bluuebunny/crossref_metadata_2025 huggingface dataset:
Acceptability of scab‐resistant versus conventional apple cultivars by Polish adult and young consumers
Authors: Tomala Kazimierz , Baryłko‐Pikielna Nina , Jankowski Paweł , Jeziorek Kamil , Wasiak‐Zys Grażyna
Published: March 2009

BACKGROUND: One of the problems in marketing fruit is to increase the share of fruits produced in sustainable agriculture to meet the expectation of ecology‐oriented consumers. Acceptability of such fruits by the consumers is of paramount importance. The objective of this study was to explore the acceptability of three scab‐resistant apple cultivars as compared with three popular conventional cultivars by Polish consumers of various age groups (adults, youngsters and children). Acceptability was tested on apples harvested in two consecutive years (2004 and 2005) after 2 months cold storage. Apple samples were chosen among 22 conventional and scab‐resistant cultivars for their distinctive differences in sensory profiles. Consumers evaluated separately the degree of external (appearance) and internal (flavour and texture) liking of an apple using a 9‐point hedonic scale (children used a 5‐point scale) and completed a questionnaire detailing socio‐demographic and apple‐concerning behavioural questions.

RESULTS: The results based on internal liking data have shown that in all age groups, consumers were similarly segmented into three clusters: cluster 1, which liked all cultivars a great deal and equally; cluster 2, which preferred firm, juicy and rather acidic fruits; and cluster 3, which liked sweeter apples with intensive ripe apple flavour and moderate firmness.

CONCLUSION: It is concluded that scab‐resistant cultivars with the above sensory characteristics might be accepted by quite a large segment of consumers, in each of the age groups tested. Copyright © 2009 Society of Chemical Industry
Analysis of pomegranate seed oil for the presence of jacaric acid
Authors: Sassano Gary , Sanderson Paul , Franx Johan , Groot Pascal , van Straalen Jeroen , Bassaganya‐Riera Josep
Published: March 2009

BACKGROUND: Pomegranate seed oil is predominantly composed of triglycerides containing unsaturated fatty acids, including high levels of conjugated linolenic acids (CLnAs). The major CLnA component, punicic acid, is known to possess biological activity. Consequently, it is desirable to obtain a detailed characterisation of pomegranate seed oil fatty acid profiles, including molecules potentially co‐eluting with punicic acid, such as jacaric acid.

RESULTS: Conjugated fatty acid profiles of a commercial sample of cold pressed pomegranate seed oil were characterised in detail by both gas chromatography of methyl esters and by 13C NMR spectroscopy. The methylation procedures were found to be critical for determination of accurate fatty acid profiles. GC analysis was unable to resolve jacaric acid from punicic acid, the major fatty acid present in pomegranate seed oil. To establish the presence or absence of jacaric acid, 13C NMR was employed.

CONCLUSION: This is the first study to investigate pomegranate seed oil for the presence of jacaric acid. Punicic acid, eleostearic acid, and catalpic acid were confirmed by 13C NMR, but jacaric acid was not found. Thus, we have shown that punicic acid levels may be accurately measured by gas chromatography alone in pomegranate seed oil. Copyright © 2009 Society of Chemical Industry
Expression analysis of endo‐1,4‐β‐glucanase genes during aril breakdown of harvested longan fruit
Authors: Xiao Ruo , Chen Jian‐ye , Chen Jian‐wen , Ou Min , Jiang Yue‐ming , Lin He‐tong , Lu Wang‐jin
Published: March 2009

BACKGROUND: The aim of the present study was to investigate the expression profiles of three endo‐1,4‐β‐glucanase (EGase, EC 3.2.1.4) genes during aril breakdown of longan fruit stored at room temperature (25 °C), low temperature (10 °C) or on transferring fruit stored at 10 °C for 20 days to 25 °C.

RESULTS: Three longan full‐length cDNAs, designated Dl‐EGase1, Dl‐EGase2 and Dl‐EGase3, were isolated and characterized. EGase activity in aril tissues of longan fruit increased with the appearance of aril breakdown symptoms, while RNA gel blot analysis revealed that the accumulations of three Dl‐EGase genes exhibited differential characteristics with the occurrence of aril breakdown. Dl‐EGase2 may be involved in the aril breakdown in longan fruit at the later stage of storage at room temperature. Conversely, expression of Dl‐EGase3 could be mainly involved in aril breakdown of fruit stored at 10 °C. In addition, Dl‐EGase3 and Dl‐Egase2 were related to the aril breakdown of fruit transferred from low temperature to room temperature.

CONCLUSION: The results obtained in this study indicate that Dl‐EGase genes are involved in the aril breakdown of longan fruit and that considerable variation exists between expression patterns of individual members of the EGase gene family. Copyright © 2009 Society of Chemical Industry
Pelvic floor stimulation: What are the good vibrations?
Authors: Lauper Monika , Kuhn Annette , Gerber Regina , Luginbühl Helena , Radlinger Lorenz
Published: March 2009

Objective

The aim of this study was to determine if two different whole body vibration, sinusoidal vibration (SV) and stochastic resonance vibration (SRV), using various intensities lead to a reactive activation of pelvic floor muscles.

Study Design

We compared the pelvic floor muscle response of a healthy control group with that of a post partum group with weakened pelvic floor contraction. Activation effects of stochastic resonance vibration and sinusoidal vibration with six increasing vibration intensities were investigated using pelvic floor EMG and compared to activity during rest and maximum voluntary contraction.

Results

Both whole body vibration systems were able to activate pelvic floor muscles significantly depending on vibration intensity. Generally, the SRV achieved a significantly higher activation than maximum voluntary contraction, especially in women post partum and using a frequency of 6–12 Hz.

Conclusion

SRV, compared to SV, leads to higher pelvic floor muscle activation in subjects with weakened pelvic floor muscles and achieves higher pelvic floor activation than maximum voluntary contraction alone. Neurourol. Urodynam. 28:405–410, 2009. © 2009 Wiley‐Liss, Inc.
Rigid body dynamics in terms of quaternions: Hamiltonian formulation and conserving numerical integration
Authors: Betsch Peter , Siebert Ralf
Published: March 2009

In the present paper unit quaternions are used to describe the rotational motion of a rigid body. The unit‐length constraint is enforced explicitly by means of an algebraic constraint. Correspondingly, the equations of motion assume the form of differential‐algebraic equations (DAEs). A new route to the derivation of the mass matrix associated with the quaternion formulation is presented. In contrast to previous works, the newly proposed approach yields a non‐singular mass matrix. Consequently, the passage to the Hamiltonian framework is made possible without the need to introduce undetermined inertia terms. The Hamiltonian form of the DAEs along with the notion of a discrete derivative make possible the design of a new quaternion‐based energy–momentum scheme. Two numerical examples demonstrate the performance of the newly developed method. In this connection, comparison is made with a quaternion‐based variational integrator, a director‐based energy–momentum scheme, and a momentum conserving scheme relying on the discretization of the classical Euler's equations. Copyright © 2009 John Wiley & Sons, Ltd.
Individual and family adaptation in Taiwanese families of individuals with severe and persistent mental illness (SPMI)
Authors: Hsiao Chiu‐Yueh , Riper Marcia Van
Published: March 2009

The purpose of this study was to examine individual and family adaptation in Taiwanese families of persons with severe and persistent mental illness. Mediating effects of social support and meaning of family caregiving on the relationship between pile‐up of demands and family adaptation were also assessed. Data were collected from 84 families using mailed questionnaires and analyzed using principal component analysis and mixed linear modeling. Adaptation was associated with lower pile‐up of demands, greater social support, and more positive interpretation of family caregiving. Partially mediating effects of social support and meaning of family caregiving were supported. The results imply a need for developing culturally sensitive interventions to decrease family demands and amplify individual, family, and community strengths and resources. © 2009 Wiley Periodicals, Inc. Res Nurs Health 32:307–320, 2009
A randomized trial investigating an exercise program to prevent reduction of bone mineral density and impairment of motor performance during treatment for childhood acute lymphoblastic leukemia
Authors: Hartman A. , te Winkel M.L. , van Beek R.D. , de Muinck Keizer‐Schrama S.M.P.F. , Kemper H.C.G. , Hop W.C.J. , van den Heuvel‐Eibrink M.M. , Pieters R.
Published: March 2009

Background

Reduced bone mineral density (BMD), altered body composition, impaired motor performance and passive ankle dorsiflexion are side effects of acute lymphoblastic leukemia (ALL) treatment. We performed a randomized study investigating whether an exercise program could prevent these side effects.

Procedure

At diagnosis we randomized 51 ALL patients (median age: 5.4 years) into a group receiving a 2‐year exercise program or a control group receiving standard care. BMD of total body (BMDTB), lumbar spine (BMDLS) and body composition were measured using dual energy X‐ray absorptiometry, motor performance with Bayley Scales of Infant Development or Movement‐ABC, and passive ankle dorsiflexion with a goniometer. The investigator was blinded to the randomization.

Results

Body fat increased equally during treatment in both groups. One year after cessation of therapy more rapid decline of excessive body fat was observed in the intervention group than in the controls (P = 0.01). Lean body mass, BMDTB and BMDLS of both groups decreased equally during treatment and increased equally thereafter. Both groups showed a similar decrease in passive ankle dorsiflexion and motor performance during treatment. Adherence to the intervention program varied considerably. Adherence to intervention: 11% of children exercised daily, 37% > once a week, 16% once weekly, 36% < once a week.

Conclusions

The exercise program was not more beneficial than standard care in preventing reduction in BMD, motor performance and passive ankle dorsiflexion than standard care, most likely due to unsatisfactory compliance. Increased BMI and body fat in the intervention group normalized faster after cessation of chemotherapy. Pediatr Blood Cancer 2009;53:64–71. © 2009 Wiley‐Liss, Inc.
Pediatric duodenal cancer and biallelic mismatch repair gene mutations
Authors: Roy Sumita , Raskin Leon , Raymond Victoria M. , Thibodeau Stephen N. , Mody Rajen J. , Gruber Stephen B.
Published: March 2009

Gastrointestinal malignancies are extremely rare in the pediatric population, and duodenal cancers represent an even more unusual entity. Intestinal cancers in young adults and children have been observed to be associated with functional deficiencies of the mismatch repair (MMR) system causing a cancer‐predisposition syndrome. We report the case of a 16‐year‐old female with duodenal adenocarcinoma and past history of medulloblastoma found to have a novel germline bialleleic truncating mutation (c.[949C>T]+[949C>T]) of the PMS2 gene. Pediatr Blood Cancer 2009;53:116–120. © 2009 Wiley‐Liss, Inc.
Life‐threatening retroperitoneal bleeding due to warfarin–drug interactions
Authors: Chan Thomas Y. K.
Published: March 2009

Warfarin–drug interactioions, which can result in life‐threatening bleeding, are preventable. A 53‐year‐old man was admitted to hospital with exacerbation of chronic obstructive airways disease, cor pulmonale, pneumonia, deep vein thrombosis and acute pulmonary embolism. His pulmonary thromboemobolism was initially treated by low‐molecular‐weight‐heparin and heparin. After a loading dose of 5 mg for 2 days, warfarin was given in a daily dose of 2 mg. On the fifth day of warfarin therapy, the last dose of Enoxaparin was given in the morning. He had a fall in the bathroom with blunt injury to the right flank. He complained of right thigh numbness and increasing pain and swelling over his right flank and abdomen. A tender mass was noted over the right flank. His Hb level dropped to 9.7 g/dl. His INR increased from 2.46 to 3.49–3.71 one day later. On further questioning, he admitted self applications of 20 g of Analgesic balm (50% methyl salicylate) over his right calf for 3 days. CT scan showed a large right retroperitoneal haematoma and right iliacus intramuscular haematoma. Warfarin was withheld. He was given fresh frozen plasma, packed cells and vitamin K1. Inferior vena cava filter was inserted. The haematomas were resolving. He was subsequently discharged to convalescence hospital for continuation of anticoagulant therapy and close monitoring. Significant usage of topical methyl salicylate ointment can potentiate the anticoagulant effect of warfarin. The over‐anticoagulation and the presence of platelet dysfunction increase the risk of severe bleeding, which can be provoked by trauma. Copyright © 2009 John Wiley & Sons, Ltd.
Vibrational dynamics of poly(β‐hydroxybutyrate)‐α form
Authors: Chaturvedi Deepika , Mishra Soni , Tandon Poonam , Gupta Vishwambhar Dayal , Siesler H.W.
Published: March 2009

Poly(β‐hydroxybutyrate) (PHB) (CH(CH3)CH2COO)n is a biodegradable polymer and it has various important applications in the biomedical field. In the present communication a comprehensive study of the normal modes and their dispersion in the α form of PHB using Urey Bradley force field is being reported. Optically active frequencies corresponding to zone center and zone boundary are assigned and characteristic features of dispersion curves are discussed. Heat capacity has been calculated via density‐of‐states using Debye relation in the temperature range 10–450 K. POLYM. ENG. SCI., 2009. © 2009 Society of Plastics Engineers
Urethane dimethacrylate oligomers for dental composite matrix: Synthesis and properties
Authors: Buruiana Tinca , Buruiana Emil C. , Melinte Violeta , Colceriu Aurora , Moldovan Marioara
Published: March 2009

Two urethane poly(ethylene oxide) dimethacrylates based on polyether diol of variable length (Mn: 300 and 1000 g/mol), isophorone diisocyanate and 2‐hydroxyethyl methacrylate, were synthesized and characterized to be used as comonomers for dental composites. The polymerization process initiated with benzoyl peroxide/amine or camphorquinone/tertiary amine couple was followed by a combination of FTIR spectroscopy and fluorescence technique using a pyrene probe for the in situ monitoring of microscopic changes in the polymeric systems. Difference in the polymerization kinetics of the oligomers and low‐molecular‐weight monomer is presented in connection with the chemical structure of the urethane dimethacrylate, taken together with another partners (bisGMA, TEGDMA, filler) with effect on the mobility and reactivity of the formed polymeric network. The results suggest a higher reactivity of the oligomeric forms and are in agreement with the fluorescence measurements induced of the pyrene molecule, whosemonomer fluorescence emission significantly increased with irradiation time as the network formation occurred. Measurements of the contact angle showed the maintenance of the hydrophilic nature of these resins, while the values of polymerization shrinkage and diametral tensile and compressive strengths of the three specimens indicated that the incorporation of dimethacrylate urethane oligomers in the organic matrix (18 wt%) led to materials with good properties. POLYM. ENG. SCI., 2009. © 2009 Society of Plastics Engineers
Effect of γ‐ray irradiation on morphology and electrical properties of poly(vinyl chloride)/graphite composites
Authors: Srivastava Nalin K. , Rattan Sunita , Mehra Ram M.
Published: March 2009

This article reports the effect of crosslinking by γ‐ray irradiation on the morphology, electrical properties, and hardness of poly(vinyl chloride)/graphite composite. A comparison of the scanning electron micrographs of the composites, before and after irradiation, showed that the filler particles were broken into pieces and distributed homogenously as a result of irradiation. The data of electrical conductivity versus graphite content was found to be consistent with the percolation model. A significant increase in the conductivity of composite was observed on the crosslinking of the polymer in consequence of irradiation. The data are correlated with the morphological changes. The study of electrical resistivity as a function of temperature revealed that the negative temperature coefficient of resistivity effect is considerably suppressed after irradiation. These results are explained on the basis of morphological changes in the composites after γ‐ray irradiation. POLYM. ENG. SCI., 2009. © 2009 Society of Plastics Engineers
Synthesis and characterization of nano‐sized epoxy oligosiloxanes for fabrication of transparent nano hybrid materials
Authors: Yang Seungcheol , Kim Jeong Hwan , Jin Jung Ho , Bae Byeong‐Soo
Published: March 2009

Nano‐sized epoxy oligosiloxanes (EO) were prepared by condensation reaction between 3‐glycidoxypropyltrimethoxysilane (GPTS) and Diphenylsilandiol (DPSD). Through a composition change of GPTS and DPSD, EO of various structure and sizes were obtained. The molecular structure and size of EO synthesized were investigated by experimental measurements. Regardless of their composition, molecular structure of EO was linear or branch. The amount of species of high molecular weight and their molecular size increased with addition of DPSD. We confirmed that epoxy groups of EO were thermally cured using a thermal initiator and curing agent. Finally, we fabricated transparent epoxy‐based hybrimer films by thermal curing of EO resins. © 2009 Wiley Periodicals, Inc. J Polym Sci Part B: Polym Phys 47: 756–763, 2009
Structure–property relationships in polyamide 6/multi‐walled carbon nanotubes nanocomposites
Authors: Logakis Emmanuel , Pandis Christos , Peoglos Vasilios , Pissis Polycarpos , Stergiou Charalampos , Pionteck Jürgen , Pötschke Petra , Mičušík Matej , Omastová Mária
Published: March 2009

Polyamide 6 (PA6)/multi‐walled carbon nanotubes (MWCNT) nanocomposites were produced by diluting a masterbach containing 20 wt % nanotubes using melt mixing. The influence of the addition of well dispersed MWCNT (as indicated by scanning electron microscopy (SEM) and transmission electron microscopy (TEM)) on the thermal transitions, and crystallization behavior of the PA6 matrix is investigated. Differential scanning calorimetry (DSC) results show a reduction in heat capacity jump at the glass transition which is interpreted by an immobilized interfacial layer near the nanotubes. Furthermore, both DSC and X‐ray diffraction (XRD) measurements indicate that nanotubes favor the formation of the α crystalline form of PA6. These findings are correlated with the observed improvement of the storage modulus as revealed by dynamic mechanical thermal analysis (DMTA). Additionally, a new crystallization peak appears when MWCNT are added, and is attributed to the formation of a different morphology of the same type crystallite around the nanotubes walls (trans‐crystallinity). Finally, water sorption measurements show an increase of water content, normalized to the amorphous polymer fraction, in the nanocomposites. © 2009 Wiley Periodicals, Inc. J Polym Sci Part B: Polym Phys 47: 764–774, 2009
Clinic and radiological improvement of lipoid pneumonia with multiple bronchoalveolar lavages
Authors: Sias Selma M.A. , Daltro Pedro A. , Marchiori Edson , Ferreira Angela S. , Caetano Regina L. , Silva Cleonice S. , Müller Nestor L. , Moreira Jose , Quirico‐Santos Thereza
Published: March 2009

Objective

To assess the potential role of multiple bronchoalveolar lavages (BALs) in the treatment of children with lipoid pneumonia (LP).

Materials and Methods

This prospective study included 10 children (7 female, 3 male) with LP secondary to mineral oil aspiration. The age ranged from 3 months to 7 years and 1–60 days history of mineral oil intake, with a 6 months clinic follow‐up. High‐resolution computer tomography (CT) was performed 1–7 days prior to treatment and 2–20 days after the last therapeutic BAL, and reviewed by two experienced chest radiologists. Oxygen saturation was measured with digital oximetry. Therapeutic BAL was performed weekly until BAL fluid was nearly transparent and the cell count returned to normal range values.

Results

In all children, the initial CT scans showed multifocal bilateral consolidation involving mainly the dorsal and central regions. The areas of consolidation had foci of decreased attenuation in eight patients. Following a total of 4–10 therapeutic BALs, the CT scans returned to normal in 3 patients, improved considerably in 5, and showed only slight improvement in 2. Oxygen saturation increased from 88.8 ± 3.4% at presentation to 96.2 ± 0.8% after treatment (P < 0.0001). Multiple lavages reduced (P < 0.003) numbers of lipid‐laden macrophages and restored BAL cellularity to normal range values.

Conclusion

Multiple therapeutic BAL of children with LP results in significant improvement of CT findings, oxygen saturation, restoration of BAL fluid cellularity and clinical recover without any evidence of respiratory distress at the end of treatment and 6 months after the last BAL. Pediatr Pulmonol. 2009; 44:309–315. © 2009 Wiley‐Liss, Inc.
Endobronchial ultrasound in pediatric pulmonology
Authors: Steinfort Daniel P. , Wurzel Danielle , Irving Louis B. , Ranganathan Sarath C.
Published: March 2009

Endobronchial ultrasound (EBUS) is a recently introduced technique that has significantly advanced bronchoscopic techniques in adult medicine. Use of ultrasound allows far more accurate localization and sampling of both peripheral pulmonary, as well as mediastinal and hilar lesions. This has led to greater diagnostic success, with a reduced rate of complications. Its performance characteristics in adult populations are equivalent to surgical procedures previously considered gold standard, but it has dramatically reduced morbidity and mortality among patients requiring invasive diagnostic procedures, when compared to surgical approaches. We describe the types of EBUS in clinical use, the method of use, the clinical indications for each procedure, and the potential role for EBUS in pediatric pulmonology. Radial probe EBUS is used in the investigation of peripheral lung lesions and could be adopted in children to achieve accurate biopsy of such lesions. Linear probe EBUS allows minimally invasive biopsy of mediastinal and hilar lesions. It has potentially greater performance characteristics than current biopsy techniques, with no significant complications reported to date. It may be useful in the diagnosis of lymphoma, or neurogenic tumors, as well as many other diseases resulting in mediastinal or hilar lymphadenopathy. EBUS is a minimally invasive technique that allows tissue sampling of peripheral lung lesions, or mediastinal/hilar masses, with a high diagnostic accuracy, and a significantly lower morbidity and mortality than alternative approaches. The indications for and the use of EBUS in pediatric patients is certain to increase in the future. Pediatr Pulmonol. 2009; 44:303–308. © 2009 Wiley‐Liss, Inc.
Phrenic nerve palsy in children associated with confirmed intrathoracic tuberculosis: Diagnosis and clinical course
Authors: Goussard P. , Gie R.P. , Kling S. , Andronikou S. , Janson J.T. , Roussouw G.J.
Published: March 2009

In this descriptive retrospective cases series of eight cases phrenic nerve palsy in children caused by tuberculosis lymph gland infiltration of the phrenic nerve. The lymph gland enlargement was in all cases caused by culture confirmed Mycobacterium tuberculosis. The phrenic nerve palsy was on the left side in all eight cases with the presenting feature a raised diaphragm on chest radiography that was accompanied by consolidation of the left upper lobe (88%) The diagnosis of phrenic nerve palsy was confirmed by fluoroscopy of the chest. On computer tomography the outstanding features were left sided hilar and paratracheal lymph gland enlargement with displacement of the mediastinum to the right. Mediastinal displacement lead to anterior displacement of the descending aorta, which further compressed the left main bronchus. Two children had accompanying respiratory failure requiring assisted ventilation and in two additional cases the airway compression was so severe that glandular enucleation of the enlarged glands was indicated. Of the eight children five remained symptomatic after completion of TB treatment to which steroids were added for the initial month. Diaphragmatic plication was indicated in all five cases. On clinical follow‐up two children had repeated respiratory tract infections secondary to underlying lung damage while the other six remained asymptomatic. Pediatr Pulmonol. 2009; 44:345–350. © 2009 Wiley‐Liss, Inc.
Sleep associated gas exchange abnormalities in children and adolescents with habitual snoring
Authors: Carno Margaret‐Ann , Modrak Joseph , Short Renee , Ellis Ethan R. , Connolly Heidi V.
Published: March 2009

Study Objectives

The purpose of this study was to describe the prevalence of polysomnographically diagnosed OSAS and to describe the severity of sleep associated gas exchange abnormalities (SAGEA) in habitually snoring children. We hypothesized that there would be a high prevalence of OSAS in obese children with habitual snoring and that the most overweight children would have the most significant SAGEA.

Design

Retrospective chart review.

Measurements and Results

Nocturnal polysomnography (NPSG) data from 114 children and adolescents referred for habitual snoring were examined. 74 of the subjects were male (65%), average age of 9.78 ± 4.19 years, average AHI 13.51 ± 20.25, mean BMI z‐score 1.79 ± 1.18. BMI z‐scores correlated positively with severity of OSAS (P < 0.05) such that children with progressive degrees of obesity had more frequent respiratory events during sleep. Additionally, severity of sleeping hypercapnea as measured by percent of total sleep time with EtCO2 values above 50 mm Hg was more severe with progressive degrees of obesity. Likewise, all measures of oxyhemoglobin desaturation were more severe with progressive degrees of obesity. Positive correlations between the severity of SAGEA and degree of obesity remained even after controlling for the severity of OSAS.

Conclusions

OSAS is highly prevalent in children referred to a pediatric sleep center with complaints of habitual snoring across a wide spectrum of weight categories. SAGEA increases with progressive obesity even when controlling for the severity of OSAS suggesting that obesity is an independent risk factor for SAGEA. Furthermore, because obese children frequently have SAGEA, capnography should be obtained during NPSG when possible. Pediatr Pulmonol. 2009; 44:364–372. © 2009 Wiley‐Liss, Inc.
Position and ventilatory response to added dead space in prematurely born infants
Authors: Rao Harish , Saiki Tolulope , Landolfo Francesca , Smith Adam P.R. , Hannam Simon , Rafferty Gerrard F. , Milner Anthony D. , Greenough Anne
Published: March 2009

Objectives

Prematurely born infants are at increased risk of sudden infant death syndrome (SIDS) if slept prone.

Working Hypothesis

Prematurely born infants would have an impaired response to an added dead space and lower respiratory muscle strength in the prone compared to the supine position.

Study design

Prospective study.

Patient‐Subject Selection

Twenty‐five infants, median gestational age of 30 (range 26–32) weeks.

Methodology

The infants were studied supine and prone at a median of 36 weeks postmenstrual age. Breath by breath minute volume was measured at baseline and after a dead space was incorporated into the breathing circuit; the time constant of the response was calculated. The maximum inspiratory occlusion pressure generated (MIOP) and the pressure generated over the first 100 msec (P0.1) during airway occlusion were assessed.

Results

The median time constant was longer (26 (range 8–106) sec vs. 22 (range 6–92) sec (P = 0.045)) and the median MIOP (P = 0.001) and P0.1 (P = 0.003) were lower in the prone compared to the supine position.

Conclusion

Prematurely born infants have a dampened response to tube breathing and reduced respiratory muscle strength in the prone compared to the supine position, which may contribute to their increased vulnerability to SIDS in the prone position. Pediatr Pulmonol. 2009; 44:387–391. © 2009 Wiley‐Liss, Inc.
Macroporous silicon hydrogen diffusion layers for micro‐fuel cells
Authors: Desplobain S. , Gautier G. , Ventura L. , Bouillon P.
Published: March 2009

In this study, we have demonstrated the possibility of using macroporous silicon as a hydrogen diffusion layer in integrated micro fuel cells. Macroporous silicon was used to increase an exchange surface between hydrogen and active layers of micro fuel cells. Moreover, electrochemical etching is an interesting alternative to costly Deep Reactive Ion Etching techniques. A maximum density power of 250 mW/cm2 was demonstrated using conventional proton exchange membrane micro fuel cell. (© 2009 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Biomolecule size‐dependent sensitivity of porous silicon sensors
Authors: Rong Guoguang , Weiss Sharon M.
Published: March 2009

Nanoporous materials hold great potential for improving the performance of biosensors due to their large available surface area and their capability for size‐selective infiltration. One of the principal challenges associated with the use of nanopores is achieving efficient infiltration of molecules whose size is of the same order of magnitude as the pore radius. There is an intrinsic trade‐off between ease of infiltration and level of sensor response for the detection of biomolecules in nanopores. DNA molecules of lengths between approximately 1.5 nm and 5.5 nm have been exposed to porous silicon waveguide sensors with nanopore diameters of approximately 30 nm in order to experimentally determine the size‐dependent sensitivity. While theoretical calculations that do not take into account the infiltration challenges of biomolecules in nanopores suggest that longer DNA molecules yield a stronger sensor response, experimental results show that shorter molecules produce a larger response due to their ease of infiltration. (© 2009 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Characterization of Fe 3d states in CuFeS2 by resonant X‐ray emission spectroscopy
Authors: Sato Katsuaki , Harada Yoshihisa , Taguchi Munetaka , Shin Shik , Fujimori Atsushi
Published: March 2009

Resonant X‐ray emission spectroscopy (RXES) experiments were carried out in a single crystal of chalcopyrite CuFeS2, an antiferromagnetic semiconductor with a golden lustre, to unravel the overlapping d–d and charge‐transfer transitions extending well above the absorption edge, which cannot be observed by conventional optical absorption experiments. The observed RXES spectra have been analyzed by means of cluster‐model calculation with configuration interaction, which leads to the conclusion that CuFeS2 is a Haldane–Anderson insulator with a negative value of charge transfer energy, Δ = –3 eV. (© 2009 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Progress in sulfosalt research
Authors: Dittrich Herbert , Stadler Andreas , Topa Dan , Schimper Hermann‐Josef , Basch Angelika
Published: March 2009

An overview over the progress in sulfosalts research is given, including basic and application oriented research work. The ternary and multinary compound semiconductor family is defined. The chemical composition possibilities are given as well as an introduction to the structural systematics. The peculiarities of the complex crystal structures are outlined. The main characteristics of thermodynamic properties are given exemplarily by the SnS–Sb2S3 pseudo‐binary phase diagram. A new phase in the Sn–Sb–S system, SnSb4S7, is reported and the new crystal structure is shown. The published methods of synthesis, thin film deposition, and nanoparticle preparation are listed in tables. A detailed listing of different methods, used for sulfosalt thin film deposition is presented. Data of physical properties are collected and presented. A compilation of measured bandgaps is given. The potential of sulfosalts in possible applications and the role in actual applications are widespread. They include photovoltaic (thin film solar cells) and thermoelectric energy conversion (thermoelectric generator, Peltier elements), phase change memory (rewritable compact discs), catalysis, X‐Ray detectors, and cryoelectronics. (© 2009 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
In0.11Ga0.89N‐based p‐i‐n photodetector
Authors: Su Y. K. , Lee H. C. , Lin J. C. , Huang K. C. , Lin W. J. , Li T. C. , Chang K. J.
Published: March 2009

The InGaN photodetector with a In composition of i‐In0.11Ga0.89N active layer have been fabricated by MOCVD system. From the photoluminescence measurement, the FWHM of InGaN epitaxial layer was only 13.8 nm. The strong luminescence peak was located at wavelength of 399 nm. We also found that the FWHM of X‐ray diffraction of GaN and InGan layer were 218 and 350 arcsec, respectively. Clear photo‐responses are also observed in InGaN photodetector with 11% content at responsivity measurement. The cut‐off range of spectral responsivity was occurred at 400 nm. The highest spectral responsivity of photodetector was 0.206 A/W at wavelength of 380 nm. The rejection ratio was approached to 103. The external quantum efficiency was about 67%. The current density‐voltage (J‐V) characteristic of i‐InGaN p‐i‐n photodetector was measured. The dark and photo current density were 1.77×10‐4 A/cm2 and 4.5×10‐2 A/cm2 when biased at ‐3 V, respectively. At photovoltaic characteristics, the Voc and Jsc of the i‐InGaN photodetector are 1.63 V and 3.1×10‐2 A/cm2, respectively. The fill factor of i‐InGaN p‐i‐n photodetector was about 37%. (© 2009 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
AlInN/GaN based multi quantum well structures – growth and optical properties
Authors: Hums Christoph , Gadanecz Aniko , Dadgar Armin , Bläsing Jürgen , Lorenz Pierre , Krischok Stefan , Bertram Frank , Franke Alexander , Schaefer J. A. , Christen Jürgen , Krost Alois
Published: March 2009

High indium content ([In>]25%) AlInN/GaN multi quantum well structures grown by metal organic vapor phase epitaxy were analyzed by X‐ray diffraction, X‐ray reflection, and photoluminescence measurements. The samples, which exhibit an excellent crystalline quality and smooth interfaces, are found to show broad luminescence below the GaN‐bandgap which shifts with increasing indium content to longer wavelength. At elevated indium content an additional broadening of the luminescence band has been observed. A comparison of the AlInN bandgap and the luminescence energies shows a pronounced stokes shift. XPS measurements reveal a staggered band lineup in Al1‐xInxN /GaN heterostructures with x > 0.25 is found. These findings indicate an indirect transition from the AlInN conduction to the GaN valence band as origin of the luminescence behavior. (© 2009 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Non‐polar AlN and GaN/AlN on r‐plane sapphire
Authors: Ranalli Fabio , Parbrook Peter J. , Bai Jie , Lee Kean B. , Wang Tao , Cullis Antony G.
Published: March 2009

We report on the morphological, structural and optical properties of a ‐plane GaN grown on r ‐plane sapphire using an AlN buffer layer grown at high temperature via MOVPE. Growth of smooth layers has been shown with the potential for device application. Atomic Force Microscopy showed submicron features and crystallographic terraces. High resolution X‐ray diffraction was used to study the crystallographic orientation of the epilayer with respect to the substrate. Anisotropies in the in‐plane structure were also revealed. The comparison with samples grown using conventional two‐step technology shows improved structural quality of the nonpolar GaN grown on the AlN buffer layer. Transmission electron microscope images showed that the microstructure of the a ‐GaN is dominated by stacking faults and threading dislocations, with density of 3.1 x 105 cm–1 and 1.2 x 1010 cm–2, respectively. A complex microstructure was revealed at the AlN/GaN interface, where roughness originates and smoothed out away from it. The low temperature photoluminescence spectrum shows band edge emission at 355 nm and two peaks at 360 nm and 375 nm, which are related to stacking faults. (© 2009 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Ti‐mask selective‐area growth of GaN nanorings by RF‐plasma‐assisted molecular‐beam epitaxy
Authors: Kouno Tetsuya , Kishino Katsumi , Sekiguchi Hiroto , Kikuchi Akihiko
Published: March 2009

GaN nanorings with InGaN/GaN multiple quantum wells (MQWs) were successfully fabricated on a GaN template by RF‐plasma‐assisted molecular‐beam epitaxy (RF‐MBE) using a titanium (Ti) mask selective‐area growth (SAG) technique. We employed focused ion beam (FIB) milling to make patterns on the Ti‐mask (ring groove patterns). 3‐period InGaN/GaN MQWs integrated into the GaN nanorings exhibited a clear room‐temperature photoluminescence (RT‐PL) spectrum with a peak wavelength of 462 nm and the full width at half maximum (FWHM) of the RT‐PL spectrum was 145 meV. In addition, we fabricated GaN double nanorings and hexagonal nanorings with InGaN/GaN MQWs by controlling the amount of FIB etching, and the growth conditions. (© 2009 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Pharmacokinetic interaction of single dose of piperine with steady‐state carbamazepine in epilepsy patients
Authors: Pattanaik Smita , Hota Debasish , Prabhakar Sudesh , Kharbanda Parampreet , Pandhi Promila
Published: March 2009

Piperine, the active principle of piper species, is commonly used as a spice and adjuvant in various traditional systems of medicine. It has been known as a bioavailability‐enhancer. The present study aimed at evaluating the effect of piperine on the steady‐state pharmacokinetics of a single dose of carbamazepine in poorly controlled epilepsy patients on carbamazepine monotherapy. Patients (n = 10 each) receiving either 300 mg or 500 mg dose of carbamazepine twice daily were selected. After administration of carbamazepine, venous blood samples were collected at 0, 0.5, 1, 2, 4, 6, 9, 12 h. Subsequently, piperine (20 mg p.o.) was administered along with carbamazepine and samples were collected similarly. The pharmacokinetic parameters were compared by Studentst‐test. Piperine significantly increased the mean plasma concentrations of carbamazepine at most of the time points in both dose groups. There was a significant increase inAUC0‐12hr(p< 0.001), averageCss(p< 0.001),t1\2el(p< 0.05) and a decrease inKel(p< 0.05), in both the dose groups, whereas changes inKaandt1\2awere not significant.Cmax(p< 0.01) andtmax(p< 0.01) were increased significantly following piperine administration in the 500 mg dose group; however, these parameters were not significant in the lower dose group. Piperine could significantly enhance the oral bioavailability of carbamazepine, possibly by decreasing the elimination and/or by increasing its absorption. Copyright © 2009 John Wiley & Sons, Ltd.
Proton affinity and enthalpy of formation of formaldehyde
Authors: Czakó Gábor , Nagy Balázs , Tasi Gyula , Somogyi Árpád , Šimunek Ján , Noga Jozef , Braams Bastiaan J. , Bowman Joel M. , Császár; Attila G.
Published: March 2009

The proton affinity and the enthalpy of formation of the prototypical carbonyl, formaldehyde, have been determined by the first‐principles composite focal‐point analysis (FPA) approach. The electronic structure computations employed the all‐electron coupled‐cluster method with up to single, double, triple, quadruple, and even pentuple excitations. In these computations the aug‐cc‐p(C)VXZ [X = 2(D), 3(T), 4(Q), 5, and 6] correlation‐consistent Gaussian basis sets for C and O were used in conjunction with the corresponding aug‐cc‐pVXZ (X = 2–6) sets for H. The basis set limit values have been confirmed via explicitly correlated computations. Our FPA study supersedes previous computational work for the proton affinity and to some extent the enthalpy of formation of formaldehyde by accounting for (a) electron correlation beyond the “gold standard” CCSD(T) level; (b) the non‐additivity of core electron correlation effects; (c) scalar relativity; (d) diagonal Born–Oppenheimer corrections computed at a correlated level; (e) anharmonicity of zero‐point vibrational energies, based on global potential energy surfaces and variational vibrational computations; and (f) thermal corrections to enthalpies by direct summation over rovibrational energy levels. Our final proton affinities at 298.15 (0.0) K are ΔpaHo (H2CO) = 711.02 (704.98) ± 0.39 kJ mol−1. Our final enthalpies of formation at 298.15 (0.0) K are ΔfHo (H2CO) = −109.23 (−105.42) ± 0.33 kJ mol−1. The latter values are based on the enthalpy of the H2 + CO → H2CO reaction but supported by two further reaction schemes, H2O + C → H2CO and 2H + C + O → H2CO. These values, especially ΔpaHo (H2CO), have better accuracy and considerably lower uncertainty than the best previous recommendations and thus should be employed in future studies. © 2009 Wiley Periodicals, Inc. Int J Quantum Chem, 2009
Acetone, butanone, pentanone, hexanone and heptanone in the headspace of aqueous solution and urine studied by selected ion flow tube mass spectrometry
Authors: Pysanenko Andriy , Wang Tianshu , Španěl Patrik , Smith David
Published: March 2009

Urine is commonly analysed in clinical practice by a variety of liquid‐phase techniques to check for excessive ketone bodies, proteins and salts to name just a few compounds. However, little work has been carried out to measure the volatile compounds emitted by urine since these do not yet have an established role in clinical diagnosis. There is, however, a growing body of evidence that these volatile compounds can be indicators of adverse physiological conditions and disease and with the advent of sensitive gas‐phase analytical methods they can be quickly quantified in urine headspace and potentially provide valuable support for clinical diagnosis. Thus, we are developing selected ion flow tube mass spectrometry, SIFT‐MS, for the real‐time analysis of urine headspace, ultimately to support rapid diagnosis in the clinical environment. In this paper we focus on volatile ketones in the headspace of aqueous solutions and urine donated by three healthy volunteers. Using SIFT‐MS, we have unambiguously quantified in urine headspace acetone, by far the most abundant ketone, butanone, pentanone, hexanone and heptanone using NO+ precursor ions. Further to this, we have determined the Henry's Law coefficients, HLC, for these ketones in aqueous solution to allow the liquid‐phase concentrations in urine to be estimated from headspace levels of their vapours. In addition, the influence of the addition of physiological amounts of dissolved urea, sodium chloride and hydrochloric acid on the partitioning of these ketones between the aqueous phase and gas phase has been investigated and found to be small, which gives greater credence to the use of the HLC obtained using aqueous solutions for the estimation of ketone concentrations in urine. Finally, parallel measurements of the levels of acetone in exhaled breath and urine headspace have been obtained and shown to be very similar, which gives support to the previous deduction from breath analysis that acetone is a truly systemic compound. Copyright © 2009 John Wiley & Sons, Ltd.
Stakeholder relations and the persistence of corporate financial performance
Authors: Choi Jaepil , Wang Heli
Published: March 2009

We examine the effect of a firm's relations with its nonfinancial stakeholders, including its employees, suppliers, customers, and communities, on the persistence of both superior and inferior financial performance. In particular, integrating and extending the resource‐based view of the firm and stakeholder management literatures, we develop the arguments that good stakeholder relations not only enable a firm with superior financial performance to sustain its competitive advantage for a longer period of time, but more importantly, also help poorly performing firms to recover from disadvantageous positions more quickly. The arguments are supported by the analysis of a series of first‐order autoregressive models. Our findings further suggest that the positive effect of good stakeholder relations on the persistence of superior performance is not as strong as that of some other firm resources, such as technological knowledge, but it is the only factor examined that promises to help a firm recover from inferior performance. Therefore, the role of positive stakeholder relations in helping poorly performing firms recover is found to be more critical than its role in helping superior firms sustain their performance advantage. Copyright © 2009 John Wiley & Sons, Ltd.
Block‐Copolymer Vesicles as Nanoreactors for Enzymatic Reactions
Authors: Chen Qi , Schönherr Holger , Vancso G. Julius
Published: March 2009

The impact of the spatial confinement of polystyrene‐block‐poly(acrylic acid) (PS‐b‐PAA) block copolymer (BCP) vesicles on the reactivity of encapsulated bovine pancreas trypsin is studied. Enzymes, as well as small molecules, are encapsulated with loading efficiencies up to 30% in BCP vesicles with variable internal volumes between 0.014 aL (internal vesicle diameter, din = 30 nm) and 8 aL (din = 250 nm), obtained by manipulating the vesicle preparation conditions. The kinetics of the trypsin‐catalyzed reaction of a fluorogenic substrate inside and outside the vesicles is quantitatively estimated using fluorescence spectroscopic analyses in conjunction with the use of NaNO2 as selective quencher for non‐encapsulated fluorophores. The values of the catalytic turnover number obtained for reactions in differently sized nanoscale reactors show a significant increase (up to ≈5×) with decreasing BCP vesicle volume, while the values of the Michaelis–Menten constant decrease. The observed increase in enzyme efficiency by two orders of magnitude compared to bulk solution is attributed to an enhanced rate of enzyme–substrate and molecule–wall collisions inside the nanosized reactors, as predicted in the literature on the basis of Monte Carlo simulations.
Epigenetic Landscaping During hESC Differentiation to Neural Cells
Authors: Golebiewska Anna , Atkinson Stuart P. , Lako Majlinda , Armstrong Lyle
Published: March 2009

The molecular mechanisms underlying pluripotency and lineage specification from embryonic stem cells (ESCs) are still largely unclear. To address the role of chromatin structure in maintenance of pluripotency in human ESCs (hESCs) and establishment of lineage commitment, we analyzed a panel of histone modifications at promoter sequences of genes involved in maintenance of pluripotency, self-renewal, and in early stages of differentiation. To understand the changes occurring at lineage-specific gene regulatory sequences, we have established an efficient purification system that permits the examination of two distinct populations of lineage committed cells; fluorescence activated cell sorted CD133+ CD45−CD34− neural stem cells and β-III-tubulin+ putative neurons. Here we report the importance of other permissive marks supporting trimethylation of Lysine 4 H3 at the active stem cell promoters as well as poised bivalent and nonbivalent lineage-specific gene promoters in hESCs. Methylation of lysine 9 H3 was found to play a role in repression of pluripotency-associated and lineage-specific genes on differentiation. Moreover, presence of newly formed bivalent domains was observed at the neural progenitor stage. However, they differ significantly from the bivalent domains observed in hESCs, with a possible role of dimethylation of lysine 9 H3 in repressing the poised genes.

Disclosure of potential conflicts of interest is found at the end of this article.