bluuebunny/crossref_metadata_2025 huggingface dataset:
Antimicrobial Activity of Commercially Available Essential Oils Against Streptococcus mutans
Authors: Jawale Bhushan Arun , Chaudhari Lalit Kumar D , Sharma Sheeba , Kumar CD Mounesh , Kulkarni Pooja Adwait
Published: May 2012

Introduction

Many essential oils have been advocated for use in complementary medicine for bacterial and fungal infections. However, few of the many claims of therapeutic efficacy have been validated adequately by either in vitro testing or in vivo clinical trials.

Objective

To study the antibacterial activity of nine commercially available essential oils against Streptococcus mutans in vitro and to compare the antibacterial activity between each material.

Methodology

Nine pure essential oils; wintergreen oil, lime oil, cinnamon oil, spearmint oil, peppermint oil, lemongrass oil, cedarwood oil, clove oil and eucalyptus oil were selected for the study. Streptococcus mutans was inoculated at 37°C and seeded on blood agar medium. Agar well diffusion assay was used to measure antibacterial activity. Zone of inhibition was measured around the filter paper in millimeters with vernier caliper.

Results

Cinnamon oil showed highest activity against Streptococcus mutans followed by lemongrass oil and cedarwood oil. Wintergreen oil, lime oil, peppermint oil and spearmint oil showed no antibacterial activity.

Conclusion

Cinnamon oil, lemongrass oil, cedarwood oil, clove oil and eucalyptus oil exhibit antibacterial property against S. mutans.

Clinical significance

The use of these essential oils against S. mutans can be a viable alternative to other antibacterial agents as these are an effective module used in the control of both bacteria and yeasts responsible for oral infections.

How to cite this article

Chaudhari LKD, Jawale BA, Sharma S, Sharma H, Mounesh Kumar CD, Kulkarni PA. Antimicrobial Activity of Commercially Available Essential Oils Against Streptococcus mutans. J Contemp Dent Pract 2012;13(1):71-74.
Mandibular Reconstruction using AO/ASIF Stainless Steel Reconstruction Plate: A Retrospective Study of 36 Cases
Authors: Reddy V Sridhar , Harsha G , Reddy S Ganesh Kumar , Talasila Sunil , Salaam S Abdus , Srinivasulu M
Published: May 2012

Aim

The study was aimed at esthetic and functional results as well as patient tolerance after reconstruction with reconstruction plate. The follow-up ranged from 1 to 4 years.

Materials and methods

A retrospective study of 36 patients who had mandibular reconstruction with AO/ASIF stainless steel reconstruction plates after oncologic resection was evaluated. The indications and postoperative outcomes were studied.

Results

At the end of study, 24 of 36 patients (67%) still had the plate in place. Around three (8%) plates were fractured. Nine (25%) plates got exposed leading to surgical intervention. Surgical results were satisfying, particularly when looking at delayed healing or long-term tolerance. Esthetic (79% rated results as good or acceptable) and functional results of this reconstruction were satisfying.

Conclusion

We conclude by saying that reconstruction plate provides a solution for safe and rapid mandibular reconstruction for patients with poor prognosis or poor condition. This method also preserves the possibility of secondary reconstruction.

Clinical significance

The reconstruction plate may be a good clinical choice for safe and rapid mandibular reconstruction.

How to cite this article

Harsha G, Reddy SGK, Talasila S, Salaam SA, Srinivasulu M, Reddy VS. Mandibular Reconstruction using AO/ASIF Stainless Steel Reconstruction Plate: A Retrospective Study of 36 Cases. J Contemp Dent Pract 2012;13(1):75-79.
Dimensional Accuracy and Details of the Panoramic Cross-sectional Tomographic Images: An in vitro Study
Authors: Kumar M Ashwini , Mody Bharat , Nair Gopa Kumar R , Surender LR , Gopal S Sujatha , Prasad Ravi Varma KA
Published: May 2012

Introduction

Transversal slicing system (TSS) of Planmeca PM 2002 CC is a tomographic technique which enables us to take cross-sectional views of jaws. Tomographic imaging modalities are commonly applied to acquire cross-sectional images of the jaws for preimplant assessment of bone. Among the available tomographic imaging modalities, panoramic radiography is the most accessible imaging system.

Materials and methods

Study was conducted using 25 mandibles, out of these five were used for linear dimensional accuracy measurement and the rest 20 were utilized to study the details within the mandible. Study was aimed to evaluate dimensional stability in the images using different parameters, such as determination of direction of slice, determination of horizontal and vertical magnification, angular distortion, threedimensional distortion and determination of details.

Results

For the direction of slice and for determination of horizontal and vertical magnification change in + 5° to – 5° was in acceptable limit. In determination of details, it was found that there was great discrepancy in readings given by nonradiologist which offset the mean value which was attributed to lack of training for interpretation of the observers.

Conclusion

99% of the readings were in the clinically acceptable limits.

Clinical significance

The easy availability, use of routine equipment, the low cost, low radiation dose for cross-sectional radiography make the TSS most preferred modality.

How to cite this article

Kumar MA, Mody B, Nair GKR, Surender LR, Gopal SS, Prasad RVKA. Dimensional Accuracy and Details of the Panoramic Cross-sectional Tomographic Images: An in vitro Study. J Contemp Dent Pract 2012;13(1):85-97.
Dental Education: Current Scenario and Future Trends
Authors: Tandon Piyush , Sharma Sheeba , Vijayaraghavan Vasantha , Kumar DRV , Rao Yogesh
Published: May 2012

India has more than 290 dental institutions, producing over 25,000 BDS graduates every year. There are three main characteristics that are shared by any profession. Delivering the best possible education to its students, giving priority to public service over self-interest and enforcing regulations and codes of ethics through self-government. Dentistry in India is currently being challenged to maintain the professionalism. This is partly a result of pressures applied to the educational system. This article discusses some challenges in brief and attempts to attend the challenges in positive manner.

How to cite this article

Sharma S, Vijayaraghavan V, Tandon P, Kumar DRV, Sharma H, Rao Y. Dental Education: Current Scenario and Future Trends. J Contemp Dent Pract 2012;13(1):107-110.
Power-law behavior in millennium climate simulations
Authors: Henriksson S. V. , Räisänen P. , Silen J. , Järvinen H. , Laaksonen A.
Published: May 2012

Abstract. Using a method of discrete Fourier transform with varying starting point and length of time window and the long time series provided by millennium Earth System Model simulations, we get good fits to power laws between two characteristic oscillatory timescales of the model climate: multidecadal (50–80 yr) and El Nino (3–6 yr) timescales. For global mean temperature, we fit β ~ 0.35 in a relation S(f) ~ f−β in a simulation without external climate forcing and β over 0.7 in a simulation with external forcing included. We also fit a power law with β ~ 8 to the narrow frequency range between El Nino frequencies and the Nyquist frequency. Regional variability in best-fit β is explored and the impact of choosing the frequency range on the result is illustrated. When all resolved frequencies are used, land areas seem to have lower βs than ocean areas on average, but when fits are restricted to frequencies below 1/(6 yr), this difference disappears, while regional differences still remain. Results compare well with measurements both for global mean temperature and for the Central England temperature record.
Models of soil organic matter decomposition: the SOILR package, version 1.0
Authors: Sierra C. A. , Müller M. , Trumbore S. E.
Published: May 2012

Abstract. Organic matter decomposition is a very important process within the Earth System because it controls the rates of mineralization of carbon and other biogeochemical elements, determining their flux to the atmosphere and the hydrosphere. SOILR is a modeling framework that contains a library of functions and tools for modeling soil organic matter decomposition under the R environment for computing. It implements a variety of model structures and tools to represent carbon storage and release from soil organic matter. In SOILR organic matter decomposition is represented as a linear system of ordinary differential equations that generalizes the structure of most compartment-based decomposition models. A variety of functions is also available to represent environmental effects on decomposition rates. This document presents the conceptual basis for the functions implemented in the package. It is complementary to the help pages released with the software.
Performance Optimization Program for the Business Community: Combining Executive Coaching and Biofeedback
Authors: Matte Richard , van Otterdijk Mia
Published: May 2012

MATTE Consulting Group has been providing individual and organizational development services for the past 23 years. Two years ago, it was brought to our attention that many of our clients (executives) were looking for tools to better perform under stress. We conducted a thorough search to identify executive coaching programs that integrated biofeedback, as well as studies that demonstrated a return on investment for such programs in the business community. We concluded it was preferable to design our own program and determine, with the help of our long-standing clients, how to ensure its efficacy. We also developed our first MindRoom with the help of a leading biofeedback equipment manufacturer, Thought Technology. We have been successful in assisting numerous individuals as well as complete teams of executives in optimizing their performance. We are now building a business spa, and we will soon start group training (eight people at a time).
Enhancing Neuroplasticity to Improve Peak Performance
Authors: Srinivasan Nidamangala Srinivasa
Published: May 2012

Peak performance appears to emerge from a brain that is both talented in the chosen profession and firmly established in higher values. To the extent one can remain anchored in the higher values of selflessness, peak performances can be maintained. The moment values degrade, even at the level of thoughts and feelings, performance is adversely affected. Higher values could be quantitatively measured in terms of applied neuroscience by sensorimotor rhythm values that appear at CPz (or above the default network in the brain). CPz refers to a location on the scalp, defined by the International 10–20 system, along the midline between central (Cz) and parietal (Pz) vertices. The higher the amplitude of SMR, the greater the self-regulation over one's own default network. This would amount to the individual's staying in a passive listening mode; this allows the real-time input from the environment to trigger action, rather than one's actions being skewed by one's own prerogatives. More critically, interpretations become more sensitive as resources dedicated to perceptions diminish. It has been empirically observed that as the SMR values increase (provided the Z-scores are largely within a normative database with respect to people performing at their peak), people gain regulation, control, and mastery over emotional, executive, and sensory quiescence, respectively. The individual Alpha frequency is also maintained above 8–9 µV in the eyes open condition and task condition, as one improves proficiency even over sensory quiescence. Wellness at the physical, emotional, and intellectual levels is accompanied by enhanced performance at each stage of sustainable growth.
William's Story: A Case Study in Optimal Performance
Authors: Tattenbaum Rae
Published: May 2012

Elites in business, academics, and sports, as well as in the performing and visual arts, seek techniques to dissolve barriers while enhancing innate and developing abilities. This case study illustrates a process that weaves together traditional stress-reduction tools, coaching, mental imagery training, psychology, and psycho-physiological technology and that permits individual clients to perform more efficiently at a higher proficiency.
The Internationalization of BCIA
Authors: Moss Donald , Shaffer Fred , Crawford Judy
Published: May 2012

The Biofeedback Certification International Alliance (BCIA)-Australia has recently become the first fully autonomous affiliate of BCIA, certifying neurofeedback professionals in Australia, with requirements equivalent to those of BCIA. BCIA has also established a worldwide network of professionals, who intermittently meet to promote biofeedback and neurofeedback certification in each national community. BCIA accredits programs providing basic training and continuing education.
Getting off the Bench: EEG and HRV Differences Between Starters and Nonstarters
Authors: Shaw Lindsay , Wilson Vietta , Nihon Stephanie
Published: May 2012

There is a strong interest in what separates top-level performers from those who have yet to achieve the same level, across all performance domains. Advances in psychophysiology give insight into where these differences may lie in the minds and bodies of athletes. The present study compared gymnasts who were selected for the competitive lineup to those who were considered part of the Division I gymnastics beam squad but did not compete. This study compared their initial baselines, their response to heart rate variability and neurofeedback training, and their posttraining levels. Baseline differences existed for self-perception of consistency and confidence. There were no pre or post differences in heart rate variability measures. Sensorimotor rhythm electroencephalography (EEG) biofeedback training was associated with a decline in busy brain waves for the competitors. The competitors also had a lower ratio of intensity (intensity/high alpha) in both the pre- and post-EEG measures.
Expanding Practice from Sport Performance to Physicians as Clients
Authors: Sime Wes
Published: May 2012

This article describes the use of biofeedback interventions with PGA golfers, professional baseball players, and college athletes. The author advocates applying the optimal performance framework beyond the field of sport, to high performers in other areas, including business and medicine. Physicians are in many ways athletes and peak performers, and the outcome of their performance is life or death, recovery or disability. Physicians rarely participate in conventional employee assistance programs or stress debriefing, and would benefit from a wider application of a peak performance approach to their optimal wellness for themselves and their families.
Effects of Prosocial, Neutral, and Violent Video Games on College Students' Affect
Authors: Saleem Muniba , Anderson Craig A. , Gentile Douglas A.
Published: May 2012

Recent research reveals that playing prosocial video games increases prosocial cognitions and helpful behaviors [Gentile el al., 2009; Greitemeyer and Osswald, 2009; 2010; 2011]. These results are consistent with social‐cognitive models of social behavior [e.g., the “General Learning Model,” Buckley and Anderson, 2006]. The social‐cognitive learning models suggest that in addition to influencing cognitions, media content may also influence affect. However, past studies on prosocial video games have failed to find a significant effect on affective measures [Greitemeyer and Osswald, 2010]. The present research examined the effects of prosocial, neutral, and violent video games on state hostility and positive affect. Also examined were moderating effects of trait aggressiveness, trait altruistic helping, and trait egoistic helping. Prosocial games reduced state hostility and increased positive state affect. Violent video games had the opposite effects. These effects were moderated by trait physical aggression. Altruistic participants reported relatively more positive affect and less state hostility. Egoistic participants reported relatively more aggravated and mean feelings. Aggr. Behav. 38:263–271, 2012. © 2012 Wiley Periodicals, Inc.
Asymptotic rejection of nonvanishing disturbances despite plant–model mismatch
Authors: Mullhaupt Ph. , Valentinotti S. , Srinivasan B. , Bonvin D.
Published: May 2012

A direct adaptive control methodology for the rejection of unmeasured nonvanishing disturbances is proposed. The approach uses the framework of polynomial RST controllers and relies on the internal model principle with additional degrees of freedom provided by the Q parametrization. The parameters of the Q polynomial are adapted using minimization of the closed‐loop output error. Asymptotic rejection of unmeasured nonvanishing disturbances is guaranteed under the assumption that the closed‐loop plant remains stable. A simulation example illustrates the theoretical developments. Copyright © 2012 John Wiley & Sons, Ltd.
Fabrication of Responsive, Softening Neural Interfaces
Authors: Ware Taylor , Simon Dustin , Arreaga‐Salas David E. , Reeder Jonathan , Rennaker Robert , Keefer Edward W. , Voit Walter
Published: May 2012

A novel processing method is described using photolithography to pattern thin‐film flexible electronics on shape memory polymer substrates with mechanical properties tailored to improve biocompatability and enhance adhesion between the polymer substrate and metal layers. Standard semiconductor wafer processing techniques are adapted to enable robust device design onto a variety of softening substrates with tunable moduli. The resulting devices are stiff enough (shear modulus of ≈700 MPa) to assist with device implantation and then soften in vivo (≈300 kPa) approaching the modulus of brain tissue (≈10 kPa) within 24 h. Acute in vivo studies demonstrate that these materials are capable of recording neural activity. Softening multi‐electrode arrays offer a highly customizable interface, which can be optimized to improve biocompatibility, enabling the development of robust, reliable neural electrodes for neural engineering and neuroscience.
Peptides as Targeting Elements and Tissue Penetration Devices for Nanoparticles
Authors: Ruoslahti Erkki
Published: May 2012

The use of nanoparticles in medicine (nanomedicine) has recently become an intensely studied field. Nanoparticles carrying drugs and imaging agents have already reached the clinic, but they are essentially passive delivery vehicles, not what are referred to as “smart” nanoparticles. An important function to add to make nanoparticles smarter is active homing to the target tissue. It makes nanoparticles accumulate in the target tissue at higher concentrations than would be the case without this feature, increasing therapeutic efficacy and reducing side effects. This review discusses the recent developments in the nanoparticle targeting field with emphasis on peptides that home to vascular “zip codes” in target tissues and provide a tissue‐ and cell‐penetrating function.
Crop Production Contracts and Marketing Strategies: What Drives Their Use?
Authors: Franken Jason R.V. , Pennings Joost M. E. , Garcia Philip
Published: May 2012

Numerous crop marketing and risk management tools are available. Research relating producers’ risk attitudes to their use of these tools has produced mixed results, and most studies focus on individual tools, neglecting potential complementarities in information they provide. Little is known about the proportion in which individual tools are used, e.g., the percentage of the crop that is forward sold as opposed to hedged. This study identifies factors, including risk attitude, that impact the proportion of corn and soybean producers’ sales through spot markets, futures, and options, as well as forward and production contracts, and investigates contract complementarity and substitutability using survey and accounting data, and causal modeling.
Behavioral Responses of Cao Vit Gibbon (Nomascus Nasutus) to Variations in Food Abundance and Temperature in Bangliang, Jingxi, China
Authors: Fan Peng‐fei , Fei Han‐lan , Ma Chang‐yong
Published: May 2012

The Cao Vit gibbon is a critically endangered species with only about 110 individuals remaining in a degraded karst forest along the China‐Vietnam border. Behavioral data from this site are particularly useful in understanding gibbon behavioral adaptations to different sets of ecological conditions and will contribute to the conservation of the species. We studied seasonal variation in the time budget and diet of the Cao Vit gibbon in response to variation in food availability and ambient temperature by observing two groups for 1,379 hr between January and December 2009. We used 5‐min scan samples to record the activity of gibbons. Both ambient temperature and food availability varied from month to month. Gibbon groups increased resting time and huddled together in sleeping places in cold months. Gibbons spent more time feeding on fruit when fruit was more abundant suggesting that fruit was their preferred food. Alternatively, leaf eating was negatively correlated with leaf availability which suggested that leaves may be used as a fallback food. Gibbons increased their diet diversity when they ate more leaves. This might be a strategy to cope with toxins or digestion inhibitor accumulation associated with feeding from a limited number of leaf species. Individuals consumed more buds when Broussonetia papyrifera produced buds in March and April. During this period, they decreased traveling time and engaged in less frequent social interactions. Gibbons spent more time searching for and feeding on invertebrates during June and October. However, we did not collect data on invertebrate abundance and therefore cannot determine the relationship between invertebrate feeding and availability. We conclude that flexibility in consuming diverse food types and food species, and in responding to the availability of preferred foods, has enabled the Cao Vit gibbon to survive in a degraded karst forest habitat. Am. J. Primatol. 74:632–641, 2012. © 2012 Wiley Periodicals, Inc.
Mechanochemical preparation of devulcanized ground fluoroelastomers for the enhancement of the thermal stability of nitrile–butadiene rubber vulcanizates
Authors: Lu Zhixing , Zhang Xinxing , Tian Dong , Li Hua , Lu Canhui
Published: May 2012

Mechanochemically devulcanized ground fluoroelastomer (FKM) was used as a low‐cost functional additive for the enhancement of the thermal stability of nitrile–butadiene rubber (NBR) vulcanizates. Without the use of any chemicals, the stress‐induced mechanochemical devulcanization of ground FKM was achieved through solid‐state mechanochemical milling at ambient temperature. The sol fraction of the ground FKM was increased from its original 1.4 to 19.8% after milling; this confirmed the realization of the mechanochemical devulcanization of FKM. Moreover, the oxygen‐containing polar groups on the surface of the mechanochemically milled FKM benefitted its interfacial adhesion with the polar NBR matrix. The curing characteristics and mechanical properties of the devulcanized, FKM‐filled NBR vulcanizates were investigated and compared with those of the untreated FKM‐filled NBR vulcanizates. The results show that the mechanical properties of the devulcanized FKM‐filled NBR vulcanizates were much better than those of the untreated FKM‐filled NBR vulcanizates. The presence of the reclaimed FKM significantly increased the onset degradation temperature of the NBR vulcanizates as a result of the improved polymer–filler interaction, uniform dispersion, and high thermal stability of the reclaimed FKM. © 2012 Wiley Periodicals, Inc. J Appl Polym Sci, 2012
The nanocomposites of zinc oxide/L‐amino acid‐based chiral poly(ester‐imide) via an ultrasonic route: Synthesis, characterization, and thermal properties
Authors: Mallakpour Shadpour , Zeraatpisheh Fatemeh
Published: May 2012

In this investigation, a chiral poly) ester‐imide) (PEI) via direct polyesterification of N,N′‐(pyromellitoyl)‐bis‐(L‐tyrosine dimethyl ester) and N‐trimellitylimido‐L‐methionine was prepared using the tosyl chloride/pyridine/N,N′‐dimethylformamide system as a condensing agent. This approach allows the insertion of two natural amino acids into the polymer backbone and the creation of a bioactive polymer. From the chemical point of view, the ester groups impart to the polymer's main and side chain increased sensibility to hydrolysis that can cause chain breaking. Therefore, this polymer is expected to be biodegradable and could be classified as an eco‐friendly polymer. The polymer also had a useful level of thermal stability associated with excellent solubility. PEI/zinc oxide bionanocomposites were subsequently prepared by an ultrasonic method as a simple and inexpensive route, using ZnO nanoparticles (ZnO‐NPs) modified by 3‐aminopropyltriethoxylsilane (KH550) as a coupling agent. The structure and properties of the obtained BNC polymers were confirmed by Fourier transform infrared spectroscopy, X‐ray diffraction, field emission scanning electron microscopy (FE‐SEM), transmission electron microscopy (TEM), and thermogravimetric analysis (TGA). The direct proofs for the formation of the true BNC polymers were provided by TEM. Also, the morphology study of the synthesized polymer‐based BNCs showed well‐dispersed ZnO‐NPs in the polymer matrix by FE‐SEM analysis. TGA studies indicated that an increase of the NP content led to an enhancement of the thermal stability of the new BNC polymers. © 2012 Wiley Periodicals, Inc. J Appl Polym Sci, 2012
Study on molding process of UHMWPE microporous filter materials
Authors: Zhang Qiang , Jia Mingyin , Xue Ping
Published: May 2012

A method called loose sintering was first introduced to prepare ultrahigh‐molecular weight polyethylene (UHMWPE) microporous materials. The pore size was predicted by the face‐centered cubic structure model while considering the particles' arrangement and melt. The results showed that the experimental pore diameter was close to that calculated by the present model. The effects of UHMWPE molecular weight, particle diameter, packing density, sintering temperature, and sintering time on pore size, compressive strength, pore diameter distribution, and density were presented. The morphology of micropore and the uniformity of pore distribution were analyzed by scanning electron microscopy and fractal geometry. The results showed that average pore diameter and porosity both increased with the UHMWPE particle diameter while decreased with compressive strength and bulk density. Sintering temperature and sintering time determined whether the heat was redundant to melt the particles. They also determined the pore size and the uniformity. UHMWPE microporous materials could be successfully prepared with suitable processing conditions. © 2012 Wiley Periodicals, Inc. J Appl Polym Sci, 2012
Molecular network development and evolution of nanoscale morphology in an epoxy‐amine thermoset polymer
Authors: Sahagun Christopher M. , Knauer Katrina M. , Morgan Sarah E.
Published: May 2012

Epoxy‐amine thermoset polymers exhibit a complicated, highly crosslinked network structure. The connectivity of this network drives material parameters such as mechanical properties and solvent permeation. Understanding the molecular network architecture is also an important aspect of the developing realistic network topologies for use in molecular dynamic simulations. Here, the evolution of network connectivity in a typical crosslinked epoxy‐amine network (Epon 828/3‐aminophenyl sulfone) is monitored as a function of cure time. Special attention is paid to nanoscale variation in the crosslink density of the network. Submicron atomic force microscope images of sample fracture surfaces revealed three distinct types of crack tip propagation. Near‐infrared spectroscopy, rheological and thermal characterization were used to correlate each type of fracture propagation behavior to a different stage of network development. Monitoring changes in the nanoscale fracture behavior reveals information regarding changes in the network architecture during cure and provides insight into the final structure of the epoxy‐amine network. © 2012 Wiley Periodicals, Inc. J Appl Polym Sci, 2012
Dynamic mechanical properties for polyurethane elastomers applied in elastomeric mortar
Authors: Rocco José Atílio Fritz Fidel , Lima José Eduardo Salgueiro , Lourenço Vera Lúcia , Batista Natássia Lona , Botelho Edson Cocchieri , Iha Koshun
Published: May 2012

Dynamic mechanical properties of a polyurethane (PU) elastomer and a mortar processed with the same elastomer (modified polytetramethylene ether glycol (PTMEG)) were studied. The results obtained showed that the liquid aromatic amine ETHACURE® 300, used as cure agent, can be used to substitute the aromatic amine MOCA®, which is usually used as cure agent in high performance elastomers. The resulting mortar produced with ETHACURE® 300 presents similar dynamic‐mechanical thermal properties when compared with MOCA ®. However, dynamic‐mechanical thermal analysis studies showed that the mortar developed with ETHACURE® 300 presents some advantages such as the low values of tan δ, indicating a good capacity of recovery of the strain after retreating an applied force. © 2012 Wiley Periodicals, Inc. J Appl Polym Sci, 2012
Monodisperse‐porous N‐methyl‐D‐glucamine functionalized poly(vinylbenzyl chloride‐co‐divinylbenzene) beads as boron selective sorbent
Authors: Samatya Saba , Kabay Nalan , Tuncel Ali
Published: May 2012

To generate a new sorbent with high boron adsorption capacity, we synthesized monodisperse‐porous poly(vinylbenzyl chloride‐co‐divinylbenzene), poly(VBC‐co‐DVB), beads 8.5 μm in size by a new “modified seeded polymerization” technique. By using their chloromethyl functionality, the beads were derivatized by a simple, direct reaction with a boron‐selective ligand, N‐methyl‐D‐glucamine (NMDG). The selection of poly(VBC‐co‐DVB) beads as a starting material allowed to obtain high boron sensitive‐ligand density on the beads depending on their high chloromethyl content. In the batch adsorption runs performed using NMDG‐attached poly(VBC‐co‐DVB) beads as sorbent, boron removal was efficiently performed in a wide pH range between 4 and 11. Quantitative boron removal was observed with the sorbent concentration of 4 g/L. In the same runs, plateau value of equilibrium adsorption isotherm was obtained as 14 mg boron/g beads. Relatively higher boron adsorption was explained by high ligand density and high specific surface area of the sorbent. Boron adsorption isotherms were analyzed using Langmuir and Freundlich models. In the kinetic runs performed for boron removal, the equilibrium was attained within 10 min at a value of 98%. The fast kinetic behavior was explained by the smaller particle size and enhanced porosity of the new sorbent. Infinite solution volume model and unreacted core model were used to evaluate boron adsorption onto the NMDG‐attached poly(VBC‐co‐DVB) beads. The results indicated that the adsorption process is controlled by the particle‐diffusion step. © 2012 Wiley Periodicals, Inc. J Appl Polym Sci, 2012
Characterization of polyvinyl chloride/polyethyl methacrylate polymer blend for use as polymer host in polymer electrolytes
Authors: Zakaria N. A. , Isa M. I. N. , Mohamed N. S. , Subban R. H. Y.
Published: May 2012

Polyvinyl chloride (PVC) and polyethyl methacrylate (PEMA) were used to prepare polymer blends for use in solid polymer electrolyte. Dynamic mechanical analysis showed that both the storage modulus (E') and the glass transition temperature (Tg) of the PVC/PEMA blend are intermediate between those of the two component polymers. Scanning electron microscopy proved that addition of PEMA into PVC changed the morphology of the blends. The shifts in Fourier transform infrared bands and X‐ray diffraction peaks together with the presence of a single Tg suggest that the blends are partially miscible. The blend with 35 wt % PEMA seems to be the most suitable candidate for use as polymer host in polymer electrolyte, because it has the most suitable mechanical property and is the most amorphous blend system. This blend system also has the highest room temperature conductivity value of 4.74 × 10−10 S cm−1 amongst other blend systems. © 2012 Wiley Periodicals, Inc. J Appl Polym Sci, 2012
Investigating the self healing process on coated steel by SVET and EIS techniques
Authors: Neema S. , Selvaraj M. , Raguraman J. , Ramu S.
Published: May 2012

Microencapsule was incorporated into an interpenetrating polymer network and applied over steel surface. A scratch was made on the coated surface and its self healing ability was studied using scanning vibrating electrode technique (SVET) and electrochemical impedance spectroscopy (EIS). Results of SVET studies show that the current density increases in the initial stage. After 24 h, the current density decreases, which indicating the formation of passive polymer film due to the diffusion of core polymer present in the microcapsules through the holidays. Increase in the resistance (107 Ω/cm2) of the self healing coating was observed after 24 h in EIS studies confirming the formation of the passive film. The results of the studies are discussed in this article. © 2012 Wiley Periodicals, Inc. J. Appl. Polym. Sci., 2013
Microstructural characterization of corn starch‐based porous thermoplastic composites filled with multiwalled carbon nanotubes
Authors: Yurdakul Hilmi , Durukan Oya , Seyhan A. Tugrul , Celebi Hande , Oksuzoglu Mustafa , Turan Servet
Published: May 2012

Microstructural characterization of corn starch‐based porous thermoplastic (TPS) composites containing various contents (0.1, 0.5, and 1 wt %) of multiwalled carbon nanotubes (MWCNTs) was performed. Corn starch was plasticized with a proper combination of glycerol and stearic acid. TPS composites with MWCNT were prepared conducting melt extrusion followed by injection molding. TPS containing 1 wt % of MWCNTs exhibited higher tensile strength and elastic modulus values than neat TPS. Moreover, TPS electrical conductivity was determined to increase with increasing content of MWCNTs. X‐ray diffraction measurements revealed that incorporation of MWCNTs increased the degree of TPS crsystallinity to some extent. Scanning electron microscopy examination revealed that MWCNT altered TPS surface morphology and tensile failure modes, significantly. Transmission electron microscopy investigation showed that dispersion characteristics of MWCNTs within TPS were in the form of tiny clusters around micro pores of TPS, which is considered influential on electrical conductivity of the resulting composites. © 2012 Wiley Periodicals, Inc. J. Appl. Polym. Sci., 2013
Grafting of poly(vinyl alcohol) on natural rubber latex particles
Authors: Wongthep W. , Srituileong S. , Martwiset S. , Amnuaypanich S.
Published: May 2012

Poly(vinyl alcohol) (PVA) was grafted on natural rubber (NR) latex particles (NR‐g‐PVA) using potassium persulfate to generate active radicals on both NR particle surface as well as PVA molecules. 1H‐ and 13C‐nuclear magnetic resonance spectroscopy suggested a possibly chemical attachment of PVA on the NR. The amount of graft‐PVA expressed in term of grafting percentage (%G) increased almost linearly with the amount of PVA adding to the NR latex. Measuring by dynamic light scattering, the particle size of NR‐g‐PVA particles was larger than the size of unmodified NR, also it increased with the molecular weight and %G of PVA. Transmission electron microscopy images of the NR‐g‐PVA latex particles revealed that the size of PVA‐grafted NR particle was enlarged by a layer of graft‐PVA surrounding the NR particle. Given by the graft‐PVA layer surrounding NR particles, the NR‐g‐PVA latex particles possessed better colloidal stability as lowering pH compared with the unmodified NR latex. Comparing with unmodified NR particles, the electrophoretic mobility of NR‐g‐PVA particles was lower due to the presence of graft‐PVA that shifted the shear plane further away from the surface of the particles. © 2012 Wiley Periodicals, Inc. J. Appl. Polym. Sci., 2013
Analysis of Dental Root Apical Morphology: A New Method for Dietary Reconstructions in Primates
Authors: Hamon NoÉmie , Emonet Edouard‐Georges , Chaimanee Yaowalak , Guy Franck , Tafforeau Paul , Jaeger Jean‐Jacques
Published: May 2012

The reconstruction of paleo‐diets is an important task in the study of fossil primates. Previously, paleo‐diet reconstructions were performed using different methods based on extant primate models. In particular, dental microwear or isotopic analyses provided accurate reconstructions for some fossil primates. However, there is sometimes difficult or impossible to apply these methods to fossil material. Therefore, the development of new, independent methods of diet reconstructions is crucial to improve our knowledge of primates paleobiology and paleoecology. This study aims to investigate the correlation between tooth root apical morphology and diet in primates, and its potential for paleo‐diet reconstructions. Dental roots are composed of two portions: the eruptive portion with a smooth and regular surface, and the apical penetrative portion which displays an irregular and corrugated surface. Here, the angle formed by these two portions (aPE), and the ratio of penetrative portion over total root length (PPI), are calculated for each mandibular tooth root. A strong correlation between these two variables and the proportion of some food types (fruits, leaves, seeds, animal matter, and vertebrates) in diet is found, allowing the use of tooth root apical morphology as a tool for dietary reconstructions in primates. The method was then applied to the fossil hominoid Khoratpithecus piriyai, from the Late Miocene of Thailand. The paleo‐diet deduced from aPE and PPI is dominated by fruits (>50%), associated with animal matter (1–25%). Leaves, vertebrates and most probably seeds were excluded from the diet of Khoratpithecus, which is consistent with previous studies. Anat Rec, 2012. © 2012 Wiley Periodicals, Inc.
SEQUENCING AND CHARACTERIZATION OF GLYCOGEN SYNTHASE AND GLYCOGEN PHOSPHORYLASE GENES FROM Spodoptera exigua AND ANALYSIS OF THEIR FUNCTION IN STARVATION AND EXCESSIVE SUGAR INTAKE
Authors: Tang Bin , Xu Qi , Zou Qi , Fang Qi , Wang Shigui , Ye Gongyin
Published: May 2012

Glycogen and trehalose are important energy source and key regulation factors in the development of many organisms’ pass through energy metabolism, including bacteria, fungi, and insects. To study glycogen metabolism pathway in Spodoptera exigua, first cDNAs for glycogen synthase (SpoexGS) and glycogen phosphorylase (SpoexGP) were cloned from S. exigua. SpoexGS cDNA contains an open reading frame of 2,010 nucleotides encoding a protein of 669 amino acids with a predicted molecular mass of 76.19 kDa and a pI of 5.84. SpoexGP contains an open reading frame of 2,946 nucleotides, which encodes a protein of 841 amino acids with a predicted molecular mass of approximately 96.63 kDa and a pI of 6.03. Second, Northern blotting revealed that SpoexGS and SpoexGP mRNAs were expressed in brain, fat body, mid‐gut, Malpighian tubules, spermary, and tracheae of S. exigua. Expression patterns for SpoexGS and SpoexGP mRNAs were similar in fat body, but differed in whole body at different developmental stages. The last, under starvation conditions, SpoexGS and SpoexGP transcript expression rapidly decreased with increasing starvation time. When the starvation stress was removed, SpoexGS and SpoexGP mRNA levels were lower in the groups starved for 6 and 12 h than in the 24‐h starvation and control groups. Treatment with excessive sugar intake led to higher levels of SpoexGS and SpoexGP transcripts after 12 h compared to the control group. These findings provide new data on the tissue distribution, expression patterns, and potential function of glycogen synthase and glycogen phosphorylase proteins. © 2012 Wiley Periodicals, Inc.
Cyp15F1: A NOVEL CYTOCHROME P450 GENE LINKED TO JUVENILE HORMONE‐DEPENDENT CASTE DIFFERENTION IN THE TERMITE Reticulitermes flavipes
Authors: Tarver Matthew R. , Coy Monique R. , Scharf Michael E.
Published: May 2012

Termites are eusocial insects that jointly utilize juvenile hormone (JH), pheromones, and other semiochemicals to regulate caste differentiation and achieve caste homeostasis. Prior EST sequencing from the symbiont‐free gut transcriptome of Reticulitermes flavipes unexpectedly revealed a number of unique cytochrome P450 (Cyp) transcripts, including fragments of a Cyp15 family gene (Cyp15F1) with homology to other insect Cyp15s that participate in JH biosynthesis. The present study investigated the role of Cyp15F1 in termite caste polyphenism and specifically tested the hypothesis that it plays a role in JH‐dependent caste differentiation. After assembling the full‐length Cyp15F1 cDNA sequence, we (i) determined its mRNA tissue expression profile, (ii) investigated mRNA expression changes in response to JH and the caste‐regulatory primer pheromones γ‐cadinene (CAD) and γ‐cadinenal (ALD), and (iii) used RNA interference (RNAi) in combination with caste differentiation bioassays to investigate gene function at the phenotype level. Cyp15F1 has ubiquitous whole‐body expression (including gut tissue); is rapidly and sustainably induced from 3 h to 48 h by JH, CAD, and ALD; and functions at least in part by facilitating JH‐dependent soldier caste differentiation. These findings provide the second example of a termite caste regulatory gene identified through the use of RNAi, and significantly build upon our understanding of termite caste homeostatic mechanisms. These results also reinforce the concept of environmental caste determination in termites by revealing how primer pheromones, as socioenvironmental factors, can directly influence Cyp15 expression and caste differentiation.
Dual‐Acting Diether Derivatives of Piperidine and Homopiperidine with Histamine H3 Receptor Antagonistic and Anticholinesterase Activity
Authors: Bajda Marek , Kuder Kamil J. , Łażewska Dorota , Kieć‐Kononowicz Katarzyna , Więckowska Anna , Ignasik Michalina , Guzior Natalia , Jończyk Jakub , Malawska Barbara
Published: May 2012

The study presents novel biological properties of diether derivatives of homo‐ or substituted piperidine ligands of the histamine H3 receptor. The compounds were evaluated for their inhibitory potency against acetylcholinesterase (AChE) from the electric eel and butyrylcholinesterase (BuChE) from horse serum. The most interesting multifunctional compound 13 displayed high affinity for the cloned hH3R (Ki = 3.48 nM) and moderate inhibitory potency against both enzymes (IC50 AChE = 7.91 µM and BuChE = 4.97 µM). Molecular modeling studies revealed interactions with key amino acid residues in the homology model of histamine H3 receptor ligands, as well as the binding model for AChE and BuChE in the catalytic and peripheral active sites.
Proteolytic inactivation of α1‐antitrypsin and α1‐antichymotrypsin by neutrophils in arthritic joints
Authors: Abbink Jannie J. , Kamp Angela M. , Nuijens Jan H. , Swaak Tom J. G. , Hack C. Erik
Published: May 2012

Objective. In vitro, activated neutrophils create a microenvironment in which proteinase inhibitors are inactivated through the coordinate action of reactive oxygen species and released elastase. We investigated whether such a mechanism may contribute to the destruction of the joint tissues in arthritis.

Methods. We analyzed the state of α1‐antitrypsin (α1AT) and α1‐antichymotrypsin (α1ACT), the two major inhibitors of the neutrophilic serine proteinases, in synovial fluid (SF) from patients with inflammatory arthropathies (n = 71) and osteoarthritis (OA) (n = 11), and related the results to neutrophil activation in SF.

Results. The ratio of functional to antigenic levels of α1AT in SF of patients with inflammatory joint diseases was similar to that of α1AT in normal plasma, whereas that of α1ACT was significantly decreased. Patients with inflammatory arthropathies had significantly higher levels of inactivated α1AT (iα1AT) and inactivated α1ACT (iα1ACT) in SF (as determined with monoclonal antibodies specific for the inactivated [i.e., proteolytically inactivated and/or complexed] forms of these inhibitors) than patients with OA (P < 0.005). Inactivated α1AT and iα1ACT levels corresponded to 0.3–11% and 3–99%, respectively, of the total amount of these inhibitors in SF. Most of the iα1AT in SF had a lower Mr than that of native α1AT. Inactivated α1ACT in SF had an Mr identical to that of nonfunctional α1ACT in plasma treated with chymotrypsin. Levels of both iα1AT and iα1ACT correlated significantly with lactoferrin and elastase levels.

Conclusion. These results suggest that α1AT and α1ACT in arthritic joints are inactivated in part by activated neutrophils, suggesting a role for these cells in impairment of the local balance between proteinases and their inhibitors in arthritis.
Metalloproteinases, tissue inhibitor, and proteoglycan fragments in knee synovial fluid in human osteoarthritis
Authors: Lohmander L. Stefan , Hoerrner Lori A. , Lark Michael W.
Published: May 2012

Objective. To determine the concentrations of human stromelysin‐1, collagenase, tissue inhibitor of metalloproteinases (TIMP), and proteoglycan fragments in knee synovial fluid in patients with injury to the meniscus or anterior cruciate ligament, posttraumatic osteoarthritis, primary osteoarthritis, or pyrophosphate arthritis.

Methods. Synovial fluid samples were collected from patients with knee disease diagnosed arthroscopically and radiologically. Concentrations of stromelysin‐1, collagenase, and TIMP‐1 were determined by sandwich immunoassay, using monoclonal and polyclonal antibodies. Fragments of cartilage proteoglycan containing the chondroitin sulfate‐binding region were determined by immunoassay with a polyclonal antibody.

Results. Average concentrations of metalloproteinases, TIMP, and proteoglycan fragments in joint fluid were significantly elevated in patients from all disease groups as compared with volunteers with healthy knees (reference group). Stromelysin concentrations in disease groups averaged 15–45 times that of the reference group. The molar ratios between stromelysin and collagenase varied between 10 and 150. The molar ratio between total stromelysin and free TIMP was 0.5 in the reference group and between 1.6 and 5.3 in the disease groups.

Conclusion. Stromelysin concentration in joint fluid is a parameter that distinguishes diseased joints from healthy joints, with a sensitivity of 84% and a specificity of 90%. The high concentrations of metalloproteinase relative to TIMP in joint fluid from patients with the conditions studied may be associated with cartilage matrix degradation in these arthritides.
Increased levels of IgA antibodies to cytokeratin‐18 and epidermal keratin in rheumatoid arthritis
Authors: Borg A. A. , Dawes P. T. , Mattey D. L.
Published: May 2012

Objective. To investigate whether levels of antibodies to cytokeratin‐18 (CK‐18) and epidermal keratin (EPK) were raised in patients with rheumatoid arthritis (RA).

Methods. We measured antibodies to CK‐18 and EPK in patients with RA and in patients with osteoarthritis (OA), as well as in normal control subjects by means of an enzyme‐linked immunosorbent assay.

Results. IgA antibodies to both CK‐18 and EPK were significantly increased in patients with RA compared with the controls and with patients with OA (P < 0.0001). No difference was noted in the levels of IgG or IgM antibodies to CK‐18 or EPK between controls and patients with OA or RA.

Conclusion. Raised levels of IgA autoantibody to CK‐18 and EPK may reflect damage to cytokeratin‐containing cells (e.g., in synovial endothelium) and could be a useful disease marker in RA.