bluuebunny/crossref_metadata_2025 huggingface dataset:
Broad band microstrip antenna with 100 μM slits on elevated edges for C‐ and X‐band communication
Authors: Bordoloi Anup Kr. , Borah Pranjal , Bhattacharyya Satyajib , Bhattacharyya Nidhi S.
Published: March 2013

In the present work, a rectangular microstrip patch antenna having 100 μm slits on the conductor parellel to and 2.5 mm from the radiating edges on both sides is designed.The conductor sections from the slits to the outer edges are elevated at an angle from the conductorplane. Prominent return loss peaks are obtained at 4.23 GHz and 10.26 GHz with return losses of −36 dB and −32 dB, respectively. A large frequency envelope with at least −10 dB return loss in the range 6.84 GHz to 9.24 GHz for elevation angle 65° and 8.45 GHz to 10.54 GHz for elevation angle 85° are obtained. The frequencies can be varied by changing the elevation angles. © 2013 Wiley Periodicals, Inc. Microwave Opt Technol Lett 55:1285–1287, 2013; View this article online at wileyonlinelibrary.com. DOI 10.1002/mop.27560
Miniaturized quasi‐lumped coupled‐line single‐section directional coupler designed in multilayer LTCC technology
Authors: Piekarz Ilona , Sorocki Jakub , Wincza Krzysztof , Gruszczynski Slawomir , Muller Jens , Welker Tilo
Published: March 2013

The design of a miniaturized broadband directional coupler realized with the use of a quasi‐lumped element approach has been presented.The designed coupler takes advantage of Low Temperature Co‐fired Ceramics (LTCC) technology, in which miniaturized coupled inductors are realized with the use of a multilayer stacked structure being vital in terms of possible miniaturization of the circuit. It has been shown that the mutual coupling between consecutive turns of the spiral coupled inductors deteriorate the coupler's performance which can be improved when appropriate mutual and shunt capacitances are added. The theoretical analysis as well as measurements of a 3‐dB directional coupler operating at f0 = 1.5 GHz have been presented. © 2013 Wiley Periodicals, Inc. Microwave Opt Technol Lett 55:1401–1405, 2013; View this article online at wileyonlinelibrary.com. DOI 10.1002/mop.27582
A low‐profile dual‐layer ultra‐wideband frequency selective surface reflector
Authors: Ranga Yogesh , Matekovits Ladislau , Weily Andrew R. , Esselle Karu P.
Published: March 2013

An ultra‐wideband (UWB), dual‐layer frequency selective surface (FSS) is presented.This compact low‐profile FSS has been designed as a reflector for UWB antennas. It can be inserted between a planar UWB antenna and a nearby parallel conducting surface such as a circuit board, screen, or a metal case, to isolate them and to prevent antenna impedance mismatch otherwise caused by the conductor. The measured transmission coefficient magnitude of the FSS is less than −10 dB over a 133% bandwidth and its reflection phase is appropriate for this and other similar reflector applications, over an UWB. © 2013 Wiley Periodicals, Inc. Microwave Opt Technol Lett 55:1223–1227, 2013; View this article online at wileyonlinelibrary.com. DOI 10.1002/mop.27583
An efficient, broad bandwidth, high directivity, electrically small antenna
Authors: Ziolkowski Richard W. , Tang Ming‐Chun , Zhu Ning
Published: March 2013

Fundamental physics limits the performance characteristics of passive electrically small antennas. A 300 MHz design, which includes non‐Foster elements and exceeds those limits, is reported. It simultaneously achieves high radiation efficiencies (>81.63%), high directivities (>6.25 dB), and large front‐to‐back‐ratios (>26.71 dB) over a 10.0% fractional bandwidth. © 2013 Wiley Periodicals, Inc. Microwave Opt Technol Lett 55:1430–1434, 2013; View this article online at wileyonlinelibrary.com. DOI 10.1002/mop.27587
Low power, high gain, low noise amplifier (LNA) for ultra wide‐band applications
Authors: Iji Ayobami , Zhu Xie , Heimlich Michael
Published: March 2013

One of the important components of a receiver is the low noise amplifier (LNA). The challenges of LNA design include ability to achieve high gain, low noise figure, and better linearity at low power consumption within the required frequency. In this article, our design is based on Impulse Response (IR) Ultra Wide‐Band (UWB) transceiver operating at 3.1–4.6 GHz. Hence, the LNA designed has been optimized for low noise figure, considerably high gain and better linearity at low power consumption, which make it suitable for implantable radio application. The process technology used here is 0.25 μm CMOS Silanna process. © 2013 Wiley Periodicals, Inc. Microwave Opt Technol Lett 55:1399–1401, 2013; View this article online at wileyonlinelibrary.com. DOI 10.1002/mop.27588
High isolation tri‐band BPF using tri‐mode resonator
Authors: Chen Hui
Published: March 2013

A compact tri‐band bandpass filter (BPF) with high isolation and selectivity is proposed in this article, which is based on a tri‐mode rectangular open‐loop resonator (ROLR) loaded by an open‐circuited stub. Characterized by both theoretical analysis and full‐wave EM simulation, the proposed resonator is found to have the advantage that the first‐ and third‐mode resonant frequencies can be flexibly controlled by the length of the open‐circuited stub, whereas the second‐mode resonant frequency is mainly determined by the length of the ROLR. With the multipath propagation mode configuration of the two resonators, the transmission zeros among each passband are generated to improve passband selectivity and achieve high isolation. Theoretical prediction is verified by the experimental result of the proposed tri‐band BPF. © 2013 Wiley Periodicals, Inc. Microwave Opt Technol Lett 55:1367–1370, 2013; View this article online at wileyonlinelibrary.com. DOI 10.1002/mop.27596
Natural course of muscular involvement assessed by a new computed tomography method in Duchenne muscular dystrophy
Authors: Kuru Satoshi , Sakai Motoko , Tanaka Nobuhiko , Konagaya Masaaki , Nakayam Takahiro , Kawai Mitsuru
Published: March 2013

Aim

Establishing the natural course of muscular impairment in Duchenne muscular dystrophy (DMD) is essential for defining the effect of treatments in clinical trials. We retrospectively investigated the change of thigh muscle volume in DMD using new indices, muscle volume index (MVI) and %MVI.

Methods

MVI is the estimated muscle volume contained within a given computed tomography (CT) slice and calculated using the CT histogram‐based procedure after correcting for a partial volume effect. %MVI is calculated by dividing the MVI by the entire volume of the region of interest. We applied this method to 49 retrospectively selected CT images from 21 patients with DMD, aged 6–13 years, at a relatively early stage.

Results

Both MVI and %MVI were found to have a significant inverse correlation with the clinical disability stage. In most patients, the changes over time in MVI and %MVI could be regressed to the exponential function Y = Ae−rX. The rate constant of the approximation curve was 0.299 ± 0.072 for MVI, and 0.351 ± 0.088 for %MVI, respectively.

Conclusion

MVI and %MVI have proven useful for follow‐up assessments of skeletal muscle volume in patients with DMD. Our retrospective longitudinal study should provide a basis for evaluating therapeutic interventions in future clinical trials.
Serum adiponectin levels are associated with hepatitis B viral load in overweight to obese hepatitis B virus carriers
Authors: Chiang Chien‐Hsieh , Lai Jin‐Shin , Hung Shou‐Hung , Lee Long‐Teng , Sheu Jin‐Chuan , Huang Kuo‐Chin
Published: March 2013

Objective:

This study aimed to investigate the association between serum adiponectin and chronic hepatitis B virus (HBV) infection.

Design and Methods:

We conducted a campus‐based cross‐sectional study in Northern Taiwan, an HBV‐endemic country. A total of 506 participants, including 147 chronic HBV‐infected individuals and 359 healthy controls, were assessed for anthropometric indices, serum adiponectin levels, serum HBV viral load and markers, serum alanine aminotransferase levels and metabolic factors.

Results:

Older age, male gender, higher alanine aminotransferase, higher body mass index, greater waist circumference, lower fasting glucose, higher triglycerides, and higher adiponectin were associated with chronic HBV infection in univariate analyses. In multivariate analysis, the presence of chronic HBV infection was positively associated with serum adiponectin levels (P < 0.0001) and high adiponectin levels over the 75th percentile (odds ratio, 4.25; 95% confidence interval, 2.36‐7.66; P < 0.0001) after adjusting for age, gender, body mass index, and insulin resistance index. Furthermore, serum adiponectin levels were positively associated with HBV viral load in overweight to obese HBV‐infected subjects (P = 0.018).

Conclusion:

Although chronic HBV‐infected individuals were heavier than healthy controls, they had significantly higher serum adiponectin levels than healthy counterparts. Additionally, adiponectin levels were positively associated with HBV viral load in overweight to obese HBV‐infected subjects. Future research should focus on elucidating adiponectin pathways, which may contribute to the development of adjuvant treatments for chronic HBV infection.
Gastric emptying and Ca2+ and K+ channels of circular smooth muscle cells in diet‐induced obese prone and resistant rats
Authors: Li Shiying , Maude‐Griffin Roland , Pullan Andrew J. , Chen Jiande D Z
Published: March 2013

Objective:

Accelerated gastric emptying that precipitates hunger and frequent eating could be a potential factor in the development of obesity. The aim of this study was to study gastric emptying in diet‐induced obese‐prone (DIO‐P) and DIO‐resistant (DIO‐R) rats and explore possible differences in electrical properties of calcium (Ca2+) and potassium (K+) channels of antral circular smooth muscle cells (SMCs).

Design and Methods:

Whole‐cell patch‐clamp technique was used to measure Ca2+ and K+ currents in single SMCs. Gastric emptying was evaluated 90 min after the ingestion of a solid meal.

Results:

Solid gastric emptying in the DIO‐P rats was significantly faster compared with that in the DIO‐R rats. The peak amplitude of L‐type Ca2+ current (IBa,L) at 10 mV in DIO‐P rats was greater than that in DIO‐R rats without alternation of the current–voltage curve and voltage‐dependent activation and inactivation. The half‐maximal inactivation voltage of transient outward K+ current (IKto) was more depolarized (∼4 mV) in DIO‐P rats compared with that in DIO‐R rats. No difference was found in the current density or recovery kinetics of IKto between two groups. The current density of delayed rectifier K+ current (IKdr), which was sensitive to tetraethylammonium chloride but not 4‐aminopyridine, was lower in DIO‐P rats than that in DIO‐R rats.

Conclusion:

The accelerated gastric emptying in DIO‐P rats might be attributed to a higher density of IBa,L, depolarizing shift of inactivation curve of IKto and lower density of IKdr observed in the antral SMCs of DIO‐P rats.
Obesity and early mortality in the United States
Authors: Greenberg James A.
Published: March 2013

Objective:

Although obesity is a serious public health problem, there are few reliable measures of its health hazards in the United States. The objective of this study was to estimate how much earlier mortality is likely to occur for Americans who are obese (body mass index [BMI], ≥ 30).

Design and Methods:

Data from the National Health and Nutrition Examination Survey (NHANES) I (1971–1975), NHANES II (1976–1980), and NHANES III (1988–1994) for 37,632 participants who experienced 8,791 deaths during 15 years of follow‐up were prospectively analyzed. The relative risk of death from all causes and its advancement period, adjusted for covariates, were calculated. Stratification was used to investigate the effects of pre‐existing illness, smoking, and older age on the advancement period.

Results:

Compared to the participants of reference weight (BMI, 23 to <25 kg/m2), mortality was likely to occur 9.44 years (95% confidence interval [CI]: 0.72, 18.16) earlier for those who were obese (BMI, ≥ 30). For overweight (25 to <30 kg/m2), grade 1 obesity (BMI, 30 to <35) and grades 2–3 obesity (BMI, ≥ 35.0), the mortality was likely to occur earlier by 4.40 (−3.90, 12.70), 6.69 (−2.06, 15.43), and 14.16 (3.35, 24.97) years, respectively. These estimates apply to healthy nonsmoker young‐ and middle‐aged (21–55 years) adults, who constituted an estimated 32.8% of Americans with age of >21 years between 1988 and 1994. Without stratifying simultaneously for preexisting illness, smoking, and age, values of the advancement period for obesity were markedly smaller than those observed for healthy nonsmoker young and middle‐aged adults.

Conclusions:

For healthy nonsmokers young‐ and middle‐aged adults who constitute about one‐third of American adults, being obese is likely to hasten mortality by 9.44 years.
Adaptive thermogenesis with weight loss in humans
Authors: Müller M.J. , Bosy‐Westphal A.
Published: March 2013

Adaptive thermogenesis (AT) with weight loss refers to underfeeding‐associated fall in resting and non‐resting energy expenditure (REE, non‐REE); this is independent of body weight and body composition. In humans, the existence of AT was inconsistently shown and its clinical significance has been questioned.

Objectives:

Discrepant findings are mainly due to different definitions of AT, the use of various and nonstandardized study protocols, and the limits of accuracy of methods to assess energy expenditure. With controlled underfeeding, AT takes more than 2 wk to develop. AT accounts to an average of 0.5 MJ (or 120 kcal) with a considerable between subject variance.

Design and Methods:

Low‐sympathetic nervous system activity, 3,5,3′‐tri‐iodothyronine (T3) and leptin are likely to add to AT; however, the kinetic changes of their plasma levels with underfeeding differ from the time course of AT and controlled intervention studies substituting and titrating these hormones are rare in humans. AT in response to underfeeding is independent of thermogenesis in response to either diet or cold. Although fat‐free mass (FFM) and, thus, liver, and skeletal muscle are considered as major sites of AT, cold‐induced nonshivering thermogenesis relates to the metabolism of brown adipose tissue (BAT). In humans, diet‐induced thermogenesis is related to postprandial substrate metabolism of FFM with a questionable role of BAT. Obviously, the REE component of AT differs from and its non‐REE component with respect to organ contribution as well as mechanisms. Thus, AT cannot be considered as unique.

Conclusions:

AT should be characterized based on individual components of daily energy expenditure, detailed body composition analyses, and mathematical modeling. The biological basis of AT as well as the influences of age, sex, obesity, stress, and inflammation remain to be established in humans.
Effects of increased meal frequency on fat oxidation and perceived hunger
Authors: Ohkawara Kazunori , Cornier Marc‐Andre , Kohrt Wendy M. , Melanson Edward L
Published: March 2013

Objective:

Consuming smaller, more frequent meals is often advocated as a means of controlling body weight, but studies demonstrating a mechanistic effect of this practice on factors associated with body weight regulation are lacking. The purpose of this study was to compare the effect of consuming three (3M) vs. six meals (6M) per day on 24‐h fat oxidation and subjective ratings of hunger.

Design and Methods:

Lean (body mass index <25 kg/m2) subjects (7M, 8F) were studied in a whole‐room calorimeter on two occasions in a randomized cross‐over design. Subjects were provided isoenergetic, energy balanced diets with a 1‐ to 2‐week washout between conditions. Hunger, fullness, and “desire to eat” ratings were assessed throughout the day using visual analog scales and quantified as area under the curve (AUC).

Results:

There were no differences (P < 0.05) in 24‐h energy expenditure (8.7 ± 0.3 vs. 8.6 ± 0.3 mj d−1), 24‐h respiratory quotient (0.85 ± 0.01 vs. 0.85 ± 0.01), or 24‐h fat oxidation (82 ± 6 vs. 80 ± 7 g day‐1) between 3M and 6M, respectively. There was no difference in fullness 24‐h AUC, but hunger AUC (41850 ± 2255 vs. 36612 ± 2556 mm.24 h, P = 0.03) and “desire to eat” AUC (47061 ± 1791 vs. 41170 ± 2574 mm.24 h, P = 0.03) were greater during 6M than 3M.

Conclusion:

We conclude that increasing meal frequency from three to six per day has no significant effect on 24‐h fat oxidation, but may increase hunger and the desire to eat.
High and low activity rats: Elevated intrinsic physical activity drives resistance to diet‐induced obesity in non‐bred rats
Authors: Perez‐Leighton Claudio E. , Boland Kelsey , Billington Charles J. , Kotz Catherine M.
Published: March 2013

Objective:Humans and rodents show large variability in their individual sensitivity to diet‐induced obesity (DIO), which has been associated with differences in intrinsic spontaneous physical activity (SPA). Evidence from genetic and out‐bred rat obesity models shows that higher activity of the orexin peptides results in higher intrinsic SPA and protection against DIO. Based on this, we hypothesized that naturally occurring variation in SPA and orexin signaling is sufficient to drive differences in sensitivity to DIO.

Design and Methods:Orexin expression, behavioral responses to orexin‐A, basal energy expenditure and sensitivity to DIO were measured in in non‐manipulated male Sprague‐Dawley rats selected for high and low intrinsic SPA.

Results:Male Sprague‐Dawley rats were classified as high‐activity or low‐activity based on differences in intrinsic SPA. High‐activity rats showed higher expression of prepro‐orexin mRNA, higher sensitivity to behavioral effects of orexin injection, higher basal energy expenditure and were more resistant to obesity caused by high‐fat diet consumption than low‐activity rats.

Conclusion:Our results define a new model of differential DIO sensitivity, the high‐activity and low‐activity rats, and suggest that naturally occurring variations in intrinsic SPA cause differences in energy expenditure that are mediated by orexin signaling and alter DIO sensitivity.
Divergent neural substrates of inhibitory control in binge eating disorder relative to other manifestations of obesity
Authors: Balodis Iris M. , Molina Nathan D. , Kober Hedy , Worhunsky Patrick D. , White Marney A. , Rajita Sinha  , Grilo Carlos M. , Potenza Marc N.
Published: March 2013

Objective:

An important endeavor involves increasing our understanding of biobehavioral processes underlying different types of obesity. The current study investigated the neural correlates of cognitive control (involving conflict monitoring and response inhibition) in obese individuals with binge eating disorder (BED) as compared to BMI‐matched non‐BED obese (OB) individuals and lean comparison (LC) participants. Alterations in cognitive control may contribute to differences in behavioral control over eating behaviors in BED and obesity.

Design and Methods:

Participants underwent functional magnetic resonance imaging while completing the Stroop color‐word interference task.

Results and Conclusions:

Relative to the OB and LC groups, activity in the BED group was differentiated by relative hypoactivity in brain areas involved in self‐regulation and impulse control. Specifically, the BED group showed diminished activity in the ventromedial prefrontal cortex (vmPFC), inferior frontal gyrus (IFG), and insula during Stroop performance. In addition, dietary restraint scores were negatively correlated with right IFG and vmPFC activation in the BED group, but not in the OB or HC groups. Thus, BED individuals' diminished ability to recruit impulse‐control‐related brain regions appears associated with impaired dietary restraint. The observed differences in neural correlates of inhibitory processing in BED relative to OB and LC groups suggest distinct eurobiological contributions to binge eating as a subgroup of obese individuals.
Serum hemorphin‐7 levels are decreased in obesity
Authors: Maraninchi Marie , Feron Delphine , Fruitier‐Arnaudin Ingrid , Bégu‐Le Corroller Audrey , Nogueira Juan P. , Mancini Julien , Valéro René , Piot Jean M. , Vialettes Bernard
Published: March 2013

Objective:

Hemorphin peptides exhibit biological activities that interfere with the endorphin system, the inflammatory response, and blood‐pressure control. VV‐hemorphin‐7 and LVV‐hemorphin‐7 peptides exert a hypotensive effect, in particular, by inhibiting the renin–angiotensin system. Furthermore, levels of circulating hemorphin‐7 peptides have been found to be decreased in diseases such as type 1 and type 2 diabetes.

Design and Methods:

Because type 2 diabetes and obesity share common features, such as insulin resistance, microinflammation, high glomerular‐filtration rate (GFR), and cardiovascular risk, we evaluated serum VV‐hemorphin‐7 like immunoreactivity (VVH7‐i.r.) levels, using an enzyme‐linked immunosorbent assay method, on a group of 54 obese subjects without diabetes or hypertension, compared with a group of 33 healthy normal‐weight subjects.

Results:

Circulating VVH7‐i.r. levels were significantly decreased in the obese group compared with the control group (1.98 ± 0.19 vs. 4.86 ± 0.54 µmol/l, respectively, P < 0.01), and a significant negative correlation between VVH7‐i.r. and diastolic blood pressure (DBP) was found in obese patients (r = −0.35, P = 0.011). There was no significant correlation between VVH7‐i.r. level and insulin resistance, metabolic syndrome, or GFR.

Conclusions:

The decreased serum hemorphin‐7 found in obese subjects, as in diabetes, may contribute to the development of hypertension and to the cardiovascular risk associated with these metabolic diseases.
Adherence to behavioral targets and treatment attendance during a pediatric weight control trial
Authors: Theim Kelly R. , Sinton Meghan M. , Goldschmidt Andrea B. , Van Buren Dorothy J. , Doyle Angela C. , Saelens Brian E. , Stein Richard I. , Epstein Leonard H. , Wilfley Denise E.
Published: March 2013

Objective:

Better weight loss outcomes are achieved in adults and youth who adhere to obesity treatment regimens (i.e., session attendance and prescribed changes in weight control behaviors). However, more research is needed regarding children's adherence to a range of behaviors relevant for weight maintenance over long‐term follow‐up.

Design and Methods:

Overweight children (N = 101, aged 7‐12 years), along with an overweight parent, participated in a 20‐week family‐based behavioral weight loss treatment (FBT) and were then assigned to either a behaviorally focused or socially focused 16‐week weight maintenance treatment (MT). Treatment attendance and child and parent adherence (i.e., reported use of skills targeted within treatment) were examined in relation to child percent overweight change from baseline to post‐FBT, post‐MT, and 2‐year follow‐up.

Results:

Higher attendance predicted better child weight outcomes at post‐MT, but not at 2‐year follow‐up. Adherence to self‐regulatory skills/goal‐setting skills predicted child weight outcomes at 2‐year follow‐up among the behaviorally focused MT group.

Conclusions:

Future research is needed to examine mediators of change within family‐based weight control interventions, including behavioral and socially based targets. Incorporating self‐regulatory weight maintenance skills into a comprehensive MT may maximize children's sustained weight control.
Synthesis and characterization of PMMA/SiO2 organic–inorganic hybrid materials via RAFT‐mediated miniemulsion polymerization
Authors: Ma Jianying , Lu Mangeng , Cao Chunlei , Zhang Huixuan
Published: March 2013

In this article, we first carried out the surface modification of SiO2 using silane coupling agent KH570, and then prepared PMMA/SiO2 organic–inorganic hybrid materials by conventional free radical polymerization and RAFT polymerization in miniemulsion, respectively. The kinetics comparisons of these two polymerizations were studied. PMMA/SiO2 hybrid materials were characterized by gel permeation chromatography, differential scanning calorimetry and thermogravimetric analysis. Experimental results indicated that the polymerization behavior of MMA in miniemulsion showed controlled/living radical polymerization characteristics under the control of RAFT agent. Incorporation of RAFT agent and SiO2 nanoparticles improved the thermal properties of polymers, the thermal stability of polymers increased with increasing content of SiO2 nanoparticles. The structures and morphologies of SiO2, modified SiO2, and PMMA/SiO2 hybrid materials were characterized by FT‐IR and TEM. TEM results showed that the addition of modified SiO2 nanoparticles to miniemulsion polymerization system obtained different morphology latex particles. Most of modified SiO2 nanoparticles were wrapped by polymer matrix after polymerization. POLYM. COMPOS., 2013. © 2013 Society of Plastics Engineers
Preparation of thermosensitive and visible‐light responsible composites based on hydrogels of N‐isopropylacrylamide/maleic anhydride‐modified β‐cyclodextrin copolymer and TiO2/multiwalled carbon nanotubes particles for degradation of methyl orange
Authors: Wang Hui‐Long , Liu Ling‐Yun , Kou Wei‐Qun , Jiang Wen‐Feng
Published: March 2013

The novel thermosensitive and visible‐light responsible composites composed of poly(N‐isopropylacrylamide‐co‐maleic anhydride modified β‐cyclodextrin) hydrogels (poly(NIPAM‐co‐MAH‐β‐CD)) and TiO2 doped with multiwalled carbon nanotubes (TiO2‐MWCNTs) were prepared by an aqueous solution polymerization method with N,N′‐methylenebisacrylamide as crosslinker, potassium persulfate as initiator, NIPAM and MAH‐β‐CD as monomers, and TiO2‐MWCNTs as functional filler. The structure and properties of the as‐prepared thermosensitive composites were characterized with FTIR, XRD, XPS, TEM, BET, and UV‐vis diffuse reflectance spectroscopy. The thermoresponsive property of the composites prepared under various synthesis conditions was investigated using equilibrium swelling ratio measurements at temperatures ranging from 20 to 45°C. The swelling mechanism and kinetics of the composites were determined by analyzing the rate of swelling. The photocatalytic behavior of the thermosensitive composites was evaluated from the extent of removal of methyl orange (MO) from solutions under solar light irradiation. It was found that the thermosensitive composites have better removal efficiency of MO than pure TiO2. The thermosensitive composites exhibited easy separation and less deactivation after several runs. The advantages of the thermosensitive composites revealed its great practical potential in wastewater treatment. POLYM. COMPOS., 2013. © 2013 Society of Plastics Engineers
Novel polyfuran/functionalized multiwalled carbon nanotubes composites with improved conductivity: Chemical synthesis, characterization, and antioxidant activity
Authors: Zare Ehsan Nazarzadeh , Lakouraj Moslem Mansour , Moghadam Peyman Najafi , Azimi Razieh
Published: March 2013

Novel composites containing very small quantities of functionalized multiwalled carbon nanotubes (MWCNTs‐COOH; 0.025, 0.050, and 0.075 g), and furan were synthesized via in situ chemical oxidative polymerization. The polymerization was carried out in nitromethane at room temperature using anhydrous iron (III) chloride (FeCl3) as an oxidant. The nanocomposites were characterized by Fourier transform infrared, ultraviolet–visible, X‐ray diffraction, differential scanning calorimetry, and field emission scanning electron microscopy. All synthesized composites were crystalline and showed good solubility in dimethyl sulfoxide and N‐methyl 2‐pyrrolidone. The conductivity of composites was measured with a four‐probe method, and it was found that the electrical conductivity increased by increasing the amount of MWCNTs‐COOH. The maximum electrical conductivity value (6.68 × 10−4 S cm−1) was obtained for polyfuran/MWCNTs‐COOH (1:0.075, v/w). The resulting composites were analyzed for their antioxidant activity using 2,2‐diphenyl‐1‐picrylhydrazyl assay. The results showed that the antioxidant activity of the composites increased by increasing the amount of MWCNTs‐COOH in nanocomposite. POLYM. COMPOS., 2013. © 2013 Society of Plastics Engineers
Diffusion of solvents in poly(vinyl acetate) and partially and fully hydrolyzed poly(vinyl alcohol)
Authors: Zielinski John M. , Hamedi Mourad , Balashova Ida M. , Danner Ronald P.
Published: March 2013

Diffusivities of methyl acetate, methanol and water in poly(vinyl acetate) and fully and partially hydrolyzed poly(vinyl alcohol) have been measured by capillary column inverse gas chromatography and/or gravimetric sorption. Data from the literature have been used when available for comparison. Overall the diffusivities show good consistency in terms of their temperature and concentration dependences. The free‐volume model has been applied to all the data with excellent results. In most cases the dramatic changes in diffusivities with temperature and concentration can be captured using only a few experimental data points and two regression parameters. This demonstrates that the free‐volume theory is a valuable tool for the design of equipment for processing and devolatilization of polymer − solvent systems. © 2013 Society of Chemical Industry
Targeting human serum fucome by an integrated liquid‐phase multicolumn platform operating in “cascade” to facilitate comparative mass spectrometric analysis of disease‐free and breast cancer sera
Authors: Selvaraju Subhashini , Rassi Ziad El
Published: March 2013

A fully integrated platform was developed for capturing/fractionating human fucome from disease‐free and breast cancer sera. It comprised a multicolumn operated by HPLC pumps and switching valves for the simultaneous depletion of high abundance proteins via affinity‐based subtraction and the capturing of fucosylated glycoproteins via lectin affinity chromatography followed by the fractionation of the captured glycoproteins by reversed phase chromatography (RPC). Two lectin columns specific to fucose, namely Aleuria aurantia lectin (AAL) and Lotus tetragonolobus agglutinin (LTA) were utilized. The platform allowed the “cascading” of the serum sample from column‐to‐column in the liquid phase with no sample manipulation between the various steps. This guaranteed no sample loss and no propagation of experimental biases between the various columns. Finally, the fucome was fractionated by RPC yielding desalted fractions in volatile acetonitrile‐rich mobile phase, which after vacuum evaporation were subjected to trypsinolysis for LC‐MS/MS analysis. This permitted the identification of the differentially expressed proteins (DEP) in breast cancer serum yielding a broad panel of 35 DEP from the combined LTA and AAL captured proteins and a narrower panel of eight DEP that were commonly differentially expressed in both LTA and AAL fractions, which are considered as more representative of cancer altered fucome.
Direct observation of morphological development during the spin‐coating of polystyrene–poly(methyl methacrylate) polymer blends
Authors: Toolan Daniel T. W. , Haq Ehtsham ul , Dunbar Alan , Ebbens Stephen , Clarke Nigel , Topham Paul D. , Howse Jonathan R.
Published: March 2013

We present results of the direct observation, in real‐space, of the phase separation of high molecular weight polystyrene and poly(methyl methacrylate) fromortho‐xylene using our newly developed technique of high speed stroboscopic interference microscopy. Taking a fixed concentration (3 wt % ino‐xylene) at a fixed composition (1:4 by weight) and by varying the rotational rate during the spin‐coating process, we are able to observe the formation of a range of phase separated bicontinuous morphologies of differing length‐scales. Importantly, we are able to show that the mechanism by which the final phase separated structure is formed is through domain coarsening when rich in solvent, before vitrification occurs and fixes the phase separated structure. The ability to directly observe morphological development offers a route toward controlling the length‐scale of the final morphology through process control andin situfeedback, from a single stock solution. © 2013 Wiley Periodicals, Inc. J. Polym. Sci., Part B Polym. Phys. 2013, 51, 875–881
Using proteomics to uncover extracellular matrix interactions during cardiac remodeling
Authors: Patterson Nicolle L. , Iyer Rugmani Padmanabhan , de Castro Brás Lisandra E. , Li Yaojun , Andrews Thomas G. , Aune Gregory J. , Lange Richard A. , Lindsey Merry L.
Published: March 2013

The left ventricle (LV) responds to a myocardial infarction with an orchestrated sequence of events that result in fundamental changes to both the structure and function of the myocardium. This collection of responses is termed as LV remodeling. Myocardial ischemia resulting in necrosis is the initiating event that culminates in the formation of an extracellular matrix (ECM) rich infarct scar that replaces necrotic myocytes. While the cardiomyocyte is the major cell type that responds to ischemia, infiltrating leukocytes and cardiac fibroblasts coordinate the subsequent wound healing response. The matrix metalloproteinase family of enzymes regulates the inflammatory and ECM responses that modulate scar formation. Matridomics is the proteomic evaluation focused on ECM, while degradomics is the proteomic evaluation of proteases as well as their inhibitors and substrates. This review will summarize the use of proteomics to better understand matrix metalloproteinase roles in post myocardial infarction LV remodeling.
Rapid high‐yield N‐acylation of aminothiols: N‐acetylglutathione and N‐acetylhomocysteine and their thiol pKa values
Authors: Shen Biao , Bazin Cynthia , English Ann M.
Published: March 2013

Methodology for the rapid N‐acylation of aminothiols in aqueous solution using procedures commonly employed in biochemical studies is described here. Glutathione disulfide (GSSG) and homocystine were diN‐acetylated in ~100% yield in 0.1 M aqueous NaHCO3 (pH 8.5) at room temperature by 2.5 equiv of the activated ester, N‐hydroxysulfosuccinimidyl acetate, an efficient water‐soluble acetylating reagent. Following acetone precipitation, diN‐acetylGSSG was further purified and desalted on a strong anion‐exchange (SAX) cartridge. DiN‐acetylhomocystine was simultaneously purified and desalted on a C18 cartridge. The N‐acetylated aminothiols were generated using gel‐immobilized tris(2‐carboxyethyl)phosphine as a reductant, which obviated the need for further purification. Alternatively, disulfide exchange with dissolved dithiothreitol yielded N‐acetylglutathione, which was purified on the SAX cartridge. pH titrations of N‐acetylglutathione (8.99) and N‐acetylhomocysteine (9.66) as well as those of commercially available N‐acetylcysteine (9.53) and N‐acetylpenicillamine (10.21) yielded pKa(SH) values of importance for biological studies. Copyright © 2013 European Peptide Society and John Wiley & Sons, Ltd.
Rechnerischer Nachweis gußeiserner Hohlsäulen unter Brandbelastung
Authors: Käpplein R. , Frey A.
Published: March 2013

Etwa mit Ausgang des 18. Jahrhunderts ist im Bauwesen ein rasant zunehmender Bedarf an Eisen zu verzeichnen. Relativ rasch entstanden Konstruktionen, in denen zunächst hölzerne Stützen, bald auch Deckenbalken durch entsprechende gußeiserne Bauteile ersetzt wurden, um die Brandgefahr zu mindern. Heute bereitet bei Baumaßnahmen an diesen alten Konstruktionen die brandschutztechnische Beurteilung von Gußsäulen immer wieder Probleme. Einerseits sorgen nach wie vor kursierende Schilderungen von unkontrollierbarem Tragverhalten bzw. schlagartigem Versagen gußeiserner Säulen unter Brandbeanspruchung für Verunsicherung. Andererseits werden erst seit einigen Jahren Grundlagen für eine fundierte Beurteilung des Tragverhaltens unter Brandbelastung erarbeitet. Die hier zugrunde liegenden Untersuchungen hatten das Ziel, gesicherte brandschutztechnische Beurteilungskriterien und Bemessungsregeln für Gußsäulen zu erarbeiten und daraus Vorgaben für die Praxis hinsichtlich der Einstufung dieser Bauteile in Feuerwiderstandsklassen nach DIN 4102, Teil 2, abzuleiten. Analog dem Nachweis der Tragfähigkeit in kaltem Zustand wurden Grundlagen entwickelt, mit denen auch unter Brandeinwirkung die maßgeblichen Bauteilparameter ‐ Geometrie und mechanisch‐technologische Werkstoffeigenschaften ‐ in die Nachweise einbezogen werden können. Mit dem vorgestellten Konzept wird es möglich, entweder die Feuerwiderstandsdauer einer Säule bei vorgegebener Last oder die zulässige Last für eine geforderte Feuerwiderstandsdauer zutreffend abzuschätzen. Der Vergleich rechnerischer Resultate mit Ergebnissen aus Bauteilversuchen bescheinigt dem Konzept eine gute Aussagekraft. Damit steht eine für die praktische Arbeit taugliche Grundlage zur Verfügung.
Technisches Informationssystem zur Planung und Instandhaltung der Wuppertaler Schwebebahn (Teil 1)
Authors: Bremer L. , Bermel A. , Weber B.
Published: March 2013

Die Baumaßnahmen zur Erneuerung aller Tragkonstruktionen der Wuppertaler Schwebebahn sind eine hohe Herausforderung für alle Planungsbeteiligte. 468 Brücken und ebensoviele Stützen sowie 18 Haltestellen werden gänzlich erneuert. Mit dem konsequenten Einsatz integrationsfähiger Softwarelösungen werden die Bereiche Planung, statische Berechnung und Nachweisführung, Konstruktion und Fertigung sowie Instandhaltung automatisiert. In diesem Sinne entstand TIP/WSW Schweb, ein Technisches Informationssystem, das in seiner konsequent objektorientierten Konzeption richtungsweisend für zukünftige Projektplanung sein kann. Die Gesamtkonzeption von TIP/WSW Schweb wird in zwei Teilen dargestellt: Teil I erläutert die Gründe zur Erstellung von TIP/WSW Schweb und dessen hinterlegte Modellstrukturen. Teil II behandelt Teilleistungen von TIP/WSW Schweb in den Bereichen "Statische Modellbildung und Nachweisführung" sowie "Konstruktionsmodellierung und ‐detaillierung".
Experimentelle Untersuchungen zur Tragfähigkeit von Kopfbolzendübeln mit großen Schaftdurchmessern
Authors: Hanswille G. , Jost K. , Schmitt Ch. , Trillmich R.
Published: March 2013

Auf der Grundlage von Eurocode 4, Teil 1‐1, Abschnitt 10 wurden zehn Push‐Out‐Versuche durchgeführt, um die Tragfähigkeit von Kopfbolzendübeln mit einem Schaftdurchmesser von 25 mm zu ermitteln. Die Auswertung der Versuchsergebnisse wurde gemäß Eurocode 3, Anhang Z durchgeführt und zeigte, daß Kopfbolzendübel mit einem Durchmesser von 25 mm nach Eurocode 4, Teil 1‐1, Abschnitt 6.3.2.1 gemessen werden können
Das Steuerstabsystem Meyer/Wunstorf ‐ Wirkungsweise und Erfahrungen
Authors: Meyer H. , Schubart R.
Published: March 2013

Das Steuerstabsystem Meyer/Wunstorf verteilt die Temperaturdrehungen von Eisenbahnbrücken auf die beiden Brückenenden, so daß bei stählernen Brücken zwischen 60 und 120 m Länge auf den sonst erforderlichen Schienenauszug verzichtet werden kann. Es wird über zwei Großversuche an Eisenbahnbrücken berichtet. Neben der Auswertung der Versuche wird auf Wirkungsweise, Detailausbildung und Berechnung des Steuerstabsystems eingegangen.
Ludwig‐Erhard‐Haus
Authors: Gregull Th.
Published: March 2013

Das Ludwig‐Erhard‐Haus, ein neues Kommunikations‐ und Servicezentrum in Berlin, entstand in den letzten Jahren in zwei Bauphasen in Berlin‐Charlottenburg. Die Haupttragelemente bilden 15 elliptische Stahlbögen mit einer Höhe von bis zu 38,6 m und einer Spannweite von bis zu 61,2 m. Von diesen Bögen werden die neun Obergeschosse über kreuzförmige Stahlquerschnitte abgehangen.
Der neue Fernbahnhof Flughafen Frankfurt am Main
Authors: Binnewies W. , Schmidt St.
Published: March 2013

Die Bahnhofshalle für den viergleisigen ICE‐Bahnhof wird auf einer Fläche von ca. 55 m x 700 m in unmittelbarer Nähe des Flughafens errichtet. Das Dach der Bahnhofshalle stellt eine Plattform dar, auf der in einem späteren zweiten Bauabschnitt verschiedene mehrgeschossige Überbauungsvarianten möglich sind, wobei keine zusätzlichen Verstärkungen im Bahnhofsbereich erforderlich sein werden. Das Haupttragwerk der Plattform besteht aus 43 Stahlfachwerkrahmen, die im Abstand von 15 m angeordnet sind. Sie überbrücken mit einer Spannweite von ca. 50 m Gleise und Bahnsteige. Den oberen Abschluß bildet ca. 13 m über den Gleisen eine 30 cm dicke Stahlbetonverbundplatte. Das fertiggestellte Bauwerk wird über seine gesamte Länge fugenlos sein.
Biegedrillknicknachweis Elastisch‐Plastisch für gewalzte I‐Querschnitte
Authors: Osterrieder P. , Werner F. , Kretschmar J.
Published: March 2013

Der Einsatz des nachweisverfahrens Elastisch‐Plastisch nach DIN 18800 T2 für den Biegedrillknicknachweis Theorie II. Ordnung von Trägern und Stützen erfordert die Bestimmung der plastischen Querschnittstragfähigkeit bei kombinierter Beanspuchung durch Normalkraft, zweiachsige Biegung und Wölbkrafttorsion. Auf der Grundlage des statischen Satzes der Traglasttheorie wird in der vorliegenden Untersuchung ein Verfahren entwickelt, welches für beliebige offene, dünnwandige Querschnitte und Beanspruchungen die plastische Grenztragfähigkeit als Maximum einer linearen Optimierungsaufgabe liefert. Die Nutzung der plastischen Querschnittsreserven führt zu einem ähnlich wirtschaftlichen Bemessungsergebnis wie das vereinfachte Verfahren nach DIN 18800 T2. Anhand praxisrelevanter Beispiele wird gezeigt, daß der Biegedrillknicknachweis nach dem Verfahren Elastisch‐Plastisch, ähnlich dem Nachweis Elastisch‐Elastisch Theorie II. Ordnung unter Verwendung PC‐basierter Berechnungsprogramme universell, übersichtlich, sicher und wirtschaftlich in der Baupraxis einzusetzen ist.
Neubau eines Hangars in Kuala Lumpur unter besonderer Berücksichtigung des Hebevorganges der Dachkonstruktion
Authors: Heilmayer G. , Köppl J.
Published: March 2013

In Rahmen der Bauarbeiten für den Großflughafen Kuala Lumpur wurde auch eine Wartungshalle für Großraumflugzeuge errichtet. Es wird über Planung und Ausführung der Stahlkonstruktion des 200 m x 90 m großen Hangars berichtet. Neben der Darstellung des statischen Gesamtkonzeptes nimmt der Hebevorgang des 2500 t schweren Dachens einen breiten Raum ein. Die Konstruktion wurde am Boden vormontiert und mit Hilfe hydraulischer Hubpressen um 26 m in die endgültige Lage gehoben. Abschließend wird über praktische Erfahrungen während der Arbeiten berichtet.
Praxisgerechte Nachweise zur Trag‐ und Gebrauchsfähigkeit von Sandwichbauteilen
Authors: Berner K.
Published: March 2013

Sandwichbauteile mit dünnen metallischen Deckschichten und einer leichten, wärmedämmenden Kernschicht, z. B. aus Polyurethan‐Hartschaum oder Mineralwolle, werden hauptsächlich als tragende Wand‐ und Dachbauteile eingesetzt. Die einzelnen Schichten der Paneele sind schubsteif miteinander verbunden, so daß insgesamt ein Verbundquerschnitt mit hoher Tragfähigkeit zur Wirkung kommt. Der praxisgerechte Einsatz dieser Bauteile ist in Deutschland durch Allgemeine bauaufsichtliche Zulassungen geregelt, in denen auch die erforderlichen Standsicherheits‐ und Gebrauchsfähigkeitsnachweise angegeben sind. Nachfolgend werden die zugehörigen Grundlagen für die rechnerischen Nachweise nach der Sandwich‐Theorie (nachgiebiger Verbund), auch für die zusätzlich anzusetzenden Einwirkungen aus unterschiedlichen Deckenblechtemperaturen und Kriechen der Kernschicht, auf der Basis von explizit angegebenen Formeln und speziell entwickelten Diagrammen angegeben. Eine praxisnahe Bemessung, jeweils für ein Wand‐ und ein Dachteil, ist als Beispiel dargestellt.
RNA processing and decay in plastids
Authors: Germain Arnaud , Hotto Amber M. , Barkan Alice , Stern David B.
Published: March 2013

Plastids were derived through endosymbiosis from a cyanobacterial ancestor, whose uptake was followed by massive gene transfer to the nucleus, resulting in the compact size and modest coding capacity of the extant plastid genome. Plastid gene expression is essential for plant development, but depends on nucleus‐encoded proteins recruited from cyanobacterial or host‐cell origins. The plastid genome is heavily transcribed from numerous promoters, giving posttranscriptional events a critical role in determining the quantity and sizes of accumulating RNA species. The major events reviewed here are RNA editing, which restores protein conservation or creates correct open reading frames by converting C residues to U, RNA splicing, which occurs both in cis and trans, and RNA cleavage, which relies on a variety of exoribonucleases and endoribonucleases. Because the RNases have little sequence specificity, they are collectively able to remove extraneous RNAs whose ends are not protected by RNA secondary structures or sequence‐specific RNA‐binding proteins (RBPs). Other plastid RBPs, largely members of the helical‐repeat superfamily, confer specificity to editing and splicing reactions. The enzymes that catalyze RNA processing are also the main actors in RNA decay, implying that these antagonistic roles are optimally balanced. We place the actions of RBPs and RNases in the context of a recent proteomic analysis that identifies components of the plastid nucleoid, a protein–DNA complex with multiple roles in gene expression. These results suggest that sublocalization and/or concentration gradients of plastid proteins could underpin the regulation of RNA maturation and degradation. WIREs RNA 2013, 4:295–316. doi: 10.1002/wrna.1161

The authors have declared no conflicts of interest for this article.

This article is categorized under:

RNA Processing > Capping and 5' End Modifications

RNA Processing > 3' End Processing

RNA Turnover and Surveillance > Regulation of RNA Stability

RNA in Disease and Development > RNA in Development
Formal verification of a pervasive messaging system
Authors: Konur Savas , Fisher Michael , Dobson Simon , Knox Stephen
Published: March 2013

As ubiquitous computing becomes a reality, its applications are increasingly being used in business-critical, mission-critical and even in safety-critical, areas. Such systems must demonstrate an assured level of correctness. One approach to the exhaustive analysis of the behaviour of systems is
formal verification
, whereby each important requirement is logically assessed against all possible system behaviours. While formal verification is often used in safety analysis, it has rarely been used in the analysis of deployed pervasive applications. Without such formality it is difficult to establish that the system will exhibit the correct behaviours in response to its inputs and environment. In this paper, we show how model-checking techniques can be applied to analyse the probabilistic behaviour of pervasive systems. As a case study we apply this technique to an existing pervasive message-forwarding system,
Scatterbox
. Scatterbox incorporates many typical characteristics of pervasive systems, such as dependence on sensor reliability and dependence on context. We assess the dynamic temporal behaviour of the system, including the analysis of probabilistic elements, allowing us to verify formal requirements even in the presence of uncertainty in sensors. We also draw some tentative conclusions concerning the use of formal verification for pervasive computing in general.
Dynamicity of J waves during coronary intervention and angiography in a patient with non‐Q inferior myocardial infarction
Authors: Kitazawa Hitoshi , Matsushita Hirooki , Takarada Ken , Oguro Takeo , Satoh Masahito , Aizawa Yoshifusa
Published: March 2013

Slurs or notches at the terminal portion of the QRS complexes are called J waves, which may be associated with myocardial ischemia. We describe our experience with a case of a patient with acute inferior myocardial infarction in whom J waves were observed in the inferior leads with ST‐segment elevation. The coronary artery was completely occluded, and during percutaneous intervention, ST‐segment elevation was normalized first, followed by the disappearance of the J waves after full revascularization. On follow‐up coronary angiography (CAG), the J waves in the inferior leads reappeared during the right CAG. The J waves were associated with an alteration of the electrical axis. J waves developing in association with myocardial ischemia seemed to be more sensitive to ischemia and might represent a depolarization abnormality.