bluuebunny/crossref_metadata_2025 huggingface dataset:
In Plattenebene beanspruchte Biegeträger aus Brettsperrholz
Authors: Flaig Marcus
Published: November 2015

Für Brettsperrholzträger mit angeschnittenen Rändern werden Abminderungsfaktoren anhand der in Eurocode 5 für Brettschichtholzträger angegebenen Gleichungen hergeleitet. Für die zur Berechnung der Abminderungsfaktoren erforderlichen Festigkeitskennwerte der Brettsperrholzträger werden Gleichungen in Abhängigkeit des Lagenaufbaus und unter Berücksichtigung der möglichen Versagensmechanismen definiert. Für Brettsperrholzträger mit Durchbrüchen oder Ausklinkungen am Trägerauflager werden spannungsbasierte Bemessungsansätze beschrieben. Zur Berechnung der rechtwinklig zur Trägerlängsachse wirkenden Beanspruchungen werden die im deutschen Nationalen Anhang zu Eurocode 5 angegebenen Gleichungen für Brettschichtholzträger mit verstärkten Durchbrüchen und Ausklinkungen verwendet. Zur Berechnung von Spannungsspitzen im Bereich der Durchbrüche und Ausklinkungen werden mithilfe von Finite‐Elemente‐(FE)‐Berechnungen ermittelte Faktoren angegeben.

CLT beams loaded in plane direction – Part 2: Tapered CLT beams and CLT beams with holes or notches

Based on Eurocode 5 equations for the calculation of strength reduction factors for glulam beams, a method to determine the bending strength of CLT beams with tapered edges is presented. The strength properties of CLT beams needed as input values are defined in dependence of the beam layup taking into account possible failure modes. For CLT beams with holes or notches stress based design approaches are introduced. For the calculation of stresses perpendicular to the beam axis existing approaches given in the German National Annex to Eurocode 5 for reinforced glulam beams with holes or notches are used. Stress concentration factors determined by means of finite element method are introduced.
Ultraschalluntersuchungen an statisch beanspruchten Betonproben
Authors: von der Haar Christoph , Marx Steffen , Krompholz Rolf
Published: November 2015

Ultraschallmessverfahren bieten bereits heute in verschiedenen Wissenschaftsdisziplinen (z. B. Medizin, Biologie) ein enormes Leistungspotenzial. Aber auch in anderen bauaffinen Bereichen (z. B. Stahlbau, Natursteinprüfung) oder im Bereich der Geowissenschaften wird die Ultraschallmesstechnik erfolgreich und vielfach eingesetzt. Demgegenüber ist die Anwendung im Betonbau deutlich unterentwickelt, aber gerade in Laborversuchen zeigt das Verfahren, dass es zur Zustandsbewertung und Schädigungsbeobachtung ideal geeignet ist.

In diesem Beitrag werden Ergebnisse von Ultraschalllaufzeitmessungen an druckbeanspruchten Betonprobekörpern präsentiert. Die Ergebnisse wurden im Rahmen einer Literaturstudie gesammelt und durch eigene Untersuchungen ergänzt. Die Untersuchungen erfolgten an einem höherfesten Normalbeton im kraft‐ und weggeregelten Druckversuch. Es wird gezeigt, dass die sich mit steigender Druckbeanspruchung im Beton formierenden Risse zu einer deutlichen Abnahme der Ultraschallgeschwindigkeit führen. Zudem konnte festgestellt werden, dass der Bruch des Probekörpers durch die Änderung der Ultraschallgeschwindigkeit wesentlich deutlicher angezeigt wird, als das in einer Spannungsdehnungslinie abzulesen ist.

Ultrasonic investigations on compressive stressed concrete specimen

Ultrasonic measurement methods are already offering in various scientific disciplines (e.g. medicine, biology) an enormous performance potential. But also in other construction‐related sectors (e.g. steel construction, natural stone test) or in the field of geosciences the ultrasonic measurement technology is used successfully and multiple. In contrast the application in concrete construction is clearly underdeveloped, but especially laboratory tests show that it is ideally suitable for condition assessment and damage observation.

In this paper results are presented of ultrasonic transmission time measurements of compressive loaded concrete specimens. The results were collected as part of a literature study and supplemented by own investigations. The investigations were performed at a normal strength concrete in force‐ and stroke controlled compression tests. It is shown that the crack formation by increasing compressive stresses leads to a significant decrease in the ultrasonic pulse velocity. In addition, it was found that the fracture of the specimen is indicated by the change in ultrasonic pulse velocity substantially clearly than can be read in a stress‐strain curve.
Zur Verdrehsteifigkeit von durch Wandscheiben ausgesteiften Gebäuden
Authors: Brandt Bernd
Published: November 2015

Für ein Gebäude mit Wandscheiben als aussteifenden lotrechten Bauteilen lässt sich für Biegebeanspruchungen mithilfe der Labilitätszahlen αy2 und αz2 auf einfache Weise beurteilen, ob eine Berechnung nach Theorie II. Ordnung erforderlich ist. Zum Nachweis von Verdrehbeanspruchungen ist der Aufwand erheblich größer. In den Normen und der Literatur sind Konstruktionsprinzipien angegeben, bei deren Einhaltung auf einen entsprechenden Nachweis verzichtet werden kann. Diese Regeln werden durch eine mechanisch anschauliche Ableitung ersetzt: Wenn bei einem für Biegebeanspruchungen genügend ausgesteiften Gebäude der Wölbradius größer als der Last‐Trägheitsradius ist, kann auf weitergehende Nachweise nach Theorie II. Ordnung verzichtet werden, das Gebäude ist gegen Verdrehbeanspruchungen ausreichend ausgesteift.

Die Vorgehensweise ist durch Beispiele erläutert. Hinweise zu den Normen und baupraktische Angaben vervollständigen die Abhandlung.

Torsional stiffness by wall panels braced buildings

The bending stress of a building with wall panels of stiffening vertical components, can be assessed in a simple manner with the support of lability numbers αy2 and αz2 to verify whether a calculation according to theory II. order is required. The effort to verify twisting stress is considerably greater. The principal design is given in standard as well as in literature and can be dispensed with, in compliance to the supporting evidence. These rules are replaced by a mechanically illustrative derative: in case the warping radius is greater than the load‐radius of gyration in a, for bending stress, sufficiently braced building, it is possible to dispense with further evidence. The building is braced sufficiently against torsional stress.

The procedure is illustrated by means of examples. Notes on the standard and practical construction details complete the treatise.
Hospitalhof Stuttgart
Authors: Peter Boris , Pfaff Klaus , Sonntag Daniel
Published: November 2015

Der neue Hospitalhof in Stuttgart ist als Zentrum für Erwachsenenbildung, Kunst und Kultur weit über die Stadtgrenzen hinaus bekannt. Es ist der zentrale Verwaltungs‐ und Versammlungsort der Evangelischen Kirche in der Landeshauptstadt und u. a. Ort der Landessynode. Das Tragwerk des architektonischen Entwurfs von Lederer Ragnarsdóttir Oei Architekten wurde von Knippers Helbig Advanced Engineering entworfen und umgesetzt. Die räumlich komplexe Struktur wurde durchgängig von der Entwurfs‐ bis in die Ausführungsphase an einem digitalen räumlichen Gebäudemodell entwickelt. Der folgende Bericht beschreibt den Umgang mit räumlichen Tragstrukturen im Hochbau und zeigt die Potenziale einer frühzeitigen BIM‐Planung (BIM: Building Information Modeling, deutsch: Gebäudemodell) anhand konkreter Beispiele und Erfahrungen auf.

Hospitalhof Stuttgart – about three‐dimensional structures, BIM and the chance for a paradigm shift

As a center of adult education, culture and art, the new Hospitalhof in Stuttgart is known way beyond the city surrounds. It is the central administration and meeting place for the Protestant Church of the greater Stuttgart Metropolitan Area, as well as the regional synod. The load‐bearing structure of the new building, which has been designed by Lederer Ragnarsdóttir Oei Architects, has been designed and implemented by Knippers Helbig Advanced Engineering. The complex space structure has been completely developed from schematic design through construction documents on the basis of a three‐dimensional digital building model. The following report describes dealing with three‐dimensional structures in building construction und shows the potentials of an early BIM‐planning (BIM: Building Information Modeling) based on specific examples and experiences.
Linking hydrolysis performance to Trichoderma reesei cellulolytic enzyme profile
Authors: Lehmann Linda , Rønnest Nanna P. , Jørgensen Christian I. , Olsson Lisbeth , Stocks Stuart M. , Jørgensen Henrik S. , Hobley Timothy
Published: November 2015

Trichoderma reesei expresses a large number of enzymes involved in lignocellulose hydrolysis and the mechanism of how these enzymes work together is too complex to study by traditional methods, for example, by spiking with single enzymes and monitoring hydrolysis performance. In this study, a multivariate approach, partial least squares regression, was used to see whether it could help explain the correlation between enzyme profile and hydrolysis performance. Diverse enzyme mixtures were produced by T. reesei Rut‐C30 by exploiting various fermentation conditions and used for hydrolysis of washed pretreated corn stover as a measure of enzyme performance. In addition, the enzyme mixtures were analyzed by liquid chromatography–tandem mass spectrometry to identify and quantify the different proteins. A multivariate model was applied for the prediction of enzyme performance based on the combination of different proteins present in an enzyme mixture. The multivariate model was used for identification of candidate proteins that are correlated to enzyme performance on pretreated corn stover. A very large variation in hydrolysis performance was observed and this was clearly caused by the difference in fermentation conditions. Besides β‐glucosidase, the multivariate model identified several xylanases, Cip1 and Cip2, as relevant proteins to study further. Biotechnol. Bioeng. 2016;113: 1001–1010. © 2015 Wiley Periodicals, Inc.
Molecular variation of the nonribosomal peptide‐polyketide siderophore yersiniabactin through biosynthetic and metabolic engineering
Authors: Ahmadi Mahmoud Kamal , Fawaz Samar , Fang Lei , Yu Zhipeng , Pfeifer Blaine A
Published: November 2015

The production of the mixed nonribosomal peptide‐polyketide natural product yersiniabactin (Ybt) has been established using E. coli as a heterologous host. In this study, precursor‐directed biosynthesis was used to generate five new analogs of Ybt, demonstrating the flexibility of the heterologous system and the biosynthetic process in allowing compound diversity. A combination of biosynthetic and cellular engineering was then used to influence the production metrics of the resulting analogs. First, the cellular levels and activity of FadL, a hydrocarbon transport protein, were tested for subsequent influence upon exogenous precursor uptake and Ybt analog production with a positive correlation observed between FadL over‐production and analog formation. Next, a Ybt biosynthetic editing enzyme was removed from the heterologous system which decreased native compound production but increased analog formation. A final series of experiments enhanced endogenous anthranilate towards complete pathway formation of the associated analog which showed a selective ability to bind gold. Biotechnol. Bioeng. 2016;113: 1067–1074. © 2015 Wiley Periodicals, Inc.
Mechanistic modeling of enzymatic hydrolysis of cellulose integrating substrate morphology and cocktail composition
Authors: Huron Maïté , Hudebine Damien , Lopes Ferreira Nicolas , Lachenal Dominique
Published: November 2015

A mechanistic model of enzymatic hydrolysis taking into account the morphology of the cellulosic particles and its evolution with time was developed. The individual behavior of the main enzymes involved in the reaction (cellobiohydrolases, endoglucanases, and β‐glucosidases), as well as synergy effects, were also included. A large panel of experimental tests was done to fit and validate the model. This database included different enzymes mixtures and operating conditions and allowed to determine and compare with accuracy the adsorption and kinetic parameters of the different enzymes. Model predictions on short hydrolysis times were very satisfactory. On longer times, a deactivation constant was added to represent the hydrolysis slowdown. The model also allowed to predict the impact of enzymes ratios and initial substrate parameters (chain length distribution, polymerization degree) on hydrolysis, and to follow the evolution of these parameters with time. This model revealed general trends on the impact of cellulose morphology on hydrolysis. It is a useful tool to better understand the mechanisms involved in enzymatic hydrolysis of cellulose and to determine optimal cellulolytic cocktails for process design. Biotechnol. Bioeng. 2016;113: 1011–1023. © 2015 Wiley Periodicals, Inc.
Lactic acid production from cellobiose and xylose by engineered Saccharomyces cerevisiae
Authors: Turner Timothy L. , Zhang Guo‐Chang , Oh Eun Joong , Subramaniam Vijay , Adiputra Andrew , Subramaniam Vimal , Skory Christopher D. , Jang Ji Yeon , Yu Byung Jo , Park In , Jin Yong‐Su
Published: November 2015

Efficient and rapid production of value‐added chemicals from lignocellulosic biomass is an important step toward a sustainable society. Lactic acid, used for synthesizing the bioplastic polylactide, has been produced by microbial fermentation using primarily glucose. Lignocellulosic hydrolysates contain high concentrations of cellobiose and xylose. Here, we constructed a recombinant Saccharomyces cerevisiae strain capable of fermenting cellobiose and xylose into lactic acid. Specifically, genes (cdt‐1, gh1‐1, XYL1, XYL2, XYL3, and ldhA) coding for cellobiose transporter, β‐glucosidase, xylose reductase, xylitol dehydrogenase, xylulokinase, and lactate dehydrogenase were integrated into the S. cerevisiae chromosomes. The resulting strain produced lactic acid from cellobiose or xylose with high yields. When fermenting a cellulosic sugar mixture containing 10 g/L glucose, 40 g/L xylose, and 80 g/L cellobiose, the engineered strain produced 83 g/L of lactic acid with a yield of 0.66 g lactic acid/g sugar (66% theoretical maximum). This study demonstrates initial steps toward the feasibility of sustainable production of lactic acid from lignocellulosic sugars by engineered yeast. Biotechnol. Bioeng. 2016;113: 1075–1083. © 2015 Wiley Periodicals, Inc.
N‐Lauroylation during the Expression of Recombinant N‐Myristoylated Proteins: Implications and Solutions
Authors: Flamm Andrea Gabriele , Le Roux Anabel‐Lise , Mateos Borja , Díaz‐Lobo Mireia , Storch Barbara , Breuker Kathrin , Konrat Robert , Pons Miquel , Coudevylle Nicolas
Published: November 2015

Incorporation of myristic acid onto the N terminus of a protein is a crucial modification that promotes membrane binding and correct localization of important components of signaling pathways. Recombinant expression of N‐myristoylated proteins in Escherichia coli can be achieved by co‐expressing yeast N‐myristoyltransferase and supplementing the growth medium with myristic acid. However, undesired incorporation of the 12‐carbon fatty acid lauric acid can also occur (leading to heterogeneous samples), especially when the available carbon sources are scarce, as it is the case in minimal medium for the expression of isotopically enriched samples. By applying this method to the brain acid soluble protein 1 and the 1–185 N‐terminal region of c‐Src, we show the significant, and protein‐specific, differences in the membrane binding properties of lauroylated and myristoylated forms. We also present a robust strategy for obtaining lauryl‐free samples of myristoylated proteins in both rich and minimal media.
Surface Segregation of Fe in Pt–Fe Alloy Nanoparticles: Its Precedence and Effect on the Ordered‐Phase Evolution during Thermal Annealing
Authors: Prabhudev Sagar , Bugnet Matthieu , Zhu Guo‐Zhen , Bock Christina , Botton Gianluigi A.
Published: November 2015

The front cover artwork for Issue 22/2015 is provided by the Microscopy of Nanoscale Materials Research Group at McMaster University, Canada. The image depicts the marriage between in situ heating and advanced electron microscopy techniques that enabled this research team to track structural, compositional, and configurational evolution of the same alloy nanoparticle over the course of heat treatment. See the Full Paper itself at http://dx.doi.org/10.1002/cctc.201500380.
Arsenic Removal and Biotransformation Potential of Exiguobacterium Isolated From an Arsenic‐Rich Soil of Chhattisgarh, India
Authors: Pandey Neha , Bhatt Renu
Published: November 2015

The presence of arsenic (As) in soil and groundwater has become a serious environmental issue of various regions of India. A haloalkaliphilic Exiguobacterium sp. (As‐9) was isolated via enrichment culture technique from an arsenic‐rich soil of the Rajnandgaon district in the state of Chhattisgarh, India, and characterized as a novel arsenic removing bacteria. The isolate proved to be capable of growing over a broad range of arsenic concentration and was resistant to relatively high levels of arsenate (700 mM) and arsenite (180 mM). It displayed great potential in removing about 99% arsenic under aerobic conditions from the aqueous environment in ten days at 37°C at 100 rpm. Electron microscopy revealed a fourfold increase in the cell size due to intracellular accumulation of arsenic. Selective enzyme assays confirmed that the two intracellular enzymes, namely arsenate reductase and arsenite oxidase played a significant role in arsenate reduction and arsenite oxidation, respectively, thereby contributing to the effective removal of arsenic. These results provide evidence for the occurrence of two distinct mechanisms involved in arsenic resistance; one via arsenate reduction and the other via arsenite oxidation. Moreover, the study reports for the first time the role of arsenic transforming bacteria from this region which could resist and transform exceptionally high concentrations of arsenic oxyanions. Such metabolically active bacterial strain may find application in the treatment of arsenic contaminated soil and aquifers in the near future.
Effect of Cross‐Link Density on Carbon Dioxide Separation in Polydimethylsiloxane‐Norbornene Membranes
Authors: Hong Tao , Niu Zhenbin , Hu Xunxiang , Gmernicki Kevin , Cheng Shiwang , Fan Fei , Johnson J. Casey , Hong Eunice , Mahurin Shannon , Jiang De‐en , Long Brian , Mays Jimmy , Sokolov Alexei , Saito Tomonori
Published: November 2015

Invited for this month′s cover is the team of researchers at Oak Ridge National Laboratory and several research groups at the University of Tennessee, Knoxville. The image shows the use of cross‐linked polydimethylsiloxane–norbornene membranes to separate CO2 from flue gas. The Full Paper itself is available at 10.1002/cssc.201500903.
Texture‐based segmentation and a new cell shape index for quantitative analysis of cell spreading in AFM images
Authors: Tiryaki Volkan Müjdat , Adia‐Nimuwa Usienemnfon , Ayres Virginia M. , Ahmed Ijaz , Shreiber David I.
Published: November 2015

A new cell shape index is defined for use with atomic force microscopy height images of cell cultures. The new cell shape index reveals quantitative cell spreading information not included in a conventional cell shape index. A supervised learning‐based cell segmentation algorithm was implemented by texture feature extraction and a multi‐layer neural network classifier. The texture feature sets for four different culture surfaces were determined from the gray level co‐occurrence matrix and local statistics texture models using two feature selection algorithms and by considering computational cost. The quantitative morphometry of quiescent‐like and reactive‐like cerebral cortical astrocytes cultured on four different culture environments was investigated using the new and conventional cell shape index. Inclusion of cell spreading with stellation information through use of the new cell shape index was shown to change biomedical conclusions derived from conventional cell shape analysis based on stellation alone. The new CSI results showed that the quantitative astrocyte spreading and stellation behavior was induced by both the underlying substrate and the immunoreactivity of the astrocytes. © 2015 International Society for Advancement of Cytometry
Dietary supplements: What's in a name? What's in the bottle?
Authors: Marcus Donald M.
Published: November 2015

The Dietary Supplement Health and Education Act of 1994 (DSHEA), which arbitrarily classified herbals and other medicinal products as dietary supplements, obscured fundamental differences between two classes of products. Authentic supplements to the diet, such as multivitamins or calcium, have nutritional value and are safe. Herbals are used worldwide as medicines, they do not supplement the diet, they may cause severe adverse events, and they should be regulated as medicines. DSHEA also prevented the Food and Drug Administration (FDA) from effectively regulating herbal supplements as medicines. One consequence of weak FDA regulatory oversight is the poor quality of herbals. FDA inspections of manufacturing facilities have revealed violations of good manufacturing practices in over half of facilities inspected, including unsanitary conditions and lack of product specifications. Moreover, many “all natural” herbals marketed for weight loss, enhancement of sexual health and improving sports performance are adulterated with prescription and over‐the‐counter medications that have caused adverse cardiovascular events. New procedures to authenticate the identity of plants used in herbals will neither detect adulteration by medications nor provide assurance of appropriate pharmacological activity or safety. Nonvitamin, nonmineral "supplements" should be regulated as medicines, but revision or repeal of DSHEA faces strong opposition in Congress. The marketing of botanical supplements is based on unfounded claims that they are safe and effective. Health professionals need to inform patients and the public that there is no reason to take herbal medicines whose composition and benefits are unknown, and whose risks are evident.
Breaking the gridlock: Regulation of dietary supplements in the United States
Authors: Kapoor Akshay , Sharfstein Joshua M.
Published: November 2015

Despite increasing use of dietary supplements by millions of consumers, regulation of these products has not kept pace with changes and risks in the market. A major reason for this policy gridlock is the inability of different parties to come to an agreement on a path forward. The purpose of this paper is to set out a new framework for regulation in which consumers, industry, and regulators can all find common ground. This framework is based on a conceptual shift from ‘benefit versus risk’, the model for prescription drugs, to ‘access with safety’. Steps should include registration of all dietary supplements to permit easier enforcement against rogue products, a stronger disclaimer explaining the limited role of FDA in evaluating structure/function product claims, the establishment of standard laboratory techniques for characterization of products, and more clear authority for the agency when safety concerns arise. Copyright © 2015 John Wiley & Sons, Ltd.
Hepatotoxicity associated with the dietary supplement OxyELITE Pro™ — Hawaii, 2013
Authors: Johnston David I. , Chang Arthur , Viray Melissa , Chatham‐Stephens Kevin , He Hua , Taylor Ethel , Wong Linda L. , Schier Joshua , Martin Colleen , Fabricant Daniel , Salter Monique , Lewis Lauren , Park Sarah Y.
Published: November 2015

Dietary supplements are increasingly marketed to and consumed by the American public for a variety of purported health benefits. On 9 September 2013, the Hawaii Department of Health (HDOH) was notified of a cluster of acute hepatitis and fulminant hepatic failure among individuals with exposure to the dietary supplement OxyELITE Pro™ (OEP). HDOH conducted an outbreak investigation in collaboration with federal partners. Physicians were asked to report cases, defined as individuals with acute onset hepatitis of unknown etiology on or after 1 April 2013, a history of weight‐loss/muscle‐building dietary supplement use during the 60 days before illness onset, and residence in Hawaii during the period of exposure. Reported cases’ medical records were reviewed, questionnaires were administered, and a product investigation, including chemical analyses and traceback, was conducted. Of 76 reports, 44 (58%) met case definition; of these, 36 (82%) reported OEP exposure during the two months before illness. No other common supplements or exposures were observed. Within the OEP‐exposed subset, two patients required liver transplantation, and a third patient died. Excessive product dosing was not reported. No unique lot numbers were identified; there were multiple mainland distribution points, and lot numbers common to cases in Hawaii were also identified in continental states. Product analysis found consumed products were consistent with labeled ingredients; the mechanism of hepatotoxicity was not identified. We report one of the largest statewide outbreaks of dietary supplement‐associated hepatotoxicity. The implicated product was OEP. The increasing popularity of dietary supplements raises the potential for additional clusters of dietary supplement‐related adverse events. Copyright © 2015 John Wiley & Sons, Ltd.
Experimental analysis of mating patterns in a clonal plant reveals contrasting modes of self‐pollination
Authors: Hu Yi , Barrett Spencer C. H. , Zhang Da‐Yong , Liao Wan‐Jin
Published: November 2015

Hermaphrodite plants commonly practice self‐fertilization (selfing), but the mechanisms responsible vary depending on the mode of self‐pollination, pollinator behavior, and degree of clonality. Whether selfing occurs within (autogamy) or between flowers (geitonogamy) is of evolutionary significance because their fitness consequences differ. We used floral manipulations and genetic markers to determine the relative contribution of autogamy and within‐ versus between‐ramet geitonogamy to the selfing rate of the bumblebee‐pollinated, clonal herbAconitum kusnezoffii. Data on flowering phenology and bumblebee foraging were also collected to determine opportunities for different modes of self‐pollination. Autogamy accounted for only 12% of the selfing rate with the remainder resulting from geitonogamy. Whole‐ramet emasculation of clones with multiple ramets reduced selfing by 78%, indicating that within‐ramet geitonogamy contributed significantly (68%) to total selfing. Selfing of single‐ramet plants was 44% less than multiple‐ramet plants, indicating that the contribution of between‐ramet geitonogamy was substantially less (20%) than within‐ramet geitonogamy, probably because of bumblebee foraging behavior. Our results demonstrate for the first time in a clonal plant that within‐ramet geitonogamy is substantially greater than between‐ramet geitonogamy and highlight the importance of considering the influence of clonal architecture and pollinator foraging on modes of self‐pollination.
A directed mutational approach demonstrates that a putative linoleate isomerase from Lactobacillus acidophilus does not hydrate or isomerize linoleic acid
Authors: Fibinger Michael P. C. , Freiherr von Saß G. Johannes , Herrfurth Cornelia , Feussner Ivo , Bornscheuer Uwe T.
Published: November 2015

Catalytic promiscuity of enzymes is a field of general interest and the application of enzymes, catalyzing more than one chemical reaction has also industrial relevance. Furthermore, comparing the evolutionary relationship in protein families serves as basis for their engineering and adaption in practical applications. Oleate hydratases (EC 4.2.1.53) and linoleate isomerases (EC 5.2.1.5) act on related substrates and share substantial sequence similarity, but catalyze different transformations. The intrinsic cofactor FAD is found in both enzyme classes, but seems to perform different functions: for isomerases a redox‐based mechanism was identified and for hydratases only a structural or charge stabilizing function was suggested. Several fatty acid converting reactions were found in Lactobacillus acidophilus including oleate hydratase and linoleate isomerase activity. Two genes that may encode these two enzymes were identified (GenBank AAV42528.1 and ABB43157.1), cloned, and the corresponding proteins were produced in E. coli, purified, and investigated. This revealed that only the oleate hydratase activity could be confirmed. As both enzymes differ by only three amino acids, a series of mutants was also created and investigated to shed light on their promiscuous behavior.

Practical applications: Bacterial isomerization or hydration of cis‐double bonds leading to the formation of trans‐double bonds or hydroxyl groups within fatty acids has been recognized to be useful for biocatalysis, since no additional cofactor recycling is required despite the presence of the cofactor FAD.

Lactobacillus acidophilus can convert unsaturated fatty acids to different products through an oleate hydratase and linoleate isomerase activity. The corresponding annotated proteins may differ by only three amino acids. This study, however, confirmed only one as an oleate hydratase, but the identification of the activity of the second protein remains elusive.
The application of alkaline and acidic electrolyzed water in the sterilization of chicken breasts and beef liver
Authors: Shimamura Yuko , Shinke Momoka , Hiraishi Miki , Tsuchiya Yusuke , Masuda Shuichi
Published: November 2015

The sterilization effect of a combination treatment with alkaline electrolyzed water (AlEW) and strong acidic electrolyzed water (StAEW) on fresh chicken breasts and beef liver was evaluated. Samples (1, 5, and 10 g) were inoculated with Salmonella Enteritidis NBRC3313, Escherichia coli ATCC 10798, Staphylococcus aureus FDA209P, and S. aureus C‐29 [staphylococcal enterotoxin A (SEA) productive strain] and subjected to a dipping combination treatment (4°C and 25°C for 3 min) with AlEW and StAEW. Combination treatment with AlEW and StAEW significantly reduced the bacteria, and reduction of more than 1 log colony‐forming units (CFU)/g was achieved. Furthermore, this combination treatment significantly decreased the SEA gene expression level in samples. Some quality variables of the meat samples such as pH, lipid oxidation, color, amino‐acid content, texture, and sensory characteristics showed no significant differences between the combination treatment with AlEW and StAEW and the untreated control.
Individualistic impact of unit operations of production, at household level, on some antinutritional factors in selected cowpea‐based food products
Authors: Bolade Mathew K.
Published: November 2015

The individualistic effect of unit operations of production, at household level, on some antinutritional factors in selected cowpea‐based food products (moin‐moin, akara, and gbegiri) was investigated. Four cowpea types (IT93K‐452‐1, IT95K‐499s‐35, IT97K‐568‐18, and market sample) were used for the study, whereas the three traditional food products were produced from each of the cowpea types, respectively. The results revealed that every unit operation involved in the production of moin‐moin, akara or gbegiri contributed to the overall reduction of trypsin inhibitor activity (TIA), phytic acid (PA), and tannin; though at varying degrees. In the production of moin‐moin, the major contributions to the overall reduction in TIA were from steaming (64.2–72.0%), second‐stage soaking (9.7–11.9%), and dehulling (9.4–10.2%). The contributions to the overall reduction in PA were from dehulling (34.0–40.4%), preliminary soaking (15.4–21.0%), and steaming (7.8–14.0%), whereas that of tannin were from dehulling (39.7–47.6%), steaming (19.6–24.7%), and preliminary soaking (9.8–15.9%). For akara production, the major contributions to TIA reduction were from deep frying (64.2–72.0%), second‐stage soaking (9.7–11.9%), and dehulling (9.4–10.2%). The PA reduction was from dehulling (34.0–40.4%), preliminary soaking (15.4–21.0%), and deep frying (9.6–15.9%), whereas that of tannin reduction was from dehulling (39.7–47.6%), deep frying (20.7–25.3%), and preliminary soaking (9.8–15.9%). In the production of gbegiri, the overall reduction in TIA was contributed from pressure cooking (79.0–84.8%), preliminary soaking (5.8–11.3%), and dehulling (9.4–10.2%). The reduction in PA was contributed by dehulling (34.0–40.4%), pressure cooking (24.7–35.0%), and preliminary soaking (15.4–21.0%), whereas the overall reduction in tannin content was similarly contributed by dehulling (39.7–47.6%), pressure cooking (29.8–34.4%), and preliminary soaking (9.8–15.9%).
Changes in flavor volatile composition of oolong tea after panning during tea processing
Authors: Sheibani Ershad , Duncan Susan E. , Kuhn David D. , Dietrich Andrea M. , Newkirk Jordan J. , O'Keefe Sean F.
Published: November 2015

Panning is a processing step used in manufacturing of some varieties of oolong tea. There is limited information available on effects of panning on oolong tea flavors. The goal of this study was to determine effects of panning on flavor volatile compositions of oolong using Gas Chromatography‐Mass Spectrometry (GC‐MS) and Gas Chromatography‐Olfactometry (GC‐O). SDE and SPME techniques were applied for extraction of volatiles in panned and unpanned teas. A total of 190 volatiles were identified from SDE and SPME extractions using GC‐MS and GC‐O. There were no significant differences (P > 0.05) in aldehyde or terpene contents of unpanned and panned tea. However, alcohols, ketones, acids and esters contents were significantly reduced by panning. Among 12 major volatiles previously used for identification and quality assessment of oolong tea, trans nerolidol, 2‐ hexenal, benzaldehyde, indole, gernaiol, and benzenacetaldehyde contents were significantly decreased (P < 0.05) by panning. Panning increased (P < 0.05) contents of linalool oxide, cis jasmone, and methyl salicylate. The GC‐O study also showed an increase of aroma active compounds with sweet descriptions and decrease of aroma active compounds with fruity and smoky descriptions after panning. Panning significantly changes the volatile compositions of the tea and created new aroma active compounds. Results from this study can be used in quality assessment of panned oolong tea.
A study on sensory properties of sodium reduction and replacement in Asian food using difference‐from – control test
Authors: Leong Jasmine , Kasamatsu Chinatsu , Ong Evelyn , Hoi Jia Tse , Loong Mann Na
Published: November 2015

This study examined the effects of sodium reduction and flavor enhancers on the sensory profile of two types of hawker foods commonly consumed in Singapore, namely chicken rice and mee soto broth. The ‘difference‐from‐control’ test was the method adopted in this study involving 24–29 trained panelists. Combinations included blind control, two levels of sodium reduction, and two levels of flavor enhancers in sodium‐reduced recipes. In the sodium‐reduced recipes, two levels of NaCl, 0.48% and 0.55%, for chicken rice, and 0.76% and 0.86% for mee soto (equivalent to 31% and 22% reduction in NaCl), were used. Monosodium glutamate (MSG) or Ajiplus® (a blend of MSG and nucleotides) at 0.20% and 0.40% were added to the recipes comprising a reduction of 40% in NaCl (equivalent to 31% and 22% reduction in sodium, respectively) compared with the control. It was found that the inclusion of MSG or Ajiplus® in 40% NaCl‐reduced recipe resulted in a significant increase in perception of umami taste (P < 0.05) when compared to the control. By adding flavor enhancers into the 40%‐reduced salt chicken rice recipes, the perception of saltiness was significantly increased when compared to 22% and 31% sodium reduced recipes. Similarly for mee soto broth, there was a significant increase in perception of chicken flavor, umami taste, mouthfeel sensation, and sweet taste (P < 0.05) with a decrease in the perception of sour and bitter taste when compared to control. By adding 0.40% MSG into the 40%‐reduced salt recipes, the perception of saltiness was maintained when compared with control.
Alpha and gamma oscillation amplitudes synergistically predict the perception of forthcoming nociceptive stimuli
Authors: Tu Yiheng , Zhang Zhiguo , Tan Ao , Peng Weiwei , Hung Yeung Sam , Moayedi Massieh , Iannetti Gian Domenico , Hu Li
Published: November 2015

Ongoing fluctuations of intrinsic cortical networks determine the dynamic state of the brain, and influence the perception of forthcoming sensory inputs. The functional state of these networks is defined by the amplitude and phase of ongoing oscillations of neuronal populations at different frequencies. The contribution of functionally different cortical networks has yet to be elucidated, and only a clear dependence of sensory perception on prestimulus alpha oscillations has been clearly identified. Here, we combined electroencephalography (EEG) and functional magnetic resonance imaging (fMRI) in a large sample of healthy participants to investigate how ongoing fluctuations in the activity of different cortical networks affect the perception of subsequent nociceptive stimuli. We observed that prestimulus EEG oscillations in the alpha (at bilateral central regions) and gamma (at parietal regions) bands negatively modulated the perception of subsequent stimuli. Combining information about alpha and gamma oscillations predicted subsequent perception significantly more accurately than either measure alone. In a parallel experiment, we found that prestimulus fMRI activity also modulated the perception of subsequent stimuli: perceptual ratings were higher when the BOLD signal was higher in nodes of the sensorimotor network and lower in nodes of the default mode network. Similar to what observed in the EEG data, prediction accuracy was improved when the amplitude of prestimulus BOLD signals in both networks was combined. These findings provide a comprehensive physiological basis to the idea that dynamic changes in brain state determine forthcoming behavioral outcomes. Hum Brain Mapp 37:501–514, 2016. © 2015 Wiley Periodicals, Inc.
The hepatic, biliary, and pancreatic network of stem/progenitor cell niches in humans: A new reference frame for disease and regeneration
Authors: Lanzoni Giacomo , Cardinale Vincenzo , Carpino Guido
Published: November 2015

Stem/progenitors for liver, biliary tree, and pancreas exist at early stages of development in the definitive ventral endoderm forming the foregut. In humans, they persist postnatally as part of a network, with evidence supporting their contributions to hepatic and pancreatic organogenesis throughout life. Multiple stem cell niches persist in specific anatomical locations within the human biliary tree and pancreatic ducts. In liver and pancreas, replication of mature parenchymal cells ensures the physiological turnover and the restoration of parenchyma after minor injuries. Although actively debated, multiple observations indicate that stem/progenitor cells contribute to repair pervasive, chronic injuries. The most primitive of the stem/progenitor cells, biliary tree stem cells, are found in peribiliary glands within extrahepatic and large intrahepatic bile ducts. Biliary tree stem cells are comprised of multiple subpopulations with traits suggestive of maturational lineage stages and yet capable of self‐replication and multipotent differentiation, being able to differentiate to mature liver cells (hepatocytes, cholangiocytes) and mature pancreatic cells (including functional islet endocrine cells). Hepatic stem cells are located within canals of Hering and bile ductules and are capable of differentiating to hepatocyte and cholangiocyte lineages. The existence, phenotype, and anatomical location of stem/progenitors in the adult pancreas are actively debated. Ongoing studies suggest that pancreatic stem cells reside within the biliary tree, primarily the hepatopancreatic common duct, and are rare in the pancreas proper. Pancreatic ducts and pancreatic duct glands harbor committed pancreatic progenitors. Conclusion: The hepatic, biliary, and pancreatic network of stem/progenitor cell niches should be considered as a framework for understanding liver and pancreatic regeneration after extensive or chronic injuries and for the study of human chronic diseases affecting these organs. (Hepatology 2016;64:277‐286)
The distribution of hepatitis B virus exposure and infection in a population‐based sample of U.S. Hispanic adults
Authors: Jung Molly , Kuniholm Mark H. , Ho Gloria Y.F. , Cotler Scott , Strickler Howard D. , Thyagarajan Bharat , Youngblood Marston , Kaplan Robert C. , del Amo Julia
Published: November 2015

Little is known regarding the prevalence and distribution of hepatitis B virus (HBV) infection in U.S. Hispanics/Latinos. We sought to determine the prevalence of HBV exposure (serum HBV core antibody; anti‐HBc), active HBV infection (serum HBV surface antigen; HBsAg), and vaccine‐induced HBV immunity (antibody against HBV surface antigen; anti‐HBs) in U.S. Hispanics/Latinos and consider how these data inform clinical screening recommendations. Our analysis included 11,999 women and men of the Hispanic Community Health Study/Study of Latinos (HCHS/SOL), a population‐based, household survey in four urban communities (Bronx, NY; Miami, FL; Chicago, IL; and San Diego, CA) of U.S. civilian, noninstitutionalized self‐identifying Hispanic/Latino adults ages 18‐74. Vaccine‐induced immunity was defined as detection of anti‐HBs, but not anti‐HBc. However, if anti‐HBc were present, it was considered evidence of exposure to HBV, with detection of HBsAg used to distinguish those with active HBV infection. Mean age was 45.7 years, and 7,153 were women. Vaccine‐induced immunity was greatest among those ages 18‐29 years (60.2% in women, 54% in men) and decreased with increasing age, regardless of country of birth. The prevalence of active HBV infection was 0.29% (95% confidence interval: 0.19‐0.43), but varied by country of birth. Those born in the Dominican Republic had the highest prevalence of HBV exposure (20.3% in women, 29.7% in men) and active HBV infection (0.95%). Conclusions: The overall age‐standardized prevalence of active HBV infection in Hispanic/Latino adults (0.29%) was no different from the general U.S. population estimate (0.27%) and did not exceed 2%, regardless of country of birth. These data do not support targeting HBV screening to US Hispanic/Latino adults based upon background. (Hepatology 2016;63:445–452)
The importance of the number of transplanted cells with dipeptidyl peptidase‐4 expression on the haematopoietic recovery and lymphocyte reconstitution in patients with multiple myeloma after autologous haematopoietic stem‐cell transplantation
Authors: Kopinska Anna , Krawczyk‐Kulis Małgorzata , Dziaczkowska‐Suszek Joanna , Bieszczad Katarzyna , Jagoda Krystyna , Kyrcz‐Krzemien Slawomira
Published: November 2015

Autologous haematopoietic stem cell transplantation (AHSCT) remains recommended treatment in the first remission in multiple myeloma (MM). In earlier research it has been suggested that there is an influence of the expression of dipeptidyl peptidase‐4 (CD26) on both the homing and lymphocyte reconstitution after AHSCT. The aim of the study is to investigate the influence of transplanted cells CD26+ on the haematopoietic recovery and lymphocyte reconstitution after AHSCT in MM. Forty eight patients with MM underwent AHSCT in our centre. Number of all CD26+ cells, CD26+ lymphocytes, CD26+ monocytes and CD26+ and CD34+ cells were measured in the harvested material. Number of lymphocyte's subpopulations (all lymphocytes CD3+, helpers, suppressors, natural killer (NK), cytotoxic NK and lymphocytes B) were measured in peripheral blood during regeneration after AHSCT. In both flow cytometry was used. On the basis of the analysis there was, as regards regeneration of haematopoietic cells after AHSCT, it was shown that a higher number of monocytes CD26+ improves the reconstitution of helper, suppressor and NK lymphocytes. A higher number of transplanted CD26+ lymphocytes accelerates the reconstitution of NK lymphocytes, whereas a higher number of all the cells CD26+ has a positive impact on the regeneration of cytotoxic NK lymphocytes. Copyright © 2015 John Wiley & Sons, Ltd.
Regulating self‐selection into private health insurance in Chile and the United States
Authors: Vargas Bustamante Arturo , Méndez Claudio A.
Published: November 2015

In the 1980s, Chile adopted a mixed (public and private) model for health insurance coverage similar to the one recently outlined by the Affordable Care Act in the United States (US). In such a system, a mix of public and private health plans offer nearly universal coverage using a combined approach of managed competition and subsidies for low‐income individuals. This paper uses a “most different” case study design to compare policies implemented in Chile and the US to address self‐selection into private insurance. We argue that the implementation of a mixed health insurance system in Chile without the appropriate regulations was complex, and it generated a series of inequities and perverse incentives. The comparison of Chile and the US healthcare reforms examines the different approaches that both countries have used to manage economic competition, address health insurance self‐selection and promote solidarity. Copyright © 2015 John Wiley & Sons, Ltd.
Lipophilic bioactive compounds in the oils recovered from cereal by‐products
Authors: Górnaś Paweł , Rudzińska Magdalena , Raczyk Marianna , Soliven Arianne
Published: November 2015

BACKGROUND

The by‐products of seven different cereal grains were investigated as a source of extractable oil, rich in lipophilic bioactive compounds.

RESULTS

Oil yields (g kg−1 DW) recovered from cereal by‐products were as follows: 189 (rice bran) > 112 (wheat germ) > 74 (corn bran) > 58 (oat bran) > 41 (buckwheat bran) > 39 (spelt bran) > 33 (wheat bran) > 27 (rye bran). The main fatty acids identified in the studied oil samples were palmitic acid (11.39–17.23%), oleic acid (11.76–42.73%), linoleic acid (35.54–62.65%) and α‐linolenic acid (1.05–9.46%). The range of total tocochromanols and phytosterols in the obtained oils was 0.369–3.763 and 1.19–35.24 g kg−1 of oil, respectively. The oils recovered from buckwheat and corn bran, and wheat germ were dominated by tocopherols (99.9, 84.2 and 96.5%, respectively), whereas the oat, rice, rye, spelt, wheat bran oils were rich in tocotrienols (73.9, 79.6, 78.1, 90.6 and 73.8%, respectively). The campesterol and β‐sitosterol constituted 10.1–32.5 and 30.4–63.7%, respectively, of total phytosterols contents identified in all of the studied samples.

CONCLUSION

The present study demonstrated that oils recovered from the cereal by‐products are richer sources of bioactive compounds, compared with traditional oils. © 2015 Society of Chemical Industry
Metal Laser Melting
Authors: Hartmann‐H'Lawatscheck Tina
Published: November 2015

Metal laser melting is enjoying growing interest. The process has made the leap from being used for rapid prototyping to developing into a recognised manufacturing technology. In the past, it was primarily used to produce prototypes but today, additive manufacturing is used in many industries for (small and medium) series manufacturing. Toolcraft is offering completely new possibilities in metal laser melting that are extremely cost‐effective. The additive manufacturing process built up a workpiece layer by layer, as the laser melts the material concerned in powdered form. This procedure is therefore characteristically different from turning and milling, which are known as subtractive methods. With these methods, the part is produced by the removal of material. In the innova­tive process, the design data for the manufacture of the part is divided into cross sections and then formed on top of one another during the melting process. The part is thus literally built up in a ‘3D’ way.