bluuebunny/crossref_metadata_2025 huggingface dataset:
Traction Force Microscopy in 3‐Dimensional Extracellular Matrix Networks
Authors: Cóndor M. , Steinwachs J. , Mark C. , García‐Aznar J.M. , Fabry B.
Published: June 2017

Cell migration through a three‐dimensional (3‐D) matrix depends strongly on the ability of cells to generate traction forces. To overcome the steric hindrance of the matrix, cells need to generate sufficiently high traction forces but also need to distribute these forces spatially in a migration‐promoting way. This unit describes a protocol to measure spatial maps of cell traction forces in 3‐D biopolymer networks such as collagen, fibrin, or Matrigel. Traction forces are computed from the relationship between measured force‐induced matrix deformations surrounding the cell and the known mechanical properties of the matrix. The method does not rely on knowledge of the cell surface coordinates and takes nonlinear mechanical properties of the matrix into account. © 2017 by John Wiley & Sons, Inc.
Improving the Quantum Yields of Perylene Diimide Aggregates by Increasing Molecular Hydrophobicity in Polar Media
Authors: Xu Xiaoyu , Austin Ashli , Mylon Steven E. , Plenge Jürgen , Szarko Jodi M.
Published: June 2017

Here we report the quantum yield of four aggregated perylene diimide (PDI) species that vary by the length of the branched side chains attached at the N,N’ imide positions. The PDI molecules were dissolved in binary water:methanol solvents as a means to vary the solvent polarity and control the degree of aggregation in solution. By performing spectroscopy, kinetics, and light scattering experiments, the nature of the molecular interactions in the solutions was determined. The maximum quantum yield of the aggregated molecules increased from 0.04 for the shortest chain molecule (B2) to 0.20 for the largest chain molecule (B13). The higher quantum yield of B13 compared with B2 correlates well with an increase in the fluorescence lifetime. The monomer emission lifetime was 4.8 ns whereas a lifetime as high as 21.2 ns was measured for the B13 aggregate fluorescence. A shorter sub‐nanosecond lifetime was also measured for suspended colloids in B5, B9, and B13. The enhanced quantum yield is attributed to an increase of disorder in the B13 aggregates. As the polarity of the solution increases, the hydrophobic effect further enhances the disorder, and, therefore, the quantum yields in these particles.
Mouse Model of Burn Wound and Infection: Thermal (Hot Air) Lesion‐Induced Immunosuppression
Authors: Calum Henrik , Høiby Niels , Moser Claus
Published: June 2017

The immunosuppression induced by thermal injury renders the burned victim susceptible to infection. A mouse model was developed to examine the immunosuppression, which was possible to induce even at a minor thermal insult of 6% total body surface area. After induction of the burn (48 hr) a depression of leukocytes in the peripheral blood was found of the burned mice. This depression was due to a reduction in the polymorphonuclear cells. The burned mice were not able to clear a Pseudomonas aeruginosa wound infection, since the infection spread to the blood as compared to mice only infected with P. aeruginosa subcutaneously. The burn model offers an opportunity to study infections under these conditions. The present model can also be used to examine new antibiotics and immune therapy. Our animal model resembling the clinical situation is useful in developing new treatments of burn wound victims. © 2017 by John Wiley & Sons, Inc.
A Fast, Easy, and Customizable Eight‐Color Flow Cytometric Method for Analysis of the Cellular Content of Bronchoalveolar Lavage Fluid in the Mouse
Authors: Daubeuf François , Becker Julien , Aguilar‐Pimentel Juan Antonio , Ebel Claudine , Hrabě de Angelis Martin , Hérault Yann , Frossard Nelly
Published: June 2017

The cell composition of bronchoalveolar lavage fluid (BAL) is an important indicator of airway inflammation. It is commonly determined by cytocentrifuging leukocytes on slides, then staining, identifying, and counting them as eosinophils, neutrophils, macrophages, or lymphocytes according to morphological criteria under light microscopy, where it is not always easy to distinguish macrophages from lymphocytes. We describe here a one‐step, easy‐to‐use, and easy‐to‐customize 8‐color flow cytometric method for performing differential cell count and comparing it to morphological counts on stained cytospins. This method identifies BAL cells by a simultaneous one‐step immunolabeling procedure using antibodies to identify T cells, B cells, neutrophils, eosinophils, and macrophages. Morphological analysis of flow‐sorted cell subsets is used to validate this protocol. An important advantage of this basic flow cytometry protocol is the ability to customize it by the addition of antibodies to study receptor expression at leukocyte cell surfaces and identify subclasses of inflammatory cells as needed. © 2017 by John Wiley & Sons, Inc.
Monitoring Pathogen‐Induced Sickness in Mice and Rats
Authors: Kolmogorova Daria , Murray Emma , Ismail Nafissa
Published: June 2017

Sickness behavior monitoring, a technique for examining the development of sickness symptomatology following infection, is necessary in experiments studying neurochemical and physiological changes associated with pathogen‐induced immune activation. However, the results of sickness behavior monitoring are difficult to reconcile due to inconsistencies in protocol methods and rater bias. The protocol described herein offers a non‐invasive and unbiased approach to assess the progression of pathogen‐induced sickness behaviors. This simple, straightforward method uses a five‐point scale to assess animals for the presence of four sickness behaviors (i.e., ‘“0” = no sickness behaviors; “4” = four sickness behaviors) at various time points following exposure to a pathogen. This approach removes the ambiguity and bias inherent to other methods of sickness behavior monitoring that rely on subjective ratings of severity for individual symptoms. This protocol has been successfully applied to male and female rodents injected intraperitoneally with lipopolysaccharide and polyinosinic:polycytidylic acid, and has been effective in pubertal and adult populations. Protocols for changes in body temperature and weight are also provided as physiological markers of sickness. © 2017 by John Wiley & Sons, Inc.
Water‐Medium Synthesis of Nucleoside 5′‐Polyphosphates
Authors: Depaix Anaïs , Peyrottes Suzanne , Roy Béatrice
Published: June 2017

This unit describes a one‐pot, two step synthesis of ribonucleoside 5′‐di‐ and 5′‐triphosphates, as well as their purification. The first step of the synthesis involves the activation of an unprotected ribonucleoside 5′‐monophosphate with 2‐chloro‐1,3‐dimethylimidazolinium hexafluorophosphate and imidazole, in a mixture of water/acetonitrile. The resulting phosphorimidazolate intermediate is then treated with inorganic phosphate or pyrophosphate to afford the corresponding nucleoside 5′‐di‐ or 5′‐triphosphates. The attractive features of this strategy include the absence of protecting groups on the starting material and convenient set up (i.e., use of water, non‐dry solvents and reagents, commercially available sodium salts). © 2017 by John Wiley & Sons, Inc.
Nucleobase Protection of Deoxyribo‐ and Ribonucleosides
Authors: Meher Geeta , Meher Nabin K. , Iyer Radhakrishnan P.
Published: June 2017

Oligonucleotides carrying a variety of chemical modifications including conjugates are finding increasing applications in therapeutics, diagnostics, functional genomics, proteomics, and as research tools in chemical and molecular biology. The successful synthesis of oligonucleotides primarily depends on the use of appropriately protected nucleoside building blocks including the exocyclic amino groups of the nucleobases, the hydroxyl groups at the 2′‐, 3′‐, and 5′‐positions of the sugar moieties, and the internucleotide phospho‐linkage. This unit is a thoroughly revised update of the previously published version and describes the recent development of various protecting groups that facilitate reliable oligonucleotide synthesis. In addition, various protecting groups for the imide/lactam function of thymine/uracil and guanine, respectively, are described to prevent irreversible nucleobase modifications that may occur in the presence of reagents used in oligonucleotide synthesis. © 2017 by John Wiley & Sons, Inc.
Engineered Polymerases with Altered Substrate Specificity: Expression and Purification
Authors: Nikoomanzar Ali , Dunn Matthew R. , Chaput John C.
Published: June 2017

Polymerase engineering is making it possible to synthesize xeno‐nucleic acid polymers (XNAs) with diverse backbone structures and chemical functionality. The ability to copy genetic information back and forth between DNA and XNA has led to a new field of science known as synthetic genetics, which aims to study the genetic concepts of heredity and evolution in artificial genetic polymers. Since many of the polymerases needed to synthesize XNA polymers are not available commercially, researchers must express and purify these enzymes as recombinant proteins from E. coli. This unit details the steps needed to express, purify, and evaluate the activity of engineered polymerases with altered substrate recognition properties. The protocol requires 6 days to complete and will produce ∼20 mg of pure, nuclease‐free polymerase per liter of E. coli bacterial culture. © 2017 by John Wiley & Sons, Inc.
Lattice Vibration and Polaron Properties of InSb Under Pressure
Authors: Bouarissa N. , Siddiqui S. A. , Boucenna M.
Published: June 2017

The optical phonon modes and polaron properties in InSb at zero and under hydrostatic pressure are investigated using a pseudopotential approach. Our findings are compared to data in the literature, where possible, and found to be in reasonable agreement. The pressure dependence of longitudinal and transverse optical phonon frequencies, electron effective mass, Debye temperature of the longitudinal optical phonon frequency and polaron effective mass has been examined and discussed. All features of interest are found to vary monotonically upon compression. The results regarding polaron properties under pressure may be seen as the first predictions.
Design and Luminescence Chromism of Fused Boron Complexes Having Constant Emission Efficiencies in Solution and in the Amorphous and Crystalline States
Authors: Suenaga Kazumasa , Tanaka Kazuo , Chujo Yoshiki
Published: June 2017

Mechanochromic luminescent molecules often suffer from critical loss of luminescence intensity during phase transitions in the solid state. In this study, we present mechanochromic luminescent molecules that can provide clear color changes with constant emission intensity during phase transitions. It was reported that the class of aggregation‐induced emission (AIE)‐active boron complexes can present intense emission by freezing intramolecular motions. According to this mechanism, we designed a complex with a fused ligand to preserve the enhanced emission in the aggregated state in the AIE during phase transitions between the solution, amorphous, and crystalline states. From optical measurements, it was shown that the synthesized boron complexes present bright emission in various phases. In particular, as we expected, the luminescence color was clearly altered during phase transition, whereas the emission intensity changed only slightly. Finally, we also found that diverse luminescence colors were obtained from each polymorph and for various substituents as induced by the substituent effect. The results in the series of mechanistic studies show that electronic interactions and π–π interactions can modulate the electronic conjugation system of the complexes without causing loss of emission efficiency.
Influence of the production system on the surface properties of influenza A virus particles
Authors: Hämmerling Frank , Pieler Michael M. , Hennig René , Serve Anja , Rapp Erdmann , Wolff Michael W. , Reichl Udo , Hubbuch Jürgen
Published: June 2017

In this study, influenza A/Puerto Rico/8/34 H1N1 virus particles (VP) produced in adherent and suspension Madin Darby canine kidney cells were investigated with a broad analytical toolbox to obtain more information on the VP's surface properties potentially affecting their aggregation behavior. First, differences in aggregation behavior were revealed by VP size distributions obtained via differential centrifugal sedimentation and confirmed by dynamic light scattering. The VP produced in adherent cells showed increased levels of aggregation in a 20 mM NaCl 10 mM Tris‐HCl pH 7.4 low‐salt buffer. This included the formation of multimers (dimers up to pentamers), whereas VP produced in suspension cells displayed no tendency toward aggregate formation. To investigate the cause of these differences in aggregation behavior, the VP samples were compared based on their zeta potential, their surface hydrophobicity, their lipid composition, and the N‐glycosylation of their major VP surface protein hemagglutinin. The zeta potential and the hydrophobicity of the VP produced in the adherent cells was significantly decreased compared to the VP produced in the suspension cells. The lipid composition of both VP systems was approximately identical. The hemagglutinin of the VP produced in adherent cells included more of the larger N‐glycans, whereas the VP produced in suspension cells included more of the smaller N‐glycans. These results indicate that differences in the glycosylation of viral surface proteins should be monitored to characterize VP hydrophobicity and aggregation behavior, and to avoid aggregate formation and product losses in virus purification processes for vaccines and gene therapy.
Sensitivity analysis of the seismic demands of RC moment resisting frames to different aspects of ground motions
Authors: Kiani Jalal , Pezeshk Shahram
Published: June 2017

A weight vector representing the relative importance of various characteristics of ground motions (GMs) and a conditioning intensity measure (IM) are required to be able to use the generalized conditional IM framework for the purpose of GM selection. An inappropriate weight vector may result in the biased distributions of some important characteristics of GMs and, consequently, the bias in the structural responses. This article aims to provide the analyst with the understanding of which properties of GMs are important in capturing the accurate structural responses, to specifically assign a suitable weight to them and to select an appropriate conditioning IM as well. To this end, 4 reinforced concrete buildings, located at the site in which the seismic hazard is dominated by shallow crustal earthquakes, are considered. The findings reveal that the appropriate weight vectors depend on the characteristics of the employed structural systems. In addition, the role played by each IM in capturing the true structural responses changes over different earthquake intensity levels implying that different weight vectors are required over different earthquake levels. Furthermore, this study shows that, even in case of shorter‐duration GMs from shallow events, GM duration should be incorporated in GM selection as it has effects on the peak‐based structural responses in the earthquake levels beyond the level of 2%‐in‐50‐years. Specifically, the findings reveal that in case of shallow events, unlike large magnitude earthquakes, the shorter the duration of GM the more rapid release of energy and, consequently, the larger the peak‐based structural responses.
Detecting genetic association through shortest paths in a bidirected graph
Authors: Ueki Masao , Kawasaki Yoshinori , Tamiya Gen ,   for Alzheimer's Disease Neuroimaging Initiative
Published: June 2017

Genome‐wide association studies (GWASs) commonly use marginal association tests for each single‐nucleotide polymorphism (SNP). Because these tests treat SNPs as independent, their power will be suboptimal for detecting SNPs hidden by linkage disequilibrium (LD). One way to improve power is to use a multiple regression model. However, the large number of SNPs preclude simultaneous fitting with multiple regression, and subset regression is infeasible because of an exorbitant number of candidate subsets. We therefore propose a new method for detecting hidden SNPs having significant yet weak marginal association in a multiple regression model. Our method begins by constructing a bidirected graph locally around each SNP that demonstrates a moderately sized marginal association signal, thefocalSNPs. Vertexes correspond to SNPs, and adjacency between vertexes is defined by an LD measure. Subsequently, the method collects from each graph all shortest paths to the focal SNP. Finally, for each shortest path the method fits a multiple regression model to all the SNPs lying in the path and tests the significance of the regression coefficient corresponding to the terminal SNP in the path. Simulation studies show that the proposed method can detect susceptibility SNPs hidden by LD that go undetected with marginal association testing or with existing multivariate methods. When applied to real GWAS data from the Alzheimer's Disease Neuroimaging Initiative (ADNI), our method detected two groups of SNPs: one in a region containing theapolipoprotein E(APOE) gene, and another in a region close to thesemaphorin 5A(SEMA5A) gene.
The lithologic differences between the third and fourth members of the Eocene Shahejie Formation in the Bohai Bay Basin and the associated climatic evolution
Authors: Wu Liangjun , Wang Fukui , Wang Dehai , Fu Mao , Jia Yuhua
Published: June 2017

The Bohai Bay Basin straddled the Eocene boundary between arid and wet climates in eastern China. The basin was simultaneously affected by both arid and wet climates, and contemporaneous sediments developed under both extremely arid and extremely wet conditions. Data from every well drilled in the oil fields in the Bohai Bay Basin have been used to study the lower fourth member and the upper third member of the Shahejie Formation. The spatial distribution of climate indicators in the lower fourth member of the Shahejie Formation shows that the climate boundary extended from the northern Jizhong Depression to the Bozhong Depression. The portion of the basin to the north of this boundary mostly developed coalbeds, dark mudstone, and oil shale (indicative of a warm and wet climate), whereas the portion of the basin to the south of this boundary mostly developed gypsum, rock salt, and magenta dolomitic mudstone (indicative of a hot and arid climate). During the formation of the upper third member of the Shahejie Formation, the climate boundary shifted southward to the region between the southern part of the Jizhong Depression and the Jiyang Depression. The wet climate zone in the north expanded southward, and the arid climate zone in the south shrank. This shift is evident in the vertical lithologic characteristics of the members that formed before and after this shift in the climate boundary. The lithologic succession in the central part of the basin exhibits significant changes, whereas the lithologic successions in the southern and northern parts of the basin remain homogeneous and stable through time. Therefore, between the formation of the third and fourth members of the Eocene Shahejie Formation, the Bohai Bay Basin experienced a significant climate change. This change directly affected the pattern of the Eocene climate zones in eastern China and is indicative of changes in the paleoclimate zones near the Tropic of Cancer.
Tumor‐Targeting Salmonella typhimurium A1‐R Promotes Tumoricidal CD8+ T Cell Tumor Infiltration and Arrests Growth and Metastasis in a Syngeneic Pancreatic‐Cancer Orthotopic Mouse Model
Authors: Murakami Takashi , Hiroshima Yukihiko , Zhang Yong , Zhao Ming , Kiyuna Tasuku , Hwang Ho Kyoung , Miyake Kentaro , Homma Yuki , Mori Ryutaro , Matsuyama Ryusei , Chishima Takashi , Ichikawa Yasushi , Tanaka Kuniya , Bouvet Michael , Endo Itaru , Hoffman Robert M.
Published: June 2017

The present study determined the effect of the tumor‐targeting strain Salmonella typhimurium A1‐R (S. typhimurium A1‐R) on CD8+ tumor‐infiltrating lymphocytes (TILs) in a syngeneic pancreatic‐cancer orthotopic mouse model. The effect of tumor‐targeting S. typhimurium A1‐R on CD8+ TILs was determined on the Pan02 murine pancreatic‐adenocarcinoma implanted orthotopically in the pancreatic tail of C57BL/6 immunocompromised mice. Three weeks after orthotopic implantation, mice were randomized as follows G1: untreated control group (n = 8); and G2: S. typhimurium A1‐R‐treatment group (n = 8, 1 × 107 colony forming units [CFU]/body, iv, weekly, 3 weeks). On the 22nd day from initial treatment, all mice were sacrificed and tumors were harvested. The tumor‐volume ratio was defined as ratio of tumor volume on the 22nd day relative to the 1st day. The tumor volume ratio was significantly lower in the S. typhimurium A1‐R‐treated group (G2) (3.0 ± 2.8) than the untreated control (G1) (39.9 ± 30.7, P < 0.01). Hematoxylin and easin (H&E) staining on tumor sections was performed to evaluate tumor destruction which was classified according to the Evans grading system and found to be much greater in the S. typhimurium A1‐R‐treated mice (G2). Six mice in G1 had peritoneal dissemination, whereas no mice showed peritoneal dissemination in G2 (P < 0.01). Immunohistochemical staining with anti‐mouse CD8+ antibody was performed in order to detect TILs determined by calculating the average number of CD8+ cells in three high power fields (200×) in the treated and untreated tumors. The TIL score was significantly higher in G2 (133.5 ± 32.2) than G1 (45.1 ± 19.4, P < 0.001). The present study demonstrates that S. typhimurium A1‐R promotes CD8+ T cell infiltration and inhibition of tumor growth and metastasis. J. Cell. Biochem. 119: 634–639, 2018. © 2017 Wiley Periodicals, Inc.
Gas adsorption in Mg‐porphyrin‐based porous organic frameworks: A computational simulation by first‐principles derived force field
Authors: Pang Yujia , Li Wenliang , Zhang Jingping
Published: June 2017

A novel type of porous organic frameworks, based on Mg‐porphyrin, with diamond‐like topology, named POF‐Mgs is computationally designed, and the gas uptakes of CO2, H2, N2, and H2O in POF‐Mgs are investigated by Grand canonical Monte Carlo simulations based on first‐principles derived force fields (FF). The FF, which describes the interactions between POF‐Mgs and gases, are fitted by dispersion corrected double‐hybrid density functional theory, B2PLYP‐D3. The good agreement between the obtained FF and the first‐principle energies data confirms the reliability of the FF. Furthermore our simulation shows the presence of a small amount of H2O (≤ 0.01 kPa) does not much affect the adsorption quantity of CO2, but the presence of higher partial pressure of H2O (≥ 0.1 kPa) results in the CO2 adsorption decrease significantly. The good performance of POF‐Mgs in the simulation inspires us to design novel porous materials experimentally for gas adsorption and purification. © 2017 Wiley Periodicals, Inc.
MicroRNA‐mediated drug resistance in ovarian cancer
Authors: Mihanfar Aynaz , Fattahi Amir , Nejabati Hamid Reza
Published: June 2017

The development of intrinsic or acquired resistance to chemotherapeutic agents used in the treatment of various human cancers is a major obstacle for the successful abolishment of cancer. The accumulated efforts in the understanding the exact mechanisms of development of multidrug resistance (MDR) have led to the introduction of several unique and common mechanisms. Recent studies demonstrate the regulatory role of small noncoding RNA or miRNA in the several parts of cancer biology. Practically all aspects of cell physiology under normal and disease conditions are reported to be controlled by miRNAs. In this review, we discuss how the miRNA profile is changed upon MDR development and the pivotal regulatory role played by miRNAs in overcoming resistance to chemotherapeutic agents. It is hoped that further studies will support the use of these differentially expressed miRNAs as prognostic and predictive markers, as well as novel therapeutic targets to overcome resistance in ovarian cancer.
Importance of endothelial dysfunction biomarkers in patients with Crimean‐Congo hemorrhagic fever
Authors: Arslan Mustafa , Yilmaz Gürdal , Mentese Ahmet , Yilmaz Hülya , Karahan Süleyman C. , Koksal Iftihar
Published: June 2017

The pathogenesis of the Crimean‐Congo hemorrhagic fever (CCHF) and the cause of the hemorrhage are not yet fully understood. However, the endothelium plays a key role in the pathogenesis. The purpose of this study was to investigate endothelial dysfunction markers (asymmetrical dimethyl arginine [ADMA], endothelin 1[ET‐1], thrombomodulin [TM], von Willebrand factor [vWf], and intercellular adhesion molecule [ICAM‐1]) in serum in patients with CCHF and their associations with hemorrhage. Seventy‐three patients with CCHF were included in the study. All patients’ endothelial dysfunction markers were studied using routine biochemical and hematological tests. The data obtained were then subjected to statistical analysis. Statistically significant differences were determined between the patients and healthy control groups at time of presentation to hospital in terms of ADMA (P < 0.001), ET‐1 (P < 0.001), TM (P = 0.039), vWf (P < 0.001), and ICAM‐1 (P < 0.001) levels. Only the differences in TM and vWf were significant between the hemorrhagic and non‐hemorrhagic groups (P < 0.05). Both serum ADMA and TM levels were significantly higher in the hemorrhage and non‐hemorrhage CCHF groups on the 5th day compared to the 1st day (P < 0.05). Levels of endothelial dysfunction markers in CCHF vary in proportion to the damage occurring in the endothelium. ADMA and TM levels were lower in periods with mild endothelial injury. They were increased in line with severity endothelial injury. They may be an early marker in showing hemorrhage. Elevation in ADMA levels and low nitric oxide levels lead to endothelial injury and hemorrhage. Soluble TM that entered the circulation in line with the increased endothelial injury in hemorrhagic patients has been compromised the coagulation cascade.
d:x reflectance measurement for curved surface with integrating sphere
Authors: Yu Hsueh‐Ling , Young Richard , Liu Wen‐Chun , Hsiao Chin‐Chai
Published: June 2017

Ambient contrast ratio (ACR) is a useful parameter to evaluate the quality of displays when used under diffuse lighting conditions. The methodology recommended by most documentary standards calculates the ACR of the display from d:x reflectance. Reflectance measurement of flat surfaces typically employs an integrating sphere and a flat white reference plate. However, the shape difference between the flat white standard and test curved sample causes changes to the amount of light illuminating their surfaces and thus gives measurement errors. Especially for concave test surfaces, the error is significant when the sample has small radius of curvature. To increase the measurement accuracy, this paper derives the correction factor to compensate the effect caused by shape difference between the reference plate and test curved sample. The associated uncertainty analysis is also discussed in this paper.
Characterizing the detection threshold for optical imaging in surgical oncology
Authors: Prince Andrew C. , Jani Aditi , Korb Melissa , Tipirneni Kiranya E. , Kasten Benjamin B. , Rosenthal Eben L. , Warram Jason M.
Published: June 2017

Background and Objectives

Optical imaging to guide cancer resections is rapidly transitioning into the operating room. However, the sensitivity of this technique to detect subclinical disease is yet characterized. The purpose of this study was to determine the minimum range of cancer cells that can be detected by antibody‐based fluorescence imaging.

Methods

2LMP (breast), COLO‐205 (colon), MiaPaca‐2 (pancreas), and SCC‐1 (head and neck) cells incubated in vitro with cetuximab‐IRDye800CW (dose range 8.6‐86 nM) were implanted subcutaneously in mice (n = 3 mice, 5 tumors/mouse). Following incubation with 8.6 × 10−2 µM of cetuximab‐IRDye800CW in vitro, serial dilutions of each cell type (1 × 103–1 × 106) were implanted subcutaneously (n = 3, 5 tumors/mouse). Tumors were imaged with Pearl Impulse and Xenogen IVIS 100 imaging systems. Scatchard analysis was performed to determine receptor density and kinetics for each cell line.

Results

Under conditions of minimal cetuximab‐IRDye800CW exposure to low cellular quantity, closed‐field fluorescence imaging theoretically detected a minimum of 4.2 × 104‐9.5 × 104 2LMP cells, 1.9 × 105‐4.5 × 105 MiaPaca‐2 cells, and 2.4 × 104‐6.7 × 104 SCC‐1 cells; COLO‐205 cells could not be identified. Higher EGFR‐mediated uptake of cetuximab correlated with sensitivity of detection.

Conclusion

This study supports the clinical utility of cetuximab‐IRDye800CW to sensitively localize subclinical disease in the surgical setting.
Prescribed fire influences habitat selection of female eastern wild turkeys
Authors: Yeldell Nathan A. , Cohen Bradley S. , Prebyl Thomas J. , Collier Bret A. , Chamberlain Michael J.
Published: June 2017

Prescribed fire is widely used in southeastern pine (Pinus spp.) forests to maintain desirable forest conditions and provide early successional vegetation. However, it is unclear how fires applied just prior to and during the reproductive cycle of ground nesting Galliformes influence resource selection. We examined the short‐term influence of prescribed fire on habitat selection of female eastern wild turkeys (Meleagris gallopavo silvestris) throughout their reproductive cycle (Feb−Aug) at Kisatchie National Forest in west‐central Louisiana, USA during 2014 and 2015. Kisatchie was dominated (>60%) by pine stands managed with prescribed fire at a frequent (i.e., 1–3 yr) return interval. We captured 46 females and equipped them with backpack‐style global positioning system (GPS) transmitters programmed to collect relocation data hourly from 0600 to 2000 each day. We used distance‐based analysis to estimate selection or avoidance of vegetation communities relative to reproductive phenology of individual females. Hardwood and mixed‐pine hardwood vegetation communities were selected for before and after reproductive efforts; hardwood stands were avoided during brooding. While laying their first clutch of the reproductive period, females selected mature pines burned 0–5 months prior. Females avoided mature pine stands 2 growing seasons post‐burn prior to initiating their first nests. Females avoided mature pine stands 3 growing seasons post‐burn when brooding. Turkeys did not select for pine stands that had experienced ≥3 growing seasons post‐burn during any reproductive period, and may avoid these stands during pre‐nesting and brooding. Frequent fire return intervals maintain vegetation communities that females select at some point during the reproductive season in pine‐dominated landscapes. © 2017 The Wildlife Society.
Trends in sleep studies performed for Medicare beneficiaries
Authors: Chiao Whitney , Durr Megan L.
Published: June 2017

Objectives/Hypothesis

To quantify trends and characteristics of sleep studies performed for Medicare beneficiaries in the United States.

Study Design

Retrospective longitudinal study of the Centers for Medicare and Medicaid Services' Part B National Summary Data and Medicare Provider Utilization and Payment Data from 2000 to 2014.

Methods

Sleep study data were analyzed according to type of study performed, total expenditure amount, provider specialty, and geographic location.

Results

In 2014, 845,569 sleep studies were completed by 1.4% of Medicare beneficiaries for a total of $189 million. Since 2010, annual expenditures for sleep studies have declined, whereas the number of studies performed has increased by 9.1%. In 2014, polysomnography, split‐night polysomnography, and unattended home sleep studies accounted for 40%, 48%, and 12%, respectively, of total sleep studies. This represents a dramatic growth in the number of unattended sleep studies performed since 2000, when they represented only 0.9%. Pulmonologists, independent diagnostic testing facilities, and neurologists are the top specialties that bill for sleep studies. Sleep medicine is a growing specialty and ranked fifth among providers, whereas otolaryngologists ranked eighth.

Conclusions

The healthcare burden of administering sleep studies is substantial, although the annual cost is declining. Unattended sleep studies contribute to decreasing costs and should be considered for patients who meet the correct indications.

Level of Evidence

4. Laryngoscope, 127:2891–2896, 2017
The Influence of Oxygen Atoms on Conformation and π–π Stacking of Ladder‐Type Donor‐Based Polymers and Their Photovoltaic Properties
Authors: Qin Tong , Zang Yue , Bai Wei‐Yun , Yao Kai , Xu Yun‐Xiang
Published: June 2017

A novel ladder‐type donor pyran‐bridged indacenodithiophene (IDTP) is developed by introducing two oxygen atoms into indacenodithiophene unit. IDTP possesses a twisted backbone and leads to facially asymmetric arrangement of side chains, resulting in enhanced local π–π stacking of according polymer poly[(5,5,11,11‐tetrakis(4‐octylphenyl)‐5,11‐dihydrothieno[2′,3′:5,6]pyrano[3,4‐g]thieno[3,2‐c]isochromene)‐alt‐4,7‐(5‐fluoro‐2,1,3‐benzothiadiazole)] (PIDTP)‐FBT, which shows extended absorption range. Moreover, oxygen atoms render deeper highest occupied molecular orbital (HOMO) levels of poly[indacenodithiophene‐alt‐4,7‐(5‐fluoro‐2,1,3‐benzothiadiazole)] (PIDTP)‐FBT compared with PIDT‐FBT, therefore bringing a higher open‐circuit voltage (Voc).
Phase‐Separable Polyisobutylene Palladium‐PEPPSI Precatalysts: Synthesis and Application in Buchwald–Hartwig Amination
Authors: Balogh Janos , Hlil Antsar Rih , El‐Zoghbi Ibrahim , Rafique Muhammad Ghufran , Chouikhi Dalila , Al‐Hashimi Mohammed , Bazzi Hassan S.
Published: June 2017

This paper reports the efficient synthesis of the first class of polyisobutylene(PIB)‐supported palladium‐PEPPSI precatalyst (PEPPSI = pyridine‐enhanced precatalyst preparation, stabilization, and initiation). The new complexes are employed in Buchwald–Hartwig amination of aryl chlorides and are found to be reasonably active in the titled cross‐coupling reaction. The supported catalysts are tested in polar (1,4‐dioxane and 1,2‐dimethoxyethane) as well as in aliphatic reaction media (toluene and n‐heptane) and display superior activity in the highly lipophilic solvent (n‐heptane). The catalytic efficacy of PIB‐Pd‐PEPPSI precatalyst is measured to be comparable to its nonsupported analog. Pd‐leaching is determined by inductively coupled plasma mass spectrometry (ICP‐MS) after a simple liquid/liquid extraction and is found to be 2 ppb in the product phase, translating into a recovery of ≈99.8% of the palladium.
On‐line reaction monitoring by mass spectrometry, modern approaches for the analysis of chemical reactions
Authors: Ray Andrew , Bristow Tony , Whitmore Chris , Mosely Jackie
Published: June 2017

The application of on‐line mass spectrometry for direct analysis of chemical and other types of process continues to grow in importance and impact. The ability of the technique to characterize many aspects of a chemical reaction such as product and impurity formation, along with reactant consumption in a single experiment is key to its adoption and development. Innovations in ionization techniques and mass spectrometry instrumentation are enabling this adoption. An increasing range of ambient ionization techniques make on‐line mass spectrometry applicable to a large range of chemistries. The academic development and commercialization of small footprint portable/transportable mass spectrometers is providing technology that can be positioned with any process under investigation. These developments, coupled with research into new ways of sampling representatively from both the condensed and gaseous phases, are positioning mass spectrometry as an essential technology for on‐line process optimization, understanding and intelligent control. It is recognized that quantitative capability of mass spectrometry in this application can cause some resistance to its adoption, but research activities to tackle this limitation are on‐going.
Finite element modelling of lamb waves propagation in 2D plates and thin sheets for damage detection
Authors: Nirbhay M. , Dixit A. , Misra R.K.
Published: June 2017

Structural health monitoring is an evolving technology applied to identify, locate and quantify severity of damages in structures before failure. Lamb waves have become a keen interest for inspection since they can be used to monitor a large area from one single location. The objective of this research is to simulate lamb wave response using finite element method and its application to crack detection and identification in thin metallic engineering structures. Two types of specimen i. e. two‐dimensional aluminium plate and thin aluminium sheets are simulated using commercially available finite element package ABAQUS. Initially phase velocity and group velocity dispersion curve are plotted for aluminium material. Thereafter simulation of individual specimens with cracks and without cracks is performed. Simulation results were compared and validated with actual results and were found to be in reasonably good agreement. This is certainly done by employing group velocity and time of flight for the distance travelled between the monitoring point and crack position. Assessment of lamb waves sensitivity to various sizes and shapes of cracks like rectangular and circular are also investigated and its effect on the structure is discussed in detail.
Digital modelling of the galvanic corrosion behaviour of a self–piercing riveted AZ31 ‐ AA5083 hybrid joint
Authors: Silva E. L. , Höche D. , Bouali A. C. , Serdechnova M. , Sesenes R. L. , Scholz C. S. , Zheludkevich M. L.
Published: June 2017

This study focuses on the corrosion phenomena occurring between aluminium AA5083 and AZ31 magnesium sheets, joined with a coated steel self‐piercing rivet, by punch rivet technology. These assemblies were studied by immersion tests and scanning vibrating electrode technique (SVET) in sodium chloride solutions, in order to evaluate the effects of joint geometry on corrosion resistance. The observed results were also used for validation of transient finite element method (FEM) simulations. A fully coupled continuum model was used to compute the evolution of electrochemically and chemically induced corrosion attack, formation of corrosion products and their influence on the overall system kinetics. Additionally, X‐ray diffraction (XRD) analysis of the corrosion products provided evidence for the formation of layered double hydroxides (LDH), which is in accordance with the model outputs. The current study targets the optimization of joint setup for corrosion resistance. The suitability of corrosion simulation for the AZ31‐AA5083‐Almac ternary galvanic system is shown alongside. The developed modelling approach represents a step forward in terms of digital service‐life assessment of multi‐material joints.
Thermal cycling and isothermal oxidation behavior of quadruple EB‐PVD thermal barrier coatings
Authors: Bobzin K. , Brögelmann T. , Kalscheuer C. , Yildirim B. , Welters M.
Published: June 2017

Increase of energy efficiency by increasing the turbine inlet temperature is the main driving force for further investigations regarding new thermal barrier coating materials. Today, thermal barrier coatings consisting of yttria stabilized zirconia are state of the art. In this study, thermal barrier coatings consisting of 7 weight percent yttria stabilized zirconia (7YSZ) and pyrochlore lanthanum zirconate (La2Zr2O7) were deposited by electron beam physical vapor deposition. Regarding thermal cycling and isothermal oxidation behavior different layer architectures such as mono‐, double‐ and quadruple ceramic layers were investigated. The thermal shock behavior was examined by thermocycle tests at temperatures in the range between T = 50 °C ‐1,150 °C. Additionally, the isothermal oxidation behavior at a temperature of T = 1,150 °C with dwell times of t= 50 h and t = 100 h was studied in the present work. The conducted research concerning the behavior of various thermal barrier coating systems under thermal cycle and isothermal load highlights the potential of multilayer thermal barrier coatings for operating in high temperature areas.
Randschichteigenspannungen durch mechanisches Schleifen bei hochfesten Federstählen
Authors: Thomisch M. , Kalhöfer E. , Kley M. , Schmid H. , Savsek O.
Published: June 2017

Ein häufiger Vertreter für ölschlussvergütete Federstähle ist der Werkstoff 54SiCr6 (1.7102). Um eine möglichst große Anlagefläche der daraus gefertigten Federn an die angrenzende Auflagefläche zu erreichen, werden die Federenden mechanisch plan geschliffen. Durch alle Bearbeitungsprozesse (Winden, Schleifen und Kugel‐ strahlen) werden die teileweise bereits vorhandenen Eigenspannungen durch zusätzlich eingebrachte Zug‐ oder Druckeigenspannungen beeinflusst und in Betrag und ggf. ihrer Richtung verändert. Die Kenntnis dieser resultierenden Eigenspannung ist bereits in der Entwurfsphase der Feder von Bedeutung, da diese mit den auftretenden Betriebsbelastungen überlagert werden müssen. Das Schleifen an sich hat einen deutlichen Einfluss auf die Höhe der Eigenspannungen im Bauteil. Bezüglich der Gestaltung des Schleifprozesses sind die Höhe und die Richtung der Eigenspannungen stark von der Wahl der Schleifparameter abhängig. So lässt sich bestätigen, dass Schleifvorgänge mit dominierendem thermischem Einfluss tendenziell zu Zugspannungen führen; dominierende mechanische Einflüsse spiegeln sich in Druckspannungen wieder. Die Untersuchung zeigt, dass die Eigenspannungen sowohl von der Zustellung je Hub, der wahlweisen Zustellung im Gleich‐ oder Gegenlauf und dem optionalen Einsatz von Kühlschmierstoff, abhängen. Aussagen zur Überlagerung der Eigenspannungen durch Schleifen mit den Eigenspannungen durch Umformen und Kugelstrahlen sind pauschal nicht möglich.
Ensemble Architecture for Prediction of Enzyme‐ligand Binding Residues Using Evolutionary Information
Authors: Pai Priyadarshini P. , Dattatreya Rohit Kadam , Mondal Sukanta
Published: June 2017

Enzyme interactions with ligands are crucial for various biochemical reactions governing life. Over many years attempts to identify these residues for biotechnological manipulations have been made using experimental and computational techniques. The computational approaches have gathered impetus with the accruing availability of sequence and structure information, broadly classified into template‐based and de novo methods. One of the predominant de novo methods using sequence information involves application of biological properties for supervised machine learning. Here, we propose a support vector machines‐based ensemble for prediction of protein‐ligand interacting residues using one of the most important discriminative contributing properties in the interacting residue neighbourhood, i. e., evolutionary information in the form of position‐specific‐ scoring matrix (PSSM). The study has been performed on a non‐redundant dataset comprising of 9269 interacting and 91773 non‐interacting residues for prediction model generation and further evaluation. Of the various PSSM‐based models explored, the proposed method named ROBBY (pRediction Of Biologically relevant small molecule Binding residues on enzYmes) shows an accuracy of 84.0 %, Matthews Correlation Coefficient of 0.343 and F‐measure of 39.0 % on 78 test enzymes. Further, scope of adding domain knowledge such as pocket information has also been investigated; results showed significant enhancement in method precision. Findings are hoped to boost the reliability of small‐molecule ligand interaction prediction for enzyme applications and drug design.
Tangential fluid flow within 3D narrow fissures: Conservative velocity fields on associated triangulations and transport processes
Authors: Morales Fernando A. , Ramírez Jorge M.
Published: June 2017

For a fissured medium with uncertainty in the knowledge of fractures' geometry, a conservative tangential flow field is constructed, which is consistent with the physics of stationary fluid flow in porous media and an interpolated geometry of the cracks. The flow field permits computing preferential fluid flow directions of the medium, rates of mechanical energy dissipations, and a stochastic matrix modeling stream lines and fluid mass transportation, for the analysis of solute/contaminant mass advection‐diffusion as well as drainage times.
Impact of prior distributions and central tendency measures on Bayesian intravoxel incoherent motion model fitting
Authors: Gustafsson Oscar , Montelius Mikael , Starck Göran , Ljungberg Maria
Published: June 2017

Purpose

Bayesian model fitting has been proposed as a robust alternative for intravoxel incoherent motion (IVIM) model‐fitting parameter estimation. However, consensus regarding choice of prior distribution and posterior distribution central tendency measure is needed. The aim of this study was to compare the quality of IVIM parameter estimates produced by different prior distributions and central tendency measures, and to gain knowledge about the effect of these choices.

Methods

Three prior distributions (uniform, reciprocal, and lognormal) and two measures of central tendency (mean and mode) found in the literature were studied using simulations and in vivo data from a tumor mouse model.

Results

Simulations showed that the uniform and lognormal priors were superior to the reciprocal prior, especially for the parameters D and f and clinically relevant SNR levels. The choice of central tendency measure had less effect on the results, but had some effects on estimation bias. Results based on simulations and in vivo data agreed well, indicating high validity of the simulations.

Conclusions

Choice of prior distribution and central tendency measure affects the results of Bayesian IVIM parameter estimates. This must be considered when comparing results from different studies. The best overall quality of IVIM parameter estimates was obtained using the lognormal prior. Magn Reson Med 79:1674–1683, 2018. © 2017 International Society for Magnetic Resonance in Medicine.
Polymeric microspheres: a delivery system for osteogenic differentiation
Authors: Patel Rajkumar , Patel Madhumita , Kwak Jeonghun , Iyer Arun K. , Karpoormath Rajshekhar , Desai Shrojal , Rarh Vimal
Published: June 2017

Advanced drug delivery systems employing controlled release technology are being developed to address many of the difficulties associated with traditional methods of drug administration. Controlled release technology involves the use of devices such as polymer‐based disks, rods, pellets, or microspheres (MSs) that encapsulate drugs, genes, cytokines, and growth factors and release them in specific location within the body in a controlled fashion, for relatively long periods of time. Among these, microencapsulation is one of the core technologies used in polymer‐based drug delivery systems. In this regard, MS serves as microcarriers for sustain drug release facilitating their use for invasive or minimally invasive treatment. MS has significant potential for the application in bone repair, intra‐articular treatment of osteoarthritis, and biological bone growth. The present review compiles the recent advances in polymeric MS for application in bone and cartilage regeneration. Copyright © 2017 John Wiley & Sons, Ltd.