bluuebunny/crossref_metadata_2025 huggingface dataset:
Trends in the use of of nephron‐sparing surgery (NSS) at an Australian tertiary referral centre: an analysis of surgical decision‐making using the R.E.N.A.L. nephrometry scoring system
Authors: Satasivam Prassannah , Rajarubendra Nieroshan , Chia Ping Han , Munshey Aasheen , Sengupta Shomik , Bolton Damien
Published: September 2011

Study Type – Therapy (case series)

Level of Evidence 4

What's known on the subject? and What does the study add?

Nephron‐sparing surgery (NSS) is increasingly recognised as a preferred form of management for the incidentally detected small renal mass (SRM). Within the context of equivalent oncological outcomes, patients treated by NSS may have a survival advantage over those treated by radical nephrectomy (RN) through a reduced risk of chronic kidney disease and its associated cardiac morbidity. Despite this, according to Medicare data from the USA, a disproportionate number of patients with SRMs continue to be treated with RN instead of NSS. Similar data from Australia are not yet available.

The present study explores the evolving management of SRMs at an Australian tertiary centre over a 5‐year period. It utilises the R.E.N.A.L. Nephrometry Score to assess how lesion complexity has influenced surgical decision‐making and charts the increasing use of NSS in the management of low‐complexity renal masses at our centre.

OBJECTIVE

To examine recent trends in the use of nephron‐sparing surgery (NSS) at our centre. Specifically, we sought to examine the process of surgical decision‐making by applying the R.E.N.A.L. nephrometry scoring system to assess the complexity of lesions for which surgery was undertaken.

PATIENTS AND METHODS

We performed a retrospective review of renal masses treated by surgery from January 2005 to December 2009, including 79 RN and 70 NSS.

CT images were available for analysis in 50 patients within each group.

Lesions were scored on the basis of their complexity using the R.E.N.A.L. nephrometry scoring system developed by Kutikov and Uzzo.

RESULTS

There was no difference in age between patients undergoing RN and NSS (median age 61 vs 60 years).

RN was performed for significantly larger lesions (mean [sd] 68 [9] vs 29 [2] mm, P < 0.05) of predominantly moderate and high complexity (12% low, 56% moderate, 32% high).

NSS was primarily used for low‐complexity lesions, but included four (8%) moderate‐complexity lesions in the final 2 years of the study.

The use of NSS increased from 28.6% of cases in 2005 to 60.0% of cases in 2009, which mirrored the increase in the proportion of operations performed for low‐complexity lesions (22.2% low‐complexity in 2005 to 70.6% in 2009, P < 0.01 for trend).

CONCLUSIONS

The increasing use of NSS at our institution mirrored the increasing treatment of low‐complexity renal lesions.

This may reflect an increased detection and referral of such lesions, or a shift towards treatment of lesions that in the past would have been under surveillance.

Practice at our centre reflects a shifting paradigm towards preferential use of NSS for the treatment of suitable renal masses.
Theta lingua franca: A common mid‐frontal substrate for action monitoring processes
Authors: Cavanagh James F. , Zambrano‐Vazquez Laura , Allen John J. B.
Published: September 2011

We present evidence that a multitude of mid‐frontal event‐related potential (ERP) components partially reflect a common theta band oscillatory process. Specifically, mid‐frontal ERP components in the N2 time range and error‐related negativity time range are parsimoniously characterized as reflections of theta band activities. Forty participants completed three different tasks with varying stimulus–response demands. Permutation tests were used to identify the dominant time–frequency responses of stimulus‐ and response‐locked conditions as well as the enhanced responses to novelty, conflict, punishment, and error. A dominant theta band feature was found in all conditions, and both ERP component amplitudes and theta power measures were similarly modulated by novelty, conflict, punishment, and error. The findings support the hypothesis that generic and reactive medial prefrontal cortex processes are parsimoniously reflected by theta band activities.
A Proposed Framework for Understanding the Forces behind Legislation of Universal Health Insurance—Lessons from Ten Countries
Authors: Wang C. Jason , Ellender Stacey M. , Textor Theodora , Bauchner Joshua H. , Wu Jen‐You , Bauchner Howard , Huang Andrew T.
Published: September 2011

Objective

To understand the forces propelling countries to legislate universal health insurance.

Data Source/Study Design

Descriptive review and exploratory synthesis of historic data on economic, geographic, socio‐demographic, and political factors.

Data Extraction Methods

We searched under “insurance, health” on MEDLINE and Google Scholar, and we reviewed relevant books and articles via a snowball approach.

Principal Findings

Ten countries with universal health insurance were studied. For the five countries that passed final universal insurance laws prior to 1958, we found that two forces of “historical context” (i.e., social solidarity and historic patterns), one “ongoing dynamic force” (political pressures), and “one uniqueness of the moment” force (legislative permissiveness) played a major role. For the five countries that passed final legislation between 1967 and 2010, the predominant factors were two “ongoing dynamic forces” (economic pressures and political pressures) and one “uniqueness of the moment” force (leadership). In general, countries in the former group made steady progress, whereas those in the latter group progressed in abrupt leaps.

Conclusions

The lessons of more recent successes—almost all of which were achieved via abrupt leaps—strongly indicate the importance of leadership in taking advantage of generalized economic and political pressures to achieve universal health insurance.
Hepatitis C virus nonstructural protein specific T cells are associated with virological responses to combination therapy in chronic HCV patients
Authors: Zhang Yonghong , Liu Yali , Zhao Yan , Shi Lingxian , Ma Lina , Yan Huiping , Wu Hao , Wei Lai , Dong Tao , Chen Xinyue
Published: September 2011

Background

Virus‐specific T‐cell responses play a major role in antiviral immune response. However, the effect of hepatitis C virus (HCV)‐specific T‐cell responses on combination therapy still remains controversial.

Aims

To identify the association between HCV‐specific T cell responses and efficiency of combination therapy.

Methods

To address this issue, a longitudinal analysis of HCV‐specific T‐cell responses to overlapping peptides covering HCV‐nonstructural protein (NS) was performed using ELISpot assay in 48 chronically infected HCV‐1b patients during combination treatment with peginterferon‐alfa and ribavirin.

Results

Fifty‐two percent of chronic HCV patients showed detectable HCV‐NS3, NS4 or NS5A specific T‐cell responses before therapy, with NS3 appearing to be the most immunodominant protein followed by NS5A and NS4. In addition, the percentage of patients responding to peptide stimulation was higher in patients with sustained virological response (SVR) when compared with those without SVR. Dynamics of HCV‐NS‐specific T‐cell responses were further analysed; we found that HCV‐specific T‐cell responses maintained higher levels at 12 weeks into treatment in patients with SVR. In contrast, HCV‐specific T‐cell responses in patients without SVR declined significantly at 4 weeks into treatment and maintained low levels at 12 weeks.

Conclusion

We found that the HCV‐specific T‐cell responses were associated with good viral control in patients with combination therapy.
INFLUENCE OF DIFFERENT LIGHT INTENSITIES AND DIFFERENT IRON NUTRITION ON THE PHOTOSYNTHETIC APPARATUS IN THE DIATOM CYCLOTELLA MENEGHINIANA (BACILLARIOPHYCEAE)1
Authors: Beer Anja , Juhas Matthias , Büchel Claudia
Published: September 2011

The diatom Cyclotella meneghiniana Kütz. (SAG 1020‐a) was cultured under high‐light (HL) and low‐light (LL) conditions with either high (12 μM) or low (1 μM) iron in the media. Changes in cell morphology, especially cell volume and chloroplast size, were observed in cells grown under low iron. In contrast, HL had a much stronger influence on the photosynthetic apparatus. PSII function was unimpaired under lowered iron supply, but its quantum efficiency and reoxidation rate were reduced under HL conditions. As reported before, HL induced changes in antenna polypeptide composition. Especially the amount of Fcp6, an antenna protein related to LI818 and known to be involved in photoprotection, was increased under HL but was significantly reduced under lowered iron. The diatoxanthin content correlated with the amount of Fcp6 in isolated FCPa antenna complexes and was thus increased under HL and reduced under low iron as well. While the diatoxanthin (Dt) content of whole cells was enhanced under HL, no decrease was observed under lowered iron supply, ruling out the possibility that the decreased amounts in FCPa were due to a hampered diadinoxanthin de‐epoxidase activity under these conditions. Thus, diatoxanthin not bound to FCPa has to be responsible for protection under the slight reduction in iron supply used here.
Anger Communication in Bicultural Adolescents
Authors: Novin Sheida , Rieffe Carolien
Published: September 2011

Little is known about bicultural adolescents’ emotional competence. The aim of the present study was to examine anger communication by comparing thirty‐eight 16‐year‐old Moroccan‐Dutch adolescents with 40 Dutch and 40 Moroccan peers using hypothetical anger‐eliciting vignettes. Findings show that although Moroccan and Dutch adolescents were equally likely to feel angry, they differed in their anger communication in accordance with their cultural models: Moroccan adolescents were more likely to express their anger indirectly than their Dutch counterparts, whereas Dutch adolescents were more likely to react directly or aggressively. Critically, the anger communication styles of the Moroccan‐Dutch youngsters fell in between the two monocultural groups.
Differences in Hours Worked in the OECD: Institutions or Fiscal Policies?
Authors: BERGER TINO , HEYLEN FREDDY
Published: September 2011

We study the determinants of the level and the evolution of per capita hours worked in a panel of OECD countries since the 1970s. Following Pesaran (2006), our empirical strategy allows for the possibility of cross‐sectionally correlated error terms due to unobserved common factors, which are potentially nonstationary. We find that much of the variation in per capita hours worked across countries and over time can be explained by differences in the level and structure of taxes and government expenditures. Differences in (the evolution of) labor and product market institutions have much less of a role to play. Our results show that a careful treatment of the time‐series properties of the data is crucial.
Rate‐Dependent AV Nodal Function: Closely Bound Conduction and Refractory Properties
Authors: TADROS RAFIK , BILLETTE JACQUES
Published: September 2011

Reconciled AV Nodal Conduction and Refractoriness. Introduction: The atrioventricular node (AV) node conducts slowly and filters atrial impulses. Puzzlingly, the recovery (conduction time vs atrial cycle length) and refractory curve (His bundle cycle length vs atrial cycle length) characterizing AV nodal function undergo disparate rate‐dependent changes. We sought the functional origin and significance of these disparate changes.

Methods and Results: Differences between the recovery and refractory curve were assessed in 30 steady state AV nodal responses (all potential paired combinations between 5 basic and 6 pretest cycle lengths imposed with S1S2S3 protocols) in rabbit heart preparations. Five of these responses corresponded to standard premature protocols. Both basic and pretest cycle length shortenings increased pretest conduction time that in turn equally shortened the ensuing His‐atrial interval at all test cycle lengths. This effect was mathematically predictable and tended to shift the refractory curve downward whereas not affecting the recovery curve. Moreover, increases in pretest conduction time also shifted the recovery and refractory curve equally rightward on their x‐axis, thereby biasing curve comparison between steady states. This problem could be overcome with equivalent results either by accordingly correcting the atrial cycle length or by using the His‐atrial interval as the recovery index.

Conclusion: Recovery and refractory curves from AV nodal steady state responses including standard premature protocols only differ by the His‐atrial interval that decreases with the pretest conduction time. The latter also biases curve comparison between steady states. Rate‐dependent AV nodal function is best assessed with recovery curves freed from changes in pretest conduction time. (J Cardiovasc Electrophysiol, Vol. 23 p. 302‐308, March 2012.)
Cytochrome c maturation system on the negative side of bioenergetic membranes: CCB or System IV
Authors: de Vitry Catherine
Published: September 2011

Cytochromes of the c‐type contain hemes covalently attached via one or, more generally, two thioether bonds between the vinyls of heme b and the thiols of cysteine residues of apocytochromes. This post‐translational modification relies on membrane‐associated specific biogenesis proteins, referred to as cytochrome c maturation systems. At least three different versions (i.e. Systems I–III) are found on the positive side of bioenergetic membranes in different organisms and compartments. The present minireview is concerned with systems on the negative side of the membranes. It describes System IV, also referred to as cofactor assembly on complex C subunit B, for heme binding on cytochrome b6 through one thioether bond; this covalent heme is usually called ci. This system is found in all organisms with oxygenic photosynthesis but not in Firmicutes, although they also have a cytochrome b protein with an additional heme ci covalently attached via a single thioether bond.
A Fresh Look at U.S. Water and Wastewater Infrastructure: The Commercial and Environmentally Sustainable Path Forward
Authors: Haarmeyer David
Published: September 2011

The growing scarcity of water has a silver lining: water is being transformed into an economic resource whose price will better reflect its true value and thus encourage conservation and stimulate new supplies. This in turn can be expected to put more pressure on water and wastewater organizations to become both commercially and environmentally sustainable. And by making its decision‐making more consistent with economic criteria, the U.S. water industry will be in a better position to address its four major challenges: insufficient capital; industry fragmentation; paucity of innovations; and lack of environmental sustainability.

The EPA estimates that maintenance and upgrades of public water systems will require over $344 billion in investment over the next 20 years. The good news, however, is that institutional investors have found major long‐term investment opportunities in water and wastewater infrastructure in the U.K., and have also established a small toehold in the U.S. Focused on increasing the value of the assets they purchase, such active investors can be expected to bring investment discipline as well as capital to water utilities.

A more rational approach to the industry's economics will facilitate consolidation of what is a highly fragmented industry, thereby reducing service costs and increasing access to capital, which is badly needed by small U.S. community systems. Contributing further to cost reductions and increased access to capital, a vibrant and commercially oriented industry should also spawn valuable innovation. Finally, more accountable and well‐governed water organizations can become natural leaders in achieving environmental sustainability by ensuring that water is priced to reflect its true costs and that water resources are conserved for the future.
Infrastructure Public‐Private Partnerships: “Partnerships” Come to Fruition
Authors: Offutt J. Perry , Runde James , Selinger Stacie D.
Published: September 2011

P3s are generally structured as long‐term leases of municipal assets like toll roads, ports, and airports by private investors/operators. Five years ago, municipalities viewed such partnerships primarily as a means of raising capital, and they often viewed maximizing the up‐front proceeds as the primary goal of the transactions.

Today's P3s have been re‐defined to focus beyond the bottom line and toward the goal of developing sustainable long‐term partnerships between the public and private sectors. As three transactions from the past year are used to demonstrate, the P3 has emerged as a way for governments to achieve sustainable reinvestment in needed infrastructure while also using the best practices of the private sector to increase the efficiency of and revenue from their asset operations.
Energy Infrastructure Investment and the Rise of the Uncorporation1
Authors: Ribstein Larry E.
Published: September 2011

While most large U.S. businesses have long been organized as corporations, a significant portion of our economy, including major parts of our energy infrastructure, are organized as other types of legal entities. These “uncorporations” include such business forms as Master Limited Partnerships (MLPs) and Limited Liability Companies (LLCs).

Many practitioners have dismissed these alternative entities as merely tax devices and only peripherally important to mainstream business. But this view misses important features of the uncorporation that make it an important alternative in dealing with the “agency” costs that arise in public companies from separating managerial control from equity ownership. Corporate governance relies heavily on agents such as auditors, class action lawyers, judges, and independent directors to protect shareholders from managerial self‐interest. The obvious costs and defects of relying on these governance mechanisms have generally been seen as a reasonable price to pay for the benefits of the corporate form.

But this conclusion depends on the availability and effectiveness of the alternative mechanisms for addressing agency costs. Uncorporations provide such an alternative by tying managers' economic well‐being so closely to that of their firms that corporate monitoring devices become less necessary. Uncorporate governance mechanisms include managerial compensation that is based largely (if not entirely) on the firm's profits or cash distributions, and restrictions on managers' control of corporate cash through liquidation rights and requirements for cash distributions. Business people and policy makers should evaluate the potential benefits of uncorporations before concluding that the costs of corporate governance are an inevitable price of separating ownership and control in modern firms.
Simulating natural selection in landscape genetics
Authors: LANDGUTH E. L. , CUSHMAN S. A. , JOHNSON N. A.
Published: September 2011

Linking landscape effects to key evolutionary processes through individual organism movement and natural selection is essential to provide a foundation for evolutionary landscape genetics. Of particular importance is determining how spatially‐explicit, individual‐based models differ from classic population genetics and evolutionary ecology models based on ideal panmictic populations in an allopatric setting in their predictions of population structure and frequency of fixation of adaptive alleles. We explore initial applications of a spatially‐explicit, individual‐based evolutionary landscape genetics program that incorporates all factors – mutation, gene flow, genetic drift and selection – that affect the frequency of an allele in a population. We incorporate natural selection by imposing differential survival rates defined by local relative fitness values on a landscape. Selection coefficients thus can vary not only for genotypes, but also in space as functions of local environmental variability. This simulator enables coupling of gene flow (governed by resistance surfaces), with natural selection (governed by selection surfaces). We validate the individual‐based simulations under Wright‐Fisher assumptions. We show that under isolation‐by‐distance processes, there are deviations in the rate of change and equilibrium values of allele frequency. The program provides a valuable tool (cdpopv1.0;http://cel.dbs.umt.edu/software/CDPOP/) for the study of evolutionary landscape genetics that allows explicit evaluation of the interactions between gene flow and selection in complex landscapes.
Pharmacodynamic Monitoring of CanineT‐Cell Cytokine Responses to Oral Cyclosporine
Authors: Archer T.M. , Fellman C.L. , Stokes J.V. , Pinchuk L.M. , Lunsford K.V. , Pruett S.B. , Langston V.C. , Mackin A.J.
Published: September 2011

Background

Pharmacodynamic assays measure the immunosuppressive effects of cyclosporine onT‐cells and offer an alternative assessment of efficacy in individual patients.

Objective

To assess the immunosuppressive effects of high and low dosage cyclosporine on canineT‐cells and to develop a novel testing system for individualized dose adjustment.

Animals

Seven healthy femaleWalker hounds.

Methods

Experimental study using a paired comparison design. Flow cytometry was used to measureT‐cell expression ofIL‐2,IL‐4, andIFN‐γ. Cytokine expression 8 days after oral administration of high and low dosages of cyclosporine was compared to baseline and washout values, respectively. The high dosage was initially 10 mg/kg q12h and was then adjusted to attain established immunosuppressive trough blood drug concentrations (>600 ng/mL). The low dosage was 5 mg/kg q24h.

Results

High dosage cyclosporine resulted in significant decreases inIL‐2 andIFN‐γ expression (P = .0156,P = .0156), but notIL‐4 expression (P = .2188). Low dosage cyclosporine was associated with a significant decrease inIFN‐γ expression (P = .0156), whileIL‐2 expression was not affected (P = .1094).

Conclusions and Clinical Importance

T‐cell function is suppressed at trough blood drug concentrations exceeding 600 ng/mL, and is at least partially suppressed in some dogs at low dosages. Direct evaluation ofT‐cell function could be an effective, more sensitive alternative to measuring blood drug concentrations for monitoring immunosuppressive therapy.
Laboratory experiments bearing on the origin and evolution of olivine‐rich chondrules
Authors: RICHTER Frank M. , MENDYBAEV Ruslan A. , CHRISTENSEN John N. , EBEL Denton , GAFFNEY Amy
Published: September 2011

Abstract– Evaporation rates of K2O, Na2O, and FeO from chondrule‐like liquids and the associated potassium isotopic fractionation of the evaporation residues were measured to help understand the processes and conditions that affected the chemical and isotopic compositions of olivine‐rich type IA and type IIA chondrules from Semarkona. Both types of chondrules show evidence of having been significantly or totally molten. However, these chondrules do not have large or systematic potassium isotopic fractionation of the sort found in the laboratory evaporation experiments. The experimental results reported here provide new data regarding the evaporation kinetics of sodium and potassium from a chondrule‐like melt and the potassium isotopic fractionation of evaporation residues run under various conditions ranging from high vacuum to pressures of one bar of H2+CO2, or H2, or helium. The lack of systematic isotopic fractionation of potassium in the type IIA and type IA chondrules compared with what is found in the vacuum and one‐bar evaporation residues is interpreted as indicating that they evolved in a partially closed system where the residence time of the surrounding gas was sufficiently long for it to have become saturated in the evaporating species and for isotopic equilibration between the gas and the melt. A diffusion couple experiment juxtaposing chondrule‐like melts with different potassium concentrations showed that the diffusivity of potassium is sufficiently fast at liquidus temperatures (DK > 2 × 10−4cm2 s−1 at 1650 °C) that diffusion‐limited evaporation cannot explain why, despite their having been molten, the type IIA and type IA chondrules show no systematic potassium isotopic fractionation.
Gebel Kamil: The iron meteorite that formed the Kamil crater (Egypt)
Authors: D’ORAZIO Massimo , FOLCO Luigi , ZEOLI Antonio , CORDIER Carole
Published: September 2011

Abstract– The 45 m in diameter Kamil impact crater was formed <5000 yr ago in the eastern Sahara, close to the southern border of modern Egypt. The original features of this structure, including thousands of fragments of the meteorite impactor, are extremely well preserved. With the exception of a single 83 kg regmaglypted individual, all specimens of Gebel Kamil (the iron meteorite that formed the Kamil crater) are explosion fragments weighing from <1 g to 34 kg. Gebel Kamil is an ungrouped Ni‐rich (about 20 wt% Ni) ataxite characterized by high Ge and Ga contents (approximately 120 μg g−1 and approximately 50 μg g−1, respectively) and by a very fine‐grained duplex plessite metal matrix. Accessory mineral phases in Gebel Kamil are schreibersite, troilite, daubréelite, and native copper. Meteorite fragments are cross‐cut by curvilinear shear bands formed during the explosive terrestrial impact. A systematic search around the crater revealed that meteorite fragments have a highly asymmetric distribution, with greater concentrations in the southeast sector and a broad maximum in meteorite concentration in the 125–160° N sector at about 200 m from the crater rim. The total mass of shrapnel specimens >10 g, inferred from the density map compiled in this study is 3400 kg. Field data indicate that the iron bolide approached the Earth’s crust from the northwest (305–340° N), travelling along a moderately oblique trajectory. Upon hypervelocity impact, the projectile was disrupted into thousands of fragments. Shattering was accompanied by some melting of the projectile and of the quartz‐arenite target rocks, which also suffered shock metamorphism.
Pharmacokinetics and distribution of minocycline in mature horses after oral administration of multiple doses and comparison with minimum inhibitory concentrations
Authors: SCHNABEL L. V. , PAPICH M. G. , DIVERS T. J. , ALTIER C. , APREA M. S. , McCARREL T. M. , FORTIER L. A.
Published: September 2011

Reasons for performing study: Minocycline holds great potential for use in horses not only for its antimicrobial effects but also for its anti‐inflammatory and neuroprotective properties. However, there are no pharmacokinetic or safety data available regarding the use of oral minocycline in horses.

Objectives: To determine pharmacokinetics, safety and penetration into plasma, synovial fluid, aqueous humour (AH) and cerebral spinal fluid (CSF) of minocycline after oral administration of multiple doses in horses and to determine the minimum inhibitory concentrations (MIC) of minocycline for equine pathogenic bacteria.

Methods: Six horses received minocycline (4 mg/kg bwt q. 12 h for 5 doses). Thirty‐three blood and 9 synovial fluid samples were collected over 96 h. Aqueous humour and CSF samples were collected 1 h after the final dose. Minocycline concentrations were measured using high pressure liquid chromatography. The MIC values of minocycline for equine bacterial isolates were determined.

Results: At steady state, the mean ± s.d. peak concentration of minocycline in the plasma was 0.67 ± 0.26 µg/ml and the mean half‐life was 11.48 ± 3.23 h. The highest trough synovial fluid minocycline concentration was 0.33 ± 0.12 µg/ml. The AH concentration of minocycline was 0.09 ± 0.03 µg/ml in normal eyes and 0.11 ± 0.04 µg/ml in blood aqueous barrier‐disrupted eyes. The mean CSF concentration of minocycline was 0.38 ± 0.09 µg/ml. The MIC values were determined for 301 isolates. Minocycline concentrations were above the MIC50 and MIC90 for many gram‐positive equine pathogens.

Potential relevance: This study supports the use of orally administered minocycline at a dose of 4 mg/kg bwt every 12 h for the treatment of nonocular infections caused by susceptible (MIC≤0.25 µg/ml) organisms in horses. Further studies are required to determine the dose that would be effective for the treatment of ocular infections.
Studies towards the N-acylative kinetic resolution of NOBIN
Authors: Arseniyadis Stellios , Mahesh Mohan , McDaid Paul , Hampel Thomas , Davey Stephen G. , Spivey Alan C.
Published: September 2011

An investigation into theN-acylation of atropisomeric anilines8and2, which are related to NOBIN (1), catalysed by small molecule chiral pyridine-based nucleophilic catalysts is described. The first organocatalytic kinetic resolution (KR) of an atropisomeric aniline is described.
Yield of catheter angiography in patients with intracerebral hemorrhage with and without intraventricular extension
Authors: Kadkhodayan Yasha , Almandoz Josser E Delgado , Kelly James E , Kale Sushant P , Jagadeesan Bharathi D , Moran Christopher J , Cross DeWitte T , Derdeyn Colin P
Published: September 2011

Background and aim

The role of imaging for the detection of vascular lesions in patients with intracerebral hemorrhage (ICH) is poorly defined. A study was undertaken to compare the yield of digital subtraction angiography (DSA) in patients with ICH with intraventricular hemorrhage (IVH) and those without IVH.

Methods

The DSA database at our institution was reviewed for patients who underwent DSA for acute spontaneous ICH over a period of 68 months. Patients with known vascular malformation or brain neoplasm, prior surgery, ischemic infarction, subarachnoid hemorrhage or isolated IVH were excluded. Patients were grouped into those with associated IVH (group A) and those without (group B). Baseline demographic and clinical data, non-contrast head CT (NCCT) probability for a vascular lesion and angiographic results were compared.

Results

293 patients met the inclusion and exclusion criteria (141 women, 152 men, mean age 57, range 18–88), 139 in group A and 154 in group B. Age and sex distributions were similar (p>0.05). Group A patients were more likely to be hypertensive or coagulopathic (p=0.001). Group B had more patients with high probability NCCT scans (p<0.001). Underlying vascular lesions were found in 21 patients (15.1%) in group A and 34 (22.1%) in group B (p>0.05).

Conclusion

The presence of IVH in patients with acute spontaneous ICH is not associated with an increased risk of an underlying vascular lesion and should not be used to select patients for neurovascular evaluation.
Polyphosphazenes containing lactic acid ester and methoxyethoxyethoxy side groups — Thermosensitive properties and, in vitro degradation, and biocompatibility
Authors: Bi Yunmei , Gong Xiaoying , He Feng , Xu Li , Chen Lin , Zeng Xianghui , Yu Li
Published: September 2011

The thermosensitive and hydrolytic properties and biocompatibility of polyphosphazenes containing lactic acid ester and methoxyethoxyethoxy as co-substitutents were investigated. Depending on the type of lactic acid ester, these polyphosphazenes exhibited lower critical solution temperatures (LCST) (from 33 to 52 °C), which were almost concentration-independent in the range of 1.5 to 15 wt% of the polymers in aqueous solution. The salt effect on the thermosensitivity of the polymers was studied by measuring their LCST in aqueous solutions containing various salts. Bu4NBr and KI showed salting-in effects among the tested six salts, but NH4Br, NaBr, NH4Cl, and NaCl showed salting-out effects. Hydrolysis studies showed the rate of polymer hydrolysis decreased in the order of basic > acidic > neutral solution. The polyphosphazene with bulkier and more hydrophobic ester groups was more stable in hydrolysis. The results of a cytotoxicity study using an MTT assay method with HepG2 cell and K562/VCR cell showed that these polyphosphazenes and their degradation products were biocompatible. The thermoresponsiveness and biocompatibility of these biodegradable polyphosphazenes may favor the polymers as potential stimuli-responsive materials in biomedical applications.
INTERVAL METHODS IN KNOWLEDGE REPRESENTATION
Authors: Kreinovich Vladik
Published: September 2011

Please send your abstracts (or copies of papers that you want to see reviewed here) to vladik@utep.edu, or by regular mail to Vladik Kreinovich, Department of Computer Science, University of Texas at El Paso, El Paso, TX 79968, USA.
CONVENIENT MULTIPLE DIRECTIONS OF STRATIFICATION
Authors: JOURDAIN BENJAMIN , LAPEYRE BERNARD , SABINO PIERGIACOMO
Published: September 2011

This paper investigates the use of multiple directions of stratification as a variance reduction technique for Monte Carlo simulations of path-dependent options driven by Gaussian vectors. The precision of the method depends on the choice of the directions of stratification and the allocation rule within each strata. Several choices have been proposed but, even if they provide variance reduction, their implementation is computationally intensive and not applicable to realistic payoffs, in particular not to Asian options with barrier. Moreover, all these previously published methods employ orthogonal directions for multiple stratification. In this work we investigate the use of algorithms producing convenient directions, generally non-orthogonal, combining a lower computational cost with a comparable variance reduction. In addition, we study the accuracy of optimal allocation in terms of variance reduction compared to the Latin Hypercube Sampling. We consider the directions obtained by the Linear Transformation and the Principal Component Analysis. We introduce a new procedure based on the Linear Approximation of the explained variance of the payoff using the law of total variance. In addition, we exhibit a novel algorithm that permits to correctly generate normal vectors stratified along non-orthogonal directions. Finally, we illustrate the efficiency of these algorithms in the computation of the price of different path-dependent options with and without barriers in the Black-Scholes and in the Cox-Ingersoll-Ross markets.
DYNAMIC CHARACTERISTICS OF THE KAO PING HSI BRIDGE UNDER SEISMIC LOADING WITH FOCUS ON CABLE SIMULATION
Authors: LIU MING-YI , LIN LI-CHIN , WANG PAO-HSII
Published: September 2011

The objective of this study is to thoroughly investigate the dynamic characteristics of the Kao Ping Hsi Bridge located in southern Taiwan. A one-element cable system (OECS) and a multi-element cable system (MECS) are presented for simulating the dynamic properties of the cables of the bridge. By a finite element computation procedure, the initial shape, modal, and seismic analyses are conducted for the bridge using either the OECS or MECS model. A hybrid method combining both the two-loop iteration and the catenary function is proposed to determine the initial shapes using the MECS model. Convergent and smooth initial shapes can be obtained using such a method. The results indicate that the OECS model can yield solution in an efficient way, whereas the MECS model should be used if solutions of greater accuracy are desired.
Activation of GABAA receptors modulates all stages of mechanoreception in spider mechanosensory neurons
Authors: Pfeiffer Keram , Torkkeli Päivi H. , French Andrew S.
Published: September 2011

GABAA receptors mediate mainly inhibitory effects, but there are also many examples of excitatory effects in both mammalian and invertebrate preparations. Here, we aimed to create a complete, quantitative picture of GABAA-mediated excitation in a mechanosensory neuron where this phenomenon has been well established. We used muscimol to activate GABAA receptors in spider VS-3 neurons and measured the dynamic behavior independently and separately at each of three stages of mechanoreception (receptor current, receptor potential, and action potentials) before and during modulation. We calculated frequency response functions between each stage, estimated information as signal entropy, and estimated information capacity from coherence. Since coherence is sensitive to both noise and nonlinearity, we measured signal-to-noise separately at each stage by averaging responses to repeated mechanical inputs. Muscimol depolarized VS-3 neurons and, after brief inhibition, increased their firing rates. During this excitation, we found significant changes at each stage. Receptor current was attenuated but became more selective to high frequencies. Membrane impedance and time constant fell, favoring higher frequency transmission from receptor current to receptor potential. Action potential firing increased and had higher total entropy. Information capacity from signal-to-noise was always much higher than from coherence, confirming that intracellular noise does not limit signal transmission in these neurons. We conclude that GABAA receptor activation shifts each stage of mechanotransduction to higher frequency sensitivity, while the elevated firing rate increases the amount of information that can be encoded. These results show that a single neurotransmitter can finely modulate a sensory neuron's sensitivity and ability to transmit information.
Revisiting the Marrow Metabolic Changes after Chemotherapy in Lymphoma: A Step towards Personalized Care
Authors: Tang Bingfeng , Patel Malaykumar M. , Wong Regina H. , Wood Daniel , Wong Christiana O. , Wu Dafang , Khong Pek Lan , Wong Ching Yee Oliver
Published: September 2011

Purpose. The aims were to correlate individual marrow metabolic changes after chemotherapy with bone marrow biopsy (BMBx) for its potential value of personalized care in lymphoma. Methods. 26 patients (mean age, 58 ± 15 y; 13 female, 13 male) with follicular lymphoma or diffuse large B-cell lymphoma, referred to FDG-PET/CT imaging, who had BMBx from unilateral or bilateral iliac crest(s) before chemotherapy, were studied retrospectively. The maximal standardized uptake value (SUV) was measured from BMBx site over the same area on both initial staging and first available restaging FDG-PET/CT scan. Results. 35 BMBx sites in 26 patients were evaluated. 12 of 35 sites were BMBx positive with interval decrease in SUV in 11 of 12 sites (92%). The remaining 23 of 35 sites were BMBx negative with interval increase in SUV in 21 of 23 sites (91%). The correlation between SUV change over the BMBx site before and after chemotherapy and BMBx result was significant (P<0.0001). Conclusions. This preliminary result demonstrates a strong correlation between marrow metabolic changes (as determined by FDG PET) after chemotherapy and bone marrow involvement proven by biopsy. This may provide a retrospective means of personalized management of marrow involvement in deciding whether to deliver more extended therapy or closer followup of lymphoma patients.
Community Outreach and Cardiovascular Health (COACH) Trial
Authors: Allen Jerilyn K. , Dennison-Himmelfarb Cheryl R. , Szanton Sarah L. , Bone Lee , Hill Martha N. , Levine David M. , West Murray , Barlow Amy , Lewis-Boyer LaPricia , Donnelly-Strozzo Mary , Curtis Carol , Anderson Katherine
Published: September 2011

Background—

Despite well-publicized guidelines on the appropriate management of cardiovascular disease and type 2 diabetes, the implementation of risk-reducing practices remains poor. This report describes the results of a randomized, controlled clinical trial evaluating the effectiveness of a comprehensive program of cardiovascular disease risk reduction delivered by nurse practitioner /community health worker (NP/CHW) teams versus enhanced usual care (EUC) to improve lipids, blood pressure, glycated hemoglobin (HbA1c), and patient perceptions of the quality of their chronic illness care in patients in urban community health centers.

Methods and Results—

A total of 525 patients with documented cardiovascular disease, type 2 diabetes, hypercholesterolemia, or hypertension and levels of LDL cholesterol, blood pressure, or HbA1c that exceeded goals established by national guidelines were randomly assigned to NP/CHW (n=261) or EUC (n=264) groups. The NP/CHW intervention included aggressive pharmacological management and tailored educational and behavioral counseling for lifestyle modification and problem solving to address barriers to adherence and control. Compared with EUC, patients in the NP/CHW group had significantly greater 12-month improvement in total cholesterol (difference, 19.7 mg/dL), LDL cholesterol (difference,15.9 mg/dL), triglycerides (difference, 16.3 mg/dL), systolic blood pressure (difference, 6.2 mm Hg), diastolic blood pressure (difference, 3.1 mm Hg), HbA1c (difference, 0.5%), and perceptions of the quality of their chronic illness care (difference, 1.2 points).

Conclusions—

An intervention delivered by an NP/CHW team using individualized treatment regimens based on treat-to-target algorithms can be an effective approach to improve risk factor status and perceptions of chronic illness care in high-risk patients.

Clinical Trial Registration—

URL:
http://www.clinicaltrials.gov
. Unique identifier: NCT00241904.
The Influence of Dimensionality on Parameter Estimation Accuracy in the Generalized Graded Unfolding Model
Authors: Carter Nathan T. , Zickar Michael J.
Published: September 2011

The generalized graded unfolding model (GGUM) is an ideal point model of responding that is consistent with the Thurstonian theory of respondent behavior. Ideal point models have recently generated interest in the realms of attitude and personality assessment. One unclear aspect of applying ideal point models is the influence of multidimensionality on GGUM item and person parameters estimation accuracy. Using simulated data, the authors tested the influence of the balance, or ratio, of items loading onto two dimensions, the degree of bidimensionality and sample size on parameter estimation accuracy. The results suggest that bidimensionality and the proportion of items loading onto a second trait increases estimation error. The second trait was chosen in estimation when a large number of the items in the survey reflected a highly irrelevant second trait. Estimation error was greater for persons and items at the extreme ends of the continuum; positive estimates were biased upward and positive parameters downward. The results suggest that although the GGUM chooses another trait in estimation, in most cases conventional fit analyses and checks for item parameter extremity are likely to be successful in identifying items measuring another trait. Furthermore, the conditions in which the trait being estimated may not be clear should be rare in practice. The implications of these results for researchers who wish to apply these models to real-life data are discussed.
Equivalence of Reading and Listening Comprehension Across Test Media
Authors: Schroeders Ulrich , Wilhelm Oliver
Published: September 2011

Whether an ability test delivered on either paper or computer provides the same information is an important question in applied psychometrics. Besides the validity, it is also the fairness of a measure that is at stake if the test medium affects performance. This study provides a comprehensive review of existing equivalence research in the field of reading and listening comprehension in English as a foreign language and specifies factors that are likely to have an impact on equivalence. Taking into account these factors, comprehension measures were developed and tested with N = 442 high school students. Using multigroup confirmatory factor analysis, it is shown that reading and listening comprehension both were measurement invariant across test media. Nevertheless, it is argued that equivalence of data gathered on paper and computer depends on the specific measure or construct, the participants or the recruitment mechanisms, and the software and hardware realizations. Therefore, equivalence research is required for specific instantiations unless generalizable knowledge about factors affecting equivalence is available. Multigroup confirmatory factor analysis is an appropriate and effective tool for the assessment of the comparability of test scores across test media.
Language and Culture Effects on Gender Classification of Objects
Authors: Nicoladis Elena , Foursha-Stevenson Cassandra
Published: September 2011

The present studies test whether French grammatical gender affects bilingual children’s classification of objects as boys or girls in English, in children aged 3 to 5 years (Study 1) and aged 8 to 10 years (Study 2), compared to monolingual children to control for possible cultural biases. In both studies, children tended to classify more objects as boys than as girls. In Study 1, the bilingual children showed a reduced boy bias relative to monolinguals. Only the older children showed a by-object effect of French gender. The bilinguals’ and monolinguals’ classifications were highly correlated. In Study 3, English-speaking adults classified object names as boys or girls. The adults’ classifications were highly correlated with the children’s. The authors argue that the classification of objects by gender is affected by cultural biases as well as knowledge of French. The effect of French knowledge is modified by age.
The influences of progression type and distortion on the perception of terminal power chords
Authors: Juchniewicz Jay , Silverman Michael J.
Published: September 2011

The purpose of this study was to investigate the tonal perception and restoration of thirds within power chords with the instruments and sounds idiosyncratic to the Western rock/pop genre. Four separate chord sequences were performed on electric guitar in four versions; as full chord and power chord versions as well as under both clean-tone and distortion effect versions. Undergraduate music majors ( N = 50) listened to all 16 chord progressions and rated their perception of the tonality (‘majorness’ or ‘minorness’) in the terminal chord for each sequence, utilizing a 7-point semantic differential scale ranging from minor (1) to major (7) with a neutral indicator located in the middle (4). Participants had completed a mean 3.82 ( SD = 0.66) semesters of ear training and 28 indicated they played the guitar. A three-way repeated measures ANOVA revealed significant differences between responses for chord sequences (1–4), as well as a significant interaction between chord sequences, distortion (clean versus distortion), and type of chords in the progression (whole chords versus power chords). Further analysis of data indicated that participants tended to perceive terminal power chords as major, especially when progressions were comprised of power chords and contained distortion.