bluuebunny/crossref_metadata_2025 huggingface dataset:
U–Pb geochronology of the Mazinaw terrane, an imbricate segment of the Central Metasedimentary Belt, Grenville Province, Ontario
Authors: Corfu Fernando , Easton R. Michael
Published: January 2011

The Mazinaw terrane, in the Central Metasedimentary Belt of the Grenville Province comprises, volcanic, sedimentary, and plutonic rocks that were intensely folded and faulted, and metamorphosed to as high as upper amphibolite facies. U–Pb geochronology establishes an early period of magmatism and sedimentation at about 1280–1240 Ma, probably in a marginal basin setting, and a multistage rhetamorphic evolution in the period between 1100 and 980 Ma, which was probably related to crustal thickening by imbrication during compression and wedging of the terrane. Some of the earliest magmatism formed calc-alkalic volcanic rocks of Kashwakamak Formation at 1276 ± 2 Ma. An associated sedimentary assemblage was intruded by the Helena trondhjemite stock at 1267 ± 5 Ma. A younger succession, formed between 1250 and 1240 Ma, includes the bimodal volcanic Mazinaw Lake Formation, alaskitic granites of the Norway Lake and Abinger plutons, and a granodioritic gneiss phase of the Cross Lake pluton. These units were covered unconformably by the Flinton Group sometime after 1150 Ma, as defined by published detrital zircon data. A northern segment of the Mazinaw terrane underwent deformation and metamorphism accompanied by the emplacement of granitic pegmatites in the period between 1100 and 1050 Ma. In contrast, metamorphism and deformation occurred significantly later in central domains, as shown by several metamorphic zircon populations grown at about 1040–1030, 1020, and 1010–1000 Ma, by pegmatite emplacement at about 980 Ma, and titanite ages of 1010–960 Ma. Younger rutile ages of about 915 Ma may reflect uplift of the terrane. Some rutile also appears to record the latest Proterozoic faulting and mafic diking related to formation of the Ottawa-Bonnechere graben at about 600 Ma.
Multiple origins for mantle harzburgites: examples from the Lewis Hills, Bay of Islands ophiolite, Newfoundland
Authors: Edwards Stephen J. , Malpas John
Published: January 2011

Harzburgite is a common rock type in ophiolites and alpine peridotites. It is considered to be typical of a residual mantle mineralogy, i.e., material left behind after periods of extensive mantle melting and melt–rock and fluid–rock interactions that produce a variety of basaltic melts. The processes by which these melts and residua are produced are complicated; therefore, to fully understand them, it is necessary to undertake detailed and integrated field, petrographic, and geochemical studies of large exposures of mantle material as part of the investigative process. Such a study in the Bay of Islands ophiolite exposed in the Lewis Hills of Newfoundland has enabled the identification of four major types of harzburgite, which represent examples of a complete spectrum of this rock type. Depleted, residual harzburgite and associated dunite, with positive-sloping rare earth element patterns, may develop U-shaped rare earth element patterns and a visible orthopyroxene enrichment by the introduction of a component of high-Mg, quartz-normative melt, or a hydrous fluid component with a high Si/Al ratio. Conversely, U-shaped rare earth element patterns and apparent orthopyroxene depletion may occur by the addition of low-Si/Al, hydrous fluid. Such enrichments and depletions of orthopyroxene by solution–precipitation reactions may result not only in the variety of harzburgite types, which on partial melting might produce a range of melt products, but also in fronts of harzburgite migrating through the mantle.
Le volcanisme quaternaire d'Anatolie centrale (Turquie): association de magmatismes calco-alcalin et alcalin en domaine de convergence
Authors: Aydar E. , Gourgaud A. , Deniel C. , Lyberis N. , Gundogdu N.
Published: January 2011

Collision volcanism in Central Anatolia (Cappadocia) began at least in the late Miocene. Because of the North–South Arabian-Eurasian convergence since this period, the Anatolian block is displaced towards the West along the North and East Anatolian strike-slip faults. Kinematic reconstructions show that the East Anatolian Fault is both sinistral and convergent. As a consequence, the Anatolian block is currently being deformed. Quaternary volcanism in Central Anatolia is represented by several hundreds of monogenetic scoria cones, lava flows, maars, and domes as well as two strato-volcanoes, Hasan Dag and Erciyes Dag. The monogenetic volcanism is bimodal (basalts and rhyolites), whereas the stratovolcanoes exhibit a complete calc-alkaline suite, from basalts to rhyolites. Most of the igneous products are calc-alkaline. Basalts erupted mainly from the monogenetic cones, lava flows, and maars. Andesites are encountered in the strato-volcanoes as lava flows, domes, and nuees ardentes deposits. Dacites and rhyolites occur as ignimbrites and dispersed maars and domes. Volcanic events were recorded up to historical times. Some basalts from monogenetic edifices, contemporaneous with the calc-alkaline suite, exhibit mineralogical and geochemical features that are typical of intraplate alkaline suites, such as normative nepheline, alkali feldspars, and Ti and Cr-rich Cpx. Euhedral microlites of aluminous garnet, although rare, have been observed in basalts, rhyodacites, and rhyolites. This association of contemporaneous calc-alkaline and alkaline suites may be related to collision tectonics.
Syn- and postrift evolution of the El Jadida – Agadir basin (Morocco): constraints for the rifting models of the central Atlantic
Authors: Medina Fida
Published: January 2011

The El Jadida – Agadir basin shows an evolution related to that of the central Atlantic rifting history. The synrift period (late Early Triassic to earliest Jurassic) is dominated by deposition of red clastic sediments and evaporites, which are overlain by or intercalated with basalt flows. Two intense extensional phases are recognized. The first, probably in Middle Triassic times, is oriented north-northwest–south-southeast and resulted in the formation of east-northeast–west-southwest-oriented grabens and half-grabens. The second, a widespread northwest–southeast-trending extension, is Ladinian to earliest Liassic, and induced the formation of westward-dipping half-grabens. Extensional tectonics initiated in the southern part of the basin and migrated northwards, contrary to classical ideas proposing rifting from north to south. The postrift evolution is characterized by Jurassic to Eocene subsidence. Tectonism appears to have been restricted to a narrow area close to the present-day coast. Subsidence history shows four stages of rapid subsidence disrupting the thermal-relaxation period. The values of extension are moderate, ranging from 1.1 to 1.34. The best model that accounts for this evolution is the one combining simple shear at the onset of rifting and pure shear by its end.
A 12 000 year radiocarbon date of deglaciation from the Continental Divide of northwestern Montana
Authors: Carrara Paul E.
Published: January 2011

During the Pinedale (Late Wisconsinan) glaciation, an outlet glacier from a mountain ice field flowed eastward across the Continental Divide through Marias Pass in northwestern Montana. This outlet glacier was the major source of the Two Medicine glacier, a large piedmont glacier that extended from the mountain front east about 55 km onto the plains. An accelerator mass spectrometry radiocarbon age of 12 194 ± 145 BP (AA-9530) was obtained from a wood fragment, underlying a Glacier Peak tephra and a Mount Saint Helens set J tephra in a section of lake sediments, near Marias Pass. This radiocarbon age provides a minimum date of deglaciation for the Marias Pass area that is about 800 years older than a previous estimate. Furthermore, the radiocarbon age indicates that the Two Medicine glacier was no longer being supplied by its major source and if it still existed was only as a dying, stagnant ice mass.
The postglacial relative sea-level lowstand in Newfoundland
Authors: Shaw John , Forbes Donald L.
Published: January 2011

Relative sea level in coastal regions of Newfoundland fell from late-glacial maximum levels to postglacial minima in several phases: (i) an early period of high relative sea level, when Late Wisconsinan ice was at the coast and discharging meltwater plumes into the ocean; (ii) a period of rapidly falling relative sea level, during which glaciers retreated inland; and (iii) a period without glacier ice, during which relative sea level continued to fall, but at decreasing rates. Falling relative sea level caused fluvial incision of glacial deposits in some coastal embayments, and culminated with the construction of lowstand marine deltas. These deltas were submerged during the subsequent Holocene transgression. Seismic reflection data from selected deltas show that they comprise wedges of sediment with prograded, seaward-dipping, foreset-style internal reflections. The depth of the relative sea-level lowstand varies spatially, and it was diachronous. It occurred relatively early and deep in peripheral regions (i.e., farther from the centre of the island), but was later and shallower landward, and close to its northern limits. Approximate ages of the lowstand are 9.5 ± 1 ka in the St. George's Bay – Port au Port region, just over 8.6 ka in Hamilton Sound, before 7.0 ka at Swift Current, 8.7 ka at Connoire Bay, just over 8.2 ka in Bay d'Espoir, and ca. 6.5 ka on the Great Northern Peninsula. The relative sea-level minima range down to at least –30 m, and form a concentric pattern around central Newfoundland, similar to the pattern of raised marine limits.
A new tetradiid coral from the Late Ordovician of Manitoba
Authors: Young Graham A.
Published: January 2011

Tetradiids are common Ordovician fossils in many parts of the world. Their occurrence in the western interior of North America has been noted, but they have never previously been described from this region. Rhabdotetradium garsonense n.sp. occurs in the Selkirk Member of the Red River Formation at Garson, Manitoba (Late Ordovician, Maysvillian). This species is characterized by small corallites with diameters commonly 0.6–1.1 mm; in transverse sections these are separated from one another or occur in clumps or chains. The variability of corallite arrangement within single coralla of this species illustrates the difficulty of discriminating tetradiid genera. The diagnosis of Rhabdotetradium is revised to more clearly delineate the boundary between it and Paratetradium, which has corallites arranged contiguously in elongate chains.
Mesozoic and Cenozoic stratigraphy, eastern Scotian Shelf: new interpretations
Authors: Wade J. A. , Williams G. L. , MacLean B. C.
Published: January 2011

A 320 km long, deep seismic reflection line across the central part of the Scotian Basin provides new insight on the deep stratigraphy of the basin, confirms the existence of up to 18 km of Mesozoic and Cenozoic sedimentary strata, and provides additional control on the relationship of proximal and distal stratigraphic units within the basin. Detailed biostratigraphic and seismic correlation from three outer shelf–upper slope wells yields important new information on Late Cretaceous and Tertiary unconformities and identifies a number of third-order sequence boundaries. The dating of prominent unconformities and correlation with the oceanic seismic markers ACand AUresults in the reidentification of these horizons in the Sohm Abyssal Plain.
ON THE STABILITY OF SELF-PROPELLED BODIES WITH RESPECT TO THEIR SHAPE MOTION
Authors: BONNIVARD MATTHIEU
Published: January 2011

This paper studies the stability of the trajectories of self-propelled bodies immersed in a fluid at low Reynolds number, with respect to their dynamic shape deformation. We consider both adherence and perfect slip boundary conditions on the moving body. Using shape derivative arguments in association with recent higher order regularity results for the Bogovskiĭ operator, we bring the shape stability question to a finite dimension dynamical system analysis.
SPECTROSCOPIC STUDY OF PROPOFOL BINDING TO HUMAN SERUM ALBUMIN
Authors: DARWISH SAQER M.
Published: January 2011

The interaction of propofol and human serum albumin (HSA) has been investigated by UV-absorption, fluorescence spectroscopy and Fourier transform infrared (FT-IR) spectroscopy. Propofol has shown a strong ability to quench the intrinsic fluorescence of HSA through a static quenching procedure. The binding constant (k) is estimated at a low value of 2.55 × 103M-1at 293 K. FT-IR spectroscopy with Fourier self-deconvolution technique was used to determine the protein secondary structure in the amide regions I, II and III. The observed spectral changes of HSA-propofol complex indicate a larger intensity decrease in the absorption band of α-helix relative to that of β-sheets. This variation in intensity is related indirectly to the formation of H-bonding in the complex molecules, which accounts for the different intrinsic propensities of α-helix and β-sheets.
CHEMOMECHANICAL COUPLING AND STOCHASTIC THERMODYNAMICS OF THEF1-ATPase MOLECULAR MOTOR WITH AN APPLIED EXTERNAL TORQUE
Authors: GERRITSMA E. , GASPARD P.
Published: January 2011

The effects of external torque on the F1-ATPase rotary molecular motor are studied from the viewpoint of recent advances in stochastic thermodynamics. This motor is modeled in terms of discrete-state and continuous-state stochastic processes. The dependence of the discrete-state description on external torque and friction is obtained by fitting its transition rates to a continuous-angle model based on Newtonian mechanics with Langevin fluctuating forces and reproducing experimental data on this motor. In this approach, the continuous-angle model is coarse-grained into discrete states separated by both mechanical and chemical transitions. The resulting discrete-state model allows us to identify the regime of tight chemomechanical coupling of the F1motor and to infer that its chemical and mechanical efficiencies may reach values close to the thermodynamically allowed maxima near the stalling torque. We also show that, under physiological conditions, the F1motor is functioning in a highly-nonlinear-response regime, providing a rotation rate a million times faster than would be possible in the linear-response regime of nonequilibrium thermodynamics. Furthermore, the counting statistics of fluctuations can be obtained in the tight-coupling regime thanks to the discrete-state stochastic process and we demonstrate that the so-called fluctuation theorem provides a useful method for measuring the thermodynamic forces driving the motor out of equilibrium.
HIV Drug Resistance-Associated Mutations in Antiretroviral Naïve HIV-1-Infected Latin American Children
Authors: Soto-Ramirez Luis E. , Rodriguez-Diaz Roberto , Harris D. Robert , Hazra Rohan
Published: January 2011

Our goal was to describe the presence of HIV drug resistance among HIV-1-infected, antiretroviral (ARV) naïve children and adolescents in Latin America and to examine resistance in these children in relation to drug exposure in the mother. Genotyping was performed on plasma samples obtained at baseline from HIV-1-infected participants in a prospective cohort study in Brazil, Argentina, and Mexico (NISDI Pediatric Study). Of 713 HIV-infected children enrolled, 69 were ARV naïve and eligible for the analysis. At enrollment, mean age was 7.3 years; 81.2% were infected with HIV perinatally. Drug resistance mutations (DRMs) were detected in 6 (8.7%; 95% confidence interval 3.1–18.2%) ARV-naïve subjects; none of the mothers of these 6 received ARVs during their pregnancies and none of the children received ARV prophylaxis. Reverse transcriptase mutations K70R and K70E were detected in 3 and 2 subjects, respectively; protease mutation I50 V was detected in 1 subject. Three of the 6 children with DRMs initiated ARV therapy during followup, with a good response in 2. The overall rate of primary drug resistance in this pediatric HIV-infected population was low, and no subjects had more than 1 DRM. Mutations associated with resistance to nucleoside reverse transcriptase inhibitors were the most prevalent.
Synthesis of Boron Nitride Nanotubes by Self‐Propagation High‐Temperature Synthesis and Annealing Method
Authors: Wang Jilin , Gu Yunle , Zhang Laiping , Zhao Guowei , Zhang Zhanhui
Published: January 2011

High‐quality boron nitride nanotubes were synthesized by annealing porous precursor in flowing NH3 gas at 1150°C. The porous precursor B18Ca2(MgO)9 was produced by self‐propagation high‐temperature synthesis (SHS) method using Mg, B2O3, and CaB6 as the starting materials, which played an important role in synthesis of BN nanotubes in large quantities. Samples were characterized by SEM, TEM, EDX, HRTEM, X‐ray powder diffraction (XRD), Raman, and Fourier transform infrared (FTIR) spectroscopy. The as‐synthesized BN nanotubes have an average diameter of about 150 nm with a wall/diameter ratio of 2/3. Mean length of the BN nanotubes was more than 10 μm. The effects of temperature, time, and the possible mechanism of the growth of the BN nanotubes were also discussed.
Archaeosome Adjuvant Overcomes Tolerance to Tumor‐Associated Melanoma Antigens Inducing Protective CD8+ T Cell Responses
Authors: Krishnan Lakshmi , Deschatelets Lise , Stark Felicity C. , Gurnani Komal , Sprott G. Dennis
Published: January 2011

Vesicles comprised of the ether glycerolipids of the archaeon Methanobrevibacter smithii (archaeosomes) are potent adjuvants for evoking CD8+ T cell responses. We therefore explored the ability of archaeosomes to overcome immunologic tolerance to self‐antigens. Priming and boosting of mice with archaeosome‐antigen evoked comparable CD8+ T cell response and tumor protection to an alternate boosting strategy utilizing live bacterial vectors for antigen delivery. Vaccination with melanoma antigenic peptides TRP181-189 and Gp10025-33 delivered in archaeosomes resulted in IFN‐γ producing antigen‐specific CD8+ T cells with strong cytolytic capability and protection against subcutaneous B16 melanoma. Targeting responses against multiple antigens afforded prolonged median survival against melanoma challenge. Entrapment of multiple peptides within the same vesicle or admixed formulations were both effective at evoking CD8+ T cells against each antigen. Melanoma‐antigen archaeosome formulations also afforded therapeutic protection against established B16 tumors when combined with depletion of T‐regulatory cells. Overall, we demonstrate that archaeosome adjuvants constitute an effective choice for formulating cancer vaccines.
Subprime Risk and Insurance with Regret
Authors: Petersen M. A. , Mukuddem-Petersen J. , Mulaudzi M. P. , de Waal B. , Schoeman I. M.
Published: January 2011

This paper investigates some of the risk and insurance issues related to the subprime mortgage crisis. The discussion takes place in a discrete‐time framework with a subprime investing bank being considered to be regret and risk averse before and during the mortgage crisis, respectively. In particular, we investigate the bank′s investment choices related to risky subprime structured mortgage products and riskless treasuries. We conclude that if the bank takes regret into account, it will be exposed to higher risk when the difference between the expected returns on subprime structured mortgage products and treasuries is small. However, there is low‐risk exposure when this difference is high. Furthermore, we assess how regret can influence the bank′s view of a rate of return guarantee from monoline insurers. We find that before the crisis, regret decreased the investment bank′s preparedness to forfeit on returns when its structured product portfolio was considered to be safe. Alternatively, risk‐ and regret‐averse banks forfeit the same returns when their structured mortgage product portfolio is considered to be risky. We illustrate the aforementioned findings about structured mortgage products and monoline insurance via appropriate examples.
Parallel High-Throughput RNA Interference Screens Identify PINK1 as a Potential Therapeutic Target for the Treatment of DNA Mismatch Repair–Deficient Cancers
Authors: Martin Sarah A. , Hewish Madeleine , Sims David , Lord Christopher J. , Ashworth Alan
Published: January 2011

Synthetic lethal approaches to cancer treatment have the potential to deliver relatively large therapeutic windows and therefore significant patient benefit. To identify potential therapeutic approaches for cancers deficient in DNA mismatch repair (MMR), we have carried out parallel high-throughput RNA interference screens using tumor cell models of MSH2- and MLH1-related MMR deficiency. We show that silencing of the PTEN-induced putative kinase 1 (PINK1), is synthetically lethal with MMR deficiency in cells with MSH2, MLH1, or MSH6 dysfunction. Inhibition of PINK1 in an MMR-deficient background results in an elevation of reactive oxygen species and the accumulation of both nuclear and mitochondrial oxidative DNA lesions, which likely limit cell viability. Therefore, PINK1 represents a potential therapeutic target for the treatment of cancers characterized by MMR deficiency caused by a range of different gene deficiencies. Cancer Res; 71(5); 1836–48. ©2011 AACR.
p38/MAPK Inhibitor Modulates the Expression of Dorsal Horn GABA(B) Receptors in the Spinal Nerve Ligation Model of Neuropathic Pain
Authors: Wu Junzhen , Xu Yongming , Pu ShaoFeng , Jiang Wei , Du Dongping
Published: January 2011

Background: Neuropathic pain is one of the most challenging clinical problems due to a lack of understanding the mechanisms. Recent studies have suggested that activated microglia in spinal cord may play a vital role in nerve injury-induced neuropathic pain, but the exact mechanisms have not been fully determined. Methods: First, we investigated the changes of dorsal horn GABA(B) receptor 1 (R1) expression in spinal nerve ligation rats. Second, we explored whether activated microglia contributed to such neuron changes by intrathecal administration of the p38 inhibitor, SB203580. Results: In this study, we found a dynamic change of GABA(B)R1a protein expression after spinal nerve ligation, and the peripheral nerve injury-induced downregulation of GABA(B)R1a expression in the spinal dorsal horn could be prevented by intrathecal administration of a p38/MAPK inhibitor SB203580. Conclusions: Our results provide valuable information for a better understanding of neuropathic pain and may contribute to developing effective treatments in future studies.
Reversal of Severe Heart Failure With a Continuous-Flow Left Ventricular Assist Device and Pharmacological Therapy
Authors: Birks Emma J. , George Robert S. , Hedger Mike , Bahrami Toufan , Wilton Penny , Bowles Christopher T. , Webb Carole , Bougard Robert , Amrani Mohammed , Yacoub Magdi H. , Dreyfus Gilles , Khaghani Asghar
Published: January 2011

Background—

We have previously shown that a specific combination of drug therapy and left ventricular assist device unloading results in significant myocardial recovery, sufficient to allow pump removal, in two thirds of patients with dilated cardiomyopathy receiving a Heartmate I pulsatile device. However, this protocol has not been used with nonpulsatile devices.

Methods and Results—

We report the results of a prospective study of 20 patients who received a combination of angiotensin-converting enzymes, β-blockers, angiotensin II inhibitors, and aldosterone antagonists followed by the β
2
-agonist clenbuterol and were regularly tested (echocardiograms, exercise tests, catheterizations) with the pump at low speed. Before left ventricular assist device insertion, patient age was 35.2±12.6 years (16 male patients), patients were on 2.0±0.9 inotropes, 7 (35) had an intra-aortic balloon pump, 2 were hemofiltered, 2 were ventilated, 3 had a prior Levitronix device, and 1 had extracorporeal membrane oxygenation. Cardiac index was 1.39±0.43 L · min
−1
· m
−2
, pulmonary capillary wedge pressure was 31.5±5.7 mm Hg, and heart failure history was 3.4±3.5 years. One patient was lost to follow-up and died after 240 days of support. Of the remaining 19 patients, 12 (63.2) were explanted after 286±97 days. Eight had symptomatic heart failure for ≤6 months and 4 for >6 months (48 to 132 months). Before explantation, at low flow for 15 minutes, ejection fraction was 70±7, left ventricular end-diastolic diameter was 48.6±5.7 mm, left ventricular end-systolic diameter was 32.3±5.7 mm, mV̇
o
2
was 21.6±4 mL · kg
−1
· min
−1
, pulmonary capillary wedge pressure was 5.9±4.6 mm Hg, and cardiac index was 3.6±0.6 L · min
−1
· m
−2
. Estimated survival without heart failure recurrence was 83.3 at 1 and 3 years. After a 430.7±337.1-day follow-up, surviving explants had an ejection fraction of 58.1±13.8, left ventricular end-diastolic diameter of 59.0±9.3 mm, left ventricular end-systolic diameter of 42.0±10.7 mm, and mV̇
o
2
of 22.6±5.3 mL · kg
−1
· min
−1
.

Conclusions—

Reversal of end-stage heart failure secondary to nonischemic cardiomyopathy can be achieved in a substantial proportion of patients with nonpulsatile flow through the use of a combination of mechanical and pharmacological therapy.
Associations Between Acute Kidney Injury and Cardiovascular and Renal Outcomes After Coronary Angiography
Authors: James Matthew T. , Ghali William A. , Knudtson Merril L. , Ravani Pietro , Tonelli Marcello , Faris Peter , Pannu Neesh , Manns Braden J. , Klarenbach Scott W. , Hemmelgarn Brenda R.
Published: January 2011

Background—

Acute kidney injury (AKI) is associated with early mortality after percutaneous coronary revascularization procedures, but its prognostic relevance to long-term clinical outcomes remains controversial.

Methods and Results—

We conducted a retrospective study of 14 782 adults who received coronary angiography in the province of Alberta, Canada, between 2004 and 2006. AKI was identified on the basis of changes in serum creatinine concentration within 7 days of the procedure according to AKI Network criteria. The associations between AKI and long-term outcomes, including mortality, end-stage renal disease, and cardiovascular and renal hospitalizations, were studied with the use of Cox regression of multiple failure times. The adjusted risk of death increased with increasing severity of AKI; compared with no AKI, the adjusted hazard ratio for death was 2.00 (95% confidence interval, 1.69 to 2.36) with stage 1 AKI and 3.72 (95% confidence interval, 2.92 to 4.76) with stage 2 or 3 AKI. The adjusted risk of end-stage renal disease requiring renal replacement therapy also increased according to the severity of AKI (hazard ratio, 4.15 [95% confidence interval, 2.32 to 7.42] and 11.74 [95% confidence interval, 6.38 to 21.59], respectively), as did the risks of subsequent hospitalizations for heart failure and acute renal failure.

Conclusions—

These findings inform the controversy surrounding AKI after angiography, demonstrating that it is a significant risk factor for long-term mortality, end-stage renal disease, and hospitalization for cardiovascular and renal events after coronary angiography.
Genetic Risk Score and Risk of Myocardial Infarction in Hispanics
Authors: Qi Lu , Ma Jiantao , Qi Qibin , Hartiala Jaana , Allayee Hooman , Campos Hannia
Published: January 2011

Background—

Genome-wide association studies have identified loci associated with coronary heart disease in whites of European ancestry. This study evaluated whether genetic markers previously identified in whites are associated with nonfatal acute myocardial infarction (MI) in Hispanics.

Methods and Results—

Cases (n=1989) with a first nonfatal acute MI and population-based controls (n=2096) living in Costa Rica were studied. Fourteen single-nucleotide polymorphisms were genotyped. Seven single-nucleotide polymorphisms at 3 independent loci showed significant associations with MI. The odds ratios for the loci with the strongest associations were 1.16 (95 confidence interval [CI], 1.05 to 1.27) for rs4977574 (
CDKN2A/2B
), 1.15 (95 CI, 1.03 to 1.29) for rs646776 (
CELSR2-PSRC1-SORT1
), and 1.22 (95 CI, 1.08 to 1.38) for rs501120 (
CXCL12
); the corresponding PARs were 6.8, 10.5, and 15.2; respectively. We developed a genetic risk score by summing the number of the top 3 associated risk alleles. The OR for MI per genetic risk score unit was 1.18 (95 CI, 1.11 to 1.25;
P
=4.83×10
−8
). Discrimination of MI was significantly improved (
P
=0.02) when the genetic risk score was added to a model including clinical predictors. However, the increase in the area under the receiver-operating characteristic curve after the genetic risk score was added was moderate, from 0.67 (95 CI, 0.65 to 0.69) to 0.68 (95 CI, 0.66 to 0.70).

Conclusions—

These results indicate both the consistency and disparity of genetic effects on risk of MI between Hispanic and white populations. The improvement in the identified genetic markers on discrimination of MI in Hispanics was modest.
Relationship Between Muscle Sympathetic Nerve Activity and Aortic Wave Reflection Characteristics in Young Men and Women
Authors: Casey Darren P. , Curry Timothy B. , Joyner Michael J. , Charkoudian Nisha , Hart Emma C.
Published: January 2011

Increased arterial stiffness is associated with higher levels of aortic wave reflection and aortic blood pressure. Recent evidence suggests a link between muscle sympathetic nerve activity and indices of arterial stiffness. Therefore, the aims of this study were to examine the relationship between resting muscle sympathetic nerve activity and characteristics of aortic pressure wave reflection and the influence of sex on these relationships. In 44 subjects (23 females and 21 males; 25±1 years of age), we measured muscle sympathetic nerve activity via peroneal microneurography. In addition, noninvasive aortic pressure waveforms were synthesized from radial pressure waveforms obtained from applanation tonometry. Aortic blood pressure, augmentation index, wave reflection amplitude, and wasted left ventricular energy were calculated. Resting sympathetic activity (bursts/100 heart beats) was not associated with any of the aortic pressure wave reflection characteristics for all patients. However, there was a positive relationship between sympathetic activity and augmentation index (
r
=0.46;
P
=0.05) in men. Further, sympathetic activity in men was related to wave reflection amplitude (
r
=0.53;
P
<0.05) and wasted left ventricular energy (
r
=0.57;
P
<0.01). In contrast to men, women demonstrated strong inverse relationships between sympathetic activity and augmentation index (
r
=−0.63), wave reflection amplitude (
r
=−0.59), and wasted left ventricular energy (
r
=−0.58;
P
<0.01 for all). Our results suggest another possible mechanism by which young women are protected against the development of cardiovascular disease.
The Effects of Continuous Positive Airway Pressure on Prehypertension and Masked Hypertension in Men With Severe Obstructive Sleep Apnea
Authors: Drager Luciano F. , Pedrosa Rodrigo P. , Diniz Patrícia M. , Diegues-Silva Luzia , Marcondes Bianca , Couto Roberta B. , Giorgi Dante M.A. , Krieger Eduardo M. , Lorenzi-Filho Geraldo
Published: January 2011

Obstructive sleep apnea and hypertension are common conditions that frequently coexist. Continuous positive airway pressure (CPAP) reduces blood pressure in patients with obstructive sleep apnea and sustained hypertension. However, the impact of CPAP on patients with obstructive sleep apnea and prehypertension and masked hypertension, conditions associated with increased cardiovascular risk, is unknown. Thirty-six male patients (age, 43±7 years; body mass index, 28.8±3.0 kg/m
2
) with untreated severe obstructive sleep apnea (apnea–hypopnea index, 56±22 events/hr on polysomnography) with diagnostic criteria for prehypertension and/or masked hypertension, based on office and 24-hour ambulatory blood pressure monitoring, respectively, were studied. The patients randomized to no treatment (control; n=18) or CPAP (n=18) for 3 months had similar frequency of prehypertension and masked hypertension at study entry. There were no significant changes in blood pressure in patients randomized to the control group. In contrast, patients randomized to CPAP presented significant reduction in office systolic (from 126±5 to 121±7 mm Hg;
P
=0.001) and a trend for diastolic blood pressure (from 75±7 to 73±8 mm Hg;
P
=0.08) as well as a significant decrease in daytime and nighttime systolic and diastolic blood pressure (
P
<0.05 for each comparison). There was a significant reduction in the frequency of prehypertension (from 94% to 55%;
P
=0.02) and masked hypertension (from 39% to 5%;
P
=0.04) only in the CPAP group. In conclusion, effective CPAP therapy promotes significant reduction in the frequency of prehypertension and masked hypertension by promoting significant blood pressure reductions in patients with severe obstructive sleep apnea.
Culture and Stereotype Communication
Authors: Yeung Victoria Wai Lan , Kashima Yoshihisa
Published: January 2011

This article presents an ecological approach to communication of stereotype-relevant information. We propose that communicating more stereotype-consistent (SC) and less stereotype-inconsistent (SI) information is a default strategy used by Easterners to fulfill their culturally installed goal—namely, to maintain harmonious relationships with others. And communicating informative information (both SC and SI information, and even more SI information) is a default strategy used by Westerners to fulfill their culturally installed goal—namely, to be accurate. When Easterners and Westerners were asked to communicate a firsthand stereotype-relevant story to a purported (Study 1) and a real (Study 2) communication partner without specifying a clear communication goal, they resorted to their cultural default strategy. However, when they were instructed to have a clear communication goal indicating the inappropriateness of the use of the default strategy, their communication pattern changed (Study 3). Results are discussed in terms of societal constraints of individualistic and collectivistic societies.
Avowing violence: Foucault and Derrida on politics, discourse and meaning
Authors: Frazer Elizabeth , Hutchings Kimberly
Published: January 2011

This article enquires into the understanding of violence, and the place of violence in the understanding of politics, in the work of Michel Foucault and Jacques Derrida. These two engaged in a dispute about the place of violence in their respective philosophical projects. The trajectories of their respective subsequent bodies of thought about power, politics and justice, and the degrees of affirmation or condemnation of the violent nature of reality, language, society and authority, can be analysed in relation to political traditions of realism, radicalism and liberalism. We trace the starting points, and points of convergence and divergence between them, and consider the implications of their work for our capacity to critically judge episodes and uses of violence in political contexts.
New Institutionalism Through a Gender Lens: Towards a Feminist Institutionalism?
Authors: Mackay Fiona , Kenny Meryl , Chappell Louise
Published: January 2011

New institutionalism (NI) may no longer qualify as being ‘new’, but since re-emphasizing institutions as a central explanatory variable in political analysis over two decades ago, it continues to provide scholars with a useful perspective through which to analyse political dynamics and outcomes that shape everyday life. The renewed focus on institutions has rebalanced the structure/agency scales back toward the former without losing important insights about the role and impact of political actors. NI has allowed for greater understanding about the co-constitutive nature of politics: the various ways in which actors bring about or resist change in institutions; and the way institutions shape the nature of actors’ behaviour through the construction of rules, norms and policies.
Beating-heart coronary artery bypass surgery with the help of mini extracorporeal circulation for very high-risk patients
Authors: Munos Emmanuel , Calderon Joachim , Pillois Xavier , Lafitte Stéphane , Ouattara Alexandre , Labrousse Louis , Roques Xavier , Barandon Laurent
Published: January 2011

Background: Left ventricle dysfunction and co-morbidities are responsible for a large number of complications after coronary artery bypass graft (CABG) surgery. The best strategy for these patients, including the use or not and type of extracorporeal circulation (ECC), the use of minimized ECC (MECC), or conventional ECC (CECC), remains unclear. The aim of the present study was to investigate the potential effect of on-pump beating-heart (OPBH) surgery with the help of MECC for CABG in patients with a high-risk EuroSCORE and to compare this strategy to three other different procedures, including OPCAB and MECC or CECC with cardiac arrest.

Methods: Patients were included if their EuroSCORE was strictly >" xbd="1427" xhg="1404" ybd="1477" yhg="1440"/>9. Four groups were retrospectively compared: an OPCAB, an OPBH, a MECC and a CECC group under cardiac arrest.

Results: 214 patients, mean age 74.26 ± 8.5 years, 68.7% male, were operated. Mean EuroSCORE was 12.1 ± 2.9, left ventricular (LV) function 37.4 ± 12.3%, recent myocardial infarction (MI) 49.5%, renal failure 48.1%, chronic obstructive pulmonary disease (COPD) 42.2%, and peripheral vascular disease (PVD) 55.6%. Mean number of grafts per patient was 2.4 ± 0.7. Our study showed that it was possible, in very high-risk patients, to carry out revascularisation with OPBH similar to that using MECC or CECC under cardiac arrest (p=NS). This technique reduces troponin release (3.23 vs 6.56, p<0.01), postoperative myocardial complications (2% vs 8%, p<0.01), cardiotonic drug prescription (15.7% vs 31.3%, p<0.01), ventilation time (4.57H vs 6.48H, p<0.01) and length of stay (LOS) in ICU (2.16 vs 2.53, p=0.02).

Conclusion: The OPBH method seems to be safe, secure and effective in this population of very high-risk patients, reducing early complications and multi-organ failure. OPBH surgery, combining MECC without aortic cross-clamping, makes it possible to perform complete revascularization and is an interesting alternative for CABG in high-risk patients.
Parents’ and Children’s Beliefs About Peer Victimization
Authors: Harper Bridgette D.
Published: January 2011

This study examined how parents’ and children’s beliefs about peer victimization are related to children’s adjustment. A mediational model was proposed that addressed how adjustment is predicted by degree of victimization, as well as causal attributions of and coping responses to victimization. The participants were 100 fifth- or sixth-grade children and one of their parents (primarily mothers). Children’s ages ranged from 10 to12 years of age ( M = 10 years and 10 months, SD = 6 months). Using procedures recommended by Kenny, Kashy, and Bolger, mediational models were examined using multiple regression analyses. Results for child ratings supported the hypothesis that the association between peer victimization and psychosocial maladjustment is mediated through characterological blame attributions; this pattern of association was evident within parent-report data as well. Coping responses were not significant mediators in the models that examined the predictors of maladjustment from perceived victimization, attributions, and coping responses.
Applications of hybrid reachability analysis to robotic aerial vehicles
Authors: Gillula Jeremy H. , Hoffmann Gabriel M. , Haomiao Huang  , Vitus Michael P. , Tomlin Claire J.
Published: January 2011

The control of complex non-linear systems can be aided by modeling each system as a collection of simplified hybrid modes, with each mode representing a particular operating regime defined by the system dynamics or by a region of the state space in which the system operates. Guarantees on the safety and performance of such hybrid systems can still be challenging to generate, however. Reachability analysis using a dynamic game formulation with Hamilton—Jacobi methods provides a useful way to generate these types of guarantees, and the technique is flexible enough to analyze a wide variety of systems. This paper presents two applications of reachable sets, both focused on guaranteeing the safety and performance of robotic aerial vehicles. In the first example, reachable sets are used to design and implement a backflip maneuver for a quadrotor helicopter. In the second, reachability analysis is used to design a decentralized collision avoidance algorithm for multiple quadrotors. The theory for both examples is explained, and successful experimental results are presented from flight tests on the STARMAC quadrotor helicopter platform.
Power-SLAM: a linear-complexity, anytime algorithm for SLAM
Authors: Nerurkar Esha D , Roumeliotis Stergios I
Published: January 2011

In this paper, we present an extended Kalman filter (EKF)-based estimator for simultaneous localization and mapping (SLAM) with processing requirements that are linear in the number of features in the map. The proposed algorithm, called the Power-SLAM, is based on three key ideas. Firstly, by introducing the Global Map Postponement method, approximations necessary for ensuring linear computational complexity of EKF-based SLAM are delayed over multiple time steps. Then by employing the Power Method, only the most informative of the Kalman vectors, generated during the postponement phase, are retained for updating the covariance matrix. This ensures that the information loss during each approximation epoch is minimized. Next, linear-complexity, rank-2 updates, that minimize the trace of the covariance matrix, are employed to increase the speed of convergence of the estimator. The resulting estimator, in addition to being conservative as compared to the standard EKF, has processing requirements that can be adjusted depending on the availability of computational resources. Lastly, simulation and experimental results are presented that demonstrate the accuracy of the proposed algorithm (Power-SLAM) when compared to the standard EKF-based SLAM with quadratic computational cost and two linear-complexity competing alternatives.
Place-dependent people tracking
Authors: Luber Matthias , Diego Tipaldi Gian , Arras Kai O
Published: January 2011

People detection and tracking are important in many situations where robots and humans work and live together. But unlike targets in traditional tracking problems, people typically move and act under the constraints of their environment. The probabilities and frequencies for when people appear, disappear, walk or stand are not uniform but vary over space making human behavior strongly place-dependent. In this paper we present a model that encodes spatial priors on human behavior and show how the model can be incorporated into a people-tracking system. We learn a non-homogeneous spatial Poisson process that improves data association in a multi-hypothesis target tracker through more informed probability distributions over hypotheses. We further present a place-dependent motion model whose predictions follow the space-usage patterns that people take and which are described by the learned spatial Poisson process. Large-scale experiments in different indoor and outdoor environments using laser range data, demonstrate how both extensions lead to more accurate tracking behavior in terms of data-association errors and number of track losses. The extended tracker is also slightly more efficient than the baseline approach. The system runs in real-time on a typical desktop computer.
The costs and benefits of ‘red tape’: Anti-bureaucratic structure and gender inequity in a science research organization
Authors: Roth Wendy D. , Sonnert Gerhard
Published: January 2011

This paper explicates a central conflict that can affect science research organizations, the conflict between the anti-bureaucratic stance believed to advance science and concerns for gender equity rooted in the universalist ethos of science. We present a case study of a science research organization, using employment and publication records, a survey of 308 employees, and qualitative interviews with 60 employees. We show how anti-bureaucratic organizational structures perpetuate gender inequities for both female scientists and non-scientists.
Solid waste management in tropical Asia: what can we learn from Bali?
Authors: MacRae Graeme
Published: January 2011

Solid waste is a serious and growing problem thoughout tropical Asia. Waste management technologies and policies have not kept pace with the increase in waste production. The island of Bali in Indonesia is an atypical case in which both production and awareness of waste are relatively advanced. As such it is a useful case for exploring the wider problem and possible solutions. This article reviews the current state of solid waste management in Bali. It shows that there is a fundamental tension between large-scale industrial solutions and small-scale community-based ones, but that the most successful solutions to date are at intermediate scales. It argues that the reasons for this relative success are primarily social, cultural and political ones rather than technical or economic ones.
Vinasses: characterization and treatments
Authors: España-Gamboa Elda , Mijangos-Cortes Javier , Barahona-Perez Luis , Dominguez-Maldonado Jorge , Hernández-Zarate G , Alzate-Gaviria Liliana
Published: January 2011

The final products of the ethanol industry are alcoholic beverages, industrial ethanol and biofuels. They are produced by the same production process, which includes fermentation and distillation of raw materials which come from plant biomass. At the end of the distillation process a waste effluent is obtained called vinasse or stillage. The direct disposal of stillages on land or in groundwater (rivers, streams or lakes), or even for the direct irrigation of crops, pollutes the environment due to their high organic contents, dissolved solids and many other compounds which are toxic or could be contaminants under certain environmental conditions. This work reviews the characterization of vinasses from different feedstock sources and the main treatments for conditioning the soluble solids of vinasses before their disposal.
Optimization of enzymatic hydrolysis for ethanol production by simultaneous saccharification and fermentation of wastepaper
Authors: Sangkharak Kanokphorn
Published: January 2011

The present study investigated the development of high sugar production by optimization of an enzymatic hydrolysis process using both conventional and statistical methods, as well as the production of ethanol by the selected wastepaper source. Among four sources of pretreated wastepaper including office paper, newspaper, handbills and cardboard, office paper gave the highest values of cellulose (87.12%) and holocelluloses (89.07%). The effects of the amount of wastepaper, the pretreatment method and the type of enzyme on reducing sugar production from office paper were studied using conventional methods. The highest reducing sugar production (1851.28 µg L−1; 37.03% conversion of glucose) was obtained from the optimal condition containing 40 mg of office paper, pretreated with stream explosion and hydrolysed with the combination of cellulase from Aspergillus niger and Trichoderma viride at the fixed loading rate of 20 FPU g−1 sample. The effects of interaction of wastepaper amount and enzyme concentration as well as incubation time were studied by a statistical method using central composite design. The optimal medium composition consisted of 43.97 µg L−1, 28.14 FPU g−1 sample and 53.73 h of wastepaper, enzyme concentration and incubation time, respectively, and gave the highest amount of sugar production (2184.22 µg L−1) and percentage conversion of glucose (43.68%). The ethanol production from pretreated office paper using Saccharomyces cerevisiae in a simultaneous saccharification and fermentation process was 21.02 g L−1 after 36 h of cultivation, corresponding to an ethanol volumetric production rate of 0.58 g ethanol L−1 h−1.