bluuebunny/crossref_metadata_2025 huggingface dataset:
Understanding why people do not give: strategic funding concerns for AIDS‐related nonprofits
Authors: Eveland Vicki Blakney , Crutchfield Tammy Neal
Published: December 2006

In this increasingly competitive environment for the individual donor's time and money, it is especially important for AIDS‐related nonprofits to understand why people choose not to give. Voluntary donations to organizations serving persons with HIV/AIDS could be negatively influenced by the social stigma that continues to be associated with the disease. Using the empathy‐altruism hypothesis from social psychology, the impact of gender, homosexuality, promiscuity, and drug use on donor cognitive situational empathy, emotional situational empathy, and altruism is examined. The findings have significant implications for nonprofits. Understanding the impact of these behaviors on giving is a first step in gauging the magnitude of challenges that AIDS‐related nonprofits may face in fund‐raising activities. Additionally, this information should be invaluable in the development of educational and/or promotional strategies to increase private sector support. Finally, initiatives in communication and marketing strategy are discussed to improve fund‐raising efforts.

Copyright © 2006 John Wiley & Sons, Ltd.
Multiple spinal epidural abscesses: a diagnostic challenge in a person with newly diagnosed diabetes and neck and back pain
Authors: Quah CSL , Bilous R
Published: December 2006

Epidural abscess is a rare medical emergency that requires a high index of suspicion in order to reach a timely diagnosis. It is more frequent in people with diabetes and, as the prevalence of type 2 diabetes is due to double over the next 20 years, physicians are likely to encounter it more often. We report a case of a man with newly presenting diabetes who attended the Accident & Emergency Department with severe hyperglycaemia and neck and back pain, and who was found to have multiple spinal abscesses. The diagnosis was not confirmed until six days after admission. This case highlights the need for increased awareness of the possibility of this serious condition. Copyright © 2006 John Wiley & Sons.
Oesophageal rupture secondary to gastric stasis, complicating severe diabetic ketoacidosis
Authors: Martin N , Ferrando L , Fletcher J , Leslie PJ
Published: December 2006

Gastric stasis is a common, and easily treated, complication of diabetic ketoacidosis (DKA). Here we report a case of oesophageal rupture in DKA that highlights the need for early nasogastric tube placement in patients with gastric stasis and protracted vomiting. Copyright © 2006 John Wiley & Sons.
Diabetic foot infections: an audit of antibiotic prescribing in a diabetic foot clinic
Authors: Wong M‐L , Coppini DV
Published: December 2006

Infected diabetic foot ulcers cause substantial morbidity and mortality. Antibiotic therapy is necessary for all infected ulcers but widespread antibiotic prescription can lead to adverse effects and increased resistance. The main purpose of this audit was to survey our antibiotic prescription pattern and to assess the appropriateness of prescriptions in the diabetic foot clinic.

We graded 85 consecutive wounds seen in the clinic using the University of Texas Wound Classification System (UTWCS). This system allows ulcers to be classified according to depth, presence of infection and ischaemia.

We found that 55 wounds (65%) were infected and antibiotics were prescribed for 51 wounds (93%). Four infected wounds did not have antibiotics prescribed. Four patients (7%) with infected ulcers required admission for intravenous antibiotic treatment. All four had deep infections involving bone. Deep wound swabs were performed on 52 of the infected wounds and three (6%) grew methicillin‐resistant Staphylococcus aureus. The antibiotics commonly used were cefradine, clindamycin, and combinations of clindamycin + ciprofloxacin or amoxicillin + flucloxacillin. In the remaining 30 uninfected wounds (35%), no antibiotics were prescribed.

In the foot clinic, antibiotic prescription was generally appropriate but not all patients with infected ulcers received antibiotic therapy. As a result of this audit, we have devised a simple antibiotic protocol in an attempt to improve the management of infected diabetic wounds in a safe, methodical and effective manner. Copyright © 2006 John Wiley & Sons.
Prevalence of obesity and unrecognised glucose intolerance in a UK day‐case surgery unit: observational study
Authors: Pratap JN , Clements E , Levy D
Published: December 2006

The objectives of this study were: to determine the prevalence of overweight and obesity in a day‐case surgery unit; to find out if obesity is more frequent than in the general population; and to assess glucose intolerance in obese day‐case unit attendees.

The study was conducted as a retrospective audit of prospectively collected observational data at a United Kingdom urban secondary care ambulatory surgery facility.

The study participants comprised 829 (99.0%) patients with complete anthropometric records out of 837 undergoing preoperative assessment between April 2004 and June 2004. The main outcome measures were: prevalence of overweight and obesity according to body mass index (BMI) stratification; and glycosylated haemoglobin A1c (HbA1c), random venous plasma glucose, and prevalence of unrecognised glucose intolerance in obese patients.

The results showed that 30.2% of 560 females had a BMI of 25–30kg/m2 (overweight), 19.1% 30–40kg/m2 (class 1 and 2 obesity), and 2.5% over 40kg/m2 (class 3 obesity); 45.0%, 14.9% and 0.7% of 269 males, respectively, were in these categories. The mean HbA1c of obese patients was significantly elevated at 6.33% (95% confidence interval 6.17–6.50%, p<0.001; non‐diabetic reference range 4.0–6.0%). In all, 11.4% of 70 obese females and 20.8% of 24 obese males for whom a result was available showed an HbA1c greater than 7.0% suggesting unrecognised diabetes.

The prevalence of obesity in the day‐case surgery unit is similar to that of the local population. Obese ambulatory surgery patients exhibit markedly abnormal glucose tolerance. The yield of targeted opportunistic screening for diabetes is particularly high in this group with a number needed to screen of five for men and nine for women in order to detect one case likely to need pharmacological intervention. Copyright © 2006 John Wiley & Sons.
Mechanical properties of layered silicate/starch polycaprolactone blend nanocomposites
Authors: Pérez C Javier , Alvarez Vera A , Mondragón Iñaki , Vázquez Analía
Published: December 2006

The mechanical behavior of layered silicate/starch polycaprolactone blend nanocomposites was evaluated. Three different clays (Cloisite Na+, Cloisite 30B and Cloisite 10A) were used as reinforcement. Nanocomposites were prepared by melt intercalation followed by compression molding. These nanocomposites were characterized using X‐ray diffraction, scanning electron microscopy, dynamic mechanical analysis and tensile testing. X‐ray diffraction results showed that most of the clays were intercalated within the polymeric chains. In all cases, mechanical properties were improved with clay incorporation and the improvement was better as the clay content was increased. The best properties were achieved with Cloisite 10A due to their greatest compatibility with the matrix. A mechanical model, which takes into account the effective parameters of the clay, was used in order to estimate the dispersion of clay within the polymer. The highest dispersion was obtained for Cloisite 10A, which is in accordance with the experimental mechanical properties. Although dynamical‐mechanical properties improved with clay incorporation, the glass transition temperature was not affected. Copyright © 2006 Society of Chemical Industry
Side‐chain functionalized supramolecular polymers
Authors: Weck Marcus
Published: December 2006

Over the past two decades, the field of supramolecular polymer chemistry has developed from a curiosity to a mature area of polymer science. Among the most promising subjects in this large field are noncovalently functionalized side‐chain polymers that have been investigated extensively as a result of their modular character and ease of synthesis. Side‐chain functionalized polymers have the potential for a profound impact on complex materials. For example, for side‐chain functionalized polymers based on a single noncovalent interaction, materials for a variety of applications ranging from liquid crystalline and electro‐optical materials to drug delivery systems have been reported. Furthermore, materials based on this novel methodology may overcome several shortcomings of current covalent multifunctionalization strategies such as highly complex materials that are extremely difficult or impossible to fabricate with current methods. In this review, basic design requirements, advantages and potential applications are presented. Copyright © 2006 Society of Chemical Industry
Outer membrane proteome of Prevotella intermedia 17: Identification of thioredoxin and iron‐repressible hemin uptake loci
Authors: Yu Fan , Anaya Cecilia , Lewis Janina P.
Published: December 2006

Although hemin is an indispensable nutrient for the oral pathogen Prevotella intermedia, not much is known regarding the molecular mechanisms of hemin acquisition. The availability of the genomic sequence of the bacterium allowed us to apply proteomic approaches to identify proteins that may be mediating the hemin acquisition process. As hemin acquisition mechanisms have been shown to be induced in iron‐depleted conditions, we applied proteomic approaches to detect those proteins whose expressions were affected by iron. We analyzed 40 protein spots and identified 19 such proteins. Interestingly, two proteins drastically upregulated in iron‐depleted conditions, PIN0009 and PINA0611, are homologs of hemin uptake receptors in other bacteria. PIN0009 is predicted to be an outer membrane lipoprotein. It is encoded by a gene that is the first of a seven‐gene genomic locus encoding proteins of a novel hemin acquisition system. The second protein, PINA0611, is a homolog of numerous TonB‐dependent outer membrane receptors including outer membrane iron uptake receptors of various Gram‐negative bacteria. There was also another protein, regulated by iron, that was previously demonstrated to bind hemoglobin in P. intermedia. Finally, we identified a thioredoxin‐like protein that has a novel outer membrane location.
Behaviors of the positive temperature coefficient of resistance of poly(styrene‐co‐n‐butylacrylate) filled with Ni‐plated core‐shell polymeric particles
Authors: Chang Jason , Ho Albert , Chin Wei‐Kuo
Published: December 2006

Conductive composite films of poly(styrene‐co‐n‐butylacrylate) copolymers filled with low‐density, Ni‐plated core‐shell polymeric particles were prepared and their behaviors of positive temperature coefficient of resistance (PTCR) were investigated. When the conductive fillers in the composite film were loaded beyond the critical volume, 10 up to 25 vol %, composite films exhibited a unique electrical resistant transition behavior, which the electrical resistance rapidly increased by several orders of magnitude at the critical temperature. The PTCR transition temperature, in general, occurred before the glass transition temperature of polymer matrix. Further increased the conductive filler loading to 30 vol %, the overpacked conduction paths were formed in the entire composite and the PTCR effects became blurred. While the composite film treated with thermal cycle several times from room temperature up to 120 °C, the electrical resistivity increased accompanied with the shift of the PTCR transition to lower temperature. The reason might have been caused by the formed interfacial cracks within the composite film. © 2006 Wiley Periodicals, Inc. J Polym Sci Part B: Polym Phys 45: 322–329, 2007
Preparation of a superhydrophobic rough surface
Authors: Lee Hoon Joo , Michielsen Stephen
Published: December 2006

The relationship between the contact angles, surface tension, and surface roughness is reviewed. Numerical formulas related to the superhydrophobic rough surfaces of polymers are predicted with two approaches, the Wenzel and Cassie–Baxter models. With these models as a guide, an artificial superhydrophobic surface is created. Rough nylon surfaces mimicking the lotus leaf are created by the coating of a polyester surface with nylon‐6,6 short fibers via the flocking process. Poly(acrylic acid) chains aregrafted onto nylon‐6,6 surfaces, and this is followed by the grafting of 1H,1H‐perfluorooctylamine onto the poly(acrylic acid) chains. Water contact angles as high as 178° are achieved. © 2006 Wiley Periodicals, Inc. J Polym Sci Part B: Polym Phys 45: 253–261, 2007.
High red, green, and blue color purity electroluminescence from MEH‐PPV and polyalkyfluorenes‐based bright white polymer light emitting displays
Authors: Lee Rong‐Ho , Lin Kuo‐Tung , Huang Chen‐Yang
Published: December 2006

A series of white polymer light emitting displays (PLEDs) based on a polymer blend of polyalkylfluorenes and poly(2‐methoxy‐5,2′‐ethyl‐hexyloxy‐1,4‐phenylene vinylene) (MEH‐PPV) was developed. MEH‐PPV or red light emitting alkyfluorene copolymer (PFR) was blended with blue light emitting alkyfluorene copolymer (PFB), and MEH‐PPV was blended with both green light emitting alkyfluorene copolymer (PFG) and PFB to generate white light emission PLEDs. Low turn on voltage (2.7 V), high brightness (12,149 nits), high efficiency (4.0 cd/A, 4.0 lm/W), and good color purity (Commission Internationale de L'Eclairage (CIEx,y) co‐ordinates (0.32, 0.34)) were obtained for the white PLEDs based on the PFB and MEH‐PPV polymer blend. Exciplex formation in the interface between PFR and PFB induced a new green emission peak for these two components based white PLEDs. As a result, strong white emission (4078 nits) was obtained by mixing the red, green, and blue (RGB) three primary colors. High color purity of blue (CIE, x = 0.14, y = 0.08), green (CIE, x = 0.32, y = 0.64) and red (CIE, x = 0.67, y = 0.33) emissions was achieved for white PLEDs combining with dielectric interference color‐filters. © 2006 Wiley Periodicals, Inc. J Polym Sci Part B: Polym Phys 45: 330–341, 2007
Morphological change of a diblock copolymer film induced by selective doping of a photoactive chromophore
Authors: Machida Shinjiro , Nakata Hiroshi , Yamada Kazushi , Itaya Akira
Published: December 2006

Tetrakis‐5,10,15,20‐(4‐carboxyphenyl)porphyrine (TCPP) was position‐selectively introduced into a diblock copolymer film of polystyrene‐block‐poly(4‐vinylpyridine) (PS‐b‐P4VP) with a sea–island microphase structure. By immersing the PS‐b‐P4VP film into a solution of TCPP/methanol, TCPP was introduced into the island parts comprising P4VP phase. The morphology of the island parts depended on the immersion time and TCPP concentration. A schematic model for the morphological change caused by the phase‐selective introduction of TCPP was proposed. © 2006 Wiley Periodicals, Inc. J Polym Sci Part B: Polym Phys 45: 368–375, 2007
The nearly constant loss, Johari‐Goldstein β‐relaxation, and α‐relaxation of 1,4‐polybutadiene
Authors: Schroeder Maria J. , Ngai Kia L. , Michael Roland C.
Published: December 2006

From high‐resolution dielectric spectroscopy measurements on 1,4‐polybutadiene (1,4‐PB), we show that in addition to the structural α‐relaxation and higher frequency secondary relaxations in the spectra, a nearly constant loss (NCL) is observed at shorter times/lower temperatures. The properties of this NCL are compared to those of another chemically similar polymer, 1,4‐polyisoprene. The secondary relaxations in 1,4‐PB include the well‐known Johari‐Goldstein (JG) β‐relaxation and two other higher‐frequency peaks. One of these, referred to as the γ‐relaxation, falls between the JG‐relaxation and the NCL. Seen previously by others, this γ‐relaxation in 1,4‐PB is not the JG‐process and bears no relation to the glass transition. At very low temperatures (<15 K), we confirm the existence of a very fast secondary relaxation, having a weak dielectric strength and an almost temperature‐invariant relaxation time. © 2006 Wiley Periodicals, Inc. J Polym Sci Part B: Polym Phys 45: 342–348, 2007
Effect of different ventilation modes with FC‐77 on pulmonary inflammatory reaction in piglets after cardiopulmonary bypass
Authors: Jiang Lijun , Wang Qiang , Liu Yinglong , Du Ming , Shen Xiangdong , Xie Ning , Wu Song
Published: December 2006

Rationale

Cardiopulmonary bypass (CPB) causes pulmonary inflammatory reaction. Liquid ventilation with perfluorocarbon has shown an anti‐inflammatory effect on severely injured lungs. The aim of this study is to investigate the treatment effect of different ventilation modes with perfluorocarbon on pulmonary inflammatory reaction in piglets after CPB.

Methods

After receiving CPB and subsequent infusion of lipopolysaccharide (1 µg/kg), 18 piglets were randomly treated with conventional gas ventilation, total liquid ventilation (TLV), or partial liquid ventilation (PLV) for 240 min. The lung tissue and blood samples were collected at the end of observation period. The pulmonary mRNA expressions and plasmatic concentrations of interleukin‐6 (IL‐6) and interleukin‐8 (IL‐8) were measured. Histological neutrophil count in lung parenchyma was performed.

Results

Hemodynamics, PaCO2 and PH did not differ among groups during the observation period. Both TLV and PLV showed significantly improved oxygenation, reduced pulmonary mRNA expressions and plasmatic levels of IL‐6 and IL‐8, and decreased total neutrophil count in lung parenchyma when compared with conventional gas ventilation. Furthermore, TLV resulted in significantly better oxygenation, lower pulmonary mRNA expressions of IL‐6 and IL‐8, and less total neutrophil count when compared with PLV.

Conclusion

Both TLV and PLV improved oxygenation and reduced pulmonary inflammatory reaction in piglets after CPB, whereas TLV is more effective than PLV. Pediatr Pulmonol. 2007; 42:150–158. © 2006 Wiley‐Liss, Inc.
In whose interests? IT migration in an interconnected world economy
Authors: Millar Jane , Salt John
Published: December 2006

The paper focuses on the interaction between the national management of labour migration flows and the sourcing strategies used by transnational corporations in the IT sector which operate in an increasingly liberalised world economy. Through examination of employer‐sponsored immigration among IT professionals to the UK, it draws attention to the need for migration policy to balance the conflicting interests of employers and resident labour. It combines statistical evidence, largely derived from the UK work permit system, with in‐depth interviews among senior human resource executives. Its main conclusion is that the UK's broad‐brush approach to managed migration is out of touch with the international sourcing policies of firms in the IT sector and has been weak in defending the competitive position of the resident workforce. Copyright © 2007 John Wiley & Sons, Ltd.
A rather benign sexual culture: socio‐sexual lifestyles of youth in urban Central Java, Indonesia
Authors: Ford Nicholas J. , Shaluhiyah Zahroh , Suryoputro Antono
Published: December 2006

Sexuality is clearly a key, if often neglected, dimension for both population and medical geography. The challenge of HIV prevention has given rise to research efforts to understand the pattern and dynamics of sexual lifestyles. This paper reports upon findings from such a study undertaken upon the socio‐sexual lifestyles of youth (18–24 years of age) from factory (low‐income) and university (middle class) social environments in urban Central Java, Indonesia. The study involved a combination of quantitative (2000 person sample survey) and qualitative (8 focus group discussions and 15 in‐depth interviews) methods, with data collected from 2003–2004. Analysis of the basic sexual parameters reveals relatively low levels of pre‐marital sexual experience, but (of concern) very low levels of contraceptive precautions within such activity. The main part of the paper concerns a discussion of a range of young men and women's socio‐sexual lifestyles (identified by cluster analysis). The core Javanese concept of gaul is explored in discriminating different global/traditional orientations. The lifestyles are interpreted in terms of the reflexivity of leisure activities, taste and dress, within the broader contexts of Javanese culture and the social transition occurring in the Republic of Indonesia. Copyright © 2007 John Wiley & Sons, Ltd.
Tunneling anisotropic magnetoresistance effect in a p+‐(Ga,Mn)As/n+‐GaAs Esaki diode
Authors: Ciorga M. , Einwanger A. , Sadowski J. , Wegscheider W. , Weiss D.
Published: December 2006

We have performed magnetotransport experiments on p+‐(Ga,Mn)As/n+‐GaAs Esaki diode devices. The spin‐valve‐like signal was observed in these devices in an in‐plane magnetic field configuration due to Tunneling Anisotropic Magnetoresistance effect. The pattern of the observed magnetic reversal process strongly depends on the observed magnetic anisotropy of the (Ga,Mn)As layer – depending on its type the sign of the spin‐valve‐like signal can be changed by a simple rotation of the magnetic field by 90° or not. The type of the anisotropy is found to be strongly shaped, in a random way, during processing of the wafer. (© 2007 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Role of defects on the magnetic interactions in Mn‐doped ZnO
Authors: Iuşan Diana , Sanyal Biplab , Eriksson Olle
Published: December 2006

Oxide based diluted magnetic semiconductors are highly controversial from the point of view of intrinsic ferromagnetism brought in by doping with transition metal ions. By ab‐initio Korringa–Kohn–Rostoker‐Coherent‐Potential‐Approximation (KKR‐CPA) calculations in the framework of density functional theory, we have obtained the electronic structure and magnetic exchange interaction parameters of Mn‐doped ZnO in the presence and absence of several types of defects. A weak antiferromagnetic exchange interaction is observed in pure Mn‐doped ZnO in the dilute limit with an increase in the strength of interactions with increasing concentration of Mn. In the presence of donor defects, such as oxygen vacancies and interstitial Zn, the interactions remain antiferromagnetic whereas in case of acceptor defects like Zn vacancies and N substitution of O, ferromagnetic interactions are observed. We have used the ab‐initio exchange parameters in Monte‐Carlo simulations for calculating finite temperature properties. Due to the short ranged behavior of interactions and disorder effects, the Curie temperatures calculated from Monte Carlo simulations show moderate values, not exceeding 50 K when the Mn content is 5%. (© 2007 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Comparative study of Mn and Fe incorporation into GaN by metalorganic chemical vapor deposition
Authors: Kane M. H. , Gupta S. , Fenwick W. E. , Li N. , Park E.‐H. , Strassburg M. , Ferguson I. T.
Published: December 2006

Wide bandgap diluted magnetic semiconductors (DMS) have been of interest recently due to theoretical predictions of room temperature ferromagnetism in these materials. However, the mechanism of the observed ferromagnetism of the nitrde‐based DMS is still controversial, and may originate from a carrier‐mediated, defect‐related or nanoscale clustering mechanism. In this work, we present a comparative study of the incorporation of various transition metals and their effect on the optical, structural, and magnetic properties of GaN. Metal‐organic chemical vapor deposition (MOCVD) has been employed to produce epitaxial films of varying thickness and manganese and iron concentrations using bis‐cyclopentyldienyl (magnanese, iron) as the transition metal sources. High‐resolution X‐ray diffraction reveals no macroscopic secondary phases under optimized growth conditions. Magnetic hysteresis is observed at room temperature in both Ga1–x Mnx N and Ga1–x Fex N, though the strength of the magnetic ordering is roughly an order of magnitude weaker in the Fe‐alloyed samples. Increasing Mn concentrations significantly affects the long‐range lattice ordering, and the observation of local vibrational modes (LVMs) supports the formation of nitrogen vacancies, even under optimized MOCVD growth conditions. Such vacancies form shallow donor complexes and thus contribute to self‐compensation. Disorder‐induced modes at 300 cm–1 and 710 cm–1 and a LVM due to vacancies at 669 cm–1 were revealed by Raman spectroscopy. The iron‐doped samples also show the disorder‐induced modes, but the vacancy‐related mode is not observed which is attributed to Fermi level and defect formation energy considerations. (© 2007 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Optical and magneto‐optical properties of ZnMnO and ZnMnFeO single crystals and thin films
Authors: Savchuk A. I. , Fediv V. I. , Kleto G. I. , Krychun S. V. , Savchuk S. A.
Published: December 2006

Single crystals of oxide diluted magnetic semiconductor Zn1–x Mnx O have been grown by chemical vapour transport and thin films of Zn1–x Mnx O, Zn1–x –y Mnx Fey O have been deposited by pulsed laser ablation and rf magnetron sputtering methods. Optical absorption spectra of the obtained crystals and films have features associated with band‐to‐band direct type transitions and d–d crystal‐field transitions due to presence of Mn2+ ions. The observed peculiarities of the Faraday rotation for Zn1–x Mnx O crystals and films suggest of paramagnetic behaviour. In contrast, Zn1–x –y Mnx Fey O film samples exhibit ferromagnetic‐like behaviour which is confirmed on typical magnetic field dependence of the Faraday rotation at room temperature. (© 2007 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Competing magnetic phases of Mn5Ge3 compound
Authors: Stroppa Alessandro , Peressi Maria
Published: December 2006

Germanium‐based compounds have recently attracted considerable attention in Semiconductor Spintronics. The Mn5Ge3 compound have been grown on Ge(111) substrate so that epitaxial “spin valves” can be fabricated. Recent experiments suggest a spin structure that is likely non‐collinear. In order to gain deep insights into the magnetic structure of this compound, we have performed fully unconstrained ab‐initio pseudo‐potential calculations within spin density functional theory. We have considered several possible magnetic configurations: paramagnetic (PM), collinear (C) ferromagnetic (FM) and anti‐ferromagnetic (AFM), non‐collinear (NC) spin configurations. We first study the effect of the pressure. At equilibrium volume (V eq = 0.203 m3), the C‐FM and NC self‐consistent solutions (which have different magnetic states) are competing phases. For V ≃ 1.1V eq there is a crossover of the C‐FM and C‐AFM curves, with the C‐AFM becoming favourite with respect to C‐FM for larger volumes. Finally, we have studied the effect of strain field. Interestingly, the degeneracy of the NC phase with the C‐spin configurations (FM and AFM) is definitely removed under the effect of uniaxial structural distortions (NC spin configuration is favoured under tensile uniaxial strain). (© 2007 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
The growth of Cr‐doped GaN by MOVPE towards spintronic applications
Authors: Cho Y. S. , Kaluza N. , Guzenko V. , Schäpers Th. , Hardtdegen H. , Bochem H.‐P. , Breuer U. , Ghadimi M. R. , Fecioru‐Morariu M. , Beschoten B. , Lüth H.
Published: December 2006

This paper reports on the growth of Cr‐doped GaN layers by metal organic vapor phase epitaxy (MOVPE) and their characterization for possible spintronic applications. We have used bis (cyclopentadienyl)chromium (Cp2Cr) to intentionally incorporate chromium (Cr) during GaN layer growth. The effects of the carrier gas, hardware setup, and growth temperature on the growth of Cr‐doped GaN were investigated. A linear dependence between mole fraction of Cp2Cr in the gas phase and incorporated Cr in the solid phase was found. The surface morphology was mostly influenced by carrier gas and growth temperature. A remanent magnetization was observed even above room temperature. (© 2007 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Raman studies of ZnO:Co thin films
Authors: Zhou Huijuan , Chen Limei , Malik Vivek , Knies Christoph , Hofmann Detlev M. , Bhatti Kanwal Preet , Chaudhary S. , Klar Peter J. , Heimbrodt Wolfram , Klingshirn Claus , Kalt Heinz
Published: December 2006

In this paper we investigate cobalt doped ZnO thin films prepared via different sol–gel methods. XRD shows only the diffraction peaks from wurtzite ZnO without secondary phase, as widely reported in literature, for the Co contents of our samples of 3 to 12%. Raman spectroscopy reveals the existence of antiferromagnetic cobalt oxides like CoO and Co3O4 already in intermediately doped samples. Furthermore, the Raman shifts of the doped samples exhibit a shift to higher energy with increasing Co doping content. Unfortunately, Raman spectroscopy is not sensitive to metallic Co and, therefore, cannot be employed to explore the presence of Co clusters. However, we demonstrate that XRD is not a suitable method to rule out the existence of magnetic secondary phases in ZnO doped with transition metals. (© 2007 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Magneto‐optical spectroscopy of spin injection and spin relaxation in ZnMnSe/ZnCdSe and GaMnN/InGaN spin light‐emitting structures
Authors: Buyanova I. A. , Chen W. M. , Oka Y. , Abernathy C. R. , Pearton S. J.
Published: December 2006

In this paper we review our recent results from in‐depth investigations of physical mechanisms which govern efficiency of several processes important for future spintronic devises, such as spin alignment within diluted magnetic semiconductors (DMS), spin injection from DMS to non‐magnetic spin detectors (SDs) and also spin depolarization within SD. Spin‐injection structures based on II–VIs (e.g. ZnMnSe/Zn(Cd)Se) and III–Vs (e.g. GaMnN/Ga(In)N) were studied as model cases. Exciton spin relaxation within ZnMnSe DMS, important for spin alignment, was found to critically depend on Zeeman splitting of the exciton states and is largely facilitated by involvement of longitudinal optical (LO) phonons. Optical spin injection in ZnMnSe/Zn(Cd)Se was shown to be governed by (i) commonly believed tunneling of individual carriers or excitons and (ii) energy transfer via localized excitons and spatially separated localized electron–hole pairs (LEHP) located within DMS. Unexpectedly, the latter mechanism is in fact found to dominate spin injections. We shall also show that spin depolarization in the studied structures is essentially determined by ef‐ ficient spin relaxation within non‐magnetic spin detectors, which is an important factor limiting efficiency of spin detection. Detailed physical mechanisms leading to efficient spin depolarization will be discussed. (© 2007 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Dynamics of spin interactions in diluted magnetic semiconductor heterostructures
Authors: Yakovlev D. R.
Published: December 2006

This paper gives an overview of the recent studies of spin dynamics in diluted magnetic semiconductor heterostructures based on (Zn,Mn)Se and (Cd,Mn)Te. The spin dynamics is controlled by energy and spin transfer between systems of magnetic ions, lattice (phonon system) and free carriers. Spin–lattice relaxation time of the Mn spin system is a very strong function of the Mn content, it decreases by five orders of magnitude when the Mn content changes from 0.4 to 11%. Additionally this time can be tuned by the varying free carrier concentration and by the growth of heteromagnetic structures with inhomogeneous profile of Mn ions. (© 2007 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Structural and magnetic properties of GeMn layers; High Curie temperature ferromagnetism induced by self organized GeMn nano‐columns
Authors: Devillers T. , Jamet M. , Barski A. , Poydenot V. , Dujardin R. , Bayle Guillemaud P. , Rothman J. , Bellet Amalric E. , Cibert J. , Mattana R. , Tatarenko S.
Published: December 2006

In this paper we report on the structural and magnetic properties of GeMn layers grown on Ge(001). We show that for the optimized Mn concentration (6%) and for optimized growth temperature (close to 130 °C), GeMn samples exhibit a high Curie temperature (higher than 400 K) and Anomalous Hall Effect up to room temperature. Our GeMn layers grown at low temperature (70 °C to 130 °C) are composed of vertical Mn‐rich nano‐colums. Samples grown at temperatures higher than 130 °C contain GeMn nanoclusters. (© 2007 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Role of hyperfine interaction on electron spin optical orientation in charge‐controlled InAs–GaAs single quantum dots
Authors: Krebs O. , Eble B. , Lemaître A. , Urbaszek B. , Kowalik K. , Kudelski A. , Marie X. , Amand T. , Voisin P.
Published: December 2006

We report on electron spin physics in a single charge‐tunable self‐assembled InAs/GaAs quantum dot. The hyperfine interaction between the optically oriented electron and nuclear spins leads to the polarization of the quantum dot nuclei. The sign of the resulting Overhauser‐shift depends on the trion state X+ or X–, and remarkably its strength does not vanish in zero magnetic field. This explains the quenching of X+ spin relaxation under steady‐state excitation polarization. (© 2007 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Hybrid image‐based collision detection in Java 3D
Authors: Xiao Gaoyu , Aziz Aamer , Nowinski Wieslaw L.
Published: December 2006

Collision detection is highly important in computer graphics and virtual reality. Most collision detection methods are object‐based, relying on testing the geometrical interference of objects, and their performance therefore depends on the geometrical complexity of the objects. Recently, image‐based methods have gained increasing acceptance for their simplicity in implementation, robustness with respect to the object geometry, and the potential to distribute the computational burden onto graphics hardware. However, all existing image‐based methods require direct calls to OpenGL, but so far there is no direct way to access OpenGL through the Java 3D API. Although Java 3D provides its own built‐in collision detection classes, they are either incorrect or inefficient. In this paper, we present a hybrid image‐based collision detection method in Java 3D, which incorporates the Java 3D built‐in collision detection and the image‐based collision detection in our specially devised scene graph. In addition, we take advantage of the fact that the 3D position of successive offscreen views (i.e. virtual views perceived by the probing object) does not change significantly and thereby reduce the occurrences of offscreen rendering, so that the collision detection becomes even faster (up to 50% in our case). Experimental results prove the correctness and efficiency of our method. Copyright © 2006 John Wiley & Sons, Ltd.
High‐error approximate dictionary search using estimate hash comparisons
Authors: Rönnblom Johan
Published: December 2006

A method for finding all matches in a pre‐processed dictionary for a query string q and with at most k differences is presented. A very fast constant‐time estimate using hashes is presented. A tree structure is used to minimize the number of estimates made. Practical tests are performed, showing that the estimate can filter out 99% of the full comparisons for 40% error rates and dictionaries of up to four million words. The tree is found to be efficient up to a 50% error rate. Copyright © 2006 John Wiley & Sons, Ltd.
Automated bug isolation via program chipping
Authors: Sterling Chad D. , Olsson Ronald A.
Published: December 2006

This paper introduces program chipping, a simple yet effective technique to isolate bugs. This technique automatically removes or chips away parts of a program so that the part that contributes to some symptomatic output becomes more apparent to the user. Program chipping is similar in spirit to traditional program slicing and debugging techniques, but chipping uses very simple techniques based on the syntactic structure of the program. We have developed a chipping tool for Java programs, called ChipperJ, and have run it on a variety of small to large programs, including a Java compiler, looking for various symptoms. The results are promising. The reduced program is generally about 20–35% of the size of the original. ChipperJ takes less than an hour on large programs to perform this reduction; even if it took overnight, that would be reasonable if it saves the developer time. Copyright © 2006 John Wiley & Sons, Ltd.
A simplified analysis and vibration control to super‐high‐rise buildings
Authors: Takabatake Hideo , Satoh Tetsuya
Published: December 2006

This paper clarifies the following four points on the dynamic behavior of super‐high‐rise buildings of 700m high consisting of doubly symmetric frame‐tubes with or without braces. A simple and accurate analytical method presented by Takabatake (1996) is shown to be very useful for the preliminary design of such a mega‐structure. The building is replaced by an equivalent rod which may allow the main deformation field composed of longitudinal deformation, bending, transverse shear deformation, and shear‐lag. It is pointed out originally that, after the horizontal component of earthquake ground motion fades away, noticeable swell breaks out for a long time and that phenomenon is undamping. The serious phenomenon of swell increases remarkably in addition to the action of the horizontal component of an earthquake wave having a long period. The effect of soil–structure interaction on such a structure is discussed using a general analytical method proposed here. An epochal method both to reduce the dynamic response and to leave out the undamping swell after earthquake action is proposed and its effectiveness as a device for vibration control is demonstrated through the numerical computation. Copyright © 2006 John Wiley & Sons, Ltd.
Influence of design procedures on the seismic response of bi‐eccentric plan‐asymmetric systems
Authors: Ghersi A. , Rossi P. P.
Published: December 2006

This paper investigates, by means of idealized one‐storey models, the seismic behaviour of bi‐eccentric plan‐asymmetric structures and the influence of different design practices on it. All the examined design procedures are based on the use of modal analysis, in order to grant, in any case, a reliable estimate of the elastic response. The first procedure requires the standard application of modal analysis (nominal positions of mass and stiffness centres), while the others employ a double application of the same analysis to reduce the ductility demand in occurrence of strong ground motions. Furthermore, within the aforementioned procedures, the importance and effectiveness of the combination of design internal forces induced by two orthogonal seismic components are discussed. In order to obtain statistically representative information on the structural response to seismic loads the models are subjected to a set of 30 bidirectional accelerograms. A wide parametric analysis allows observations and conclusions, which may be considered reliable for asymmetric models characterized by a wide range of values of the structural parameters. Copyright © 2006 John Wiley & Sons, Ltd.
Self‐concept and science achievement: Investigating a reciprocal relation model across the gender classification in a crosscultural context
Authors: Wang Jianjun , Oliver J. Steve , Staver John R.
Published: December 2006

Science achievement and self‐concept are articulated in this study to examine a model of reciprocal relationship during a crosscultural transition. Trend data have been gathered to assess changes of the perceived English importance before and after Hong Kong's sovereignty handover from Britain to China. The data analyses were conducted four times across dimensions of gender and timing over which the political transition took place. Besides small gender differences in the statistical results, weak but significant reciprocal relationships have been found between science achievement and self‐concept. In line with a policy of switching the medium of instruction from English to Chinese in most secondary schools, interpretation of different path coefficients obliges incorporation of cross‐cultural understanding in science education. © 2006 Wiley Periodicals, Inc. J Res Sci Teach 45: 711–725, 2008
An engineering process for the verification of real-time systems
Authors: Burns A. , Lin T. -M.
Published: December 2006

The complete verification of the timing properties of a large critical system cannot be undertaken in a single step or with a single method. In this paper we present a process that links together a number of techniques and approaches that cover all stages of development from requirements analysis to code testing. The key elements of the process are: a constrained form of timed automata that uses
delay
and
deadline
to define temporal behaviour, notions of
rely
and
guarantee
to cover temporal dependencies, model checking for design verification, SPARK and Ravenscar restrictions for programming, and scheduling and response time analysis for asserting implementation compliance. Extended examples of the use of the process are given.
Parathyroid Cyst: Often Mistaken for a Thyroid Cyst
Authors: Ujiki Michael B. , Nayar Ritu , Sturgeon Cord , Angelos Peter
Published: December 2006

Introduction

Parathyroid cysts are rare but clinically significant lesions. They can be functional, mistaken for a thyroid cyst, and/or managed nonoperatively on occasion.

Methods

We identified seven patients (1 male, 6 females) with the diagnosis of parathyroid cyst from 1998 to 2003.

Results

Altogether, 33% of the patients had functional cysts. Sestamibi scans were performed in three of the seven patients, including two with functional cysts; none showed focal uptake. In toto, six of the seven cysts (86%) were found in an inferior parathyroid gland. All of the cysts had crystal‐clear aspirate. C‐terminal parathormone (PTH) levels were obtained from the aspirate from five of the seven (71%) patients. The mean level was 269,736 pg/ml (1970–1,268,074 pg/ml). Surgery was performed in three of the seven (43%) patients. All patients who underwent surgery improved postoperatively based on symptoms and serum levels of calcium and PTH. The four patients (57%) who were treated nonoperatively were subjected to aspiration alone; three (75%) of those patients required multiple aspirations.

Conclusions

Most parathyroid cysts are nonfunctional and are rarely symptomatic. They are usually located in an inferior gland. If aspirated, most of the cysts reaccumulate fluid. Operative management is usually straightforward and alleviates symptoms and any biochemical abnormalities caused by the cyst.
Clinical Outcomes of Ultrasound-Guided Aspiration and Lavage in Calcific Tendinosis of the Shoulder
Authors: Lin Julie T. , Adler Ronald S. , Bracilovic Ana , Cooper Grant , Sofka Carolyn , Lutz Gregory E.
Published: December 2006

Objective

To determine the effectiveness of ultrasound-guided aspiration and lavage in the treatment of patients with calcific tendinosis of the shoulder.

Materials and methods

Retrospective chart review resulted in 44 patients who were identified as having received ultrasound-guided aspiration of calcific tendinosis of the shoulder between 2000 and 2003. Of these, 36 patients were interviewed by telephone for pre- and posttreatment assessment of pain, shoulder function, prior shoulder surgery, injury, and prescribed treatment modalities with a follow-up time of 8 months to 3.1 years (mean = 22.5 months). L'Insalata score, numeric rating scale (NRS), and patient satisfaction score served as outcome measures.

Results

Our criteria for a successful outcome included (1) 12-point or greater improvement in the L'Insalata shoulder rating questionnaire, (2) 2-point or greater improvement in the NRS, (3) patient satisfaction rating of “good”, “very good”, or “excellent”, (4) patients’ willingness to undergo the procedure again if they experienced recurrent symptoms, and (5) 1 month or less of analgesic medication use after the aspiration procedure. We determined that ultrasound-guided aspiration of calcific tendinosis of the shoulder resulted in a successful outcome for 75% (27/36) of patients with a mean 20.2-point improvement in the L'Insalata shoulder rating questionnaire score and a mean 6.4-point improvement in the NRS ( p < 0.01). Conclusion: This retrospective study suggests that ultrasound-guided aspiration and lavage of calcific shoulder deposits appears to be an efficacious therapeutic modality for treatment of calcific tendinosis. Further studies involving prospective randomized controlled trials would be helpful to further assess the long-term efficacy of this procedure as a minimally invasive treatment for calcific tendinosis of the shoulder.
Hydrophobic polymers for liquid cleaning formulations
Authors: Carrier Allen M. , Rodrigues Klein A. , Crossman Martin C.
Published: December 2006

A patented method to provide acrylic acid:styrene (AA:Sty) copolymers with a variety of AA:Sty mole ratios is described. This method allows the polymer to be provided as a solution in water with up to 50 mol% styrene. The addition of significant amounts of styrene provides increased polymer solubility in liquid laundry detergents without sacrificing the traditional benefits of typical polycarboxylates. Studies were run in a Tergotometer and full‐scale U.S. washing machine, showing particulate soil antiredeposition performance equivalent to poly(acrylic acid) with a molecular weight of 4500 and improved oily soil antiredeposition. The dry polymer is soluble in several glycols, a behavior not typically seen with polycarboxylates.
New process for the production of branched‐chain fatty acids
Authors: Zhang Zongchao Conrad , Dery Maurice , Zhang Shuguang , Steichen Dale
Published: December 2006

Fatty acids are the primary natural starting materials for the production of surfactant and detergent molecules. Derived from vegetable (oil) and animal (fat) triglyceride sources, the fatty acids are linear aliphatic carboxylic acids. Industrial interest in branched‐chain fatty acids is driven by the needs for products with enhanced performance benefits including higher solubility, ease of handling, better hard water tolerance, and improved oxidative stability. Therefore, catalytic processes have been developed for the conversion of linear fatty acids to branched ones. High yields of branched acids are obtained from unsaturated fatty acids over acidic zeolites, particularly those with large pores. Fatty esters also are readily isomerized to branched ones by means of the same catalyst and process. It is postulated that the isomerization of fatty acids proceeds through three‐ and four‐membered ring carbocation intermediates formed inside the largepore zeolites. This is supported by evidence of methyl and ethyl branching in the primary and final products. The total number of carbon atoms in the fatty acid molecule is unchanged. Surfactants derived from branched fatty acids show favorable physical properties, including a lower viscosity and improved handling, even as intended performance characteristics are maintained.
Nuclear magnetic resonance studies on hydrolysis kinetics and micellar growth in solutions of surface‐active betaine esters
Authors: Lundberg Dan , Holmberg Krister
Published: December 2006

A series of surface‐active betaine esters of medium‐ to long‐chain alcohols has been synthesized. The hydrophobic parts used were decyl, dodecyl, tetradecyl, and oleyl chains. Ethyl betainate was prepared as a non‐surface‐active reference compound. The surfactants were characterized by critical micellization concentration (CMC), and base‐catalyzed hydrolysis was studied by using 1H nuclear magnetic resonance (NMR). Micellar catalysis was shown to have a strong influence on the hydrolysis. This means that the hydrolysis rates are concentration dependent. For dodecyl betainate, the effect of the degradation products (dodecanol and betaine) on the micellar shape was investigated by NMR diffusion experiments. The degradation products were shown to induce micellar growth.