bluuebunny/crossref_metadata_2025 huggingface dataset:
Oxycodone/acetaminophen at low dosage: An alternative pain treatment for patients with rheumatoid arthritis
Authors: Raffaeli, MD William , Pari, MD Claudia , Corvetta, MD Angelo , Sarti, PhD Donatella , Di Sabatino, MD Valentina , Biasi, MD Giovanni , Galeazzi, MD Maurizio
Published: July 2011

Objectives: To assess efficacy and safety of the association oxycodone/acetaminophen (oxycodone/ acetaminophen) for pain treatment and disability improvement in patients with rheumatoid arthritis (RA).Methods: Patients with RA (n = 29), suffering from moderate to severe pain for more than 3 months, were included in the study, except those under RA therapy with biological drugs. The treatment started with oxycodone/acetaminophen at the dosage of 5 mg/325 mg, and then the dosage was titrated until the attainment of good pain relief. Antiemetic and laxative therapy was used for the prophylaxis of known opioid-related adverse events.Results: Patients continued their RA therapy without changing the dosages, reported reduced pain intensity and disease activity, and improvement of disability. Forty-two percent of patients had a good clinical response to oxycodone/acetaminophen treatment, according to European League against Rheumatism (EULAR) assessment criteria, and 50 percent of patients reached the American College of Rheumatology 20 percent improvement criteria (ACR20). At the end of the study, the mean (±SD) daily effective oxycodone/acetaminophen dose was 13.8 (±6.8) mg/720.4 (±291.0) mg. No serious adverse event was observed. Nausea, vomiting, and stipsis of mild-moderate intensity were the most common adverse events.Conclusion: Oxycodone/acetaminophen at low dosages for the treatment of chronic pain in RA patients can be a good alternative to non-steroidal anti-inflammatory drugs (NSAIDs), allowing the reduction of their consumption, while keeping RA therapy stable.
Teaching clinical opioid pharmacology with the Human Patient Simulator
Authors: Hassan, MD Zaki , DiLorenzo, MA Amy , Sloan, MD Paul
Published: July 2011

Objective: Postoperative pain should be aggressively treated to decrease the development of chronic postsurgical pain. There has been an increase in the use of Human Patient Simulator (HPS) for teaching advanced courses in pharmacology to medical students, residents, and nurses. The aim of this educational investigation was to pilot the HPS for the training of medical students and surgical recovery room staff nurses in the pharmacology of opioids for the management of postoperative pain.Methods: The computerized HPS mannequin is fully monitored with appropriate displays and includes a voice speaker mounted in the head. Medical students and Postanesthesia care unit nurses, led by faculty in the Department of Anesthesiology in small groups of 4-6, participated in a 2- to 3-hour HPS course on the use of opioids for the management of acute postoperative pain. Trainees were asked to treat the acute and severe postoperative pain of a simulated patient. Opioid effects and side effects (such as respiratory depression) were presented on the mannequin in real time to the participants. Side effects of naloxone to reverse opioid depression were presented as a crisis in real time to the participants. Participants completed a 10-item course evaluation using a 5-point Likert scale (1 = strongly disagree; 5 = strongly agree).Results: Twenty-two nurses and nine medical students completed the HPS opioid pharmacology scenario. Almost all participants rated the HPS course very highly and rated every item as either agree or strongly agree. Most participants agreed that the simulator session improved their understanding of opioid pharmacology including opioid side effects and management of opioid complications. Course participants felt most strongly (median, interquartile range) that the simulator session improved their understanding of naloxone pharmacology (5, 0), simulators serve as a useful teaching tool (5, 0), and that they would be pleased to participate in any additional HPS teaching sessions (5, 0).Conclusions: The HPS provides a novel educational format to teach essential information regarding opioid pharmacology for the management of acute postoperative pain. The HPS provides a realistic format to teach the pharmacology of acute opioid side effects and the management of acute and life-threatening side effects of naloxone therapy.
Observations of medication compliance by measurement of urinary drug concentrations in a pain management population
Authors: West, MS Robert , Pesce, PhD, DABCC Amadeo , West, PhD Cameron , Crews, PhD Bridgit , Mikel, PhD Charles , Rosenthal, DO, FAPA Murray , Almazan, CLS, MT (ASCP) Perla , Latyshev, MS Sergey
Published: July 2011

Background: One of the major concerns of physicians treating pain patients with opioids is to determine whether the patients are compliant, and this is commonly determined by urine drug testing. There is limited information on which drugs these patients are most compliant with. There is also limited information as to how compliance is defined in terms of cutoffs.Objective: To compare reported patient medication use with the presence of the drug in the patients’ urine with defined cutoffs.Method: A retrospective study of the medications listed by the physicians’ offices and the confirmed drug test findings. A Millennium Laboratories database of 20,457 patient results was examined for the presence of the listed medications and was matched for the presence of the drugs above the analytical cutoffs.Results: For oxycodone and hydrocodone, the authors observed 23 and 24 percent noncompliance, respectively. For carisoprodol, they observed 33 percent noncompliance. For morphine, they observed 14 percent noncompliance. For methadone, they observed 9 percent noncompliance.Conclusions: Noncompliance is prevalent in this patient population and varies with the prescribed drug.
Rationales behind the choice of administration form with fentanyl: Delphi survey among Danish general practitioners
Authors: Jacobsen, PhD Ramune , Møldrup, PhD Claus , Christrup, PhD Lona
Published: July 2011

Background and Aim: The aim of this study was to describe the rationale behind the choice of fentanyl administration forms among Danish general practitioners (GPs).Methods: Thirty-eight Danish GPs were contacted via an Internet survey system to perform a Delphi survey. In the brainstorming phase, the main reasons for prescribing and not prescribing fentanyl patches, oral transmucosal systems (OTFCs), and nasal sprays were identified. In the second phase, GPs were asked to rate the importance of each reason.Results and Discussion: Thirty-three GPs responded in the brainstorming phase, and 33 and 31 in two rating rounds, respectively. The most important reason to choose fentanyl patches was that patients’ clinical condition did not allow them to take analgesia orally. OTFCs were primarily seen as a self-administrative alternative to injections in case of breakthrough pain. The main reasons for not choosing OTFCs were intolerance to fentanyl and price. The most important possible rationale to choose fentanyl nasal spray was easy administration. The most important possible reasons to not choose fenanyl nasal spray were application side effects.Conclusions: The rationale behind the choice of administration form with fentanyl partly differed from those overviewed in the literature. Fentanyl nasal spray was seen as a better option for treatment of breakthrough pain among terminally ill patients if compared with OTFCs.
The Eastern North Carolina Opioid Prescribers Project: A model continuing medical education workshop
Authors: Crozier, EdD Mary K. , McMillan, PhD Student Sherrá , Hudson, PhD Suzanne , Jones, MS Stephanie
Published: July 2011

The decision to prescribe opioid medications is complex. Physicians often struggle to balance the risks of medication diversion and abuse with the benefits of pain management. Nationally, more than 40 percent of primary care physicians report difficulty in discussing the possibility of prescription medication abuse with patients and more than 90 percent fail to detect symptoms of substance abuse. Continuing medical education workshops were developed in Eastern North Carolina to mitigate problems with opioid prescriptions. Attendance at these workshops suggests that prescribers are interested in improving opioid prescribing practices and reducing patient risk. Presurvey data indicate that prescribers are knowledgeable about screening tools and they consider patient risk factors for misuse.
Patient selection and trialing techniques utilizing low-dose intrathecal morphine for chronic nonmalignant pain: A report of two cases
Authors: Grider, DO, PhD Jay S. , Harned, MD Michael E. , Sloan, MD Paul A.
Published: July 2011

The administration of opioid analgesics via the intrathecal route is becoming more commonplace for a variety of chronic nonmalignant pathologic pain states. Despite this growing trend, there is very little information available to guide practitioners with regard to patient selection as well as intrathecal drug dosing paradigms. The authors describe the use of a protocol for patient selection, including pretrial preparation, as well as detailed very low-dose chronic intrathecal morphine dosing regimens to treat patients with refractory chronic nonmalignant pain.
Defining clinical issues around tolerance, hyperalgesia, and addiction: A quantitative and qualitative outcome study of long-term opioid dosing in a chronic pain practice
Authors: Schneider, MD, PhD Jennifer P. , Kirsh, PhD Kenneth L.
Published: July 2011

Treatment with opioid medications has grown over the past decades, but has been surrounded by some ongoing controversy and debate to whether it is causing more harm than good for patients. To this end, the field of pain management has suffered from a lack of clarity about some basic definitions on concepts such as tolerance and hyperalgesia. Some characterize these issues as inevitable parts of opioid therapy while other schools of thought look at these issues as relatively rare occurrences. Unfortunately, most of the rhetoric around these topics has occurred with very little in the realm of real world data. To this end, the authors have reviewed the charts of 197 patients treated by a pain specialist for at least 1 year to better illustrate whether notions of tolerance and hyperalgesia are common occurrences and, more importantly, whether they occur within any type of specified timeframe. A total of 197 patient charts were reviewed. The sample had an average age of 49.39 years (range = 19-87 years; standard deviation [SD] = 12.48) and comprised 66 men (33.5 percent) and 131 women (66.5 percent). The patients were seen in the pain practice for an average of 56.52 months (range = 12-155 months; SD = 31.26). On average, the patients maintained an average daily dose of 180 mg morphine equivalents for a period of 35.1 months (range = 3-101 months; SD = 21.3). Looking at the pattern of medication usage change over time, 34.5 percent experienced dose stabilization after the initial titration, 13.2 percent had early dose stabilization within one dose change, and an additional 14.7 percent actually had dose decreases after surgeries or other interventional procedures. Only 6.6 percent of the sample had to be discharged or weaned from controlled substances over time in the clinic. Thus, it appears that tolerance and hyperalgesia are not foregone conclusions when considering placing a patient on long-term opioid therapy.
Neonatal abstinence scores in opioid-exposed and nonexposed neonates: A blinded comparison
Authors: Jones, PhD Hendrée E. , Harrow, RN-LRN, MS, FNP-BC, IBCLC Cheryl , O’Grady, PhD Kevin E. , Crocetti, MD Michael , Jansson, MD Lauren M. , Kaltenbach, PhD Karol
Published: July 2011

Twenty-nine opioid-exposed and 26 nonopioid-exposed neonates received neonatal abstinence syndrome (NAS) assessment by an examiner blinded to group status twice daily over the first two postnatal days. The opioid-exposed group had higher mean NAS scores than the nonopioid-exposed group. A 3-sign index, consisting of hyperactive moro reflex, mild tremors when undisturbed, and increased muscle tone, showed excellent discrimination between groups. The use of a 3-sign screening index in the days immediately after birth may provide a cost-effective mechanism for the identification of opioid-exposed infants, particularly in infants of women for whom identification of status as a substance user may not be immediately evident. Although a potentially useful screening tool, the 3-sign screening tool should not replace the full assessment of the opioid-exposed infant after birth.
Improved detection of ethyl glucuronide and ethyl sulfate in a pain management population using high-throughput LC-MS/MS
Authors: Crews, PhD Bridgit , Latyshev, MS Sergey , Mikel, PhD Charles , Almazan, CLS, MT (ASCP) Perla , West, MS Robert , Pesce, PhD, DABCC Amadeo , West, PhD Cameron
Published: July 2011

Background: Ethyl glucuronide (EtG) and ethyl sulfate (EtS) have been proposed as markers for detecting alcohol use because they exhibit extended excretion lifetimes when compared with ethanol; however, their presence is not considered as absolute proof of alcohol use. Two methods are currently used for the detection and quantitation of EtG: immunoassay and mass spectrometry. The purpose of this study was to provide more patient data to better compare the two methods.Methods: A retrospective diagnostic accuracy study was performed to compare the methods. EtS was also measured by liquid chromatography-tandem mass spectrometry (LC-MS/MS) as an additional comparative analyte. The investigators examined 4,287 sequential urines from pain patients to determine the incidence of alcohol use and the corresponding presence of EtG by immunoassay at a cutoff of 500 ng/mL. EtG and EtS were subsequently quantitated in all the urines using LC-MS/MS.Results: A total of 794 samples were found positive by immunoassay, and these results were compared at three distinct LC-MS/MS cutoffs of 100, 500, and 1,000 ng/mL. The incidence of ethanol use in this population was found to be at least 12 percent.Conclusions: Approximately 30 percent of the samples screened by immunoassay as positive were confirmed to be negative by LC-MS/MS.
Current concepts in the management of opioid-induced constipation: A perfect review with an imperfect concept
Authors: Ruan, MD Xiulu , Montagnini, MD, FACP Marcos , Walters, MD Brandon JB
Published: July 2011

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Aerosol modelling in Europe with a focus on Switzerland during summer and winter episodes
Authors: Aksoyoglu S. , Keller J. , Barmpadimos I. , Oderbolz D. , Lanz V. A. , Prévôt A. S. H. , Baltensperger U.
Published: July 2011

Abstract. This paper describes aerosol modelling in Europe with a focus on Switzerland during summer and winter periods. We modelled PM2.5 (particles smaller than 2.5 μm in aerodynamic diameter) for one summer and two winter periods in years 2006 and 2007 using the CAMx air quality model. The meteorological fields were obtained from MM5 simulations. The modelled wind speeds during some low-wind periods, however, had to be calibrated with measurements to use realistic input for the air quality model. The detailed AMS (aerosol mass spectrometer) measurements at specific locations were used to evaluate the model results. In addition to the base case simulations, we carried out sensitivity tests with modified aerosol precursor emissions, air temperature and deposition. Aerosol concentrations in winter 2006 were twice as high as those in winter 2007, however, the chemical compositions were similar. CAMx could reproduce the relative composition of aerosols very well both in the winter and summer periods. Absolute concentrations of aerosol species were underestimated by about 20 %. Both measurements and model results suggest that organic aerosol (30–38 %) and particulate nitrate (30–36 %) are the main aerosol components in winter. In summer, organic aerosol dominates the aerosol composition (55–57 %) and is mainly of secondary origin. The contribution of biogenic volatile organic compound (BVOC) emissions to the formation of secondary organic aerosol (SOA) was predicted to be very large (>95 %) in Switzerland. The main contributors to the modelled SOA concentrations were oxidation products of monoterpenes and sesquiterpenes as well as oligomerization of oxidized compounds. The fraction of primary organic aerosol (POA) derived from measurements was lower than the model predictions indicating the importance of volatility of POA, which has not yet been taken into account in CAMx. Sensitivity tests with reduced NOx and NH3 emissions suggest that aerosol formation is more sensitive to ammonia emissions in winter in a large part of Europe. In Switzerland however, aerosol formation is predicted to be NOx-sensitive. In summer, effects of NOx and NH3 emission reductions on aerosol concentrations are predicted to be lower mostly due to lower ammonium nitrate concentrations. In general, the sensitivity to NH3 emissions is weaker in summer due to higher NH3 emissions.
Analysis of coherent structures and atmosphere-canopy coupling strength during the CABINEX field campaign: implications for atmospheric chemistry
Authors: Steiner A. L. , Pressley S. N. , Botros A. , Jones E. , Chung S. H. , Edburg S. L.
Published: July 2011

Abstract. Intermittent coherent structures can be responsible for a large fraction of the chemical exchange between the vegetation canopy and the atmosphere. Quantifying their contribution to fluxes is necessary to interpret measurements of trace gases and aerosols within and above forest canopies. The primary objective of the Community Atmosphere-Biosphere Interactions Experiment (CABINEX) field campaign (10 July 2009 to 9 August 2009) was to study the chemistry of volatile organic compounds (VOC) within and above a forest canopy. In this manuscript, we provide an analysis of coherent structures and canopy-atmosphere exchange during CABINEX to support in-canopy gradient measurements of VOC. We quantify the number and duration of coherent structure events and their percent contribution to momentum and heat fluxes with two methods: (1) quadrant-hole analysis and (2) wavelet analysis. Despite differences in the duration and number of events, both methods predict that coherent structures contribute 40–50 % to total momentum fluxes and 44–65 % to total heat fluxes during the CABINEX campaign. Contributions associated with coherent structures are slightly greater under stable rather than unstable conditions. By comparing heat fluxes within and above the canopy, we determine the degree of coupling between upper canopy and atmosphere and find that they are coupled to the majority of the campaign time period. Uncoupled canopy-atmosphere events occur in the early morning (04:00–08:00 LT) approximately 30 % of the time. This study confirms that coherent structures contribute significantly to the exchange of heat and momentum between the canopy and atmosphere at the CABINEX site, and indicates the need to include these transport processes when studying the mixing and chemical reactions of trace gases and aerosols between a forest canopy and the atmosphere.
Operational total and tropospheric NO2 column retrieval for GOME-2
Authors: Valks P. , Pinardi G. , Richter A. , Lambert J.-C. , Hao N. , Loyola D. , Van Roozendael M. , Emmadi S.
Published: July 2011

Abstract. This paper presents the algorithm for the operational near real time retrieval of total and tropospheric NO2 columns from the Global Ozone Monitoring Experiment (GOME-2). The retrieval is performed with the GOME Data Processor (GDP) version 4.4 as used by the EUMETSAT Satellite Application Facility on Ozone and Atmospheric Chemistry Monitoring (O3M-SAF). The differential optical absorption spectroscopy (DOAS) method is used to determine NO2 slant columns from GOME-2 (ir)radiance data in the 425–450 nm range. Initial total NO2 columns are computed using stratospheric air mass factors, and GOME-2 derived cloud properties are used to calculate the air mass factors for scenarios in the presence of clouds. To obtain the stratospheric NO2 component, a spatial filtering approach is used, which is shown to be an improvement on the Pacific reference sector method. Tropospheric air mass factors are computed using monthly averaged NO2 profiles from the MOZART-2 chemistry transport model. An error analysis shows that the random error in the GOME-2 NO2 slant columns is approximately 0.45 × 1015 molec cm−2. As a result of the improved quartz diffuser plate used in the GOME-2 instrument, the systematic error in the slant columns is strongly reduced compared to GOME/ERS-2. The estimated uncertainty in the GOME-2 tropospheric NO2 column for polluted conditions ranges from 40 to 80 %. An end-to-end ground-based validation approach for the GOME-2 NO2 columns is illustrated based on multi-axis MAXDOAS measurements at the Observatoire de Haute Provence (OHP). The GOME-2 stratospheric NO2 columns are found to be in good overall agreement with coincident ground-based measurements at OHP. A time series of the MAXDOAS and the GOME-2 tropospheric NO2 columns shows that pollution episodes at OHP are well captured by GOME-2. Monthly mean tropospheric columns are in very good agreement, with differences generally within 0.5 × 1015 molec cm−2.
Corrigendum to "Measuring the 3-D wind vector with a weight-shift microlight aircraft" published in Atmos. Meas. Tech., 4, 1421–1444, 2011
Authors: Metzger S. , Junkermann W. , Butterbach-Bahl K. , Schmid H. P. , Foken T.
Published: July 2011

Abstract. This study investigates whether the 3-D wind vector can be measured reliably from a highly transportable and low-cost weight-shift microlight aircraft. We draw up a transferable procedure to accommodate flow distortion originating from the aircraft body and -wing. This procedure consists of the analysis of aircraft dynamics and seven successive calibration steps. For our aircraft the horizontal wind components receive their greatest single amendment (14 %, relative to the initial uncertainty) from the correction of flow distortion magnitude in the dynamic pressure computation. Conversely the vertical wind component is most of all improved (31 %) by subsequent steps considering the 3-D flow distortion distribution in the flow angle computations. Therein the influences of the aircraft's trim (53 %), as well as changes in the aircraft lift (16 %) are considered by using the measured lift coefficient as explanatory variable. Three independent lines of analysis are used to evaluate the quality of the wind measurement: (a) A wind tunnel study in combination with the propagation of sensor uncertainties defines the systems input uncertainty to ≈0.6 m s−1 at the extremes of a 95 % confidence interval. (b) During severe vertical flight manoeuvres the deviation range of the vertical wind component does not exceed 0.3 m s−1. (c) The comparison with ground based wind measurements yields an overall operational uncertainty (root mean square error) of ≈0.4 m s−1 for the horizontal and ≈0.3 m s−1 for the vertical wind components. No conclusive dependence of the uncertainty on the wind magnitude (<8 m s−1) or true airspeed (ranging from 23–30 m s−1) is found. Hence our analysis provides the necessary basis to study the wind measurement precision and spectral quality, which is prerequisite for reliable Eddy-Covariance flux measurements.
Transportation Policy: Precedent-Breaking Choices over Five Decades
Authors: Spychalski John C
Published: July 2011

Dramatic changes in transport policy have occurred since publication of the inaugural issue of Transportation Journal. Paramount among these changes is economic deregulation. It brought to a vestige the once-comprehensive structure of control over business behavior in transport markets that had endured since its 19th-century starting point. As economic regulation receded, environmental, safety, and security regulation of transport burgeoned, driven more strongly by political than by economic calculations. Determination of whether its benefits exceed its costs will require a longterm horizon rather than a short-run one. Emerging political currents portend contraction of both publicly funded transport services, and infrastructure quality and capacity. Looking ahead, crafting and implementation of means for adequate funding—and for economically rational safety, security, and environmental standards—stand as prime transport policy challenges between the Golden and Diamond Anniversaries of the Transportation Journal.
Historical Perspective of the Logistics and Supply Chain Management Discipline
Authors: Southern R. Neil
Published: July 2011

The purpose of this article is to examine the evolution of the study of business logistics and supply chain management from the perspective of one who has participated firsthand in the discipline in industry and academic positions over the past six decades. The subject matter is organized in chronological order by decade. The 1950s were primarily a decade of transportation. During the 1960s the study of transportation evolved into the study of physical distribution. During the early 1970s more attention was given to physical supply, the inbound side of logistics systems. Later in the 1970s, universities began to offer more courses in transportation, physical distribution, and logistics. The term physical distribution was phased out in the 1980s, and the term business logistics emphasized. During the 1990s, business logistics again was the emphasis, as many cost-oriented businesses became aware of the opportunities for cost savings through negotiations with carriers and implementation of the systems approach and the total cost concept. The first decade of the 21st century has been characterized by a slow evolution from logistics to supply chain management.
Fine-Needle Aspiration Cytology Is an Alternative Source of High Quality Archival Samples in Biobanking
Authors: Malami Sani Abubakar
Published: July 2011

Advances in fine-needle aspiration cytology (FNAC) techniques allows for a whole range of procedures on these limited sources of tissue. Where fresh aspirates are not readily available, archival FNAC samples had also been used for clinical diagnoses, molecular profiling, and disease monitoring with impressive results. Nonetheless, legitimate concerns exist regarding the reliability of these banked specimens. Increased demands on human tissues in response to the rapid acceleration on emerging scientific platforms will probably make tissue bank creation derived from archival FNAC a priority. To highlight its future prospects as a resource for tissue banking, this paper provides an overview of the use of archival FNAC in clinical situations and ancillary studies. It is concluded that tissue banks of archival FNAC specimens might have great promise in optimizing patient care and translational research.
A Deterministic Inventory Model of Deteriorating Items with Two Rates of Production, Shortages, and Variable Production Cycle
Authors: Bhowmick Jhuma , Samanta G. P.
Published: July 2011

A Continuous production control inventory model is developed for a deteriorating item having shortages and variable production cycle. It is assumed that the production rate is changed to another at a time when the inventory level reaches a prefixed level and continued until the inventory level reaches the level . The demand rate is assumed to be constant, and the production cycle T is taken as variable. The production is started again at a time when the shortage level reaches a prefixed quantity . For this model, the total cost per unit time as a function of , , S, and T is derived. The optimal decision rules for , , S, and T are computed. The sensitivity of the optimal solution towards changes in the values of different system parameters is also studied. Results are illustrated by numerical examples.
Long Form and Algorithm
Authors: Bosia Daniel
Published: July 2011

Computer algorithms and scripting provide engineers and architects with the opportunities to design in a nonlinear way. This is a matter of learning from nature's evolutionary and nonlinear processes rather than mimicking them. Daniel Bosia describes how Arup's Advanced Geometry Group (AGU) has developed a method that uses abstract genetic algorithms to create rational and systematic organisations of space, which are structured and rational to construct and assemble. Copyright © 2011 John Wiley & Sons, Ltd.
One‐Step Fabrication of Multifunctional Core‐Shell Fibres by Co‐Electrospinning
Authors: Medina‐Castillo Antonio L. , Fernández‐Sánchez Jorge F. , Fernández‐Gutiérrez Alberto
Published: July 2011

In the present study, multifunctional core‐shell fibre mats were designed by co‐electrospinning. These core‐shell fibre mats have three different functionalities: 1) they are magnetic, 2) they change their optical properties with the pH of the media, and 3) they are sensitive to O2. The shell is formed by a fluorescent pH‐sensitive co‐polymer which was previously synthesised and characterized by our research group. The core is a suspension formed by magnetic nanoparticles in a solution made up by a lipophilic indicator dye (oxygen indicator; PtOEP) and, poly‐methyl methacrylate, in THF. The magnetic nanoparticles were prepared by encapsulation of magnetite within a cross‐linked polymeric matrix (MMA‐co‐EDMA). To our knowledge, this is the first time that three functionalities (magnetic properties, sensitivity to pH, and response to O2 concentration) were successful conjugated on the same micro‐ or nano‐material via a facile one‐step process with high yield and cost effectiveness.

The morphology of the well‐organized core‐shell fibres were characterized by high resolution scanning electron microcopy (HRSEM), transmission electron microcopy (TEM), and confocal laser microscopy. The luminescent properties of core‐shell fibre mats were analysed and successfully used for simultaneously monitoring pH (from 6 to 8) and O2, showing complete reversibility, high sensitivity (i.e., Ksv = 7.07 bar−1 for determining O2 in aqueous media), high magnetic susceptibility, and short response times.
Facile Physical Route to Highly Crystalline Graphene
Authors: Jin Meihua , Kim Tae Hyung , Lim Seong Chu , Duong Dinh Loc , Shin Hyeon Jin , Jo Young Woo , Jeong Hae Kyung , Chang Jian , Xie Sishen , Lee Young Hee
Published: July 2011

A physical route is proposed to obtain highly crystalline graphene sheets with minimal oxygen content similar to the precursor graphite. The functional graphene sheets obtained from graphite oxide by low temperature thermal exfoliation are annealed at high temperature (1900 °C) in a vacuum (10−6 torr). The D band intensity in Raman spectroscopy is reduced significantly, while the G band intensity is recovered, similar to the level of precursor graphite. No appreciable oxygen content is observed from X‐ray photoelectron spectroscopy and an electrical conductivity of ∼56 500 S m−1 is obtained, comparable to 100 900 S m−1 of the precursor graphite.
New Silicone Composites for Dielectric Elastomer Actuator Applications In Competition with Acrylic Foil
Authors: Opris Dorina M. , Molberg Martin , Walder Christian , Ko Yee Song , Fischer Beatrice , Nüesch Frank A.
Published: July 2011

Several polydimethylsiloxane elastomers were developed and investigated regarding their potential use as materials in dielectric elastomer actuators (DEA). A hydroxyl end‐functionalized polydimethylsiloxane was reacted with different crosslinkers and the electromechanical properties of the resulting elastomers were investigated. The silicone showing the best actuation at the lowest electric field was further used as matrix and compounded with encapsulated conductive polyaniline particles. These composites have enhanced properties including increased strain at break, higher dielectric constant as well as, gratifyingly, breakdown fields higher than that of the matrix. One of the newly synthesized composites is compared to the commercially available acrylic foil VHB 4905 (3M) which is currently the most commonly used elastomer for DEA applications. It was found that this material has little hysteresis and can be activated at lower voltages compared to VHB 4905. For example, when the newly synthesized composite was 30% prestrained, a lateral actuation strain of about 12% at 40 V μm−1 was measured while half of this actuation strain at the same voltage was measured for VHB 4905 film that was 300% prestrained. It also survived more than 100 000 cycles at voltages which are close to the breakdown field. Such materials might find applications wherever small forces but large strains at low voltages are required, in, for example, tactile displays.
Hierarchical Self‐assembly of Microscale Cog‐like Superstructures for Enhanced Performance in Lithium‐Ion Batteries
Authors: Zhang Weixin , Li Mei , Wang Qiang , Chen Gongde , Kong Mei , Yang Zeheng , Mann Stephen
Published: July 2011

Assembling complex nanostructures on functional substrates such as electrodes promises new multi‐functional interfaces with synergetic properties capable of integration into larger‐scale devices. Here, we report a microemulsion‐mediated process for the preparation of CuO/Cu electrodes comprising a surface layer of a densely packed array of unusual cog‐shaped CuO microparticles with hierarchical nanofilament‐based superstructure and enhanced electrochemical performance in lithium‐ion batteries. The CuO particles are produced by thermolysis of Cu(OH)2 micro‐cog precursors that spontaneously assemble on the copper substrate when the metal foil is treated with a reactive oil‐based microemulsion containing nanometer‐scale aqueous droplets. The formation of the hierarchical superstructure improves the coulombic efficiency, specific capacity, and cycling performance compared with anodes based on CuO nanorods or polymer‐blended commercial CuO/C black powders, and the values for the initial discharge capacity (1052 mA h g−1) and reversible capacity (810 m A h g−1) are higher than most copper oxide materials used in lithium‐ion batteries. The results indicate that a fabrication strategy based on self‐assembly within confined reaction media, rather than direct synthesis in bulk solution, offers a new approach to the design of electrode surface structures for potential development in a wide range of materials applications.
Oxygen permeation through a CO2‐tolerant mixed conducting oxide (Pr0.9La0.1)2(Ni0.74Cu0.21Ga0.05)O4+δ
Authors: Tang Jun , Wei Yanying , Zhou Lingyi , Li Zhong , Wang Haihui
Published: July 2011

A novel K2NiF4‐type oxide based on (Pr0.9La0.1)2(Ni0.74Cu0.21Ga0.05)O4+δ (PLNCG) dense mixed conducting ceramic membrane was successfully prepared through a sol–gel route. The oxygen permeation flux through the membrane swept by pure CO2 was comparative to that swept by He. The oxygen permeation and the stability of PLNCG under pure CO2 were investigated in detail. A membrane with a thickness of 0.8 mm was steadily operated for 230 h with a constant oxygen permeation flux of 0.32 mL/(min cm2) at 975°C using pure CO2 as sweep gas. X‐ray diffraction shows that PLNCG can maintain its fluorite phase, and no carbonates were observed, even when it was exposed to pure CO2 for a long time. © 2011 American Institute of Chemical Engineers AIChE J, 58: 2473–2478, 2012
Cyclobutanes in Catalysis
Authors: Seiser Tobias , Saget Tanguy , Tran Duc N. , Cramer Nicolai
Published: July 2011

The exploitation of ring strain as a driving force to facilitate chemical reactions is a well‐appreciated principle in organic chemistry. The most prominent and most frequently used compound classes in this respect are oxiranes and cyclopropanes. For rather a long time, cyclobutanes lagged behind these three‐membered‐ring compounds in their development as reactive substrates, but during the past decade an increasing number of useful reactions of four‐membered‐ring substrates have emerged. This Minireview examines corresponding catalytic reactions ranging from Lewis or Brønsted acid catalyzed processes to enzymatic reactions. The main focus is placed on transition‐metal‐catalyzed CC bond‐insertion and β‐carbon‐elimination processes, which enable exciting downstream reactions that deliver versatile building blocks.
Novel dielectric behaviors in PVDF‐based semiconductor composites
Authors: Xu Hai‐Ping , Xie Hua‐Qing , Yang Dan‐Dan , Wu Yi‐Hua , Wang Jing‐Rong
Published: July 2011

Composites of polyvinylidene fluoride (PVDF) filled with different conductive fillers as carbon black (CB), nickel (Ni), zinc (Zn), and tungsten (W), respectively, were prepared at same processing condition. The temperature dependence of dielectric behaviors of composites was studied at wide filler concentration and wide frequency ranges. Results show that there are giant dielectric constants as the concentration of filler is near the percolation threshold. The dielectric constants of all studied composites decrease slowly with increasing of frequency and rise gradually with increasing filler contents in the composites. Two relaxation peak regions of dielectric constant are observed from −30 to 40°C and from 100 to 150°C, which can be attributed to the contribution of polar effect of PVDF. The CB filled PVDF (CB/PVDF) composites present a lower percolation threshold than other metallic‐filler filled PVDF composites. The maximal dielectric constant was found in the Ni filled PVDF (Ni/PVDF) composite. © 2011 Wiley Periodicals, Inc. J Appl Polym Sci, 2011
Swelling behavior and structural characteristics of polyvinyl alcohol/montmorillonite nanocomposite hydrogels
Authors: Sirousazar M. , Kokabi M. , Hassan Z. M.
Published: July 2011

A series of nanocomposite hydrogels based on polyvinyl alcohol containing 0–10 wt % of the organically modified montmorillonite clay were prepared by freezing‐thawing cyclic method. The morphology of the nanocomposite hydrogels was observed by the scanning electron microscopy technique. The structural properties were determined by measuring the network mesh size, crosslinking density, and average molecular weight of polymer chains between crosslinks. The swelling behavior and the effect of swelling medium temperature on the swelling kinetics and characteristics of the nanocomposite hydrogels were also investigated. The results showed that two structural characteristics i.e., network mesh size and average molecular weight of polymer chains between crosslinks have inverse dependence on the clay loading level in the nanocomposite hydrogel, while crosslinking density shows completely direct dependence. Swelling measurements demonstrated a linear relation between the degree of swelling and the square root of immersion time at all swelling medium temperatures. The results indicated that the swelling characteristics of the nanocomposite hydrogels including the equilibrium degree of weight and volume swelling and the equilibrium water content were decreased by increasing the quantity of the clay incorporated into the hydrogel as well as by decreasing the temperature of swelling medium. While, the time required to reach to the equilibrium condition, as another swelling characteristic of the hydrogels, exhibited a completely opposite behavior. © 2011 Wiley Periodicals, Inc. J Appl Polym Sci, 2011.
Relationship between thermal properties, morphology, and crystallinity of nanocomposites based on polyhydroxybutyrate
Authors: D'Amico David A. , Manfredi Liliana B. , Cyras Viviana P.
Published: July 2011

Polyhydroxybutyrate (PHB) has a significant instability at temperature close to the melting point. The aim of this work was to improve the thermal resistance of PHB by the addition of small amounts of two different types of clays: Cloisite® Na+ (CNa+) and Cloisite® 15A (C15A). C15A has more hydrophobic character and interlayer distance than CNa+. It was observed that the addition of the organically modified montmorillonite (MMT) increased by more than 15°C the thermal resistance of the PHB while the addition of CNa+ reduced it. This result was related to the different morphology of the final materials. The maximum in the degradation temperature of the nanocomposites with 4% of clay was in accordance with the maximum in the percentage of crystallinity. However, the interlayer gallery distance of the C15A was higher than the CNa+ in the PHB matrix, according to the better thermal stability of the C15A due to the higher barrier effect and the lower chain mobility. A slight increase in the Young modulus of the polymer was observed with the addition of C15A, due to the compatibility between the MMT and PHB. The calorimetric and microscopy results showed that clays did not accelerate the formation of PHB spherulites nucleus, but the lamellar velocity was accelerated. © 2011 Wiley Periodicals, Inc. J Appl Polym Sci, 2011
Effect of glycerol on thermal and mechanical properties of polyvinyl alcohol/starch blends
Authors: Sreekumar P. A. , Al‐Harthi Mamdouh A. , De S. K.
Published: July 2011

The paper reports the results of studies on the effect of glycerol content on thermal, mechanical, and dynamic mechanical properties of blends of starch and polyvinyl alcohol (PVA). Degree of crystallinity of the starch/PVA blends (4 g/4 g ratio) remains almost constant up to 3.78 g of glycerol as determined by differential scanning calorimetry (DSC) and x‐ray diffraction studies. At higher loading of glycerol the crystallinity decreases. DTG thermograms revealed occurring of one maximum degradation temperature closer to that of starch in blends containing up to 3.78 g of glycerol. At higher glycerol content there gradually occur two distinct peaks of maximum degradation temperature, one occurring close to that of starch and other occurring close to the PVA peak, indicating phase separation of the blend components. Results of stress–strain studies indicate lowering of tensile properties and energy at break particularly at higher glycerol content (beyond 3.78 g). Dynamic mechanical studies reveal a sharp drop in dynamic modulus at higher glycerol content at all temperatures. The blend with low glycerol content shows transitions of starch, while the blend containing high glycerol content beyond 3.78 g display the transitions due to both starch and PVA. © 2011 Wiley Periodicals, Inc. J Appl Polym Sci, 2011
A proposal to define vulnerability of cetacean areas to human development: variables and analysis procedures applied to the Gulf of California
Authors: Cubero‐Pardo Priscilla , Donovan Carl , Urbán‐Ramírez Jorge
Published: July 2011

Understanding spatial interactions between specific sources of anthropogenic impact on cetaceans and the ecological conditions intrinsic to these mammals, has several applications for conservation and management. Here cetacean habitats are classified into vulnerability levels by combining human development metrics and cetacean characteristics, allowing areas identified as more vulnerable to be given management priority.

Ten bio‐physical and anthropogenic factors were identified as key shapers of cetacean habitats and, using the Gulf of California as a case study, 18 variables were defined to measure those factors. Principal component analysis (PCA) and GIS were used to distill the relationships across all variables, in order to obtain a vulnerability index. Aggregates of variables were also investigated to map the spatial distribution of anthropogenic impacts and cetacean characteristics (species richness, relative abundance of encounter, residence condition, diet specificity and threat status). For this latter purpose, separate indices representing five ‘categories’ (pollution from land sources, urban development, potential for accidents, resource depletion and fragility of cetacean areas) and three ‘vulnerability components’ (risk of hazards, intrinsic resilience and damage) were calculated.

The methodology clearly differentiated the study area according to levels for each ‘category’ and ‘vulnerability component’, as well as to levels of vulnerability of cetacean areas in relation to human activities; and identified those variables with the greatest contributions, without recourse to the subjective criteria common in other approaches. The analyses were conducted using environmental units generated by the Marine Ecological Zoning Plan for the Gulf of California (OEMGC, by its Spanish acronym) which tied model outputs to this planning framework. The variables selected were easily obtainable through governmental and research institutions which make them suitable for adaptive management purposes.

Copyright © 2011 John Wiley & Sons, Ltd.
A weight‐of‐evidence approach to determine estuarine fish health using indicators from multiple levels of biological organization
Authors: Richardson N. , Gordon A. K. , Muller W. J. , Whitfield A. K.
Published: July 2011

A prototype Estuarine Fish Health Index (EFHI) using biological indicators from multiple levels of biological organization is described. Three test estuaries of similar size and morphology but with different development pressures were sampled for this purpose.

The EFHI integrates the well established Estuarine Fish Community Index (EFCI) developed for South African estuaries, which uses fish community level metrics to assess estuarine condition, with stress responses measured at lower levels of biological organization.

Four sub‐organism level biomarkers were used: liver histopathology assessment, acetylcholinesterase and lipid peroxidase assays and an individual fish condition factor analysis. The data from these analyses and the results of the EFCI were integrated to determine if combining these inputs produces a more sensitive and predictive tool for assessing estuarine health than when used in isolation.

Challenges and management applications of this new tool are explored and further studies to improve its prognostic capacity are suggested.

Copyright © 2011 John Wiley & Sons, Ltd.
Modelling spatial exclusion of a vulnerable native fish by introduced trout in rivers using landscape features: a new tool for conservation management
Authors: Woodford Darragh J. , Cochrane Thomas A. , McHugh Peter A. , McIntosh Angus R.
Published: July 2011

Habitat variability can affect the ability of invasive predators to exclude native prey species from parts of a landscape. If habitat consistently mediates predator impacts, the outcome of predator–prey interactions could be modelled using habitat data alone.

In New Zealand streams, invasive predatory trout create source–sink dynamics in populations of the native fish Galaxias vulgaris. Within trout‐invaded sink habitat, G. vulgaris are excluded from small, stable streams that occur far from galaxiid demographic sources (streams above barriers to trout).

A GIS‐based spatial model using stream size and distance‐to‐source data was developed to predict where trout would exclude G. vulgaris in a river network, and to detect undiscovered trout‐free source populations. The maximum distance from source streams at which G. vulgaris could co‐occur with trout was modelled in two trout‐invaded riverscapes using a quantile limit function in GIS. The predictive ability of the model was tested using training datasets and data from two independent catchments where fish occurrence patterns were quantified from electrofishing surveys.

The model correctly predicted G. vulgaris absence in the first test catchment, but failed to predict absence in the second test dataset because of an initial lack of knowledge of demographic sources and insufficient survey data. This demonstrated that G. vulgaris exclusion by trout could be predicted by the model, provided it is constructed and validated in an iterative fashion.

The current model provides a useful tool both for conserving critical source populations, as well as for selecting streams for rehabilitation through trout eradication. Since species interaction models based on landscape data are likely to be generally useful in guiding conservation management, researchers should investigate whether other biotic interactions that can be consistently predicted by habitat exist in nature.

Copyright © 2011 John Wiley & Sons, Ltd.