bluuebunny/crossref_metadata_2025 huggingface dataset:
Removal of N‐Terminal Blocking Groups from Proteins
Authors: Leone Joseph W. , Hampton Brian , Fowler Elizabeth , Moyer Mary , Krishna Radha G. , Chin Christopher C.Q.
Published: February 2011

Two enzymatic methods commonly used in N‐terminal sequence analysis of blocked proteins are presented: one uses pyroglutamate aminopeptidase for Nα‐pyrrolidone carboxyl‐proteins in solution or blotted onto a membrane, and the other uses acylaminoacyl‐peptide hydrolase for Nα‐acyl‐proteins blocked with other acyl groups. A Support Protocol describes a colorimetric assay for pyroglutamate aminopeptidase activity. Sequencing with acylaminoacyl‐peptide hydrolase must include fragmentation of the protein before unblocking, so procedures are provided for chemically blocking newly generated peptides with either succinic anhydride or phenylisothiocyanate/performic acid. The hydrolase is then applied to the total mixture of peptides, only one of which, the acylated N‐terminal peptide, should be a substrate for hydrolase. After incubation, the mixture of peptides is subjected to sequence analysis. Curr. Protoc. Protein Sci. 63:11.7.1‐11.7.20. © 2011 by John Wiley & Sons, Inc.
Analysis of Protein S‐Nitrosylation
Authors: Schonhoff Christopher M. , Benhar Moran
Published: February 2011

S‐Nitrosylation, the redox‐based modification of cysteine thiol side chains by nitric oxide, is a dynamic and reversible post‐translational modification of proteins that subserves many important cellular functions. Analysis of protein S‐nitrosylation is often challenging due to methodological limitations and the effects of various chemical and physical parameters. Despite these technical challenges, a growing number of useful methods are now available to analyze protein S‐nitrosylation. In this unit, several important methods to measure protein S‐nitrosylation and denitrosylation are discussed and evaluated. Recommendations are given regarding the potential and the applicability of the methods discussed. Curr. Protoc. Protein Sci. 63:14.6.1‐14.6.21. © 2011 by John Wiley & Sons, Inc.
Pilot study to assess the frequency of fibromyalgia, depression, and sleep disorders in patients with granulomatosis with polyangiitis (Wegener's)
Authors: Hajj‐Ali Rula A. , Wilke William S. , Calabrese Leonard H. , Hoffman Gary S. , Liu Xiaobo , Bena James , Clark Tiffany , Langford Carol A.
Published: February 2011

Objective

To assess the frequency of fibromyalgia syndrome (FMS), depression, and sleep disorders in patients with granulomatosis with polyangiitis (Wegener's) (GPA).

Methods

The London Fibromyalgia Epidemiologic Study Screening Questionnaire (LFESSQ), Symptom Intensity Scale, Epworth Sleepiness Scale (ESS), and the Brief Patient Health Questionnaire‐9 (BPHQ‐9) were administered prospectively to patients who met the American College of Rheumatology criteria for GPA. Fatigue was captured quantitatively by the fatigue visual analog scale (VAS) and qualitatively by the LFESSQ fatigue questionnaire. Disease activity and damage were captured by using the Birmingham Vasculitis Activity Score for GPA (BVAS/GPA) and the Vasculitis Damage Index (VDI). Frequency of FMS and depression in GPA was compared with the general population.

Results

Patients with GPA have significantly greater frequency of FMS (LFESSQ 23.6 versus 13; P = 0.02) and depression (22% versus 7.6%; P < 0.001) than the general population. Twenty‐nine percent of GPA patients had sleep abnormalities according to ESS scores of ≥10; 76.4% reported fatigue and 49.1% indicated that fatigue significantly limited their activities. There was no correlation between BPHQ‐9, ESS, LFESSQ, fatigue VAS, and VDI, BVAS/GPA, or disease duration. There was a strong correlation between fatigue VAS and BPHQ‐9 (r = 0.73; 95% confidence interval [95% CI] 0.54, 0.92). The correlation between fatigue VAS and ESS was significant but not as strong as with the BPHQ‐9 (r = 0.36; 95% CI 0.10, 0.62).

Conclusion

FMS and depression occur more often in GPA compared with the general population. The association is not related to disease activity, damage, or disease duration. Fatigue is very common and significantly limits normal daily activities. Depression and sleep disorders contribute to fatigue in GPA patients.
Modifiable Sulfur Tethers as Directing Groups for Aromatic CH Acetoxylation Reactions
Authors: Richter Heinrich , Beckendorf Stephan , Mancheño Olga García
Published: February 2011

A designed new class of modifiable sulfur tethers for aromatic CH bond functionalizations is presented. As a model, the palladium‐catalyzed directed acetoxylation reaction was studied. The more challenging sulfoxide tethers were the most effective in this transformation, showing a broad functionality tolerance, high S oxido‐redox stability and no catalyst poisoning. Preliminary mechanistic studies indicate that the higher reactivity and selectivity shown by the sulfoxide tethers vs. the corresponding sulfones can be attributed to an extra coordination of the sulfoxide S atom to the catalyst. The utility of the presented methodology to generate structurally interesting aromatic derivatives by a subsequent modification of the S‐tether is also exemplified.
Methods for estimating missing human skeletal element osteometric dimensions employed in the revised fully technique for estimating stature
Authors: Auerbach Benjamin M.
Published: February 2011

One of the greatest limitations to the application of the revised Fully anatomical stature estimation method is the inability to measure some of the skeletal elements required in its calculation. These element dimensions cannot be obtained due to taphonomic factors, incomplete excavation, or disease processes, and result in missing data. This study examines methods of imputing these missing dimensions using observable Fully measurements from the skeleton and the accuracy of incorporating these missing element estimations into anatomical stature reconstruction. These are further assessed against stature estimations obtained from mathematical regression formulae for the lower limb bones (femur and tibia). Two thousand seven hundred and seventeen North and South American indigenous skeletons were measured, and subsets of these with observable Fully dimensions were used to simulate missing elements and create estimation methods and equations. Comparisons were made directly between anatomically reconstructed statures and mathematically derived statures, as well as with anatomically derived statures with imputed missing dimensions. These analyses demonstrate that, while mathematical stature estimations are more accurate, anatomical statures incorporating missing dimensions are not appreciably less accurate and are more precise. The anatomical stature estimation method using imputed missing dimensions is supported. Missing element estimation, however, is limited to the vertebral column (only when lumbar vertebrae are present) and to talocalcaneal height (only when femora and tibiae are present). Crania, entire vertebral columns, and femoral or tibial lengths cannot be reliably estimated. Further discussion of the applicability of these methods is discussed. Am J Phys Anthropol, 2011. © 2011 Wiley‐Liss, Inc.
Moleküle und biologische Mechanismen des Süß‐ und Umamigeschmacks
Authors: Behrens Maik , Meyerhof Wolfgang , Hellfritsch Caroline , Hofmann Thomas
Published: February 2011

Unsere Wertschätzung für Nahrungsmittel ist weitgehend auf die Auslösung der Geschmacksempfindungen “süß” und “umami” zurückzuführen. Mit einem besonderen Schwerpunkt auf Naturstoffen wird dieser Aufsatz einen Überblick über jene Stoffe geben, die die Geschmackseindrücke “süß” oder “umami” hervorrufen und modulieren. Es wird diskutiert, wie die Wechselwirkung dieser Moleküle mit dem oralen Süß‐ oder Umamigeschmacksrezeptor die Rezeptorzellen anregt, Neurotransmitter abzusondern, um neurale Aktivität hervorzurufen, die an die Großhirnrinde weitergeleitet wird und süßen bzw. umami Geschmack übermittelt. Neue Befunde zeigen auch, dass süßer Geschmack für die Homöostase des Energiehaushalts metabolisch relevant und mit dem appetitiven ingestiven Verhalten verknüpft ist.
Review of numerical modeling of pasta drying, a closer look into model parameters
Authors: Veladat Reza , Zokaee Ashtiani Farzin , Rahmani Mohammad , Miri Taghi
Published: February 2011

In the pasta production process, drying is an energy‐intensive stage which affects many of the final product properties. However, the drying process for pasta is only understood on an empirical basis. The availability of a reliable mathematical model for drying can provide a better understanding of how the different parameters affect the food quality of dried pasta. Models can also allow optimization of the drying process design and/or operation and associated cost reductions. Drying includes simultaneous heat and mass transfer phenomena, and development of a model requires a complex system of coupled nonlinear partial differential equations. Furthermore, models usually include several parameters with unknown values which are not easy to estimate, this is especially true for food materials such as pasta. This work is a review of the different aspects of mathematical modeling of pasta drying, methods and correlations for the prediction of model parameters, as well as recent trends in numerical solution. The application of computational fluid dynamics approaches is discussed. This paper includes a discussion on prediction of the pasta quality indices obtained from the numerical modeling. Copyright © 2011 Curtin University of Technology and John Wiley & Sons, Ltd.
Compatible polycarbonate/polyamide 6,6 blends with fibrillar morphology
Authors: Granado Ainhoa , Eguiazábal Jose Ignacio , Nazábal Jon
Published: February 2011

Blends of bisphenol A polycarbonate (PC) and polyamide 6,6 (PA6,6) were prepared directly during the plasticization step of an injection molding process in an attempt to attain both (i) the reinforcement of the blends through fibrillar morphology, and (ii) an adequate compatibilization despite the short processing procedure used. Differential scanning calorimetry and dynamic‐mechanical analysis indicated that the blends were made up of a PC‐rich phase where some PA6,6 was present and, ruling out a possible degradation, of an almost pure PA6,6‐phase. The cryogenically fractured surfaces observed by scanning electron microscopy showed both rather fine particles and larger particles with occluded subparticles. This complex morphology indicates low interphase tension and, therefore, compatibilization, which can be attributed to the presence of PA6,6 in the two phases of the blends. The values of Young's modulus, determined by means of tensile tests, were always synergistic and, in the case of the 25/75 blend, the modulus was even higher than those of any of the two pure components. It appears this could be due to both the highly fibrillar morphology of the dispersed phase, and the significant decrease observed in specific volume. The blends remained ductile throughout the full composition range, which also indicates compatibilization. © 2011 Wiley Periodicals, Inc. J Appl Polym Sci, 2011
Vibrational dynamics and heat capacity of polychloroprene
Authors: Gupta Archana , Agarwal Parag , Choudhary Neetu , Tandon Poonam , Gupta V. D.
Published: February 2011

Normal modes and their dispersion have been obtained for polychloroprene in the trans form using Wilson's G F matrix method as modified by Higg's for an infinite polymeric chain. Urey Bradley force field has been used. Several new assignments, which are missing in earlier work, are reported. The assignments of lower frequency modes have been confirmed using inelastic neutron scattering data. The characteristic features of dispersion curves have been explained. Variation of heat capacity as a function of temperature has been predicted. © 2011 Wiley Periodicals, Inc. J Appl Polym Sci, 2011
Synthesis and characterization of PVP/LiCoO2 nanofibers by electrospinning route
Authors: Chen Lin‐Jer , Liao Jiunn‐Der , Chuang Yu‐Ju , Hsu Kuo‐Chin , Chiang Yi‐Fang , Fu Yaw‐Shyan
Published: February 2011

We have successfully prepared PVP/LiCoO2 nanofibers using an electrospinning route. These fibers were composed of very small crystalline grains uniformly linked with an average size. After annealing of the above precursor fibers at 700°C for 12 h, LiCoO2 nanofibers with 95 nm in diameter were composed of crystalline nanoparticles were successfully obtained. The morphology, crystal structure, and particle size of fibers has been characterized by scanning electron microscopy (SEM), energy dispersive spectrometer (EDS), X‐ray diffraction (XRD). The viscosities of solutions were measured with a LVDV Brookfield viscometer. Experimental results showed that the LiCoO2 with good crystalline and uniform diameter were obtained. © 2011 Wiley Periodicals, Inc. J Appl Polym Sci, 2011
Performance evaluation of ultra‐rapid‐hardening roller‐compacted concrete with styrene butadiene latex
Authors: Won Jong‐Pil , Kim Joon‐Mo , Lee Su‐Jin , Lee Sang‐Woo , Park Sung‐Ki
Published: February 2011

This study was conducted to evaluate the performance of rapid‐hardening roller‐compacted concrete containing styrene butadiene latex. This material has no slump and is compacted with a roller after being poured. Volume reduction is not a concern and the material has a high initial strength due to the high pressure applied. Latex improves the durability of ultra‐rapid‐hardening cement composites. This study evaluated the performance of an optimum mixture (L) and a mixture with no styrene butadiene latex (NL), which had almost the same workability as the optimum mixture. The L mixture exhibited better performance than the NL mixture in terms of bond strength and chloride ion permeability, as well as resistance to abrasion, repeated freezing and thawing, and scaling. © 2011 Wiley Periodicals, Inc. J Appl Polym Sci, 2011
Examining the effect of mercerization process applied under different conditions via the degree of whiteness and color efficiency
Authors: Gemci Remzi , Çebiçci Cafer
Published: February 2011

In this study, 100% cotton woven fabrics having three different patterns are mercerized by chained mercerizing machine. The temperature is kept at 60°C for all applications. Application types and process period are the variables of this experiment. The effects of mercerization process applied on different conditions are examined in terms of color efficiency and degree of whiteness. Fabrics with different patterns are also compared with each other to understand whether fabric patterns are effective in whiteness and color efficiency. © 2011 Wiley Periodicals, Inc. J Appl Polym Sci, 2011
Grafting of telechelic poly(lactic‐co‐glycolic acid) onto O2 plasma‐treated polypropylene flakes
Authors: Ren Jing , Hua Xiaoqing , Zhang Tianzhu , Zhang Zhigang , Ji Zhenling , Gu Ning
Published: February 2011

In this work, we described a facile approach to preparing polypropylene (PP) surface functionalized with telechelic poly(lactic‐co‐glycolic acid) (HO‐PLGA‐COOH). The PP flakes were first treated with oxygen plasma and then grafted with different molecular weight PLGA (Mw = 50, 100, and 300 K) in dry dichloromethane solution with the addition of phosphorus pentachloride (PCl5). The attenuated total reflectance‐Fourier transform infrared (ATR–FTIR) spectroscopy measurements were used to characterize the composition of the PP surface. The appearance of 1756 cm−1 for carbonyl (CO) stretching and 1090 cm−1 for COC and the morphologies observations by atomic force microscopy show that PLGA graft covered the surface of PP flake. The IR intensity at 1756 cm−1 increases with the decreasing Mw of PLGA, and the molecular weight of PLGA also influence the grafting of PLGA on PP. The contact angle was used to monitor the changes in hydrophilicity of PP flake surface along the treatment procedure. PLGA‐grafted PP (PP‐g‐PLGA) was eventually obtained. © 2011 Wiley Periodicals, Inc. J Appl Polym Sci, 2011
Selective recognition of chloroacetic acids by imprinted polyaniline film
Authors: Najafi Mostafa , Mollazadeh Mikael
Published: February 2011

A novel conductive imprinted polyaniline (PAN) film is prepared by adding template during the PAN film preparation. Monochloroacetic acid (MCA) and trichloroacetic acid (TCA) were used as templates. The conductivity of imprinted PAN films was measured by the four‐point probe method. The conductivity changes of imprinted PAN films were compared to reference PAN reflecting the MCA and TCA specific sites on the surface of PAN films. The conductivities were linearly dependent on the template concentrations, and linear calibration curves were obtained in the range 1–30 and 1–40 ppm of the MCA and TCA, respectively. Excellent method reproducibility (standard deviation 0.04 S/cm−1) was observed for the determination of 15 ppm MCA. The effect of various factors on preparation, properties, and recognition effects of the imprinted PAN films was investigated. The best electrical and mechanical properties were obtained with 7 × 10−4 mmol MCA as a template and doping agent. The measurements are carried out under room temperature, and the maximum conductivities are reached after about 10 and 20 min for reference and imprinted PAN film, respectively. Selectivity experiments were carried out with standard MCA, TCA, and five analogs (dichloro‐, dibromo‐, and monobromoacetic acid) in water. The results exhibited a good selectivity for the templates compared to structurally related compounds. © 2011 Wiley Periodicals, Inc. J Appl Polym Sci, 2011
Effect of chemical structure of thermoplastics on antibacterial activity and physical diffusion of triclosan doped in vinyl thermoplastics and their composites with CaCO3
Authors: Silapasorn Karn , Sombatsompop Kwannate , Kositchaiyong Apisit , Wimolmala Ekachai , Markpin Teerasak , Sombatsompop Narongrit
Published: February 2011

Triclosan was used as antibacterial agent in various vinyl thermoplastics and calcium carbonate (CaCO3)/thermoplastic composites and the antibacterial performances were studied through Halo and Plate‐Count‐Agar (PCA) test methods. The thermoplastics used were polyethylene (LDPE, MDPE, HDPE), polypropylene (PP), polystyrene (PS) and poly(vinyl chloride) (PVC). Escherichia coli (E.coli, ATCC 25922) and Stapphylococcus aureus (S.aureus, ATCC 25923) were used as the testing bacteria. The color index results suggested that introducing triclosan did not change the color of all thermoplastics used. The antibacterial results showed that the inhibition zone increased with increasing triclosan for nonpolar thermoplastics like LDPE, MDPE, HDPE, PP, and PS films whereas the opposite effect was observed for polar PVC film. The antibacterial efficacies of the triclosan decreased in the order of LDPE > MDPE > HDPE > PP > PS > PVC and this was confirmed by the triclosan releasing and FT‐IR results. The differences in the antibacterial performances of the studied thermoplastics with triclosan were associated with their rigidities, abilities to crystallize, and free volume or molecular density. The sensitivities of E.coli and S.aureus bacteria to the triclosan were found to be dependent on the testing methods used for the antibacterial performance evaluations. The addition of CaCO3 worsened the antibacterial performances in the triclosan filled HDPE and PS blends, but had a benefit for improved bacterial reduction in the triclosan‐filled PVC blend. © 2011 Wiley Periodicals, Inc. J Appl Polym Sci, 2011
Synchronization in networks of genetic oscillators with delayed coupling
Authors: Li Ping , Lam James
Published: February 2011

This paper studies the global synchronization problem for gene networks of coupled oscillators with a coupling delay. Several synchronization conditions are obtained for coupled genetic oscillators by means of Lyapunov functional theory and matrix inequality approach. More specifically, two conditions are first presented in terms of matrix inequalities, under which the synchronization can be achieved irrespective of how large the coupling delay is. Then, a sufficient condition is further proposed to ensure the synchronization of coupled genetic oscillators for a certain range of coupling delays. A numerical example of coupled Goodwin oscillators is given to illustrate the effectiveness of these conditions. Both theoretical and numerical results show that the coupling delay can affect the dynamic behaviors of coupled genetic oscillators, and the synchronized state can be significantly different from that of a single oscillator when a coupling delay is present.

Copyright © 2011 John Wiley and Sons Asia Pte Ltd and Chinese Automatic Control Society
Reconstruction of 3D contour with an active laser‐vision robotic system
Authors: Chang Wen‐Chung , Nguyen Van‐Truong , Chu Ping‐Rung
Published: February 2011

This paper presents a 3D contour reconstruction approach employing a wheeled mobile robot equipped with an active laser‐vision system. With observation from an onboard CCD camera, a laser line projector fixed‐mounted below the camera is used for detecting the bottom shape of an object while an actively‐controlled upper laser line projector is utilized for 3D contour reconstruction. The mobile robot is driven to move around the object by a visual servoing and localization technique while the 3D contour of the object is being reconstructed based on the 2D image of the projected laser line. Asymptotical convergence of the closed‐loop system has been established. The proposed algorithm also has been used experimentally with a Dr Robot X80sv mobile robot upgraded with the low‐cost active laser‐vision system, thereby demonstrating effective real‐time performance. This seemingly novel laser‐vision robotic system can be applied further in unknown environments for obstacle avoidance and guidance control tasks.

Copyright © 2011 John Wiley and Sons Asia Pte Ltd and Chinese Automatic Control Society
A best deadlock control for S3PMR to reach all states
Authors: Chao Daniel Y. , Chen Ting‐Yu , Chen Jiun‐Ting , Wu Kuo‐Chiang
Published: February 2011

This study proposes a new approach that recovers the system from deadlock states to its former live states, and reaches the same number of states as the original uncontrolled model by adding monitors (and control arcs) with no new problematic siphons. We further propose a lossless approach by coloring some arcs to avoid the material loss.

Copyright © 2011 John Wiley and Sons Asia Pte Ltd and Chinese Automatic Control Society
Confidence scores for prediction models
Authors: Gerds Thomas A. , van de Wiel Mark A.
Published: February 2011

In medical statistics, many alternative strategies are available for building a prediction model based on training data. Prediction models are routinely compared by means of their prediction performance in independent validation data. If only one data set is available for training and validation, then rival strategies can still be compared based on repeated bootstraps of the same data. Often, however, the overall performance of rival strategies is similar and it is thus difficult to decide for one model. Here, we investigate the variability of the prediction models that results when the same modelling strategy is applied to different training sets. For each modelling strategy we estimate a confidence score based on the same repeated bootstraps. A new decomposition of the expected Brier score is obtained, as well as the estimates of population average confidence scores. The latter can be used to distinguish rival prediction models with similar prediction performances. Furthermore, on the subject level a confidence score may provide useful supplementary information for new patients who want to base a medical decision on predicted risk. The ideas are illustrated and discussed using data from cancer studies, also with high‐dimensional predictor space.
Use of the environmentally sensitive fluorophore 4‐N,N‐dimethylamino‐1,8‐naphthalimide to study peptoid helix structures
Authors: Fuller Amelia A. , Seidl Frederick J. , Bruno Paul A. , Plescia Marisa A. , Palla Kanwal S.
Published: February 2011

Peptoids, oligomers of N‐substituted glycine, have been valuable targets for study and diverse application as peptidomimetics and as nanomaterials. Their conformational heterogeneity has made the study of peptoid structures using high‐resolution analyses challenging, limiting our understanding of the physiochemical features that mediate peptoid folding. Here, we introduce a new method for the study of peptoid structure that relies on the environmentally sensitive fluorescence properties of 4‐N,N‐dimethylamino‐1,8‐naphthalimide (4‐DMN). We have prepared a 4‐DMN‐functionalized primary amine that is compatible with the traditional submonomer peptoid synthesis methods and incorporated it sequence‐specifically into 11 of 13 new peptoids. When included as a peptoid side chain modification, the fluorescence emission intensity of 4‐DMN correlates with predictions of the fluorophore's local polarity within a putative structure. 4‐DMN fluorescence is maximized when the fluorophore is placed in the middle of the hydrophobic face of an amphiphilic helical peptoid. When the fluorophore is placed near the peptoid terminus or on a polar face of an amphiphilic sequence, 4‐DMN fluorescence is diminished. Disruption of the peptoid secondary structure or amphiphilicity also modulates 4‐DMN fluorescence. The peptoids' helical secondary structures are moderately disrupted by inclusion of a 4‐DMN‐modified side chain as evaluated by changes in the peptoids' CD spectral features. This new method for peptoid structure evaluation should be a valuable complement to existing peptoid structural analysis tools. © 2011 Wiley Periodicals, Inc. Biopolymers (Pept Sci) 96: 627–638, 2011.
Multi‐factorial engineering of heterologous polyketide production in Escherichia coli reveals complex pathway interactions
Authors: Boghigian Brett A. , Zhang Haoran , Pfeifer Blaine A.
Published: February 2011

Polyketides represent a significant fraction of all natural products. Many possess pharmacological activity which makes them attractive drug candidates. The production of the parent macrocyclic aglycones is catalyzed by multi‐modular polyketide synthases utilizing short‐chain acyl‐CoA monomers. When producing polyketides through heterologous hosts, one must not only functionally express the synthase itself, but activate the machinery used to generate the required substrate acyl‐CoA's. As a result, metabolic engineering of these pathways is necessary for high‐level production of heterologous polyketides. In this study, we over‐express three different pathways for provision of the two substrates (propionyl‐CoA and (2S)‐methylmalonyl‐CoA) utilized for the biosynthesis of 6‐deoxyerythronolide B (6‐dEB; the macrolactone precursor of erythromycin): (1) a propionate → propionyl‐CoA → (2S)‐methylmalonyl‐CoA pathway, (2) a methylmalonate → methylmalonyl‐CoA → propionyl‐CoA pathway, and (3) a succinate → succinyl‐CoA → (2R)‐methylmalonyl‐CoA → (2S)‐methylmalonyl‐CoA → propionyl‐CoA pathway. The current study revealed that propionate is a necessary component for greater than 5 mg L−1 titers. Deletion of the propionyl‐CoA:succinate CoA transferase (ygfH) or over‐expression of the transcriptional activator of short chain fatty acid uptake improved titer to over 100 mg L−1, while the combination of the two improved titer to over 130 mg L−1. The addition of exogenous methylmalonate could also improve titer to over 100 mg L−1. Expression of a Streptomyces coelicolor A3(2) methylmalonyl‐CoA epimerase, in conjunction with over‐expression of Escherichia coli's native methylmalonyl‐CoA mutase, allowed for the incorporation of exogenously fed succinate into the 6‐dEB core. Biotechnol. Bioeng. 2011; 108:1360–1371. © 2011 Wiley Periodicals, Inc.
Unique natural‐protein hollow‐nanofiber membranes produced by weaver ants for medical applications
Authors: Reddy Narendra , Xu Helan , Yang Yiqi
Published: February 2011

We report the properties of unique natural‐protein hollow‐nanofiber membranes produced by weaver ants (Oecophylla smaragdina) and the potential of using the nanofiber membranes for medical applications. Although natural proteins such as silk and collagen have been used to produce electrospun nanofibers for medical applications, there are no reports on producing hollow nanofibers from proteins. Hollow nanofibers are expected to have unique properties such as high drug loading. Weaver ant larvae extrude proteins in the form of nanofibers that are hollow and the adult ants build the nests using the hollow nanofibers. It was found that the nanofiber membranes are composed of fibers with average diameters of 450 nm. The membranes have tensile strength of about 4 MPa, high elongation of about 31% and modulus of 31 MPa, better than any protein nanofiber membrane reported so far. The membranes withstand rigorous boiling in weak alkali, show good attachment and proliferation of osteoblasts and can load up to 4.7 times higher drugs compared to common silk. These features make ant nanofiber membranes unique and preferable for medical and biotechnology industries. Biotechnol. Bioeng. 2011; 108:1726–1733. © 2011 Wiley Periodicals, Inc.
A novel microRNA mmu‐miR‐466h affects apoptosis regulation in mammalian cells
Authors: Druz Aliaksandr , Chu Chia , Majors Brian , Santuary Rodell , Betenbaugh Michael , Shiloach Joseph
Published: February 2011

This study determined the changes in microRNA (miRs) expression in mammalian Chinese hamster ovary (CHO) cells undergoing apoptosis induced by exposing the cells to nutrient‐depleted media. The apoptosis onset was confirmed by reduced cell viability and Caspase‐3/7 activation. Microarray comparison of known mouse and rat miRs in CHO cells exposed to fresh or depleted media revealed up‐regulation of the mouse miR‐297‐669 cluster in CHO cells subjected to depleted media. The mmu‐miR‐466h was chosen for further analysis as the member of this cluster with the highest overexpression and its up‐regulation in depleted media was confirmed with qRT‐PCR. Since miRs suppress mRNA translation, we hypothesized that up‐regulated mmu‐miR‐466h inhibits anti‐apoptotic genes and induces apoptosis. A combination of bioinformatics and experimental tools was used to predict and verify mmu‐miR‐466h anti‐apoptotic targets. 8708 predicted targets were obtained from miRecords database and narrowed to 38 anti‐apoptotic genes with DAVID NCBI annotation tool. Several genes were selected from this anti‐apoptotic subset based on nucleotide pairing complimentarity between the mmu‐miR‐466h seed region and 3′ UTR of the target mRNAs. The qRT‐PCR analysis revealed reduced mRNA levels of bcl2l2, dad1, birc6, stat5a, and smo genes in CHO cells exposed to depleted media. The inhibition of the mmu‐miR‐466h increased the expression levels of those genes and resulted in increased cell viability and decreased Caspase‐3/7 activation. The up‐regulation of mmu‐miR‐466h in response to nutrients depletion causes the inhibition of several anti‐apoptotic genes in unison. This suggests the pro‐apoptotic role of mmu‐miR‐466h and its capability to modulate the apoptotic pathway in mammalian cells. Biotechnol. Bioeng. 2011; 108:1651–1661. © 2011 Wiley Periodicals, Inc.
Glucose oxidase‐mediated polymerization as a platform for dual‐mode signal amplification and biodetection
Authors: Berron Brad J. , Johnson Leah M. , Ba Xiao , McCall Joshua D. , Alvey Nicholas J. , Anseth Kristi S. , Bowman Christopher N.
Published: February 2011

We report the first use of a polymerization‐based ELISA substrate solution employing enzymatically mediated radical polymerization as a dual‐mode amplification strategy. Enzymes are selectively coupled to surfaces to generate radicals that subsequently lead to polymerization‐based amplification (PBA) and biodetection. Sensitivity and amplification of the polymerization‐based detection system were optimized in a microwell strip format using a biotinylated microwell surface with a glucose oxidase (GOx)–avidin conjugate. The immobilized GOx is used to initiate polymerization, enabling the detection of the biorecognition event visually or through the use of a plate reader. Assay response is compared to that of an enzymatic substrate utilizing nitroblue tetrazolium in a simplified assay using biotinylated wells. The polymerization substrate exhibits equivalent sensitivity (2 µg/mL of GOx‐avidin) and over three times greater signal amplification than this traditional enzymatic substrate since each radical that is enzymatically generated leads to a large number of polymerization events. Enzyme‐mediated polymerization proceeds in an ambient atmosphere without the need for external energy sources, which is an improvement upon previous PBA platforms. Substrate formulations are highly sensitive to both glucose and iron concentrations at the lowest enzyme concentrations. Increases in amplification time correspond to higher assay sensitivities with no increase in non‐specific signal. Finally, the polymerization substrate generated a signal to noise ratio of 14 at the detection limit (156 ng/mL) in an assay of transforming growth factor‐beta. Biotechnol. Bioeng. 2011; 108:1521–1528. © 2011 Wiley Periodicals, Inc.
Sequential assembly of cell‐laden hydrogel constructs to engineer vascular‐like microchannels
Authors: Du Yanan , Ghodousi Majid , Qi Hao , Haas Nikhil , Xiao Wenqian , Khademhosseini Ali
Published: February 2011

Microscale technologies, such as microfluidic systems, provide powerful tools for building biomimetic vascular‐like structures for tissue engineering or in vitro tissue models. Recently, modular approaches have emerged as attractive approaches in tissue engineering to achieve precisely controlled architectures by using microengineered components. Here, we sequentially assembled microengineered hydrogels (microgels) into hydrogel constructs with an embedded network of microchannels. Arrays of microgels with predefined internal microchannels were fabricated by photolithography and assembled into 3D tubular construct with multi‐level interconnected lumens. In the current setting, the sequential assembly of microgels occurred in a biphasic reactor and was initiated by swiping a needle to generate physical forces and fluidic shear. We optimized the conditions for assembly and successfully perfused fluids through the interconnected constructs. The sequential assembly process does not significantly influence cell viability within the microgels indicating its promise as a biofabrication method. Finally, in an attempt to build a biomimetic 3D vasculature, we incorporated endothelial cells and smooth muscle cells into an assembled construct with a concentric microgel design. The sequential assembly is simple, rapid, cost‐effective, and could be used for fabricating tissue constructs with biomimetic vasculature and other complex architectures. Biotechnol. Bioeng. 2011; 108:1693–1703. © 2011 Wiley Periodicals, Inc.
Design and construction of improved new vectors for Zymomonas mobilis recombinants
Authors: Dong Hong‐Wei , Bao Jie , Ryu Dewey D.Y. , Zhong Jian‐Jiang
Published: February 2011

Zymomonas mobilis is a very important gram‐negative bacterium having a potential application to simultaneous co‐production of biofuel and other high value‐added products through biorefinery process technology development. Up to now, pLOI193 has been used as the plasmid of choice for Z. mobilis strains. However, its application has been limited due to its relatively low transformation efficiency, a large plasmid size (13.4 kb), and limited choice of cloning sites for gene manipulations. Some of these limitations can be overcome by the newly designed and constructed plasmid pHW20a, which provides significantly higher transformation efficiency (about two orders of magnitude greater), better stability (for at least 120 generation times), and an ease of gene manipulations. The pHW20a contains three complete cis‐acting genes (repA, repB, and repC) encoding the Rep proteins for primosome formation. It has the origin of replication (oriV) to ensure replication in gram‐negative bacteria, two mob genes that enhances transformation efficiency, a screening marker (lacZα), expanded multiple cloning sites (MCS) that enables easy gene manipulation, and the tetracycline resistance gene (tcr). The utility of screening marker, lacZα with MCS, was confirmed by the blue‐white screening test. Several examples of applications of gene expression in Z. mobilis ZM4 have been demonstrated in this article by using several new pHW20a‐derived plasmids and expressing the homologous genes (gfo and ppc) and the heterologous genes (bglA, mdh, and fdh1). The results show that pHW20a is a very useful new vector for construction of new Z. mobilis recombinant strains that will enable simultaneous co‐production of biofuel and high value added products. Biotechnol. Bioeng. 2011; 108:1616–1627. © 2011 Wiley Periodicals, Inc.
Room temperature ionic liquids as emerging solvents for the pretreatment of lignocellulosic biomass
Authors: Mora‐Pale Mauricio , Meli Luciana , Doherty Thomas V. , Linhardt Robert J. , Dordick Jonathan S.
Published: February 2011

Room temperature ionic liquids (RTILs) are emerging as attractive and green solvents for lignocellulosic biomass pretreatment. The unique solvating properties of RTILs foster the disruption of the 3D network structure of lignin, cellulose, and hemicellulose, which allows high yields of fermentable sugars to be produced in subsequent enzymatic hydrolysis. In the current review, we summarize the physicochemical properties of RTILs that make them effective solvents for lignocellulose pretreatment including mechanisms of interaction between lignocellulosic biomass subcomponents and RTILs. We also highlight several recent strategies that exploit RTILs and generate high yields of fermentable sugars suitable for downstream biofuel production, and address new opportunities for use of lignocellulosic components, including lignin. Finally, we address some of the challenges that remain before large‐scale use of RTILs may be achieved. Biotechnol. Bioeng. 2011;108:1229–1245. © 2011 Wiley Periodicals, Inc.
FPGA‐Matlab‐based open core for three‐time controllers in automatic control applications
Authors: de Jesus Rangel‐Magdaleno Jose , Rivera‐Guillen Jesus Rooney , de Jesus Romero‐Troncoso Rene , Osornio‐Rios Roque Alfredo
Published: February 2011

Automatic control is present in most industrial applications and engineering. The automatic control practice with the physical implementation of the controller is a major issue to be covered in undergraduate/graduate engineering course, and those issues dealing with subjects such as automation, control, electromechanics, mechatronics, manufacturing, and robotics which should be included in their curricula. The contribution of this work is the development of an open core of a three‐time controller under FPGA technology applied in a standard control course, allowing students to have a real‐time control implementation with technological independence and high level of integration. The combination of both, theory and practice is important. Thus, this course's proposal develops the theoretical bases in practical form. The opportunity to control a servomotor demands students with area proficiency, which is reflected in a project development. © 2011 Wiley Periodicals, Inc. Comput Appl Eng Educ 21:E132–E140, 2013
A quantum chemical and chemometric study of sesquiterpene lactones with cytotoxicity against tumor cells
Authors: Arantes Francisco F. P. , Barbosa Luiz C. A. , Maltha Célia R. A. , Demuner Antônio J. , Fidêncio Paulo H. , Carneiro José Walkimar M.
Published: February 2011

The semi‐empirical molecular orbital method PM6 was employed to calculate a set of molecular descriptors of 20 sesquiterpene lactones (SQLs) with cytotoxicity against HL‐60 (leukemia) tumor cells. The principal component analysis (PCA) and hierarchical cluster analysis (HCA) methods were used to obtain possible relationships between the calculated descriptors and the biological activity of the lactones. Four descriptors were identified as responsible for the separation between the active and inactive compounds: EHOMO (highest occupied molecular orbital energy); Q11 (net atomic charge on C11); Q12 (net atomic charge on C12) and Q13 (net atomic charge on C13). These results indicated that the presence of the α‐methylene‐γ‐lactone group has a significant role in the mechanism by which SQLs exert their biological activities.In order to deepen our knowledge about the structure–activity relationship of sesquiterpene lactones (SQLs), a quantum chemical and chemometric study of sesquiterpene lactones with cytotoxicity was performed against HL‐60 (leukemia) tumor cells. The analysis of the molecular descriptors identified as responsible for the separation between the active and inactive compounds indicated that the presence of the α‐methylene‐γ‐lactone functionality has a significant role in the mechanism by which SQLs exert their biological activities. Copyright © 2011 John Wiley & Sons, Ltd.
ChemInform Abstract: Synthesis of New LnxBi2‐xSe3 (Ln: Sm3+, Eu3+, Gd3+, Tb3+) Nanomaterials and Investigation of Their Optical Properties.
Authors: Alemi Abdolali , Klein Axel , Meyer Gerd , Dolatyari Mahboubeh , Babalou Aliakbar
Published: February 2011

The new luminescent title materials (0 ≤ x ≤ 0.6) are synthesized by hydrothermal reaction of Bi(NO3)3, Sm2O3, Eu2O3, Gd2O3, Tb4O7, grey selenium, EDTA, NaOH, N2H4·H2O, and H2O (autoclave, 180 °C, 48 h, 90—95% yield).
ChemInform Abstract: Structural and Magnetic Properties of C15 HoMn2 Hydrides.
Authors: Budziak A. , Zachariasz P. , Kolwicz‐Chodak L. , Figiel H. , Pacyna A. , Zukrowski J.
Published: February 2011

Powder samples of cubic HoMn2Hx (0 ≤ x ≤ 4.3) are characterized by powder XRD and AC/DC magnetometry as a function of temperature and external magnetic field.
ChemInform Abstract: Synthesis, Crystal Structure and Nonlinear Optical Property of Rb3V5O14.
Authors: Pan Jianguo , Li Yuebao , Cui Yuejie , Zhao Lingyan , Li Xing , Han Lei
Published: February 2011

The title compound is synthesized by solid state reaction of Rb2CO3 with 3% excess V2O5 (500 °C, Pt crucible, 24 h).
ChemInform Abstract: Crystal Structure, Thermal and Magnetic Properties of Cr2V4O13.
Authors: Patwe S. J. , Achary S. N. , Manjanna J. , Kadam R. M. , Salunke H. G. , Tyagi A. K.
Published: February 2011

The title compound is synthesized by solid state reaction of stoichiometric amounts of V2O5 and Cr2O3 at 630 °C and its crystal structure is determined by powder XRD.
ChemInform Abstract: Chiral Primary Amine Thiourea Promoted Highly Enantioselective Michael Reactions of Isobutyraldehyde with Maleimides.
Authors: Bai Jian‐Fei , Peng Lin , Wang Liang‐liang , Wang Li‐Xin , Xu Xiao‐Ying
Published: February 2011

A variety of N‐aryl and N‐alkyl maleimides react smoothly with isobutylaldehyde in the presence of a chiral diamine‐derived thiourea catalyst to give the Michael adducts in excellent yields and enantioselectivities (up to 99% e.e.).
ChemInform Abstract: Aqueous Aza‐Michael Reaction of Conjugated Alkenes: Toward Spermine.
Authors: Joshi Jigar H. , Saiyed Akeel S. , Bedekar Ashutosh V.
Published: February 2011

Aza‐Michael reaction of amines with conjugated alkenes in water is efficiently achieved without the addition of any additives.
ChemInform Abstract: Highly Chemoselective Palladium‐Catalyzed Cross‐Trimerization Between Alkyne and Alkenes Leading to 1,3,5‐Trienes or 1,2,4,5‐Tetrasubstituted Benzenes with Dioxygen.
Authors: Zhou Peng , Huang Liangbin , Jiang Huanfeng , Wang Azhong , Li Xianwei
Published: February 2011

The O2/LiCl/K2CO3‐mediated reaction of alkynes with an excess of alkenes allows new and environmentally friendly access to 1,3,5‐trienes.
ChemInform Abstract: InCl3/CyNH2 Cocatalyzed Carbocyclization Reaction: An Entry to α‐Disubstituted exo‐Methylene Cyclopentanes
Authors: Montaignac Benjamin , Vitale Maxime R. , Ratovelomanana‐Vidal Virginie , Michelet Veronique
Published: February 2011

via an efficient and cheap access
ChemInform Abstract: Cinchona Alkaloid‐Catalyzed Asymmetric Trifluoromethylation of Alkynyl Ketones with Trimethylsilyl Trifluoromethane.
Authors: Kawai Hiroyuki , Tachi Kentaro , Tokunaga Etsuko , Shiro Motoo , Shibata Norio
Published: February 2011

Product (Va) is a suitable substrate for the synthesis of biologically attractive aryl and heteroaryl trifluoromethyl carbinols.
ChemInform Abstract: Reusable Polystyrene‐Supported Pd Catalyst for Mizoroki—Heck Reactions with Extremely Low Amounts of Supported Pd.
Authors: Diebold Carine , Schweizer Stephane , Becht Jean‐Michel , Le Drian Claude
Published: February 2011

The catalyst can be reused three times with significant yield drop afterwards.
ChemInform Abstract: 1,3,2,4‐Diazadiphosphetidines as Ligand and Base for Palladium‐Catalyzed Suzuki‐Miyaura, Sonogashira—Hagihara, and Homocoupling Reactions of Aryl Halides under Heterogeneous Conditions in Water.
Authors: Iranpoor Nasser , Firouzabadi Habib , Tarassoli Abbas , Fereidoonnezhad Masood
Published: February 2011

A novel diazadiphosphetidine is prepared and successfully applied as a ligand in a variety of palladium‐catalyzed coupling reactions of halides (I) in water.
ChemInform Abstract: Polyethylene Glycol (PEG 300) and Water—Ethanol as Benign Solvent Systems for the Synthesis of a Novel Series of 2‐Hydroxynaphthalen‐1(4H)‐ones.
Authors: Villemin D. , Benabdallah M. , Choukchou‐Braham N. , Mostefa‐Kara B.
Published: February 2011

In water‐ethanol at 40 °C the yields are lower than using the presented grinding method.
ChemInform Abstract: Synthesis of Substituted (S)‐2‐Aminotetralins via Ring‐Opening of Aziridines Prepared from L‐Aspartic Acid β‐tert‐Butyl Ester.
Authors: Aaseng Jon Erik , Gautun Odd R.
Published: February 2011

Key steps of the synthesis of optically active aminotetralins (VI) are the regioselective ring opening of aziridine (II) (or its Cbz analogue) with in situ generated arylcuprate reagents as well as Friedel—Crafts cyclization of the free acids (IV) (not optimized).
ChemInform Abstract: Synthesis of β‐Trifluoromethylated Δ1‐Pyrrolines.
Authors: Marrec Olivier , Christophe Carole , Billard Thierry , Langlois Bernard , Vors Jean‐Pierre , Pazenok Sergii
Published: February 2011

Trifluoromethylated title compounds (III) are easily synthesized in a one‐pot procedure from β‐(trifluoromethyl)enones and isolated predominantly as the trans‐isomer.
ChemInform Abstract: Facile Synthesis of 2‐Bromoindoles by Ligand‐Free CuI‐Catalyzed Intramolecular Cross‐Coupling of gem‐Dibromoolefins.
Authors: Jiang Baishan , Tao Kemei , Shen Wang , Zhang Jiancun
Published: February 2011

Optimal results are obtained if mesyl‐substituted aniline substrates are used.
ChemInform Abstract: Synthesis of Fluorine‐Containing Benzimidazole Derivatives.
Authors: Vasilyeva T. P. , Karimova N. M. , Slavich Yu. V.
Published: February 2011

Convenient methods for the synthesis of benzimidazoles containing fluoroalkyl substituents in position 2 starting from phenylenediamines (I) are developed.
ChemInform Abstract: C—H Bond Functionalization in the Synthesis of Fused 1,2,3‐Triazoles.
Authors: Panteleev Jane , Geyer Karolin , Aguilar‐Aguilar Angelica , Wang Letian , Lautens Mark
Published: February 2011

A synthesis of polycyclic frameworks including a 1,2,3‐triazole unit is developed.
ChemInform Abstract: An Easy Synthetic Approach to 1,2,3‐Triazole‐Fused Heterocycles.
Authors: Fiandanese Vito , Marchese Giuseppe , Punzi Angela , Iannone Francesco , Rafaschieri Giacomo G.
Published: February 2011

An efficient synthesis of triazole‐fused isoindoles and isoquinolines is presented.
ChemInform Abstract: Reaction of Heterocyclic Enamines with Nitrile Oxide and Nitrilimine Precursors.
Authors: Altug Cevher , Dueruest Yasar , Elliot Mark C. , Kariuki Benson M. , Rorstad Tillique , Zaal Mark
Published: February 2011

A range of novel heterocyclic compounds is prepared from alkylidenepyrrolidines and 1,3‐dipoles such as nitrile oxides, nitrilimines or their precursors.