bluuebunny/crossref_metadata_2025 huggingface dataset:
Isothermal crystallization study on a biodegradable segmented copolymer constituted by glycolide and trimethylene carbonate units
Authors: Díaz‐Celorio Elena , Franco Lourdes , Puiggalí Jordi
Published: December 2009

The isothermal crystallization behavior of a segmented copolymer constituted by hard blocks of polyglycolide and soft segments derived from the copolymerization of glycolide and trimethylene carbonate was investigated. This polymer has applied relevance because it is one of the most widely used for bioabsorbable surgical sutures. Calorimetric, optical microscopy, and infrared techniques were combined to understand the thermal properties and the different factors that influence the crystallization process. Basically, only the hard blocks crystallized, although certain processing conditions allowed performing an additional crystallization associated with small lamellar domains of the soft segment. Crystallization from both the melt and the glass state rendered positive spherulites with a fibrillar texture. The observed unusual sign of birefringence was a consequence of the close packing structure of polyglycolide, which was also corroborated by electron diffraction patterns. Crystallization was characterized by an athermal nucleation, which allowed accurate estimation of the secondary nucleation parameter by using the calorimetric data only. Significant differences in the Avrami exponent (from 2.32 to 1.45) were found between the cold and hot isothermal crystallizations. The stronger geometric constraints observed in the crystallization from the glass state were also corroborated by FTIR analyses. © 2009 Wiley Periodicals, Inc. J Appl Polym Sci, 2010
Moisture effect on deformability of epoxy/montmorillonite nanocomposite
Authors: Glaskova T. , Aniskevich A.
Published: December 2009

In this article the moisture effect on deformability of epoxy/montmorillonite nanocomposite was investigated. The change of fracture character and drop of elastic characteristics due to moisture absorption was observed. The estimation of filler morphological peculiarities (platelet stack constitution) in composite and its effect on nanocomposite elastic properties was undertaken. It is shown that the higher number of filler platelet per stack consistently leads to the decrease of nanocomposite elastic properties. Nevertheless prediction by micromechanical model is rough for moistened nanocomposite because of resin structural changes. © 2009 Wiley Periodicals, Inc. J Appl Polym Sci, 2010
Maleic anhydride grafted polyethylene powder coated with epoxy resin: A novel reactive hot melt adhesive
Authors: Ha Thu Huong , Jang Jin Young , Cho Youn Bok , Jeong Han Mo , Kim Byung Kyu
Published: December 2009

A novel reactive hot melt adhesive was prepared by coating an epoxy resin on maleic anhydride grafted polyethylene (MAPE) powder. This adhesive had markedly improved adhesion power compared with pristine MAPE powder, which is normally used as a hot melt adhesive. The generation of an ester linkage by the reaction between the anhydride group of MAPE and the hydroxyl group of epoxy resin, during the bonding operation at 190°C with the pressure of 22 MPa for 30 min, was confirmed from the FTIR spectra. The bond strength was further improved by a small amount of 1‐methylimidazole, which accelerated the esterification reaction. When the epoxy resin was coated on hydrated MAPE, in which the anhydride group of MAPE was converted into carboxylic acid group by the reaction with water, the esterification reaction was much faster than that of pristine MAPE, and consequently, the bond strength of the adhesive was much higher than that of pristine MAPE coated with epoxy resin. © 2009 Wiley Periodicals, Inc. J Appl Polym Sci, 2010
Effect of graft‐copolymerization with poly(acrylamide) on rheological and thermal properties of cassava starch
Authors: Jyothi Alummoottil N , Sajeev Moothandasery S , Moorthy Subramoney N , Sreekumar Janardhanan
Published: December 2009

Graft copolymers of different grafting levels were synthesised by the free radical initiated reaction of cassava starch with acrylamide in presence of ceric ammonium nitrate. The viscosity properties of the native granular starch and the grafted starches were determined using a Rapid visco analyzer (RVA) and rheological properties by frequency sweep test under different conditions using a rheometer. Some of the grafted starches exhibited significantly higher and some others exhibited drastically reduced peak viscosity values irrespective of the percentage grafting. All the grafted starches exhibited very good viscosity stability as evidenced from the highly reduced breakdown and higher final viscosity values in comparison to native cassava starch. Thermal analysis of the pure granular cassava starch and grafted starches was carried out using a differential scanning calorimetry (DSC) and thermogravimetry. DSC studies showed that in comparison to native starch, the grafted starches showed lower temperatures of transition. The thermal stability of cassava starch was enhanced by grafting as observed from the thermogravimetric data. © 2009 Wiley Periodicals, Inc. J Appl Polym Sci, 2010
Effect of exposure to 50 Hz magnetic field with or without insulin on blood–brain barrier permeability in streptozotocin‐induced diabetic rats
Authors: Gulturk Sefa , Demirkazik Ayse , Kosar Ilkay , Cetin Ali , Dökmetas Hatice S. , Demir Tuncer
Published: December 2009

We investigated the effect of long‐term exposure to modulation magnetic field (MF), insulin, and their combination on blood–brain barrier (BBB) permeability in a diabetic rat model. Fifty‐three rats were randomly assigned to one of six groups: sham, exposed to no MF; MF, exposed to MF; diabetes mellitus (DM), DM induced with streptozotocin (STZ); DM plus MF (DMMF); DM plus insulin therapy (DMI); and DM plus insulin therapy plus MF (DMIMF). All the rats underwent Evans blue (EB) measurement to evaluate the BBB 30 days after the beginning of experiments. The rats in MF, DMMF, and DMIMF groups were exposed to MF (B = 5 mT) for 165 min every day for 30 days. Mean arterial blood pressure (MABP), body mass, and serum glucose level of the study rats were recorded. The extravasation of brain EB of the MF, DM, DMMF, DMI, and DMIMF groups was higher than that of the sham group and the extravasation of right hemisphere of the DMIMF group was highest (P < 0.05). The post‐procedure body mass of the sham and MF groups were significantly higher than those of the DM and DMMF groups (P < 0.05). In the DM, DMMF, DMI, and DMIMF groups, the baseline glucose was significantly lower than the post‐procedure glucose (P < 0.05). DM and MF increase BBB permeability; in combination, they cause more increase in BBB permeability, and insulin decreases their effect on BBB. Improved glucose metabolism may prevent body mass loss and the hypoglycemic effect of MF. DM increases MABP but MF causes no additional effect. Bioelectromagnetics 31:262–269, 2010. © 2009 Wiley‐Liss, Inc.
Matlab based simulation toolbox for the study and design of induction motor FOC speed drives
Authors: Costa A. , Vilaragut M. , Travieso‐Torres J. C. , Duarte‐Mermoud M. , Muñoz J. , Yznaga I.
Published: December 2009

A new Matlab/Simulink based simulation toolbox for studying and designing induction motor field oriented control schemes is proposed in this article. It has advantages over other previous works published since it is modular, flexible, interactive, easy to use, and the results are closer to the experimental ones because it takes into account real complex effects, such as: motor core saturation, parameter variations with the speed and temperature, sensor signal digital processing, and inverter real voltage waveforms. These results has been successfully applied in teaching undergraduate and graduate courses at the authors' universities for building, identification and characterization of diverse control schemes, analysis of parameter effects, and design and test of new controllers for field oriented control schemes in induction motors. Beside the theoretical and computational basis of the toolbox, simulation results of an indirect field oriented control current regulated pulse width modulation scheme are presented in the article as example. © 2009 Wiley Periodicals, Inc. Comput Appl Eng Educ 20: 295–312, 2012
A novel approach for void avoidance in wireless sensor networks
Authors: Aissani Mohamed , Mellouk Abdelhamid , Badache Nadjib , Boumaza Mouloud
Published: December 2009

We propose a novel approach to treat the problem of void avoidance in sensor networks. In our approach, the choice of the forwarding region around a discovered void is oriented by the locations of (i) the sender node, (ii) the void center and (iii) the destination node. Three void‐avoidance schemes are described which use the same void‐discovery algorithm. Based on an oriented face routing, the first scheme is used by the boundary nodes to prevent packets from dropping. The second scheme is used by sender nodes located n‐hops away from the void boundary to launch a preventive rerouting. The third scheme tends to protect packets from both the concave zones and the boundaries nodes of voids. Proposed schemes are simple to implement. They save network resources and could be easily associated with existing geographic routing protocols. Simulation results show the efficiency of the proposed approach. Copyright © 2009 John Wiley & Sons, Ltd.
Coexistent atypical polypoid adenomyoma and complex atypical endometrial hyperplasia in the uterus
Authors: Horita Ayako , Kurata Atsushi , Komatsu Kyoko , Yajima Masazumi , Sakamoto Atsuhiko
Published: December 2009

We report a case of atypical polypoid adenomyoma (APA) concomitantly identified with complex atypical endometrial hyperplasia (CAH) in the uterus. Since an initial endometrial smear revealed atypical endometrial cells, a diagnosis of CAH was made. Even though a concomitantly performed uterine cervical smear contained both atypical epithelial and stromal cells, the diagnosis of APA was not initially made because the cytological criteria for APA had not been established. Histologically, we recognized both CAH in the uterine corpus and APA in the lower uterine segment in the hysterectomy material. Retrospectively, the cells in the first cervical smear were interpreted as part of APA because the same types of cells were observed in the intraoperative cytology sample. Although the APA and CAH lesions were interposed by normal endometrium, estrogen was suspected to be the common etiological factor. Reports regarding the cytology of APA are currently scarce. To our knowledge, this is the first report showing cytological presentation of association of APA with CAH in addition to the first cervical smear of APA containing both epithelial and stromal components. Identification of abnormal proliferation of epithelium and stromal cells of smooth muscle origin is useful in the cytological diagnosis of APA. Diagn. Cytopathol. 2010. © 2009 Wiley‐Liss, Inc.
An agonistic mAb directed to the TrkC receptor juxtamembrane region defines a trophic hot spot and interactions with p75 coreceptors
Authors: Guillemard Veronique , Ivanisevic Ljubica , Garcia Alba Galan , Scholten Vicki , Lazo Oscar M. , Bronfman Francisca C. , Saragovi H. Uri
Published: December 2009

The D5 domain of TrkC receptors is a docking site for Neurotrophin‐3 (NT‐3), but other domains may be relevant for function or harmonizing signals with p75NTR coreceptors. We report a monoclonal antibody (mAb) 2B7 targeting the juxtamembrane domain of TrkC. mAb 2B7 binds to murine and human TrkC receptors and is a functional agonist that affords activation of TrkC, AKT, and MAPK. These signals result in cell survival but not in cellular differentiation. Monomeric 2B7 Fabs also affords cell survival. Binding of 2B7 mAb and 2B7 Fabs to TrkC are blocked by NT‐3 in a dose‐dependent manner but not by pro‐NT‐3. Expression of p75NTR coreceptors on the cell surface block the binding and function of mAb 2B7, whereas NT‐3 binding and function are enhanced. mAb 2B7 defines a previously unknown neurotrophin receptor functional hot spot; that exclusively generates survival signals; that can be activated by non‐dimeric ligands; and potentially unmasks a site for p75‐TrkC interactions. © 2009 Wiley Periodicals, Inc. Develop Neurobiol, 2010.
Cover Picture: Eur. J. Immunol. 12/09
Authors: Quaedackers Monique E. , Baan Carla C. , Weimar Willem , Hoogduijn Martin J.
Published: December 2009

This issue's cover image depicts in vitro cell‐contact between adipose‐derived stromal cells (ASC) and PBMC, taken from Quaedackers et al. (pp. 3436–3446). In this article, the authors explore the contact‐dependent effect of mesenchymal stromal cells on immune cells, and demonstrate that ASC exert immunomodulatory effects by inhibiting both CD8+ and CD4+ T cell responses.
A Comparison of (R,R)‐Me‐DUPHOS and (R,R)‐DUPHOS‐iPr Ligands in the Pd0‐Catalysed Asymmetric Allylic Alkylation Reaction: Stereochemical and Kinetic Considerations
Authors: Marinho Vanda Raquel , Ramalho J. P. Prates , Rodrigues Ana I. , Burke Anthony J.
Published: December 2009

A relatively unexploited commercial ligand, (R,R)‐DUPHOS‐iPr (1b) was tested in the Pd0‐catalysed asymmetric allylic alkyation reaction using rac‐1,3‐diphenylpropenyl acetate as substrate, malonate as nucleophile and a variety of Pd pre‐catalysts under standard conditions. Excellent ee values (up to ≥ 98 %) could be obtained with 1b, but the conversions were generally inferior to those obtained using (R,R)‐Me‐DUPHOS (1a) under similar conditions. It was also observed that there was a switch in the absolute configuration of the malonate product to (R) on using 1b to form the catalyst. This was an indication of the complementary nature of these two ligands. In order to explain this, a rigorous detailed semi‐emperical computational study was undertaken. DFT calculations of the Fukui Function (FF) were also conducted to confirm the most likely site (electrophilic) for nucleophilic attack on the active Pd‐allyl complex. In the case of the Pd catalyst formed with 1b. This result indicated that stereochemical factors were more important than electronic factors in this reaction with 1b. Kinetic studies were also conducted to compare the activities of the catalysts 2a and 2b formed with (R,R)‐Me‐DUPHOS (1a) and (R,R)‐DUPHOS‐iPr (1b).(© Wiley‐VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2009)
Synthesis and Photophysical Studies of New Fluorescent Indole Derivatives Obtained from β‐Bromodehydroamino Acids – Interaction with Fluoride Anions
Authors: Pereira Goreti , Castanheira Elisabete M. S. , Ferreira Paula M. T. , Queiroz Maria‐João R. P.
Published: December 2009

Several new indole derivatives were synthesised from β‐brominated dehydroamino acids and arylboronic acids by using a strategy developed in our research group that involves a sequential Suzuki–Miyaura cross‐coupling reaction and a metal‐assisted C–N intramolecular cyclisation. The cyclised products were obtained either by direct cyclisation or by isomerisation followed by cyclisation. The photophysical properties of these compounds were studied in four solvents of different polarity (cyclohexane, diethyl ether, acetonitrile and ethanol). All these compounds have reasonably high fluorescence quantum yields (between 16 and 85 %) and show different solvent sensitivity in their fluorescence emission. These results indicate that the indole derivatives prepared are good candidates for fluorescent probes. The response of the new synthesised compounds towards fluoride ion (F–) was evaluated. It was found that methyl 3‐methyl‐1H‐dibenzo[e,g]indole‐2‐carboxylate, methyl 3‐(phenanthren‐9‐yl)‐1H‐dibenzo[e,g]indole‐2‐carboxylate and methyl 1‐(naphthalen‐1‐yl)‐3H‐benzo[e]indole‐2‐carboxylate showed significant spectral changes in fluorescence emission upon F– addition with a decrease in intensity and the appearance of a new band at longer wavelengths. No detectable emission spectral changes were observed when several other anions were added to these compounds, which indicates their selectivity towards F–.
Synthesis of Optically Active Heterocyclic Compounds by Preparation of 1,3‐Dinitro Derivatives and Enzymatic Enantioselective Desymmetrization of Prochiral Diamines
Authors: Ríos‐Lombardía Nicolás , Busto Eduardo , Gotor‐Fernández Vicente , Gotor Vicente
Published: December 2009

A general approach for the highly efficient chemical preparation of novel optically active 2‐substituted propane‐1,3‐diamines is described. Diamines have been obtained from the corresponding commercially available aldehydes in a straightforward two‐step synthesis via the corresponding 1,3‐dinitro compounds, which were hydrogenated under mild reaction conditions by using platinum dioxide as the catalyst. Subsequent enzymatic enantioselective desymmetrization mediated by Pseudomonas cepacia lipase allowed the recovery of a family of monocarbamates in good to high enantiomeric excesses (70–90 % ee).
Synthesis of meso‐Substituted ABCD‐Type Porphyrins by Functionalization Reactions
Authors: Senge Mathias O. , Shaker Yasser M. , Pintea Monica , Ryppa Claudia , Hatscher Sabine S. , Ryan Aoife , Sergeeva Yulia
Published: December 2009

Considerable progress has been made in recent years in the search for synthetic methods leading to functionalized porphyrins, especially for modification of either the β‐ or meso positions. For the latter, total synthesis based on condensation methods or partial synthesis through functionalization of preformed porphyrin have emerged as possible methods. The increasing number of possible technical and medicinal applications for unsymmetrically meso‐substituted porphyrins requires straightforward methods for the preparation of the so‐called ABCD‐porphyrins, i.e., porphyrins with up to four different meso substituents. Here, we describe new strategies for the synthesis of ABCD‐type porphyrins based on porphyrin reactions with organolithium reagents and the use of Pd‐catalyzed coupling reactions. With the whole repertoire of contemporary functionalization methods, a comprehensive analysis and comparison of the various strategies for A‐, AB‐, A2B‐, ABC‐, A2BC‐ and ABCD‐type porphyrins is given. In addition, we report on the synthesis of new functionalized derivatives for some of these porphyrin classes. In practical terms and taking an applied‐science‐oriented approach, the synthesis of unsymmetrically meso‐substituted porphyrins is best accomplished by a combination of well‐developed condensation methods with subsequent functionalization by organolithium compounds or transition‐metal‐catalyzed coupling protocols. The methods described are suitable for the preparation of porphyrins for many divergent applications ranging over amphiphilic porphyrins for photodynamic therapy, push‐pull systems for optical applications and chiral systems useful in catalysis to donor–acceptor systems suitable for electron‐transfer studies.
Antigenotoxic potential of Gymnema montanum leaves on DNA damage in human peripheral blood lymphocytes and HL‐60 cell line
Authors: Ramkumar K.M. , Sankar L. , Manjula C. , Krishnamurthi K. , Devi S. Saravana , Chakrabarti T. , Kalaiselvi K. , Palanivel M. , Rajaguru P.
Published: December 2009

In this study we have evaluated the genoprotective effect of the ethanol extract of Gymnema montanum (GLEt) leaves in human peripheral blood lymphocytes and HL‐60 cell line in vitro using the comet assay. DNA damage was induced by treating the cells with H2O2 and methyl methane sulphonate (MMS). GLEt treatment effectively protected the lymphocytes and HL‐60 cell line from H2O2‐induced oxidative DNA damage in a dose‐dependent manner whereas it was not effective against alkylative DNA damage caused by MMS. The global percent repair efficiency also showed that both pre‐ and post‐ GLEt treatment provided effective protection against H2O2 induced DNA damage but not as effective against MMS. At 200 μg ml−1 level, its repair capacity against H2O2 induced DNA damage was comparable to that of vitamin‐C (100 μM). Furthermore, exposure to GLEt reduced the formation of apoptotic cells caused by H2O2, which was demonstrated by the decreased sub‐G1‐DNA content in cell cycle analysis and apoptotic frequencies of lymphocytes in an annexin‐V binding assay. In addition, GLEt was found to have effective peroxide scavenging ability in dose‐dependent manner. The protective efficiency of the extract was found to be directly proportional to its total phenolic content. The present study indicates that G. montanum leaves are a significant source of phytochemicals with antigenotoxic and antioxidant activity, and thus has potential therapeutic use. Environ. Mol. Mutagen., 2010. © 2009 Wiley‐Liss, Inc.
Recurrent t(2;2) and t(2;8) translocations in rhabdomyosarcoma without the canonical PAX‐FOXO1 fuse PAX3 to members of the nuclear receptor transcriptional coactivator family
Authors: Sumegi Janos , Streblow Renae , Frayer Robert W. , Cin Paola Dal , Rosenberg Andrew , Meloni‐Ehrig Aurelia , Bridge Julia A.
Published: December 2009

The fusion oncoproteins PAX3‐FOXO1 [t(2;13)(q35;q14)] and PAX7‐FOXO1 [t(1;13)(p36;q14)] typify alveolar rhabdomyosarcoma (ARMS); however, 20–30% of cases lack these specific translocations. In this study, cytogenetic and/or molecular characterization to include FISH, reverse transcription polymerase chain reaction (RT‐PCR), and sequencing analyses of five rhabdomyosarcomas [four ARMS and one embryonal rhabdomyosarcoma (ERMS)] with novel, recurrent t(2;2)(p23;q35) or t(2;8)(q35;q13) revealed that these noncanonical translocations fuse PAX3 to NCOA1 or NCOA2, respectively. The PAX3‐NCOA1 and PAX3‐NCOA2 transcripts encode chimeric proteins composed of the paired‐box and homeodomain DNA‐binding domains of PAX3, and the CID domain, the Q‐rich region, and the activation domain 2 (AD2) domain of NCOA1 or NCOA2. To investigate the biological function of these recurrent variant translocations, the coding regions of PAX3‐NCOA1 and PAX3‐NCOA2 cDNA constructs were introduced into expression vectors with tetracycline‐regulated expression. Both fusion proteins showed transforming activity in the soft‐agar assay. Deletion of the AD2 portion of the PAX3‐NCOA fusion proteins reduced the transforming activity of each chimeric protein. Similarly, but with greater impact, CID domain deletion fully abrogated the transforming activity of the chimeric protein. These studies (1) expand our knowledge of PAX3 variant translocations in RMS with identification of a novel PAX3‐NCOA2 fusion, (2) show that both PAX3‐NCOA1 and PAX3‐NCOA2 represent recurrent RMS rearrangements, (3) confirm the transforming activity of both translocation events and demonstrate the essentiality of intact AD2 and CID domains for optimal transforming activity, and (4) provide alternative approaches (FISH and RT‐PCR) for detecting PAX‐NCOA fusions in nondividing cells of RMS. The latter could potentially be used as aids in diagnostically challenging cases. © 2009 Wiley‐Liss, Inc.
Complications and functional outcomes following complex oropharyngeal reconstruction
Authors: Zafereo Mark E. , Weber Randal S. , Lewin Jan S. , Roberts Diana B. , Hanasono Matthew M.
Published: December 2009

Background.

We sought to evaluate postoperative complications and functional outcomes in patients who underwent oropharyngeal reconstruction after oncologic resection.

Methods.

The evaluation constituted a retrospective review of 65 patients who underwent microvascular free flap (85%) and/or pectoralis pedicled flap (18%) oropharyngeal reconstruction after composite resection for advanced oropharyngeal squamous cell carcinoma.

Results.

Perioperative mortality was 1.5%. Overall, 29 patients (45%) experienced surgical or medical complications; however, only 2 patients (3%) required operative intervention. The flap success rate was 100%. Eighty‐six percent of patients were decannulated, 34% were able to meet all of their nutritional needs orally, and 69% attained >80% speech intelligibility. Preoperative swallowing impairment was associated with postoperative feeding tube dependence (p = .006).

Conclusions.

Microvascular free flap and/or pectoralis pedicled flap reconstruction of extensive oropharyngeal defects is safe and reliable, even with advanced disease. Although most patients achieved decannulation and functional speech, almost two thirds remained at least partially feeding tube dependent. © 2009 Wiley Periodicals, Inc. Head Neck, 2010
Glutathione S‐transferase P1 and alpha gene variants; role in susceptibility and tumor size development of oral cancer
Authors: Chen Mu‐Kuan , Tsai Hsiu‐Ting , Chung Tsung‐Te , Su Shih‐Chi , Kao Te‐Yu , Tseng Hsien‐Chun , Liu Te‐Hsiung , Chiou Hui‐Ling , Yang Shun‐Fa
Published: December 2009

Background.

The aim of this study was to estimate the relationship of glutathione S‐transferases (GST)P1, GSTA1, GSTM1, and GSTT1 gene polymorphisms to oral cancer risk.

Methods.

Polymerase chain reaction–restriction fragment length polymorphism (PCR‐RFLP) was used to measure these 4 gene polymorphisms in 274 controls and 164 oral cancer patients.

Results.

Individuals with at least 1 varied G allele of GSTP1 had a 1.53‐fold risk (95% confidence interval [CI] = 1.01–2.31) of developing oral cancer compared with patients with wild‐type A/A homozygotes. Oral cancer patients with at least 1 varied T allele of GSTA1 gene had a 0.42‐fold risk (95% CI = 0.18–0.95) of having a tumor size >2 cm compared with patients with C/C homozygotes.

Conclusions.

The varied G allele of GSTP1 may be considered as a factor contributing to increased susceptibility, whereas the T allele of GSTA1 could be a protective factor for tumor size progression in Taiwanese with oral cancer. © 2009 Wiley Periodicals, Inc. Head Neck, 2010
Preoperative predictors of sternotomy need in mediastinal goiter management
Authors: Casella Claudio , Pata Giacomo , Cappelli Carlo , Salerni Bruno
Published: December 2009

Background.

The objective of this study was to identify the preoperative risk factors for patients in need of a sternotomy in the management of mediastinal goiters in order to provide better preoperative planning and patient consent.

Methods.

We analyzed 98 patients who underwent surgery for mediastinal goiters (goiters extending below the thoracic inlet ≥3 cm with the neck in hyperextension) between 1995 and 2008. Twelve (12.2%) of the patients required a sternotomy. The patients' features were analyzed by the surgical approach performed. Logistic regression analysis was used to study which variables were influencing the surgical strategy. The receiver operating characteristic (ROC) curves were designed when appropriate.

Results.

The analysis disclosed the following risk factors: radiologic extension of mediastinal goiters below the aortic arch (odds ratio [OR] = 32.87; 95% confidence interval [CI] = 4.04–267.12; p < .0001); posterior mediastinum involvement for mediastinal goiters with subaortic extension (OR = 7.2; 95% CI = 1.52–34.14; p = .0244); history of mediastinal goiters before surgery (for mediastinal goiters aged >160 months: OR = 22.8; 95% CI = 5.28–98.53; p < .0001).

Conclusions.

Sternotomy need for mediastinal goiter removal can be predicted; in such cases surgeons should not hesitate to perform it for minimizing complications. © 2009 Wiley Periodicals, Inc. Head Neck, 2010
Who is citing whom: Citation network analysis among HRD publications from 1990 to 2007
Authors: Jo Sung Jun , Jeung Chang‐Wook , Park Sunyoung , Yoon Hea Jun
Published: December 2009

A citation network analysis among four journals in human resource development (HRD) was conducted to discover the major themes of published articles in HRD. A total of 1,410 articles from 1990 to 2007 were coded. Main path analysis, influence analysis, and reduced network analysis were conducted for citation network analysis. The key findings are

The HRD citation network is characterized as high cohesiveness locally and low separation globally.

HRD texts tend to gather around texts dealing with three significant topics.

A reduced citation network generated based on cliques is divided into four blocks.

A geographical position of a text in the citation network is highly associated with the topics (theory building or training transfer) and with the nature of the study (foundational or applied).

Implications of the current study and suggestions for future study based on the limitations of the study are addressed.
Career decision‐making self‐efficacy, integration, and the likelihood of managerial retention in governmental agencies
Authors: Peterson Shari
Published: December 2009

Results based on responses from 679 managers in three governmental agencies confirmed that career‐related organizational practices and relationships impacted their staying in the organization. Specifically, managers who scored higher in career decision‐making self‐efficacy, a relatively new variable to the turnover literature, career integration, and work‐life balance were 63‐69° more likely to stay. HRD has an opportunity to identify organizational work environments that lead to a greater sense of managerial employee connectedness (integration) with the organization. As well, HRD could strategically reduce costs associated with turnover by leading initiatives to design and develop or enhance career development programs. If managers have greater opportunities to identify career paths and achieve their career goals within their current organizations, they may be less likely to seek those opportunities elsewhere.
Signal generation and Raman‐resonant imaging by non‐degenerate four‐wave mixing under tight focusing conditions
Authors: Weeks Tyler , Schie Iwan W. , Wachsmann‐Hogiu Sebastian , Huser Thomas
Published: December 2009

The authors demonstrate Raman‐resonant imaging based on the simultaneous generation of several nonlinear frequency mixing processes resulting from a 3‐color coherent anti‐Stokes Raman scattering (CARS) experiment. The interaction of three coincident short‐pulsed laser beams simultaneously generates both 2‐color (degenerate) CARS and 3‐color (non‐degenerate) CARS signals, which are collected and characterized spectroscopically – allowing for resonant, doubly‐resonant, and non‐resonant contrast mechanisms. Images obtained from both 2‐color and 3‐color CARS signals are compared and found to provide complementary information. The 3‐color CARS microscopy scheme provides a versatile multiplexed modality for biological imaging, which may extend the capabilities of label‐free non‐linear microscopy, e.g. by probing multiple Raman resonances. (© 2010 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Improvements in the production of bacterial synthesized biocellulose nanofibres using different culture methods
Authors: Sani Amir , Dahman Yaser
Published: December 2009

This review summarizes previous work that was done to improve the production of bacterial cellulose nanofibres. Production of biocellulose nanofibres is a subject of interest owing to the wide range of unique properties that makes this product an attractive material for many applications. Bacterial cellulose is a natural nanomaterial that has a native dimension of less than 50 nm in diameter. It is produced in the form of nanofibres, yielding a very pure cellulose product with unique physical properties that distinguish it from plant‐derived cellulose. Its high surface‐to‐volume ratio combined with its unique properties such as poly‐functionality, hydrophilicity and biocompatibility makes it a potential material for applications in the biomedical field. The purpose of this review is to summarize the methods that might help in delivering microbial cellulose to the market at a competitive cost. Different feedstocks in addition to different bioreactor systems that have been previously used are reviewed. The main challenge that exists is the low yield of the cellulosic nanofibres, which can be produced in static and agitated cultures. The static culture method has been used for many years. However, the production cost of this nanomaterial in bioreactor systems is less expensive than the static culture method. Biosynthesis in bioreactors will also be less labour intensive when scaled up. This would improve developing intermediate fermentation scale‐up so that the conversion to an efficient large‐scale fermentation technology will be an easy task. Copyright © 2009 Society of Chemical Industry
Control of the Fenton process for textile wastewater treatment using artificial neural networks
Authors: Yu Ruey‐Fang , Chen Ho‐Wen , Liu Kuang‐Yu , Cheng Wen‐Po , Hsieh Peng‐Han
Published: December 2009

BACKGROUND: The Fenton process is a popular advanced oxidation process (AOP) for treating textile wastewater. However, high consumption of chemical reagents and high production of sludge are typical problems when using this process and in addition, textile wastewater has wide‐ranging characteristics. Therefore, dynamically regulating the Fenton process is critical to reducing operation costs and enhancing process performance. The artificial neural network (ANN) model has been adopted extensively to optimize wastewater treatment. This study presents a novel Fenton process control strategy using ANN models and oxygen reduction potential (ORP) monitoring to treat two synthetic textile wastewaters containing two common dyes.

RESULTS: Experimental results indicated that the ANN models can predict precisely the colour and chemical oxygen demand (COD) removal efficiencies for synthetic textile wastewaters with correlation coefficients (R2) of 0.91–0.99. The proposed control strategy based on these ANN models effectively controls the Fenton process for various effluent colour targets. For treating the RB49 synthetic wastewater to meet the effluent colour targets of 550 and 1500 ADMI units, the required Fe+2 doses were 13.0–84.3 and 5.5–34.6 mg L−1 (Fe+2/H2O2 = 3.0), resulting in average effluent colour values of 520 and 1494 units. On the other hand, an effluent colour target of 550 ADMI units was achieved for RBB synthetic wastewater. The required Fe+2 doses were 14.6–128.0 mg L−1; the average effluent colour values were 520 units.

CONCLUSION: The Fenton process for textile wastewater treatment was effectively controlled using a control strategy applying the ANN models and ORP monitoring, giving the benefit of chemical cost savings. Copyright © 2009 Society of Chemical Industry
Effect of perchloroethylene (PCE) and hydraulic shock loads on a membrane‐aerated biofilm reactor (MABR) biodegrading PCE
Authors: Ohandja Dieudonné‐Guy , Stuckey David C.
Published: December 2009

BACKGROUND: A membrane‐aerated biofilm reactor (MABR) has previously been used to provide both anaerobic and aerobic conditions for mineralisation of perchloroethylene (PCE). However, very little is known about the stability of this reactor under hydraulic and PCE shock loads. An MABR was therefore subjected to sudden hydraulic and PCE shock loads in order to investigate its stability under such conditions.

RESULTS: After each shock, the reactor responded with an increase of chemical oxygen demand (COD) and volatile fatty acids (VFA)s, a breakthrough of PCE and its biodegradation intermediates in the effluent, and a decrease in methane production. Although some PCE biodegradation intermediates were found in the effluent during each shock loading, the MABR performance recovered without the accumulation of any particular PCE biodegradation intermediates during PCE shock loads. During the hydraulic shock loads, the MABR was unstable at hydraulic retention times (HRTs) of 6 h with PCE and its biodegradation intermediates detected in the effluent. However, these intermediates were degraded when the HRT was reset to 48 h.

CONCLUSIONS: This study suggests that MABRs can withstand fluctuations in influent strength and flows which occur in wastewater treatment works. Copyright © 2009 Society of Chemical Industry
A single pretreatment by zoledronic acid converts metastases from osteolytic to osteoblastic in the rat
Authors: Nyangoga Hervé , Blouin Stéphane , Libouban Hélène , Baslé Michel Félix , Chappard Daniel
Published: December 2009

Bone metastases are severe complications of cancers associated with increased morbidity, pain, risk fracture, and reduced life span for patients. Bisphosphonates emerged as a relief treatment in bone metastases. A single dose of zoledronic acid (78 μg/kg) was injected into six Copenhagen rats 4 days before receiving an intraosseous inoculation of metastatic anaplastic tumor of lymph node and lung cell (MLL) prostate cancer cells. Rat femurs were analyzed for changes by microCT and histomorphometry; trabecular volume, trabecular characteristics, osteoid parameters, osteoblastic surfaces, and osteoclast number were measured. Values were compared to a group of SHAM animals, a group of SHAM animals having received zoledronic acid and animals inoculated with MLL cells. All rats were euthanized after 1 month. MLL cells induced osteolysis in the metaphysis with extension of the tumor to soft tissues through cortical perforations. Zoledronic acid induced a marked osteosclerosis in the primary spongiosa in both SHAM and rats inoculated with MLL. Osteosclerosis was obtained in the secondary spongiosa of MLL rats. The bisphosphonate preserved cortical integrity in all animals, and no extension to soft tissues was observed in most animals. The number of osteoclasts was elevated, indicating that there was no apoptosis of osteoclasts but they became inactive. Osteosclerosis was associated with increased osteoblastic surfaces. A single zoledronic acid injection turned osteolytic metastases into osteosclerotic and preserved cortical integrity. Microsc. Res. Tech. 73:733–740, 2010. © 2009 Wiley‐Liss, Inc.
Morphology Development and Interfacial Interactions in Polycaprolactone/Thermoplastic‐Starch Blends
Authors: Li Gang , Favis Basil D.
Published: December 2009

The coalescence, continuity development, dynamic and static mechanical properties and interfacial interactions are studied for polycaprolactone/thermoplastic starch blends. These blends, prepared by a one‐step extrusion process, demonstrate the features of a highly interacting system and the tensile mechanical properties demonstrate exceptional ductility at very high levels of thermoplastic starch without any added interfacial modifier. Virtually all the results can be explained by two phenomena: a high elasticity of the thermoplastic starch phase and a strong compatibility between TPS and PCL due to hydrogen bonding. The high level of compatibility is facilitated by the high mobility of the TPS chains due to the high plasticizer content and a highly effective TPS plasticization protocol.

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Stimulated Deformation of Polysiloxane Capsules in External Electric Fields
Authors: Degen Patrick , Chen Zhao , Rehage Heinz
Published: December 2009

Due to their pronounced viscoelastic properties polymer microcapsules are able to undergo mechanical deformations when they are stimulated by external signals. The aim of our work was to prepare new types of electric switchable microcapsules based on the interfacial polycondensation of octadecyltrichlorosilane (OTS) and to investigate their deformation behavior in externally electric fields. In a series of experiments we explored the influence of different additives on the deformation behavior of the capsules in electric fields as well as on the shear rheological properties of the polysiloxane networks at the planar interface. We could show that the additives had a significant influence on the rheological membrane properties, but we observed only small changes in the deformation of the whole capsules.

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1,1‐Diphenyl Ethylene‐Mediated Radical Polymerisation: A General Non‐Metal‐Based Technique For The Synthesis Of Precise Core Cross‐Linked Star Polymers
Authors: Tan Jing Fung , Blencowe Anton , Goh Tor Kit , Qiao Greg G.
Published: December 2009

This communication details the successful synthesis of low polydispersity core cross‐linked star (CCS) polymers via DPE‐mediated polymerisation. We demonstrate the ability to produce poly(methyl methacrylate) and poly(acrylonitrile) CCS polymers that are currently inaccessible via the two most common non‐metal‐based controlled radical polymerisation techniques (NMP and RAFT polymerisations).

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Expression and chromosomal organization of mouse meiotic genes
Authors: Ben‐Asher Hiba Waldman , Shahar Iris , Yitzchak Assaf , Mehr Ramit , Don Jeremy
Published: December 2009

Microarray technology which enables large scale analysis of gene expression and thus comparison between transcriptomes of different cell types, cells undergoing different treatments or cells at different developmental stages has also been used to study the transcriptome involved with spermatogenesis. Many new germ cell‐specific genes were determined, and the resulting genes were classified according to different criteria. However, the biological significance of these classifications and their clustering according to developmental transcriptional patterns during spermatogenesis have not yet been addressed. In this study we utilized mouse testicular transcriptome analysis at five distinct post‐natal ages (Days 7, 10, 12, 14, and 17), representing distinct meiotic stages, in an attempt to better understand the biological significance of genes clustered into similar expression patterns during this process. Among 790 sequences that showed an expression level change of twofold or more in any of the five key stages that were monitored, relative to the geometric average of all stages, about 40% peaked and about 30% were specifically suppressed at post‐natal day 14 (representing the early pachytene stage of spermatocytes), reflecting tight transcriptional regulation at this stage. We also found that each of the six main transcription clusters that were determined was characterized by statistically significant representation of genes related to specific biological processes. Finally, our results indicated that genes important for meiosis are not randomly distributed along the mouse genome but rather preferentially located on specific chromosomes, suggesting for the first time that chromosomal location might be a regulating factor of meiotic gene expression. Mol. Reprod. Dev. 77: 241–248, 2010. © 2009 Wiley‐Liss, Inc.
Arterial transit time effects in pulsed arterial spin labeling CBF mapping: Insight from a PET and MR study in normal human subjects
Authors: Qiu Maolin , Paul Maguire R. , Arora Jagriti , Planeta‐Wilson Beata , Weinzimmer David , Wang Jinghua , Wang Yuenan , Kim Hyeonjin , Rajeevan Nallakkandi , Huang Yiyun , Carson Richard E. , Constable R. Todd
Published: December 2009

Arterial transit time (ATT), a key parameter required to calculate absolute cerebral blood flow in arterial spin labeling (ASL), is subject to much uncertainty. In this study, ASL ATTs were estimated on a per‐voxel basis using data measured by both ASL and positron emission tomography in the same subjects. The mean ATT increased by 260 ± 20 (standard error of the mean) ms when the imaging slab shifted downwards by 54 mm, and increased from 630 ± 30 to 1220 ± 30 ms for the first slice, with an increase of 610 ± 20 ms over a four‐slice slab when the gap between the imaging and labeling slab increased from 20 to 74 mm. When the per‐slice ATTs were employed in ASL cerebral blood flow quantification and the in‐slice ATT variations ignored, regional cerebral blood flow could be significantly different from the positron emission tomography measures. ATT also decreased with focal activation by the same amount for both visual and motor tasks (∼80 ms). These results provide a quantitative relationship between ATT and the ASL imaging geometry and yield an assessment of the assumptions commonly used in ASL imaging. These findings should be considered in the interpretation of, and comparisons between, different ASL‐based cerebral blood flow studies. The results also provide spatially specific ATT data that may aid in optimizing the ASL imaging parameters. Magn Reson Med, 2010. © 2009 Wiley‐Liss, Inc.
Functional copolymer/organo‐MMT nanoarchitectures. III. Dynamic mechanical behavior of poly(IA‐co‐BMA)‐organo‐MMT clay nanocomposites
Authors: Rzayev Zakir M. O. , Güner Ali , Söylemez Ernur A. , Kavlak Serap
Published: December 2009

Functional copolymer/organo‐silicate [N,N′‐dimethyldodecyl ammonium cation surface modified montmorillonite (MMT)] layered nanocomposites have been synthesized by interlamellar complex‐radical copolymerization of pre‐intercalated itaconic acid (IA)/organo‐MMT complex as a “nanoreactor” with n‐butyl methacrylate (BMA) as an internal plasticization comonomer in the presence of radical initiator. Comparative analysis of physical structure, dynamic mechanical analysis parameters, and surface morphology of the obtained copolymers and their nanocomposites indicated that the interlayer H‐bonding and flexible n‐butyl ester linkages take place an important role in interlamellar copolymerization and intercalation/exfoliation of copolymer chains. It was found that nanocomposites' dynamic mechanical properties strongly depended on the force of interfacial H‐bonding and amount of BMA units. An increase in both of these parameters leads to enhanced intercalation and exfoliation in situ processes of copolymer chains and the formation of hybrid nanocomposites. Copyright © 2009 John Wiley & Sons, Ltd.
Synthesis and thermal properties of ester‐type crosslinked epoxy resins derived from lignosulfonate and glycerol
Authors: Ismail Tuan Noor Maznee Tuan , Hassan Hazimah Abu , Hirose Shigeo , Taguchi Yoichi , Hatakeyama Tatsuko , Hatakeyama Hyoe
Published: December 2009

Among various biomass‐based components, both lignin and glycerol are important, since they are abundantly produced as by‐products in industrial processes. Accordingly, in the present study, new types of crosslinked epoxy resins were synthesized from lignin and glycerol. Polymers derived from two types of lignin‐based crosslinked epoxy resins were prepared through two‐step reactions, ester‐carboxylic acid derivative preparation followed by crosslinked epoxy resin preparation, in order to establish a crosslinked epoxy resin system in which glycerol units were included. The resins obtained were labeled as follows: series 1, lignosulfonate‐glycerol polyacid (Ser1LSGLYPA); and series 2, glycerol diglycidyl ether (Ser2GLYDGE). The functional groups of the resins were analyzed using Fourier transform infrared spectrometry. The thermal properties of the resins were analyzed using differential scanning calorimetry and thermogravimetry. The glass transition temperature of the crosslinked epoxy resins increased with increasing LSGLYPA and GLYDGE contents for Ser1LSGLYPA and Ser2GLYDGE, respectively. The thermal degradation temperature for Ser1LSGLYPA and Ser2GLYDGE did not show significant change, suggesting that the crosslinked epoxy resins were thermally stable. The mass residue at 500 °C was not affected by the changes of LSGLYPA and GLYDGE contents. Copyright © 2009 Society of Chemical Industry
A study of the flame‐retardant properties of polypropylene/Al(OH)3/Mg(OH)2 composites
Authors: Liang Jizhao , Zhang Yingjie
Published: December 2009

Polymeric materials are used extensively, but their applications are limited because many of them are flammable. Therefore ways to make them flame retardant have received much attention. In this work, polypropylene (PP) was used as the matrix resin, aluminium hydroxide (Al(OH)3) and magnesium hydroxide (Mg(OH)2) as flame‐retardant additives and zinc borate (ZB) as a flame‐retardant synergist. PP/Al(OH)3/Mg(OH)2 and PP/Al(OH)3/Mg(OH)2/ZB flame‐retardant composites were prepared with a twin‐screw extruder. The flame‐retardant properties, i.e. oxygen index (OI), burning velocity and smoke density, of the composites were measured. The results showed that OI increased with an increase of the filler content and decreased with an increase of the filler particle diameter. The burning velocity decreased with an increase of the filler content, while it first increased and then decreased with an increase of the filler particle diameter. The smoke density decreased with an increase of the filler content and increased with an increase of the filler particle diameter. There was a flame‐retardant synergy between Al(OH)3/Mg(OH)2 and ZB in the composites, and the smoke suppression effect was marked when ZB was added. Copyright © 2009 Society of Chemical Industry