bluuebunny/crossref_metadata_2025 huggingface dataset:
The sensitivity of land emissivity estimates from AMSR-E at C and X bands to surface properties
Authors: Norouzi H. , Temimi M. , Rossow W. B. , Pearl C. , Azarderakhsh M. , Khanbilvardi R.
Published: November 2011

Abstract. Microwave observations at low frequencies exhibit more sensitivity to surface and subsurface properties with little interference from the atmosphere. The objective of this study is to develop a global land emissivity product using passive microwave observations from the Advanced Microwave Scanning Radiometer – Earth Observing System (AMSR-E) and to investigate its sensitivity to land surface properties. The developed product complements existing land emissivity products from SSM/I and AMSU by adding land emissivity estimates at two lower frequencies, 6.9 and 10.65 GHz (C- and X-band, respectively). Observations at these low frequencies penetrate deeper into the soil layer. Ancillary data used in the analysis, such as surface skin temperature and cloud mask, are obtained from International Satellite Cloud Climatology Project (ISCCP). Atmospheric properties are obtained from the TIROS Operational Vertical Sounder (TOVS) observations to determine the small upwelling and downwelling atmospheric emissions as well as the atmospheric transmission. A sensitivity test confirms the small effect of the atmosphere but shows that skin temperature accuracy can significantly affect emissivity estimates. Retrieved emissivities at C- and X-bands and their polarization differences exhibit similar patterns of variation with changes in land cover type, soil moisture, and vegetation density as seen at SSM/I-like frequencies (Ka and Ku bands). The emissivity maps from AMSR-E at these higher frequencies agree reasonably well with the existing SSM/I-based product. The inherent discrepancy introduced by the difference between SSM/I and AMSR-E frequencies, incidence angles, and calibration has been assessed. Significantly greater standard deviation of estimated emissivities compared to SSM/I land emissivity product was found over desert regions. Large differences between emissivity estimates from ascending and descending overpasses were found at lower frequencies due to the inconsistency between thermal IR skin temperatures and passive microwave brightness temperatures which can originate from below the surface. The mismatch between day and night AMSR-E emissivities is greater than ascending and descending differences of SSM/I emissivity. This is because of unique orbit time of AMSR-E (01:30 a.m./p.m. LT) while other microwave sensors have orbit time of 06:00 to 09:00 (a.m./p.m.). This highlights the importance of considering the penetration depth of the microwave signal and diurnal variability of the temperature in emissivity retrieval. The effect of these factors is greater for AMSR-E observations than SSM/I observations, as AMSR-E observations exhibit a greater difference between day and night measures. This issue must be addressed in future studies to improve the accuracy of the emissivity estimates especially at AMSR-E lower frequencies.
Differentiation of Embryonic Stem Cells into Neural Cells on 3D Poly (D, L-Lactic Acid) Scaffolds versus 2D Cultures
Authors: Zare-Mehrjardi Narges , Khorasani Mohammad Taghi , Hemmesi Katayoun , Mirzadeh Hamid , Azizi Hossein , Sadatnia Behrouz , Hatami Maryam , Kiani Sahar , Barzin Jalal , Baharvand Hossein
Published: November 2011

In this study, a highly porous poly (D, L-lactic acid) (PDLLA) scaffold was designed and fabricated using dioxane and thermal-induced phase separation (TIPS) methods (liquid-liquid and solid-liquid). Additionally, we characterized the ability of mouse embryonic stem cells (ESCs) to differentiate into neural cells in PDLLA scaffold with uniform porosity, interconnectivity, and high porosity, and then compared them with cells seeded under conventional two-dimensional (2D) culture conditions. Histochemistry staining showed the migration of differentiated cells through the scaffold. Immunofluorescence analysis of the differentiated cells by counting positive cells revealed that the PDLLA scaffold resulted in a significantly greater number of neural markers, microtubule associated protein-2, β-tubulin III, neurofilament protein, and glial fibrillary acidic protein (the astrocyte marker) when compared to those in 2D culture condition. Moreover, the expression of Nestin, Mash1, Pax6, and HB9 increased significantly in 3D scaffolds when compared with 2D cultures as detected by semi-quantitative RT-PCR. Scanning electron microscopy of differentiated neurons on scaffolds also demonstrated favorable results for neurite outgrowth. The results of this study demonstrated a promising effect of 3D scaffold culture for neural cell differentiation from ESCs in prospective tissue engineering applications.
The Middle Arm Arteriovenous Fistula is an Additional Option to Expand Autogenous Hemodialysis Access
Authors: Capurro Federica , De Mauri Andreana , Navino Carlo , David Paola , Chiarinotti Doriana , De Leo Martino
Published: November 2011

Purpose

the native artero-venous fistula is the gold standard for hemodialysis access. Unfortunately, the wrist fistula is often not practical and the upper arm fistula is hindered by several complications. The aim of this study is to assess the safety of the middle-arm fistula as additional native access.

Methods

we reviewed and compared the patency rates at 12, 48, and 60 months of distal, middle, and upper arm fistula performed from January 2003 to December 2008. For diabetic and old patients we compared distal and middle-arm fistulas.

Results

of 273 native access, 149 (54.6%) were distal, 92 (33.7%) middle-arm, and 32 (11.7%) upper fistula. Patency rates were 81%, 58%, and 52% for distal, 85%, 69%, and 69% for middle-arm, and 82%, 46%, and 29% for upper arm fistula (P NS). Patency rates were 92%, 70%, and 54% in middle-arm fistula as first access and 80%, 71%, and 71% in middle-arm fistula as a rescue access (P NS). Among patients > 75 years patency rates were 78%, 62%, and 62% for distal and 87%, 67%, and 67% for middle-arm fistula. Among diabetic subjects patency rates were 81%, 58%, and 58% for middle-arm and 65%, 57%, and 57% for distal fistula at 12, 48, and 60 months (P NS) respectively.

Conclusions

A middle-arm fistula is as safe as a distal fistula among dialyzed patients, even diabetic and elderly. This could be considered a reliable option to expand native accesses.
Does skeletal anatomy reflect adaptation to locomotor patterns? cortical and trabecular architecture in human and nonhuman anthropoids
Authors: Shaw Colin N. , Ryan Timothy M.
Published: November 2011

Although the correspondence between habitual activity and diaphyseal cortical bone morphology has been demonstrated for the fore‐ and hind‐limb long bones of primates, the relationship between trabecular bone architecture and locomotor behavior is less certain. If sub‐articular trabecular and diaphyseal cortical bone morphology reflects locomotor patterns, this correspondence would be a valuable tool with which to interpret morphological variation in the skeletal and fossil record. To assess this relationship, high‐resolution computed tomography images from both the humeral and femoral head and midshaft of 112 individuals from eight anthropoid genera (Alouatta, Homo, Macaca, Pan, Papio, Pongo, Trachypithecus, and Symphalangus) were analyzed. Within‐bone (sub‐articular trabeculae vs. mid‐diaphysis), between‐bone (forelimb vs. hind limb), and among‐taxa relative distributions (femoral:humeral) were compared. Three conclusions are evident: (1) Correlations exists between humeral head sub‐articular trabecular bone architecture and mid‐humerus diaphyseal bone properties; this was not the case in the femur. (2) In contrast to comparisons of inter‐limb diaphyseal bone robusticity, among all species femoral head trabecular bone architecture is significantly more substantial (i.e., higher values for mechanically relevant trabecular bone architectural features) than humeral head trabecular bone architecture. (3) Interspecific comparisons of femoral morphology relative to humeral morphology reveal an osteological “locomotor signal” indicative of differential use of the forelimb and hind limb within mid‐diaphysis cortical bone geometry, but not within sub‐articular trabecular bone architecture. Am J Phys Anthropol 147:187–200, 2012. © 2011 Wiley Periodicals, Inc.
The use of biocultural data in interpreting sex differences in body proportions among rural amazonians
Authors: Vercellotti Giuseppe , Piperata Barbara A.
Published: November 2011

Variation in height and body proportions is relatively well‐understood at the inter‐population level, but less is known about intra‐population variation. This study explores intra‐population variation in body proportions among 172 (88 female; 84 male) adult rural Amazonians. We test the hypotheses that: (1) stunting is associated with changes in proportions and fatness; (2) the sexes express different proportions in response to similar environmental stress; and (3) female growth is negatively affected by the costs of reproduction. We examined height, sitting height, and total leg length in subsamples based on sex and nutritional status (stunted/nonstunted) in relation to biocultural factors including access to food and healthcare and female reproductive history parameters. Differences in proportions were examined using the Quick‐Test (Tsutakawa and Hewett: Biometrics 33 (1977) 215–219); correlation analyses were used to detect associations between anthropometric data and body fatness, and female reproductive history parameters. We found significantly higher rates of stunting among females (X2 = 5.31; P = 0.02; RR = 1.4). Stunted individuals exhibited relatively shorter legs than nonstunted individuals (P = 0.02), although this was not found in within‐sex analyses. A significant negative correlation was found between leg length index and fatness (P < 0.01). Lastly, females exhibited relatively shorter legs than males (P = 0.0003) and, among females, height and leg length were significantly positively correlated with age‐at‐first‐birth (P < 0.02) suggesting that adolescent pregnancy may negatively affect growth in this population. Our findings provide insights for the study of intra‐population variation in body proportions and highlight the importance of biocultural data in interpreting the pattern of variation observed in living and past populations. Am J Phys Anthropol 2012. © 2011 Wiley Periodicals, Inc.
Predictors of highly prevalent brain ischemia in intracerebral hemorrhage
Authors: Menon Ravi S. , Burgess Richard E. , Wing Jeffrey J. , Gibbons M. Christopher , Shara Nawar M. , Fernandez Stephen , Jayam‐Trouth Annapurni , German Laura , Sobotka Ian , Edwards Dorothy , Kidwell Chelsea S.
Published: November 2011

Objective:

This study was undertaken to determine the prevalence, characteristics, risk factors, and temporal profile of concurrent ischemic lesions in patients with acute primary intracerebral hemorrhage (ICH).

Methods:

Patients were recruited within a prospective, longitudinal, magnetic resonance imaging (MRI)‐based study of primary ICH. Clinical, demographic, and MRI data were collected on all subjects at baseline and 1 month.

Results:

Of the 138 patients enrolled, mean age was 59 years, 54% were male, 73% were black, and 84% had a history of hypertension. At baseline, ischemic lesions on diffusion‐weighted imaging (DWI) were found in 35% of patients. At 1 month, lesions were present in 27%, and of these lesions, 83% were new and not present at baseline. ICH volume (p = 0.025), intraventricular hemorrhage (p = 0.019), presence of microbleeds (p = 0.024), and large, early reductions in mean arterial pressure (p = 0.003) were independent predictors of baseline DWI lesions. A multivariate logistical model predicting the presence of 1‐month DWI lesions included history of any prior stroke (p = 0.012), presence of 1 or more microbleeds (p = 0.04), black race (p = 0.641), and presence of a DWI lesion at baseline (p = 0.007).

Interpretation:

This study demonstrates that >⅓ of patients with primary ICH have active cerebral ischemia at baseline remote from the index hematoma, and ¼ of patients experience ongoing, acute ischemic events at 1 month. Multivariate analyses implicate blood pressure reductions in the setting of an active vasculopathy as a potential underlying mechanism. Further studies are needed to determine the impact of these lesions on outcome and optimal management strategies to arrest vascular damage. Ann Neurol 2012;71:199–205
Potassium channel complex autoimmunity induced by inhaled brain tissue aerosol
Authors: Meeusen Jeffrey W. , Klein Christopher J. , Pirko Istvan , Haselkorn Keegan E. , Kryzer Thomas J. , Pittock Sean J. , Lachance Daniel H. , Dyck P. James , Lennon Vanda A.
Published: November 2011

Objective:

To test the hypothesis that autoimmunity induced by inhalation of aerosolized brain tissue caused outbreaks of sensory‐predominant polyradiculoneuropathy among swine abattoir employees in the Midwestern United States.

Methods:

Mice were exposed intranasally, 5 days per week, to liquefied brain tissue. Serum from exposed mice, patients, and unaffected abattoir employees were analyzed for clinically pertinent neural autoantibodies.

Results:

Patients, coworkers, and mice exposed to liquefied brain tissue had an autoantibody profile dominated by neural cation channel immunoglobulin Gs (IgGs). The most compelling link between patients and exposed mice was magnetic resonance imaging (MRI) evidence of grossly swollen spinal nerve roots. Autoantibody responses in patients and mice were dose‐dependent and declined after antigen exposure ceased. Autoantibodies detected most frequently, and at high levels, bound to detergent‐solubilized macromolecular complexes containing neuronal voltage‐gated potassium channels ligated with a high affinity Kv1 channel antagonist, 125I‐α‐dendrotoxin. Exposed mice exhibited a behavioral phenotype consistent with potassium channel dysfunction recognized in drosophila with mutant (“shaker”) channels: reduced sensitivity to isoflurane‐induced anesthesia. Pathological and electrophysiological findings in patients supported peripheral nerve hyperexcitability over destructive axonal loss. The pain‐predominant symptoms were consistent with sensory nerve hyperexcitability.

Interpretation:

Our observations establish that inhaled neural antigens readily induce neurological autoimmunity and identify voltage‐gated potassium channel complexes as a major immunogen. ANN NEUROL 2012;
Late motor decline after accomplished remyelination: Impact for progressive multiple sclerosis
Authors: Manrique‐Hoyos Natalia , Jürgens Tanja , Grønborg Mads , Kreutzfeldt Mario , Schedensack Mariann , Kuhlmann Tanja , Schrick Christina , Brück Wolfgang , Urlaub Henning , Simons Mikael , Merkler Doron
Published: November 2011

Objective:

To investigate the impact of single or repeated episodes of reversible demyelination on long‐term locomotor performance and neuroaxonal integrity, and to analyze the myelin proteome after remyelination and during aging.

Methods:

Long‐term locomotor performance of previously cuprizone‐treated animals was monitored using the motor skill sequence (MOSS). Quantitative analysis of myelin proteome and histopathological analysis of neuronal/axonal integrity was performed after successful remyelination. Histopathological findings observed in experimental chronic remyelinated lesions were verified in chronic remyelinated lesions from multiple sclerosis (MS) patients.

Results:

Following cessation of cuprizone treatment, animals showed an initial recovery of locomotor performance. However, long after remyelination was completed (approximately 6 months after the last demyelinating episode), locomotor performance again declined in remyelinated animals as compared to age‐matched controls. This functional decline was accompanied by brain atrophy and callosal axonal loss. Furthermore, the number of acutely damaged amyloid precursor protein–positive (APP+) axons was still significantly elevated in long‐term remyelinated animals as compared to age‐matched controls. Confocal analysis revealed that a substantial proportion of these APP+ spheroids were ensheathed by myelin, a finding that was confirmed in the chronic remyelinated lesions of MS patients. Moreover, quantitative analysis of myelin proteome revealed that remyelinated myelin displays alterations in composition that are in some aspects similar to the myelin of older animals.

Interpretation:

We propose that even after completed remyelination, axonal degeneration continues to progress at a low level, accumulating over time, and that once a threshold is passed axonal degeneration can become functionally apparent in the long‐term. The presented model thus mimics some of the aspects of axonal degeneration in chronic progressive MS. ANN NEUROL 2012;71:227–244
ESI‐MS/MS stability‐indicating bioanalytical method development and validation for simultaneous estimation of donepezil, 5‐desmethyl donepezil and 6‐desmethyl donepezil in human plasma
Authors: Khuroo Arshad H. , Gurule Sanjay J. , Monif Tausif , Goswami Dipanjan , Saha Arabinda , Singh Santosh K.
Published: November 2011

A bioanalytical method was developed and validated to estimate donepezil, 6‐desmethyl donepezil and 5‐desmethyl donepezil simultaneously in human plasma using galantamine as an internal standard (IS). The chromatographic separation was achieved on a reverse‐phase XTerra RP (150 × 4.6 mm, 5 µm) column without affecting recovery (mean recovery > 60% with CV < 10%) for all analytes. ESI‐MS/MS multiple reaction monitoring in positive polarity was used to detect mass pairs for donepezil (m/z 380.3 → 91.3), 6‐desmethyl donepezil (m/z 366.4 → 91.3), 5‐desmethyl donepezil (m/z 366.4 → 91.3) and galantamine m/z (288.1 → 213.0). The linearity was established over a dynamic range of 0.339–51.870, 0.100–15.380 and 0.103–15.763 ng/mL for donepezil, 6‐desmethyl donepezil and 5‐desmethyl donepezil, respectively. The current method shows that minimal conversion of labile metabolites to parent donepezil in plasma as stability was successfully achieved for 211 days at −15 °C storage temperature. The method was successfully applied to a clinical study after administration of 10 mg donepezil tablets to healthy male Indian volunteers. Copyright © 2011 John Wiley & Sons, Ltd.
A novel microplate‐based HPLC‐fluorescence assay for determination of NADPH‐cytochrome P450 reductase activity
Authors: Erban Tomas , Poltronieri Palmiro , Stara Jitka
Published: November 2011

A 96‐well microplate‐based HPLC endpoint assay is described for the determination of NADPH‐cytochrome P450 reductase (CPR) activity. Novel sampling of NADPH into microplates was optimized. Separation was performed on a Zorbax Eclipse XDB‐C18 analytical 4.6 × 150 mm, 5 µm column. To validate the method, recombinant human NADPH‐P450 reductase and microsomes with cytochrome P450 CYP1A1 were used. The mobile phase consisted of 80% acetonitrile and 20% water at a flow‐rate of 0.8 mL/min. The CPR activity was quantified using NADPH fluorescence at λEx = 340 nm and λEm = 450 nm. Enzymatic activity was directly proportional to the decrease in NADPH fluorescence. This analytical process enables a highly sensitive endpoint determination for reductase activity in vitro and monitoring of the consumption of NADPH in enzymatic reactions. The method avoids the use of substrates and of organic solvents that may affect CPR and cytochrome P450 activity. In the reaction, molecular oxygen served as a proton source. The method can substitute spectrophotometric detection methods for its accuracy, high reproducibility (~100%) and sensitivity. The lower limit of detection, shown using the Agilent 1200 aparatus, is in the 250 nmol range. In addition, using this method it is possible to set up reactions in a high‐throughput format. Copyright © 2011 John Wiley & Sons, Ltd.
Reporting of radiation exposure in contemporary interventional cardiology trials
Authors: Vargas Alejandro , Shroff Adhir R. , Vidovich Mladen I.
Published: November 2011

Objectives: To determine reporting of radiation exposure in contemporary interventional cardiology randomized trials published in leading journals. Background: Interventional cardiology procedures are a significant source of ionizing radiation, which can have detrimental effects on both patients and medical personnel. Methods: The EuroIntervention 2010 supplement served as a source of randomized trials in interventional cardiology published in scientific literature from 2000 to 2010. Results: Of all the trials in the supplement, 204 represented original research and were examined for reporting of radiation dose and fluoroscopy times. Only eight trials (3.92%) reported either radiation exposure or fluoroscopy time, covering 16,563 patients (4.55% of the total patient population of 363,727). All of these trials were published after 2006. The average fluoroscopy time reported in seven trials was 13.6 min and the mean radiation dose reported in three trials was 58.67 Gy cm2. Conclusions: Radiation exposure is not consistently reported in contemporary interventional cardiology trials. Even when reporting occurs, trials may not report detailed data such as radiation dose, radiation exposure time, or fluoroscopy time. Although reporting of radiation exposure has not been a requirement in research studies, efforts by professional societies and regulatory authorities toward standardized reporting should aid clinicians in making a more informed decision on specific interventional procedures and devices. © 2012 Wiley Periodicals, Inc.
Predictors of treatment in acute coronary syndromes in the elderly
Authors: Rittger Harald , Schnupp Steffen , Sinha Anil‐Martin , Breithardt Ole‐Alexander , Schmidt Martin , Zimmermann Stefan , Mahnkopf Christian , Brachmann Johannes , Rieber Johannes
Published: November 2011

Background: Management of elderly patients with acute coronary syndromes (ACS) is not standardized and physicians discretion for invasive versus conservative strategies lacks sufficient evidence. The purpose of this analysis was, therefore, to evaluate treatment strategies and outcomes of elderly patients with ACS and to highlight reasons for the treatment decision in a consecutive series of elderly patients. Methods: This is a retrospective analysis of 1,001 elderly patients (>75 years) presenting with ACS. Patients were identified on the basis of their final discharge diagnosis. Baseline data, past medical history, cardiac and noncardiac concomitant diseases, treatment strategy, and adverse outcomes were evaluated, using patient's charts. Various co‐variates were used to determine the association or predictive value of these co‐variates to the invasive versus conservative management of the subjects. Thirty‐day mortality and long‐term survival were assessed either directly or in discharged patients via telephone interview with the patients, the patients' relatives or the primary care physicians. Results: A total of 776 (77.5%) patients were treated invasively and 225 (22.5%) conservatively. Logistic regression analysis revealed that patients with advanced age, Killip class > II, pre‐existing coronary artery disease, prior stroke, pre‐existing renal failure, obesity, non‐ST‐elevation myocardial infarction, prior ACS, and the presence of supraventricular arrhythmias were significantly more likely to undergo conservative treatment. In‐hospital mortality was significantly higher in conservatively treated patients (P < 0.001). Conclusion: In this retrospective analysis, we identified age as the main predictor for a conservative treatment strategy in elderly patients, albeit an invasive strategy was associated with a significantly better outcome. © 2012 Wiley Periodicals, Inc.
Transcatheter aortic valve implantation for treatment of failing homograft with preexisting mechanical mitral prosthesis
Authors: Attia Rizwan , Bapat Vinnie
Published: November 2011

Transcatheter aortic valve implantation is increasingly used to treat bioprosthetic degeneration. Valve‐in‐valve technique has been performed successfully to treat homograft, stentless, and stented bioprosthetic dysfunction. The presence of a prosthesis in the mitral position can make the transcatheter aortic valve implantation procedure challenging due to proximity of the mitral and aortic annuli. We describe the case of a 66‐year‐old who underwent the first successful implantation of Edwards Sapien device in a failing homograft in the presence of a mechanical mitral valve prosthesis. © 2013 Wiley Periodicals, Inc.
Incidence and angiographic characteristics of patients With apical ballooning syndrome (takotsubo/stress cardiomyopathy) in the HORIZONS‐AMI trial
Authors: Prasad Abhiram , Dangas George , Srinivasan Manivannan , Yu Jennifer , Gersh Bernard J. , Mehran Roxana , Stone Gregg W.
Published: November 2011

Objectives: To determine the incidence, clinical characteristics, and the coronary angiographic features of patients with apical ballooning syndrome (ABS) among those recruited into a large, prospective, international, multicenter trial. Background: ABS is an important entity in the differential diagnosis of ST‐elevation myocardial infarction (STEMI). Current data regarding ABS are limited to single center registries. Methods: Patients with ABS were identified, based on the Mayo Clinic diagnostic criteria, from those enrolled into the HORIZONS‐AMI trial. Quantitative angiography was performed by a core laboratory to identify the frequency and severity of coronary artery disease. Results: Among the 2,648 patients who had left ventriculography in addition to coronary angiography, 12 patients were identified with ABS. All patients were female and they were compared to the remaining 571 female patients with STEMI. Compared with patients with STEMI (97.9% of our cohort), patients with ABS (2.1%) had a lower prevalence (42% vs. 100%, P < 0.05) and severity (number of plaques measuring >30% diameter stenosis per patient: 0.58 ± 0.90 vs. 4.13 ± 2.68, P < 0.0001) of coronary artery disease. There were no in‐hospital deaths or major adverse cardiovascular events (MACE) in the ABS group vs. 2.1% and 3.7% respectively in the STEMI group, nor at 2‐year follow up (death: 0% vs. 5.5%, MACE: 0% vs. 19.4%), but these differences were not statistically significant. Conclusions: In HORIZONS‐AMI, ABS was identified exclusively in women (2.1% of female patients, 0.5% of all patients) and MACE were absent in this uncommon but important group of patients. Coronary artery disease was often present in patients with ABS, but its prevalence and severity was significantly less compared with STEMI patients. © 2011 Wiley Periodicals, Inc.
Biodiesel Production from the Lipid of Wastewater Sludge Using an Acidic Heterogeneous Catalyst
Authors: Siddiquee M. N. , Kazemian H. , Rohani S.
Published: November 2011

The production of biodiesel from the lipid of wastewater sludge was studied using SBA‐15 impregnated with the heteropolyacid H3PO4·12WO3·xH2O (PW12) as a mesoporous heterogeneous catalyst. X‐ray diffraction, Brunauer‐Emmett‐Teller surface area, thermalgravimetric analysis, and scanning electron microscopy were applied to characterize the prepared catalysts. Catalytic performances were evaluated in a microreactor setup under different experimental conditions. The biodiesel yield for a sample impregnated with 15 % PW12 was 30.14 wt‐% at a temperature of 135 °C and a pressure of 135 psi for 3 h reaction time.
Cold Flow Model Study of an Oxyfuel Combustion Pilot Plant
Authors: Guío‐Pérez D. C. , Tondl G. , Höltl W. , Pröll T. , Hofbauer H.
Published: November 2011

The fluid‐dynamic behavior of a circulating fluidized bed pilot plant for oxyfuel combustion was studied in a cold flow model, down‐scaled using Glicksman's criteria. Pressures along the unit and the global circulation rate were used for characterization. The analysis of five operating parameters and their influence on the system was carried out; namely, total solids inventory and the air velocity of primary, secondary, loop seal and support fluidizations. The cold flow model study shows that the reactor design allows stable operation at a wide range of fluidization rates, with results that agree well with previous observations described in the literature.
Synthesis and Properties of Hybrid Porphyrin Tapes
Authors: Tanaka Takayuki , Lee Byung Sun , Aratani Naoki , Yoon Min‐Chul , Kim Dongho , Osuka Atsuhiro
Published: November 2011

Hybrid porphyrin tapes 3 and 4, consisting of a mixture of 3,5‐di‐tert‐butylphenyl‐substituted donor‐type ZnII–porphyrins and pentafluorophenyl‐substituted acceptor‐type ZnII–porphyrins, were prepared by a synthetic route involving cross‐condensation reaction of a NiII–porphyrinyldipyrromethane and pentafluorophenyldipyrromethane with pentafluorobenzaldehyde followed by appropriate demetalation, remetalation, and oxidative ring‐closure reaction. The NiII‐substituted porphyrin tapes 5 (Ni‐Zn‐Ni) and 6 (Ni‐H2‐Ni) were also prepared through similar routes. The hybrid porphyrin tapes 3 and 4 are more soluble and more stable than normal porphyrin tapes 1 and 2 consisting of only donor‐type ZnII–porphyrins. The solid‐state and crystal packing structures of 3, 4, and 5 were elucidated by single‐crystal X‐ray diffraction analysis. Singly meso–meso‐linked hybrid porphyrin arrays 12 and 14 exhibit redox potentials that roughly correspond to each constituent porphyrin segments, while the redox potentials of the hybrid porphyrin tapes 3 and 4 are positively shifted as a whole. The two‐photon absorption (TPA) values of 1–6 were measured by using a wavelength‐scanning open aperture Z‐scan method and found to be 1900, 21 000, 2200, 27 000, 24 000, and 26 000 GM, respectively. These results illustrate an important effect of elongation of π‐electron conjugation for the enhancement of TPA values. The hybrid porphyrin tapes show slightly larger TPA values than the parent ones.
Developmental origins and architecture of Drosophila leg motoneurons
Authors: Brierley D.J. , Rathore K. , VijayRaghavan K. , Williams D.W.
Published: November 2011

Motoneurons are key points of convergence within motor networks, acting as the “output channels” that directly control sets of muscles to maintain posture and generate movement. Here we use genetic mosaic techniques to reveal the origins and architecture of the leg motoneurons of Drosophila. We show that a small number of leg motoneurons are born in the embryo but most are generated during larval life. These postembryonic leg motoneurons are produced by five neuroblasts per hemineuromere, and each lineage generates stereotyped lineage‐specific projection patterns. Two of these postembryonic neuroblasts generate solely motoneurons that are the bulk of the leg motoneurons. Within the largest lineage, lineage 15, we see distinct birth‐order differences in projection patterns. A comparison of the central projections of leg motoneurons and the muscles they innervate reveals a stereotyped architecture and the existence of a myotopic map. Timeline analysis of axonal outgrowth reveals that leg motoneurons reach their sites of terminal arborization in the leg at the time when their dendrites are elaborating their subtype‐specific shapes. Our findings provide a comprehensive description of the origin, development, and architecture of leg motoneurons that will aid future studies exploring the link between the assembly and organization of connectivity within the leg motor system of Drosophila. J. Comp. Neurol. 520:1629–1649, 2012. © 2011 Wiley Periodicals, Inc.
Two populations of corticothalamic and interareal corticocortical cells in the subgranular layers of the mouse primary sensory cortices
Authors: Petrof Iraklis , Viaene Angela N. , Sherman S. Murray
Published: November 2011

The subgranular layers (layers 5 and 6) of primary sensory cortex provide corticofugal output to thalamus and they also project to the appropriate secondary sensory cortices. Here we injected two combinations of different color retrograde fluorescent markers in the thalamic and cortical targets of these layers from the three primary sensory cortices (somatosensory, auditory, and visual) in mice to examine the degree of overlap between corticothalamic and interareal corticocortical cells in the subgranular layers. We found that, for all three primary sensory cortices, double‐labeled cells were extremely rare, indicating that corticothalamic and interareal corticocortical cells in the subgranular layers represent largely independent populations. J. Comp. Neurol. 520:1678–1686, 2012. © 2011 Wiley Periodicals, Inc.
Epha4 controls the midline crossing and contralateral axonal projections of inferior olive neurons
Authors: Hashimoto Mitsuhiro , Ito Rie , Kitamura Naohito , Namba Kazunori , Hisano Yasuko
Published: November 2011

The guidance of axonal projections to ipsilateral and contralateral regions is essential for integration of bilateral sensory information and coordination of movement. In the development of olivocerebellar projections, newborn neurons of inferior olivary (IO) nuclei ventrally migrate from the hindbrain rhombic lip to the floor plate (FP). The cell bodies of IO neurons cannot cross the FP but their axons can, and thus IO neurons project their axons only to the contralateral cerebellar cortex. The molecular mechanisms determining the contralateral axonal projections of IO neurons, however, are obscure. The IO neurons and their axons express EphA4, whereas the FP expresses an EphA4 ligand, EphrinB3, from embryonic day 12.5. Therefore, we tested whether EphA4‐deficient mice (EphA4−/−) would show impairment in the development of olivocerebellar projections. We found that, in EphA4−/− embryos, some of the IO neurons projected their axons to the ipsilateral cerebellar cortex because the cell bodies of the IO neurons abnormally crossed the FP. Furthermore, even in adults, EphA4−/− cerebella were bilaterally innervated by unilateral IO subnuclei. These observations indicate that EphA4 is involved in the contralateral axonal projections of IO neurons by preventing their cell bodies from crossing the midline FP. J. Comp. Neurol. 520:1702–1720, 2012. © 2011 Wiley Periodicals, Inc.
Second‐order input to the medial amygdala from olfactory sensory neurons expressing the transduction channel TRPM5
Authors: Thompson John A. , Salcedo Ernesto , Restrepo Diego , Finger Thomas E.
Published: November 2011

Recent anatomical tracing experiments in rodents have established that a subset of mitral cells in the main olfactory bulb (MOB) projects directly to the medial amygdala (MeA), traditionally considered a target of the accessory olfactory bulb. Neurons that project from the MOB to the MeA also show activation in response to conspecific (opposite sex) volatile urine exposure, establishing a direct role of the MOB in semiochemical processing. In addition, olfactory sensory neurons (OSNs) that express the transient receptor potential M5 (TRPM5) channel innervate a subset of glomeruli that respond to putative semiochemical stimuli. In this study, we examined whether the subset of glomeruli targeted by TRPM5‐expressing OSNs is innervated by the population of mitral cells that projects to the MeA. We injected the retrograde tracer cholera toxin B (CTB) into the MeA of mice in which the TRPM5 promoter drives green fluorescent protein (GFP). We found overlapping clusters of CTB‐labeled mitral cell dendritic branches (CTB+) in TRPM5‐GFP+ glomeruli at significantly greater frequency than expected by chance. Despite the significant degree of colocalization, some amygdalopetal mitral cells extended dendrites to non‐TRPM5‐GFP glomeruli and vice versa, suggesting that, although significant overlapping glomerular innervation is observed between these two features, it is not absolute J. Comp. Neurol. 520:1819–1830, 2012. © 2011 Wiley Periodicals, Inc.
SNARE protein expression and localization in human cytotoxic T lymphocytes
Authors: Pattu Varsha , Qu Bin , Schwarz Eva C. , Strauß Bettina , Weins Lisa , Bhat Shruthi S. , Halimani Mahantappa , Marshall Misty , Rettig Jens , Hoth Markus
Published: November 2011

The major function of cytotoxic T lymphocytes (CTLs) is to eliminate pathogen‐infected and tumorigenic cells. This is mediated mainly through the exocytosis of lytic granules (LGs) containing cytotoxic components, such as perforin and granzymes at the immunological synapse (IS). The soluble NSF attachment receptor (SNARE) protein isoforms are well known to be required for vesicle exocytosis in neuronal synapses, but their potential function in CTLs is only partly understood. Here, we examined the expression of SNARE proteins before and after the activation of primary human CD8+ T cells and determined their co‐localization with LGs and CD3 after IS formation with target cells. We found that several key SNARE proteins in neuronal cells were not expressed in CTLs, such as syntaxin1B2 and SNAP‐25. Vti1b, Stx8 and Stx16 had the highest degrees of co‐localization with LGs while Stx3, Stx4, Stx6, Stx7, Stx8, Stx13, Vti1b, VAMP3 and VAMP4 co‐localized with CD3. Our data provide the first complete expression profile and localization of SNAREs in primary human CD8+ T cells, laying the groundwork for further understanding their potential role in T‐cell function.
Single‐Use Sensor Platforms Based on Carbon Nanotubes for Electrochemical Detection of DNA Hybridization Related to Microcystis spp.
Authors: Erdem Arzum , Karadeniz Hakan , Canavar Pembe Ece , Congur Gulsah
Published: November 2011

The electrochemical monitoring of (i) label‐free and (ii) indicator based DNA hybridization related to Microcystis spp. (MYC) DNA was explored in this study via multiwalled carbon nanotube (MWCNT) based screen printed graphite electrodes (SPEs). The effect of CNT modification onto SPE was firstly investigated by measuring the oxidation signals of guanine and adenine before/after DNA immobilization onto the surfaces of bare SPE, MWCNT‐SPE and SWCNT‐SPE in combination with differential pulse voltammetry. MYC‐DNA hybridization was monitored by following two procedures and measuring the guanine oxidation signal and the reduction signal of cobalt‐phenanthroline Co(phen)33+. Voltammetric results were complemented with electrochemical impedance spectroscopy (EIS).
A Simple Strategy for Simultaneous Determination of Paracetamol and Caffeine Using Flow Injection Analysis with Multiple Pulse Amperometric Detection
Authors: Silva Wesley C. , Pereira Polyana F. , Marra Mariana C. , Gimenes Denise T. , Cunha Rafael R. , da Silva Rodrigo A. B. , Munoz Rodrigo A. A. , Richter Eduardo M.
Published: November 2011

In this work, we report a simple and novel strategy for simultaneous analysis using flow injection analysis with multiple pulse amperometric (FIA‐MPA) detection. The proposed strategy was successfully used for simultaneous determination of paracetamol and caffeine (model analytes) in pharmaceutical formulations. A sequence of potential pulses (waveform) was selected in such a way that PA is selectively oxidized at E1 (+1.20 V/50 ms) and both compounds (PA+CA) are simultaneously oxidized at E2 (+1.55 V/50 ms); hence, current subtraction (using a correction factor) can be used for the selective determination of CA. The proposed FIA method is simple, cheap, fast (140 injections h−1), and present selectivity for the determination of both compounds in pharmaceutical samples, with results similar to those obtained by HPLC at a 95 % confidence level.
Noncovalent Assembly of Picket‐Fence Porphyrin on Carbon Nanotubes as Effective Peroxidase‐Like Catalysts for Detection of Hydrogen Peroxide in Beverages
Authors: Li Xiao‐Rong , Wang Bo , Xu Jing‐Juan , Chen Hong‐Yuan
Published: November 2011

A newly developed electrochemical sensor for determination of hydrogen peroxide (H2O2) in beverages using a water‐insoluble picket‐fence porphyrin (FeTpivPP) functionalized multiwalled carbon nanotubes (MWNTs) is demonstrated. Introduction of FeTpivPP on MWNTs led to enhanced electron transfer. As a new platform in electrochemical analysis, the resultant sensor showed excellent electrocatalytic activity toward the reduction of H2O2 due to the synergic effect between MWNTs and FeTpivPP, thus leading to highly sensitive amperometric sensing of H2O2 with a detection limit of 0.05 µmol L−1. The developed method is successfully used to detect H2O2 in beverages and shows great promise for routine sensing applications.
Glutathione level and genotoxicity in human oral keratinocytes exposed to TEGDMA
Authors: Volk Joachim , Leyhausen Gabriele , Geurtsen Werner
Published: November 2011

Triethylene‐glycol dimethacrylate (TEGDMA) is an important matrix comonomer used in many resin‐modified dental materials. As the monomer‐polymer conversion of these biomaterials is up to 80% at best, TEGDMA may leach into the oral cavity and the pulp in millimolar concentrations. Objective of this study was to evaluate whether TEGDMA is genotoxic in immortalized human oral keratinocytes (OKF6/TERT2), for example, due to formation of oxidative DNA‐lesions. OKF6‐TERT2 cells were exposed to TEGDMA at concentrations ranging from 0.5 mM to 5.0 mM. Cell viability was analyzed by the fluorescent probe propidium iodide (PI), intracellular levels of reactive oxygen species (ROS) were measured by 2′,7′‐dichlorofluorescein diacetate, whereas glutathione concentrations (GSH) were read using monobromobimane. Genotoxicity was determined quantitatively by the alkaline comet assay. To explore the presence of oxidized bases that could be produced by oxidative events during short‐term treatment with TEGDMA, the 8‐hydroxyguanine DNA‐glycosylase 1 (hOGG1)‐modified comet assay was used. TEGDMA induced an early and rapid GSH‐depletion in a concentration‐dependent manner (p < 0.05). A total of 5 mM TEGDMA reduced GSH to 57.8% ± 8.6% of control values already after 30 min. There was no significant reduction in cell viability during 6 h of incubation, and only moderate ROS‐formation was detected after 4 h of treatment with TEGDMA. But after 24 h, TEGDMA‐concentrations of ≥2.5 mM induced a significant reduction of total cell numbers and cells' viability. Furthermore, TEGDMA caused a concentration‐dependent DNA damage in OKF6/TERT2 cultures, which was not associated with a detectable formation of 8‐hydroxy‐2'‐deoxyguanosine (8‐OHdG) in the cellular genome. In conclusion, our results show that TEGDMA influences the intracellular redox metabolism and may exhibit pronounced cyto‐ and genotoxic effects in human immortalized oral keratinocytes. However, it may be concluded that oxidative stress is not causative for TEGDMA‐dependent genotoxicity in these cells. © 2011 Wiley Periodicals, Inc. J Biomed Mater Res Part B: Appl Biomater 100B: 391–399, 2012.
In vitro degradation behavior and bioactivity of magnesium‐Bioglass® composites for orthopedic applications
Authors: Huan Zhiguang , Leeflang Sander , Zhou Jie , Zhai Wanyin , Chang Jiang , Duszczyk Jurek
Published: November 2011

To improve the bioactivity and degradation behavior of biodegradable magnesium, biodegradable metal matrix composites with the ZK30 magnesium alloy as the matrix and bioactive glass (BG, 45S5) as the reinforcement were prepared. The microstructures of the ZK30‐BG composites showed homogeneous dispersion of BG particles throughout the matrix. XRD and EDX analyses confirmed the retention of the morphological characteristics and composition of BG particles in the composites. Immersion tests in the minimum essential medium with Earle's balanced salts at 37°C showed that the composites with 5 and 10% BG had lower rates of degradation and hydrogen evolution than the matrix alloy. In addition, the tests confirmed that the composites possessed an enhanced ability to induce calcium and phosphate ion deposition on sample surfaces during degradation, suggesting accelerated surface mineralization that would lead to improved bioactivity when compared with the matrix alloy. In vitro cytotoxicity tests showed that the ionic products of the composites formed during degradation possessed a superior ability to support the survival, proliferation, and osteoblastic differentiation of bone marrow stromal cells to those of the ZK30 alloy. The ZK30‐BG composites with enhanced bioactivity and reduced degradation rate could be promising biodegradable materials for orthopedic implants. © 2011 Wiley Periodicals, Inc. J Biomed Mater Res Part B: Appl Biomater 100B: 437–446, 2012.
The influence of grain size on low‐temperature degradation of dental zirconia
Authors: Hallmann Lubica , Mehl Albert , Ulmer Peter , Reusser Eric , Stadler Johannes , Zenobi Renato , Stawarczyk Bogna , Özcan Mutlu , Hämmerle Christoph H. F.
Published: November 2011

The purpose of this study was to evaluate the influence of grain size and air abrasion on low‐temperature degradation (LTD) of yttria stabilized tetragonal zirconia polycrystalline (Y‐TZP). Disc‐shaped specimens were sintered at 1350, 1450, and 1600°C. Air abrasion was performed with different abrasive particles. The specimens were stored for 2 h at 134°C under 2.3 bar water vapor pressure. All specimens were characterized by X‐ray powder diffraction analysis (XRD), Raman spectroscopy, X‐ray photoelectron spectroscopy (XPS), atomic force microscopy (AFM), and field emission scanning electron microscopy (FESEM). Y‐TZP sintered at a temperature of 1350°C did not undergo the t–m phase transformation during accelerated aging. The diffusion‐controlled t–m phase transformation initiated with the specimens sintered at 1450°C. This transformation was remarkable for the specimens sintered at 1600°C. X‐ray photoelectron spectroscopy (XPS) measurements did not confirm the generation of Zr‐OH and Y‐OH bonds. No increase of yttrium concentration on the grain boundaries of Y‐TZP was detected, which could be responsible for the destabilization of dental zirconia ceramics. A slight increase of diffusion‐controlled t–m phase transformations was observed for all abraded specimens sintered at 1350 and 1450°C. The size of abrasive particles did not play a crucial role on LTD of Y‐TZP. The retardation of diffusion‐controlled t–m phase transformation was evident for all abraded specimens sintered at 1600°C by comparison to non‐abraded specimens. Conclusion: The LTD of Y‐TZP can be suppressed when the sintering temperature is set between 1350 and 1450°C. © 2011 Wiley Periodicals, Inc. J Biomed Mater Res Part B: Appl Biomater 100B: 447–456, 2012.
Path‐integral calculations of heavy atom kinetic isotope effects in condensed phase reactions using higher‐order trotter factorizations
Authors: Vardi‐Kilshtain Alexandra , Azuri Asaf , Major Dan Thomas
Published: November 2011

A convenient approach to compute kinetic isotope effects (KIEs) in condensed phase chemical reactions is via path integrals (PIs). Usually, the primitive approximation is used in PI simulations, although such quantum simulations are computationally demanding. The efficiency of PI simulations may be greatly improved, if higher‐order Trotter factorizations of the density matrix operator are used. In this study, we use a higher‐order PI method, in conjunction with mass‐perturbation, to compute heavy‐atom KIE in the decarboxylation of orotic acid in explicit sulfolane solvent. The results are in good agreement with experiment and show that the mass‐perturbation higher‐order Trotter factorization provides a practical approach for computing condensed phase heavy‐atom KIE. © 2011 Wiley Periodicals, Inc. J Comput Chem, 2012
Theoretical calculation about the valence and rydberg excited states of hydrogen cyanide
Authors: Li Bu‐Tong , Li Lu‐Lin , Wu Hai‐Shun
Published: November 2011

The singlet and triplet excited states of hydrogen cyanide have been computed by using the complete active space self‐consistent field and completed active space second order perturbation methods with the atomic natural orbital (ANO‐L) basis set. Through calculations of vertical excitation energies, we have probed the transitions from ground state to valence excited states, and further extensions to the Rydberg states are achieved by adding 1s1p1d Rydberg orbitals into the ANO‐L basis set. Four singlet and nine triplet excited states have been optimized. The computed adiabatic energies and the vertical transition energies agree well with the available experimental data and the inconsistencies with the available theoretical reports are discussed in detail. © 2011 Wiley Periodicals, Inc. J Comput Chem, 2011