bluuebunny/crossref_metadata_2025 huggingface dataset:
Design and Synthesis of Blue‐Emitting Cyclometalated Iridium(III) Complexes Based on Regioselective Functionalization
Authors: Hisamatsu Yosuke , Aoki Shin
Published: October 2011

A series of tris‐cyclometalated IrIII complexes were prepared by regioselective substitution reactions (formylation, thiocyanation, and iodination) and subsequent conversions (cyanation, cross‐coupling reaction, reduction, and oxidation) on a 2‐(4′‐methoxyphenyl)pyridine (mppy) ligand of fac‐[Ir(mppy)3]. The introduction of electron‐withdrawing groups such as CHO, CN, and sulfonyl groups (SO2Me, SO2Ar) at the 5′‐position of the phenyl ring of the mppy portion induces a considerable blueshift in luminescence emission (from 495 nm to approximately 465 nm) in degassed organic solvents.
Synthesis and Characterization of Dioxidodiphenylrhenium(VII) Propionate
Authors: Huber Stefan , Cokoja Mirza , Drees Markus , Herrmann Wolfgang A. , Kühn Fritz E.
Published: October 2011

Treatment of propylperrhenate with 1 equiv. phenylzinc acetate yields dioxidodiphenylrhenium propionate. This novel complex can be synthesized with a yield of 41 % and is characterized by NMR and IR spectroscopy, as well as single‐crystal X‐ray diffraction. The compound is sensitive to moisture. It decomposes in sunlight and above 0 °C. The crystal structure has distorted octahedral symmetry around the rhenium center. Both rhenium–carbon bonds have a length of 2.141 Å and are significantly longer than other comparable rhenium–carbon bonds.
On‐chip integrated labelling, transport and detection of tumour cells
Authors: Woods Jane , Docker Peter T. , Dyer Charlotte E. , Haswell Stephen J. , Greenman John
Published: October 2011

Microflow cytometry represents a promising tool for the investigation of diagnostic and prognostic cellular cancer markers, particularly if integrated within a device that allows primary cells to be freshly isolated from the solid tumour biopsies that more accurately reflect patient‐specific in vivo tissue microenvironments at the time of staining. However, current tissue processing techniques involve several sequential stages with concomitant cell losses, and as such are inappropriate for use with small biopsies. Accordingly, we present a simple method for combined antibody‐labelling and dissociation of heterogeneous cells from a tumour mass, which reduces the number of processing steps. Perfusion of ex vivo tissue at 4°C with antibodies and enzymes slows cellular activity while allowing sufficient time for the diffusion of minimally active enzymes. In situ antibody‐labelled cells are then dissociated at 37°C from the tumour mass, whereupon hydrogel‐filled channels allow the release of relatively low cell numbers (<1000) into a biomimetic microenvironment. This novel approach to sample processing is then further integrated with hydrogel‐based electrokinetic transport of the freshly liberated fluorescent cells for downstream detection. It is anticipated that this integrated microfluidic methodology will have wide‐ranging biomedical and clinical applications.
A sensitive and rapid immunoassay for quantification of testosterone by microchip electrophoresis with enhanced chemiluminescence detection
Authors: Huang Yong , Shi Ming , Zhao Shulin , Liang Hong
Published: October 2011

A sensitive and rapid approach to perform testosterone (T) competitive immunoassay by microchip electrophoresis (MCE) with chemiluminescence (CL) detection was developed. The assay is based on the competitive immunoreactions between T and N‐(4‐aminobutyl)‐N‐ethylisoluminol‐labeled T (ABEI‐T) with a limited amount of antibody (Ab), and the rapid electrophoretic separation of an equilibrated mixture of ABEI‐T‐Ab complex and free ABEI‐T, followed by CL detection using horseradish peroxidase‐catalyzed ABEI‐H2O2 system. Free ABEI‐T and the ABEI‐T‐Ab complex are well separated within 30 s under the assay conditions. The developed method could be used to determine T with good precision and a detection limit lower than 1.0 nM. This method was applied for the quantification of T in human serum. The results demonstrated that the current MCE‐CL‐based competitive immunoassay maybe served as an alternative tool for clinical analysis.
Role of SOCS1 in tumor progression and therapeutic application
Authors: Zhang Jing , Li Hui , Yu Jin‐Pu , Wang Shizhen Emily , Ren Xiu‐Bao
Published: October 2011

SOCS1, a prototype molecule of the SOCS family, was initially defined as a suppressor of cytokine signaling. The molecular mechanisms of SOCS1‐mediated functions have been subsequently identified by studies using gene knockout mice and gene silencing technology. As part of a negative feedback regulation, SOCS1 downregulates cytokine signaling through direct inhibition of the JAK tyrosine kinase and the signaling cascade of activated cytokine receptors, thereby attenuating cytokine‐initiated signal transduction. Moreover, other studies have demonstrated that SOCS1 also downregulates TLR signaling through direct and indirect mechanisms. Both cytokine receptor and TLR signaling pathways mediate important functions in survival, maturation and differentiation of various types of cells and in the regulation of immune function. Abnormal expression of SOCS1 in tumor cells has been detected in various human cancers, where it is associated with dysregulation of cytokine receptor and TLR signaling to promote cell transformation. Recent studies on the function of SOCS1 in tumor cells have revealed its novel role in carcinogenesis. In this review, we will focus on the mechanism of action of SOCS1 in both tumor cells and antigen‐presenting cells in the tumor microenvironment. The potential of using SOCS1 as a diagnostic marker and therapeutic target in tumor diagnosis, prognosis and treatment is discussed.
A mouse model for spondyloepiphyseal dysplasia congenita with secondary osteoarthritis due to a Col2a1 mutation
Authors: Esapa Christopher T , Hough Tertius A , Testori Sarah , Head Rosie A , Crane Elizabeth A , Chan Carol PS , Evans Holly , Bassett JH Duncan , Tylzanowski Przemko , McNally Eugene G , Carr Andrew J , Boyde Alan , Howell Peter GT , Clark Anne , Williams Graham R , Brown Matthew A , Croucher Peter I , Nesbit M Andrew , Brown Steve DM , Cox Roger D , Cheeseman Michael T , Thakker Rajesh V
Published: October 2011

Progeny of mice treated with the mutagen N-ethyl-N-nitrosourea (ENU) revealed a mouse, designated Longpockets (Lpk), with short humeri, abnormal vertebrae, and disorganized growth plates, features consistent with spondyloepiphyseal dysplasia congenita (SEDC). The Lpk phenotype was inherited as an autosomal dominant trait. Lpk/+ mice were viable and fertile and Lpk/Lpk mice died perinatally. Lpk was mapped to chromosome 15 and mutational analysis of likely candidates from the interval revealed a Col2a1 missense Ser1386Pro mutation. Transient transfection of wild-type and Ser1386Pro mutant Col2a1 c-Myc constructs in COS-7 cells and CH8 chondrocytes demonstrated abnormal processing and endoplasmic reticulum retention of the mutant protein. Histology revealed growth plate disorganization in 14-day-old Lpk/+ mice and embryonic cartilage from Lpk/+ and Lpk/Lpk mice had reduced safranin-O and type-II collagen staining in the extracellular matrix. The wild-type and Lpk/+ embryos had vertical columns of proliferating chondrocytes, whereas those in Lpk/Lpk mice were perpendicular to the direction of bone growth. Electron microscopy of cartilage from 18.5 dpc wild-type, Lpk/+, and Lpk/Lpk embryos revealed fewer and less elaborate collagen fibrils in the mutants, with enlarged vacuoles in the endoplasmic reticulum that contained amorphous inclusions. Micro-computed tomography (CT) scans of 12-week-old Lpk/+ mice revealed them to have decreased bone mineral density, and total bone volume, with erosions and osteophytes at the joints. Thus, an ENU mouse model with a Ser1386Pro mutation of the Col2a1 C-propeptide domain that results in abnormal collagen processing and phenotypic features consistent with SEDC and secondary osteoarthritis has been established. © 2012 American Society for Bone and Mineral Research
Cell autonomous requirement of connexin 43 for osteocyte survival: Consequences for endocortical resorption and periosteal bone formation
Authors: Bivi Nicoletta , Condon Keith W , Allen Matthew R , Farlow Nathan , Passeri Giovanni , Brun Lucas R , Rhee Yumie , Bellido Teresita , Plotkin Lilian I
Published: October 2011

Connexin 43 (Cx43) mediates osteocyte communication with other cells and with the extracellular milieu and regulates osteoblastic cell signaling and gene expression. We now report that mice lacking Cx43 in osteoblasts/osteocytes or only in osteocytes (Cx43ΔOt mice) exhibit increased osteocyte apoptosis, endocortical resorption, and periosteal bone formation, resulting in higher marrow cavity and total tissue areas measured at the femoral mid-diaphysis. Blockade of resorption reversed the increased marrow cavity but not total tissue area, demonstrating that endocortical resorption and periosteal apposition are independently regulated. Anatomical mapping of apoptotic osteocytes, osteocytic protein expression, and resorption and formation suggests that Cx43 controls osteoclast and osteoblast activity by regulating osteoprotegerin and sclerostin levels, respectively, in osteocytes located in specific areas of the cortex. Whereas empty lacunae and living osteocytes lacking osteoprotegerin were distributed throughout cortical bone in Cx43ΔOt mice, apoptotic osteocytes were preferentially located in areas containing osteoclasts, suggesting that osteoclast recruitment requires active signaling from dying osteocytes. Furthermore, Cx43 deletion in cultured osteocytic cells resulted in increased apoptosis and decreased osteoprotegerin expression. Thus, Cx43 is essential in a cell-autonomous fashion in vivo and in vitro for osteocyte survival and for controlling the expression of osteocytic genes that affect osteoclast and osteoblast function. © 2012 American Society for Bone and Mineral Research
Developmental integration of feather growth and pigmentation and its implications for the evolution of diet‐derived coloration
Authors: Landeen Elizabeth A. , Badyaev Alexander V.
Published: October 2011

Variation in avian coloration is produced by coordinated pigmentation of thousands of growing feathers that vary in shape and size. Although the functional consequences of avian coloration are frequently studied, little is known about its developmental basis, and, specifically, the rules that link feather growth to pigment uptake and synthesis. Here, we combine biochemical, modeling, and morphometric techniques to examine the developmental basis of feather pigmentation in house finches (Carpodacus mexicanus)—a species with extensive variation in both growth dynamics of ornamental feathers and their carotenoid pigmentation. We found that the rate of carotenoid uptake was constant across a wide range of feather sizes and shapes, and the relative pigmented area of feathers was independent of the total amount of deposited carotenoids. Analysis of the developmental linkage of feather growth and pigment uptake showed that the mechanisms behind partitioning the feather into pigmented and nonpigmented parts and the mechanisms regulating carotenoid uptake into growing feathers are partially independent. Carotenoid uptake strongly covaried with early elements of feather differentiation (the barb addition rate and diameter), whereas the pigmented area was most closely associated with the rate of feather growth. We suggest that strong effects of carotenoid uptake on genetically integrated mechanisms of feather growth and differentiation provide a likely route for genetic assimilation of diet‐dependent coloration. J. Exp. Zool. (Mol. Dev. Evol.) 318:59–70, 2012. © 2011 Wiley Periodicals, Inc.
Catalytic antibodies from HIV‐infected patients specifically hydrolyzing viral integrase suppress the enzyme catalytic activities
Authors: Odintsova Elena S. , Baranova Svetlana V. , Buneva Valentina N. , Calmels Christina , Parissi Vincent , Andreola Marie‐Line , Zakharova Olga D. , Nevinsky Georgy A.
Published: October 2011

Human immunodeficiency virus type 1 integrase (IN) catalyzes integration of a DNA copy of the viral genome into the host genome. It was shown previously that IN preincubation with various oligodeoxynucleotides (ODNs) induces formation of dimers and oligomers of different gyration radii; only specific ODNs stimulate the formation of catalytically active dimers. Here we have shown that preincubation of IN with specific and nonspecific ODNs leads to a significant and comparable decrease in its hydrolysis by chymotrypsin, while nonspecific ODNs protect the enzyme from the hydrolysis by trypsin worse than specific ODNs; all ODNs had little effect on the IN hydrolysis by proteinase K. In contrast to canonical proteweases, IgGs from HIV‐infected patients specifically hydrolyze only IN. While d(pT)n markedly decreased the IgG‐dependent hydrolysis of IN, d(pA)n and d(pA)n•d(pT)n demonstrated no detectable protective effect. The best protection from the hydrolysis by IgGs was observed for specific single‐ and especially double‐stranded ODNs. Although IN was considerably protected by specific ODNs, proteolytic IgGs and IgMs significantly suppressed both 3′‐processing and integration reaction catalyzed by IN. Since anti‐IN IgGs and IgMs can efficiently hydrolyze IN, a positive role of abzymes in counteracting the infection cannot be excluded. Copyright © 2011 John Wiley & Sons, Ltd.
Experimental Validation of Intermediate Termination in RAFT Polymerization with Dithiobenzoate via Comparison of Miniemulsion and Bulk Polymerization Rates
Authors: Suzuki Kiyoshi , Nishimura Yuko , Kanematsu Yuta , Masuda Yoshie , Satoh Shuzaemon , Tobita Hidetaka
Published: October 2011

To understand if either of two controversial models for the retardation by RAFT agents is applicable, styrene polymerization using dithiobenzoate as the RAFT agent is carried out in both bulk and miniemulsion systems with the same rates of radical generation and the same RAFT agent concentrations. Miniemulsion polymerization with average diameters of the miniemulsion droplets of ≈107 nm is by far faster than in bulk, and the obtained rate of polymerization agrees well with the calculated results assuming a bimolecular termination between propagating radical and intermediate radical, generated by the addition reaction of propagating radical to the RAFT agent, which shows that the intermediate termination is the major reason for rate retardation by the RAFT agent.

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α‐Agonisten in der Augenheilkunde
Authors: Anton Alexandra , Jordan Jens
Published: October 2011

α‐Agonisten werden am Auge zur Behandlung des Glaukoms eingesetzt. Sie senken über eine Hemmung der Kammerwasserproduktion und über eine Steigerung des Kammerwasserabflusses den Augeninnendruck. Heutzutage werden aufgrund des geringeren Nebenwirkungsprofils bevorzugt selektive α2‐Agonisten angewandt. Sie gehören aufgrund ihrer lokalen und systemischen Nebenwirkungen jedoch zu den Therapeutika der 2. Wahl. Experimentelle Ergebnisse weisen darauf hin, dass α2‐Agonisten einen additiven neuroprotektiven Effekt haben. In klinischen Studien konnte dies jedoch bisher nicht belegt werden.
Determination of Nucleosides and Nucleobases in the Pollen of Typha Angustifolia by UPLC‐PDA‐MS
Authors: Tao Wei‐Wei , Duan Jin‐Ao , Yang Nian‐Yun , Guo Sheng , Zhu Zhen‐Hua , Tang Yu‐Ping , Qian Da‐Wei
Published: October 2011

Introduction

The pollen of Typha angustifolia L. has been used traditionally for the treatment of dysmenorrhea, stranguria and metrorrhagia in China. Recently, nucleosides and nucleobases have been proven as important bioactive compounds. Exploration of the nucleoside and nucleobase profiles from the pollen of T. angustifolia is important for improving its therapeutic value and could be convenient for its quality evaluation.

Objective

To establish an UPLC‐PDA‐MS method for simultaneous determination of nucleosides and nucleobases in the pollen of T. angustifolia.

Methodology

The analysis was performed on an Acuity UPLCHSS T3 column with a gradient elution of 5 mm ammonium acetate and methanol solution at a flow rate of 0.3 mL/min.

Results

Satisfactory separation of these compounds was obtained in less than 12 min. All calibration curves showed good linear regression (r2 > 0.9995). The method provided good accuracy, precision, recovery, and sensitivity for the quantification of the 10 compounds analysed.

Conclusion

The UPLC method established is very helpful for optimising their content and could be convenient for quality evaluation of the pollen of T. angustifolia, which has not been reported as far as we are aware. Copyright © 2011 John Wiley & Sons, Ltd.
Effect of Se flux on CuIn1‐xGaxSe2 film in reactive sputtering process
Authors: Park Nae‐Man , Lee Ho Sub , Cho Dae‐Hyung , Chung Yong‐Duck , Kim Kyung‐Hyun , Lee Kyu‐Seok , Kim Jeha
Published: October 2011

CuIn1‐xGaxSe2 (CIGS) thin films were grown on Mo/soda lime glass using a reactive sputtering process in which a Se cracker was used to deliver reactive Se molecules. The Cu0·6 Ga0·4 and Cu0·4In0·6 targets were simultaneously sputtered under the delivery of reactive Se. The effects of Se flux on CIGS film deposition were investigated. The CIGS film growth rate decreased, and the surface roughness of a film increased as the Se flux increased. The [112] crystal orientation was dominant, and metallic crystal phases such as Cu9Ga4 and Cu16In9 in a film were disappearing with increasing Se flux. A solar cell fabricated using a 900‐nm CIGS film showed the power conversion efficiency of 8·6%, the highest value found in a sub‐micron thick CIGS solar cell related to a reactive sputtering process with metallic targets. Copyright © 2011 John Wiley & Sons, Ltd.
Surface Modification of Biopolymers by Argon Plasma and Thermal Treatment
Authors: Slepička Petr , Trostová Simona , Slepičková Kasálková Nikola , Kolská Zdeňka , Sajdl Petr , Švorčík Václav
Published: October 2011

This work deals with the surface characterization of biocompatible polymers: poly(L‐lactide acid) (PLLA) and poly‐4‐methyl‐1‐pentene (PMP). Plasma irradiation and thermal treatment influences the surface wettability, morphology (AFM), chemical composition of surface (XPS) and electrokinetic (zeta) potential. After plasma treatment the surface morphology of PLLA changes dramatically. Plasma treatment generates oxygen groups on the surface of PMP and causes both PMP and PLLA ablation. The thermal treatment accelerates the aging of the polymer surface and dramatically changes the structure of modified PLLA. Plasma treatment improves significantly the cell adhesion and proliferation on the PMP.

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Dysphagia and aspiration in children
Authors: Tutor James D. , Gosa Memorie M.
Published: October 2011

Aspiration is a significant cause of respiratory morbidity and sometimes mortality in children. It occurs when airway protective reflexes fail, especially, when dysphagia is also present. Clinical symptoms and physical findings of aspiration can be nonspecific. Advances in technology can lead to early diagnosis of dysphagia and aspiration, and, new therapeutic advances can significantly improve outcome and prognosis. This report first reviews the anatomy and physiology involved in the normal process of swallowing. Next, the protective reflexes that help to prevent aspiration are discussed followed by the pathophysiologic events that occur after an aspiration event. Various disease processes that can result in dysphagia and aspiration in children are discussed. Finally, the various methods for diagnosis and treatment of dysphagia in children are reviewed. Pediatr Pulmonol. 2012; 47:321–337. © 2011 Wiley Periodicals, Inc.
Pain Impacts on Quality of Life and Interferes with Treatment in Adults with Cystic Fibrosis
Authors: Kelemen Lee , Lee Annemarie L. , Button Brenda M. , Presnell Scott , Wilson John W. , Holland Anne E.
Published: October 2011

Background and purpose

Pain has been reported in cystic fibrosis (CF), but its clinical significance and the physical and psychosocial impact in adults who are clinically stable and acutely unwell have not been well described. The aim of this study was to describe the intensity and location of pain and its relationship with health‐related quality of life (HRQOL) and pain catastrophizing in adults with CF.

Methods

This study was an observational study of adults with CF. Participants completed three questionnaires, the Brief Pain Inventory, Pain Catastrophizing Scale and the CF‐Quality of Life questionnaire, when clinically stable and during an acute exacerbation.

Results

A total of 73 participants were included during a period of clinical stability, with 33 repeating the measurements during an acute illness, with a mean (SD) age of 29 (9) years and forced expiratory volume (FEV1) of 60.5 (24.9)% predicted. Mild pain was reported by 89% of stable participants and 79% of those with exacerbations. Severity of lung disease did not affect prevalence or intensity of pain. Pain interfered with airway clearance therapy during exacerbations (p < 0.012) and exercise regimens when participants were clinically stable (p < 0.002) and was related to a poorer physical function, regardless of clinical status (p < 0.05). Although pain intensity was associated with reduced HRQOL (p < 0.001), only FEV1 and the degree of pain catastrophizing were independent predictors of poorer HRQOL.

Conclusions

Pain is common in adults with CF, irrespective of clinical status, and may interfere with important physiotherapy treatments. Although pain intensity is generally mild, those with a negative emotional response to pain have significantly impaired HRQOL. Copyright © 2011 John Wiley & Sons, Ltd.
Improved RF4CE key agreement approach involving two‐phase key distribution for smart‐convergence home device
Authors: Shon Taeshik , Park James J. (Jong Hyuk) , Park Doo‐Soon
Published: October 2011

This paper presents a robust and secure hybrid connectivity framework for ubiquitous convergence in a home environment. The proposed hybrid connectivity framework is based on various consumer electronics and mobile devices with wireless interfaces such as IEEE 802.15.4 (e.g., radio frequency for consumer electronics (RF4CE) or ZigBee) and IEEE 802.11. In particular, this framework involves an RF4CE‐based WiFi zero‐configuration scheme. It simplifies connectivity by means of secure key distribution and a simple WiFi configuration involving WiFi‐capable devices. To validate our framework, we analyzed the system and security performance using real hardware prototypes. Copyright © 2011 John Wiley & Sons, Ltd.
An empirical energy model for secure Web browsing over mobile devices
Authors: Sharafeddine Sanaa , Arid Amal El
Published: October 2011

Quantifying and modeling energy consumption in mobile devices are essential for developing energy‐aware protocols and energy reduction techniques. In this work, we address the energy requirements for secure Web browsing sessions over handheld mobile devices. The contributions of this work are twofold. On one hand, we present a detailed study based on experimental measurements to quantify the energy consumed by the mobile device during secure Web browsing sessions. This includes the energy consumed due to data transmission/reception, encryption/decryption, hashing in addition to browser processing. On the other hand, we derive an empirical energy consumption model for secure Web browsing as a function of various protocol and device parameters. The developed model can be utilized to identify the various components that affect energy consumption during secure Web browsing sessions, to implement application‐layer energy models in network simulation tools, and to develop adaptive energy‐aware Web browsing protocols. The effectiveness of the developed model is demonstrated via experimental testing on several secure websites. Copyright © 2011 John Wiley & Sons, Ltd.
Diagnosing, Simulating and Improving Business Process Using Cybernetic Laws and the Viable System Model: The Case of a Purchasing Process
Authors: Azadeh Ali , Darivandi Kosar , Fathi Ehsan
Published: October 2011

This paper approaches business process diagnosis from a cybernetic viewpoint. Ashby's law of requisite variety is used to understand deficiencies of business processes. A case of a purchasing process that suffers from low effectiveness and long waiting times of purchase requests is considered to be improved using cybernetic concepts and models. It is discussed that the problems with the process result from a lack of requisite variety. Then, Stafford Beer's viable system model (VSM) is used to ease the problems by balancing the varieties. The static and dynamic aspects of the process are modelled using data flow diagram (DFD) and integrated computer simulation model. It is demonstrated that after applying the VSM, the duration of the process will decrease largely. This is the first study that uses cybernetic law and VSM for improvement of a purchasing process through computer simulation and DFD. Copyright © 2011 John Wiley & Sons, Ltd.
Total System Intervention for System Failures and Its Application to Information and Communication Technology Systems
Authors: Nakamura Takafumi , Kijima Kyoich
Published: October 2011

Total system intervention (TSI) for system failure (SF) is proposed for preventing further occurrences of SFs. TSI is a meta‐methodology in critical system thinking for managing complex and differing viewpoints. First, the authors introduce meta‐methodology called ‘system of SFs (SOSF)’ as a common language among various stakeholders to improve their understanding of SFs. Then, we propose the actual application scenario, or ‘TSI for SFs’. TSI for SF identifies the stakeholders in the failure using a matrix that shows for each stakeholder the entity and/or the factor that is thought to have caused the failure. This helps to clarify the stakeholders' views and to identify stakeholders with opposing views. The SOSF meta‐methodology and related methodologies are used in the course of the subsequent discussion and debate to agree upon who is responsible for the failure and to identify the countermeasures and/or preventative measures to be applied. An application example in ICT engineering demonstrates that using the proposed meta‐methodology as a critical system practice helps prevent future SFs by learning from previous SFs. Three actions were identified for preventing further SFs: close the gap between the stakeholders, introduce absolute goals and enlarge system boundary. Copyright © 2011 John Wiley & Sons, Ltd.
P2X receptors in the gut
Authors: Burnstock Geoffrey
Published: October 2011

Purinergic transmission, which uses ATP and its derivatives as extracellular signaling molecules, is widely distributed throughout all tissues and systems, including the gastrointestinal system. Ionotropic P2X purinoceptors have been identified in various parts of the enteric nervous system, including myenteric, submucosal motor, sensory, and secretomotor neurones, in enteric glial cells and interstitial cells of Cajal. Purinergic mechanosensory transduction, where there is release of ATP from mucosal epithelial cells during distension, stimulating subepithelial nerve endings of intrinsic and extrinsic sensory nerves to modulate peristalsis and initiate nociception. Purinergic signaling in the gut is involved in development, aging, and regeneration of the gut, and the pathophysiology of enteric purinergic signaling in diseases including irritable bowel syndrome, postoperative ileus, esophageal reflux, constipation, diarrhea, diabetes, Chaga's and Hirschprung's diseases. WIREs Membr Transp Signal 2012,1:269–279. doi: 10.1002/wmts.16

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Purification of Extracted Fatty Acids from the Microalgae Spirulina
Authors: Zheng Guangqi , Li Changmo , Guo Lili , Ruo Wenliang , Wang Shuo
Published: October 2011

The fatty acid (FA) analysis of microalgae Spirulina was studied by applying accelerated solvent extraction (ASE) and followed by purification using solid‐phase extraction (SPE). The objective was to develop a sensitive and reliable purification procedure to remove pigment in lipids co‐extracted from Spirulina. Four extraction solvents were used for the ASE lipids extraction. The extraction efficiency was ranked in the following order: chloroform:methanol > dichloromethane:methanol > ethanol > hexane. The major composition of fatty acids were examined. Hexane and chloroform:methanol were compared for the purification step. The amounts of sorbent (Silica gel H), sample, and the volume of eluent were optimized during SPE procedure. This purification step can successfully remove the pigments from extracted lipids. For 0.1 g algae sample, chloroform:methanol (2:1, v/v) was the optimal extraction solvent, 0.3 g silica gel was the optimal amount of sorbent, with 7 mL for the volume of eluent. For hexane as the extraction solvent, 0.5 g algae sample, 0.3 g silica gel was the optimal amount of sorbent, 5 mL was the optimal volume of eluent. The calibration curve was produced comprised from five samples that contained FAME concentrations which was ranged from 0.1 to 10 mg/L (R2 > 0.99). The recoveries of fatty acids were 67.97–134.37%, 74.20–99.13% and 98.34–115.42%, with standard deviations (SD) of three replicate detections ranged from 1.09 to 8.41%.
Der Verhaltensfragebogen bei Entwicklungsstörungen im Erwachsenenalter (VFE-ER)
Authors: Steinhausen Hans-Christoph , Winkler Metzke Christa
Published: October 2011

Zusammenfassung. Hintergrund: Für den Verhaltensfragebogen bei Entwicklungsstörungen (VFE) zur Erfassung von Problemen des Verhaltens und der Emotionen bei Geistiger Behinderung fehlte für die Version im Erwachsenenalter (VFE-ER) bisher noch eine deutsche Normierung. Fragestellung: Überprüfung der psychometrischen Eigenschaften und Normierung des Fragebogens. Methode: Analysen zur Reliabilität und Validität und Normierung anhand der Daten einer Stichprobe von N = 743 Erwachsenen mit Geistiger Behinderung. Ergebnisse: Die bereits für die Kinderversion identifizierten fünf Faktoren der DBC konnten auch für den VFE-ER repliziert werden. Die Validität wurde nachgewiesen und die internen Konsistenzen der fünf Skalen waren gut bis sehr gut. Die Normierung berücksichtigt den Grad der Behinderung. Schlussfolgerungen: Mit dem VFE-ER liegt nun auch für Erwachsene mit Geistiger Behinderung ein sorgfältig konstruiertes und praxistaugliches Verhaltensinventar vor.
Nonlocal buckling behavior of bonded double-nanoplate-systems
Authors: Murmu T. , Sienz J. , Adhikari S. , Arnold C.
Published: October 2011

Buckling behavior of a bonded, uni-axially compressed double-nanoplate-system is investigated in this work. Both the synchronous and asynchronous-type buckling is considered in detail. The two nanoplates are assumed elastically bonded by a polymer resin. The nano-scale effects of nanoplates are dealt with in the analysis by using nonlocal elasticity theory. The theory is utilized for deriving the expressions for a buckling load of a double-nanoplate-system. A simple analytical method is introduced for determining the buckling load of a nonlocal double-nanoplate-system. Explicit closed-form expressions for the buckling load are derived for the case when all four ends are simply supported. Single-layered graphene-sheets are considered for the study. The study highlights that the nonlocal effects considerably influence the buckling behavior of the double-graphene-sheet-system. Unlike the buckling behavior of a single graphene sheet, the double-graphene-sheet-system undergoes both synchronous as well as asynchronous buckling. The nonlocal effects in the double-graphene-sheet-system are higher with increasing values of the nonlocal parameter for the case of synchronous buckling modes than in the asynchronous buckling modes. The increase of the stiffness of the coupling springs in the double-graphene-sheet-system reduces the nonlocal effects during the asynchronous modes of buckling. Different aspect ratios of the double-graphene-sheet-system and higher buckling modes are also considered in the work.
Population inversion of molecular nitrogen in an Ar: N2 mixture by selective resonance-enhanced multiphoton ionization
Authors: Shneider M. N. , Baltuška A. , Zheltikov A. M.
Published: October 2011

Resonance-enhanced multiphoton ionization (REMPI) is shown to offer an attractive strategy for population inversion of molecular nitrogen in an Ar: N2 gas mixture. We present a detailed analysis of the key processes leading to a population inversion of molecular nitrogen in a REMPI-pumped Ar: N2 gas mixture, including a (3 + 1) REMPI of argon atoms, conversion of the REMPI-generated atomic argon ions into molecular ions, and generation of long-lived metastable excited-state argon atoms through dissociative recombination, populating the C3πu states of molecular nitrogen. Population inversion achieved for the second-positive-band laser transitions of molecular nitrogen enables stimulated emission of ultraviolet radiation at 337 nm. A high selectivity of the REMPI process helps to radically reduce the depletion of the working medium through the ionization of N2, providing a pump mechanism that is ideally suited for the creation of a new type of a highly efficient nitrogen laser.
Response of solid Ne upon photoexcitation of a NO impurity: A quantum dynamics study
Authors: Uranga-Piña Ll. , Meier C. , Rubayo-Soneira J.
Published: October 2011

The ultrafast geometrical rearrangement dynamics of NO doped cryogenic Ne matrices after femtosecond laser pulse excitation is studied using a quantum dynamical approach based on a multi-dimensional shell model, with the shell radii being the dynamical variables. The Ne–NO interaction being only weakly anisotropic allows the model to account for the main dynamical features of the rare gas solid. Employing quantum wave packet propagation within the time dependent Hartree approximation, both, the static deformation of the solid due to the impurity and the dynamical response after femtosecond excitation, are analysed. The photoinduced dynamics of the surrounding rare gas atoms is found to be a complex high-dimensional process. The approach allows to consider realistic time-dependent femtosecond pulses and the effect of the pulse duration is clearly shown. Finally, using the pulse parameters of previous experiments, pump-probe signals are calculated and found to be in good agreement with experimental results, allowing for a clear analysis of the ultrafast mechanism of the energy transfer into the solid.
Optical study of the effect of the impurity content on the ferroelectric properties of Er3+ doped SBN glass-ceramic samples
Authors: Haro-González P. , Martín L. L. , Pérez-Rodríguez C. , Martín I. R. , Mujica A.
Published: October 2011

Photoluminescence measurements have been performed on glass ceramic samples of strontium barium niobate doped with Er3+. The glass-ceramic samples were obtained from the precursor glass by thermal treatment and were doped with different contents of Er3+ ions. The average size of the nanocrystals in the samples was about 50 nm. The optical properties of the Er3+ ions were studied upon 532 nm excitation and the luminescence changes were measured as a function of temperature. The study of the luminescence spectra with increasing temperature has allowed us to ascertain the occurrence of the ferroelectric-paraelectric phase transition in the strontium barium niobate nanocrystals embedded in the glass matrix. We have particularly focused on the temperature range around the Curie temperature, when the system undergoes the transition from the ferroelectric phase to the paraelectric phase. Doping of the strontium barium niobate samples results in a change in the measured value of the Curie temperature which induces a change in the ferroelectric properties. It is interesting to note that this phase transition in the nanocrystals immersed in the glass matrix had previously not been detected.
Simultaneous time and wavelength resolved spectroscopy under two-colour near infrared and terahertz excitation
Authors: Bhattacharyya J. , Wagner M. , Zybell S. , Winnerl S. , Stehr D. , Helm M. , Schneider H.
Published: October 2011

Time and wavelength resolved spectroscopy requires optical sources emitting very short pulses and a fast detection mechanism capable of measuring the evolution of the output spectrum as a function of time. We use table-top Ti:sapphire lasers and a free-electron laser (FEL) emitting ps pulses as excitation sources and a streak camera coupled to a spectrometer for detection. One of the major aspects of this setup is the synchronization of pulses from the two lasers which we describe in detail. Optical properties of the FEL pulses are studied by autocorrelation and electro-optic sampling measurements. We discuss the advantages of using this setup to perform photoluminescence quenching in semiconductor quantum wells and quantum dots. Carrier redistribution due to pulsed excitation in these heterostructures can be investigated directly. Sideband generation in quantum wells is also studied where the intense FEL pulses facilitate the detection of the otherwise weak nonlinear effect.
Mapping of femtosecond laser-induced collateral damage by electron backscatter diffraction
Authors: Kumar Anish , Pollock Tresa M.
Published: October 2011

The distribution of the collateral damage beneath craters produced by ultrafast (femtosecond) laser single pulses in a nickel base superalloy single crystal has been analyzed using electron backscatter diffraction. The procedure is based on measurements of the localized crystal rotations caused by the dislocations generated by the shock wave that is produced as an effect of laser pulse interaction with a material. Damage in the form of lattice misorientation created by excess dislocations was negligible at laser fluences up to 2 J/cm2. At higher fluences (5.1-41 J/cm2), the depth of the damage zone beneath the crater increased linearly with laser fluence. Based on lattice misorientation, excess dislocation densities as high as 3 × 1010/cm2 are calculated to be present below the ablated surface in the high fluence regime.
GaN/Al0.5Ga0.5N (11-22) semipolar nanostructures: A way to get high luminescence efficiency in the near ultraviolet range
Authors: Kahouli A. , Kriouche N. , Brault J. , Damilano B. , Vennéguès P. , de Mierry P. , Leroux M. , Courville A. , Tottereau O. , Massies J.
Published: October 2011

The epitaxial growth of GaN/Al0.5Ga0.5N (11-22) semipolar nanostructures and their structural and optical properties are reported. The nanostructure formation results from a strain induced growth process (Stransky-Krastanov-like growth mode). Atomic force microscopy measurements show that depending on the amount of deposited GaN, the nanostructure shape evolves from an island shape to a string shape aligned along the [1-100] direction. Transmission electron microscopy experiments reveal that (11-20) and (11-23) lateral facets are formed, making with the (11-22) growth plane an angle of 32° and 12°, respectively, and giving a very asymmetric nanostructure shape. Photoluminescence (PL) experiments as a function of the excitation power and temperature show that the internal electric field is very low compared to the case of GaN/Al0.5Ga0.5N (0001) polar quantum dots (QDs). As a consequence, the PL emission is strongly shifted towards the UV range compared to polar QDs and the full width at half maximum of the PL peak is drastically reduced. Furthermore, a room temperature PL nanostructure emission 300 times more intense than that of the semi-polar GaN template is obtained despite a large density of defects in the surrounding matrix, as expected for efficient carrier localization inside the nanostructures.
Performance and stability of amorphous InGaZnO thin film transistors with a designed device structure
Authors: Zhang J. , Li X. F. , Lu J. G. , Ye Z. Z. , Gong L. , Wu P. , Huang J. , Zhang Y. Z. , Chen L. X. , Zhao B. H.
Published: October 2011

We propose a specifically designed structure to fabricate thin-film transistors using amorphous indium-gallium-zinc-oxide (a-IGZO) films as the active channel layers. The I-shaped gate electrode is employed to define the channel width, reducing overlaps between the gate and source/drain electrodes. The devices with such a structure exhibit acceptable electrical performance and stability after annealing treatment. The XPS data show that the as-deposited a-IGZO film has not a very dense structure that may induce shallow traps. A shallow trap model is proposed to explain the large threshold voltage shifts of the as-deposited device. Annealing treatment can eliminate these shallow traps and improve the device stability.
Cryogenic electromechanical behavior of multilayer piezo-actuators for fuel injector applications
Authors: Shindo Yasuhide , Narita Fumio , Sasakura Takayoshi
Published: October 2011

This paper examines theoretically and experimentally the electromechanical behavior of multilayer piezo-actuators for fuel injectors at cryogenic temperatures. A thermodynamic model was employed to predict a monoclinic phase. A shift in the morphotropic phase boundary (MPB) between the tetragonal and rhombohedral/monoclinic phases with decreasing temperature was determined, and the temperature dependent piezoelectric coefficients were obtained. Temperature dependent coercive electric field was also predicted based on the domain wall energy. A finite element analysis was then performed to calculate the nonlinear electromechanical fields of the multilayer piezo-actuators from room to cryogenic temperatures, due to the shift in the MPB and polarization switching. In addition, experimental results on the electric field induced strain, which verify the model, were presented.
Including biogeochemical factors and a temporal component in benthic habitat maps: influences on infaunal diversity in a temperate embayment
Authors: Radke Lynda C. , Huang Zhi , Przeslawski Rachel , Webster Ian T. , McArthur Matthew A. , Anderson Tara J. , Siwabessy P. Justy , Brooke Brendan P.
Published: October 2011

Mapping of benthic habitats seldom considers biogeochemical variables or changes across time. We aimed to: (i) develop winter and summer benthic habitat maps for a sandy embayment; and (ii) compare the effectiveness of various maps for differentiating infauna. Patch types (internally homogeneous areas of seafloor) were constructed using combinations of abiotic parameters and are presented in sediment-based, biogeochemistry-based and combined sediment–biogeochemistry-based habitat maps. August and February surveys were undertaken in Jervis Bay, NSW, Australia, to collect samples for physical (% mud, sorting, % carbonate), biogeochemical (chlorophyll a, sulfur, sediment metabolism, bioavailable elements) and infaunal analyses. Boosted decision tree and cokriging models generated spatially continuous data layers. Habitat maps were made from classified layers using geographic information system (GIS) overlays and were interpreted from a biophysical-process perspective. Biogeochemistry and % mud varied spatially and temporally, even in visually homogeneous sediments. Species turnover across patch types was important for diversity; the utility of habitat maps for differentiating biological communities varied across months. Diversity patterns were broadly related to reactive carbon and redox, which varied temporally. Inclusion of biogeochemical factors and time in habitat maps provides a better framework for differentiating species and interpreting biodiversity patterns than once-off studies based solely on sedimentology or video-analysis.
Xenogeneic and endogenous spermatogenesis following transplantation of rat germ cells into testes of immunocompetent mice
Authors: Qu Ning , Naito Munekazu , Li Jun , Terayama Hayato , Hirai Shuichi , Itoh Masahiro
Published: October 2011

Spermatogonial stem cells (SSCs) are the foundation of spermatogenesis, and are characterised by their ability to self-renew and to produce differentiated progeny that form spermatozoa. It has been demonstrated that rat spermatogenesis can occur in the seminiferous tubules of congenitally immunodeficient recipient mice after transplantation of rat SSCs. However, the testis is often viewed as an immune-privileged site in that autoimmunogenic antigens on germ cells do not normally elicit an immune response in situ. In the present study, we tried to transplant rat SSCs into immunocompetent mice after depletion of their own germ cells by means of busulfan. The results showed that some transplanted SSCs could undergo complete spermatogenesis in recipient mouse testes, the rat spermatozoa being detected in 7 of 28 recipient epididymides. A significant increase in mouse spermatozoa was also noted in all 28 epididymides of recipient mice regardless of whether rat spermatozoa were concurrently present or not. These results suggest that transplanted rat SSCs can be tolerated in the testes of immunocompetent mice and that the transplantation of rat SSCs stimulates endogenous spermatogenesis in the recipient mice.
Differential glycolytic and glycogenogenic transduction pathways in male and female bovine embryos produced in vitro
Authors: Garcia-Herreros M. , Aparicio I. M. , Rath D. , Fair T. , Lonergan P.
Published: October 2011

Previous studies have shown that developmental kinetic rates following IVF are lower in female than in male blastocysts and that this may be related to differences in glucose metabolism. In addition, an inhibition of phosphatidylinositol 3-kinase (PI3-K) inhibits glucose uptake in murine blastocysts. Therefore, the aim of this study was to identify and compare the expression of proteins involved in glucose metabolism (hexokinase-I, HK-I; phosphofructokinase-1, PFK-1; pyruvate kinase1/2, PK1/2; glyceraldehyde-3-phosphate dehydrogenase, GAPDH; glucose transporter-1, GLUT-1; and glycogen synthase kinase-3, GSK-3) in male and female bovine blastocysts to determine whether PI3-K has a role in the regulation of the expression of these proteins. Hexokinase-I, PFK-1, PK1/2, GAPDH and GLUT-1 were present in bovine embryos. Protein expression of these proteins and GSK-3 was significantly higher in male compared with female blastocysts. Inhibition of PI3-K with LY294002 significantly decreased the expression of HK-I, PFK-1, GAPDH, GSK-3 A/B and GLUT-1. Results showed that the expression of glycolytic proteins HK-I, PFK-1, GAPDH and PK1/2, and the transporters GLUT-1 and GSK-3 is regulated by PI3-K in bovine blastocysts. Moreover, the differential protein expression observed between male and female blastocysts might explain the faster developmental kinetics seen in males, as the expression of main proteins involved in glycolysis and glycogenogenesis was significantly higher in male than female bovine embryos and also could explain the sensitivity of male embryos to a high concentration of glucose, as a positive correlation between GLUT-1 expression and glucose uptake in embryos has been demonstrated.