bluuebunny/crossref_metadata_2025 huggingface dataset:
Multiple Sclerosis and Risk of Infection-Related Hospitalization and Death in US Veterans
Authors: Nelson Richard E. , Xie Yan , DuVall Scott L. , Butler Jorie , Kamauu Aaron W. C. , Knippenberg Kristin , Schuerch Markus , Foskett Nadia , LaFleur Joanne
Published: February 2015

Background: This study estimated the risk of infection-related hospitalizations and death in patients with and without multiple sclerosis (MS).

Methods: We identified adults with MS in the US Department of Veterans Affairs (VA) system between 1999 and 2010. Each veteran with MS was matched, on age and sex, with up to four veterans without MS. Multivariable Cox proportional hazards regression models were performed to assess the influence of MS on the development of serious and fatal infections.

Results: The cohort included 7743 veterans with MS and 30,972 veterans without MS. Mean (SD) age was 53.8 (13.3) years, and 80.8% were male. The incidence per 1000 person-years of overall serious infections was 19.2 (95% confidence interval [CI], 17.6–20.8) for those with MS and 10.3 (95% CI, 9.8–10.9) for those without MS. Fatal infection incidence rates were 1.2 (95% CI, 0.8–1.7) for patients with MS and 0.5 (95% CI, 0.3–0.6) for patients without MS. Regression models showed that veterans with MS were at greater risk for overall serious (hazard ratio [HR] = 1.52, P < .01) and fatal (HR = 1.85, P = .03) infections and serious respiratory (HR = 1.31, P = .01), urinary tract (HR = 4.44, P < .01), and sepsis-related infections (HR = 2.56, P < .01).

Conclusions: This study provides evidence that VA patients with MS are more likely than those without MS to be hospitalized and die of infection.
Plasma Exchange in a Patient with Tumefactive, Corticosteroid-Resistant Multiple Sclerosis
Authors: Ikeda Kristin M. , Lee Donald H. , Fraser J. Alexander , Mirsattari Seyed , Morrow Sarah A.
Published: February 2015

Tumefactive multiple sclerosis (MS) is an aggressive form of MS that can be difficult to treat with standard therapies. In severe MS relapses, plasma exchange (PLEX) has shown some benefit, but reports of its use in patients with tumefactive MS are limited. This article describes the successful use of PLEX in a patient with tumefactive MS. A 46-year-old right-handed woman with a recent diagnosis of MS presented with drowsiness, dysarthria, horizontal nystagmus, and quadriparesis. Her brain magnetic resonance images demonstrated multiple tumefactive demyelinating lesions in the medulla, bilateral periventricular white matter, and corona radiata white matter. She was initially treated with a 10-day course of intravenous methylprednisolone without benefit; therefore, PLEX was initiated. After the second exchange, the patient started to improve and was discharged initially to rehabilitation and then home. She was started on disease-modifying therapy with natalizumab and did not experience further relapses but had slow clinical decline during the next year, which led to discontinuation of natalizumab treatment. PLEX may be used as second-line treatment in corticosteroid-resistant MS relapses, but there are limited reports of its use in patients with tumefactive MS. This patient presented with aggressive disease with multiple tumefactive lesions and did not respond to standard treatment with corticosteroids. PLEX was successful in improving her symptoms, allowing her to return home, although the disease progressed during the next year.
Lidocaine-Induced Methemoglobinemia: A Clinical Reminder
Authors: Barash Mark , Reich Keith A. , Rademaker Dennis
Published: February 2015

Methemoglobinemia is a rare condition in which the iron in hemoglobin is stabilized in the ferric (Fe3+) form, making it unable to bind oxygen and leading to tissue hypoxia and possibly death. The condition may be hereditary or acquired, the latter resulting from ingestion or application of common oxidizing agents such as lidocaine. As management of methemoglobinemia depends on prompt recognition, clinicians who administer or prescribe oxidizing agents must be aware of the clinical symptoms of methemoglobinemia, including cyanosis, pulse oximetry values that do not respond to increased oxygen delivery, and altered mental status. Currently, methylene blue is the drug of choice for the management of methemoglobinemia.
Resolution of Dacryostenosis After Osteopathic Manipulative Treatment
Authors: Apoznanski Theresa E. , Abu-Sbaih Reem , Terzella Michael J. , Yao Sheldon
Published: February 2015

Dacryostenosis is an obstruction of the nasolacrimal duct and is the most common cause of epiphora and ocular discharge in newborns. Whereas most cases resolve spontaneously, invasive treatment may become necessary if symptoms persist past age 6 to 12 months. In the present case, a 9-month-old boy with persistent dacryostenosis was scheduled for lacrimal duct probing after first-line treatments failed. After a single session of osteopathic manipulative treatment, the patient's epiphora and other symptoms resolved, and he no longer needed surgical probing. A review of the literature highlights key pathophysiologic processes, management options, and musculoskeletal aspects of dacryostenosis. Physicians should consider osteopathic manipulative treatment in the management of dacryostenosis.
κ‐distributed protons in the solar wind and their charge‐exchange coupling to energetic hydrogen
Authors: Heerikhuisen J. , Zirnstein Eric , Pogorelov Nikolai
Published: February 2015

The interaction between the solar wind and the interstellar medium represents a collision between two plasma flows, resulting in a heliosphere with an extended tail. While the solar wind is mostly ionized material from the corona, the interstellar medium is only partially ionized. The ion and neutral populations are coupled through charge‐exchange collisions that operate on length scales of tens to hundreds of astronomical units. About half the interstellar hydrogen flows into the heliosphere where it may charge‐exchange with solar wind protons. This process gives rise to a nonthermal proton, known as a pickup ion, which joins the plasma. In this paper we investigate the effects of approximating the total ion distribution of the subsonic solar wind as a generalized Lorentzian, or κ distribution, using an MHD neutral code. We illustrate the effect different values of the κ parameter have on both the structure of the heliosphere and the energetic neutral atom flux at 1 AU. We find that using a κ distribution in our simulations yields levels of energetic neutral atom flux that are within a factor of about 2 or 3 over the IBEX‐Hi range of energies from 0.5 to 6 keV. While the presence of a suprathermal tail in the proton distribution leads to the production of high‐energy neutrals, the sharp decline in the charge‐exchange cross section around 10 keV mitigates the enhanced transfer of energy from the ions to the neutrals that might otherwise be expected.
Vertical structure of cumulonimbus towers and intense convective clouds over the South Asian region during the summer monsoon season
Authors: Bhat G. S. , Kumar Shailendra
Published: February 2015

The vertical structure of radar reflectivity factor in active convective clouds that form during the South Asian monsoon season is reported using the 2A25 version 6 data product derived from the precipitation radar measurements on board the Tropical Rainfall Measuring Mission satellite. We define two types of convective cells, namely, cumulonimbus towers (CbTs) and intense convective cells (ICCs). CbT is defined referring to a reflectivity threshold of 20 dBZ at 12 km altitude and is at least 9 km thick. ICCs are constructed referring to reflectivity thresholds at 8 km and 3 km altitudes. Cloud properties reported here are based on 10 year climatology. It is observed that the frequency of occurrence of CbTs is highest over the foothills of Himalayas, plains of northern India and Bangladesh, and minimum over the Arabian Sea and equatorial Indian Ocean west of 90°E. The regional differences depend on the reference height selected, namely, small in the case of CbTs and prominent in 6–13 km height range for ICCs. Land cells are more intense than the oceanic ones for convective cells defined using the reflectivity threshold at 3 km, whereas land versus ocean contrasts are not observed in the case of CbTs. Compared to cumulonimbus clouds elsewhere in the tropics, the South Asian counterparts have higher reflectivity values above 11 km altitude.
Unerwartetes Lumineszenzverhalten von Münzmetall‐π‐Diboren‐Komplexen
Authors: Bissinger Philipp , Steffen Andreas , Vargas Alfredo , Dewhurst Rian D. , Damme Alexander , Braunschweig Holger
Published: February 2015

Eine Reihe von beispiellosen photophysikalischen Phänomenen konnten bei Studien an lumineszierenden π‐Diboren‐Komplexen von Cu und Ag beobachtet werden, unter anderem für Komplexe dieser Metalle ungewöhnlich hohe Fluoreszenz‐Quantenausbeuten in Lösung (bis zu 100 %). Dies deutet auf wenig bis kein Intersystem‐Crossing zwischen S1 und Tn in den Komplexen hin, trotz der starken Spin‐Bahn‐Kopplung der Metallatome. Die Substitution des Kohlenstoffs durch Bor führt damit zu lumineszierenden Isolobalanaloga von ansonsten nicht emittierenden Olefin‐Komplexen des Cu und Ag.
Elektronentransfer in Peptiden: Bildung von Silbernanopartikeln
Authors: Kracht Sonja , Messerer Matthias , Lang Matthieu , Eckhardt Sonja , Lauz Miriam , Grobéty Bernard , Fromm Katharina M. , Giese Bernd
Published: February 2015

Einige Mikroorganismen zeigen anaerobe mineralische Respiration, bei der sie Metallionen zu Metallnanopartikeln reduzieren. Hierbei werden Peptide als Medium für den Elektronentransfer (ET) verwendet. Diese Reaktionsklasse wird anhand eines Modellpeptids und Silber als Metall diskutiert. Erstaunlicherweise können Silberionen, die von Peptiden mit Histidin als silberbindender Aminosäure und Tyrosin als photoinduziertem Elektronendonor gebunden sind, nicht unter ET‐Bedingungen zu Ag‐Nanopartikeln (AgNPs) reduziert werden, weil das Peptid die Aggregation von Ag‐Atomen zu AgNPs verhindert. Nur in Gegenwart von Chloridionen, die zur Bildung von AgCl‐Mikrokristallen führen, entstehen AgNPs. Diese Reaktion beginnt mit der Bildung von 100 nm großen Ag@AgCl‐Peptid‐Nanokompositen, die dann in 15 nm große AgNPs aufgebrochen werden. Diese kontrollierte Umwandlung von großen in kleinere Nanopartikeln kann detailliert in zeitaufgelösten UV/Vis‐Spektren untersucht werden.
The Fluorenyl Cation
Authors: Costa Paolo , Trosien Iris , Fernandez‐Oliva Miguel , Sanchez‐Garcia Elsa , Sander Wolfram
Published: February 2015

The fluorenyl cation is a textbook example for a 4π antiaromatic cation. However, contrasting results have been published on how the annelated benzene rings compensate the destabilizing effect of the 4π antiaromatic five‐membered ring in its core. Whereas previous attempts to synthesize this cation in superacidic media resulted in undefined polymeric material only, we herein report that it can be generated and isolated in amorphous water ice at temperatures below 30 K by photolysis of diazofluorene. Under these conditions, the fluorenylidene is protonated by water to give the fluorenyl cation, which could be characterized spectroscopically. Its absorption in the visible‐light range matches that previously obtained by ultrafast absorption spectroscopy, and furthermore, its IR spectrum could be recorded. The IR bands in amorphous ice very nicely match predictions from DFT and DFT/MM calculations, suggesting the absence of strong interactions between the cation and surrounding water molecules.
O2‐vermittelte dehydrierende Aminierung von Phenolen
Authors: Louillat‐Habermeyer Marie‐Laure , Jin Rongwei , Patureau Frederic W.
Published: February 2015

Eine Methode zur direkten dehydrierenden Bildung von C‐N‐Bindungen zwischen ungeschützten Phenolen und einer Reihe von cyclischen Anilinen wurde entwickelt, die ohne Metallaktivierung oder den Einsatz von Halogenidverbindungen auskommt. Stattdessen genügt eine rein organische Aktivierung von molekularem Sauerstoff mit anschließender Oxidation der Anilinsubstrate. Diese können mit zahlreichen Phenolen gekuppelt werden, wodurch eine atomökonomische dehydrierende Aminierungsmethode zur Synthese von Aminophenolen zur Verfügung steht. Diese neuartige Reaktivität, die als ein modifizierter Hock‐Aktiverungsprozess von Sauerstoff angesehen werden kann, beruht auf der intrinsischen organischen Reaktivität von Cumol und dürfte wichtige Auswirkungen für die Bildung von C‐N‐Bindungen haben.
Yttrium Complexes of Arsine, Arsenide, and Arsinidene Ligands
Authors: Pugh Thomas , Kerridge Andrew , Layfield Richard A.
Published: February 2015

Deprotonation of the yttrium–arsine complex [Cp′3Y{As(H)2Mes}] (1) (Cp′=η5‐C5H4Me, Mes=mesityl) by nBuLi produces the μ‐arsenide complex [{Cp′2Y[μ‐As(H)Mes]}3] (2). Deprotonation of the AsH bonds in 2 by nBuLi produces [Li(thf)4]2[{Cp′2Y(μ3‐AsMes)}3Li], [Li(thf)4]2[3], in which the dianion 3 contains the first example of an arsinidene ligand in rare‐earth metal chemistry. The molecular structures of the arsine, arsenide, and arsinidene complexes are described, and the yttrium–arsenic bonding is analyzed by density functional theory.
Site‐Specific Solid‐State NMR Studies of “Trigger Factor” in Complex with the Large Ribosomal Subunit 50S
Authors: Barbet‐Massin Emeline , Huang Chih‐Ting , Daebel Venita , Hsu Shang‐Te Danny , Reif Bernd
Published: February 2015

Co‐translational protein folding is not yet well understood despite the availability of high‐resolution ribosome crystal structures. We present first solid‐state NMR data on non‐mobile regions of a prokaryotic ribosomal complex. Localized chemical shift perturbations and line broadening are observed for the backbone amide resonances corresponding to the regions in the trigger factor ribosome‐binding domain that are involved in direct contact with the ribosome or undergo conformational changes upon ribosome binding. This large asymmetric protein complex (1.4 MDa) becomes accessible for NMR investigations by the combined use of proton detection and high MAS frequencies (60 kHz). The presented results open new perspectives for the understanding of the mechanism of large molecular machineries.
Formation of Thin Films of Organic–Inorganic Perovskites for High‐Efficiency Solar Cells
Authors: Stranks Samuel D. , Nayak Pabitra K. , Zhang Wei , Stergiopoulos Thomas , Snaith Henry J.
Published: February 2015

Organic–inorganic perovskites are currently one of the hottest topics in photovoltaic (PV) research, with power conversion efficiencies (PCEs) of cells on a laboratory scale already competing with those of established thin‐film PV technologies. Most enhancements have been achieved by improving the quality of the perovskite films, suggesting that the optimization of film formation and crystallization is of paramount importance for further advances. Here, we review the various techniques for film formation and the role of the solvents and precursors in the processes. We address the role chloride ions play in film formation of mixed‐halide perovskites, which is an outstanding question in the field. We highlight the material properties that are essential for high‐efficiency operation of solar cells, and identify how further improved morphologies might be achieved.
Catalytic Asymmetric Hydroalkenylation of Vinylarenes: Electronic Effects of Substrates and Chiral N‐Heterocyclic Carbene Ligands
Authors: Ho Chun‐Yu , Chan Chun‐Wa , He Lisi
Published: February 2015

An asymmetric tail‐to‐tail cross‐hydroalkenylation of vinylarenes with terminal olefins was achieved by catalysis with NiH complexes bearing chiral N‐heterocyclic carbenes (NHCs). The reaction provides branched gem‐disubstituted olefins with high enantioselectivity (up to 94 % ee) and chemoselectivity (cross/homo product ratio: up to 99:1). Electronic effects of the substituents on the vinylarenes and on the N‐aryl groups of the NHC ligands, but not a π,π‐stacking mechanism, assist the steric effect and influence the outcome of the cross‐hydroalkenylation.
O2‐mediated dehydrogenative amination of phenols
Authors: Louillat‐Habermeyer Marie‐Laure , Jin Rongwei , Patureau Frederic W.
Published: February 2015

A method was developed for the direct dehydrogenative construction of CN bonds between unprotected phenols and a series of cyclic anilines without resorting to any kind of metal activation of either substrate and without the use of halides. The resulting process relies on the exclusively organic activation of molecular oxygen and the subsequent oxidation of the aniline substrate. This allows the coupling of ubiquitous phenols, thus furnishing aminophenols through an atom‐economical and most sustainable dehydrogenative amination method. This new reactivity, which relies on the intrinsic organic reactivity of cumene in what can be seen as a modified Hock activation process of oxygen, is expected to have a large impact on the formation of CN bonds in organic synthesis.
Model Predictive Control for Discrete‐Time Systems with Random Delay and Randomly Occurring Nonlinearity
Authors: Shi Yujing , Li Shanqiang , Wu Junfeng , Chen Dongyan
Published: February 2015

In this paper, the model predictive control problem is investigated for a class of discrete‐time systems with random delay and randomly occurring nonlinearity. The randomly occurring nonlinearity, which describes the phenomena of a class of nonlinear disturbances occurring in a random way, is modeled according to a Bernoulli distributed white sequence with a known conditional probability. Moreover, the random delay is governed by a discrete‐time finite‐state Markov chain. The approach of delay fractioning is applied to the controller synthesis. It is shown that the proposed model predictive controller guarantees the stochastic stability of the closed‐loop system. Finally, a numerical simulation is given to illustrate the effectiveness of the proposed method.
Hygrothermisches Verhalten teilgedämmter und teilbeschatteter Flachdachkonstruktionen aus Holz
Authors: Nusser Bernd , Bachinger Julia , Teibinger Martin
Published: February 2015

Bei Industrie‐ und Gewerbebauten sind große Spannweiten mit Trägerhöhen von > 50 cm nicht ungewöhnlich. Aufgrund wirtschaftlicher Gesichtspunkte werden solch hohe Gefache zumeist nicht voll ausgedämmt. Unter Bauphysikern werden teilgedämmte und durch Attiken, Dachaufbauten oder benachbarte Gebäude teilbeschattete Flachdachkonstruktionen bisher kritisch bewertet. Die Holzforschung Austria (HFA) untersuchte anhand von Freiland‐ und Laborversuchen das hygrothermische Verhalten von solchen teilgedämmten und teilbeschatteten Flachdachkonstruktionen aus Holz. Hierbei wurde neben dem Dämmgrad (Teildämmung/Volldämmung) auch die Orientierung der Elemente (Pfetten‐/Sparrenelement) variiert. Die Untersuchungsergebnisse zeigen, dass es bei vollgedämmten Elementen im beschatteten Bereich zu deutlich geringeren Temperaturen und zu höheren Luft‐ und Materialfeuchten kommt als bei teilgedämmten Elementen. Bei einer Teilbeschattung sind die Klimabedingungen in den vollgedämmten Elementen deutlich inhomogener als in den teilgedämmten Elementen, was auf die verstärkte Luftumwälzung im dämmstofffreien Bereich zurückzuführen ist. Dieser ausgleichende Effekt zwischen besonntem und beschatteten Bereich ist bereits bei einem Luftspalt von 5 cm Höhe zu beobachten.

Hygrothermal behaviour of partly insulated and partly shaded wooden flat roofs. Roof constructions of commercial and industrial buildings are often formed by wooden flat roofs with large beam spans. Thus, rafters with heights over 50 cm are common. Because of economic considerations such high cavities are usually not fully insulated. Moreover, these partly insulated roofs are mostly partly shaded by parapets, technical installations or adjacent buildings. Such partly insulated and partly shaded flat roofs are critically evaluated by building physicists. The present study reveals the hygrothermal behaviour of such partly insulated and partly shaded wooden flat roofs, based on long term field and laboratory experiments carried out at the Holzforschung Austria (HFA). In addition to the level of insulation (partly insulated/fully insulated) the orientation of the elements (lengthwise to eave/at the right angle to eave) is varied. The measurements show significantly lower temperatures and higher moisture content in the cavity in the shaded area of fully insulated roof elements compared to partly insulated elements. The climate conditions in the cavity in the fully insulated roof elements are much more inhomogeneous compared to the partly insulated ones. The potential air circulation in the air layer above the insulation generates this balancing effect. Already an air layer with 5 cm height leads to more favourable conditions in the partly shaded area.
Radonmessungen in Wohngebäuden im Rybniker Kreis
Authors: Wysocka Małgorzata , Rubin Jan Antoni
Published: February 2015

Im Artikel werden die Ergebnisse der Radonkonzentrationsuntersuchungen in Wohngebäuden in Rybnik/Polen und Umgebung beschrieben. Bei den Messungen, die in einigen Kampagnen in den Jahren 2005 bis 2009 durchgeführt wurden, wurde die passive Messmethode angewandt und die Spurdetektoren der Alpha‐Teilchen genutzt. Es wurden 122 Messungen in den Kellerräumen und jeweils im Erdgeschoss in 59 Gebäuden vorgenommen. Die Expositionszeit der Detektoren betrug 2 bis 6 Monate. Der Bereich der gemessenen Radonkonzentrationen betrug von 10 ± 10 bis 390 ± 40 Bq/m³ im Erdgeschoss und von 20 ± 10 bis 740 ± 50 Bq/m³ in den Kellerräumen. Arithmetische Mittelwerte der Messungen betrugen entsprechend 80 Bq/m3 im Erdgeschoss sowie 138 Bq/m3 in den Kellerräumen und waren höher als die Mittelwerte, die für das gesamte Gebiet Polens und für das Schlesische Kohlerevier (GZW) berechnet wurden.

Radon measurements in dwellings in Rybnik Borough. In this paper a results of radon measurements in dwellings in the area of Rybnik city (Southern Poland, Upper Silesia) and its vicinity are presented. Measurements have been performed within several campaigns in the period 2005 to 2009. For this purpose solid state nuclear track detector (SSNTD) were applied, a passive method for measurements of radon gas concentration. The total number of measurements was 122 in basements and ground floor dwellings of 59 buildings. The exposure time of the detectors varied from 2 to 6 months. The range of measured radon concentrations was within 10 ± 10 to 390 ± 40 Bq/m3 at the ground floor level and from 20 ± 10 to 740 ± 50 Bq/m3 in the basements. The average values of measured concentration were as follows: 80 Bq/m3 for ground floor dwellings and 138 Bq/m3 for basements. These values are higher than the average values for Poland as well as for the Upper Silesian Coal Basin (USCB).
Harmonisierung der Berechnungsverfahren der axialen Tragfähigkeit für offene Profile nach EA‐Pfähle und EAU
Authors: Lüking Jan , Becker Patrick
Published: February 2015

Die axiale Tragfähigkeit von offenen Profilen (Stahlrohrpfähle und einfache oder doppelte Stahlträgerprofile) kann nach den Empfehlungen der EA‐Pfähle oder EAU auf der Grundlage von Erfahrungswerten berechnet werden. Vergleichend angewendet führen diese Verfahren jedoch zu unterschiedlichen Ergebnissen, die in der Bemessung Unsicherheiten beim Anwender zur Folge haben. Dieser Aufsatz harmonisiert beide Berechnungsverfahren miteinander. Hierzu werden, basierend auf einer Datenbank mit dynamischen und statischen Pfahlprobebelastungsergebnissen, mit statistischen Methoden neue Erfahrungswerte zur Tragfähigkeitsberechnung abgeleitet. Hierbei wird die Pfropfenbildung über einen vereinfachten Berechnungsansatz in Abhängigkeit des Pfahldurchmessers berücksichtigt. Aufgrund der großen Datenmenge kann dieses Verfahren als näherungsweise abgesichert angesehen werden und wird für beide Regelwerke zur Anwendung empfohlen. Eine Parameterstudie und Vergleichsberechnungen runden den Beitrag ab.

Harmonization of axial capacity calculation for open‐ended piles according to EA‐Pfähle and EAU

The axial pile resistance of open ended piles like open ended pipe piles, H‐piles and double H‐piles can be calculated after the recommendations of EA‐Pfähle or EAU. A comparison of these calculation methods shows that the results differ from each other. This can cause uncertainties to the users which are following the recommendations. The paper harmonizes both calculation methods. Based on a database with dynamic and static pile resistance results, new empirical values for the calculation of bearing capacity are derived using statistical methods. Furthermore the soil plugging effect is considered in a simplified method depending on the pile diameter. The validation of the new calculation method with statistic methods is based on the amount of pile tests in the database and can be confirmed. Therefore, this method is suggested for application in both national recommendations. This paper closes with a parameter study and comparison calculations.
Optimierungspotenzial für thermisch aktivierte Gründungspfähle (Energiepfähle)
Authors: Kuhlmann Jan , Oldorf Björn , Kühl Jens‐Uwe
Published: February 2015

Die Nutzung oberflächennaher Geothermie ermöglicht eine wirtschaftliche und umweltschonende Bereitstellung regenerativ gewonnener thermischer Energie als Alternative zu einer konventionellen Wärme‐ bzw. Kälteversorgung. Als geothermisches Quellensystem werden zunehmend sogenannte “thermoaktive erdberührte Bauteile” wie z. B. Gründungspfähle oder Bodenplatten verwendet. Deren unter baustatischen Gesichtspunkten erfolgende Herstellung bietet noch deutliches Optimierungspotenzial für die Nutzung als Erdwärmeübertrager.

Im Rahmen des europäischen Forschungsprojektes “e‐hub” sind daher rechnergestützte Modellierungsarbeiten zur Untersuchung von Möglichkeiten für die Erhöhung der Leistungsfähigkeit von thermisch aktivierten Gründungspfählen, sogenannten Energiepfählen, durchgeführt worden.

Dabei zeigte sich insbesondere bei der Verwendung von gut wärmeleitenden Zuschlagstoffen für den Pfahlbeton eine Steigerung der thermischen Leistungsfähigkeit der Energiepfähle von bis zu ca. 30 %, verglichen mit regulärem Pfahlbeton. Je nach Projektumfang und konstruktiver Pfahlausführung kann durch dessen Verwendung eine deutliche Verbesserung der Energieeffizienz und damit eine nachhaltige Wirtschaftlichkeit des Geothermieprojektes bei moderat erhöhten Herstellungskosten erreicht werden.

Potential for optimization of thermally activated foundation piles (energy piles) – A modelling approach from the EU‐funded research project “e‐hub”

The use of shallow geothermal energy enables a cost‐effective and environmentally friendly provision of renewable thermal energy as an alternative to conventional heating and cooling supply. As a geothermal source system, so called “thermally activated construction parts” such as foundation piles or floor plates, are being used increasingly often. Those are designed mainly for structural purposes and hence offer significant optimization potential for the use as a geothermal heat exchanger.

Therefore computational modeling works have been carried out as part of the European research project “e‐hub”. Their major aim was to investigate options for a performance increase of thermally activated foundation piles, so‐called “energy piles”.

A particularly evident performance increase of up to 30 % could be demonstrated for the use of highly thermally conductive aggregates in pile concrete compared with regular concrete. Depending on the actual project scope and the constructive pile design, a significant improvement in energy efficiency and sustainable profitability of real world geothermal projects are expected at moderately increased production costs
Systematische Brückenerhaltung – eine fachübergreifende Herausforderung
Authors: Holst Ralph
Published: February 2015

Der Wirtschaftsstandort Deutschland benötigt eine leistungsfähige und zuverlässige Straßeninfrastruktur. Brücken können sehr schnell zu einem Engpass werden, wenn ungeplant Verkehrseinschränkungen bis hin zu Sperrungen vorgenommen werden müssen. In der Vergangenheit wurde dieser möglichen Situation nicht immer ausreichend Rechnung getragen und somit ist es an der Zeit, einer systematischen Brückenerhaltung mehr Bedeutung beizumessen. Die Gründe für den aktuellen Zustand der Brücken sind so vielfältig wie die Brücken selbst. Da spielen Planungs‐ und Ausführungsfehler eine Rolle sowie die Tatsache, dass die Verkehre deutlich stärker zugenommen haben als in allen Prognosen der Vergangenheit vorausgesagt. Da es sich bei Brücken fast immer um Unikate handelt, die sich sehr unterschiedlich verhalten, ist das Spektrum der notwendigen Erfassungs‐ und Bewertungsmöglichkeiten und der daraus resultierenden Erhaltungsmaßnahmen sehr vielfältig. So besteht die Herausforderung in der Zukunft darin, dieser Vielfältigkeit angemessen Rechnung zu tragen, um die Brücken möglichst nachhaltig zu erhalten. Die unterschiedlichen Werkzeuge dafür existieren, werden erarbeitet bzw. fortgeschrieben. Jetzt gilt es, diese Möglichkeiten systematisch einzusehen, damit es mit möglichst geringem Aufwand gelingt, für den gesamten Brückenbestand die geeigneten Erhaltungsmaßnahmen zu planen und umzusetzen und dabei die Nutzung – im Vorfeld und während der Erhaltungsmaßnahmen – möglichst wenig zu beeinträchtigen.

Systematic maintenance of Bridges – a multidisciplinary challenge

The business location Germany requires an efficient and reliable road infrastructure. Bridges can become a bottleneck when unplanned traffic restrictions to the point of closures can occur. In the past this possible situation wasn't considered sufficiently and thus it is to attach more importance to systematic bridge maintenance. The reasons for the current state of the bridges are as varied as the bridges themselves. Planning and execution errors play a role, but also the fact that traffic has increased significantly more than any forecast of the past have predicted is very important. Bridges are normally unique and therefore they behave very differently. So the spectrum of the necessary collection and assessment options and the resulting maintenance measures are very diverse. Thus, the challenge in the future is to address this diversity appropriately in order to obtain the bridges as sustainable as possible. The different tools exist for it, shall be developed and updated. Now it's time to use these facilities systematically, to find the most suitable maintenance measures for the entire bridge inventory with the least possible effort and the least possible interferences of the traffic before and during the maintenance actions.
Die semiintegrale Grubentalbrücke – Besonderheiten bei der Bauausführung
Authors: Keil Andreas , Wenger Philipp
Published: February 2015

Mit der Fertigstellung der Grubentalbrücke im Abschnitt 8.1 des Verkehrsprojekts VDE 8 wurde im Sommer 2013, am Hochpunkt des Streckenabschnitts Ebensfeld–Erfurt, ein weiterer Lückenschluss auf der Neubaustrecke Nürnberg–Erfurt–Halle/Leipzig–Berlin (VDE 8) vollbracht. Die Grubentalbrücke gehört zu einer Reihe von besonderen Bauwerken des Neubauprojekts, die in einer neuen, in semiintegraler, Bauart errichtet wurden. Über die konstruktionsbedingten Besonderheiten dieser Bauart wurde bereits in der Bautechnik in Heft 10/2011 berichtet [1], hier mit dem Fokus auf die planerischen Besonderheiten und Anforderungen semiintegraler Brücken. Der vorliegende Beitrag soll nun die Besonderheiten bei der Bauausführung näher beleuchten. Dies beinhaltet einerseits Anforderungen an den Bauablauf und die Bautechnologie, bedingt durch die semiintegrale Bauweise, wie beispielsweise das ‘Einstellen von Biegemomenten’ im Zuge des Baufortschritts. Andererseits sollen auch allgemeingültige Sachverhalte bei der Ausführung einer Spannbetonbrücke Erwähnung finden, denen jedoch bei der Ausführung einer integralen bzw. semiintegralen Talbrücke eine besondere Bedeutung zukommt.

The semi‐integral Grubental‐Bridge – specific challenges during construction

With the completion of the Grubental‐Bridge in summer 2013, within the sector 8.1 of the German major infrastructure project VDE8, situated at the up‐station of the track‐section Ebensfeld–Erfurt, yet another closure of the new high‐speed line Nuremberg–Erfurt–Halle/Leipzig–Berlin was achieved. The Grubental‐Bridge is among a series of special bridges, which were build based on a new construction method, as integral or semi‐integral bridges. In the journal Bautechnik 10/2011 [1] the specifics of the integral construction method were already described, focusing on the design‐related specifics and challenges. Following up, the report at hand shall highlight selected specific challenges during the construction of the bridge. It reflects specific requirements for the construction and equipment, connected to the semi‐integral design, such as the ‘adjusting of bending stresses’ in the course of construction, for instance. Beyond that some general issues in connection with the construction of a pre‐stressed concrete bridge shall be introduced, which however become more important in the case of a integral or semi‐integral bridge, as for instance the geometric control during the erection process.
Directed Divergent Evolution of a Thermostable D‐Tagatose Epimerase towards Improved Activity for Two Hexose Substrates
Authors: Bosshart Andreas , Hee Chee Seng , Bechtold Matthias , Schirmer Tilman , Panke Sven
Published: February 2015

Functional promiscuity of enzymes can often be harnessed as the starting point for the directed evolution of novel biocatalysts. Here we describe the divergent morphing of an engineered thermostable variant (Var8) of a promiscuous D‐tagatose epimerase (DTE) into two efficient catalysts for the C3 epimerization of D‐fructose to D‐psicose and of L‐sorbose to L‐tagatose. Iterative single‐site randomization and screening of 48 residues in the first and second shells around the substrate‐binding site of Var8 yielded the eight‐site mutant IDF8 (ninefold improved kcat for the epimerization of D‐fructose) and the six‐site mutant ILS6 (14‐fold improved epimerization of L‐sorbose), compared to Var8. Structure analysis of IDF8 revealed a charged patch at the entrance of its active site; this presumably facilitates entry of the polar substrate. The improvement in catalytic activity of variant ILS6 is thought to relate to subtle changes in the hydration of the bound substrate. The structures can now be used to select additional sites for further directed evolution of the ketohexose epimerase.
Characterization of FabG and FabI of the Streptomyces coelicolor Dissociated Fatty Acid Synthase
Authors: Singh Renu , Reynolds Kevin A.
Published: February 2015

Streptomyces coelicolor produces fatty acids for both primary metabolism and for biosynthesis of the secondary metabolite undecylprodiginine. The first and last reductive steps during the chain elongation cycle of fatty acid biosynthesis are catalyzed by FabG and FabI. The S. coelicolor genome sequence has one fabI gene (SCO1814) and three likely fabG genes (SCO1815, SCO1345, and SCO1846). We report the expression, purification, and characterization of the corresponding gene products. Kinetic analyses revealed that all three FabGs and FabI are capable of utilizing both straight and branched‐chain β‐ketoacyl‐NAC and enoyl‐NAC substrates, respectively. Furthermore, only SCO1345 differentiates between ACPs from both biosynthetic pathways. The data presented provide the first experimental evidence that SCO1815, SCO1346, and SCO1814 have the catalytic capability to process intermediates in both fatty acid and undecylprodiginine biosynthesis.
Structural and Functional Implications of the Interaction between Macrolide Antibiotics and Bile Acids
Authors: Glanzer Simon , Pulido Sergio A. , Tutz Sarah , Wagner Gabriel E. , Kriechbaum Manfred , Gubensäk Nina , Trifunovic Jovana , Dorn Markus , Fabian Walter M. F. , Novak Predrag , Reidl Joachim , Zangger Klaus
Published: February 2015

Macrolide antibiotics, such as azithromycin and erythromycin, are in widespread use for the treatment of bacterial infections. Macrolides are taken up and excreted mainly by bile. Additionally, they have been implicated in biliary system diseases and to modify the excretion of other drugs through bile. Despite mounting evidence for the interplay between macrolide antibiotics and bile acids, the molecular details of this interaction remain unknown. Herein, we show by NMR measurements that macrolides directly bind to bile acid micelles. The topology of this interaction has been determined by solvent paramagnetic relaxation enhancements (solvent PREs). The macrolides were found to be bound close to the surface of the micelle. Increasing hydrophobicity of both the macrolide and the bile acid strengthen this interaction. Both bile acid and macrolide molecules show similar solvent PREs across their whole structures, indicating that there are no preferred orientations of them in the bile micelle aggregates. The binding to bile aggregates does not impede macrolide antibiotics from targeting bacteria. In fact, the toxicity of azithromycin towards enterotoxicE. coli(ETEC) is even slightly increased in the presence of bile, as was shown by effective concentration (EC50) values.
ChemInform Abstract: The ′Sub′ Metallide Oxide Hydrides Sr21Si2O5H12+x and Ba21M2O5H12+x (M: Zn, Cd, Hg, In, Tl Si, Ge, Sn, Pb, As, Sb, Bi).
Authors: Jehle Michael , Hoffmann Anke , Kohlmann Holger , Scherer Harald , Roehr Caroline
Published: February 2015

The title compounds are synthesized from melts of composition A:M:O:H = 21:2:5:24 (A: Sr, Ba; M: Zn, Cd, Hg, In, Tl Si, Ge, Sn, Pb, As, Sb, Bi) using BaH2/SrH2 as hydrogen sources.
ChemInform Abstract: High‐Pressure Transformation in the Cobalt Spinel Ferrites.
Authors: Blasco J. , Subias G. , Garcia J. , Popescu C. , Cuartero V.
Published: February 2015

Pressure‐induced structural changes in CoxFe3‐xO4 (x = 1, 1.5, 1.75) spinels are characterized by high‐pressure angle‐dispersive XRD measurements at room temperature up to 34 GPa.
ChemInform Abstract: A Noble‐Metal‐Free, Tetra‐Nickel Polyoxotungstate Catalyst for Efficient Photocatalytic Hydrogen Evolution.
Authors: Lv Hongjin , Guo Weiwei , Wu Kaifeng , Chen Zheyuan , Bacsa John , Musaev Djamaladdin G. , Geletii Yurii V. , Lauinger Sarah M. , Lian Tianquan , Hill Craig L.
Published: February 2015

Na6K4 [Ni4(H2O)2 (PW9O34)2]·32H2O is synthesized by refluxing an aqueous solution of Na2WO4, Na2HPO4, and Ni(OAc)2 for 2.5 h, followed by addition of KOAc (73% yield).
ChemInform Abstract: Crystal Growth, Structure and Magnetic Properties of Sm3Ni5Al19: A Compound in the Sm2n+mNi4n+mAl15n+4m Homologous Series.
Authors: Subbarao Udumula , Ghosh Aloke Kumar , Sarkar Sumanta , Peter Sebastian C.
Published: February 2015

Large rod shaped single crystals of Sm3Ni5Al19 are prepared by the aluminium flux technique from mixtures of Sm, Ni, and Al (alumina crucible, 1000 °C for 5 h and 800 °C for 48 h, 70% yield).
ChemInform Abstract: Broensted Acidic Ionic Liquids of Aza‐Crown Ether Complex Cations: Preparation and Applications in Organic Reactions.
Authors: Cheng Chen , Jing Huanwang
Published: February 2015

Novel Broensted acidic ionic liquids composed of an aza‐crown ether chelated potassium cation and various anions are synthesized and completely characterized.
ChemInform Abstract: New Chiral Diphosphoramidite Rhodium(I) Complexes for Asymmetric Hydrogenation.
Authors: Drommi Dario , Micalizzi Giuseppe , Arena Carmela Grazia
Published: February 2015

Chiral Rh(I) complexes containing (R,R)‐1,2‐diaminocyclohexane as the backbone and two atropisomeric biaryl units are synthesized and successfully applied as catalysts in the asymmetric hydrogenation of functionalized olefins.
ChemInform Abstract: Sidearm as a Control in the Asymmetric Ring Opening Reaction of Donor—Acceptor Cyclopropane.
Authors: Kang Qikai , Wang Lijia , Zheng Zhongbo , Li Junfang , Tang Yong
Published: February 2015

Trisoxazoline and bisthiazoline based ligands with a chiral backbone on the sidearm and without chiral motif on the parent skeleton efficiently promote the amine nucleophilic ring opening reaction of 1,1‐cyclopropane diesters to γ‐amino acid derivatives.
ChemInform Abstract: Synthesis of Chiral α‐Benzyl‐β2‐hydroxy Carboxylic Acids Through Iridium‐Catalyzed Asymmetric Hydrogenation of α‐Oxymethylcinnamic Acids.
Authors: Li Ze‐Yu , Song Song , Zhu Shou‐Fei , Guo Na , Wang Li‐Xin , Zhou Qi‐Lin
Published: February 2015

The title compounds (II) are obtained by asymmetric hydrogenation of α‐oxymethylcinnamic acids using chiral spiro phosphine‐oxazoline/iridium complexes as catalysts.
ChemInform Abstract: Nucleophilic Ring‐Opening of Benzoxazinones by DBU: Some Observations.
Authors: Baravkar Sachin B. , Roy Arup , Gawade Rupesh L. , Puranik Vedavati G. , Sanjayan Gangadhar J.
Published: February 2015

The formation of an unusual product (V) during the coupling reaction of benzoxazinone and amino acids, mediated by DBU is reported.
ChemInform Abstract: Light‐Driven Organocatalysis using Inexpensive, Nontoxic Bi2O3 as the Photocatalyst.
Authors: Riente Paola , Matas Adams Alba , Albero Josep , Palomares Emilio , Pericas Miquel A.
Published: February 2015

The direct asymmetric alkylation of aldehydes (II) with α‐bromocarbonyl compounds is achieved in the presence of the combination of photocatalytic Bi2O3 and a chiral oxazolidinone catalyst.
ChemInform Abstract: NaBH3CN: A Janus Substitute for Tin‐Free Radical‐Based Reactions.
Authors: Guiard Julie , Rahali Yaniss , Praly Jean‐Pierre
Published: February 2015

Thermal radical reactions (reduction, Giese reaction) are studied on halosugars and α‐bromoamides.
ChemInform Abstract: t‐BuXPhos: A Highly Efficient Ligand for Buchwald—Hartwig Coupling in Water.
Authors: Wagner Patrick , Bollenbach Maud , Doebelin Christelle , Bihel Frederic , Bourguignon Jean‐Jacques , Salome Christophe , Schmitt Martine
Published: February 2015

The combination of t‐BuXPhos with [(cinnamyl)PdCl]2 shows high activity for coupling of aryl halides (II) with a large set of amines, amides, ureas, and carbamates.
ChemInform Abstract: Dehydrative Cross‐Coupling Reactions of Allylic Alcohols with Olefins.
Authors: Gumrukcu Yasemin , de Bruin Bas , Reek Joost N. H.
Published: February 2015

In the reactions with aliphatic allylic alcohols formation of regioisomeric products can be observed due to isomerization of the π‐allyl intermediate followed by β‐hydrogen elimination.
ChemInform Abstract: Chitosan: An Efficient Recyclable Catalyst for Transamidation of Carboxamides with Amines under Neat Conditions.
Authors: Nageswara Rao Sadu , Chandra Mohan Darapaneni , Adimurthy Subbarayappa
Published: February 2015

A series of amide derivatives (I) and (IV) as well as more challenging aryl and alkyl amines (VII) with long‐chain alkyl substituents are selectively converted into the corresponding transamidation products (III), (VI) and (IX), which are frequently found in biologically active compounds.
ChemInform Abstract: Expeditious Metal‐Free Access to Functionalized Polycyclic Acetals under Mild Aqueous Conditions.
Authors: Kasare Sanghratna , Bankar Siddheshwar K. , Ramasastry S. S. V.
Published: February 2015

Acetoxypyranones (I) and (VIII) undergo cascade Michael addition and cycloacetalization to afford furopyrans.
ChemInform Abstract: Ruthenium‐Catalyzed Oxidative Transformations of Terminal Alkynes to Ketenes by Using Tethered Sulfoxides: Access to β‐Lactams and Cyclobutanones.
Authors: Wang Youliang , Zheng Zhitong , Zhang Liming
Published: February 2015

Ru vinylidenes generated in situ from alkynes are oxidized to ketene intermediates by the tethered sulfoxide.
ChemInform Abstract: Economical and Efficient Aqueous Reductions of High Melting‐Point Imines and Nitroarenes to Amines: Promotion Effects of Granular PTFE.
Authors: Li Tao , Cui Xiaoxue , Sun Lili , Li Chunbao
Published: February 2015

The reduction of aromatic imines or aromatic nitro compounds by Zn powder can be performed in aqueous solution using catalytic amounts of Aliquat 336 in the presence of granular polytetrafluoroethylene and NaOH or NH4Cl.
ChemInform Abstract: One‐Pot Route to β‐Adrenergic Blockers via Enantioselective Organocatalyzed Epoxidation of Terminal Alkenes as a Key Step.
Authors: Held Felix E. , Wei Shengwei , Eder Kathrin , Tsogoeva Svetlana B.
Published: February 2015

A convenient two‐step one‐pot process leads to β‐blockers (R)‐pronethalol (IVa), nifenalol (IVb), and dichloroisoproterenol (IVc) from the corresponding aryl alkenes by combination of Shi‐epoxidation and aminolysis.
ChemInform Abstract: The Development of a Novel HAuCl4@MOF Catalyst and Its Catalytic Application in the Formation of Dihydrochalcones.
Authors: Luan Yi , Qi Yue , Yu Jie , Gao Hongyi , Schaus Scott E.
Published: February 2015

The catalyst is recycled and reused in four additional cycles without loss of activity.
ChemInform Abstract: Highly Efficient Dynamic Kinetic Resolution of Secondary Aromatic Alcohols at Low Temperature Using a Low‐Cost Sulfonated Sepiolite as Racemization Catalyst.
Authors: Wu Jian‐Ping , Meng Xiao , Wang Liang , Xu Gang , Yang Li‐Rong
Published: February 2015

The title reaction gives the products in high yields with high enantioselectivities.
ChemInform Abstract: Ethenolate Transfer Reactions: A Facile Synthesis of Vinyl Esters.
Authors: Kaliyaperumal Appaye Srinivasan , Pandurang Nikumbh Satish , Reddy Govindapur Rajeshwar , Banerjee Shyamapada , Bhalerao Dinesh S. , Syam Kumar Unniaran K.
Published: February 2015

A simple and efficient metal‐free ethenolate transfer reaction furnishing vinyl acetates (III) is developed.
ChemInform Abstract: A Novel Transition Metal‐Free Conjugate Reduction of α,β‐Unsaturated Ketones with Tosylhydrazine as a Hydrogen Source.
Authors: Zhou Xiaomeng , Li Xiaokang , Zhang Wei , Chen Junmin
Published: February 2015

The title novel and efficient method is a cheap, easy‐to‐handle, and convenient alternative to traditional catalytic hydrogenation.
ChemInform Abstract: Primary‐Tertiary Diamine/Broensted Acid Catalyzed α‐Allylation of Carbonyl Compounds with Allylic Alcohols.
Authors: Cui Lingyun , Zhang Long , Luo Sanzhong , Cheng Jin‐Pei
Published: February 2015

N,N‐Dimethylethylenediamine·TfOH is found to be an efficient catalyst for the direct α‐allylic alkylation of unmodified aldehydes with allylic alcohols.
ChemInform Abstract: Highly Selective Palladium‐Catalyzed Cross‐Coupling of Secondary Alkylzinc Reagents with Heteroaryl Halides.
Authors: Yang Yang , Niedermann Katrin , Han Chong , Buchwald Stephen L.
Published: February 2015

A general Pd‐based catalytic system is developed to allow the cross‐coupling of a broad spectrum of hetaryl halides with secondary Grignard reagents.
ChemInform Abstract: Prins Spirocyclization for the Synthesis of Spiro[isobenzofuran‐pyran] Derivatives.
Authors: Reddy B. V. Subba , Kumar Harish , Reddy P. Sivaramakrishna , Singarapu Kiran Kumar
Published: February 2015

This novel Prins spirocyclization gives a variety of the title compounds with high diastereoselectivities.
ChemInform Abstract: Selective Reductive Coupling of Nitro Compounds with Aldehydes to Nitrones in H2 Using Carbon‐Supported and ‐Decorated Platinum Nanoparticles.
Authors: Cisneros Larisha , Serna Pedro , Corma Avelino
Published: February 2015

Compared to common supported metal catalysts the Pt‐C‐catalyst shows a high selectivity for nitrone synthesis.
ChemInform Abstract: Design, Synthesis, and Biological Evaluation of Indolylidinepyrazolones as Potential Antibacterial Agents.
Authors: Indrasena A. , Riyaz Sd. , Mallipeddi Prema L. , Padmaja P. , Sridhar B. , Dubey P. K.
Published: February 2015

For example, knoevenagel condensation of indole‐3‐carbaldehyde with pyrazolone (II) provides coupling product (III) which shows antibacterial activity (MIC value 50 μg/ml).
ChemInform Abstract: Lewis Acid Catalyzed [3 + 2] Coupling of Indoles with Quinone Monoacetals or Quinone Imine Ketal.
Authors: Shu Chang , Liao Li‐Hua , Liao Yi‐Jun , Hu Xiao‐Yan , Zhang Yong‐Hong , Yuan Wei‐Cheng , Zhang Xiao‐Mei
Published: February 2015

A mild and concise [3 + 2] coupling of indoles and quinone monoacetals or quinone imine ketal promoted by a Lewis acid is developed.
ChemInform Abstract: Substituted Benzo[a]carbazoles and Indoleacetic Acids from Arylglyoxals and Enamines Through Domino Condensation, Thermal Cyclization, and Aromatization.
Authors: Maity Subhendu , Pathak Sudipta , Pramanik Animesh
Published: February 2015

The condensation of enamine (I), arylglyoxals, and malonitrile provide pyrrole derivatives (IV).