bluuebunny/crossref_metadata_2025 huggingface dataset:
Some Notes on the Caspian Energy and Ethnic Conflicts in the Caucasus
Authors: Mousavi Mohammad
Published: June 2010

In the past two decades, the transportation of Caspian oil and gas resources to the international markets has been one of the most controversial and pressing issues in regional politics. Possibly, this is due to the fact that it is more than just an economic problem, having also a visible security and geopolitical aspect. Hence, pipeline competition has fuelled both rivalry and cooperation among existing and potential transit countries. Particularly, the routes through the Caucasus are the most problematic, as the transit corridors through Russia, Azerbaijan Republic, Georgia, and further Turkey have faced with various ethnic conflicts in these countries. In the 1990s, these conflicts played a crucial role in increasing the risk of Caspian oil transit through the Caucasus and Russia. The ethnicities in this region have used the pipeline politics more as a bargaining chip vis-à-vis their central governments for a better position, and less as a pretext for separation. The international political environment, such as the September 11 attack on the U.S. soil and the following global “war on terror” led by the United States, have already undermined such ethnic bargaining power against the governments and have shifted the separatist trends to an inferior position. This paper is a brief re-examination of the situation concerning the energy transit and the ethnic conflicts in the region.
Protease-activated Receptor-2 (par2) in Human Periodontitis
Authors: Holzhausen M. , Cortelli J.R. , da Silva V. Araújo , Franco G.C. Nobre , Cortelli S. Cavalca , Vergnolle N.
Published: June 2010

No evidence for the role of protease-activated receptor-2 (PAR2) in human periodontal disease has been demonstrated so far. Thus, we sought to investigate the expression of PAR2mRNA in chronic periodontitis, and to examine whether its expression is related to the presence of PAR2potential activators. Microbiological and gingival crevicular fluid samples were collected from individuals with chronic periodontitis and control individuals, and the presence of neutrophil serine proteinase 3 (P3) and Porphyromonas gingivalis was evaluated. PAR2mRNA expression was higher (p < 0.001) in those with chronic periodontitis compared with control individuals, and it was statistically decreased (p = 0.0006) after periodontal treatment. Furthermore, those with chronic periodontitis presented higher (p < 0.05) levels of IL-1α, IL-6, IL-8, and TNF-α, total proteolytic activity, P. gingivalis prevalence, and P3mRNA expression compared with control individuals. We conclude that PAR2mRNA expression and its potential activators are elevated in human chronic periodontitis, therefore suggesting that PAR2may play a role in periodontal inflammation.
Experiences of falling in love: Investigating culture, ethnicity, gender, and speed
Authors: Riela Suzanne , Rodriguez Geraldine , Aron Arthur , Xu Xiaomeng , Acevedo Bianca P.
Published: June 2010

This research investigated 12 precursors to falling love — reciprocal liking, appearance, personality, similarity, familiarity, social influence, filling needs, arousal, readiness, specific cues, isolation, and mysteriousness — with respect to culture, ethnicity, gender, and speed. In Study 1, White-American and Asian-American participants wrote narratives of their falling in love experiences. In Study 2, participants from the United States and China wrote narratives and completed self-ratings of the precursors. Few ethnic, gender, and speed differences were obtained in either study, but those found were in the predicted direction. Many cultural differences were found in Study 2, the majority of which were consistent with individualism-collectivism models. Implications for understanding falling in love and directions for future research are discussed.
Monitoring of low molecular weight heparin anticoagulation during haemodialysis with a Sonoclot Analyzer
Authors: Schött Ulf , Nilsson Lars Göran , Broman Marcus , Engström Martin
Published: June 2010

Objectives: Sonoclot was used in this study to monitor low molecular weight heparin (LMWH) during haemodialysis.

Material and Methods: Two different intravenous doses (standard / half-dose) of dalteparin were studied in eight patients. Blood was sampled for coagulation analyses with Sonoclot, thrombin-antithrombin (TAT) and anti-Xa. A visual fibrin deposition score (VFS) in the venous drip chamber was also evaluated.

Results: All patients completed their dialysis. There was a progressive increase in TAT levels, which correlated to the dalteparin dose. Significant differences (p<0.05) were found for TAT, VFS and Sonoclot celite-activated clotting time (SonACT) between the different LMWH dosages. TAT and Sonoclot correlated to each other, but not to the VFS. SonACT was significantly increased at two hours, with the high dalteparin dose compared to the lower dose.

Conclusion: Both Sonoclot and TAT failed to predict the VFS. No patient had any clinical clotting events and all dialyses were completed successfully.
Preoperative therapeutic programme for elderly patients scheduled for elective abdominal oncological surgery: a randomized controlled pilot study
Authors: Dronkers JJ , Lamberts H. , Reutelingsperger IMMD , Naber RH , Dronkers-Landman CM , Veldman A. , van Meeteren NLU
Published: June 2010

Objective: Investigation of the feasibility and preliminary effect of a short-term intensive preoperative exercise programme for elderly patients scheduled for elective abdominal oncological surgery.

Design: Single-blind randomized controlled pilot study.

Setting: Ordinary hospital in the Netherlands.

Subjects: Forty-two elderly patients (>60 years).

Interventions: Patients were randomly assigned to receive a short-term intensive therapeutic exercise programme to improve muscle strength, aerobic capacity, and functional activities, given in the outpatient department (intervention group; n =22), or home-based exercise advice (control group; n=20).

Main measures: Parameters of feasibility, preoperative functional capacity and postoperative course.

Results: The intensive training programme was feasible, with a high compliance and no adverse events. Respiratory muscle endurance increased in the preoperative period from 259 ± 273 to 404 ± 349 J in the intervention group and differed significantly from that in the control group (350 ± 299 to 305 ± 323 J; P<0.01). Timed-Up-and-Go, chair rise time, LASA Physical Activity Questionnaire, Physical Work Capacity and Quality of Life (EORTC-C30) did not reveal significant differences between the two groups. There was no significant difference in postoperative complications and length of hospital stay between the two groups.

Conclusion: The intensive therapeutic exercise programme was feasible and improved the respiratory function of patients due to undergo elective abdominal surgery compared with home-based exercise advice.
Transient inactivation of the infralimbic cortex induces antidepressant-like effects in the rat
Authors: Slattery David A , Neumann Inga D , Cryan John F
Published: June 2010

Affective disorders are among the main causes of disability worldwide, yet the underlying pathophysiology remains poorly understood. Recently, landmark neuroimaging studies have shown increased metabolic activity in Brodmann Area 25 (BA25) in depressed patients. Moreover, functional inactivation of this region using deep brain stimulation alleviated depressive symptoms in severely depressed patients. Thus, we examined the effect of a similar manipulation, pharmacological inactivation of the infralimbic cortex, the rodent correlate of BA25, in an animal model of antidepressant activity: the modified rat forced swim test. Transient inactivation of the infralimbic cortex using muscimol reduced immobility, an antidepressant-like effect in the test. Importantly, this activity was not the result of a general increase in locomotor activity. Activation of the infralimbic cortex using bicuculline did not alter behaviour. Finally, we examined the effect of muscimol in animals bred for high anxiety-related behaviour, which also display elevated depression-related behaviour. Transient inactivation of the infralimbic cortex decreased the high inborn depression-like behaviour of these rats. These results show that it is possible to replicate findings from a clinical trial in a rodent model. Further, they support the use of the forced swim test to gain greater understanding of the neurocircuitry involved in depression and antidepressant-action.
Learning from Demonstration for Autonomous Navigation in Complex Unstructured Terrain
Authors: Silver David , Bagnell J. Andrew , Stentz Anthony
Published: June 2010

Rough terrain autonomous navigation continues to pose a challenge to the robotics community. Robust navigation by a mobile robot depends not only on the individual performance of perception and planning systems, but on how well these systems are coupled. When traversing complex unstructured terrain, this coupling (in the form of a cost function) has a large impact on robot behavior and performance, necessitating a robust design. This paper explores the application of Learning from Demonstration to this task for the Crusher autonomous navigation platform. Using expert examples of desired navigation behavior, mappings from both online and offline perceptual data to planning costs are learned. Challenges in adapting existing techniques to complex online planning systems and imperfect demonstration are addressed, along with additional practical considerations. The benefits to autonomous performance of this approach are examined, as well as the decrease in necessary designer effort. Experimental results are presented from autonomous traverses through complex natural environments.
Randomized, controlled trial of telcagepant over four migraine attacks
Authors: Ho Andrew P , Dahlöf Carl GH , Silberstein Stephen D , Saper Joel R , Ashina Messoud , Kost James T , Froman Samar , Leibensperger Heather , Lines Christopher R , Ho Tony W
Published: June 2010

Methods: This study evaluated the calcitonin gene-related peptide (CGRP) receptor antagonist telcagepant (tablet formulation) for treatment of a migraine attack and across four attacks. Adults with migraine were randomized, double-blind, to telcagepant 140 mg, telcagepant 280 mg, or control treatment sequences to treat four moderate-to-severe migraine attacks. Control patients received placebo for three attacks and telcagepant 140 mg for one attack. Efficacy for the first attack (Attack 1) and consistency of efficacy over multiple attacks were assessed. For an individual patient, consistent efficacy was defined as ≥3 successes, and lack of consistent efficacy was defined as ≥2 failures, in treatment response. A total of 1677 patients treated ≥1 attack and 1263 treated all four attacks.

Results: Based on Attack 1 data, telcagepant 140 mg and 280 mg were significantly ( p < .001) more effective than placebo for 2-hour pain freedom, 2-hour pain relief, 2-hour absence of migraine-associated symptoms (phonophobia, photophobia, nausea), and 2–24 hours sustained pain freedom. The percentage of patients with 2-hour pain freedom consistency and 2-hour pain relief consistency was significantly ( p < .001) higher for both telcagepant treatment sequences versus control. Adverse events within 48 hours for telcagepant with an incidence ≥2% and twice that of placebo were somnolence (placebo = 2.3%, 140 mg = 5.9%, 280 mg = 5.7%) and vomiting (placebo = 1.4%, 140 mg = 1.0%, 280 mg = 2.9%).

Conclusion: Telcagepant 140 mg and 280 mg were effective for treatment of a migraine attack and were more consistently effective than control for intermittent treatment of up to four migraine attacks. Telcagepant was generally well tolerated. (Clinicaltrials.gov; NCT00483704)
Psychosocial headache measures in Caucasian and African American headache patients: Psychometric attributes and measurement invariance
Authors: Heckman Bernadette Davantes , Berlin Kristoffer S , Watakakosol Rewadee , Pierre Valessa St.
Published: June 2010

Introduction: As research increasingly examines differences in headache characteristics between Caucasian and African American headache patients, it is requisite to determine the equivalence of existing headache measures for both racial groups.

Methods: This study examined the psychometric properties and measurement invariance of four widely used psychosocial headache measures. Caucasians ( N = 173) and African Americans ( N = 114) receiving treatment in four headache subspecialty clinics throughout Ohio completed the Headache Disability Inventory (HDI), the Migraine-Specific Quality of Life (MSQL) measure, the Headache Management Self-Efficacy (HMSE) scale, and the Headache-Specific Locus of Control (HSLC) scale prior to initiating new preventive therapies.

Conclusion: All measures demonstrated good internal consistency and measurement invariance. Despite adequate measurement invariance, the recommended factor structure of the HMSE scale yielded a poor fit for both African American and Caucasian patients. With perhaps the exception of the HMSE scale, the HDI, MSQL scale and HSLC scale are psychometrically sound and can be used with both Caucasian and African American headache patients.
Influence of predialysis comorbidity and damage accrual on mortality in lupus patients treated with peritoneal dialysis
Authors: Liang C-C. , Lin H-H. , Wang I-K. , Kuo H-L. , Liu J-H. , Yeh H-C. , Chang C-T. , Yen T-H. , Hung C-C. , Huang C-C.
Published: June 2010

Objective: Although there have been many studies on systemic lupus erythematosus (SLE) patients, there are few data about survival analysis of lupus patients receiving dialysis. Therefore, the objective of this study is to analyze risk factors predicting mortality in lupus patients treated with peritoneal dialysis (PD). In addition, we also delineate the relationship between predialysis comorbid illnesses, damage accrual, and mortality in lupus patients undergoing PD. Methods: This longitudinal cohort study included 38 lupus patients undergoing PD between 1990 and 2008. The clinical parameters, disease activity (non-renal SLEDAI, nrSLEDAI), comorbid illnesses, and damage accrual were collected. We applied the Charlson Comorbidity Index (CCI), Khan Index, and Davies Index to elucidate the impact of predialysis comorbidity on mortality. Moreover, we examined prognostic value of predialysis SDI (Systemic Lupus International Collaborating Clinics Disease Damage Index) for lupus PD patients. Results: There were 33 women and five men included for analysis. The mean age at PD entry was 32.2 ± 10.4 years and mean duration of PD was 39.7 ± 22.4 months. The nrSLEDAI score during PD significantly decreased, compared to the predialysis one (2.13 ± 2.09 vs. 4.00 ± 3.08, p < 0.001). All comorbidity indices and SDI scores were significantly and positively correlated with each other (p < 0.001). Univariate Cox regression analysis showed that serum creatinine level, date at PD entry, and the CCI were predictors for mortality. The predialysis nrSLEDAI and SDI scores did not have roles in predicting mortality of lupus PD patients. Conclusions: The predialysis CCI, instead of SDI, determines an increased risk for mortality in lupus patients treated with PD. The prognosis of lupus patients treated with PD largely depends on the severity of predialysis comorbidity, especially cardiovascular diseases.
Target silencing of disease-associated B-lymphocytes by chimeric molecules in SCID model of pristane-induced autoimmunity
Authors: Dimitrova I. , Gesheva V. , Nikolova K. , Mihaylova N. , Todorov T. , Nikolova M. , Tchorbanov A.
Published: June 2010

Systemic lupus erythematosus (SLE) is an autoimmune disease characterized by the generation of autoantibodies against a diverse array of self-antigens. The B cells producing immunoglobulin G (IgG) antibodies to double-stranded DNA appear to play a main role in the disease progression. Their specific elimination is a reasonable mechanism for effective therapy of SLE. The presently used approaches for silencing autoreactive disease-associated B cells are nonspecific and more precise therapies are needed. We have previously constructed a chimeric protein molecule consisting of several DNA-mimotope peptides coupled to a rat monoclonal anti-mouse CD32 (FcγRIIb) antibody. The mineral oil pristane induces a lupus-like syndrome in non-autoimmune mice leading to the development of glomerulonephritis and lupus-associated autoantibodies. In the present paper, using a pristane-induced autoimmune model in SCID mice, we analyzed the ability of the chimeric antibody to suppress selectively the autoreactive B lymphocytes by cross-linking B-cell surface immunoglobulin receptors with the inhibitory IgG FcγRIIb receptors. Treatment with DNA-like chimeric molecules inhibited B- and T-cell proliferation, restricted the number of anti-DNA antibody-producing cells and suppressed the generation of IgG anti-DNA antibodies. In contrast, phosphate buffered saline (PBS)-injected control mice experienced an increase of disease-associated antibody levels and developed glomerulonephritis similar to pristane-treated donor Balb/c mice.
Foreign Investors and Global Integration of Emerging Indian Equity Market
Authors: Poshakwale Sunil S. , Thapa Chandra
Published: June 2010

This article examines the influence of foreign investors in explaining short-run dynamics and long-run relationship of the emerging Indian equity market with global equity markets. Using daily return series and equity portfolio investments made by foreign institutional investors, we conclude that the rapid growth in the flow of foreign equity portfolio investments is leading to greater integration of the Indian equity market with global markets. With the increased global integration, the Indian market will become more susceptible to global shocks as has been witnessed by significant losses suffered by investors in the Indian market following the sub-prime crisis.
Design of a Linear Ultrasonic Piezoelectric Motor
Authors: Sharp Scott L. , Paine Jeffery S.N. , Blotter Jonathan D.
Published: June 2010

A new geometrically unique ultrasonic motor (USM) was designed, prototyped, and tested. USMs operate by vibrating a drive tip in an elliptical motion while in periodic contact with a driven surface. Piezoelectric elements are used to create the elliptical motions and are driven at near resonance frequencies to create the needed displacements for the motor to operate. The motor in this article consists of an arched frame, a center ground, and two piezoelectric elements connected to the center ground. Several finite element models were developed to design the motor and to predict performance. The models predicted a linear motor capable of pushing up to 5 N and a maximum speed of 0.4 m/s. A prototype frame was built out of tool steel and run against an oxide ceramic plate. The prototype motor achieved a maximum speed of 55.6 mm/s and a push force of 0.348 N at a preload of 6 N. The prototype frame’s steady-state displacements were approximately 20% of the expected output from the finite element models. Reasons for these discrepancies are discussed and investigated.
Doing Case Study: Abduction Not Induction, Phronesis Not Theory
Authors: Thomas Gary
Published: June 2010

Distinctions between abduction and induction, and between phronesis and theory, are often elided in methodological discussion about case study. Making these distinctions clear offers a pathway for the better conduct of case study and for a less apologetic stance in its use. Owing its legitimacy to the experiential knowledge of phronesis rather than the generalizing power of induction and theory in explanation and prediction, case study can more unselfconsciously look to the anatomy of narrative for the justification of its processes and its conclusions. A look at this anatomy reveals a number of ways in which the valency of case study may be constructed.
Toward a model of outdoor lighting scene brightness
Authors: Rea MS , Radetsky LC , Bullough JD
Published: June 2010

Light quantities based on the photopic luminous efficiency function do not predict brightness perceptions of lighted outdoor scenes such as streets, parking lots and plazas. This paper summarises a series of experiments conducted using scale-model outdoor scenes illuminated by different light sources to assess judgements of brightness. From the results and from previously published literature on the relative increase in short-wavelength spectral sensitivity for brightness, a tentative model for brightness perception of outdoor scenes is proposed. The model can serve as a starting point for efficiently testing future hypotheses regarding brightness perception in lighted outdoor scenes.
Novel Use of Doxycycline in Continuous-Instillation Negative Pressure Wound Therapy as "Wound Chemotherapy"
Authors: Scimeca Christy L. , Bharara Manish , Fisher Timothy K. , Giovinco Nicholas , Armstrong David G.
Published: June 2010

Negative-pressure wound therapy (NPWT) is frequently employed in the treatment of complex wounds. The authors present a description of real-time streaming therapy of a variety of wound chemotherapeutic agents through NPWT. Doxycycline, which acts as a competitive inhibitor of matrix metalloproteinases and tumor necrosis factor alpha and further decreases inflammation through the reduction of nitrous oxide production, may prove helpful when delivered in this manner. To the authors’ knowledge, this is the first report in the literature describing this method of delivery of doxycycline.
Review: Developing therapies for the metabolic syndrome: challenges, opportunities, and. . . the unknown
Authors: Matfin Glenn
Published: June 2010

Metabolic syndrome refers to a clustering of established and emerging cardiovascular disease risk factors within a single individual. The established risk factors, such as obesity, diabetes, dyslipidaemia and hypertension, and other emerging risk factors are closely related to central obesity (especially intra-abdominal adiposity) and insulin resistance. However, debate continues about the very existence of the metabolic syndrome. Despite the controversies, many existing and new therapies are targeting the metabolic syndrome and component risk factors. To date, no therapies have been approved specifically for treating the metabolic syndrome. In this article some of the challenges and opportunities in developing therapies for the metabolic syndrome are discussed.
Microstructure formation and properties of HVOF sprayed NiTi coatings prepared from amorphous/nanocrystalline NiTi powders
Authors: Verdian M. M. , Salehi M. , Raeissi K.
Published: June 2010

NiTi alloys were sprayed on AISI 1045 steel substrate using high velocity oxyfuel process. In this regard, amorphous/nanocrystalline NiTi powders were used as feedstock. The phase composition and microstructure of the coatings were examined by X-ray diffraction and scanning electron microscopy. The results indicated that B2-NiTi (austenite phase), Ni4Ti3, Ni and NiTiO3 were present in the coatings. In addition, all sprayed coatings showed high microhardness values (>588 HV0·3). Further investigations showed that with the increase in fuel/oxygen ratio, the oxide content increased and porosity level decreased. Hereon, a dense coating with porosity level of 0·8% and oxide content of 5% was obtained as the optimum coating. Polarisation tests were employed to study the corrosion behaviour of the optimum coating in 3·5%NaCl solution. These tests indicated that the corrosion current density of the optimum coating is comparable to that of NiTi alloys reported in the literature.
Reactive composite brazing of Cf/SiC composites to Ti alloy with (Ag–6Al)+Ti+C composite filler materials
Authors: Wang Z. P. , Huang J. H. , Zhang H. , Zhao X. K.
Published: June 2010

Cf/SiC composite and Ti alloy (TC4) were successfully joined by the mixed powders of Ag, Al, Ti and short carbon fibres under vacuum condition. The Microstructure of the joints was investigated by X-ray diffraction, scanning electron microscopy and energy dispersive spectrometry. The results show that the good chemical bonding and reactive composite brazing joints are obtained by reactive composite brazing with both (Ag–6Al)+Ti and (Ag–6Al)+Ti+C filler materials. The addition of short carbon fibres contributes a lot to the shear strength by alleviating the thermal stress of the joints and to the in situ synthesised TiC which surround the uniformly distributed short carbon fibres. Ti element can improve filler metal's wettability to Cf/SiC composite and restrain the oxidation of Al element. The max shear strength obtained is 90·8 MPa and the optimal parameter is brazing at 910°C within 10 min.
Partitioning of trace elements between garnet, clinopyroxene and diamond-forming carbonate-silicate melt at 7 GPa
Authors: Kuzyura A. V. , Wall F. , Jeffries T. , Litvin Yu. A.
Published: June 2010

Concentrations of trace elements in coexisting garnet, clinopyroxene and completely miscible carbonate-silicate melt (formed at 7 GPa from the Chagatai silicocarbonatite rock known to be diamondiferous) were determined using LA-ICP-MS. The partition coefficients for Li, Rb, Cs, Ba, Th, U, Ta, Nb, La, Ce, Pb, Pr, Sr, Nd, Zr, Hf, Sm, Eu, Gd, Tb, Dy, Y, Ho, Er, Tm, Yb, Lu, Sc and Zn were determined. The new experimental data for trace-element partitioning between garnet, clinopyroxene and carbonate-silicate melt have been compared with published data for partitioning between garnet, clinopyroxene and carbonatite melt, and garnet, clinopyroxene and silicate melt. The results show that the trace-element partitioning is not significantly altered by changes in melt composition, with HREE always concentrated in the garnet. Carbonate-silicate melt, as a diamond-forming medium, and carbonatite or silicate melt equilibrated with mantle silicate minerals, behave similarly in respect of trace-element distribution.
Arisite-(La), a new REE-fluorcarbonate mineral from the Aris phonolite (Namibia), with descriptions of the crystal structures of arisite-(La) and arisite-(Ce)
Authors: Piilonen P. C. , McDonald A. M. , Grice J. D. , Cooper M. A. , Kolitsch U. , Rowe R. , Gault R. A. , Poirier G.
Published: June 2010

Arisite-(La), ideally NaLa2(CO3)2[F2x(CO3)1–x]F, is a new layered REE-fluorcarbonate mineral from miarolitic cavities within the Aris phonolite, Namibia (IMA no. 2009-019). It occurs as distinct chemical zones mixed with its Ce-analogue, arisite-(Ce). Crystals are vitreous, transparent beige, beige-yellow, light lemon-yellow to pinkish, and occur as tabular prisms up to 1.5 mm. Arisite-(La) is brittle, has conchoidal fracture, poor cleavage perpendicular to (001), a Mohs hardness of ~3–3½, is not fluorescent in either long- or shortwave UV radiation, dissolves slowly in dilute HCl at room temperature and sinks in methylene iodide, Dcalc. = 4.072 g cm–3. Arisite-(La) is uniaxial negative, has sharp extinction, with both ω and ε exhibiting a range of values within each grain: ω = 1.696–1.717(4) and ε = 1.594–1.611(3), a result of chemical zoning attributed to both Ce ⇌ La and Na ⇌ Ca substitutions. The crystal structure of both arisite-(Ce) and arisite-(La) were solved by direct methods and refined to R = 1.66%, wR2 = 4.31% (Ce) and R = 2.09%, wR2 = 5.26% (La), respectively. Arisite is hexagonal, Pm2, Z = 1, with unit-cell parameters of a = 5.1109(2) Å, c = 8.6713(4) Å, V = 196.16(6) Å3 for arisite-(Ce), and a = 5.1131(7) Å, c = 8.6759(17) Å, V = 196.43(5) Å3 for arisite-(La). Arisite-(Ce) and arisite-(La) are members of the layered, flat-lying REE-fluorcarbonate group which have crystal structures characterized by separate layers of triangular planar groups that parallel the overall layering of the structure, F, REE and alkali or alkaline-earthelements. Overall, the arisite structure can be defined by three distinct layers which parallel (001): (1) ∞[REE(CO3)2F] slabs, (2) sheets of Naϕ9 polyhedra, and (3) ∞[2F/CO3]2–. Based on its (M+F)/C ratio, arisite can further be described as having a dense, flat-lying fluorcarbonate structure, a classification which includes the structurally related mineral species cordylite, kukharenkoite, cebaite, lukechangite, huanghoite, and one incompletely characterized synthetic phase, NaY2(CO3)3F.
Distribution of gallium between phenocrysts and melt in peralkaline salic volcanic rocks, Kenya Rift Valley
Authors: Macdonald R. , Rogers N. W. , Bagiński B. , Dzierżanowski P.
Published: June 2010

Gallium abundances, determined by laser ablation-inductively coupled plasma-mass spectrometry, are presented for phenocrysts and glassy matrices from a metaluminous trachyte and five peralkaline rhyolites from the Greater Olkaria Volcanic Complex, Kenya Rift Valley. Abundances in the glasses range from 28.9 to 33.3 ppm, comparable with peralkaline rhyolites elsewhere. Phenocryst Ga abundances (in ppm) are: sanidine 31.5–45.3; fayalite 0.02–0.22; hedenbergite 3.3–6.3; amphibole 12; biotite 72; ilmenite 0.56–0.72; titanomagnetite 32; chevkinite-(Ce) 364. The mafic phases and chevkinite-(Ce) are enriched in Ga relative to Al, whereas Ga/Al ratios in sanidine are smaller than in coexisting glass. Apparent partition coefficients range from <0.01 in fayalite to 12 in chevkinite-(Ce). Coefficients for hedenbergite, ilmenite and titanomagnetite decrease as melts become peralkaline. The sharp increase in Ga/Al in the more fractionated members of alkaline magmatic suites probably results from alkali feldspar-dominated fractionation. Case studies are presented to show that the Ga/Al ratio may be a sensitive indicator of such petrogenetic processes as magma mixing, interaction of melts with F-rich volatile phases, mineral accumulation and volatile-induced crustal anatexis.
Tracing the origins and signatures of selection of antifolate resistance in island populations of Plasmodium falciparum
Authors: Salgueiro Patrícia , Vicente José L , Ferreira Conceição , Teófilo Vânia , Galvão André , do Rosário Virgílio E , Cravo Pedro , Pinto João
Published: June 2010

Background

Resistance of the malaria parasite Plasmodium falciparum to sulfadoxine-pyrimethamine (SP) has evolved worldwide. In the archipelago of São Tomé and Principe (STP), West Africa, although SP resistance is highly prevalent the drug is still in use in particular circumstances. To address the evolutionary origins of SP resistance in these islands, we genotyped point mutations at P. falciparum dhfr and dhps genes and analysed microsatellites flanking those genes.

Methods

Blood samples were collected in July and December 2004 in three localities of São Tomé Island and one in Principe Island. Species-specific nested-PCR was used to identify P. falciparum infected samples. Subsequently, SNPs at the dhfr and dhps genes were identified through PCR-RFLP. Isolates were also analysed for three microsatellite loci flanking the dhfr gene, three loci flanking dhps and four loci located at putative neutral genomic regions.

Results

An increase of resistance-associated mutations at dhfr and dhps was observed, in particular for the dhfr/dhps quintuple mutant, associated with clinical SP failure. Analysis of flanking microsatellites suggests multiple independent introductions for dhfr and dhps mutant haplotypes, possibly from West Africa. A reduced genetic diversity and increased differentiation at flanking microsatellites when compared to neutral loci is consistent with a selective sweep for resistant alleles at both loci.

Conclusions

This study provides additional evidence for the crucial role of gene flow and drug selective pressures in the rapid spread of SP resistance in P. falciparum populations, from only a few mutation events giving rise to resistance-associated mutants. It also highlights the importance of human migration in the spread of drug resistant malaria parasites, as the distance between the islands and mainland is not consistent with mosquito-mediated parasite dispersal.
Two heterologously expressed Planobispora rosea proteins cooperatively induce Streptomyces lividans thiostrepton uptake and storage from the extracellular medium
Authors: Giardina Anna , Alduina Rosa , Gottardi Elvira , Di Caro Valentina , Süssmuth Roderich D , Puglia Anna M
Published: June 2010

Background

A bacterial artificial chromosomal library of Planobispora rosea, a genetically intractable actinomycete strain, was constructed using Escherichia coli-Streptomyces artificial chromosome (ESAC) and screened for the presence of genes known to be involved in the biosynthesis of antibiotics.

Results

One clone with a 40 kb insert showed antimicrobial activity against Gram positive bacteria. Insert sequence analysis and subcloning experiments revealed that the bioactivity was due to a 3.5 kb DNA fragment containing two open reading frames. These orfs encode two proteins with high similarity to a putative membrane protein of Streptomyces coelicolor and to the nogalamycin resistance protein SnorO of Streptomyces nogalater, respectively. The role of these two Orfs is unknown in Planobispora. Disruption and complementation experiments revealed that both proteins are necessary for the antibacterial activity and chemical analysis demonstrated that the antibiotic activity was due to thiostrepton, antibiotic used as recombinant clone selection marker.

Conclusion

Two Planobispora rosea orfs are responsible for increasing intracellular amounts and storage of thiostrepton in Streptomyces lividans.
Naturally occurring nanoparticles from English ivy: an alternative to metal-based nanoparticles for UV protection
Authors: Xia Lijin , Lenaghan Scott C , Zhang Mingjun , Zhang Zhili , Li Quanshui
Published: June 2010

Background

Over the last decade safety concerns have arisen about the use of metal-based nanoparticles in the cosmetics field. Metal-based nanoparticles have been linked to both environmental and animal toxicity in a variety of studies. Perhaps the greatest concern involves the large amounts of TiO2 nanoparticles that are used in commercial sunscreens. As an alternative to using these potentially hazardous metal-based nanoparticles, we have isolated organic nanoparticles from English ivy (Hedera helix). In this study, ivy nanoparticles were evaluated for their potential use in sunscreens based on four criteria: 1) ability to absorb and scatter ultraviolet light, 2) toxicity to mammalian cells, 3) biodegradability, and 4) potential for diffusion through skin.

Results

Purified ivy nanoparticles were first tested for their UV protective effects using a standard spectrophotometric assay. Next the cell toxicity of the ivy nanoparticles was compared to TiO2 nanoparticles using HeLa cells. The biodegradability of these nanoparticles was also determined through several digestion techniques. Finally, a mathematical model was developed to determine the potential for ivy nanoparticles to penetrate through human skin. The results indicated that the ivy nanoparticles were more efficient in blocking UV light, less toxic to mammalian cells, easily biodegradable, and had a limited potential to penetrate through human skin. When compared to TiO2 nanoparticles, the ivy nanoparticles showed decreased cell toxicity, and were easily degradable, indicating that they provided a safer alternative to these nanoparticles.

Conclusions

With the data collected from this study, we have demonstrated the great potential of ivy nanoparticles as a sunscreen protective agent, and their increased safety over commonly used metal oxide nanoparticles.
CyberKnife® enhanced conventionally fractionated chemoradiation for high grade glioma in close proximity to critical structures
Authors: Oermann Eric , Collins Brian T , Erickson Kelly T , Yu Xia , Lei Sue , Suy Simeng , Hanscom Heather N , Kim Joy , Park Hyeon U , Eldabh Andrew , Kalhorn Christopher , McGrail Kevin , Subramaniam Deepa , Jean Walter C , Collins Sean P
Published: June 2010

Introduction

With conventional radiation technique alone, it is difficult to deliver radical treatment (≥ 60 Gy) to gliomas that are close to critical structures without incurring the risk of late radiation induced complications. Temozolomide-related improvements in high-grade glioma survival have placed a higher premium on optimal radiation therapy delivery. We investigated the safety and efficacy of utilizing highly conformal and precise CyberKnife radiotherapy to enhance conventional radiotherapy in the treatment of high grade glioma.

Methods

Between January 2002 and January 2009, 24 patients with good performance status and high-grade gliomas in close proximity to critical structures (i.e. eyes, optic nerves, optic chiasm and brainstem) were treated with the CyberKnife. All patients received conventional radiation therapy following tumor resection, with a median dose of 50 Gy (range: 40 - 50.4 Gy). Subsequently, an additional dose of 10 Gy was delivered in 5 successive 2 Gy daily fractions utilizing the CyberKnife® image-guided radiosurgical system. The majority of patients (88%) received concurrent and/or adjuvant Temozolmide.

Results

During CyberKnife treatments, the mean number of radiation beams utilized was 173 and the mean number of verification images was 58. Among the 24 patients, the mean clinical treatment volume was 174 cc, the mean prescription isodose line was 73% and the mean percent target coverage was 94%. At a median follow-up of 23 months for the glioblastoma multiforme cohort, the median survival was 18 months and the two-year survival rate was 37%. At a median follow-up of 63 months for the anaplastic glioma cohort, the median survival has not been reached and the 4-year survival rate was 71%. There have been no severe late complications referable to this radiation regimen in these patients.

Conclusion

We utilized fractionated CyberKnife radiotherapy as an adjunct to conventional radiation to improve the targeting accuracy of high-grade glioma radiation treatment. This technique was safe, effective and allowed for optimal dose-delivery in our patients. The value of image-guided radiation therapy for the treatment of high-grade gliomas deserves further study.
Obesity affects the chondrocyte responsiveness to leptin in patients with osteoarthritis
Authors: Pallu Stéphane , Francin Pierre-Jean , Guillaume Cécile , Gegout-Pottie Pascale , Netter Patrick , Mainard Didier , Terlain Bernard , Presle Nathalie
Published: June 2010

Introduction

Increasing evidence support the regulatory role of leptin in osteoarthritis (OA). As high circulating concentrations of leptin disrupt the physiological function of the adipokine in obese individuals, the current study has been undertaken to determine whether the elevated levels of leptin found in the joint from obese OA patients also induce changes in the chondrocyte response to leptin.

Methods

Chondrocytes isolated from OA patients with various body mass index (BMI) were treated with 20, 100 or 500 ng/ml of leptin. The expression of cartilage-specific components (aggrecan, type 2 collagen), as well as regulatory (IGF-1, TGFβ, MMP-13, TIMP 2) or inflammatory (COX-2, iNOS, IL-1) factors was investigated by real-time PCR to evaluate chondrocyte responsiveness to leptin. Furthermore, the effect of body mass index (BMI) on leptin signalling pathways was analyzed with an enzyme-linked immunosorbent assay for STATs activation.

Results

Leptin at 20 ng/ml was unable to modulate gene expression in chondrocytes, except for MMP-13 in obese OA patients. Higher leptin levels induced the expression of IGF-1, type 2 collagen, TIMP-2 and MMP-13. However, the activity of the adipokine was shown to be critically dependent on both the concentration and the BMI of the patients with a negative association between the activation of regulated genes and BMI for 100 ng/ml of adipokine, but a positive association between chondrocyte responsiveness and BMI for the highest leptin dose. In addition, the gene encoding MMP-13 was identified as a target of leptin for chondrocytes originated from obese patients while mRNA level of TIMP-2 was increased in leptin-treated chondrocytes collected from normal or overweight patients. The adipokine at 500 ng/ml triggered signal transduction through a STAT-dependent pathway while 100 ng/ml of leptin failed to activate STAT 3 but induced STAT 1α phosphorylation in chondrocytes obtained from obese patients.

Conclusions

The current study clearly showed that characteristics of OA patients and more expecially obesity may affect the responsiveness of cultured chondrocytes to leptin. In addition, the BMI-dependent effect of leptin for the expression of TIMP-2 and MMP-13 may explain why obesity is associated with an increased risk for OA.
Cluster analysis of Euler deconvolution solutions: New filtering techniques and geologic strike determination
Authors: Ugalde Hernan , Morris William A.
Published: June 2010

Euler deconvolution often presents the problem of filtering coherent solutions from uncorrelated ones. We have applied clustering and kernel density distribution techniques to a Euler-generated data set. First a kernel density distribution algorithm filters uncorrelated Euler solutions from those consistently located near an anomalous magnetic-gravimetric source. Then a fuzzy [Formula: see text]-means clustering algorithm is applied to the filtered data set. The computation of cluster centers reduces the size of the data set considerably, yet maintains its statistical consistency. Finally, the computation of eigenvectors and eigenvalues on the cluster centers yields an estimate of the geologic strike of the anomalous sources responsible for the observed geophysical anomalies. Therefore, we can obtain an improved strike and depth estimation of the magnetic sources. Although the algorithm can filter and cluster any Euler data set, we recommend obtaining the best solutions possible before any clustering. Hence, we have used a hybrid 3D extended Euler and 3D Werner deconvolution algorithm. We have developed synthetic and real examples from the Bathurst Mining Camp (New Brunswick, Canada). The output of this algorithm can be used as an input to any 3D geologic-modeling package.
Mission plan under uncertainty for an autonomous aircraft
Authors: Bestaoui Y
Published: June 2010

In this article, a path planning system is presented, which enables the vehicle to move in a non-predefined way. Taking into account the situation detected by the sensors and on the basis of a spatial–temporal criterion, the proposed system is able to decide whether a new reference trajectory must be planned. If an update is necessary, the reference is computed taking into account the measured states (the three-dimensional (3D) positions, the flight path and heading angles, as well as the velocity), the limitations on curvature and torsion, and the next way-point that could be the final destination. As the simple geometric path planning procedure presented in this article can be implemented in real time, updated paths can easily be generated to accommodate a slowly drifting wind direction and/or wind speed.
Experimental airborne NH∞ vision-based simultaneous localization and mapping in unknown environments
Authors: Nemra A , Aouf N
Published: June 2010

This article aims to present a robust airborne three-dimensional (3D) visual simultaneous localization and mapping (VSLAM) solution based on a stereovision system embedded in a remotely piloted helicopter. The proposed solution enables an unmanned aerial vehicle to construct a reliable map and localize itself in this map without any user intervention. The main contributions of this article are threefold: first, based on an adaptive scale-invariant feature transform algorithm, a robust approach for feature extraction and matching is proposed. Second, an adaptation of the non-linear H∞ filtering scheme is presented to the VSLAM problem, for which a 3D vision-based observation model is suggested. This filtering scheme avoids issues linked with the classical extended Kalman filtering techniques such as linearization errors, initialization problems, and noise statistics assumptions. Finally, a reliable map management approach, based on the k-nearest landmark concept, is presented to allow efficient loop closing detection and map building. This approach reduces significantly the complexity of the airborne VSLAM algorithm by making it independent of the landmark number. Experimental results using real data sets show the performance and the robustness of the proposed airborne VSLAM solution to build a reliable map and localize the unmanned aerial vehicle within this map.
Determining the optimal testing parameters on the abrasive wear behaviour of FeCr-reinforced iron-based composites
Authors: Ay M , Çaydaş U , Hasçalik A
Published: June 2010

This article presents an experimental study of abrasive wear characteristics of FeCr-reinforced iron-based composites produced by the powder metallurgy technique. The wear process parameters are optimized for minimum weight loss based on L9 Taguchi orthogonal design with three wear parameters, namely the FeCr reinforcement ratio, particulate size, and applied loads. Wear tests were carried out using a pin-on-disc type of apparatus. The orthogonal array, signal-to-noise ratio, and analysis of variance are employed to investigate the optimal testing parameters. The experimental results demonstrate that the applied load was the major parameter among the controllable factors that influence the weight loss of composites. The microstructures and compositions of produced composites are also studied with the help of scanning electron microscopy, light optical microscopy, energy dispersive spectrograph, and X-ray diffraction analysis. Finally, the optimal combination of the testing parameters was determined. A good agreement between the predicted and actual weight loss was observed within±5 per cent.
Presentation of a new method to measure the friction coefficient using an electromagnetic digital device
Authors: Petit L , Bigerelle M , Jourani A , Dore E , Prelle C , Lamarque F
Published: June 2010

In this article, a new method to measure the friction coefficient based on an electromagnetic digital device is presented. First of all, the principle and a modelling of this device are detailed. Using this modelling, an experimental prototype has been designed, manufactured, and tested. Next, the principle of the micro-tribometer based on this one is described. Finally, the method to determine the friction coefficient value from experimental measurements is presented, and the sensitivity of the micro-tribometer is studied.
Friction and wear analysis of a cement kiln dust- reinforced epoxy-based functionally graded materials
Authors: Siddhartha V , Patnaik A , Bhatt A D
Published: June 2010

The wear behaviour of new material epoxy matrix homogeneous composites and its functionally graded materials reinforced with uniform-sized cement kiln dust (CKD) is discussed in this article. The tribological behaviour of CKD particulate-reinforced homogeneous and graded epoxy composites synthesized by simple mechanical stirring and vertical centrifugal casting techniques, respectively, is investigated. Mechanical properties of graded and homogeneous composites are evaluated and compared. Sliding wear tests are performed over a range of sliding velocities (105–314 cm/s), normal loads (20–40 N), filler contents (0–20 wt%), and sliding distances (0.5–2 km) using a pin-on-disc machine. A statistics-based design of experiments approach using Taguchi's orthogonal arrays is used. This study establishes that the presence of CKD particles enhances the sliding wear resistance of graded composites. Out of all synthesized composites 10 wt% graded composite exhibits the maximum impact strength which clearly indicates that the effect of the fabrication technique is much more pronounced for impact strength. Scanning electron microscope (SEM) and optical microstructures confirm the continuous graded dispersion of CKD particles in the matrix.