bluuebunny/crossref_metadata_2025 huggingface dataset:
Micro‐Raman investigation of terra sigillata slips: a comparative study of central Italian and southern Gaul productions
Authors: Leon Y. , Lofrumento C. , Zoppi A. , Carles R. , Castellucci E. M. , Sciau Ph.
Published: May 2010

Terra sigillata is certainly the most famous fine ware of the Roman period, and for this reason it has been a subject of interest for both the archeology and archeometry communities. X‐ray diffraction studies showed systematic differences in the mineral compositions between central Italian and south Gaul productions. All the slips contain hematite; the Gallic ones embody also a significant content of corundum, while the Italian productions contain a great proportion of spinel. Raman investigation fails to reveal directly these differences because the spectra are dominated by the hematite peaks. However, we originally demonstrate that, due to the occurrence of an upshift of bands, the Raman spectrum of these sigillata slips can be associated with a substituted hematite. This premise has been confirmed by comparing the crystallization of hematite in four annealed clays to that of the ancient slips. The results suggested that the presence of the strong additional Raman band at around 680 cm−1 present in both clays and ancient slips could be associated with the recrystallization of hematite, occurring above 750 °C. It could also be due to the magnetite content, but this hypothesis is not supported by X‐ray diffraction data. In addition, the reduction seems to take place only above 1050 °C, as suggested by the unveiling of hercynite as well as the darkening of the clay samples. Raman scattering is shown to be very sensitive to small variations in clays composition and to firing temperature, and it has been successfully used as an in situ sensitive probe for discriminating between Italian and south Gallic productions. Copyright © 2010 John Wiley & Sons, Ltd.
Randomized phase II study of gemcitabine plus radiotherapy versus gemcitabine, 5‐fluorouracil, and cisplatin followed by radiotherapy and 5‐fluorouracil for patients with locally advanced, potentially resectable pancreatic adenocarcinoma
Authors: Landry Jerome , Catalano Paul J. , Staley Charles , Harris Wayne , Hoffman John , Talamonti Mark , Xu Natalie , Cooper Harry , Benson Al B.
Published: May 2010

Purpose

A randomized phase II trial (E1200) was designed to assess toxicities and surgical resection rates in two neoadjuvant gemcitabine‐based chemoradiation regimens in patients with borderline resectable pancreatic cancer. The trial was terminated early due to poor accrual.

Patients and Methods

Patients with borderline resectable adenocarcinomas of the pancreas were enrolled. Arm A patients (n = 10) received gemcitabine 500 mg/m2 IV weekly for 6 weeks, with radiation to 50.4 Gy followed by surgical resection. Arm B patients (n = 11) received preoperative gemcitabine 175 mg/m2 on days 1, 5, 29, and 33, cisplatin 20 mg/m2 on days 1–5 and 29–32, 5‐FU 600 mg/m2 on days 1–5 and 29–32, followed by radiation with continuous infusion 5‐FU 225 mg/m2 for 6 weeks. All patients received adjuvant gemcitabine 1,000 mg/m2 weekly × 3 for five cycles.

Results

Three patients in arm A, and two patients in arm B were resected. Hematologic toxicity was comparable between the two arms except more patients in arm B developed grade 3 or 4 thrombocytopenia than those in arm A. Arm B had fewer grade 1‐2 GI toxicities although more patients (45%) experienced grade 3–4 GI toxicity.

Conclusions

This phase II trial showed that both regimens were tolerable, and resectability and survival were comparable to previous studies. J. Surg. Oncol. 2010; 101:587–592. © 2010 Wiley‐Liss, Inc.
Pelvis and extremity osteosarcoma with similar tumor volume have an equivalent survival
Authors: Song Won Seok , Cho Wan Hyeong , Jeon Dae‐Geun , Kong Chang‐Bae , Kim Min Suk , Lee Jun Ah , Shawky Eid Ahmed , Kim Jae‐Do , Lee Soo‐Yong
Published: May 2010

Background and Objectives

The poor prognosis of pelvic osteosarcoma is well recognized, but the cause of this prognosis has not been well defined.

Methods

We analyzed the clinicopathologic characteristics of pelvic osteosarcoma, and their prognostic significances in a cohort of 41 patients, treated either surgically by ablation or non‐surgically. In a separate case‐controlled study, the 20 surgically treated osteosarcoma patients were matched with 38 patients with extremity osteosarcoma by tumor volume and age.

Results

The 5‐year overall survival rates of the surgically and the non‐surgically treated pelvic osteosarcoma were 55.8 ± 13.0% and 4.8 ± 4.7%, respectively (P < 0.01). Non‐surgically managed pelvic osteosarcoma group were found to have a larger tumor volume (P = 0.02), bladder displacement and sacroiliac joint involvement (P < 0.01). The 5‐year metastasis free survival rates in the surgically treated pelvic and extremity osteosarcoma were no different (41.4 ± 12.8% vs. 48.6 ± 8.4%), and histologic responses to chemotherapy were similar in two groups.

Conclusions

No significant difference in survival or histologic response was found between the surgically treated pelvic and the extremity osteosarcoma with suitable tumor volume. Outcome of pelvis osteosarcoma corresponds to the poor survival of extremity osteosarcoma of high initial tumor burden. J. Surg. Oncol. 2010; 101:611–617. © 2010 Wiley‐Liss, Inc.
Preparation of molecular imprinted polymer with quaternary ammonium groups as recognition sites for separation of pig cyclophilin 18 and bovine serum albumin
Authors: Liu Huijuan , Han Ruifang , Feng Miao , Gao Junfei , Long Yi , Zhao Zhuo , Wang Ying , Mi Huaifeng
Published: May 2010

We introduce a new type of molecular imprinted polymer (MIP) with immobilized assistant recognition polymer chains (ARPCs) to create effective recognition sites. In this work, cloned pig cyclophilin 18 (pCyP18) and BSA were used as templates, respectively. The template protein was selectively assembled with ARPCs from the library which consists of numerous limited length polymer chains with randomly distributed recognition sites of the quaternary ammonium cationic groups and immobilizing sites. The assemblies of protein and ARPCs were adsorbed by macroporous microspheres and immobilized by cross‐linking polymerization. After removing the templates, the two kinds of synthesized MIPs were used to adsorb cloned pCyP18 and BSA from protein mixtures respectively and both showed high selectivity. It confirms that this new method is suitable to separate proteins of both low and high molecular weight. The extended experiment on adsorption of natural pCyP18 from cytosol shows that the obtained MIP using cloned protein as template can be used to enrich natural protein of low content.
Termination of pregnancy following prenatal diagnosis in France: how severe are the foetal anomalies?
Authors: Dommergues Marc , Mandelbrot Laurent , Mahieu‐Caputo Dominique , Boudjema Noel , Durand‐Zaleski Isabelle ,   and the ICI Group‐Club de médecine foetale
Published: May 2010

Objective

To determine how severe were the conditions leading to termination of pregnancy for foetal anomaly (TOPFA) in France.

Methods

Detailed indications for TOPFA were extracted from medical charts.

Results

Of 2465 completed records, indications were: chromosomal anomalies n = 963 (39.1%), malformations of a single organ without chromosomal or genetic aetiologies n = 898 (36.4%), multiple malformations without chromosomal or genetic aetiologies n = 238 (9.7%), obstetrical complications n = 161 (6.5%), non‐chromosomal genetic diseases n = 158 (6.4%), foetal infections n = 21 (0.9%), unexplained severe oligohydramnios n = 20 (0.8%), foetal exposure to teratogenic agents n = 6. Overall, 33.3% of anomalies were lethal (e.g. anencephaly), 25.2% were expected to result in isolated mental retardation (e.g. Down) and 35.1% in substantial handicap (e.g. myelomeningocele). In 6.4% of cases, the anomaly was either of late onset (e.g. Huntington's disease) or with uncertain prognosis (e.g. agenesis of corpus callosum) or severity was debatable (e.g. single limb agenesis, sickle cell disease).

Conclusions

Although there is no indisputable definition of which anomalies are ‘severe’, 93.6% of the decisions to terminate the pregnancy were made by women and professionals in reaction to anomalies which clearly were lethal or would lead to substantial physical and/or mental disabilities. Copyright © 2010 John Wiley & Sons, Ltd.
Comparative study of conducting polyaniline/copper and polyaniline/nickel composites in the presence of surfactants
Authors: Uygun Aysegul , Aslan Erhan
Published: May 2010

Polyaniline/copper and polyaniline/nickel composites were synthesized in the presence and absence of surfactants using ammonium persulfate as an initiator. The structural and surface characteristics of the composites were studied and compared using different techniques. The interfacial interactions and thermal stability of the composites were characterized using X‐ray diffraction and thermogravimetric analysis. Surface properties were investigated using scanning electron microscopy and energy‐dispersed X‐ray spectroscopy. The results indicate significant changes in the morphological and physicochemical properties of the composites when incorporating surfactants. The surfactant‐induced surface characteristics also have an effect on conductivity. Copyright © 2010 Society of Chemical Industry
Ventilatory parameters and maximal respiratory pressure changes with age in Duchenne muscular dystrophy patients
Authors: Gayraud Jerome , Ramonatxo Michele , Rivier François , Humberclaude Véronique , Petrof Basil , Matecki Stefan
Published: May 2010

The aim of this longitudinal study was to precise, in children with Duchenne muscular dystrophy, the respective functional interest of ventilatory parameters (Vital capacity, total lung capacity and forced expiratory volume in one second [FEV1]) in comparison to maximal inspiratory pressure (Pimax) during growth. In ten boys the mean age of 9.1 ± 1 years) to mean age of 16 ± 1.4 years followed over a period of 7 years, we found that: (1) ventilatory parameters expressed in percentage of predicted value, after a normal ascending phase, start to decrease between 11 and 12 years, (2) Pimax presented only a decreasing phase since the beginning of the study and thus was already at 67% of predicted value at 12 years while ventilatory parameters was still normal, (3) after 12 years the mean slopes of decrease per year of vital capacity and FEV1 were higher (10.7 and 10.4%) than that of Pimax (6.9%), (4) at 15 years mean values of vital capacity and FEV1 (53.3 and 49.5% of predicted values) was simlar to that of Pimax (48.3%). In conclusion, if at early stages of the disease, Pimax is a more reliable index of respiratory impaiment than ventilatory parameters, the follow‐up of ventilatory parameters, when they start to decrease, is a better indicator of disease progression and, at advanced stages they provided same information about the functional impact of disease. Pediatr Pulmonol. 2010; 45:552–559. © 2010 Wiley‐Liss, Inc.
Pulmonary exacerbations in cystic fibrosis with negative bacterial cultures
Authors: Zemanick Edith T. , Wagner Brandie D. , Harris J. Kirk , Wagener Jeffery S. , Accurso Frank J. , Sagel Scott D.
Published: May 2010

Background

Pulmonary exacerbations are a major cause of morbidity in cystic fibrosis (CF) and likely contribute to lung function decline. Exacerbations are often associated with characteristic airway bacteria [CF related bacteria (CFRB)]. However, some patients do not have CFRB detected by culture during exacerbations.

Objectives

We sought to determine the proportion of airway cultures negative for CFRB during pulmonary exacerbations, and to characterize patients who were CFRB‐negative versus CFRB‐positive.

Methods

We performed a retrospective study of patients with CF admitted for a pulmonary exacerbation. Patients were classified as CFRB‐positive or CFRB‐negative based on admission airway cultures. Demographics, clinical presentation, lung function, history of chronic Pseudomonas aeruginosa infection and improvement in lung function with treatment were compared between groups.

Main Results

There were 672 admissions for exacerbation involving 211 patients over 5 years. Seventeen percent were classified as CFRB‐negative. Forty‐one percent of bronchoalveolar lavage (BAL), 32% of throat and 10% of sputum samples were CFRB‐negative. Among patients capable of expectorating sputum, the CFRB‐negative group was younger, less likely to have chronic P. aeruginosa, had higher lung function and body mass index (BMI), and had a lower systemic inflammatory response on admission compared to those with CFRB‐positive cultures. The two groups had similar numbers of patients with three or more signs and symptoms of a pulmonary exacerbation (88% vs. 92%). Both groups returned to baseline lung function following treatment.

Conclusions

A significant number of patients with CF and pulmonary exacerbation did not have typical CFRB detected by culture. Patients without CFRB still had characteristic signs and symptoms of pulmonary exacerbation and responded to treatment. Understanding the causes of illness in these patients may improve the diagnosis and treatment of pulmonary exacerbations in CF. Pediatr Pulmonol. 2010; 45:569–577. © 2010 Wiley‐Liss, Inc.
Role of emerging respiratory viruses in children with severe acute wheezing
Authors: García‐García M.L. , Calvo C. , Falcón A. , Pozo F. , Pérez‐Breña P. , De Cea J.M. , Casas I.
Published: May 2010

Background

Acute wheezing episodes are frequently associated with respiratory viral infections in children. However, the role of the recently described respiratory viruses is not yet fully understood.

Objective

The main objective of this study was to estimate the frequency of human metapneumovirus (HMPV), human bocavirus (HBoV), and 14 other respiratory viruses in hospitalized children with acute wheezing.

Methods

A prospective study was conducted on children <14 years old, admitted with an acute expiratory wheezing episode from September 2005 to June 2008. Viruses were detected in nasopharyngeal aspirates by polymerase chain reaction. Clinical data were prospectively recorded.

Results

A viral pathogen was identified in 444 (71%) out of 626 hospitalized acute wheezing episodes. Respiratory syncytial virus (RSV) was the most frequently detected (27%), followed by rhinovirus (24%), adenovirus (17.8%), HBoV (16%), and HMPV (4.7%). The rate of viral detection was significantly higher in infants (77.3%), than in older children (59.8%) (P < 0.001). RSV and HBoV were more prevalent in infants (P < 0.001) than in older children.

Conclusion

The most prevalent viruses found in severe acute wheezing episodes were RSV and rhinovirus not only in childhood, but also in infancy. However, other emerging viruses such as HBoV and metapneumovirus also play an important role in wheezing episodes. Pediatr Pulmonol. 2010; 45:585–591. © 2010 Wiley‐Liss, Inc.
Pulmonary thromboendarterectomy in adolescents and young adults
Authors: Johnson Jonathan N. , Driscoll David J. , McGregor Christopher G.A.
Published: May 2010

Objectives

Chronic thromboembolic pulmonary hypertension (CTEPH) occurs in patients with recurrent or chronic pulmonary embolism, and is a rare but potentially devastating disease in adolescents and young adults. Pulmonary thromboendarterectomy (PTE) is an important curative therapy for patients with CTEPH. The importance of this treatment may be under‐appreciated and under‐utilized in adolescents and young adults.

Study Design

We performed a chart review of all patients <24 years of age who had PTE performed for CTEPH at our institution from 2003–2009 (seven patients, average age 20.2 ± 2.5 years, range 17–23 years, average BMI 34 ± 12 kg/m2). All patients had their operations performed by a single surgeon.

Results

There were no deaths. Three of the seven patients were incorrectly diagnosed prior to the diagnosis of CTEPH. Right ventricular systolic pressure decreased from 61.3 ± 19 mmHg pre‐operatively to 31.8 ± 5 mmHg post‐operatively (P = 0.008). All patients reported symptomatic relief, and no patient has had recurrence of CTEPH.

Conclusion

Although rare in the young patient, recurrent pulmonary emboli can have devastating consequences. The potentially lethal implications of CTEPH may be under‐appreciated in adolescents and young adults. When indicated, PTE is a definitive, curative procedure with low morbidity and mortality. Pediatr Pulmonol. 2010; 45:614–618. © 2010 Wiley‐Liss, Inc.
Baseline sensitivity of lepidopteran corn pests in India to Cry1Ab insecticidal protein of Bacillus thuringiensis
Authors: Jalali Sushil K , Lalitha Yadavalli , Kamath Subray P , Mohan Komarlingam S , Head Graham P
Published: May 2010

BACKGROUND: Genetically engineered corn (Bt corn) expressing Bacillus thuringiensis Berliner insecticidal protein Cry1Ab is a biotechnological option being considered for management of lepidopteran corn pests in India. As a resistance management practice it was essential to determine the sensitivity of multiple populations of the stalk borer Chilo partellus (Swinhoe), pink borer Sesamia inferens (Walker) and the cob borer Helicoverpa armigera (Hübner) to Cry1Ab protein through bioassays. The insect populations were collected during growing seasons of Rabi 2005 (October 2005 to February 2006) and Kharif 2006 (May to September 2006).

RESULTS: Multiple populations of the three lepidopteran corn pests were found to be susceptible to Cry1Ab. Median lethal concentrations (LC50) ranged between 0.008 and 0.068 µg Cry1Ab mL−1 diet for 18 populations of C. partellus (across two seasons), between 0.12 and 1.99 µg mL−1 for seven populations of H. armigera and between 0.46 and 0.56 µg mL−1 for two populations of S. inferens.

CONCLUSION: Dose–response concentrations for lethality and growth inhibition have been determined to mark baseline sensitivity of multiple populations of key lepidopteran corn pests in India to Cry1Ab protein. These benchmark values will be referenced while monitoring resistance to Cry1Ab should Bt corn hybrids expressing Cry1Ab be approved for commercial cultivation in India. Copyright © 2010 Society of Chemical Industry
Carrier dynamics in GaN layers overgrown on nanocolumnar structures
Authors: Wang Hsiang‐Chen , Tang Tung‐Yi , Yang C. C. , Malinauskas T. , Jarašiūnas K.
Published: May 2010

We report on photoelectrical and optical properties of the GaN layers overgrown on the columnar structure with diameter of columns varying from 250 to 600 nm. Excess carriers were injected to 2‐μm thick overgrown layer by an interference pattern of two picosecond laser beams at 355 nm. Carrier recombination and diffusion was monitored by time‐resolved transient grating technique and provided 3‐4 fold increase of carrier lifetime (up to ∼500 ps) with respect to that in the GaN template. Even stronger increase of carrier lifetime at excess carrier density of ∼1019 cm‐3 was observed both in the overgrown layers and substrate and attributed to saturation of electron trapping centers by free carriers. A factor of 7‐8 stronger time‐integrated photoluminescence intensity (at 363 nm) also confirmed the increased structural quality of the overgrown layers, what correlated well with the enhanced electrical parameters (© 2010 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Study of Si implantation into Mg‐doped GaN for MOSFETs
Authors: Ostermaier Clemens , Ahn Sang‐Il , Potzger Kay , Helm Manfred , Kuzmik Jan , Pogany Dionyz , Strasser Gottfried , Lee Jong‐Ho , Hahm Sung‐Ho , Lee Jung‐Hee
Published: May 2010

In this paper we focus on activation and diffusion during annealing of silicon after implantation into Mg‐doped GaN epitaxial layers. The Si diffusion was analyzed for different capping materials and compared to an uncapped sample. Investigation of the Si concentration obtained from secondary ion mass spectroscopy (SIMS) and comparison with calculation revealed several diffusion constants. Different diffusion behaviours at the surface were detected for different Si concentrations around the solubility of Si in GaN. Further, we found similar Si activation efficiencies in GaN for high and low fluences, after taking into account the compensation of electrons by the p‐type background doping. In addition, we investigated the insulation between Si implanted islands in p‐type GaN and the effect of additional Ar+ implantation. (© 2010 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Photoluminescence and photoluminescence excitation spectra from AlN doped with Gd3+
Authors: Fukui Kazutoshi , Sawai Syun , Ito Tomoharu , Emura Shuichi , Araki Tsutomu , Suzuki Akira
Published: May 2010

The photoluminescence (PL) spectra from Al0.98Gd0.02N and Al0.87Gd0.13N consisting of Gd3+ related 3.95 eV sharp emission lines and other bands, and the PL excitation (PLE) spectra from 3 to 7 eV have been investigated by using a highly linear polarized synchrotron radiation light source. The Gd related 3.95 eV sharp lines in the PL spectra are similar to those in other cathodoluminescence (CL) and PL research works. However, the broad emission bands around 3.95 eV lines which are normally found in other CL works are not observed. Other broad emission bands are clearly observed in the energy region of 1.5 ∼ 3.5 eV. PLE spectra monitored at both the 3.95 eV sharp line and the broad emission band of Al0.98Gd0.02N clearly indicate that these emission processes are host excitations which are reflected by an AlN‐like band structure and crystalline anisotropy. On the other hand, the PLE and optical reflectance spectra of Al0.87Gd0.13N reveal an unclear band structure with a long band tail to in the lower energy side (© 2010 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
A cost‐based selective maintenance decision‐making method for machining line
Authors: Zhu Haiping , Liu Fanmao , Shao Xinyu , Liu Qiong , Deng Yuhao
Published: May 2010

Machine line is a type of manufacturing system in which machines are connected in series or in parallel. It is significant to ensure the reliability as well as to reduce the total cost of maintenance and failure losses in the maintenance programs of such systems. Cost‐based selective maintenance decision‐making, which is the best method for a selected group of machines in machine line is presented under limited maintenance durations. Fault losses and maintenance costs of a single machine under different maintenance actions i.e. minimal repair, preventive maintenance and overhaul on the fault rate of the machine are calculated. An algorithm combining the heuristic rules and tabu search is proposed to solve the presented selective maintenance model. Finally, a case study on the maintenance decision‐making problem of a connecting rod machining line in the automobile engine workshop is presented to illustrate the applicability of the proposed method. The end result shows that the fault losses can be further reduced by the optimization of maintenance interval and maintenance duration. Copyright © 2010 John Wiley & Sons, Ltd.
Combining degradation and contact angle data in assessing the photocatalytic TiO2:N surface
Authors: Manole Alina , Dǎscǎleanu V. , Dobromir M. , Luca D.
Published: May 2010

Increasing the oxidative efficiency of titania by a better use of photoactivation energy from visible solar light has been the subject of major interest during the last decades. Doping titania materials with metals and nonmetals has been demonstrated as a means to enhancing the photocatalytic and hydrophilicity performances by shifting the optical absorption edge of the materials towards visible range. However, when using plasma vapor deposition techniques for film synthesis, incorporating higher amounts of certain dopants (such as nitrogen), in the films from the gas phase is less effective due to low affinity of Ti for them. Alternative means for trimming the N/O content ratio in the films remained an open issue till now.

We propose here, a versatile new approach to synthesize TiO2:N thin films of controllable elemental composition by using a sintered TiN target as material source in a reactive RF discharge within the ArO2 gas mixture. By adjusting the O2 partial pressure between 4.2 × 10−6 mbar and 1.3 × 10−3 mbar, RF sputtered thin films have been prepared with N atomic concentration varying between 1.2–1.8 at.%. Film surface morphology, crystallinity, elemental composition and oxidation state data were inferred from AFM, XRD and XPS measurements. Large differences of atomic concentrations of the main elements in the surface have been found between the as‐deposited and sputter‐cleaned films, due to the effect of Ar+ ion bombardment. The rate constants of photoinduced hydrophilic conversion of the TiO2:N surface was inferred from water contact angle data taken during both surface activation and back‐reaction time. The oxidative performance of the photocatalytic films was investigated using oleic acid (C18H34O2) as a test material. The results were discussed in terms of the effects of elemental composition, surface morphology and electronic structure of the films. Copyright © 2010 John Wiley & Sons, Ltd.
Selective Chemical Modification of Graphene Surfaces: Distinction Between Single‐ and Bilayer Graphene
Authors: Koehler Fabian M. , Jacobsen Arnhild , Ensslin Klaus , Stampfer Christoph , Stark Wendelin J.
Published: May 2010

Graphene modifications with oxygen or hydrogen are well known in contrast to carbon attachment to the graphene lattice. The chemical modification of graphene sheets with aromatic diazonium ions (carbon attachment) is analyzed by confocal Raman spectroscopy. The temporal and spatial evolution of surface‐adsorbed species allows accurate tracking of the chemical reaction and identification of intermediates. The controlled transformation of sp2 to sp3 carbon proceeds in two separate steps. The presented derivatization is faster for single‐layer graphene and allows controlled transformation of adsorbed diazonium reagents into covalently bound surface derivatives with enhanced reactivity at the edge of single‐layer graphene. On bilayer graphene the derivatization proceeds to an adsorbed intermediate, which reacts slower to a covalently attached species on the carbon surface.
Tearing Graphene Sheets From Adhesive Substrates Produces Tapered Nanoribbons
Authors: Sen Dipanjan , Novoselov Kostya S. , Reis Pedro M. , Buehler Markus J.
Published: May 2010

Graphene is a truly two‐dimensional atomic crystal with exceptional electronic and mechanical properties. Whereas conventional bulk and thin‐film materials have been studied extensively, the key mechanical properties of graphene, such as tearing and cracking, remain unknown, partly due to its two‐dimensional nature and ultimate single‐atom‐layer thickness, which result in the breakdown of conventional material models. By combining first‐principles ReaxFF molecular dynamics and experimental studies, a bottom‐up investigation of the tearing of graphene sheets from adhesive substrates is reported, including the discovery of the formation of tapered graphene nanoribbons. Through a careful analysis of the underlying molecular rupture mechanisms, it is shown that the resulting nanoribbon geometry is controlled by both the graphene–substrate adhesion energy and by the number of torn graphene layers. By considering graphene as a model material for a broader class of two‐dimensional atomic crystals, these results provide fundamental insights into the tearing and cracking mechanisms of highly confined nanomaterials.
BMP Signaling in the Human Fetal Ovary is Developmentally Regulated and Promotes Primordial Germ Cell Apoptosis
Authors: Childs Andrew J. , Kinnell Hazel L. , Collins Craig S. , Hogg Kirsten , Bayne Rosemary A.L. , Green Samira J. , McNeilly Alan S. , Anderson Richard A.
Published: May 2010

Primordial germ cells (PGCs) are the embryonic precursors of gametes in the adult organism, and their development, differentiation, and survival are regulated by a combination of growth factors collectively known as the germ cell niche. Although many candidate niche components have been identified through studies on mouse PGCs, the growth factor composition of the human PGC niche has not been studied extensively. Here we report a detailed analysis of the expression of components of the bone morphogenetic protein (BMP) signaling apparatus in the human fetal ovary, from postmigratory PGC proliferation to the onset of primordial follicle formation. We find developmentally regulated and reciprocal patterns of expression of BMP2 and BMP4 and identify germ cells to be the exclusive targets of ovarian BMP signaling. By establishing long-term cultures of human fetal ovaries in which PGCs are retained within their physiological niche, we find that BMP4 negatively regulates postmigratory PGC numbers in the human fetal ovary by promoting PGC apoptosis. Finally, we report expression of both muscle segment homeobox (MSX)1 and MSX2 in the human fetal ovary and reveal a selective upregulation of MSX2 expression in human fetal ovary in response to BMP4, suggesting this gene may act as a downstream effector of BMP-induced apoptosis in the ovary, as in other systems. These data reveal for the first time growth factor regulation of human PGC development in a physiologically relevant context and have significant implications for the development of cultures systems for the in vitro maturation of germ cells, and their derivation from pluripotent stem cells.
Efficient and rational spectrum utilization in opportunistic OFDMA networks with imperfect CSI: a utility‐based top‐down approach
Authors: Bogucka Hanna
Published: May 2010

In this paper, we consider the Orthogonal Frequency Division Multiple Access (OFDMA)‐based Opportunistic Radio (OR) networks, in which the nodes are able to adopt a subset of subcarriers (SCs) available in the considered network area, as well as the transmission rate and power associated with these SCs either for their uplink or downlink transmission. The idea of our top‐down approach to the efficient and rational spectrum utilization is to allow each node to first optimize the resources acquisition at OSI‐layer 2 (top), where the competition of nodes for available common resources is observed, and then to autonomously optimize the transmission parameters accounting for the radio channel conditions at the physical (down) layer. We assume that the nodes act independently based on their local channel quality information, which contains an error. In these optimization tasks, the efficiency and rationality mechanisms have been introduced in the objective (utility) functions, which reflect the throughput achieved, the network potential to serve multiple nodes, as well as pricing of resources and the power economy. Copyright © 2010 John Wiley & Sons, Ltd.
Collaborative spectrum sensing in the presence of secondary user interferences for lognormal shadowing
Authors: Chen Yunfei
Published: May 2010

The performance of collaborative spectrum sensing is examined for lognormal shadowing channels when secondary user interferences (SUIs) occur. Both soft decision rule and hard decision rule are considered. Computer simulation shows that the SUIs can be ignored in some cases, depending on the signal‐to‐noise ratio (SNR), the signal‐to‐interference ratio, the number of secondary users, the sample correlation, and the decision rule. Thus, by choosing appropriate system parameters, one may conduct collaborative spectrum sensing at the same time as secondary data transmission to save overheads. Copyright © 2010 John Wiley & Sons, Ltd.
Posttranscriptional control and the role of RNA‐binding proteins in gene regulation in trypanosomatid protozoan parasites
Authors: Fernández‐Moya Sandra M. , Estévez Antonio M.
Published: May 2010

Trypanosomatids are unicellular eukaryotes responsible for severe diseases in humans. They exhibit a number of remarkable biological phenomena, especially at the RNA level. During their life cycles, they alternate between a mammalian host and an insect vector and undergo profound biochemical and morphological transformations in order to adapt to the different environments they find within one or the other host species. These changes are orchestrated by specific gene expression programs. In contrast to other organisms, trypanosomatids do not regulate RNA polymerase II‐dependent transcription initiation. Evidence so far indicates that the main control points in gene expression are mRNA degradation and translation. Recent studies have shown that RNA‐binding proteins (RBPs) play a critical role in the developmental regulation of mRNA and protein abundance. RBPs seem to bind to specific subsets of mRNAs encoding functionally related proteins. These ribonucleoprotein complexes may represent posttranscriptional operons or regulons that are able to control the fate of multiple mRNAs simultaneously. We suggest that trypanosomatids transduce environmental signals into mRNA and protein abundance through posttranslational modification of RBPs. Copyright © 2010 John Wiley & Sons, Ltd.

This article is categorized under:

RNA Interactions with Proteins and Other Molecules > Protein‐RNA Interactions: Functional Implications

RNA in Disease and Development > RNA in Disease
The relationship of prions and translation
Authors: Wickner Reed B. , Edskes Herman K. , Shewmaker Frank P. , Kryndushkin Dmitry , Nemecek Julie , McGlinchey Ryan , Bateman David
Published: May 2010

Prions are infectious proteins, without the need for an accompanying nucleic acid. Nonetheless, there are connections of prions with translation and RNA, which we explore here. Most prions are based on self‐propagating amyloids. The yeast [PSI+] prion is an amyloid of Sup35p, a subunit of the translation termination factor. The normal function of the Sup35p prion domain is in shortening the 3′ polyA of mRNAs and thus in mRNA turnover. The [ISP+] prion is so named because it produces antisuppression, the opposite of the effect of [PSI+]. Another connection of prions with translation is the influence on prion propagation and generation of ribosome‐associated chaperones, the Ssbs, and a chaperone activity intrinsic to the 60S ribosomal subunits. Copyright © 2010 John Wiley & Sons, Ltd.

This article is categorized under:

Translation > Translation Mechanisms

Translation > Translation Regulation
Optic neuropathy in methylmalonic acidemia: the role of neuroprotection
Authors: Pinar‐Sueiro Sergio , Martínez‐Fernández Ricardo , Lage‐Medina Sergio , Aldamiz‐Echevarria Luis , Vecino Elena
Published: May 2010

We report the case of a patient with an optic neuropathy induced by neurotoxicity in the setting of methylmalonic acidemia. The patient responded with a significant and long‐term improvement in visual acuity, perimetry, and chromatic function after a neuroprotective treatment with vitamin E and coenzyme Q10 was started. Coenzyme Q10 levels had been proven to be normal before starting treatment. This case report is particularly important because it describes a possible treatment for optic neuropathy in methylmalonic patients. Although the response might be, in part, specific to the individual, it suggests the existence of a cause–effect relationship between the treatment undergone by our patient and the improvement in her visual acuity. To date, no other treatments with beneficial effects have been reported for the few optic neuropathies caused by methylmalonic acidemia. Further studies should determine the applicability of coenzyme Q10 and vitamin E for the treatment of optic neuropathies in methylmalonic acidemia.
Surface Properties and Thermodynamic Parameters of Some Sugar‐Based Ethoxylated Amine Surfactants: 1—Synthesis, Characterization, and Demulsification Efficiency
Authors: Abdel‐Raouf Manar El‐Sayed , Abdul‐Raheim Abdul‐Raheim Mahmoud , Abdel‐Azim Abdel‐Azim Ahmed
Published: May 2010

Several ethoxylated sugar‐based amine surfactants have been synthesized and characterized by IR and 1HNMR spectroscopy. The surface activity of the prepared compounds has been thoroughly studied and some of their surface properties (such as CMC, Γmax, and Amin) have been calculated. The surface properties of the prepared compounds were correlated to their chemical structure. It was found that CMC decreases when increasing the molecular weight of polyethylene glycols, whereas Amin increases. Furthermore, the thermodynamic parameters of adsorption and micellization were also calculated. They include ΔG, ΔH, and ΔS of micellization and adsorption. The data show that the synthesized surfactants favor adsorption, so that they can be used as demulsifiers for crude oil emulsions. In this respect, the demulsification test was carried out and the results of demulsification efficiency were correlated to the chemical composition of the investigated compounds. Some factors that affect the demulsification efficiency were also considered.
“Managing Up” Can Improve Teamwork in the OR
Authors: Smith Sandra Lee
Published: May 2010

Holding each team member accountable for following policies and behaving professionally in the work environment should be the responsibility of all perioperative personnel, not just the department manager. A culture in which employees “manage up” is one in which they communicate with each other in respectful ways and feel comfortable correcting each other when they see negative behaviors or inconsistencies in patient care delivery. Creating a culture in which employees feel empowered to manage up requires education, support of management, and staff member assertiveness. Ultimately, individual accountability and effective teamwork can help ensure patient safety.
Adherence to a Medication Safety Protocol: Current Practice for Labeling Medications and Solutions on the Sterile Field
Authors: Brown‐Brumfield Diana , DeLeon Agripina
Published: May 2010

Medication labeling omissions in the OR and the adverse events that result from them remain a challenge in health care facilities. Standardization of protocols based on guidance from the Joint Commission, AORN, the Institute for Safe Medication Practices, and other organizations is important to ensure that patients do not mistakenly receive the wrong medication. A clinical nurse specialist and a perioperative education coordinator at the Cleveland Clinic, Cleveland, Ohio, undertook a direct observation quality improvement project to assess the adherence of 21 nurses and 19 surgical technologists to a revised medication and solution labeling protocol implemented in February 2008. Results showed that overall, 70% of staff members adhered to the medication and solution labeling protocol but adherence varied among specialty areas. There was increased adherence to the protocol by junior staff members compared with more experienced staff members.
Tracing the tumor lineage
Authors: Navin Nicholas E. , Hicks James
Published: May 2010

Defining the pathways through which tumors progress is critical to our understanding and treatment of cancer. We do not routinely sample patients at multiple time points during the progression of their disease, and thus our research is limited to inferring progression a posteriori from the examination of a single tumor sample. Despite this limitation, inferring progression is possible because the tumor genome contains a natural history of the mutations that occur during the formation of the tumor mass. There are two approaches to reconstructing a lineage of progression: (1) inter‐tumor comparisons, and (2) intra‐tumor comparisons. The inter‐tumor approach consists of taking single samples from large collections of tumors and comparing the complexity of the genomes to identify early and late mutations. The intra‐tumor approach involves taking multiple samples from individual heterogeneous tumors to compare divergent clones and reconstruct a phylogenetic lineage. Here we discuss how these approaches can be used to interpret the current models for tumor progression. We also compare data from primary and metastatic copy number profiles to shed light on the final steps of breast cancer progression. Finally, we discuss how recent technical advances in single cell genomics will herald a new era in understanding the fundamental basis of tumor heterogeneity and progression.
Etiology and one‐year follow‐up results of hearing loss identified by screening of newborn hearing in Japan
Authors: Adachi Nodoka , Ito Ken , Sakata Hideaki , Yamasoba Tatsuya
Published: May 2010

Objective

To evaluate the incidence of newborn hearing loss in a Japanese population and to elucidate etiological factors and one‐year prognosis.

Study Design

Screening of newborn hearing.

Setting

Children's tertiary referral center.

Subjects and Methods

Between 1999 and 2008, 101,912 newborn infants were screened, with 693 infants (0.68%) referred. Etiology investigation included CT, detection of cytomegalovirus (CMV) DNA, and connexin 26 mutation.

Results

Abnormal results (auditory brainstem response [ABR] threshold ≥ 35 normal hearing level [dB nHL] in either side) were observed in 312 infants (0.31%), and 133 subjects (0.13%) with ABR thresholds ≥ 50 dB nHL on both sides were classified into the habilitation group. In this group, inner ear/internal auditory meatus anomalies were detected in 20 of 121 subjects (17%) tested, middle/external ear anomalies in 14 of 121 subjects (12%), CMV DNA in 13 of 77 subjects (17%), and connexin 26 mutation in 28 of 89 subjects (31%). In 68 subjects undergoing all three investigations (CT, CMV, and connexin 26), 41 (60%) had positive results in at least one test. With inclusion of otitis media with effusion and perinatal problems, this rate amounted to 78% (53 subjects). Of the 97 infants in the habilitation group successfully followed up to one year, 36 (37%) showed a threshold change of 20 dB or more in either ear: 11 (11%) progression and 25 (26%) improvement, and 15 infants (15%) were reclassified into a less severe classification.

Conclusion

Considering that 26 percent of infants with bilateral moderate to severe hearing loss showed improvement in one year, habilitation protocols, especially very early cochlear implantation within one year of birth, should be reconsidered.
The NEURON Book
Authors: Carnevale Nicholas T. , Hines Michael L.
Published: May 2010

The authoritative reference on NEURON, the simulation environment for modeling biological neurons and neural networks that enjoys wide use in the experimental and computational neuroscience communities. This book shows how to use NEURON to construct and apply empirically based models. Written primarily for neuroscience investigators, teachers, and students, it assumes no previous knowledge of computer programming or numerical methods. Readers with a background in the physical sciences or mathematics, who have some knowledge about brain cells and circuits and are interested in computational modeling, will also find it helpful. The NEURON Book covers material that ranges from the inner workings of this program, to practical considerations involved in specifying the anatomical and biophysical properties that are to be represented in models. It uses a problem-solving approach, with many working examples that readers can try for themselves.
GENDER IDEOLOGY, SAME-SEX PEER GROUP AFFILIATION AND THE RELATIONSHIP BETWEEN TESTOSTERONE AND DOMINANCE IN ADOLESCENT BOYS AND GIRLS
Authors: VERMEERSCH HANS , T'SJOEN GUY , KAUFMAN J. M. , VINCKE J. , VAN HOUTTE MIEKE
Published: May 2010

Although the role of testosterone in the aetiology of social dominance is often suggested, surprisingly few studies have addressed the relationship between sex steroid hormones and dominance as a personality trait. In this paper, the relationship between testosterone and dominance is studied in a sample of adolescent boys and girls, taking into account the moderating role of gender ideology and same-sex peer group orientation. A direct association between free testosterone (FT) and dominance was found in girls but not in boys. In boys, masculine ideology moderated the relationship between FT and dominance, while in girls the relationship between FT and dominance was moderated by same-sex peer group affiliation.
Molluscicidal and ovicidal activities of plant extracts of the Piperaceae on Biomphalaria glabrata (Say, 1818)
Authors: Rapado L.N. , Nakano E. , Ohlweiler F.P. , Kato M.J. , Yamaguchi L.F. , Pereira C.A.B. , Kawano T.
Published: May 2010

Schistosomiasis is a tropical disease caused by Schistosoma and occurs in 54 countries, mainly in South America, the Caribbean region, Africa and the eastern Mediterranean. Currently, 5 to 6 million Brazilian people are infected and 30,000 are under infection risk. Typical of poor regions, this disease is associated with the lack of basic sanitation and very frequently to the use of contaminated water in agriculture, housework and leisure. One of the most efficient methods of controlling the disease is application of molluscicides to eliminate or to reduce the population of the intermediate host snail Biomphalaria glabrata. Studies on molluscicidal activity of plant extracts have been stimulated by issues such as environmental preservation, high cost and recurrent resistance of snails to synthetic molluscicides. The aim of this study was to determine the molluscicide action of extracts from Piperaceae species on adult and embryonic stages of B. glabrata. Fifteen extracts from 13 Piperaceae species were obtained from stems, leaves and roots. Toxicity of extracts was evaluated against snails at two different concentrations (500 and 100 ppm) and those causing 100% mortality at 100 ppm concentration were selected to obtain the LC90 (lethal concentration of 90% mortality). Piper aduncum, P. crassinervium, P. cuyabanum, P. diospyrifolium and P. hostmannianum gave 100% mortality of adult snails at concentrations ranging from 10 to 60 ppm. These extracts were also assayed on embryonic stages of B. glabrata and those from P. cuyabanum and P. hostmannianum showed 100% ovicidal action at 20 ppm.
Ageing, social class and common mental disorders: longitudinal evidence from three cohorts in the West of Scotland
Authors: Green M. J. , Benzeval M.
Published: May 2010

Background

Understanding how common mental disorders such as anxiety and depression vary with socio-economic circumstances as people age can help to identify key intervention points. However, much research treats these conditions as a single disorder when they differ significantly in terms of their disease burden. This paper examines the socio-economic pattern of anxiety and depression separately and longitudinally to develop a better understanding of their disease burden for key social groups at different ages.

Method

The Twenty-07 Study has followed 4510 respondents from three cohorts in the West of Scotland for 20 years and 3846 respondents had valid data for these analyses. Hierarchical repeated-measures models were used to investigate the relationship between age, social class and the prevalence of anxiety and depression over time measured as scores of 8 or more out of 21 on the relevant subscale of the Hospital Anxiety and Depression Scale (HADS).

Results

Social class differences in anxiety and depression widened with age. For anxiety there was a nonlinear decrease in prevalence with age, decreasing more slowly for those from manual classes compared to non-manual, whereas for depression there was a non-linear increase in prevalence with age, increasing more quickly for those from manual classes compared to non-manual. This relationship is robust to cohort, period and attrition effects.

Conclusions

The more burdensome disorder of depression occurs more frequently at ages where socio-economic inequalities in mental health are greatest, representing a ‘double jeopardy’ for older people from a manual class.