO2 and PEDOT for High‐Performance Supercapacitor Applications
Authors: Tang Pengyi , Han Lijuan , Zhang Lin , Wang Shijie , Feng Wei , Xu Guoqing , Zhang Li
Published: July 2015

The front cover artwork is provided by the group of Professor Li Zhang from The Chinese University of Hong Kong and his collaborators from the Shenzhen Institutes of Advanced Technology, Chinese Academy of Science. The image shows the fabrication of core–shell–branch hierarchical MnO2@PEDOT@MnO2 nanocomposites, using simple electrochemical deposition for supercapacitor applications. Read the full text of the Article at 10.1002/celc.201500025.
Color specification of a single strand of yarn from a multispectral image
Authors: Luo Lin , Shen Hui‐Liang , Shao Si‐Jie , Xin John H.
Published: July 2015

Many applications in textile require color measurement of single strands of yarns due to unavailability of a mass of consecutive yarns. While multispectral imaging systems can capture images of single strands of yarns, an unavoidable problem accompanied is how to specify their colors from images, in which pixel values vary with positions owing to three‐dimensional shape of yarn. Based on the response of multispectral imaging systems to single strands of yarns, this article formulates the color specification problem as an optimization question and four methods are proposed: average of all pixels (AA), average of pixels in central area (AC), maxima of all pixels (MA), and lightness weighting method (LW). The first experiment analyzed color distribution of pixels on a single strand of yarn. Experimental results show pixels in central area have smallest color variation and largest intensity. The second experiment compared the proposed methods. Results show that CIEXYZ, L*, and C* values specified by the AA and MA methods are lowest and highest. Finally, colors of single strands of yarns specified by the proposed methods were compared with spectrophotometric colors of yarn windings using 12 pairs of single strands of yarns and yarn windings. Experimental results show the MA method yields the smallest lightness and chroma difference compared with spectrophotometric colors of yarn windings. The average color difference between spectrophotometric colors of yarn windings and multispectral imaging colors of single strands of yarns specified by the AA, AC, MA, and LW methods is 3.45, 2.72, 2.37, and 3.33 CMC(2:1) units. © 2015 Wiley Periodicals, Inc. Col Res Appl, 41, 500–512, 2016
An error‐tolerant keyword search scheme based on public‐key encryption in secure cloud computing
Authors: Bo Yang , Zhang Mingwu , Du Jun‐Qiang
Published: July 2015

An error‐tolerant keyword search scheme permits to make searches on encrypted data with only an approximation of some keyword. The scheme is suitable to the case where users' searching input might not exactly match those pre‐set keywords. An error‐tolerant keyword search scheme can be generated based on a public‐key encryption scheme, in which anyone with access to a user's public key can generate the trapdoors and indexes to keywords, and only the user holding the decryption key can obtain the records it retrieves. In this paper, we first present a general framework for searching on error‐tolerant keywords based on a public‐key encryption scheme. Then, we propose a concrete scheme based on the Cramer–Shoup cryptosystem. The scheme is adaptive chosen‐ciphertext attack secure and suitable for all similarity metrics including Hamming distance metric, edit distance metric, and set difference metric. It does not require the user to construct and store anything in advance, other than the cryptosystem used to calculate the trapdoor of keywords and to encrypt data documents. Thus, our scheme tremendously eases the users' burden. What is more, our scheme is able to transform the servers' searching for error‐tolerant keywords on ciphertexts to searching for exact keywords on plaintexts. The server can use any existing approaches of exact keywords search to search plaintexts on an index table. Copyright © 2015 John Wiley & Sons, Ltd.
Fractality and self‐organization in the orthodox iconography
Authors: Milovanović Miloš , Tomić Bojan M.
Published: July 2015

The authors consider the Orthodox iconography of Byzantine style aimed at examining the existence of complex behavior and fractal patterns. It has been demonstrated that fractality in icons is manifested as two types—descending and ascending, where the former one corresponds to the apparent information and the latter one to the hidden causal information defining the spatiality of icon. Self‐organization, recognized as the increase of the causal information in temporal domain, corresponds to contextualization of the observer's personage position. The results presented in the forms of plots and tables confirm the adequacy of the model being the completion of visual perception. © 2015 Wiley Periodicals, Inc. Complexity 21: 55–68, 2016
To address emerging infections, we must invest in enduring systems: The kinetics and dynamics of health systems strengthening
Authors: Pastakia S , Njuguna B , Le PV , Singh MK , Brock TP
Published: July 2015

Clinical pharmacology uses foundational principles of pharmacokinetics (PK) and pharmacodynamics (PD) to address medication use spanning a continuum from molecules to the masses. In the realm of infectious diseases, PK/PD attributes are considered especially important, because subtherapeutic dosing of antibiotics has been associated with poorer clinical outcomes in patients and increased incidences of drug resistance in populations. In consideration of these PK/PD principles, we will describe the analogous relationship between health systems strengthening, including for educating healthcare providers about emerging infections, and the tenets of therapeutic drug monitoring.
Estimating the real crystal radius from the weight signal in a course of growth process by the Stepanov (EFG) technique
Authors: Rossolenko S.N. , Stryukov D.O. , Kurlov V.N.
Published: July 2015

The method of estimating the real radius from the weight signal in a course of growth by the Stepanov (EFG) technique is developed. The transitional portion of the cylindrical crystal was grown during which calculation of changing real radius was carried out. Comparison of the real profile with calculated one was made.
CCRA: channel criticality based resource allocation in cognitive radio networks
Authors: Kumar Vinesh , Minz Sonajharia
Published: July 2015

In cognitive radio networks, signal to interference plus noise ratio (SINR) is a quantity that is used to analyze the bounds of the capacity of a channel. This is the reason for SINR being one of the important parameters toward evaluating the performance of spectrum sharing in every network. To maximize the channel utilization in any network, the SINR of a channel should be considered to be within a threshold. This also leads to lesser power consumption, and the quality of service for the licensed users is maintained. Further, reduced SINR leads to an improvement in the quality of communication in the network. In this paper, a graph theoretic measure for the efficient utilization of channels in cognitive radio networks has been proposed and is named as channel criticality based resource allocation (CCRA). Using the SINR as the weight of the graph, a novel concept of channel criticality has also been introduced in this work. The proposed CCRA technique has also been compared with the existing interference aware channel assignment (IACA) technique in terms of the channel utilization. Through simulations, the CCRA has been observed to outperform the IACA scheme. The average channel utilization of the proposed CCRA was observed to have increased by 8%, when the secondary users were introduced in the network as compared with the IACA technique. Copyright © 2015 John Wiley & Sons, Ltd.
Hybridization in closely related Rhododendron species: half of all species‐differentiating markers experience serious transmission ratio distortion
Authors: Marczewski Tobias , Chamberlain David F. , Milne Richard I.
Published: July 2015

An increasing number of studies of hybridization in recent years have revealed that complete reproductive isolation between species is frequently not finalized in more or less closely related organisms. Most of these species do, however, seem to retain their phenotypical characteristics despite the implication of gene flow, highlighting the remaining gap in our knowledge of how much of an organism's genome is permeable to gene flow, and which factors promote or prevent hybridization. We used AFLP markers to investigate the genetic composition of three populations involving two interfertile Rhododendron species: two sympatric populations, of which only one contained hybrids, and a further hybrid‐dominated population. No fixed differences between the species were found, and only 5.8% of the markers showed some degree of species differentiation. Additionally, 45.5% of highly species‐differentiating markers experienced significant transmission distortion in the hybrids, which was most pronounced in F1 hybrids, suggesting that factors conveying incompatibilities are still segregating within the species. Furthermore, the two hybrid populations showed stark contrasting composition of hybrids; one was an asymmetrically backcrossing hybrid swarm, while in the other, backcrosses were absent, thus preventing gene flow.
Sperm storage and spermatozoa interaction with epithelial cells in oviduct of Chinese soft‐shelled turtle, Pelodiscus sinensis
Authors: Chen Shaofan , Zhang Linli , Le Yuan , Waqas Yasir , Chen Wei , Zhang Qian , Ullah Shakeeb , Liu Tengfei , Hu Lisi , Li Quanfu , Yang Ping
Published: July 2015

Spermatozoa are known to be stored within the female genital tract after mating in various species to optimize timing of reproductive events such as copulation, fertilization, and ovulation. The mechanism supporting long‐term sperm storage is still unclear in turtles. The aim of this study was to investigate the interaction between the spermatozoa and oviduct in Chinese soft‐shelled turtle by light and electron microscopy to reveal the potential cytological mechanism of long‐term sperm storage. Spermatozoa were stored in isthmus, uterine, and vagina of the oviduct throughout the year, indicating long‐term sperm storage in vivo. Sperm heads were always embedded among the cilia and even intercalated into the apical hollowness of the ciliated cells in the oviduct mucosal epithelium. The stored spermatozoa could also gather in the gland conduit. There was no lysosome distribution around the hollowness of the ciliated cell, suggesting that the ciliated cells of the oviduct can support the spermatozoa instead of phagocytosing them in the oviduct. Immune cells were sparse in the epithelium and lamina propria of oviduct, although few were found inside the blood vessel of mucosa, which may be an indication of immune tolerance during sperm storage in the oviduct of the soft‐shelled turtle. These characteristics developed in the turtle benefited spermatozoa survival for a long time as extraneous cells in the oviduct of this species. These findings would help to improve the understanding of reproductive regularity and develop strategies of species conservation in the turtle. The Chinese soft‐shelled turtle may be a potential model for uncovering the mechanism behind the sperm storage phenomenon.
Low levels of hybridization between sympatricArctic char (Salvelinus alpinus) andDollyVarden char (Salvelinus malma) highlights their genetic distinctiveness and ecological segregation
Authors: May‐McNally Shannan L. , Quinn Thomas P. , Taylor Eric B.
Published: July 2015

Understanding the extent of interspecific hybridization and how ecological segregation may influence hybridization requires comprehensively sampling different habitats over a range of life history stages. Arctic char (Salvelinus alpinus) and Dolly Varden (S. malma) are recently diverged salmonid fishes that come into contact in several areas of the North Pacific where they occasionally hybridize. To better quantify the degree of hybridization and ecological segregation between these taxa, we sampled over 700 fish from multiple lake (littoral and profundal) and stream sites in two large, interconnected southwestern Alaskan lakes. Individuals were genotyped at 12 microsatellite markers, and genetic admixture (Q) values generated through Bayesian‐based clustering revealed hybridization levels generally lower than reported in a previous study (<0.6% to 5% of samples classified as late‐generation hybrids). Dolly Varden and Arctic char tended to make different use of stream habitats with the latter apparently abandoning streams for lake habitats after 2–3 years of age. Our results support the distinct biological species status of Dolly Varden and Arctic char and suggest that ecological segregation may be an important factor limiting opportunities for hybridization and/or the ecological performance of hybrid char.
The effect of hydroperiod and predation on the diversity of temporary pond zooplankton communities
Authors: Zokan Marcus , Drake John M.
Published: July 2015

In temporary pond ecosystems, it is hypothesized that the two dominant structuring forces on zooplankton communities are predation and demographic constraints due to wetland drying. Both of these forces are deterministic processes that act most strongly at opposing ends of a hydroperiod gradient. Our objective was to test how these two processes affect α‐ and β‐diversity of zooplankton communities derived from a diverse temporary pond system. We hypothesized that decreased hydroperiod length and the presence of salamander larvae as predators would decrease β‐diversity and that intermediate hydroperiod communities would have the greatest species richness. Our 1‐year mesocosm experiment (n = 36) consisted of two predation treatments (present/absent) and three hydroperiod treatments (short/medium/long) fully crossed, seeded from the resting egg bank of multiple temporary ponds. In total, we collected 37 species of microcrustacean zooplankton from our mesocosms. A reduction in hydroperiod length resulted in lower α‐diversity, with short‐hydroperiod treatments affected most strongly. Endpoint community dissimilarity (β‐diversity) was greatest in the medium‐hydroperiod treatment with regard to species presence/absence, but was greatest in the long‐hydroperiod treatment when abundances were included. Predation by salamander larvae led to reduced β‐diversity with respect to species presence/absence, but not among abundant species, and had no effect on α‐diversity. Our results suggest that environmental changes that reduce hydroperiod length would result in reduced α‐diversity; however, intermediate hydroperiod length appear to enhance β‐diversity within a group of wetlands.
Fat crystal network structures have a strong influence on properties of fat‐based barrier layers
Authors: Franke Knut , Bindrich Ute , Heinz Volker
Published: July 2015

Mixtures of low and high melting fats (fractions of palm fat, palm kernel fat, and milk fat) were characterized after solidification with respect to solid fat content (SFC), firmness, barrier properties against moisture transport, and fat crystal network structure (FCNS). The method of detrended fluctuation analysis (DFA) was applied to quantify FCNS which was visualized using confocal laser scanning microscopy (CLSM). A broad range of firmness of solidified fat mixtures could be observed for comparable SFC confirming the influence of FCNS. Smooth FCNS without dense crystals indicate firmer networks and vice versa. A correlation between the scaling exponent from DFA and firmness was found. Moisture barrier properties of the fat mixtures differed for similar SFC, too. In this case, FCNS with dense crystals and larger areas of interconnected liquid fat resulted in the best barrier effect. Smooth FCNS were found in fat blends possessing only low resistance against moisture transport. For SFC > 35% at 20°C, a linear correlation between scaling exponent and moisture barrier effect was detectable.

Practical applications: These results can be used to optimize fat mixtures with respect to their performance and define the fat crystal network structures which are required to obtain either high mechanical firmness of the solidified mixture or an efficient prevention of moisture transfer.

Confocal laser scanning microscopy (CLSM) images reveal very different fat crystal network structures of solidified fat blends possessing similar solid fat contents. Smooth structures on the left hand side result in blends with a high firmness, whereas structures with many dense crystals (black spots) and interconnected areas of liquid fat (light red regions) on the right hand side indicate networks with lower firmness.
In vitro characterization of five bacterial WS/DGAT acyltransferases regarding the synthesis of biotechnologically relevant short‐chain‐length esters
Authors: Röttig Annika , Wolf Sebastian , Steinbüchel Alexander
Published: July 2015

For the biotechnical production of biofuels, oleo‐, or fine chemicals bacterial wax ester synthase/acyl‐Coenzyme A:diacylglycerol acyltransferases (WS/DGAT) are discussed as interesting candidates for in vivo esterification reactions. In this study, the suitability of selected acyltransferases for the conversion of non‐physiological substrates like short‐chain‐length alcohols and short‐chain length or even branched acyl‐CoAs has been investigated. In vitro analyzes of purified AtfA and AtfA(G355I) from Acinetobacter baylyi, Ma1(A360I) from Marinobacter aquaeolei, WS2 from Marinobacter hydrocarbonoclasticus, and AtfA1 from Alcanivorax borkumensis were conducted to evaluate the specific activities of these enzymes toward n‐hexadecanol (C16), n‐dodecanol (C12), ethanol (C2), and methanol (C1), palmitoyl‐CoA (C16), butyryl‐CoA (C4) as well as toward branched 3‐hydroxybutyryl‐CoA and 2‐hydroxyisobutyryl‐CoA. Athough long‐ and medium‐chain‐length substrates were preferred by all five enzymes, WS2 and AtfA showed the highest relative activities with ethanol or methanol when compared to n‐hexadecanol, whereas residual activities toward short or branched acyl‐CoAs could only be measured with AtfA and AtfA1.

Practical applications: Bacterial WS/DGATs can be used for in vivo and in vitro approaches to synthesize custom‐made lipids, such as triglycerides or wax esters. However, due to their broad substrate ranges these enzymes are also promising candidates for the synthesis of other, industrially valuable oleo‐ and fine chemicals. Short‐chain‐length esters are important intermediates and building blocks for many production processes and, at present, there is a great demand for enzymes which are able to catalyze their synthesis.

The physiological substrates of bacterial WS/DGAT enzymes are medium‐ to long‐chain length acyl‐CoAs and fatty alcohols to synthesize medium‐ to long‐chain length wax esters. In this study, we investigated five different bacterial WS/DGATs for their ability to synthesize short‐chain length esters, which represent biotechnologically interesting compounds. The enzymes AtfA, AtfA(G355I), Ma1(A360I), WS2, and AtfA1 were selected, purified, and characterized in vitro. In addition to the reference substrates, hexadecanol and palmitoyl‐CoA, their activity with dodecanol, ethanol, or methanol, on the one hand, and lauryl‐CoA, butyryl‐CoA, 3‐hydroxybutyryl‐CoA, or 2‐hydroxyisobutyryl‐CoA, on the other hand, were studied and compared.
Classification of Tunisian extra virgin olive oils according to their genetic variety and maturity index using fatty acid profiles established by direct infusion mass spectrometry
Authors: Abdallah Marwa , Vergara‐Barberán María , Lerma‐García María Jesús , Herrero‐Martínez José Manuel , Simó‐Alfonso Ernesto F. , Guerfel Mokhtar
Published: July 2015

The usefulness of fatty acid profiles established by direct infusion mass spectrometry (DIMS) as a tool to discriminate between seven genetic varieties of Tunisian extra virgin olive oils (EVOOs) was evaluated in this work. Moreover, the discrimination of EVOOs from the genetic varieties Chemchali, Fouji, and Zarrazi, characterized with different maturity indices, was also studied. For DIMS, EVOO samples were diluted with an 85:15 propanol/methanol (v/v) mixture containing 40 mM ammonia and directly infused into the mass spectrometer using a syringe pump. The establishment of ratios of the peak abundances of the free fatty acids followed by linear discriminant analysis was employed to predict both genetic variety and maturity index. In all cases, an excellent resolution between all category pairs was achieved, which demonstrated that fatty acid profiles are a good marker of both genetic variety and maturity index of EVOOs.

Practical applications: As EVOO quality can be affected by different parameters, such as cultivar and maturity index, among others, it is necessary to develop analytical methods able to verify EVOO quality, and also to control its origin as olive oil producers have to include in their manufactured products the cultivar (monovarietal oils) from which the oil was obtained. Currently, almost all the research related to Tunisian EVOOs has been mainly focused on the improvement and characterization of the two main cultivars (Chétoui and Chemlali). Thus, to diversify Tunisian olive oil resources and improve the quality of olive oil produced in Tunisia, research on additional cultivars needs to be conducted. Thus, the present method could be used as an authentication tool for olive oil industry to asses both cultivar and maturity index of Tunisian EVOO, which could be extended to EVOO from all around the world.

DIMS data of Tunisian EVOOs were used to predict EVOO genetic variety and maturity index using LDA.
On the dimensioning of LTE and LTE‐advanced networks
Authors: Ben Hcine Marwane , Bouallegue Ridha
Published: July 2015

Network design consists of evaluating cell coverage and capacity and may involve many parameters related to environment, system configuration and quality of service requirements. The key parameter for cost optimised Long Term Evolution (LTE)‐based network dimensioning is to provide a tight approximation of the effective signal‐to‐interference‐plus‐noise ratio (SINR) distribution. This paper provides a novel framework for LTE and LTE‐advanced network dimensioning, where the classical single‐carrier SINR performance evaluation is extended to multi‐carriers systems operating over frequency selective channels. Extension is achieved by expressing the link outage probability in terms of the statistics of the effective SINR. For effective SINR computation, the exponential effective SINR mapping technique is used. Closed‐form expression for the link outage probability is achieved assuming a log skew normal approximation for single‐carrier case. Then we rely on the log‐normal approximation to express the exponential effective SINR distribution as a function of the mean and standard deviation of the SINR of a generic subcarrier. Effective SINR values are evaluated at click speed in each point on the network. Simulations show that the proposed framework provides results with accuracy within 0.5 dB for any defined outage probability target. Copyright © 2015 John Wiley & Sons, Ltd.
Overlapping coalition formation games‐based resource allocation for device‐to‐device communication in LTE‐A network
Authors: Xia Chunmei , Xu Shaoyi , Kwak Kyung Sup
Published: July 2015

In the long‐term evolution‐advanced system, device‐to‐device (D2D) communication brings many significant benefits, such as low power consumption, low delay, high bit rates and efficient frequency utilisation. However, these potential advantages hinge on the intelligent resource allocation approach between D2D user equipments (DUEs) and cellular user equipments (CUEs). Different from existing work that focused on the scenario that one CUE shares spectrums with one D2D pair and thus disjoint groups are formed to use spectrums, in our paper, we proposed a coalition formulation game with overlapping coalitions. In this game, we model the resource sharing problem as a transferable coalition formation game where there exists intersection among these coalitions and the DUEs can make a decision to join or leave a coalition according to the merge‐and‐split rule. Consequently, not only one D2D pair can employ the same resource with multiple CUEs but also the channel of one CUE can be allocated to multiple D2D pairs in order to maximise the frequency efficiency and the system sum throughput. In particular, we consider the practical case and study the effect that only imperfect channel state information (CSI) can be obtained on the stable coalition formation game. A discrete‐time Markov chain‐based analysis is presented to obtain the stable coalition structure, and the complexity of employing this scheme is evaluated. Extensive numerical results show that the proposed overlapping coalition formulation game‐based scheme results in better performance compared to the traditional existing methods even in the imperfect CSI scenarios. Copyright © 2015 John Wiley & Sons, Ltd.
Factors associated with depression in older carers
Authors: Loi Samantha M. , Dow Briony , Moore Kirsten , Hill Keith , Russell Melissa , Cyarto Elizabeth , Malta Sue , Ames David , Lautenschlager Nicola
Published: July 2015

Objective

Depression is an adverse outcome frequently seen in carers. With the increasing ageing population and reliance on informal carers, this study aims to identify factors associated with depression in carers in the older age group, using factors that have not been previously investigated.

Methods

We conducted a cross‐sectional analysis of 202 older carers using the Geriatric Depression scale, demographics, personality traits, attitudes to ageing and other carer characteristics.

Results

Increased hours spent caring and higher levels of neuroticism were all factors associated with depression. The care‐recipient diagnosis, other personality traits, attitudes to ageing, leisure‐physical activity (PA) and domestic‐PA were not significantly associated with depression.

Conclusions

These findings have important implications for interventions to target at‐risk carers. Copyright © 2015 John Wiley & Sons, Ltd.
Whose Risks and Benefits?
Authors: Kaebnick Gregory E.
Published: July 2015

This issue of the Report, like many others, was assembled with an eye more to diversity of topics and themes than to commonality. But as also often happens, some topics and themes arise anyway. Two pieces in this issue discuss the disclosure of information that's uncovered in the course of genetic testing and try to develop some guidance for physicians and researchers. A third offers an historical look at changing practices.
Responsible Stewards of a Limited Resource
Authors: Turnbull Jessica M.
Published: July 2015

I had heard rumblings of the possibility of consult on this patient. As a pediatric intensivist conducting consults for my institution's clinical bioethics service, I had come to appreciate that many low‐ to moderate‐level ethical dilemmas are present in the pediatric intensive care unit (PICU) every single day. Despite this, or maybe because of it, it takes quite a morally complicated situation to trigger a consult for the service.

Sam was a three‐month‐old who had been born full‐term without complications. In the weeks prior to admission, his parents found that he was not feeding well and at times struggled to catch his breath. At our institution's PICU, it was determined that his decline was secondary to dilated cardiomyopathy, for which he would require cardiac transplantation for survival. Sam's parents were unsure if putting him through a heart transplant was the right thing to do, but they were unable to tolerate the thought of losing him. After an extensive consent process, they decided to pursue cardiac transplantation.