bluuebunny/crossref_metadata_2025 huggingface dataset:
A road tunnel in difficult geology with cross‐sections up to 300 m2 / Straßentunnel in schwieriger Geologie mit Querschnitten bis zu 300 m2
Authors: Längle Thomas , Käppeli Lukas
Published: December 2010

The 4.2 km Eyholz tunnel is part of the autobahn A9 and is the essential element in the bypass of Visp in the canton Valais, Switzerland. The tunnel passes through geologically problematic and also tectonically highly stressed zones (Rhone‐Simplon fault).

The excavation of the two two‐lane bores is being performed conventionally, by blasting and also in loose material. The interesting structures include the underground junction caverns, where slip roads to join and leave the autobahn are included in the tunnel, resulting in cross‐sections of up to 300m2 having to be excavated.

The overburden areas near the portals were excavated with tunnel excavators under the protection of elaborate jetted canopies. The two tunnel bores are being excavated in parallel and are connected with crosscuts every 270 m. As is typical for recent Swiss autobahn tunnels, a service duct is constructed under the carriageway. The inner lining of the main bores is progressing at the same time as the excavation and also the lining of the cavern with in‐situ concrete. The first bore should open for traffic in 2013.

Der 4,2 km lange Autobahntunnel Eyholz ist Teil der Autobahn A9 und bildet das Kernstück der Umfahrung Visp im Kanton Wallis, CH. Der Tunnel befindet sich in geologisch schwierigen, und zusätzlich tektonisch stark beanspruchten Zonen (Rhone‐Simplon Störung).

Die Ausbruchsarbeiten der beiden Doppelspurröhren werden konventionell, sowohl im Spreng‐ als auch im Lockermaterialvortrieb ausgeführt. Bautechnisch interessante Bauwerke sind unter anderem die unterirdischen Verzweigungskavernen. Hier wurden aus Platzgründen Ein‐ und Ausfahrtsspuren in den Tunnel verlegt, wodurch Ausbruchsquerschnitte bis 300m2 aufzufahren waren.

Die Überlagerungsbereiche der Portalstrecken wurden teilweise mit aufwändigen Jettschirmen gesichert und im Baggervortrieb ausgebrochen. Beide Tunnelröhren werden parallel ausgebrochen und sind alle 270 m mit Querschlägen miteinander verbunden. Typisch für die Schweizer Autobahnen in jüngerer Zeit ist ein, unter der Fahrbahn angeordneter Werkleitungskanal. Gleichzeitig zum Vortrieb laufen der Innenausbau der Hauptröhren sowie der Ausbau der Kavernen in Ortbeton. 2013 soll die erste Röhre ans Netz gehen.
Tunnel refurbishment – a job with surprises / Tunnelsanierung – eine Arbeit mit Überraschungen
Authors: Schwab Peter , Neumayer Jürgen
Published: December 2010

The term tunnel refurbishment is mostly understood to mean the upgrading or improvement of underground cavity structures like rail or road tunnels and also structures for hydropower stations and underground operations. Before starting refurbishment measures, it is absolutely necessary to survey the exact condition of the existing structure. This survey of the actual condition cannot be based on the assumption that the available design documents correspond to the facts on site. It is therefore sensible, or even essential, to call on engineers, whose experience goes back to the time the relevant construction methods were in use and who can visualise the ideas of the former state of technology. This basic knowledge is necessary in order to plan adequate and correct investigations so that certain results can be obtained for the design of the refurbishment works.

Experience shows that false assumptions about the existing structure have resulted in extensive design changes during the construction phase and severe delays with considerable cost effects. The examples in this article show that different refurbishment measures have to be approached differently and that in the future, the consequences of tolerances should be planned and clearly specified according to the specific nature of the task.

Unter dem Begriff Tunnelsanierung versteht man meist die Ertüchtigung oder Verbesserung von untertägigen Hohlraumbauten wie Verkehrstunnel der Bahn und Straße ebenso auch Bauwerke für Wasserkraftanlagen und untertägige Betriebe. Vor Angriff der Sanierungsmaßnahmen ist es unbedingt notwendig, dass der genaue Zustand des vorhandenen Bauwerks erhoben wird. Bei der Erhebung des Ist‐Zustands kann man nicht davon ausgehen, dass die vorhandenen Planunterlagen den Tatsachen vor Ort entsprechen. Es wird daher sinnvoll, wenn nicht sogar notwendig sein, sich Baufachleuten zu bedienen, deren Erfahrung bis in die Herstellungszeit der damaligen Baumethode zurückreicht und die sich die Ansichten über den Stand der damaligen Technik vorstellen können. Dieses Grundwissen ist notwendig, um ausreichende und richtige Erkundungen so zu setzen, dass gesicherte Erkenntnisse für die Planung der notwendigen Sanierungsmaßnahmen ermittelt werden können.

In der Vergangenheit hat sich gezeigt, dass durch falsche Annahmen über den tatsächlichen Bestand weitreichende Planungsänderungen in der Bauausführungsphase vorgenommen mussten und dadurch mehrfach gestörte Bauabläufe mit erheblichen Kostenauswirkungen die Folge waren. Die Beispiele in diesem Beitrag zeigen, dass man an die verschiedenen Sanierungsmaßnahmen unterschiedlich herangehen muss und dass in Zukunft die Auswirkungen der Toleranzen geplant und eindeutig vorgegeben werden müssen.
Tunnelling in Hungary – The M6 chain of tunnels / Tunnelbau in Ungarn – Tunnelkette M6
Authors: Gamper Christian , Theurl Mario
Published: December 2010

In Hungary, a motorway network is being built in a star shape starting in Budapest. The M6 motorway runs southward from Budapest towards Croatia and will also link the city of Pécs, the European Capital of Culture for 2010 to the network. A consortium consisting of the firms Strabag, Colas, John Laing and Intertoll were awarded a contract in autumn 2007 to design, build and operate a section with a length of 48 km. An important part of the works is the construction of the M6 tunnel chain consisting of four twin‐bore, two‐lane motorway tunnels. These tunnels were built by Strabag. During the driving of the longest tunnel, a collapse occurred in summer 2008, in which both tunnel bores caved in over a length of 200 m. The lecture reports on the driving of the tunnel through the collapsed area and the construction of the subsequent inner lining works, which made it possible to maintain the opening date.

In Ungarn wird ein Autobahnnetz sternförmig von Budapest aus errichtet. Die Autobahn M6 verläuft von Budapest Richtung Süden, somit Richtung Kroatien. Zusätzlich wird die Stadt Pecs, Kulturhauptstadt Europas 2010, an das Autobahnnetz angeschlossen. Ein Konsortium, bestehend aus den Firmen Strabag, Colas, John Laing und Intertoll, haben im Herbst 2007 den Auftrag erhalten, einen Abschnitt dieser Autobahn mit einer Länge von 48 km zu planen, zu errichten und zu betreiben. Ein wesentliches Teilstück dieses Auftrags ist Errichtung der Tunnelkette M6, bestehend aus vier zweiröhrigen zweispurigen Autobahntunneln. Diese Tunnel wurden von der Firma Strabag errichtet. Beim Vortrieb des längsten Tunnels kam es im Sommer 2008 zu einem Verbruch, bei dem beide Tunnelröhren auf einer Länge von 200 m einstürzten. Der Vortrag berichtet über die Auffahrung des Verbruchs und die Durchführung der folgenden Innenschalenarbeiten, die es ermöglichten, den Eröffnungstermin einzuhalten.
Large‐scale integration of microarray data reveals genes and pathways common to multiple cancer types
Authors: Dawany Noor B. , Dampier Will N. , Tozeren Aydin
Published: December 2010

The global gene expression analysis of cancer and healthy tissues typically results in large numbers of genes that are significantly altered in cancer. Such data, however, has been difficult to interpret due to the high level of variation of gene lists across laboratories and the small sample sizes used in individual studies. In this investigation, we compiled microarray data obtained from the same platform family from 84 laboratories, resulting in a database containing 1,043 healthy tissue samples and 4,900 cancer samples for 13 different tissue types. The primary cancers considered included adrenal gland, brain, breast, cervix, colon, kidney, liver, lung, ovary, pancreas, prostate and skin tissues. We normalized the data together and analyzed subsets for the discovery of genes involved in normal to cancer transformation. Our integrated significance analysis of microarrays approach produced top 400 gene lists for each of the 13 cancer types. These lists were highly statistically enriched with genes already associated with cancer in research publications excluding microarray studies (p < 1.31 E ‐ 12). The genes MTIM and RRM2 appeared in nine and TOP2A in eight lists of significantly altered genes in cancer. In total, there were 132 genes present in at least four gene lists, 11 of which were not previously associated with cancer. The list contains 17 metal ions and 15 adenyl ribonucleotide binding proteins, six kinases and six transcription factors. Our results point to the value of integrating microarray data in the study of combination drug therapies targeting metastasis.
Identifying strategies for increasing degree attainment in STEM: Lessons from minority‐serving institutions
Authors: Perna Laura W. , Gasman Marybeth , Gary Shannon , Lundy‐Wagner Valerie , Drezner Noah D.
Published: December 2010

Presented in this chapter is a case study of African American female STEM majors attending a historically Black women's college. We offer numerous implications for future research based on institutional characteristics that help explain women's achievement and high rates of STEM degree attainment.
An anti‐deficit achievement framework for research on students of color in STEM
Authors: Harper Shaun R.
Published: December 2010

A framework adapted from the National Black Male College Achievement Study is introduced in this chapter as a lens through which to explore the enablers of student achievement in STEM. The chapter places an emphasis on reframing deficit‐oriented research questions regarding students of color and their trajectories in STEM fields.
Undergraduate research participation and STEM graduate degree aspirations among students of color
Authors: Strayhorn Terrell L.
Published: December 2010

The importance of undergraduate research experiences and the extent to which engagement in such activities influences underrepresented minority students' graduate degree aspirations in science, technology, engineering, and mathematics fields is the focus of this chapter.
Biphasic effects of transforming growth factor β on bone morphogenetic protein–induced osteoblast differentiation
Authors: de Gorter David JJ , van Dinther Maarten , Korchynskyi Olexandr , ten Dijke Peter
Published: December 2010

Bone morphogenetic proteins (BMPs) exert an important role in skeletal development, adult bone homeostasis, and fracture healing and have demonstrated clinical utility for bone regeneration. However, BMPs fall short as regenerative agents because high doses need to be used to obtain therapeutic effects. Determining the molecular mechanisms controlling BMP-induced bone formation may lead to the development of more effective BMP-based therapies. To identify kinases mediating BMP-induced osteoblast differentiation, we performed an siRNA screen to find kinases modulating BMP-6-induced alkaline phosphatase (ALP) activity. Surprisingly, although transforming growth factor β (TGF-β) generally is considered to antagonize BMP-induced osteoblast differentiation, C2C12 cells transfected with siRNAs targeting TGF-β receptors displayed reduced BMP-6-induced ALP activity. Furthermore, pharmacologic inhibitors blocking the TGF-β type I receptor impaired BMP-induced ALP activity in KS483 and C2C12 cells and mineralization of KS483 cells. Consistently, costimulation with BMPs and TGF-β further increased expression of osteoblast-specific genes, ALP activity, and mineralization of KS483 cells and primary mesenchymal stem cells compared with BMPs alone. The stimulatory and inhibitory effects of TGF-β were found to depend on timing and duration of the costimulation. TGF-β inhibited BMP-induced activation of a BMP-Smad-dependent luciferase reporter, suggesting that the stimulatory effect of TGF-β is not due to increased BMP-Smad activity. TGF-β also inhibited the BMP-induced expression of the BMP antagonist noggin and prolonged BMP activity. In conclusion, TGF-β, besides acting as an inhibitor, also can, by dampening the noggin-mediated negative-feedback loop, enhance BMP-induced osteoblast differentiation, which might be beneficial in fracture healing. © 2011 American Society for Bone and Mineral Research.
Effect of native defects and Co doping on ferromagnetism in HfO2: First‐principles calculations
Authors: Han Chong , Yan Shi‐Shen , Lin Xue‐Ling , Hu Shu‐Jun , Zhao Ming‐Wen , Yao Xin‐Xin , Chen Yan‐Xue , Liu Guo‐Lei , Mei Liang‐Mo
Published: December 2010

First‐principles calculations of undoped HfO2 and cobalt‐doped HfO2 have been carried out to study the magnetic properties of the dielectric material. In contrast to previous reports, it was found that the native defects in HfO2 could not induce strong ferromagnetism. However, the cobalt substituting hafnium is the most stable defect under oxidation condition, and the ferromagnetic (FM) coupling between the cobalt substitutions is favorable in various configurations. We found that the FM coupling is mediated by the threefold‐coordinated oxygen atoms in monoclinic HfO2 and could be further enhanced in electron‐rich condition. © 2010 Wiley Periodicals, Inc. J Comput Chem, 2011
Rhyncophorus palmarum L. (Linnaeus, 1758): A morphological and histological study of the female reproductive system
Authors: Camargo Mathias Maria Izabel , Sánchez Pedro , Denardi Sandra Eloisi , Caetano Flávio Henrique
Published: December 2010

Rhyncophorus palmarum (Coleoptera) is a pest of great economic importance because of the damage caused in the plants of the Palmae family. This study showed that the female reproductive system of this beetle is composed of two ovaries of the telotrophic meroistic type invariably containing two ovarioles per ovary. Each ovariole is home to about 50 oocytes at different stages of maturation. The proximal region of the ovary is rather peculiar because it houses inside it a large quantity of bacilliform structures immersed in a glycolipoprotein substance, which has never before been described in the literature. The function of these structures is still unknown. However, it is suggested that they can function as a method of neutralizing the resistance of the plant because these insects are responsible for the transmission of the red ring disease to the palm plants. Microsc. Res. Tech., 2011. © 2010 Wiley‐Liss, Inc.
Morphology and lectin‐binding sites of pyloric caeca epithelium in normal and GnRH‐treated Atlantic bluefin tuna (Thunnus thynnus) Linnaeus 1758
Authors: Zizza Sara , Desantis Salvatore
Published: December 2010

Mucosal epithelium of pyloric caeca was studied in normal and in GnRH‐treated Atlantic bluefin tuna Thunnus thynnus L., using morphological analysis, conventional and lectin glycohistochemistry. The lining epithelium consisted of columnar (absorptive) cells, goblet cells and intraepithelial leucocytes. The epithelium from normal animals was significantly taller than GnRH‐treated samples. Conventional histochemistry displayed the same staining pattern in normal and hormone‐treated specimens which showed a mixture of neutral and sulphated acidic glycoconjugates in the luminal surface and goblet cells, and neutral glycans in apical granules of enterocytes. Lectin histochemistry revealed a different glycoconjugate pattern in normal and GnRH‐treated tunas. In normal specimens the luminal surface expressed sialoglycoconjugates which bound MAL II, SNA, KOH‐sialidase‐PNA, KOH‐sialidase‐SBA as well as asialoglycans stained with HPA, SBA, GSA I‐B4, LTA. N‐linked glycans were highlighted by Con A and KOH‐sialidase‐WGA. In GnRH‐treated tunas the luminal surface did not react with SNA, SBA and LTA. The columnar cells of normal tunas bound KOH‐sialisase‐PNA in the apical region, KOH‐sialidase‐PNA, KOH‐sialidase‐DBA, HPA, SBA, KOH‐sialidase‐SBA and KOH‐sialidase‐WGA in apical granules, GSA I‐B4 and LTA in the supranuclear region. GnRH‐treated specimens showed some columnar cells that stained with KOH‐sialidase‐WGA in the apical granules and with GSA I‐B4 in the supranuclear region. The goblet cells of normal animals produced mucins positive to PNA, HPA, KOH‐sialidase‐DBA, SBA, GSA II. The latter three binding sites lacked in GnRH‐treated tunas. The results suggest that the mucosal epithelium of Thunnus thynnus L. pyloric caeca expresses a complex glycan pattern that is affected by GnRH‐treatment. Microsc. Res. Tech., 2011. © 2010 Wiley‐Liss, Inc.
Synthesis and antimicrobial and pharmacological properties of new thiosemicarbazide and 1,2,4‐triazole derivatives
Authors: Popiołek Łukasz , Dobosz Maria , Chodkowska Anna , Jagiełło‐Wójtowicz Ewa , Kosikowska Urszula , Malm Anna , Mazur Liliana , Rzączyńska Zofia
Published: December 2010

Reaction of 4‐phenyl‐4H‐1,2,4‐triazole‐3‐thione with ethyl bromoacetate has led to the formation of ethyl [(4‐phenyl‐4H‐1,2,4‐triazol‐3‐yl)sulfanyl]acetate 1, the structure of which was confirmed by X‐ray analysis. In the next reaction with 80% hydrazide hydrate, appropriate hydrazide 2 was obtained, which in reaction with isothiocyanates was converted to new acyl derivatives of thiosemicarbazides 2, 3, 3a, 3b, 3c, 3d, 3e, 3f, 3g, 3h. The cyclization of these compounds in alkaline media has led to formation of new derivatives of 5‐{[(4‐phenyl‐4H‐1,2,4‐triazole‐3‐yl)sulfanyl]methyl}‐4H‐1,2,4‐triazole‐3(2H)‐thiones 4a, 4b, 4c, 4d, 4e, 4f, 4g, 4j. The structure of the compounds was confirmed by elementary analysis and IR, 1H‐NMR, 13C‐NMR, and MS spectra. Compounds 2, 3, 3a, 3b, 3c, 3d, 3e, 3f, 3g, 3h and 4a, 4b, 4c, 4d, 4e, 4f, 4g were screened for their antimicrobial activities, and the influence of the compounds 4a, 4b, and 4e, 4f, 4g on the central nervous system of mice in behavioral tests was examined. J. Heterocyclic Chem., (2011).
An efficient one‐pot synthesis of pyrazolo[3,4‐b]pyridinone derivatives catalyzed by L‐proline
Authors: Shi Chun‐Ling , Chen Hui , Shi Da‐Qing
Published: December 2010

A series of 3‐methyl‐1,4‐disubstituted‐4,5‐dihydro‐1H‐pyrazolo[3,4‐b]pyridine‐6(7H)‐ones was synthesized via the three‐component reaction of aldehyde, 3‐methyl‐1‐phenyl‐1H‐pyrazol‐5‐amine, and Meldrum's acid catalyzed by L‐proline. This protocol has the advantages of easier work‐up, milder reaction conditions, and high yields. J. Heterocyclic Chem., (2011).
Assessing patient perceptions of hospitalist communication skills using the Communication Assessment Tool (CAT)
Authors: Ferranti Darlene E. , Makoul Gregory , Forth Victoria E. , Rauworth Jennifer , Lee Jungwha , Williams Mark V.
Published: December 2010

BACKGROUND:

Hospitalists care for an increasing percentage of hospitalized patients, yet evaluations of patient perceptions of hospitalists' communication skills are lacking.

OBJECTIVE:

Assess hospitalist communication skills using the Communication Assessment Tool (CAT).

METHODS:

A cross‐sectional study of patients, age 18 or older, admitted to the hospital medicine service at an urban, academic medical center with 873 beds. Thirty‐five hospitalists assigned to both direct care and teaching service were assessed.

MEASUREMENTS:

Hospitalist communication was measured with the CAT. The 14‐item survey, written at a fourth grade level, measures responses along a 5‐point scale (“poor” to “excellent”). Scores are reported as a percentage of “excellent” responses.

RESULTS:

We analyzed 700 patient surveys (20 for each of 35 hospitalists). The proportion of excellent ratings for each hospitalist ranged from 38.5% to 73.5%, with an average of 59.1% excellent (SD=9.5). Highest ratings on individual CAT items were for treating the patient with respect, letting the patient talk without interruptions, and talking in terms the patient can understand. Lowest ratings were for involving the patient in decisions as much as he or she wanted, encouraging the patient to ask questions, and greeting the patient in a way that made him or her feel comfortable. Overall scale reliability was high (Cronbach's alpha = 0.97).

CONCLUSIONS:

The CAT can be used to gauge patient perceptions of hospitalist communication skills. Many hospitalists may benefit from targeted training to improve communication skills, particularly in the areas of encouraging questions and involving patients in decision making. Journal of Hospital Medicine 2010. © 2010 Society of Hospital Medicine.
What can we learn from patient dissatisfaction? An analysis of dissatisfying events at an academic medical center
Authors: Lee Alicia V. , Moriarty John P. , Borgstrom Christopher , Horwitz Leora I.
Published: December 2010

BACKGROUND:

Patient satisfaction is typically measured by quantitative surveys using predetermined domains. However, dissatisfaction may be an entity distinct from satisfaction, may have different determinants, and may better reflect problems in healthcare delivery.

OBJECTIVE:

The aim of this study was to describe domains of dissatisfaction experienced by patients during hospitalization.

SETTING:

The setting was a U.S. urban academic medical center.

PATIENTS:

The patients were adults discharged between July 1, 2007 and June 30, 2008

INTERVENTION:

The intervention was a postdischarge telephone interview: “If there was one thing we could have done to improve your experience in the hospital, what would it have been?”

MEASUREMENTS:

The measurements were standard qualitative analysis of suggestions for improvement.

RESULTS:

We randomly selected 976 of 9,764 interviews. A total of 439/976 (45.0%) included at least one suggestion for improvement. We identified six major domains of dissatisfaction: ineptitude (7.7%), disrespect (6.1%), waits (15.8%), ineffective communication (7.4%), lack of environmental control (15.6%), and substandard amenities (6.9%). These domains corresponded to six implicit expectations for quality hospital care: safety, treatment with respect and dignity, minimized wait times, effective communication, control over physical surroundings, and high‐quality amenities. Some of these expectations, such as for safe care, effective communication between providers, and lack of disrespect, may not be adequately captured in existing patient satisfaction assessments.

CONCLUSIONS:

The results represent patient‐generated priorities for quality improvement in healthcare. These priorities are not all consistently represented in standard patient satisfaction surveys and quality improvement initiatives. Patient input is critical to assessing the quality of hospital care and to identifying areas for improvement. Journal of Hospital Medicine 2010. © 2010 Society of Hospital Medicine.
The innovation necessity: Evidence from microcredit in the Dominican Republic
Authors: Bradley Steven W. , Artz Kendall , Hulett Jimmy
Published: December 2010

This study examines the role of business innovation as an important, but understudied intervening relationship between microcredit loans and income level. Using archival and survey data of microcredit clients from the Dominican Republic, the study finds that loan size has a positive effect on income level, but only in the presence of business innovation. We find that greater business training in relation to competitors is a significant indicator of business innovation. The findings also suggest that personal characteristics and competitive environment play a joint, but opposite role with innovation in predicting income level. Copyright © 2010 John Wiley & Sons, Ltd.
Microvascularization of the interhyoid muscle in larval Xenopus laevis (Daudin): Scanning electron microscopy of vascular corrosion casts and correlative light microscopy
Authors: Rattey J. , Lametschwandtner A.
Published: December 2010

The interhyoid muscle in tadpoles of Xenopus laevis (Daudin) is an important part of the buccal pump, a functional unit that provides unidirectional flow of water through mouth and pharynx. In anuran tadpoles, this flow is crucial in both respiration (gas exchange) and food intake (ingestion). The microvascular anatomy of the interhyoid muscles of 43 tadpoles of X. laevis from developmental stages 49–60 was examined by scanning electron microscopy of vascular corrosion casts and correlative light microscopy of paraplast embedded Goldner stained serial tissue sections. Analysis of vascular corrosion casts of the interhyoid muscle showed that several descending branches of external carotid arteries supplied the interhyoid muscle. Arteries splitted into many arterioles at the dorsal surface of the interhyoid muscle and formed sheaths of longitudinally orientated capillaries around muscle fibers. Postcapillary vessels formed perpendicularly orientated arrays of collecting venules (mean diameter: 15.6 μm), which drained the interhyoid muscle from the ventral surface into external jugular veins. Cast analyses revealed sprouting angiogenesis at the capillary level and nonsprouting angiogenesis at distal domains of the venous system. Both means of angiogenesis that persisted throughout the developmental periods examined are thought to represent a superposition of concurrent developmental and physiological processes. The dense microvascular bed of the interhyoid muscle reflects its high demand for supply with oxygen and nutrients. J. Morphol., 2011. © 2010 Wiley‐Liss, Inc.
Towards the development of a corrosion map for Abu Dhabi
Authors: Ganther W. D. , Cole I. S. , Helal A. M. , Chan W. , Paterson D. A. , Trinidad G. , Corrigan P. , Mohamed R. , Sabah N. , Al‐Mazrouei A.
Published: December 2010

Infrastructure development in the United Arab Emirates continues to escalate, yet very few corrosion studies have been performed in the region. In a step to address this situation, this paper reports on a study of zinc and steel corrosion and salt deposition rates at five sites in the Emirate of Abu Dhabi. The sites are classified as either urban/marine, marine, inland or mountainous. The study found that zinc corrosion rates range from 15 µm/year on the coast to 0.6 µm/year inland, while steel corrosion rates are 56 and 10 µm/year, respectively, at the same locations. While the salt deposition rate ranges from 5 to 18 mg/m2/day, it is not directly related to distance from the coast. Although the salt deposition rates observed are consistent with those at locations at similar latitudes, the corrosion rates are higher than in locations with comparable salt deposition rates. However, when the data were analysed along with relevant local meteorological data, it was found to be consistent with the basic assumptions of the holistic model of atmospheric corrosion developed byColeet al. In particular, it is suggested that the relatively high corrosion rates observed here are associated with a greater accumulation of salt, which can occur in Abu Dhabi because rainfall, and thus rain washing, is extremely low compared to similar exposure locations in Australia and South‐East Asia.
Preparation of Optically Active Nanoparticles by Emulsification of Preformed Helical Polymers
Authors: Zhang Yuanyuan , Luo Xiaofeng , Deng Jianping , Yang Wantai
Published: December 2010

The preparation of nanoparticles consisting of chiral helical substituted polyacetylenes via emulsification of the preformed polymers is reported. Two types of helically substituted acetylenes were examined as model polymers: two chiral poly(N‐propargylamide)s and two achiral poly(N‐propargylamide)s. The four polymers were emulsified with SDS as emulsifier to form nanoparticles. The particle size can be modulated by varying the SDS concentration. A comparison between nanoparticle emulsion and the corresponding polymer solution demonstrated obvious blue shifts in the CD spectra of nanoparticle emulsions made from helical polymers with relatively not‐so‐bulky pendent groups, for which the possible mechanism was proposed.

magnified image
Imaging lung microstructure in mice with hyperpolarized 3He diffusion MRI
Authors: Wang Wei , Nguyen Nguyet M. , Yablonskiy Dmitriy A. , Sukstanskii Alexander L. , Osmanagic Emir , Atkinson Jeffrey J. , Conradi Mark S. , Woods Jason C.
Published: December 2010

Quantitative measurement of lung microstructure is of great significance in assessment of pulmonary disease, particularly in the earliest stages. The technique for MRI‐based 3He lung morphometry was previously developed and validated for human lungs, and was recently extended to ex vivo mouse lungs. The technique yields accurate, quantitative information about the microstructure and geometry of acinar airways. In this study, the 3He lung morphometry technique is successfully implemented for in vivo studies of mice. Results indicate excellent agreement between in vivo morphometry via 3He MRI and microscopic morphometry after sacrifice. This opens up new avenues for application of the technique as a precise, noninvasive, in vivo biomarker of changes in lung microstructure, within various mouse models of lung disease. Magn Reson Med, 2011. © 2010 Wiley‐Liss, Inc.
Novel 16‐channel receive coil array for accelerated upper airway MRI at 3 Tesla
Authors: Kim Yoon‐Chul , Hayes Cecil E. , Narayanan Shrikanth S. , Nayak Krishna S.
Published: December 2010

Upper airway MRI can provide a noninvasive assessment of speech and swallowing disorders and sleep apnea. Recent work has demonstrated the value of high‐resolution three‐dimensional imaging and dynamic two‐dimensional imaging and the importance of further improvements in spatio‐temporal resolution. The purpose of the study was to describe a novel 16‐channel 3 Tesla receive coil that is highly sensitive to the human upper airway and investigate the performance of accelerated upper airway MRI with the coil. In three‐dimensional imaging of the upper airway during static posture, 6‐fold acceleration is demonstrated using parallel imaging, potentially leading to capturing a whole three‐dimensional vocal tract with 1.25 mm isotropic resolution within 9 sec of sustained sound production. Midsagittal spiral parallel imaging of vocal tract dynamics during natural speech production is demonstrated with 2 × 2 mm2 in‐plane spatial and 84 ms temporal resolution. Magn Reson Med, 2011. © 2010 Wiley‐Liss, Inc.
Iron quantification of microbleeds in postmortem brain
Authors: McAuley Grant , Schrag Matthew , Barnes Samuel , Obenaus Andre , Dickson April , Holshouser Barbara , Kirsch Wolff
Published: December 2010

Brain microbleeds (BMB) are associated with chronic and acute cerebrovascular disease and present a source of pathologic iron to the brain proportional to extravasated blood. Therefore, BMB iron content is potentially a valuable biomarker. We tested noninvasive phase image methods to quantify iron content and estimate true source diameter (i.e., unobscured by the blooming effect) of BMB in postmortem human tissue. Tissue slices containing BMB were imaged using a susceptibility weighted imaging protocol at 11.7T. BMB lesions were assayed for iron content using atomic absorption spectrometry. Measurements of geometric features in phase images were related to lesion iron content and source diameter using a mathematical model. BMB diameter was estimated by image feature geometry alone without explicit relation to the magnetic susceptibility. A strong linear relationship (R2 = 0.984, P < 0.001) predicted by theory was observed in the experimental data, presenting a tentative standardization curve where BMB iron content in similar tissues could be calculated. In addition, we report BMB iron mass measurements, as well as upper bound diameter and lower bound iron concentration estimates. Our methods potentially allows the calculation of brain iron load indices based on BMB iron content and classification of BMB by size unobscured by the blooming effect. Magn Reson Med, 2011. © 2010 Wiley‐Liss, Inc.
Enhancing toughness of low‐density polyethylene filaments through infusion of multiwalled carbon nanotubes and ultrahigh molecular weight polyethylene
Authors: Khan Mujibur R. , Mahfuz Hassan , Leventouri Theodora , Rangari Vijaya K. , Kyriacou Andreas
Published: December 2010

We report enhancement in fracture strain and toughness of low‐density polyethylene by infusing multiwalled carbon nanotubes (MWCNT) and a second‐phase polymer; ultrahigh molecular weight polyethylene (UHMWPE). Infusion of MWCNT improved strength and modulus by about 23 and 57%, respectively, but reduced fracture strain (∼45%) and toughness (∼36%). UHMWPE was then dispersed as a minor phase, and the resulting nanocomposites showed a 55% increase in toughness without any loss of strength or modulus. The loading of MWCNT and UHMWPE was 2 and 8% by weight, respectively. Nanocomposites were in the form of filaments and were extruded through a melt extrusion process. Differential scanning calorimetry and X‐ray diffraction studies revealed increase in crystallinity and crystallite size. Scanning electron microscope micrographs showed sliding of polymer interfaces and changes in fracture process. Strain hardening experiments also showed improvement in strength and modulus but reduction in toughness. POLYM. ENG. SCI., 2011. © 2010 Society of Plastics Engineers.
Synthesis of amphiphilic polyacetal by polycondensation of aldehyde and polyethylene glycol as an acid‐labile polymer for controlled release of aldehyde
Authors: Wang Yanmei , Morinaga Hisatoyo , Sudo Atsushi , Endo Takeshi
Published: December 2010

A new acid‐labile polymer having acetal moieties in the main chain was synthesized by polycondensation of poly (ethylene glycol) (PEG) and lilial, an aldehyde widely used in fragrance applications. The hydrophobicity of the resulting acetal moiety and the hydrophilicity of the PEG chain allowed the polyacetal to exhibit amphiphilicity. The polyacetal derived from PEG having weight average molecular weight (Mw) of 1000 (PEG1000) was soluble in water and self‐associated to form associates in water. The polyacetals were hydrolyzed in acidic aqueous solutions to release hydrophobic lilial from the systems. The release rate of aldehyde from the polyacetal derived from PEG1000 was higher than that from the polyacetal derived from PEG having Mw of 400 (PEG400). These results supported that the release rate of lilial can be controlled by the chain length of PEG, on which hydrophilicity of polyacetal depends. © 2010 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem, 2011
Poly(ε‐caprolactone)‐based shape memory polymers with variable polydimethylsiloxane soft segment lengths
Authors: Zhang Dawei , Giese Melissa L. , Prukop Stacy L. , Grunlan Melissa A.
Published: December 2010

Thermoresponsive shape memory polymers (SMPs) are stimuli‐responsive materials that return to their permanent shape from a temporary shape in response to heating. The design of new SMPs which obtain a broader range of properties including mechanical behavior is critical to realize their potential in biomedical as well as industrial and aerospace applications. To tailor the properties of SMPs, “AB networks” comprised of two distinct polymer components have been investigated but are overwhelmingly limited to those in which both components are organic. In this work, we prepared inorganic‐organic SMPs comprised of inorganic polydimethylsiloxane (PDMS) segments of varying lengths and organic poly(ε‐caprolactone) (PCL) segments. PDMS has a particularly low Tg (−125 °C) which makes it a particularly effective soft segment to tailor the mechanical properties of PCL‐based SMPs. The SMPs were prepared via the rapid photocure of solutions of diacrylated PCL40‐block‐PDMSm‐block‐PCL40 macromers (m = 20, 37, 66, and 130). The resulting inorganic‐organic SMP networks exhibited excellent shape fixity and recovery. By changing the PDMS segment length, the thermal, mechanical, and surface properties were systematically altered. © 2010 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem, 2011
Influence of Argon and Nitrogen Admixture in HMDSO/O2 Plasmas onto Powder Formation
Authors: Ricci Marina , Dorier Jean‐Luc , Hollenstein Christoph , Fayet Pierre
Published: December 2010

In situ Fourier transform infrared spectroscopy was used to study the powder formation of hexamethyldisiloxane/O2 plasmas. The spectra show that oxygen plays an important role at the beginning of the process. A large amount of oxygen is responsible for intense powder formation. The admixture of inert or non‐reactant gases, such as Ar or N2, into the plasma promotes polymerization of the monomer. The formation of the particulates, the evolution of their size, and chemical characteristics give evidence of a multistep growth process. The size, as well as the production rate, undergoes a reduction once the Ar or N2 amount is increased in the plasma admixture.

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Atmospheric Pressure Plasma Technology: a Straightforward Deposition of Antibacterial Coatings
Authors: Sarghini S. , Paulussen S. , Terryn H.
Published: December 2010

Bacterial adhesion and proliferation is a widespread problem following an increasing trend. In this paper, antibacterial coatings were deposited on stainless steel substrates by means of atmospheric pressure plasma technology. Butylamine and 3‐(trimethoxysilyl)‐propyldimethyoctadecylammonium chloride (ODAMO) were used as precursors. The influence of the plasma parameters was investigated by variation of the power input levels and operation under different carrier gases. Characterization of the coating was carried out using contact angle measurement, atomic force microscopy (AFM), field emission scanning electron microscopy (FE‐SEM), and X‐ray photoelectron spectroscopy (XPS). Carrier gas change affected the chemical composition and the surface energy of ODAMO based coating. Moreover, bactericidal activity is decreasing with increase of the plasma power input. Hydrophilic and smooth ODAMO based plasma coating presented the best antibacterial performance. Deposited layers demonstrated up to a log 6 reduction against E. coli after 24 h incubation. Butylamine‐based plasma coatings presented a limited antibacterial effect and the influence of the plasma parameters was not detected.

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Complex networks as a unified framework for descriptive analysis and predictive modeling in climate science
Authors: Steinhaeuser Karsten , Chawla Nitesh V. , Ganguly Auroop R.
Published: December 2010

The analysis of climate data has relied heavily on hypothesis‐driven statistical methods, while projections of future climate are based primarily on physics‐based computational models. However, in recent years a wealth of new datasets has become available. Therefore, we take a more data‐centric approach and propose a unified framework for studying climate, with an aim toward characterizing observed phenomena as well as discovering new knowledge in climate science. Specifically, we posit that complex networks are well suited for both descriptive analysis and predictive modeling tasks. We show that the structural properties of ‘climate networks’ have useful interpretation within the domain. Further, we extract clusters from these networks and demonstrate their predictive power as climate indices. Our experimental results establish that the network clusters are statistically significantly better predictors than clusters derived using a more traditional clustering approach. Using complex networks as data representation thus enables the unique opportunity for descriptive and predictive modeling to inform each other. © 2011 Wiley Periodicals, Inc. Statistical Analysis and Data Mining 4: 497–511, 2011
Characterization of the TRIP/TWIP effect in austenitic stainless steels using Stress‐Temperature‐Transformation (STT) and Deformation‐Temperature‐Transformation (DTT) Diagrams
Authors: Kovalev A. , Jahn A. , Weiß A. , Scheller P. R.
Published: December 2010

Stress‐Temperature‐Transformation (STT) and Deformation‐Temperature‐Transformation (DTT) diagrams are suitable to characterize the TRIP (transformation‐induced plasticity) and TWIP (twinning‐induced plasticity) effect in steels. The triggering stresses for the deformation‐induced microstructure transformation processes, the characteristic temperatures, the yield stress and the strength of the steel are plotted in the STT diagram as functions of temperature. The elongation values of the austenite, the strain‐induced twins and martensite formations are shown on the DTT diagram.

The systematics of STT and DTT diagrams and the method for their development are described. Especially, the correlations between the STT and DTT diagrams and the thermodynamics are explained in the present paper. The developed STT and DTT diagrams for a novel austenitic Cr‐Mn‐Ni (16%Cr, 6% Mn, 6% Ni) as‐cast steel and austenitic steel AISI 304 are presented. The Cr‐Mn‐Ni steel shows a deformation‐induced α′‐martensite and twin formation. In contrast, the AISI 304 shows a deformation‐induced ε‐ and α′‐martensite formation. The differences between both steel grades are based on thermodynamic pre‐conditions.

Therefore the thermodynamic stability conditions of the phases and the kinetics of stress and deformation‐induced martensite and the twins formation are reflected in the developed STT and DTT diagrams.
Strategically planning to change
Authors: Atkins Kemal
Published: December 2010

Strategic planning can be a powerful instrument in bringing about lasting change to a student affairs organization. Tools and methods to achieve transformation are discussed.
Data‐driven planning: Using assessment in strategic planning
Authors: Bresciani Marilee J.
Published: December 2010

Adopting the practice of systematically and strategically gathering data to inform the development and implementation of a strategic plan will ensure its achievement. This chapter presents a combination of techniques for student affairs professionals to conduct data‐driven planning.
An active role for splicing in 3′‐end formation
Authors: Martinson Harold G.
Published: December 2010

When intron‐defined splicing was replaced by exon‐defined splicing in the evolution of higher eukaryotes, the splicing apparatus had to rely on the cleavage/polyadenylation (CP) apparatus for help in defining the 3′‐terminal exon. The 3′‐terminal exon‐definition complex that resulted consists of splicing factors on the upstream 3′ splice site (ss) interacting with CP factors on the downstream poly(A) signal. A speculative model for assembly of this processing complex proposes several discrete steps. First, the splicing factor, U2AF65, interacts with the CP factor, CFIm. Then, CFIm is displaced from U2AF65 by the poly(A) polymerase during a remodeling step. Finally, the U2 snRNP interacts with CPSF in a step resembling spliceosomal A‐complex formation. The result is mutual enhancement of both splicing and CP for the exon. In contrast, when the poly(A) signal is preceded by a 5′ rather than a 3′ ss, competition replaces cooperation. Thus, a poly(A) site in an intron must compete with the upstream 5′ ss for pairing with the 3′ ss further upstream, across the presumptive exon. If the poly(A) site wins the competition, a terminal exon is defined. But if the 5′ ss wins (by defining the upstream exon as internal, followed by pairing with a 3′ ss across the downstream intron), then the poly(A) site is suppressed. The U1 snRNP obviously participates in this competition through its role in splice site pairing. However, the U1 snRNP can also bind elsewhere in the transcript, apart from splice sites, to regulate CP by direct interaction with the CP factors. WIREs RNA 2011 2 459–470 DOI: 10.1002/wrna.68

This article is categorized under:

RNA Processing > 3' End Processing
Analysis of a pre‐stressed bi‐material accelerated‐life‐test (ALT) specimen
Authors: Suhir E.
Published: December 2010

Application of mechanical pre‐stressing could be an effective means for achieving a failure‐mode‐shift‐free “destructive ALT effect” in electronic and photonic devices and micro‐electro‐mechanical systems (MEMS). A simple, physically meaningful and easy‐to‐use analytical (“mathematical”) predictive model has been developed to assess the magnitude and the distribution of stresses in a bi‐material assembly subjected to the combined action of thermally induced (considered by the ALT design) and external (“mechanical”) pre‐stressing. Such a compressive pre‐stressing is applied to the assembly component that is expected to experience thermal compression. The model is an extension and a modification of the author's 1986 and 1989 “bi‐metal thermostat” models suggested as a generalization of the 1925 Timoshenko's theory.
Formalizing a hierarchical file system
Authors: Hesselink Wim H. , Lali Muhammad Ikram
Published: December 2010

An abstract file system is defined here as a partial function from (absolute) paths to data. Such a file system determines the set of valid paths. It allows the file system to be read and written at a valid path, and it allows the system to be modified by the Unix operations for creation, removal, and moving of files and directories. We present abstract definitions (axioms) for these operations. This specification is refined towards a pointer implementation. The challenge is to have a natural abstraction function from the implementation to the specification, to define operations on the concrete store that behave exactly in the same way as the corresponding functions on the abstract store, and to prove these facts. To mitigate the problems attached to partial functions, we do this in two steps: first a refinement towards a pointer implementation with total functions, followed by one that allows partial functions. These two refinements are proved correct by means of a number of invariants. Indeed, the insights gained consist, on the one hand, of the invariants of the pointer implementation that are needed for the refinement functions, and on the other hand of the precise enabling conditions of the operations on the different levels of abstraction. Each of the three specification levels is enriched with a permission system for reading, writing, or executing, and the refinement relations between these permission systems are explored. Files and directories are distinguished from the outset, but this rarely affects our part of the specifications. All results have been verified with the proof assistant PVS, in particular, that the invariants are preserved by the operations, and that, where the invariants hold, the operations commute with the refinement functions.