bluuebunny/crossref_metadata_2025 huggingface dataset:
Morphology of the quadrate in the Eocene anseriform Presbyornis and extant galloanserine birds
Authors: Elzanowski Andrzej , Stidham Thomas A.
Published: October 2009

Despite the notoriety, phylogenetic significance, and large number of available specimens of Presbyornis, its cranial anatomy has never been studied in detail, and its quadrate has been partly misinterpreted. We studied five quadrates of Presbyornis that reveal features hitherto unknown in the anseriforms but otherwise present in galliforms. As a result, we analyzed the variable quadrate characters among all extant galloanserine families and identified synapomorphies and other morphological variation among the major galloanserine clades. In terms of quadrate morphology, Presbyornis is more plesiomorphic than any extant anseriform (including the Anhimidae) and shares ancestral galloanserine characters with the Megapodiidae, the earliest branch of extant galliforms. The quadrate's morphology is inconsistent with the currently accepted anseriform phylogeny that nests Presbyornis within the crown‐group as a close relative of the Anatidae. The presbyornithid quadrates exhibit an unusual variation in the presence of a caudomedial pneumatic foramen, which we interpret as a result of a discontinuous change in the growth path of the pneumatic diverticulum. Another episode of morphogenetic imbalance in the growth path of the pneumatic diverticulum may have accompanied the disappearance of the basiorbital pneumatic foramen (along with the pneumatization of the pterygoid) at the origin of the crown‐group anseriforms. This episode is marked by the striking individual variation in the presence and location of pneumatic foramina in the mandibular part of the quadrate in the Anhimidae. J. Morphol., 2010. © 2009 Wiley‐Liss, Inc.
Structure and freedom in creativity: The interplay between externally imposed structure and personal cognitive style
Authors: Sagiv Lilach , Arieli Sharon , Goldenberg Jacob , Goldschmidt Ayalla
Published: October 2009

This research investigates how creativity is influenced by externally imposed structure (how structured the task is), internal, cognitively produced, structure (how structured the individuals' cognitive style is), and the interaction between these two factors. Reviewing past literature, we find a contradiction. Studies that focused on the situational perspective found that externally imposed structure increases creativity. In contrast, studies that focused on the individual found that systematic (structured) cognitive style decreases creativity. In two empirical studies we investigated this seeming contradiction. We focused on two aspects of externally imposed structure: The construction of the task (Study 1) and the instructions provided (Study 2). The findings of both studies revealed that creativity was higher under structured conditions. We also show that intuitive individuals are more creative than systematic individuals, but mainly under free conditions, where structure is not externally imposed. Copyright © 2009 John Wiley & Sons, Ltd.
Comparative study of fatty acid composition, vitamin E and carotenoid contents of palm oils from four varieties of oil palm from Côte d'Ivoire
Authors: Monde Absalome A , Michel Françoise , Carbonneau Marie‐Annette , Tiahou Georges , Vernet Marie‐Hélène , Eymard‐Duvernay Sabrina , Badiou Stephanie , Adon Benjamin , Konan Eugène , Sess Daniel , Cristol Jean Paul
Published: October 2009

BACKGROUND: Fatty acid, tocopherol, tocotrienol and carotene contents were assessed in four oil palm species from the National Centre of Agronomical Research of Côte d'Ivoire, two of which were the basal Lamé (HP1) and Deli (HP2) collections and two of which resulted from crossings between HP1 and HP2 varieties of Eleais guineensis, HP3 and HP4 being identified as the first and second cycle selection, respectively.

RESULTS: Palm oil species were characterized by the richness in polyunsaturated fatty acids composition (48–60%) compared to saturated fatty acids (40–52%), especially the first variety, which was from the base collection, and the two hybrids ensuing from crossing. Total carotene content of those varieties was higher and accounted for 832–3575 µg g−1, and the β‐carotene level (580–2390 µg g−1) was predominant. Total vitamin E content was 864–1124 µg g−1, with a notable higher content of tocotrienols, especially γ‐and α‐tocotrienol, ranging from 400 to 515 µg g−1 and from 238 to 350 µg g−1, respectively.

CONCLUSION: Crossing seemed to be useful in improving the performance and analytical characteristics of the base collection materials. Copyright © 2009 Society of Chemical Industry
Nutrient composition of tomato products prepared using tomato grown under sodic condition with gypsum and farmyard manure treatment
Authors: Rani Varsha , Khetarpaul Neelam
Published: October 2009

BACKGROUND: The use of sodic water for crop irrigation decreases the availability of nutrients such as nitrogen, calcium, magnesium and zinc to plants and harms crop yield and quality. Crops irrigated with sodic water have been utilised in various product formulations. Gypsum and farmyard manure (FYM) are known to provide good soil amendment under sodic water irrigation. This research was therefore conducted to study the variation in nutrient composition of tomato products prepared from tomatoes irrigated with canal water (control) and those irrigated with sodic water treated with gypsum and FYM at two levels, i.e. 50% neutralisation of sodicity (G1F2) and complete neutralisation of sodicity (G2F2).

RESULTS: The contents of protein, fat, crude fibre, ash, carbohydrate and total soluble sugars in three types of tomato product were in the ranges 1.08–1.68, 0.20–0.31, 0.43–1.07, 0.83–1.06, 6.17–7.22 and 2.32–4.81 g kg−1 respectively. Tomato products prepared from tomatoes irrigated with G1F2‐treated water contained significantly (P < 0.05) less protein, fat, crude fibre, dietary fibre, calcium, magnesium, phosphorus, potassium, iron, zinc and sulfate but more ash, carbohydrate, total soluble sugars, oxalic acid, polyphenols, sodium, chloride and bicarbonate than those prepared from tomatoes irrigated with canal water and G2F2‐treated water.

CONCLUSION: The results showed that tomato crops irrigated with sodic water treated with gypsum and FYM to varying extent were effective in maintaining and improving the nutrient composition of various tomato products. Copyright © 2009 Society of Chemical Industry
Solitary fibrous tumor of the thyroid gland
Authors: Farrag Tarik Y. , Micchelli Shien , Tufano Ralph P.
Published: October 2009

We report a case of solitary fibrous tumor of the thyroid gland in a 51‐year‐old man with pre‐existing right recurrent laryngeal nerve paralysis from a congenital tracheoesophageal fistula repair as an infant. The left thyroid lobe was enlarged and soft. Fine needle aspiration biopsy via ultrasound guidance demonstrated a hypercellular aspirate composed of spindle cells with bland nuclear morphology. Given this histomorphology and immunohistochemical profile, the diagnosis of solitary fibrous tumor was considered and confirmed following left thyroid lobectomy. Laryngoscope, 2009
Effects of smoking on quality of life following sinus surgery: 4‐year follow‐up
Authors: Das Subinoy , Khichi Sunny S. , Perakis Helen , Woodard Troy , Kountakis Stilianos E.
Published: October 2009

Objectives/Hypothesis:

The purpose of this study is to report on long‐term outcomes in a prospective study comparing the quality‐of‐life outcomes in smokers and nonsmokers undergoing functional endoscopic sinus surgery.

Study Design:

Prospective clinical trial.

Methods:

A total of 235 patients were prospectively enrolled at a single tertiary academic center. Preoperative Sino‐Nasal Outcomes Test (SNOT)‐20 scores and comprehensive demographic and smoking data were obtained. Preoperative SNOT‐20 scores were compared to postoperative SNOT‐20 scores.

Results:

Long‐term follow‐up results were available in 111/185 nonsmokers (60%) and 26/50 smokers (52%). Nonsmokers had a mean preoperative SNOT‐20 score of 26.2, a short‐term follow‐up score of 10.1 (mean, 3.1 months) and a long‐term follow‐up score of 11.4 (mean, 44.2 months). Smokers had a mean preoperative SNOT‐20 score of 27.8, a short‐term follow‐up score of 5.7 (mean, 3.1 months) and a long‐term follow‐up score of 8.3 (mean, 40.3 months). The mean improvement in SNOT‐20 scores for smokers was significantly greater than nonsmokers in short‐term follow‐up (P = .044), however, no significant difference in improvement was seen between smokers and nonsmokers at long‐term follow‐up.

Conclusions:

Both smokers and nonsmokers continue to maintain a highly significant improvement in SNOT‐20 scores following endoscopic sinus surgery at long‐term follow‐up. Although smoking remains a well‐documented cause of medical morbidity, smokers maintained an improvement in quality of life after long‐term follow‐up from endoscopic sinus surgery in this prospective study. Laryngoscope, 2009
Segmental hemangiomas of the upper airway
Authors: O Teresa M. , Alexander Ronda E. , Lando Tali , Grant Nazaneen N. , Perkins Jonathan A. , Blitzer Andrew , Waner Milton
Published: October 2009

Objectives/Hypothesis:

To characterize the anatomic distribution of segmental hemangiomas of the larynx and to describe indications for treatment modalities.

Study Design:

Retrospective chart review.

Methods:

We performed a retrospective chart review of patients with cutaneous hemangiomas at a tertiary care center over a 4‐year period. Only patients with upper airway hemangiomas were studied. We reviewed the anatomic distribution of hemangiomas within the upper airway and the treatment course of each patient.

Results:

Of 1,226 patients with cutaneous hemangiomas, 108 (9%) were segmental in distribution. There were 56 patients (52%) who had a V3 distribution pattern, and 16 patients (29%) with upper airway involvement. All of these patients had associated V3 or mandibular segmental hemangiomas. As with the cutaneous manifestation, the distribution of hemangioma within the upper airway was segmental. This included the following anatomic sites: oral cavity, oropharynx, hypopharynx, intrinsic structures of the larynx, and subglottis. Many of these patients had diffuse mucosal involvement, including tracheal involvement. A total of 13 out of 16 patients underwent medical intervention, and seven also required surgical intervention. Medical management included systemic (12 patients) and intralesional (two patients) steroids. One patient received chemotherapy prior to referral. Surgical treatment included tracheostomy (four patients prior to referral) and laser ablation of subglottic involvement (total of four patients).

Conclusions:

A high percentage of patients with V3 cutaneous hemangiomas (29%) will manifest with upper airway involvement, the distribution of which is segmental. Treatment should take this diffuse pattern of involvement into consideration. Laryngoscope, 2009
The mandibulotomy: Friend or foe? Safety outcomes and literature review
Authors: Dziegielewski Peter T. , Mlynarek Alex M. , Dimitry John , Harris Jeffrey R. , Seikaly Hadi
Published: October 2009

Objective/Hypothesis:

To determine the safety outcomes of a unique mandibulotomy technique and to compare results to the world literature.

Study Design:

Retrospective review of a tertiary care head and neck cancer practice.

Methods:

A total of 220 consecutive lip‐splitting mandibulotomy access cases from 1998 to 2006 were identified in the University of Alberta's prospective head and neck surgery database and reviewed with follow‐up to June 2009. Uniform surgical technique consisting of a lower lip‐splitting incision, incisor extraction, a paramedian stair‐step osteotomy, and combination fixation with direct interosseous wires and a compression miniplate was utilized for all cases. Variations from traditional methods include adapting the compression miniplate to the reapproximated, rather than precut, mandible and utilizing a mentalis‐wire tacking stitch. The main outcome was the complication rate. Complications were recorded and separated into categories consisting of 1) fixation failure: malunion, nonunion, mandibular fracture, plate failure, wire protrusion; and 2) poor wound healing: hardware exposure, orocutaneous fistulae, osteomyelitis, and osteoradionecrosis.

Results:

Twenty‐three (10.5%) mandibulotomy‐related complications occurred in 22 (10.0%) patients. Six (2.7%) cases of fixation failure and 17 (7.7%) cases of poor wound healing were identified. The most common complication was hardware exposure. Uni‐ and multivariate regression analysis failed to show that any patient, tumor, or perioperative variables were statistically significant predictors of complications. Kaplan‐Meier analysis showed complications rates of 5.1% at 6 months, 7.0% at 12 months, and 10.2% at 24 months.

Conclusions:

The lip‐splitting mandibulotomy technique employed provides a safe and effective means of accessing difficult to reach anatomy of the upper aerodigestive tract. Laryngoscope, 2009
Tissue‐engineered trachea for airway reconstruction
Authors: Weidenbecher Mark , Tucker Harvey M. , Gilpin David A. , Dennis James E.
Published: October 2009

Objectives/Hypothesis:

Scaffold‐free cartilage has been used to engineer biocompatible and mechanically stable neotracheas in vivo. The purpose of this animal study was to determine if neotracheal constructs, implanted paratracheally, could successfully be used for segmental tracheal reconstruction.

Study Design:

Animal study.

Methods:

Culture‐expanded auricular rabbit chondrocytes were used to engineer scaffold‐free cartilage sheets. Cartilage and a strap muscle flap were wrapped around a tube and implanted paratracheally. At 12 to 14 weeks postimplantation neotracheas were used to reconstruct 20 mm tracheal defects. Surgical technique was modified several times in an attempt to decrease the amount of neotracheal obstruction and fibrosis. In one of the six rabbits, neotrachea with its intact strap muscle flap was dropped into the defect followed by an end‐to‐end anastomosis; in two animals the muscle flap was partially, and in one rabbit completely removed. In two animals the muscle flap was partially removed, the tube reinserted, and the construct reimplanted for 5 weeks to allow formation of a fibrous lining over the exposed cartilage followed by tracheal reconstruction.

Results:

All implants developed into vascularized and mechanically sound neotracheas. Following reconstruction, none of the animals showed immediate signs of respiratory distress; however, one died after 24 hours due to extensive endotracheal muscle flap edema, whereas rabbits who had undergone partial or complete muscle flap removal survived up to 39 days before developing cicatricial stenosis.

Conclusions:

Tissue‐engineered neotracheas proved to have excellent biocompatibility and stability to function under physiologic conditions, but lacked adequate endotracheal lining resulting in neotracheal stenosis. Laryngoscope, 2009
Sudden bilateral sensorineural hearing loss after intravenous cocaine injection: A case report and review of the literature
Authors: Stenner Markus , Stürmer Konrad , Beutner Dirk , Klussmann Jens Peter
Published: October 2009

Little is known about the effects of intravenous abuse of cocaine, especially on the inner ear. We report on a 26‐year‐old man who presented to our outpatient department with a sudden severe hearing loss after intravenous injection of cocaine. The audiogram on admission showed symmetric air conduction levels up to 80 dB at 4 kHz. After treatment with intravenous sodium chloride, prednisolone, and pentoxifylline, the audiogram 2 days later showed a bilateral normacusis. A review of the literature on the topic is given and possible reasons for inner ear damages caused by cocaine are discussed. Laryngoscope, 2009
Membranous labyrinth volumes in normal ears and Ménière disease: A three‐dimensional reconstruction study
Authors: Morita Norimasa , Kariya Shin , Farajzadeh Deroee Armin , Cureoglu Sebahattin , Nomiya Shigenobu , Nomiya Rie , Harada Tamotsu , Paparella Michael M.
Published: October 2009

Objectives:

The purpose of this study was to determine the normal volume ranges of cochlear duct, saccule, and utricle, and to assess endolymphatic hydrops in Ménière disease.

Study Design:

Retrospective temporal bone study.

Methods:

Three‐dimensional (3‐D) images of membranous labyrinth were reconstructed from 31 normal temporal bones, six temporal bones from three patients with bilateral Ménière disease, and 16 temporal bones from eight patients with unilateral Ménière disease. Volumes of each part of membranous labyrinth were measured in each temporal bone group after 3‐D reconstruction.

Results:

The mean volumes and upper normal volume limits (over the 95% confidence interval) of the cochlear duct, saccule, and utricle were 7.67 and 9.77 mm3, 2.42 and 3.68 mm3, and 10.65 and 16.45 mm3, respectively. All three patients with bilateral Ménière disease showed endolymphatic hydrops (excess of volume over normal limits) in both ears. Of eight patients with unilateral Ménière disease, five had no symptom in the contralateral ear, whereas three patients had histories of progression from unilateral to bilateral Ménière disease 13–21 years after the initial onset. All of the diseased and three of eight contralateral ears showed endolymphatic hydrops. In contrast, no hydrops was observed in any part of the membranous labyrinth in asymptomatic ears.

Conclusions:

Our findings suggest that cochleosaccular hydrops is a sensitive finding in Ménière disease. In addition, the volume data obtained from this study could be useful as a standard value for the assessment of hydrops in diagnostic imaging of the inner ear in Ménière disease. Laryngoscope, 2009
Exponential decay for a quasilinear viscoelastic equation
Authors: Messaoudi Salim A. , Tatar Nasser‐eddine
Published: October 2009

We consider the following nonlinear viscoelastic equation
equation image
together with Dirichlet‐boundary conditions, in a bounded domain Ω and ρ > 0. We prove an exponential decay result for a class of relaxation functions. Our result is established without imposing the usual relation between g and its derivative (© 2009 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
The Paley–Wiener theorem for certain nilpotent Lie groupsJean
Authors: Ludwig Jean , Molitor–Braun Carine
Published: October 2009

We generalize the classical Paley–Wiener theorem to special types of connected, simply connected, nilpotent Lie groups: First we consider nilpotent Lie groups whose Lie algebra admits an ideal which is a polarization for a dense subset of generic linear forms on the Lie algebra. Then we consider nilpotent Lie groups such that the co‐adjoint orbits of all the elements of a dense subset of the dual of the Lie algebra 𝔤* are flat (© 2009 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
When every multilinear mapping is multiple summing
Authors: Botelho Geraldo , Pellegrino Daniel
Published: October 2009

In this paper we give a systematized treatment to some coincidence situations for multiple summing multilinear mappings which extend, generalize and simplify the methods and results obtained thus far. The application of our general results to the pertinent particular cases gives several new coincidences as well as easier proofs of some known results (© 2009 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Toward a More Practical Approach to Evaluating Programs: The Multi-Objective Realization Approach
Authors: Barclay Corlane , Osei-Bryson Kweku-Muata
Published: October 2009

Emerging trends indicate that programs are being used to deliver benefits that may not be fully harnessed from single sets of uncoordinated projects. To support this movement, it is essential to have suitable measurement frameworks to assess the contribution of these activities and supply decision makers with valuable data on whether their objectives are being realized. This paper introduces the Multi-Objective Realization Method (MORE) to help measure the strategic contributions of programs. The main principles of MORE underline the importance of a formal strategy to elicit and develop program objectives and to frame those objectives within defined measurement dimensions.
Measurement of Porosity in a Composite High Explosive as a Function of Pressing Conditions by Ultra‐Small‐Angle Neutron Scattering with Contrast Variation
Authors: Mang Joseph T. , Hjelm Rex P. , Francois Elizabeth G.
Published: October 2009

We have used ultra‐small‐angle neutron scattering (USANS) with contrast variation to measure the porosity over length scales 0.1–20 μm in a composite high explosive, PBX 9501, formulated with a deuterated binder. Here, we explore the effect of varying the pressing intensity on the PBX 9501 microstructure. Samples of PBX 9501 were die‐pressed with applied pressures ranging between 69 and 200 MPa at 90 °C. Five samples were prepared at each pressure that differed in the fraction of binder that was deuterated, resulting in a change in the neutron scattering length density contrast (Δρ) of the binder relative to that of the high explosive crystallites and voids. By using this approach to discriminate scattering from voids from that due to the binder, we determined microstructure and composition that otherwise would not have been apparent. The sample composition was determined by calculating the Porod Invariant as a function of Δρand comparing it with compositional estimates obtained from the bulk sample density. Structural modeling of the USANS data, assuming both spherical and cylindrical morphologies, allowed the mean size and size distribution of voids and binder‐filled regions to be determined.
Positron hydrogen molecule scattering under Ro‐vibrational LFCC scheme using PCOP potential below the electronic excitation threshold
Authors: Mukherjee Tapas , Sarkar Nirmal K.
Published: October 2009

Recently we have presented a Laboratory Frame Ro‐Vibrational Close Coupling (LFCC) calculation for positron hydrogen molecule scattering process using Positron Correlation Polarization (PCOP) Potential and discussed the results below positronium formation threshold (Mukherjee and Sarkar, J. Phys. B 41 125201 (2008) [1]). In the present article we have reported total (integrated) cross sections as well as vibrational excitation cross sections in higher positron energy region below the first electronic excitation threshold of hydrogen molecule for same system with same coupling scheme. The results are compared with the existing elaborate theories and the measured values. In the reported energy region the present total cross sections agree well with one of the measured values but differ with other. However, the present theoretical values for 0 → 1 and 0 → 2 vibrational excitation cross sections vary appreciably with the other results. (© 2009 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Positronium lifetime in porous VP–DVB copolymer
Authors: Zaleski Radosław , Goworek Jacek , Maciejewska Małgorzata
Published: October 2009

Porous 1‐vinyl‐2‐pyrrolidone‐divinylbenzene copolymer was studied using Positron Annihilation Lifetime Spectroscopy. A set of spectra measured at various temperatures was analysed using two methods: model parameters fitting and quantified maximum entropy. Similarity of the results obtained by entirely different methods ensure that distortion of the results arisen from inappropriate data processing was minimized. Temperature dependence of the experimental ortho‐positronium lifetimes was compared to predictions of the Extended Tao‐Eldrup model. Very good agreement in whole temperature range was found for empirical parameter Δ = 0.15 nm. Basing on PALS data and the Extended Tao‐Eldrup model the distribution of free volume sizes was derived. (© 2009 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Defects dynamics in annealed Si3N4 by positron annihilation spectroscopy
Authors: Chattopadhyay Soubhik , Dutta Sreetama , Jana Debnarayan , Chattopadhyay Sanjay , Das Debabrata , Chakrabarti Mahuya , Sanyal Dirtha , Sarkar Anindya
Published: October 2009

We report the defect generation/recovery with thermal annealing (in air) in silicon nitride (Si3N4) powders investigated from X‐ray diffraction (XRD), fourier transform infra‐red (FTIR) absorption spectroscopy and positron annihilation spectroscopy (PAS). It is found that the crystallinity of the sample is improved for annealing up to 100 °C. From 150 °C annealing, a signature of formation of amorphous background (in XRD spectrum), probably of silica, has been observed. The decrease of intensity of the IR absorption peak at ∼1090 cm–1 corresponding to Si‐O bond‐stretching vibration has been observed for the sample annealed at 100 °C. The typical variation of average positron lifetime (τav) with annealing temperature also confirms the XRD and IR findings. The ratio curve analysis of the CDBAR (coincidence Doppler‐broadening of annihilation radiation) measurement successfully probes the change in oxygen incorporation in the sample with annealing temperature. (© 2009 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Dependence of ortho‐positronium pick‐off rate on sample temperature
Authors: Mariazzi S. , Salemi A. , Brusa R. S.
Published: October 2009

At room temperature the ortho‐positronium (oPs) lifetime in porosities is well described by the rectangular Tao‐Eldrup model (RTE) [1]. Recent experiments [2‐5] at low temperature have shown unexpected deviations from the RTE predictions. In Ref. [2] a pick‐off increase is observed below 200 K in pores with size less than 2 nm, at the contrary a decrease of pick‐off is found in pores with size around 3nm. An increase of the oPs lifetime (decrease of pick‐off) at low temperature was also observed by the authors of Ref. [3‐5] in porosities with sizes from 2.3 to 4 nm. In pores with size larger than 5 nm an increase of pick‐off was again pointed out [3]. The authors of the present communication, have indicated [6] that these experimental deviations from RTE model could be due to oPs confining in small pores and to a longer oPs thermalization time in largest pores. Both the effects give a longer permanence of oPs in excited states where the pick‐off rate is higher. In this work we discuss and further develop the hypothesis reported in Ref. [6] taking also into account the effect of the temperature on the interaction of oPs with the walls of the pores. (© 2009 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Influence of 3γ‐annihilation events on o‐Ps lifetime and intensities in mesoporous materials
Authors: Sudarshan K. , Sharma S. K. , Goswami A. , Pillai K. T. , Pujari P. K.
Published: October 2009

Influence of the differences in the detection efficiencies of 2γ and 3γ events on the positron annihilation parameters have been evaluated in XAD resin samples, where a significant fraction of o‐Ps decays via 3γ‐annihilation. The contribution of 3γ‐annihilation events in the data has been changed by widening the energy window of the stop detector. The intensity of the longest lived component in these samples is found to increase with the increase in the detection window of 3γ events. Small but significant increase in life‐time with increase in the detection window of 3γ‐annihilation events is also observed. This is attributed to the inherent pore size distribution in the samples. A correlation between the increase in the lifetime and pore size distribution is established. (© 2009 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Sintering of yttria‐stabilized zirconia nanopowders studied by positron annihilation spectroscopy
Authors: Čížek J. , Melikhova O. , Kuriplach J. , Procházka I. , Konstantinova T. E. , Danilenko I. A.
Published: October 2009

A positron annihilation study of the tetragonal yttria‐stabilized zirconia (YSZ) nanopowder compacted under a high pressure and subjected to a sintering at temperatures ranging from 1000 to 1350 °C were investigated. The conventional positron lifetime and coincidence Doppler broadening measurements were performed. In the compacted nanopowder, positrons were found to annihilate mainly as trapped at vacancy‐like defects (most likely the Zr vacancies) situated in the negative space‐charge layers along grain boundaries (GB's) or at larger defects associated with GB intersections (triple points). Moreover, pores of a few‐nanometer size were detected via positronium pick‐off annihilation in the YSZ nanopowders. These pores, however, disappeared after sintering at 1000 °C and a significant grain growth takes place above this temperature. (© 2009 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
On the cure process in an epoxy‐anhydride system
Authors: Tognana Sebastián , Salgueiro Walter , Somoza Alberto
Published: October 2009

A PALS study about the influence of the cure process on the free volume in an epoxy‐anhydride system is reported. To this aim, this system was modified using different times of cure and proportion of the hardener. The o‐Ps lifetimes and their associated intensities data are together discussed with complementary information on the glass transition temperature obtained by Differential Scanning Calorimetry. (© 2009 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Multi‐event analysis of the westerly Greenland tip jet based upon 45 winters in ERA‐40
Authors: Våge Kjetil , Spengler Thomas , Davies Huw C. , Pickart Robert S.
Published: October 2009

The westerly Greenland tip jet is an intense, narrow and intermittent wind phenomenon located southeast of Cape Farewell that occurs frequently during the winter season. Using the ERA‐40 reanalysis dataset, a catalogue of 586 objectively detected westerly tip jet events is compiled for the winters 1957‐2002, and an analysis is undertaken of the character of the jet and its accompanying atmospheric features. It is shown that the tip jet frequency exhibits a significant positive correlation with both the NAO index and the latitude of the Icelandic Low. The peak wind speed and accompanying heat fluxes of the jet have values up to 30 m s−1and 600 W m−2, respectively, and are sustained for less than one day. The air parcels constituting the tip jet are shown, based upon a trajectory model and the ERA‐40 dataset, to have a continental origin, and to exhibit a characteristic deflection and acceleration around southern Greenland. The events are almost invariably accompanied both by a notable coherence of the lower‐level tip jet with an overlying upper‐level jet stream, and by a surface cyclone located to the lee of Greenland. It is also shown that the cyclone originates upstream of and is advected to the lee of Greenland, and thereby it both precedes in time and contributes dynamically to the formation of the tip jet. On this basis, it is suggested that the tip jet arises from the interplay of the synoptic‐scale flow evolution and the perturbing effects of Greenland's topography upon the flow. Copyright © 2009 Royal Meteorological Society
Variational bias correction of satellite radiance data in the ERA‐Interim reanalysis
Authors: Dee D. P. , Uppala S.
Published: October 2009

This article describes the performance of the variational bias correction system for satellite radiance data in ERA‐Interim, and considers implications for the representation of climate signals in reanalysis. We briefly review the formulation of the method and its ability to automatically develop bias estimates when radiance measurements from newly available satellite sensors are first introduced in the reanalysis. We then present several results obtained from the first 19 years (1989–2007) of ERA‐Interim. These include the identification of Microwave Sounding Unit (MSU) instrument calibration errors, the response of the system to the Pinatubo eruption in 1991, and the detection of a long‐term drift in biases of tropospheric AMSU‐A data. We find that our results support the notion that global reanalysis provides an appropriate framework for climate monitoring. Copyright © 2009 Royal Meteorological Society
Linear breeze scaling: from large‐scale land/sea breezes to mesoscale inland breezes
Authors: Drobinski Philippe , Dubos Thomas
Published: October 2009

Sea/land breezes and inland breezes have in common the ‘breeze’ appellation but are essentially different. The land/sea‐breeze horizontal extent exceeds 100 km, with the Coriolis effect dominating its dynamics. Conversely, inland breezes are confined between alternating patches of cold and warm surface temperature, over horizontal ranges never exceeding a few kilometres, with negligible Coriolis effect. Both land/sea‐breeze and inland‐breeze systems are embedded within the planetary boundary layer. Despite their superficial resemblance, however, their physics differs and this article attempts to determine the parameters controlling the transition between the processes driving large‐scale land/sea breezes and those driving inland breezes.

Rotunno's linear model of the sea breeze is extended in order to describe the transition from the sea‐breeze regime to the inland‐breeze regime, especially in terms of scaling laws. The scaling in the sea‐breeze regime obtained by Rotunno is recovered. In this regime, the breeze cell tends to have a horizontal extent comparable to the Rossby radius. For the inland‐breeze regime previously studied by Anthes, an important contribution of the present work is to take into account the effect of friction. This effect is non‐trivial, as it introduces an inner region with depth controlled by friction. We demonstrate this effect by performing an asymptotic analysis over a range of horizontal scales that are smaller than the Rossby radius but still much larger than the planetary boundary‐layer depth, hence near‐hydrostatic. All the dominant terms of the breeze circulation budget are within the inner layer, where friction and buoyancy dominate the Coriolis effect and the outer‐layer terms and determine the breeze‐cell shape and intensity. Copyright © 2009 Royal Meteorological Society
The impact of targeted observations made during the Greenland Flow Distortion Experiment
Authors: Irvine E. A. , Gray S. L. , Methven J. , Renfrew I. A. , Bovis K. , Swinbank R.
Published: October 2009

The impact of targeted sonde observations on the 1‐3 day forecasts for northern Europe is evaluated using the Met Office four‐dimensional variational data assimilation scheme and a 24 km gridlength limited‐area version of the Unified Model (MetUM). The targeted observations were carried out during February and March 2007 as part of the Greenland Flow Distortion Experiment, using a research aircraft based in Iceland. Sensitive area predictions using either total energy singular vectors or an ensemble transform Kalman filter were used to predict where additional observations should be made to reduce errors in the initial conditions of forecasts for northern Europe. Targeted sonde data was assimilated operationally into the MetUM. Hindcasts show that the impact of the sondes was mixed. Only two out of the five cases showed clear forecast improvement; the maximum forecast improvement seen over the verifying region was approximately 5% of the forecast error 24 hours into the forecast. These two cases are presented in more detail: in the first the improvement propagates into the verification region with a developing polar low; and in the second the improvement is associated with an upper‐level trough. The impact of cycling targeted data in the background of the forecast (including the memory of previous targeted observations) is investigated. This is shown to cause a greater forecast impact, but does not necessarily lead to a greater forecast improvement. Finally, the robustness of the results is assessed using a small ensemble of forecasts. Copyright © 2009 Royal Meteorological Society and Crown Copyright
European climatology of fog and low stratus based on geostationary satellite observations
Authors: Cermak Jan , Eastman Ryan M. , Bendix Jörg , Warren Stephen G.
Published: October 2009

The distribution of fog and low stratus (FLS) is of importance in nowcasting, aviation forecasting and climate applications. This paper presents satellite‐derived FLS maps as a basis for building a European FLS climatology with high spatial and temporal resolution. Averaged maps covering several winter seasons of Meteosat Second Generation (MSG) data are analysed and compared to a cloud climatology based on a 26‐year record of ground‐based visual cloud observations. The general patterns seen in both products are found to be in good agreement and plausible. Copyright © 2009 Royal Meteorological Society
Robotic‐assisted single‐incision right colectomy: early experience
Authors: Ostrowitz Matthew B. , Eschete Dennis , Zemon Harry , DeNoto George
Published: October 2009

Background

Application of laparoendoscopic single‐site surgery (LESS) is increasing across surgical disciplines. In addition to the possibility of decreased postoperative pain, LESS offers better cosmesis with virtually ‘scarless’ surgeries, while avoiding the increased costs and complexity of natural orifice surgery. Instrument conflict minimization often requires the crossing of articulating instruments, which we believe can be more intuitively facilitated using the daVinci‐S® robotic system. We describe our early experience with three robotic single‐incision right hemicolectomies.

Methods

Three robotic single‐incision right hemicolectomies were performed using the daVinci‐S robotic system, utilizing a single 4 cm incision through or around the umbilicus. The procedure was performed using three robotic arms, a 12 mm camera and two 8 mm robotic ports. A medial to lateral approach was used and an extracorporeal resection and anastomosis was performed after undocking the robot.

Results

There were no intraoperative or postoperative complications. Average operative time was 152 min. The first case was converted to non‐robotic single‐incision right hemicolectomy during mobilization of the ascending colon, due to uncontrollable air leakage around the ports. The second and third cases were successfully completed without air loss by purse‐stringing sutures around each individual port and the use of the SILS™ port, respectively.

Conclusions

Robotic‐assisted single‐incision right hemicolectomy can be successfully and safely performed using the daVinci‐S robotic system. Several techniques may be employed to prevent the loss of pneumoperitoneum. We believe right hemicolectomy lends itself to single‐site surgery because specimen extraction requires a 4 cm incision and may confer patient benefit, with decreased postoperative pain and improved cosmesis. By crossing the robotic instruments and reassigning control of the arms, the robot represents a means to help perform these procedures safely by allowing them to be performed in a more intuitive fashion. Copyright © 2009 John Wiley & Sons, Ltd.
Construction of statistical shape atlases for bone structures based on a two‐level framework
Authors: Wu Chenyu , Murtha Patricia E. , Jaramaz Branislav
Published: October 2009

Background

The statistical shape atlas is a 3D medical image analysis tool that encodes shape variations between populations. However, efficiency, accuracy and finding the correct correspondence are still unsolved issues during the construction of the atlas.

Methods

We developed a two‐level‐based framework that speeds up the registration process while maintaining accuracy of the atlas. We also proposed a semi‐automatic strategy to achieve segmentation and registration simultaneously, without knowing any prior information about the shape.

Results

We have separately constructed the atlas for the femur and spine. The experimental results demonstrate the efficiency and accuracy of our methods.

Conclusions

Our two‐level framework and semi‐automatic strategy are able to efficiently construct the atlas for bone structures without losing accuracy. We can handle either 3D surface data or raw DICOM images. Copyright © 2009 John Wiley & Sons, Ltd.
Virtobot—a multi‐functional robotic system for 3D surface scanning and automatic post mortem biopsy
Authors: Ebert Lars Christian , Ptacek Wolfgang , Naether Silvio , Fürst Martin , Ross Steffen , Buck Ursula , Weber Stefan , Thali Michael
Published: October 2009

Background

The Virtopsy project, a multi‐disciplinary project that involves forensic science, diagnostic imaging, computer science, automation technology, telematics and biomechanics, aims to develop new techniques to improve the outcome of forensic investigations. This paper presents a new approach in the field of minimally invasive virtual autopsy for a versatile robotic system that is able to perform three‐dimensional (3D) surface scans as well as post mortem image‐guided soft tissue biopsies.

Methods

The system consists of an industrial six‐axis robot with additional extensions (i.e. a linear axis to increase working space, a tool‐changing system and a dedicated safety system), a multi‐slice CT scanner with equipment for angiography, a digital photogrammetry and 3D optical surface‐scanning system, a 3D tracking system, and a biopsy end effector for automatic needle placement. A wax phantom was developed for biopsy accuracy tests.

Results

Surface scanning times were significantly reduced (scanning times cut in half, calibration three times faster). The biopsy module worked with an accuracy of 3.2 mm.

Discussion

Using the Virtobot, the surface‐scanning procedure could be standardized and accelerated. The biopsy module is accurate enough for use in biopsies in a forensic setting.

Conclusion

The Virtobot can be utilized for several independent tasks in the field of forensic medicine, and is sufficiently versatile to be adapted to different tasks in the future. Copyright © 2009 John Wiley & Sons, Ltd.
Historical reconstruction of a relictual population of wild grapevines (Vitis vinifera SSP sylvestris, Gmelin, Hegi) in a floodplain forest of the upper Seine valley, France
Authors: Arnold Claire , Schnitzler Annik , Parisot Christophe , Maurin Alexandre
Published: October 2009

Wild grapevine (Vitis vinifera ssp sylvestris) is considered to be nearly extinct in its western range as a result of the expansion of American diseases combined with drastic hydraulic works in the region. In such a context, the discovery of a population of 120 individuals, offered an excellent opportunity to evaluate the status of the plant at the current edge of its western range. We focussed on the distribution patterns and the reconstruction of the history of the population through a combination of ecological and genetic data.

Fifty‐one individual plants present in a forest plot of 9.72 ha were studied. For each individual, geographical, morphological and growth strategy data were collected. Individuals were genotyped at 14 SSR loci.

Most grapevines were clumped and their density varied between forest plots with different management over the past few centuries. Overall, the number of stems possessed by each plant ranged from one to nine. Heights varied from 14 to 24 m, with diameter ranging from 0.9 to 4.6 cm (mean = 2.4 cm).

The analysis of the genetic data showed that (i) no cultivar or rootstocks were present in the population; (ii) out of 57 individuals considered in this study, six were clones; and (iii) all 14 loci were polymorphic. Six groups were shown to be significantly related.

In spite of a relatively high‐genetic diversity, the population is currently at a critical state at the local scale because of the low chances of seedling survival for more than 1 year. The clones were also directly destroyed by human management.

The ideal way to improve the status of the wild grapevine in the Bassée Forest would be to re‐create zones of erosion as well as to create a strict conservation area or reserve encompassing the entire region. Copyright © 2009 John Wiley & Sons, Ltd.
Interference‐resistant cooperative wireless networks based on complementary codes
Authors: Liu Kuang‐Hao , Shin Hsiang‐Yi , Chen Hsiao‐Hwa
Published: October 2009

Spatial diversity in wireless networks can be attained by exploiting the broadcast nature of wireless transmission without the need of multiple antennas in individual device, leading to the implementation of cooperative communication. While most prior works focused on the single source—destination scenario, it should be more realistic to consider how to induce cooperation among multiple source‐destination pairs assisted by multiple relays. In such a case, multiple access interference (MAI) may present due to asynchronous transmissions of the users and relays. In this paper, a cooperative network architecture based on orthogonal complementary (OC) codes inherently immune to MAI is proposed. To efficiently utilize the scarce radio spectrum and codes, a centralized medium access control (MAC) protocol is proposed to coordinate the code assignment and channel access among users and relays. We theoretically analyze the bit error rate (BER) performance of the proposed OC coded cooperative network over multipath Rayleigh fading channel. The performance gain resulted from different numbers of relays is investigated, and compared with a time division multiple access (TDMA) based cooperative scheme. We show that the proposed OC coded cooperative network performs well in the presence of timing offset, and thus is well suited for asynchronous uplink transmission with cooperative relaying. Copyright © 2009 John Wiley & Sons, Ltd.
Modeling a shallow water acoustic communication channel using environmental data for seafloor sensor networks
Authors: King Peter , Venkatesan Ramachandran , Li Cheng
Published: October 2009

Development of communication channels for underwater sensor networks holds many unique challenges. Communication near the bottom of the ocean is no exception as the effects of reflection and refraction greatly affect how acoustic waves travel between a source and an intended receiver. Deployment and testing in the ocean are difficult and expensive; thus there is a strong reliance on models to aid in design and development of a potential network. Since each ocean region can present very unique challenges, it is of great value to model an environment based on real environmental parameters whenever available. A well prepared channel model will provide the ability to show channel capacity as it relates to node positions, as well as showing the performance of modulation techniques to an environment with propagation characteristics and path arrivals. This channel model will also be implementable into a simulation package to allow for high quality simulation of higher level protocols. The proposed method has proved to be a useful tool in modeling a particular environment and provides insight into underwater sensor node placement and modulation. Copyright © 2009 John Wiley & Sons, Ltd.
Transplacental transport of nanomaterials
Authors: Saunders Margaret
Published: October 2009

The unique properties of nanoparticles (NP) are key to the excitement over their potential application to benefit many aspects of our lives, but are also the cause of concern over inadequate toxicological assessment of their possible impact on human health. Nanotechnology is a rapidly expanding area of industrial activity in which NP are being developed for a wide range of purposes. With some of these products already in use, and many more soon to follow, it is critically important that the potential risks from this new technology are properly assessed. There is a pressing need to understand how engineered NP can interact with the human body following exposure as consumers, in the workplace or from the environment and fundamental to this is the assessment of NP interactions at biological barriers, which control access to the whole organism and specific organs. The placenta is a barrier of particular interest because it determines exposure of the foetus that represents a vulnerable and sensitive subpopulation requiring additional consideration. Little is currently known about whether NP can cross the human placental barrier or interfere with placental function but suitable transport models have been developed which can be used to clarify the mechanisms of cellular interaction and transport across the placenta. Copyright © 2009 John Wiley & Sons, Inc.

This article is categorized under:

Toxicology and Regulatory Issues in Nanomedicine > Toxicology of Nanomaterials