bluuebunny/crossref_metadata_2025 huggingface dataset:
Sanierungsverfahren für feuchte‐ und salzbelastetes Mauerwerk Teil 2: Salze und elektroosmotische Strömungsumkehr
Authors: Dettmann A. , Venzmer H.
Published: March 2013

Bei der Anwendung elektroosmotischer Verfahren spielen neben der elektrischen Feldstärke und der Porosität noch eine Reihe weiterer Parameter eine Rolle, die die erwünschten Transportprozesse von Wasser und Salzen beeinflussen oder auch verhindern können.

Bei den hier beschriebenen Untersuchungen zeigte sich, daß der Durchfeuchtungsgrad des Baustoffs (Ziegel) sich ganz wesentlich auf die erzielte Transportmenge auswirkte und daß unterhalb eines bestimmten Durchfeuchtungsgrades keine Elektroosmose mehr stattfand.

Zusätzlich wird diese Transportmenge (Massestromdichte) auch von der Konzentration und Art der im Porenwasser gelösten Salze beeinflußt, wobei starke Versalzungen zu einer verringerten Massestromdichte führen. Höhere Konzentrationen mehrfach geladener Kationen, z. B. Calcium, verursachen sogar eine Umkehrung der elektroosmotischen Strömungsrichtung.

Für die praktische Anwendung müssen darüber hinaus auch die an den Elektroden ablaufenden Elektrolyseerscheinungen, die Änderungen des pH‐Wertes und die Korrosion des Elektrodenmaterials berücksichtigt werden, um Schäden am Bauwerk und an der Anlage zu vermeiden.
Berechnung von Kelleraußenwänden aus Porenbetonmauerwerk
Authors: Flassenberg G.
Published: March 2013

Früher wurden Kellerräume unter anderem zur Lagerung von Lebensmitteln genutzt. Heute dagegen dienen sie immer mehr als Wohnraum, Hausarbeitsraum, Hobbyraum, Spielzimmer, Arbeitszimmer u. ä. Dadurch haben sich auch die bauphysikalischen Anforderungen an Kellerräume, insbesondere die an die wärmetechnischen Eigenschaften des Mauerwerks, maßgeblich erhöht. Hierfür ist Mauerwerk aus Porenbeton besonders geeignet, da der Porenbeton sowohl statische als auch bauphysikalische Aufgaben übernimmt. Einschaliges Porenbetonmauerwerk bietet einen hohen Wärmeschutz, ohne daß zusätzliche Wärmedämmschichten erforderlich sind. Gleichzeitig können alle statischen Anforderungen erfüllt werden.
Zweischalige Außenwände ‐ Überdeckung von Öffnungen in der Außenschale (Verblendschale)
Authors: Altaha N.
Published: March 2013

Dargestellt, erläutert und bewertet werden die verschiedenen Möglichkeiten wie gemauerter Rundbogen, scheitrechter Bogen, Grenadierstürze mit den derzeit verfügbaren Bewehrungssystemen, die Überdeckung mit Stahlprofilen und Fertigteilstürze einschl. Konstruktion, Herstellung und Befestigung.
CuI‐Catalyzed Synthesis of Functionalized Terminal Allenes from 1‐Alkynes
Authors: Luo Hongwen , Ma Shengming
Published: March 2013

Relative to our original protocol that uses CuI (0.5 equiv.), paraformaldehyde (2.5 equiv.), and dicyclohexylamine (1.8 equiv.), a facile and efficient protocol for the gram‐scale synthesis of functionalized terminal allenes by using CuI (7.5–10 mol‐%), paraformaldehyde (1.6 equiv.), and diisopropylamine (1.4 equiv.) has been developed. This method accommodates different functional groups such as hydroxy or carbonyl, and it also performed well in the synthesis of allenylamides and 2,3‐butadien‐1‐ol.
Highly β‐Regioselective Friedel–Crafts Aminoalkylation of Pyrroles with Cyclic Perfluoroalkylated Imines
Authors: Shmatova Olga I. , Shevchenko Nikolay E. , Balenkova Elisabeth S. , Röschenthaler Gerd‐Volker , Nenajdenko Valentine G.
Published: March 2013

A Friedel–Crafts‐type alkylation reaction was studied between various pyrroles and α‐polyfluoroalkylated cyclic imines that were activated by Lewis acids. The reaction proceeded under mild conditions and provided a high yielding synthesis of α‐CF3‐substituted pyrrolidines and piperidines as well as seven‐membered analogues that contained a pyrrole ring. The unpredictably high β‐selectivity for the aminoalkylation of both 1H‐pyrrole and N‐substituted pyrrole was observed as a result of a thermodynamically‐controlled electrophilic substitution reaction. The computational data are in full agreement with the experimental results, which confirmed the observed regioselectivity as a result of the lower energy of the β‐substituted pyrroles that contain α‐trifluoromethyl‐substituted pyrrolidine, piperidine, and azepane rings.
The Construction of All‐Carbon Quaternary Stereocenters by Use of Pd‐Catalyzed Asymmetric Allylic Alkylation Reactions in Total Synthesis
Authors: Hong Allen Y. , Stoltz Brian M.
Published: March 2013

All‐carbon quaternary stereocenters have posed significant challenges in the synthesis of complex natural products. These important structural motifs have inspired the development of broadly applicable palladium‐catalyzed asymmetric allylic alkylation reactions of unstabilized non‐biased enolates for the synthesis of enantioenriched α‐quaternary products. This microreview outlines key considerations in the application of palladium‐catalyzed asymmetric allylic alkylation reactions and presents recent total syntheses of complex natural products that have employed these powerful transformations for the direct, catalytic, enantioselective construction of all‐carbon quaternary stereocenters.
Intramolecular Mizoroki–Heck Reaction in the Regioselective Synthesis of 4‐Alkylidene‐tetrahydroquinolines
Authors: Martínez‐Estíbalez Unai , García‐Calvo Oihane , Ortiz‐de‐Elguea Verónica , Sotomayor Nuria , Lete Esther
Published: March 2013

The Mizoroki–Heck reaction of N‐alkenyl‐substituted 2‐haloanilines is an effective protocol for the synthesis of substituted 4‐alkylidene‐tetrahydroquinoline derivatives, avoiding isomerization and oxidation. When non‐substituted alkenes are used, the regioselectivity of the reaction can be directed towards the formation of an exocyclic or endocyclic double bond by choosing an adequate catalytic system. When the double bond is substituted by an amide moiety, the exocyclic double bond of E geometry is obtained selectively. Thus, this protocol efficiently synthesizes a series of 2‐substituted tetrahydroquinolines with an exo α,β‐unsaturated amide moiety at the C‐4 position.
All‐Thioamidated Homo‐α‐Peptides: Synthesis and Conformation
Authors: Formaggio Fernando , Crisma Marco , Toniolo Claudio , Peggion Cristina
Published: March 2013

Replacement of a peptide bond with its thioamide surrogate is a classical method for the generation of a peptidomimetic with altered spectroscopic, conformational, physicochemical, and biological properties. In this context, we synthesized short series of terminally protected homo‐α‐oligopeptides based on the α‐amino acids Gly, Ala, and Nle, as well as their corresponding fully thioamidated analogues. For the first time, the preparation of the latter compounds was achieved in single‐step fashion through direct thionation of their oxygenated precursors. Using X‐ray diffraction analysis and NMR spectroscopy we were also able to confirm that the thioamidated α‐amino acid residues can easily adopt either folded or fully extended conformations.
Absolute Stereochemical Assignment of SCH 71450, a Selective Dopamine D4 Receptor Antagonist, Through Enantioselective Epimer Synthesis
Authors: Wu Hsin‐Pei , Lu Tai‐Ni , Hsu Nai‐Yun , Chang Che‐Chien
Published: March 2013

The absolute stereochemical assignment of SCH 71450, a selective dopamine D4 receptor antagonist, has been successfully confirmed through enantioselective epimer synthesis. An allyl substituent on the p‐hydroxybenzyl group was demonstrated to be an appropriate protecting group for Noyori Ru‐catalyzed asymmetric transfer hydrogenation of the imine derivative. The construction of the sugar moiety involved a β‐glycosylation reaction assisted by neighboring group participation. By comparison with literature data, the absolute stereochemistry at the C‐1 carbon on the tetrahydroisoquinoline core has been assigned the S configuration.
Association and cumulative effects of GWAS‐identified genetic variants for nonsyndromic orofacial clefts in a Chinese population
Authors: Pan Yongchu , Han Yue , Zhang Hongchuang , Zhou Lian , Li Dandan , Cai Qi , Ma Junqing , Zhang Weibing , Wang Lin
Published: March 2013

A recent genome‐wide meta‐analysis identified six new susceptible genetic variants for nonsyndromic orofacial clefts (NSOC), but it was still unknown whether these newly identified variants were associated with NSOC susceptibility in Chinese populations. In this study, we genotyped these variants in a case‐control study of 602 NSOC cases and 605 controls and found that four of these variants (rs7590268, rs7632427, rs12543318, and rs1873147) were associated with susceptibility to NSOC. We further investigated the cumulative effects of these four variants and found a dose‐dependent increase in risk with the number of variant alleles. Furthermore, an association was observed between rs7590268 and a family history of NSOC. Our results provide confirmative evidence that these risk loci contribute to NSOC susceptibility in Chinese populations. Environ. Mol. Mutagen. 54:261–267, 2013. © 2013 Wiley Periodicals, Inc.
Occurrence of the ribes odorant 3‐sulfanyl‐3‐methylbutyl formate in aged beers
Authors: Tran Thi Thu Hang , Nizet Sabrina , Gros Jacques , Collin Sonia
Published: March 2013

2‐Sulfanyl‐3‐methylbutyl formate and acetate were synthesized without purification steps, quantified with a pulsed flame photometric equimolar detector, and characterized by comparison with commercially available 3‐sulfanyl‐3‐methylbutyl formate and acetate (retention indexes, mass spectra, odour descriptors, and intensities). Both formates exhibited a typical ribes flavour, in contrast to both acetates, which were much more piquant. The sensorial threshold of 3‐sulfanyl‐3‐methylbutyl formate was much lower (57 ng/l in beer, BE‐GC‐LoADS = 0.0006 ng) than those measured for the three other esters. Only 3‐sulfanyl‐3‐methylbutyl formate was perceived at the sniffing port in beer extracts. Concentrations up to 1230 ng/l were measured in pilot beers after 1 month at 20°C, although the compounds are rarely detected in commercial beers with highly oxygen‐protected bottling. Accelerated ageing in the presence of oxygen confirmed the key role of oxygen. Copyright © 2013 John Wiley & Sons, Ltd.
Evaluating Fourier Transform Infrared Spectroscopy as a Non‐Destructive Chert Sourcing Technique
Authors: Parish Ryan Michael , Swihart George Hammond , Li Ying Sing
Published: March 2013

The visual and chemical similarity between some chert types and individual outcrops within the same geologic formation often hinders accurate provenance determination. Fourier Transform Infrared reflectance micro‐spectroscopy (FTIR‐RM) is a nondestructive method demonstrating potential application in chert sourcing. Prior to analysis of archaeological assemblages, the accuracy of the technique and analytical methodology must be tested. The current pilot study examines a geologic sample database of two visually similar chert types (Dover and Fort Payne) in order to determine the technique's ability to differentiate both inter‐ and intra‐outcrop variation. The analysis of these results gives us an improved understanding of the strengths and weaknesses of the FTIR‐RM chert provenance technique and associated statistical methodology.
Analysis of Site Formation History and Potential Disturbance of Stratigraphic Context in Vertisols at the Debra L. Friedkin Archaeological Site in Central Texas, USA
Authors: Driese Steven G. , Nordt Lee C. , Waters Michael R. , Keene Joshua L.
Published: March 2013

Archaeological sites within physically “active” soils, such as Vertisols, are considered suspect by archaeologists because of concern for possible disturbance of stratigraphic context. Pedology, micromorphology, and geochemistry are tools useful for assessing soil mixing. Clay‐rich floodplain soils (Typic Haplusterts) were examined at the Debra L. Friedkin archaeological site along Buttermilk Creek in southwestern Bell County, Texas, USA. The soil contains abundant lithic (mainly chert) artifacts and was assessed for disturbance by vertic soil processes affecting the stratigraphic integrity of the archaeological materials. Vertic features are only weakly to moderately expressed (slickensides and coarse angular blocky peds) in the field, and they are correspondingly weakly expressed in thin section, consisting mainly of stress cutans around detrital grains, microslickensides, and cross‐striated birefringence fabric. Although there is evidence for clay shrink–swell, there has not been significant upward vertical displacement of older materials and no mixing of cultural horizons. Vertical fractures with dark infilling in gilgai microhighs are deep and narrow, and largely preclude downward movement of even small artifacts. Microdebitage is abundant in all levels within the soil profile above culturally sterile layers dated as >15,500 cal. yr B.P. Based on previously published OSL ages and magnetic susceptibility, sedimentation at the site was nearly continuous except for increases during the Younger and Older Dryas, possibly triggered by climate change, and subsequent pedogenesis resulted in uniform element leaching and concentration depth profiles. Vertisols can preserve “undisturbed” Paleoindian archaeological sites and therefore should not be excluded from archaeological surveys and excavations.
Natural hydrocarbon seepage on the continental slope to the east of Mississippi Canyon in the northern Gulf of Mexico
Authors: Rahman Talukder Asrarur , Ross Andrew , Crooke Emma , Stalvies Charlotte , Trefry Christine , Qi Xiubin , Fuentes David , Armand Stephane , Revill Andrew ,   Shipboard Scientific Party
Published: March 2013

From 5 June to 15 September 2010, a multidisciplinary marine survey was undertaken onboard the M/V Ryan Chouest in the region of the BP Deepwater Horizon incident site in the Gulf of Mexico. The primary objective of the survey was the continuous monitoring of hydrocarbon abundance from sea surface down to a maximum depth of 120 m. Compound abundances were inferred using a hydrocarbon sensor array with associated vertical cast system. In order to better understand the potential inputs from natural seepage in the vicinity of the spill, a Simrad EK60 high‐resolution split beam echo sounder, operated at 38 kHz, was included in the survey between 7 July and 15 September 2010. During this period, three fields of natural seeps characterized by hydroacoustic flares were studied in detail. These seep fields are at water depths of approximately 430 m, 880 m, and 1370 m. They are associated with extensive cold seep systems. In particular, the area around Seep Field 1 (the vicinity of Deepwater Horizon) seems to present a vast area of active natural seepages in the Gulf of Mexico. The repeat surveys at two of the fields suggested that the cold seep systems here were active, with expulsions of hydrocarbons into the water column, at least during the periods of our acoustic surveys. Multiple lines of evidence gathered during the survey indicated that the observed hydroacoustic flares at the three fields identified consisted of oily bubble streams of gases of thermogenic origin. However, direct observation and sampling are required to reveal the precise nature of the flares. In the deep water Gulf of Mexico, the formation of a hydrate rim around bubbles seems to be a very important mechanism for the long transport of methane and oil in the water column.
Regulation of Cholesterol And Bile Acid Homeostasis by the Cholesterol 7α-Hydroxylase/Steroid Response Element-Binding Protein 2/Microrna-33A Axis in Mice
Authors: Li Tiangang , Francl Jessica M. , Boehme Shannon , Chiang John Y. L.
Published: March 2013

Bile acid synthesis not only produces physiological detergents required for intestinal nutrient absorption, but also plays a critical role in regulating hepatic and whole-body metabolic homeostasis. We recently reported that overexpression of cholesterol 7α-hydroxylase (CYP7A1) in the liver resulted in improved metabolic homeostasis in Cyp7a1 transgenic (Cyp7a1-tg) mice. This study further investigated the molecular links between bile acid metabolism and lipid homeostasis. Microarray gene profiling revealed that CYP7A1 overexpression led to marked activation of the steroid response element-binding protein 2 (SREBP2)-regulated cholesterol metabolic network and absence of bile acid repression of lipogenic gene expression in livers of Cyp7a1-tg mice. Interestingly, Cyp7a1-tg mice showed significantly elevated hepatic cholesterol synthesis rates, but reduced hepatic fatty acid synthesis rates, which was accompanied by increased 14C-glucose-derived acetyl-coenzyme A incorporation into sterols for fecal excretion. Induction of SREBP2 also coinduces intronic microRNA-33a (miR-33a) in the SREBP2 gene in Cyp7a1-tg mice. Overexpression of miR-33a in the liver resulted in decreased bile acid pool, increased hepatic cholesterol content, and lowered serum cholesterol in mice. Conclusion: This study suggests that a CYP7A1/SREBP2/miR-33a axis plays a critical role in regulation of hepatic cholesterol, bile acid, and fatty acid synthesis. Antagonism of miR-33a may be a potential strategy to increase bile acid synthesis to maintain lipid homeostasis and prevent nonalcoholic fatty liver disease, diabetes, and obesity. (Hepatology 2013;53:1111–1121)
Levels of TNF‐α, soluble TNF receptors (sTNFR1, sTNFR2), and cognition in bipolar disorder
Authors: Doganavsargil‐Baysal Ozge , Cinemre Buket , Aksoy Umut Mert , Akbas Halide , Metin Ozmen , Fettahoglu Cıgıl , Gokmen Zehra , Davran Fatih
Published: March 2013

Objective

Tumor necrosis factor‐alpha (TNF‐α) may play an important role in bipolar disorder (BD) pathogenesis. There is only one study about a relationship between TNF‐α levels and cognitive impairments in BD. The aim of the present study was to see whether TNF‐α, soluble P55 TNF receptor (sTNFR1), and soluble P75 TNF receptor (sTNFR2) levels in BD patients are different from controls and to investigate the relationships between the levels of TNF‐α, sTNFR1, and sTNFR2 and the cognitive functions in euthymic BD patients and controls.

Methods

We assessed 54 BD type I patients and 18 controls by using a battery of neuropsychological tests. Serum TNF‐α levels were measured using a commercially available enzyme‐linked immunosorbent assay, whereas serum sTNFR1 and sTNFR2 levels were measured using a commercially enzyme‐amplified sensitivity immunoassay kit.

Results

We found that levels of sTNFR1 and sTNFR2 in BD patients were different from controls. No difference was detected between the BD group and the control group for levels of TNF‐α. TNF‐α level was found to have a negative correlation with the delayed recall in RAVLT.

Conclusions

High levels of sTNFR1 and sTNFR2 in euthymic patients showed that it may support that proinflammatory process continues in euthymic period. This is the first study which showed increased sTNFR2 levels in euthymic period, which could be interpreted as a compensatory mechanism and again the first which deals with verbal memory. Copyright © 2013 John Wiley & Sons, Ltd.
A NON‐LINEAR MODEL FOR OPTIMAL ALLOCATION OF IRRIGATION WATER AND LAND UNDER ADEQUATE AND LIMITED WATER SUPPLIES: A CASE STUDY IN SOUTHERN ITALY
Authors: Rubino Pietro , Stellacci Anna Maria , Rana Roberta M. , Catalano Maurizia , Caliandro Angelo
Published: March 2013

A non‐linear mathematical optimization model was used to define optimal water and land allocation and optimal cropping patterns for a southern Italy irrigation district. The objective function was based on crop‐water production relations, the parameters of which were derived from an extensive experimental data set including nine arable and vegetable crops. Among production costs, the irrigation binary tariff system adopted in the study region was considered. The study, performed across a wide range of total water supply, identified: (i) optimal water allocation, by keeping crop surface constant; (ii) optimal cropping patterns, when allocation of available land was also investigated. When a fixed surface was allocated to each crop, and total water supply was not limiting, maximum return was achieved by providing the greatest fraction of available water to vegetable crops (pepper, tomato, eggplant, beans), with seasonal volumes corresponding to full restitution of irrigation water requirements (from 6758 to 3571 m3 ha‐1), while assigning volumes equal to 78, 62, 48 and 41% of water requirements to summer and spring maize, autumnal and spring sugar beet. When the allocation of water and land was investigated simultaneously, optimal cropping patterns and seasonal volumes were identified. The latter varied as a function of crop and total water supply but also, at a given supply, for the same crop. Copyright © 2013 John Wiley & Sons, Ltd.
Using Apps to Support Disciplinary Literacy and Science Learning
Authors: Castek Jill , Beach Richard
Published: March 2013

Apps, specialized programs used on mobile computers, can be used in innovative ways to enhance science and literacy learning. With the skilled guidance of their teachers, students can exploit app affordances for learning and acquire disciplinary literacies unique to science. This article showcases apps that help students to access information, make sense of it, and create their own products that include rich visual representations. We also describe teaching approaches that support the close reading of science texts through the use of note‐taking and annotation apps. Classroom examples that are featured illustrate that these app affordances are not simply in the apps, but rather, fostered by how the teachers exploit these affordances to achieve their own particular learning objectives. As we become more familiar with new apps as educational tools, we need to be mindful about how these tools strategically in ways that best enhance our students’ own learning.
Putting Two and Two Together: Middle School Students' Morphological Problem‐Solving Strategies For Unknown Words
Authors: Pacheco Mark B. , Goodwin Amanda P.
Published: March 2013

FREE author podcast
Literacies in the Body
Authors: Jones Stephanie
Published: March 2013

In this commentary, the the author invites readers to consider the body and its central place in literacy pedagogy, practice and research. She emphasizes two interrelated paths for teachers and researchers interested in literacies to tend to the body: (1) the ways literacies are engaged and cultivated for making senseofbodies, and (2) the literacies embedded in, performed through, and experiencedasbodies. Drawing on poststructural theories and her analysis of round robin reading, the author reminds readers that literacies are not inherently good, and educators concerned with issues of inequities and injustice can study and reimagine the literacies in bodies that propel too many of us forward in an automaton fashion.
Measuring Adolescents' Attitudes Toward Reading: A Classroom Survey
Authors: Conradi Kristin , Jang Bong Gee , Bryant Camille , Craft Aggie , McKenna Michael C.
Published: March 2013

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Effects of freezing/thawing on the mechanical properties of decellularized lungs
Authors: Nonaka Paula N. , Campillo Noelia , Uriarte Juan J. , Garreta Elena , Melo Esther , de Oliveira Luis V. F. , Navajas Daniel , Farré Ramon
Published: March 2013

Lung bioengineering based on decellularized organ scaffolds is a potential alternative for transplantation. Freezing/thawing, a usual procedure in organ decellularization and storage could modify the mechanical properties of the lung scaffold and reduce the performance of the bioengineered lung when subjected to the physiological inflation‐deflation breathing cycles. The aim of this study was to determine the effects of repeated freezing/thawing on the mechanical properties of decellularized lungs in the physiological pressure–volume regime associated with normal ventilation. Fifteen mice lungs (C57BL/6) were decellularized using a conventional protocol not involving organ freezing and based on sodium dodecyl sulfate detergent. Subsequently, the mechanical properties of the acellular lungs were measured before and after subjecting them to three consecutive cycles of freezing/thawing. The resistance (RL) and elastance (EL) of the decellularized lungs were computed by linear regression fitting of the recorded signals (tracheal pressure, flow, and volume) during mechanical ventilation. RL was not significantly modified by freezing‐thawing: from 0.88 ± 0.37 to 0.90 ± 0.38 cmH2O·s·mL−1 (mean ± SE). EL slightly increased from 64.4 ± 11.1 to 73.0 ± 16.3 cmH2O·mL−1 after the three freeze‐thaw cycles (p = 0.0013). In conclusion, the freezing/thawing process that is commonly used for both organ decellularization and storage induces only minor changes in the ventilation mechanical properties of the organ scaffold. © 2013 Wiley Periodicals, Inc. J Biomed Mater Res Part A: 102A: 413–419, 2014.
In vitro and in vivo degradation behavior of n‐HA/PCL‐Pluronic‐PCL polyurethane composites
Authors: Fu Shao‐Zhi , Meng Xiao‐Hang , Fan Juan , Yang Ling‐Lin , Lin Sheng , Wen Qing‐Lian , Wang Bi‐Qiong , Chen Lan‐Lan , Wu Jing‐Bo , Chen Yue
Published: March 2013

Scaffolds for bone tissue engineering applications should have suitable degradability in favor of new bone ingrowth after implantation into bone defects. In this study, degradation behavior of polyurethane composites composed of triblock copolymer poly(caprolactone)–poluronic–poly(caprolactone) (PCL–Pluronic–PCL, PCFC) and nanohydroxyapatite (n‐HA) was investigated. The water contact angle and water absorption were measured to reveal the effect of n‐HA content on the surface wettability and swelling behavior of the n‐HA/PCFC composites, respectively. The weight loss in three degradation media with pH value of 4.0, 7.4, and 9.18 was also studied accordingly. Fourier transform infrared analysis, differential scanning calorimeter, X‐ray diffraction, thermal‐gravimetric analysis, and scanning electron microscopy were used to investigate the change of chemical structure and micromorphology after the n‐HA/PCFC composite with 30% HA was degraded for different time intervals. Meanwhile, in vivo degradation was conducted by subcutaneous implantation. The weight loss and morphology change during observation periods were also studied. © 2013 Wiley Periodicals, Inc. J Biomed Mater Res Part A: 102A: 479–486, 2014.
Osteoblastic cell response on biphasic fluorhydroxyapatite/strontium‐substituted hydroxyapatite coatings
Authors: Yin Ping , Feng Fang Fang , Lei Ting , Zhong Xiao Huan , Jian Xin Chun
Published: March 2013

Fluorhydroxyapatite/strontium‐substituted hydroxyapatite (FHA/SrHA) biphasic coatings with F and Sr elements incorporated simultaneously into one coating layer were prepared on titanium substrate via colloidal sol–gel method. The bioactivity of the as‐prepared FHA/SrHA biphasic coatings was evaluated in vitro by immersion in simulated body fluid (SBF). All the biphasic coatings exhibited great ability to induce apatite precipitation on their surfaces. In vitro cell responses were evaluated using osteoblast‐like MG63 cells in terms of cell proliferation and differentiation (alkaline phosphatase activity and osteocalcin level). The biphasic coatings show significantly positive effects on the viability and functional activity of osteoblastic cells with clear evidence that an optimum SrHA amount dose exists, indicating that the coexistence of FHA and SrHA had a synergistic stimulatory effect. This finding suggests the potential use of this colloidal sol–gel derived FHA/SrHA biphasic coatings for hard tissue applications. © 2013 Wiley Periodicals, Inc. J Biomed Mater Res Part A: 102A: 621–627, 2014.
Tonoplast Na+/H+ antiporters of newly developed maize (Zea mays) hybrids contribute to salt resistance during the second phase of salt stress
Authors: Pitann Britta , Mohamed Abdel‐Kareem , Neubert Anja B. , Schubert Sven
Published: March 2013

To investigate the role of tonoplast Na+/H+ antiporters (ZmNHX) in salt‐stress resistance newly developed maize (Zea mays L.) SR hybrids and cv. Across 8023 were tested under low (50 mM NaCl) and high salinity (200 mM NaCl). Resistance to Na+ toxicity was monitored in terms of shoot growth and number of necrotic leaf spots. At high salinity, the SR hybrids showed better shoot growth than Across 8023. SR 03 and SR 05 had a lower number of necrotic spots per leaf compared to SR 20 and Across 8023. Based on these results, SR 03 and SR 05 were classified as salt‐resistant, and SR 20 and Across 8023 as salt‐sensitive genotypes. At 200 mM NaCl, the salt‐resistant hybrids SR 03 and SR 05 showed a significant upregulation of the tonoplast Na+/H+ antiporter (ZmNHX) in leaves compared with Across 8023 and SR 20. The salt stress–induced increase in transcription of ZmNHX may lead to enhanced tonoplast Na+/H+ antiport in leaves for SR 03 and SR 05. Hence, sequestration of Na+ into leaf vacuoles contributes to salt resistance of these genotypes by protecting the cytoplasm from Na+ toxicity. Relative transcription of ZmNHX in roots was only increased in SR 20, which may explain the efficient Na+ exclusion from shoots of SR 20.
Depressive Symptoms in Bereaved Parents in the 2008 Wenchuan, China Earthquake: A Cohort Study
Authors: Liu Wumei , Fan Fang , Liu Jianghong
Published: March 2013

This study sought to expand the literature on bereavement and response to natural disasters by reporting the prevalence, severity, and correlates of depressive symptoms among bereaved and nonbereaved parents of the 2008 Wenchuan Earthquake in China. Bereaved (n = 155) and nonbereaved (n = 35) parents from the Xiang'e township in China were interviewed at 18 months (Wave 1) and 24 months (Wave 2) following the earthquake. From Wave 1 to Wave 2, rates of probable depression fell for both bereaved (65.8% to 44.5%) and nonbereaved parents (34.3% to 20.0%). The depression index of both groups also decreased, but only significantly among bereaved parents. Of bereaved parents, those with fewer years of education had more severe symptoms at both waves. Depressive symptom severity of bereaved mothers improved over time, but that of bereaved fathers remained unchanged. Not becoming pregnant again after the earthquake was significantly linked to worse depressive symptoms in both waves, but this was not significant when age was added to the model. Bereaved parents may need more postearthquake supportive services, with fathers, individuals with fewer years of education, and parents who are not able to become pregnant again after the earthquake being particularly vulnerable.
Kinetic Study of the CCl2 Radical Recombination Reaction by Laser‐Induced Fluorescence Technique
Authors: Gómez Nicolás D. , D'Accurso Violeta , Freytes V. Mariana , Manzano Francisco A. , Codnia Jorge , Azcárate M. Laura
Published: March 2013

An experimental setup that coupled IR multiple‐photon dissociation (IRMPD) and laser‐induced fluorescence (LIF) techniques was implemented to study the kinetics of the recombination reaction of dichlorocarbene radicals, CCl2, in an Ar bath. The CCl2 radicals were generated by IRMPD of CDCl3. The time dependence of the CCl2 radicals’ concentration in the presence of Ar was determined by LIF. The experimental conditions achieved allowed us to associate the decrease in the concentration of radicals to the self‐recombination reaction to form C2Cl4. The rate constant for this reaction was determined in both the falloff and the high‐pressure regimes at room temperature. The values obtained were k0 = (2.23 ± 0.89) × 10−29 cm6 molecules−2 s−1 and k∞ = (6.73 ± 0.23) × 10−13 cm3 molecules−1 s−1, respectively.
Kinetics and Mechanism of the Pyridinolyses of O‐Methyl and O‐Ethyl Phenyl Phosphonochloridothioates in Acetonitrile
Authors: Ul Hoque Md. Ehtesham , Lee Hai Whang
Published: March 2013

Kinetic studies on the reactions of O‐methyl (2) and O‐ethyl (3) phenyl phosphonochloridothioates with X‐pyridines have been carried out in acetonitrile at 35.0°C. The pyridinolysis rates of 2 are slightly faster than those of 3. The substituent effects of X on the pyridinolysis rates of 2 and 3 are similar. The Hammett and Brönsted plots with X in the nucleophiles are biphasic concave upward with a break point at X = 3‐Ph for both substrates. The stepwise mechanism with rate‐limiting leaving group departure from the intermediate is proposed based on the βX values and biphasic concave upward free energy relationship for both substrates. The biphasic concave upward free energy relationships are rationalized by a frontside nucleophilic attack TSf with more basic pyridines and backside attack TSb with less basic pyridines for both substrates.
Tympanic membrane repair using silk fibroin and acellular collagen scaffolds
Authors: Shen Yi , Redmond Sharon L. , Teh Bing Mei , Yan Sheng , Wang Yan , Atlas Marcus D. , Dilley Rodney J. , Zheng Minghao , Marano Robert J.
Published: March 2013

Objectives/Hypothesis

To evaluate the efficacy of silk fibroin scaffolds (SFS) and acellular collagen scaffolds (ACS) for the repair of tympanic membrane (TM) in a guinea pig acute perforation model.

Study Design

Experimental animal research.

Methods

Seventy‐two albino guinea pigs underwent perforation of the right TM and were divided into four experimental groups (n = 18). The perforations were repaired with SFS, ACS, and paper patch using onlay myringoplasty, or they were allowed to heal spontaneously (control). An additional group of 10 guinea pigs without perforation or scaffold was allocated as a normal TM group. Guinea pigs in each experimental group (n = 6) were evaluated at 7, 14, and 28 days following surgery. TM structural healing was evaluated by otomicroscopy and histology, and functional hearing was analyzed by auditory brainstem responses (ABR). Prior to the study, mechanical properties of SFS and ACS were investigated.

Results

Tensile strength and elasticity of SFS and ACS were within the known range for human TM. Based on otologic and histologic evaluation, TMs treated with SFS or ACS showed complete closure of the perforation at an earlier stage, with a trilaminar structure and more uniform thickness compared to paper patch and control treated groups. ABR assessment demonstrated that SFS or ACS treatment facilitated a faster restoration of hearing function compared to paper patch and control groups.

Conclusion

The results of this study show that SFS and ACS are effective graft materials and may be utilized as alternatives to current grafts for TM repair.

Level of Evidence

N/A. Laryngoscope, 123:1976–1982, 2013
A nullstellensatz and a positivstellensatz for ordered differential fields
Authors: Brouette Quentin
Published: March 2013

We use the model completeness and axiomatisation of the theory of closed ordered differential fields to give a differential version of Dubois, Krivine and Risler's nullstellensatz and Stengle's positivstellensatz for ordered fields.
Bohr's phenomenon for analytic functions and the hyperbolic metric
Authors: Muhanna Yusuf Abu , Ali Rosihan M.
Published: March 2013

A link is established between Bohr's inequality for classes of analytic functions and the hyperbolic metric. The classes considered consist of analytic functions mapping the unit disk respectively into the right half‐plane, the slit region, and to the exterior of the unit disk.
The behavior of conditional Wiener integrals on product Wiener space
Authors: Choi Jae Gil , Skouge David , Chang Seung Jun
Published: March 2013

In this paper we first investigate the behavior of conditional Wiener integrals on product Wiener spaces and then proceed to establish a Fubini theorem for conditional Wiener integrals. We then define a very general multiple conditional analytic Fourier‐Feynman transform and a multiple conditional analytic convolution product for functionals on Wiener space and then establish a relationship between them. Next we obtain a basic formula for the conditional Wiener integral involving the first variation and the n‐dimensional Wiener directional derivative. Finally we establish several evaluation formulas for conditional Wiener and Feynman integrals involving the n‐dimensional Wiener directional derivative of functionals on Wiener space.
Access to Intrinsically Glucoside‐Based Microspheres with Boron Affinity
Authors: Vogt Andrew P. , Tischer Thomas , Geckle Udo , Greiner Alexandra M. , Trouillet Vanessa , Kaupp Michael , Barner Leonie , Hofe Thorsten , Barner‐Kowollik Christopher
Published: March 2013

Intrinsically glucoside‐based microspheres are prepared in olive oil via a water in oil inverse suspension polymerization. The microspheres are characterized by scanning electron microscopy (SEM), Fourier transform infrared (FTIR) microscopy, and X‐ray photoelectron spectroscopy (XPS), evidencing the intrinsic glucose character of the spheres. A novel boronic acid fluorescent molecule was subsequently conjugated to the microspheres in an aqueous environment, exhibiting the spatial and uniform distribution of glucoside as well as the affinity of the microspheres to bind with boron, evidenced via fluorescence spectroscopy measurements.

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Truncation of type IV pilin induces mucoidy in Pseudomonas aeruginosa strain PAO579
Authors: Ryan Withers T. , Heath Damron F. , Yin Yeshi , Yu Hongwei D.
Published: March 2013

Pseudomonas aeruginosa is a Gram negative, opportunistic pathogen that uses the overproduction of alginate, a surface polysaccharide, to form biofilms in vivo. Overproduction of alginate, also known as mucoidy, affords the bacterium protection from the host's defenses and facilitates the establishment of chronic lung infections in individuals with cystic fibrosis. Expression of the alginate biosynthetic operon is primarily controlled by the alternative sigma factor AlgU (AlgT/σ22). In a nonmucoid strain, AlgU is sequestered by the transmembrane antisigma factor MucA to the cytoplasmic membrane. AlgU can be released from MucA via regulated intramembrane proteolysis by proteases AlgW and MucP causing the conversion to mucoidy. Pseudomonas aeruginosa strain PAO579, a derivative of the nonmucoid strain PAO1, is mucoid due to an unidentified mutation (muc‐23). Using whole genome sequencing, we identified 16 nonsynonymous and 15 synonymous single nucleotide polymorphisms (SNP). We then identified three tandem single point mutations in the pilA gene (PA4525), as the cause of mucoidy in PAO579. These tandem mutations generate a premature stop codon resulting in a truncated version of PilA (PilA108), with a C‐terminal motif of phenylalanine‐threonine‐phenylalanine (FTF). Inactivation of pilA108 confirmed it was required for mucoidy. Additionally, algW and algU were also required for mucoidy of PAO579. Western blot analysis indicated that MucA was less stable in PAO579 than nonmucoid PAO1 or PAO381. The mucoid phenotype and high PalgU and PalgD promoter activities of PAO579 require pilA108, algW, algU, and rpoN encoding the alternative sigma factor σ54. We also observed that RpoN regulates expression of algW and pilA in PAO579. Together, these results suggest that truncation in type IV pilin in P. aeruginosa strain PAO579 can induce mucoidy through an AlgW/AlgU‐dependent pathway.
The VPS35 gene and Parkinson's disease
Authors: Deng Hao , Gao Kai , Jankovic Joseph
Published: March 2013

Parkinson's disease (PD), the second most common age‐related neurodegenerative disease, is characterized by loss of dopaminergic and nondopaminergic neurons, leading to a variety of motor and nonmotor symptoms. In addition to environmental factors, genetic predisposition and specific gene mutations have been shown to play an important role in the pathogenesis of this disorder. Recently, the identification of the vacuolar protein sorting 35 homolog gene (VPS35), linked to autosomal dominant late‐onset PD, has provided new clues to the pathogenesis of PD. Here we discuss the VPS35 gene, its protein function, and various pathways involved in Wnt/β‐catenin signaling and in the role of DMT1 mediating the uptake of iron and iron translocation from endosomes to the cytoplasm. Further understanding of these mechanisms will undoubtedly provide new insights into the pathogenic mechanisms of PD and may lead to prevention and better treatment of the disorder. © 2013 Movement Disorder Society
Biochemical phenotype of a common disease‐causing mutation and a possible therapeutic approach for the phosphomannomutase 2‐associated disorder of glycosylation
Authors: Andreotti Giuseppina , Pedone Emilia , Giordano Assunta , Cubellis Maria Vittoria
Published: March 2013

Phosphomannomutase 2 (PMM2) deficiency represents the most frequent type of congenital disorders of glycosylation. For this disease there is no cure at present. The complete loss of phosphomannomutase activity is probably not compatible with life and people affected carry at least one allele with residual activity. We characterized wild‐type PMM2 and its most common hypomorphic mutant, p.F119L, which is associated with a severe phenotype of the disease. We demonstrated that active species is the dimeric enzyme and that the mutation weakens the quaternary structure and, at the same time, affects the activity and the stability of the enzyme. We demonstrated that ligand binding stabilizes both proteins, wild‐type and F119L‐PMM2, and promotes subunit association in vitro. The strongest effects are observed with glucose‐1,6‐bisphosphate (Glc‐1,6‐P2) or with monophosphate glucose in the presence of vanadate. This finding offers a new approach for the treatment of PMM2 deficiency. We propose to enhance Glc‐1,6‐P2 concentration either acting on the metabolic pathways that control its synthesis and degradation or exploiting prodrugs that are able to cross membranes.
Broadband antenna with capacitive‐coupling for mobile handsets
Authors: Yoon Cheol , Hwang Sun‐Gook , Lee Gi‐Chan , kim Woo‐Su , Lee Hwa‐Choon , Park Hyo‐Dal
Published: March 2013

In this article, a broadband antenna for LTE, GSM, DCS, PCS, and WCDMA is proposed.The antenna consists of a T‐shape strip and a shorted strip with capacitive coupling is excited. The capacitively coupled shorted strip shows resonance at the lower band, and the T‐shape strip presents good matching at the higher band because the characteristics of input impedance are affected by the coupling. Moreover, by optimizing the dimensions of the L‐shape strip, the total bandwidth of the antenna can be greatly improved. © 2013 Wiley Periodicals, Inc. Microwave Opt Technol Lett 55:1308–1312, 2013; View this article online at wileyonlinelibrary.com. DOI 10.1002/mop.27532
Highly compact UWB printed monopole antennas with different ground plane structures
Authors: Thwin Su Sandar
Published: March 2013

This article presents highly compact‐sized, low‐profile, and planar monopole antennas for ultra‐wideband (UWB) operations.The two proposed antennas' structures consist of the circular radiating patch with microstrip‐fed monopole structure and coplanar waveguide‐fed (CPW) monopole structure. By properly selecting positions and dimensions of the embedded slots in the radiating patch and ground planes, wide impedance bandwidths are achieved. The numerical and experimental results show that the designed antennas can operate over UWB band groups 2, 3, 4, and 5 and satellite communications. The designed antennas have the simple uniplanar structures and occupy small size of 11 × 16 mm2 including the finite ground CPW feeding mechanism and partial ground microstrip line feeding mechanism. In addition, acceptable radiation characteristics are obtained over the operating bands. © 2013 Wiley Periodicals, Inc. Microwave Opt Technol Lett 55:1191–1196, 2013; View this article online at wileyonlinelibrary.com. DOI 10.1002/mop.27538
An efficient de‐embedding technique for evaluating the S‐parameters of microwave circuits and printed antennas
Authors: Bianconi Giacomo , Pelletti Chiara , Mittra Raj
Published: March 2013

In this article, we present an efficient de‐embedding technique based on the characteristic basis function method for an accurate evaluation of the “generalized S‐parameters” for microstrip circuits and antennas etched on layered media. Numerical examples are provided to demonstrate the reliability and computational efficiency of the described procedure. © 2013 Wiley Periodicals, Inc. Microwave Opt Technol Lett 55:1266–1270, 2013; View this article online at wileyonlinelibrary.com. DOI 10.1002/mop.27549
Bidirectional rectangular ring antenna for coal mine/tunnel communication
Authors: Liu Wendong , Zhang Zhijun , Feng Zhenghe
Published: March 2013

A bidirectional antenna, which is useful in coal mine or tunnel wireless communication, is proposed in this article. The antenna consists of a probe excited rectangular ring. The dimensions of the rectangular ring are 147 × 20 × 40 mm3 (0.45λ × 0.06λ × 0.12λ). The length of the feeding probe is 15 mm (0.045λ). The measured −10 dB bandwidth is ∼14 MHz (910–924 MHz), and the corresponding peak gain is 5.8 dBi. Radiation patterns are measured and compared to the simulation results. The proposed bidirectional antenna has the advantages of low cost, low‐profile, easy fabrication, small cross‐section to the ventilation direction, and good bidirectional radiation. © 2013 Wiley Periodicals, Inc. Microwave Opt Technol Lett 55:1412–1416, 2013; View this article online at wileyonlinelibrary.com. DOI 10.1002/mop.27552
Electrically coupled loop antenna as a dual for the planar inverted‐f antenna
Authors: Manteghi Majid
Published: March 2013

The electrically coupled loop antenna is presented as a dual for the existing planar inverted F antenna (PIFA).The basic drawbacks of the PIFA are low radiation efficiency and high electric field in the near zone. The dual antenna has high radiation efficiency and low electric field in the near zone that makes it a good candidate for cellphones and implanted antenna applications. The antenna is designed and simulated using HFSS and the results are compared with the measured data. © 2013 Wiley Periodicals, Inc. Microwave Opt Technol Lett 55:1409–1412, 2013; View this article online at wileyonlinelibrary.com. DOI 10.1002/mop.27553
A novel printed microstrip antenna with frequency reconfigurable characteristics for bluetooth/WLAN/WIMAX applications
Authors: Pan Yong , Liu Kaihua , Hou Ziye
Published: March 2013

A novel printed microstrip reconfigurable antenna with three switchable frequencies is proposed. The proposed microstrip‐fed antenna was fabricated on FR4 substrate and mainly consists of four semicircular rings, one circular ring, one cross strip, and one defected ground plane. The uniqueness of this design is that various groups of operating frequencies can be selected electronically by controlling two PIN diode switches purposefully. Several kinds of reconfigurable resonant frequencies covering the bands of 2.30–2.53 GHz, 3.19–3.81 GHz, and 4.68–6.03 GHz, which can be applied in the systems of Bluetooth (2.4–2.484 GHz), WiMAX (3.3–3.6 GHz), and WLAN (2.4–2.484 GHz, 5.15–5.35 GHz, and 5.725–5.875 GHz), are achieved. Meanwhile, the presented antenna has nearly omnidirectional radiation patterns and relatively high gains. By comparing the simulated and measured results, a good agreement is obtained. © 2013 Wiley Periodicals, Inc. Microwave Opt Technol Lett 55:1341–1345, 2013; View this article online at wileyonlinelibrary.com. DOI 10.1002/mop.27556
A modified balanced antipodal vivaldi antenna with improved radiation characteristics
Authors: Juan Lei , Guang Fu , Lin Yang , Demin Fu
Published: March 2013

A modified corrugated balanced antipodal Vivaldi antenna with director (CBAVA‐D) is presented for ultrawideband (UWB) applications in this article. The main features of the antenna, besides an UWB width are high gain, low cross‐polarization, and excellent group delay. The new antenna concept, including the hybrid structure of exponential tapered corrugation edge and curving dielectric director with high‐dielectric constant is demonstrated, based on simulation and measurement results in both frequency and time domain. The antenna prototype input match is better than −10 dB, the maximal gain of 12.6 dB and the cross‐polarization level less than −30 dB in the main beam direction at 1.5–15 GHz band are achieved. In the time domain measured group delay with variation less than ±0.25 ns in the whole operating band is also obtained and exhibited. © 2013 Wiley Periodicals, Inc. Microwave Opt Technol Lett 55:1321–1325, 2013; View this article online at wileyonlinelibrary.com. DOI 10.1002/mop.27558