bluuebunny/crossref_metadata_2025 huggingface dataset:
Fatigue Behavior and Lifetime Prediction of Unidirectionally Wire Reinforced Lightweight Metal Matrix Composites
Authors: Merzkirch Matthias , Hammers Thilo , Reeb Andreas , Schwind Thomas , Riedl Sascha , Thiel Leon , Henschel Alexander , Kerscher Eberhard , Schulze Volker , Weidenmann Kay André
Published: January 2015

In the field of lightweight construction for transportation means, hybrid structures composed of high‐strength and low‐density materials exhibit a high potential for application. The composite extrusion process allows an easy embedding of metallic reinforcements into a multitude of light metal alloys. The current work shows that different metallic wire reinforced light alloys with a content of 11.1 vol% lead to a significant increase in lifetime of different aluminum and magnesium alloys under fully reversed stress controlled fatigue loading. Based on the knowledge of the quasi‐static behavior of the single components and the fatigue behavior of the matrix material, a new lifetime model is used to predict the lifetime for different unidirectionally reinforced material systems.
Efficient and Simple Surface Modification of Carbon Nanotubes by Dry Process Using hydrogen
Authors: Moon S.Y. , Ogasawara T. , Hanamitsu S. , Shioda K. , Inoue Y.
Published: January 2015

We study a novel method to modify carbon nanotubes (CNT) surfaces using hydrogen and develop a composite with epoxy resin. This method is effective for functionalization of CNT surfaces and for chemical and physical interactions with other materials. The C = C/C–C ratio increased until 20 min and decreased thereafter. In addition, the C–O peak decreased until 20 min and increased after 20 min. This indicates that the CNT surface was transferred with H. SEM observation revealed that excellent interfacial bonding is achieved between CNTs and epoxy resin. It affected the mechanical properties to CNT/Epoxy nanocomposite.
Perfect Extinction of Terahertz Waves in Monolayer Graphene over 2‐nm‐Wide Metallic Apertures
Authors: Park Hyeong‐Ryeol , Namgung Seon , Chen Xiaoshu , Lindquist Nathan C. , Giannini Vincenzo , Francescato Yan , Maier Stefan A. , Oh Sang‐Hyun
Published: January 2015

High carrier mobility and tunability in graphene enable fundamental studies for plasmonics and various applications. Despite its versatility, however, single‐layer graphene (SLG) suffers from poor coupling efficiency to electromagnetic waves, presenting a major challenge for photonic applications. Compared with visible or infrared radiation, terahertz (THz) waves exhibit higher absorption in SLG due to Drude‐like intraband transitions, but the wavelength‐to‐SLG size mismatch becomes even more dramatic. Here, we experimentally demonstrate 99% extinction of THz wave transmission when SLG covers the openings of 2‐nm‐wide (≈λ/1 000 000) slits through a metal film. By resonantly coupling THz waves through annular nanogaps, the extremely localized fields lead to near‐perfect extinction and strong absorption in SLG. Atomic‐layer lithography is used to produce these nanometer‐wide, millimeter‐long gaps over an entire 4‐in. wafer. Furthermore, by integrating these devices with an ionic liquid, enhanced intraband absorption in the SLG leads to 80% modulation of THz waves with an operational voltage as low as 1.5 V.
Repetitive Hole‐Mask Colloidal Lithography for the Fabrication of Large‐Area Low‐Cost Plasmonic Multishape Single‐Layer Metasurfaces
Authors: Zhao Jun , Jaber Sarah , Mulvaney Paul , Braun Paul V. , Giessen Harald
Published: January 2015

A novel fabrication method, multiple repetitions of hole‐mask colloidal nanolithography, is introduced to create single‐layer metasurfaces with complex, multishape plasmonic nanostructures that exhibit desired optical functionalities. Large‐area and low‐cost fabrication of different samples with independently tunable resonances are demonstrated. These single‐layer metasurfaces may find applications as multiline surface‐enhanced infrared absorption and broadband substrates. This fabrication method is particularly suited for the creation of large‐area, single‐layer C3‐rotationally symmetric, 3D chiral metasurfaces, and this approach circumvents common problems with elliptical birefringence and can be utilized for interaction with chiral substances.
Thermodynamic Studies on Polyvinylpyrrolidone Solution Systems Used for Fabrication of Electrospun Nanostructures: Effects of the Solvent
Authors: Nasouri Komeil , Shoushtari Ahmad Mousavi , Mojtahedi Mohammad Reza Mohaddes
Published: January 2015

In this research, we investigate the influence of polyvinylpyrrolidone (PVP) solution systems on the morphology of the PVP nanofibers fabricated by electrospinning of PVP solutions prepared in different organic solvents, including ethanol (EtOH), propanol (PrOH), chloroform, N‐methyl‐2‐pyrrolidone (NMP), and N,N‐dimethylformamide (DMF) and then compared with the experimental results. First, by considering the electrospun solutions behavior, the thermodynamic studies were evaluated then Hansen solubility theory was applied to select the desirable solvent systems. The dissolving power of the solvents for PVP was obtained in the following order: DMF > NMP >> chloroform > PrOH > EtOH. It seems that every solvent, which is able to dissolve PVP polymer, shows different spinning characteristics under identical conditions of processing parameters. By using PrOH, chloroform, and NMP solvents, electrospun nanofibers’ average diameter was decreased intensively but at the same time beads formation was observed. We investigated that EtOH was a desirable solvent for PVP to fabricate fibers with z micrometer diameter distribution, but because of its low dissolving power it is suitable for microfiber synthesis with the electrospinning process. Based on the Hansen theory and experimental results, the PVP/DMF solutions showed desirable characteristics for the electrospinning system. Furthermore, the PVP nanofiber's uniformity of the PVP/DMF solution was higher than other solvent systems, which mean that fiber diameter distribution is scanty than others. Finally, it has been demonstrated that with an appropriate solvent the nanofiber diameter distribution and formation of beads can be controlled by Hansen theory.
Coproduction of liquid transportation fuels and C6_C8 aromatics from biomass and natural gas
Authors: Niziolek Alexander M. , Onel Onur , Elia Josephine A. , Baliban Richard C. , Floudas Christodoulos A.
Published: January 2015

The coproduction of liquid transportation fuels and C6C8 aromatics from the thermochemical conversion of biomass and natural gas (BGTL+C6_C8) is investigated in this article. An optimization‐based process synthesis framework incorporating multiple synthesis gas conversion technologies, such as Fischer–Tropsch synthesis or methanol conversion, is described. Production of aromatics can proceed through several technologies, such as naphtha reforming and aromatization of hydrocarbons via a metal‐promoted H‐ZSM‐5 catalyst. This is the first article in the literature to incorporate an aromatics complex for the coproduction of liquid fuels and C6C8 petrochemicals within a rigorous process synthesis and deterministic global optimization framework. The optimal process topologies across several case studies are discussed and the results indicate that the coproduction of aromatics with liquid fuels can significantly increase the profitability of these refineries. © 2015 American Institute of Chemical Engineers AIChE J, 2015 2014 American Institute of Chemical Engineers AIChE J, 61: 831–856, 2015
Air separation with cryogenic energy storage: Optimal scheduling considering electric energy and reserve markets
Authors: Zhang Qi , Grossmann Ignacio E. , Heuberger Clara F. , Sundaramoorthy Arul , Pinto Jose M.
Published: January 2015

The concept of cryogenic energy storage (CES) is to store energy in the form of liquid gas and vaporize it when needed to drive a turbine. Although CES on an industrial scale is a relatively new approach, the technology is well known and essentially part of any air separation unit that utilizes cryogenic separation. In this work, the operational benefits of adding CES to an existing air separation plant are assessed. Three new potential opportunities are investigated: (1) increasing the plant's flexibility for load shifting, (2) storing purchased energy and selling it back to the market during higher‐price periods, and (3) creating additional revenue by providing operating reserve capacity. A mixed‐integer linear programming scheduling model is developed and a robust optimization approach is applied to model the uncertainty in reserve demand. The proposed model is applied to an industrial case study, which shows significant potential economic benefits. © 2015 American Institute of Chemical Engineers AIChE J, 61: 1547–1558, 2015
Lipid‐specific immunoglobulin M bands in cerebrospinal fluid are associated with a reduced risk of developing progressive multifocal leukoencephalopathy during treatment with natalizumab
Authors: Villar Luisa M. , Costa‐Frossard Lucienne , Masterman Thomas , Fernandez Oscar , Montalban Xavier , Casanova Bonaventura , Izquierdo Guillermo , Coret Francisco , Tumani Hayrettin , Saiz Albert , Arroyo Rafael , Fink Katharina , Leyva Laura , Espejo Carmen , Simó‐Castelló María , García‐Sánchez María I. , Lauda Florian , Llufriú Sara , Álvarez‐Lafuente Roberto , Olascoaga Javier , Prada Alvaro , Oterino Agustín , de Andrés Clara , Tintoré Mar , Ramió‐Torrentà Lluis , Rodríguez‐Martín Eulalia , Picón Carmen , Comabella Manuel , Quintana Ester , Agüera Eduardo , Díaz Santiago , Fernandez‐Bolaños Ricardo , García‐Merino Juan A. , Landete Lamberto , Menéndez‐González Manuel , Navarro Laura , Pérez Domingo , Sánchez‐López Fernando , Serrano‐Castro Pedro J. , Tuñón Alberto , Espiño Mercedes , Muriel Alfonso , Bar‐Or Amit , Álvarez‐Cermeño José C.
Published: January 2015

Objective

Progressive multifocal leukoencephalopathy (PML) is a serious side effect associated with natalizumab treatment in multiple sclerosis (MS). PML risk increases in individuals seropositive for anti–John Cunningham virus (JC) antibodies, with prolonged duration of natalizumab treatment, and with prior exposure to immunosuppressants. We explored whether the presence of lipid‐specific immunoglobulin M oligoclonal bands in cerebrospinal fluid (CSF; IgM bands), a recognized marker of highly inflammatory MS, may identify individuals better able to counteract the potential immunosuppressive effect of natalizumab and hence be associated with a reduced risk of developing PML.

Methods

We studied 24 MS patients who developed PML and another 343 who did not suffer this opportunistic infection during natalizumab treatment. Patients were recruited at 25 university hospitals. IgM bands were studied by isoelectric focusing and immunodetection. CSF lymphocyte counts were explored in 151 MS patients recruited at Ramon y Cajal Hospital in Madrid, Spain.

Results

IgM bands were independently associated with decreased PML risk (odds ratio [OR] = 45.9, 95% confidence interval [CI] = 5.9–339.3, p < 0.0001) in patients treated with natalizumab. They were also associated with significantly higher CSF CD4, CD8, and B‐cell numbers. Patients positive for IgM bands and anti‐JC antibodies had similar levels of reduced PML risk to those who were anti‐JC negative (OR = 1.55, 95% CI = 0.09–25.2, p = 1.0). Higher risk was observed in patients positive for anti‐JC antibodies and negative for IgM bands (19% of the total cohort, OR = 59.71, 95% CI = 13.6–262.2).

Interpretation

The presence of IgM bands reflects a process that may diminish the risk of PML by counteracting the excess of immunosuppression that may occur during natalizumab therapy. Ann Neurol 2015;77:447–457
Ligand‐Controlled Regiodivergent Palladium‐Catalyzed Decarboxylative Allylation Reaction to Access α,α‐Difluoroketones
Authors: Yang Ming‐Hsiu , Orsi Douglas L. , Altman Ryan A.
Published: January 2015

α,α‐Difluoroketones possess unique physicochemical properties that are useful for developing therapeutics and probes for chemical biology. To access the α‐allyl‐α,α‐difluoroketone substructure, complementary palladium‐catalyzed decarboxylative allylation reactions were developed to provide linear and branched α‐allyl‐α,α‐difluoroketones. For these orthogonal processes, the fluorination pattern of the substrate enabled the ligands to dictate the regioselectivity of the transformations.
Indolo‐Phakelline als β5‐spezifische nichtkovalente Proteasom‐Inhibitoren
Authors: Beck Philipp , Lansdell Theresa A. , Hewlett Nicole M. , Tepe Jetze J. , Groll Michael
Published: January 2015

Das Proteasom ist ein etabliertes Angriffsziel zur Behandlung von Krebs und Autoimmunerkrankungen. Die Anwendung von Proteasominhibitoren ist jedoch auf Blutkrebs beschränkt, da ihre peptidischen Grundgerüste und reaktiven Kopfgruppen ungünstige pharmakodynamische Eigenschaften mit sich bringen. Die Entdeckung neuer Leitstrukturen ist somit von grundlegender Bedeuteutung. Hier stellen wir die erste Kristallstruktur des Proteasoms im Komplex mit einem Indolo‐Phakellin vor, das sich strukturell von allen bisheringen Inhibitoren signifikant unterscheidet und einen einzigartigen, nichtkovalenten Bindemodus aufweist. Das pentacyclische Alkaloid bindet ausschließlich und spezifisch in die S3‐sub‐Tasche des proteasomalen β5‐Substratbindekanals und wird durch eine Halogenbrücke mit dem Proteinrückgrat stabilisiert. Der Ligand bietet ein ideales Grundgerüst für die strukturbasierte Entwicklung von Untereinheit‐spezifischen nichtpeptidischen Proteasomhemmstoffen.
Die Reaktion von Pentelidenkomplexen mit Carbodiimiden und Alkylaziden – ein direkter Weg zu viergliedrigen Heterocyclen
Authors: Seidl Michael , Kuntz Christian , Bodensteiner Michael , Timoshkin Alexey Y. , Scheer Manfred
Published: January 2015

Die Reaktion der Pentelidenkomplexe [Cp*E{W(CO)5}2] (E=P (1 a), As (1 b); Cp*=C5Me5) mit Carbodiimiden führt zu den neuen viergliedrigen Heterocyclen des Typs [Cp*C(NR)2E{W(CO)5}2] (E=P: R=iPr (2 a), Cy (3 a); E=As: R=iPr (2 b), Cy (3 b)). Die Reaktion des Phosphinidenkomplexes 1 a mit Alkylaziden ergibt die Triazaphosphetderivate [Cp*P{W(CO)5}N(R)NN{W(CO)5}] (R=Hex, Cy; 4). Diese beispiellosen viergliedrigen Triazaphosphetkomplexe können als stabilisierte Intermediate der Staudinger‐Reaktion betrachtet werden, die bisher noch nicht isoliert werden konnten. Alle erhaltenen Produkte wurden durch NMR‐ und IR‐Spektroskopie, Massenspektrometrie und durch Röntgenstrukturanalyse an Einkristallen charakterisiert.
Catalytic Asymmetric Hydrogenation of Pyrimidines
Authors: Kuwano Ryoichi , Hashiguchi Yuta , Ikeda Ryuhei , Ishizuka Kentaro
Published: January 2015

The asymmetric hydrogenation of pyrimidines proceeded with high enantioselectivity (up to 99 % ee) using an iridium catalyst composed of [IrCl(cod)]2, a ferrocene‐containing chiral diphosphine ligand (Josiphos), iodine, and Yb(OTf)3 (cod=1,5‐cyclooctadiene). The chiral catalyst converted various 4‐substituted pyrimidines into chiral 1,4,5,6‐tetrahydropyrimidines in high yield. The lanthanide triflate is crucial for achieving the high enantioselectivity as well as for activating the heteroarene substrate.
A Small‐Molecule Protein–Protein Interaction Inhibitor of PARP1 That Targets Its BRCT Domain
Authors: Na Zhenkun , Peng Bo , Ng Shukie , Pan Sijun , Lee Jun‐Seok , Shen Han‐Ming , Yao Shao Q.
Published: January 2015

Poly(ADP‐ribose)polymerase‐1 (PARP1) is a BRCT‐containing enzyme (BRCT=BRCA1 C‐terminus) mainly involved in DNA repair and damage response and a validated target for cancer treatment. Small‐molecule inhibitors that target the PARP1 catalytic domain have been actively pursued as anticancer drugs, but are potentially problematic owing to a lack of selectivity. Compounds that are capable of disrupting protein–protein interactions of PARP1 provide an alternative by inhibiting its activities with improved selectivity profiles. Herein, by establishing a high‐throughput microplate‐based assay suitable for screening potential PPI inhibitors of the PARP1 BRCT domain, we have discovered that (±)‐gossypol, a natural product with a number of known biological activities, possesses novel PARP1 inhibitory activity both in vitro and in cancer cells and presumably acts through disruption of protein–protein interactions. As the first known cell‐permeable small‐molecule PPI inhibitor of PAPR1, we further established that (−)‐gossypol was likely the causative agent of PARP1 inhibition by promoting the formation of a 1:2 compound/PARP1 complex by reversible formation of a covalent imine linkage.
Formation of silk fibroin hydrogel and evaluation of its drug release profile
Authors: de Moraes Mariana Agostini , Albrecht Mahl Cynthia Regina , Ferreira Silva Mariana , Beppu Marisa Masumi
Published: January 2015

Silk hydrogels are interesting materials to be used as matrix in controlled drug delivery devices. However, methods to accelerate fibroin gelation and allow the drug incorporation during the hydrogel preparation are needed in literature. In this article we report the preparation of silk fibroin hydrogels with addition of several contents of ethanol, used to accelerate fibroin gelation kinetics, and we also evaluate the potential of these hydrogels to be used as matrices for drug delivery. Chemical and conformational properties did not change despite the amount of ethanol incorporated in the hydrogel. Hydrogels containing diclofenac sodium dissolved in ethanol showed a faster initial release of the drug than hydrogels with the drug dissolved in water but equilibrium was reached later. This indicates a more sustained drug delivery from hydrogels in which the model drug was dissolved in ethanol. Fibroin hydrogels confirm their promising use as biopolymeric matrices for controlled drug release. © 2015 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2015, 132, 41802.
Poly(3‐hydroxybutyrate‐co‐3‐hydroxyvalerate) films for food packaging: Physical–chemical and structural stability under food contact conditions
Authors: Chea Vorleak , Angellier‐Coussy Hélène , Peyron Stéphane , Kemmer Diana , Gontard Nathalie
Published: January 2015

The objective of the present article is to bring new insights into the relationships between the structural and physical–chemical stability and the inertness of PHBV films with respect to the targeted food packaging application. It is concluded from overall migration tests that PHBV films can be used as food contact materials for any type of food. Functional properties of PHBV films (mechanical properties and water vapor permeability) were also very stable after contact at 40°C during 10 days with all food simulating liquids tested (water, acetic acid 3% (w/v), ethanol 20% (v/v), and iso‐octane), except with ethanol 95% (v/v). Ethanol 95% (v/v) was identified as the worst case for PHBV films, with a high sorption value and an increase in the water vapor permeability. This was mainly explained by a significant plasticizing effect, together with a decrease in both the molecular weight and the crystallinity degree of PHBV films. From an industrial point of view, it allows assessing that the packaging functions of PHBV are fulfilled all over the food supply chain. © 2015 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2016, 133, 41850.
Fiber preparation and mechanical properties of recycled polypropylene for reinforcing concrete
Authors: Yin Shi , Tuladhar Rabin , Shanks Robert A. , Collister Tony , Combe Mark , Jacob Mohan , Tian Ming , Sivakugan Nagaratnam
Published: January 2015

Polypropylene (PP) fibers have been widely used to reinforce concrete footpaths as an alternative to steel mesh. The reinforcing effect of the PP fiber is directly proportional to its tensile strength and Young modulus. This research explored the feasibility of using an improved melt spinning and hot drawing process to produce virgin and recycled PP fibers of high mechanical properties in an industrial scale. Commercial grade granules of virgin PP, recycled PP and HPDE were mixed in different proportions in preparing five different types of fibers. All the fibers obtained high tensile strength and Young modulus. A relationship between the structural parameters and mechanical properties was then established. It was observed that the melt spinning and hot drawing process formed both α‐form and β‐form crystals in the PP fibers, and significantly improved crystallinity from about 50% to 80%. © 2015 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2015, 132, 41866.
Biodegradable high oxygen barrier membrane for chilled meat packaging
Authors: Dong Tungalag , Yun Xueyan , Li Mengting , Sun Wenxiu , Duan Yan , Jin Ye
Published: January 2015

“Chilled” meat is more nutritional, healthy and hygienic than the meat kept at ambient temperature. “Poly(propylene carbonate) (PPC) and poly(vinly alcohol) (PVA) were used to prepare biodegradable three‐layer PPC/PVA/PPC films with high barrier and tensile properties. The potential benefits of the developed films were also evaluated on the shelf life of chilled meat products. Compared to PPC film, using 20 wt % PVA as an intermediate layer in PPC/PVA/PPC film remarkably enhanced oxygen barrier performance at 0 and 50 RH % by about 500 times, tensile strength by about 8 times, and Young's modulus by nine times, but no beneficial effect on water vapor barrier performance has been observed. A new “sandwich” type of completely biodegradable material with high barrier was obtained. The application of PPC/PVA20/PPC film as the packaging material of chilled meat was effectively kept the total viable count (TVC) and total volatile basic nitrogen (TVB‐N) to acceptable levels in chilled meats until 19th day of storage at 4°C, however, the spoilage occurred within 11th and 14th days of refrigerated storage in term of TVC and TVB‐N, respectively, in the chilled meats packed with only PPC. Herein, we report that PPC/PVA/PPC three‐layer film can be a promising well‐defined biodegradable material with excellent potential in chilled meat packaging. © 2015 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2015, 132, 41871.
Thermal and mechanical properties of multiple‐component aliphatic degradable polyurethanes
Authors: Poręba Rafał , Kredatusová Jana , Hodan Jiří , Serkis Magdalena , Špírková Milena
Published: January 2015

Macroscopic thermal and mechanical properties of complex aliphatic polycarbonate‐based polyurethane (PU) films containing degradable ester units in PU backbone were studied by a combination of several experimental techniques. Differential scanning calorimetry (DSC) revealed that the synthesized oligomeric diol (DL‐L) contributes (in addition to polycarbonate diol) to the formation of soft‐segment domains, while the hard‐segment domains are formed from 1,6‐diisocyanatohexane (HDI) and butane‐1,4‐diol (BD). Three main phase transitions were detected by DSC and by dynamic mechanical thermal analysis. Thermogravimetric analysis (TGA) of two‐component PUs showed that the PU made from DL‐L and HDI is the least thermostable product, while the PU made from polycarbonate diol and HDI is the most stable one. The differences in the thermal stability of different four‐component PUs are not important. Tensile properties very sensitively reflect the changes in composition and in microstructure of PU samples; the best tensile properties exhibits the degradable sample containing the equimolar ratio of hydroxyl groups of macrodiol, oligomeric diol DL‐L and butane‐1,4‐diol. © 2015 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2015, 132, 41872.
Injury and Subsequent Regeneration of Muscles for Activation of Local Innate Immunity to Facilitate the Development and Relapse of Autoimmune Myositis in C57BL/6 Mice
Authors: Kimura Naoki , Hirata Shinya , Miyasaka Nobuyuki , Kawahata Kimito , Kohsaka Hitoshi
Published: January 2015

Objective

To determine whether injury and regeneration of the skeletal muscles induce an inflammatory milieu that facilitates the development and relapse of autoimmune myositis.

Methods

The quadriceps of C57BL/6 mice were injured with bupivacaine hydrochloride (BPVC) and evaluated histologically. Macrophages and regenerating myofibers in the treated muscles and differentiating C2C12 myotubes were examined for cytokine expression. Mice were immunized with C protein fragments at the base of the tail and in the right hind footpads (day 0) to evoke systemic anti–C protein immunity and to induce local myositis in the right hind limbs. The contralateral quadriceps muscles were injured with BPVC or phosphate buffered saline (PBS) on day 7 or after spontaneous regression of myositis (day 42). The quadriceps muscle in nonimmunized mice was injured with BPVC on day 7. The muscles were examined histologically 14 days after treatment.

Results

The BPVC‐injured muscles had macrophage infiltration most abundantly at 3 days after the injection, with emergence of regenerating fibers from day 5. The macrophages expressed inflammatory cytokines, including tumor necrosis factor α, interleukin‐1β, and CCL2. Regenerating myofibers and C2C12 myotubes also expressed the cytokines. The BPVC‐injected muscles from nonimmunized mice had regenerating myofibers with resolved cell infiltration 14 days after treatment. In mice preimmunized with C protein fragments, the muscles injected with BPVC on day 7 as well as on day 42, but not those injected with PBS, had myositis accompanied by CD8+ T cell infiltration.

Conclusion

Injury and regeneration could set up an inflammatory milieu in the muscles and facilitate the development and relapse of autoimmune myositis.
Circulating Follicular Helper–Like T Cells in Systemic Lupus Erythematosus: Association With Disease Activity
Authors: Choi Jin‐Young , Ho John Hsi‐en , Pasoto Sandra G. , Bunin Viviane , Kim Sang Taek , Carrasco Solange , Borba Eduardo F. , Gonçalves Celio R. , Costa Priscila R. , Kallas Esper G. , Bonfa Eloisa , Craft Joseph
Published: January 2015

Objective

To assess circulating follicular helper T (Tfh)–like CD4+ T cells in patients with systemic lupus erythematosus (SLE) and determine their relationship to disease activity.

Methods

Blood samples from patients with SLE, as well as blood samples from patients with Behçet's disease (BD) and healthy individuals as controls, were analyzed. In all samples, circulating Tfh‐like cells were enumerated by flow cytometry, using, as markers, expression of CXCR5, inducible T cell costimulator (ICOS), and programmed death 1 (PD‐1) protein, as well as secretion of interleukin‐21 (IL‐21). The frequency of circulating Tfh‐like cells was compared to that of circulating plasmablasts (CD19+IgD−CD38+). In addition, the possible association of circulating Tfh‐like cells with the SLE Disease Activity Index (SLEDAI) was evaluated.

Results

The subset of circulating Tfh‐like T cells, identified as CXCR5highICOShighPD‐1high, was expanded in the blood of SLE patients compared to controls. Circulating Tfh‐like cells were found to produce IL‐21 and had lower expression of CCR7 as compared to that in circulating CXCR5high central memory T cells, thereby enabling their distinction. Expression of PD‐1, but not ICOS or CXCR5, was significantly elevated in circulating Tfh‐like cells from SLE patients compared to controls. PD‐1 expression among CXCR5high circulating Tfh‐like cells correlated with the SLEDAI, frequency of circulating plasmablasts, and anti–double‐stranded DNA antibody positivity, but not with disease duration or past organ injury; rather, this cell profile appeared to be a reflection of current active disease.

Conclusion

Circulating Tfh‐like cells are associated with disease activity in SLE, suggesting that their presence indicates abnormal homeostasis of T cell–B cell collaboration, with a causal relationship that is central to disease pathogenesis. These findings also suggest that circulating Tfh‐like cells provide a surrogate for aberrant germinal center activity in SLE, and that their PD‐1 expression offers a tool for measuring disease activity and monitoring the response to therapies.
Survival of Adults With Systemic Sclerosis Following Lung Transplantation: A Nationwide Cohort Study
Authors: Bernstein Elana J. , Peterson Eric R. , Sell Jessica L. , D'Ovidio Frank , Arcasoy Selim M. , Bathon Joan M. , Lederer David J.
Published: January 2015

Objective

Many transplant programs are hesitant to offer lung transplantation to patients with systemic sclerosis (SSc) due to concerns about extrapulmonary involvement that might affect survival. The aim of this study was to determine whether adults with SSc have higher 1‐year mortality rates after lung transplantation compared to those with interstitial lung disease (ILD) or pulmonary arterial hypertension (PAH) not due to SSc.

Methods

Using data provided by the United Network for Organ Sharing, we performed a retrospective cohort study of 229 adults with SSc, 201 with PAH, and 3,333 with ILD who underwent lung transplantation in the US between May 4, 2005 and September 14, 2012. We examined associations between diagnosis and 1‐year survival after lung transplantation using stratified Cox models adjusted for recipient, donor, and procedure factors.

Results

Adults with SSc undergoing lung transplantation in the US had a multivariable‐adjusted 48% relative increase in the 1‐year mortality rate compared to those with non–SSc‐related ILD (hazard ratio 1.48 [95% confidence interval 1.01–2.17]). However, we did not detect a difference in the risk of death at 1 year between those with SSc and those with non–SSc‐related PAH (hazard ratio 0.85 [95% confidence interval 0.50–1.44]).

Conclusion

A diagnosis of SSc may confer an increased risk of death 1 year following lung transplantation compared to a diagnosis of ILD, but this risk is similar to that of PAH, a widely accepted indication for lung transplantation. Future work should identify modifiable risk factors that can improve transplant outcomes in this population.
Transition‐Metal‐Catalyzed π‐Bond‐Assisted CH Bond Functionalization: An Emerging Trend in Organic Synthesis
Authors: Gandeepan Parthasarathy , Cheng Chien‐Hong
Published: January 2015

Transition‐metal‐catalyzed CH activation is considered to be an important tool in organic synthesis and has been accepted and widely used by chemists because it is straightforward, cost‐effective, and environmentally friendly. A variety of functional groups have been used to direct metal complexes and achieve regioselective CH activation. Most directing is achieved through the σ‐bond coordination of functional groups to the metal catalyst, followed by ortho‐selective CH bond cleavage. However, recent work has demonstrated that π‐coordinating functional groups can also assist in guiding metal complexes for site‐selective CH bond activation. This emerging approach significantly expands the scope of CH activation reactions in organic synthesis. Herein, recent developments in this field are summarized.
TPτ Model Transformation: A Systematic Modelling Framework to Handle Internal Time Delays in Control Systems
Authors: Galambos Péter , Baranyi Péter
Published: January 2015

Varying time delays are inherent and unavoidable properties of a large set of control systems causing stability issues in most cases. Control design methods that guarantee the stability, such as those based on the Lyapunov–Krasovskii functional, are mathematically highly complicated and therefore have hardly spread into everyday engineering practice. This paper introduces a systematic modelling and control design schema enabling a gateway between the different delayed system representations and the tensor product (TP) type convex polytopic models which allows the direct use of linear matrix inequality (LMI)‐based controller and observer synthesis. The approach presented assumes known, bounded, time‐varying internal time‐delays where the delay derivative is not considered. The proposed modelling scheme is demonstrated via a numerical example.
Expanding the substrate scope of chitooligosaccharide oxidase from Fusarium graminearum by structure‐inspired mutagenesis
Authors: Ferrari Alessandro R. , Lee Misun , Fraaije Marco W.
Published: January 2015

Chitooligosaccharide oxidase from Fusarium graminearum (ChitO) oxidizes N‐acetyl‐D‐glucosamine (GlcNAc) and its oligomers with high efficiency at the C1‐hydroxyl moiety while it shows poor or no activity with other carbohydrates. By sequence and structural comparison with other known carbohydrate oxidases (glucooligosaccharide oxidase from Acremonium strictum and lactose oxidase from Microdochium nivale) eleven mutants were designed to redirect the catalytic scope of ChitO for improved oxidation of lactose, cellobiose and maltose. The catalytic properties of the most interesting mutants were further improved by combining single mutations. This has resulted in the creation of a set of ChitO variants that display totally different substrate tolerances. One ChitO variant shows a dramatic improvement in catalytic efficiency towards oxidation of glucose, cellobiose, lactose, and maltose. We also describe a ChitO variant with the highest catalytic efficiency in GlcNAc oxidation so far reported in the literature. Biotechnol. Bioeng. 2015;112: 1074–1080. © 2015 Wiley Periodicals, Inc.
Engineering a thermostable fungal GH10 xylanase, importance of N‐terminal amino acids
Authors: Song Letian , Tsang Adrian , Sylvestre Michel
Published: January 2015

Xylanases are used in many industrial processes including pulp bleaching, baking, detergent, and the hydrolysis of plant cell wall in biofuels production. In this work we have evolved a single domain GH10 xylanase, Xyn10A_ASPNG, from Aspergillus niger to improve its thermostability. We introduced a rational approach involving as the first step a computational analysis to guide the design of a mutagenesis library in targeted regions which identified thermal important residues that were subsequently randomly mutagenized through rounds of iterative saturation mutagenesis (ISM). Focusing on five residues, four rounds of ISM had generated a quintuple mutant 4S1 (R25W/V29A/I31L/L43F/T58I) which exhibited thermal inactivation half‐life (t1/2) at 60°C that was prolonged by 30 folds in comparison with wild‐type enzyme. Whereas the wild‐type enzyme retained 0.2% of its initial activity after a heat treatment of 10 min at 60°C and was completely inactivated after 2 min at 65°C, 4S1 mutant retained 30% of its initial activity after 15 min heating at 65°C. Furthermore, the mutant melting temperature (Tm) increased by 17.4°C compared to the wild type. Each of the five mutations in 4S1 was found to contribute to thermoresistance, but the dramatic improvement of enzyme thermoresistance of 4S1 was attributed to the synergistic effects of the five mutations. Comparison of biochemical data and model structure between 4S1 and the wild‐type enzyme suggested that the N‐terminal coil of the enzyme is important in stabilizing GH10 xylanase structure. Based on model structure analyses, we propose that enforced hydrophobic interactions within N‐terminal elements and between N‐ and C‐terminal ends are responsible for the improved thermostability of Xyn10A_ASPNG. Biotechnol. Bioeng. 2015;112: 1081–1091. © 2015 Wiley Periodicals, Inc.
Hybrids of Copolymers of Fluorene and C60‐Carrying‐Carbazole with Semiconducting Single‐Walled Carbon Nanotubes
Authors: Toshimitsu Fumiyuki , Ozawa Hiroaki , Nakashima Naotoshi
Published: January 2015

Three different copolymers of C60‐carrying‐carbazole and fluorene units with different copolymer composition ratios were designed and synthesized. On the basis of photoluminescence, atomic force microscopy, and Vis‐NIR and Raman spectroscopic analysis, we found that these copolymers solubilize only semiconducting single‐walled carbon nanotubes (sem‐SWNTs) to form copolymer/sem‐SWNT hybrids, in which energy transfer from the copolymer/C60 moieties to the SWNTs was revealed. By comparing two possible hybrid structures with molecular‐mechanics simulations, the greatest stabilization was found when the C60 moieties lay on the sem‐SWNT surfaces.
Expedient Synthesis of C‐Aryl Carbohydrates by Consecutive Biocatalytic Benzoin and Aldol Reactions
Authors: Hernández Karel , Parella Teodor , Joglar Jesús , Bujons Jordi , Pohl Martina , Clapés Pere
Published: January 2015

The introduction of aromatic residues connected by a CC bond into the non‐reducing end of carbohydrates is highly significant for the development of innovative structures with improved binding affinity and selectivity (e.g., Caril‐sLex). In this work, an expedient asymmetric “de novo” synthetic route to new aryl carbohydrate derivatives based on two sequential stereoselectively biocatalytic carboligation reactions is presented. First, the benzoin reaction of aromatic aldehydes to dimethoxyacetaldehyde is conducted, catalyzed by benzaldehyde lyase from Pseudomonas fluorescens biovar I. Then, the α‐hydroxyketones formed are reduced by using NaBH4 yielding the anti diol. After acetal hydrolysis, the aldol addition of dihydroxyacetone, hydroxyacetone, or glycolaldehyde catalyzed by the stereocomplementary D‐fructose‐6‐phosphate aldolase and L‐rhamnulose‐1‐phosphate aldolase is performed. Both aldolases accept unphosphorylated donor substrates, avoiding the need of handling the phosphate group that the dihydroxyacetone phosphate‐dependent aldolases require. In this way, 6‐C‐aryl‐L‐sorbose, 6‐C‐aryl–L‐fructose, 6‐C‐aryl–L‐tagatose, and 5‐C‐aryl‐L‐xylose derivatives are prepared by using this methodology.
Poren nach Maß – Struktur‐Eigenschafts‐Beziehungen unter der chemiedidaktischen Lupe
Authors: Herzog Stefanie , Finlayson Odilla , Hickmann Katharina , Parchmann Ilka
Published: January 2015

Ein Verständnis von Struktur‐Eigenschafts‐Beziehungen ist relevant, wenn beobachtbare Eigenschaften auf Grundlage mikroskopischer Strukturen unter Einbeziehung verschiedener Modelle erklärt oder vorhergesagt werden sollen. Dabei ist es vor allem entscheidend, neben den einzelnen Atomen und funktionellen Gruppen auch auf das „große Ganze“ submikroskopischer Strukturen zu schauen, da häufig erst die vorhandenen Zwischenräume in Makromolekülen deren makroskopische Eigenschaften bedingen. Im vorliegenden Beitrag werden solche Wechselwirkungen zwischen Modellen und Eigenschaften auf verschiedenen Ebenen entlang eines forschend‐entwickelnden Unterrichtsgangs zum Thema „Poren nach Maß“ dargelegt und ausgewählte Aspekte einer Umsetzung für die Sekundarstufe I präsentiert. Die verschiedenen Niveaustufen bieten Zugänge für Lernende aller Altersklassen, und es werden neben den geforderten Methoden zur Erkenntnisgewinnung auch verfahrenstechnische bzw. industrielle Fragen zur Produktoptimierung aufgeworfen, denen die Lernenden nachgehen können.
Evaluation of Synergistic Effects of Resynchronization Therapy and a β‐Blocker Up‐titration Strategy Based on a Predefined Patient‐Management Program: The RESTORE Study
Authors: Palmisano Pietro , Ammendola Ernesto , D'Onofrio Antonio , Accogli Michele , Calò Leonardo , Ruocco Antonio , Rapacciuolo Antonio , Del Giorno Giuseppe , Bianchi Valter , Malacrida Maurizio , Valsecchi Sergio , Gronda Edoardo
Published: January 2015

Prior studies have suggested that a substantial number of eligible heart failure (HF) patients fail to receive β‐blocker therapy, or receive it at a suboptimal dose. The aim of this study is to assess the benefit of a predefined management program designed for β‐blocker up‐titration, evaluating the synergistic effect of cardiac resynchronization therapy (CRT) and β‐blockers in a HF population. The Resynchronization Therapy and β‐Blocker Titration (RESTORE) study is a prospective, case‐control, multicenter cohort study designed to test the hypothesis that a β‐blocker up‐titration strategy based on a predefined management program maximizes the beneficial effect of CRT, increasing the number of patients reaching the target dose of β‐blockers and improving their clinical outcome. All study patients receive an implantable defibrillator for CRT delivery in accordance with current guidelines. Enrollments started in December 2011 and are scheduled to end in December 2014. Approximately 250 consecutive patients will be prospectively enrolled in 6 Italian centers and followed up for 24 months after implantation. The primary endpoint is to demonstrate that CRT may allow titration of β‐blockers until the optimal dose, or at least to the effective dose, in patients with HF. This study might provide important information about the benefit of a predefined management program for β‐blocker up‐titration in patients receiving CRT. Moreover, assessment of health‐care utilization and the consumption of resources will allow estimating the potential utility of remote monitoring by means of an automated telemedicine system in facilitating the titration of β‐blockers in comparison with a standard in‐hospital approach.
In vivo clonal overexpression of neuroligin 3 and neuroligin 2 in neurons of the rat cerebral cortex: Differential effects on GABAergic synapses and neuronal migration
Authors: Fekete Christopher D. , Chiou Tzu‐Ting , Miralles Celia P. , Harris Rachel S. , Fiondella Christopher G. , Loturco Joseph J. , De Blas Angel L.
Published: January 2015

We studied the effect of clonal overexpression of neuroligin 3 (NL3) or neuroligin 2 (NL2) in the adult rat cerebral cortex following in utero electroporation (IUEP) at embryonic stage E14. Overexpression of NL3 leads to a large increase in vesicular gamma‐aminobutyric acid (GABA) transporter (vGAT) and glutamic acid decarboxylase (GAD)65 in the GABAergic contacts that the overexpressing neurons receive. Overexpression of NL2 produced a similar effect but to a lesser extent. In contrast, overexpression of NL3 or NL2 after IUEP does not affect vesicular glutamate transporter 1 (vGlut1) in the glutamatergic contacts that the NL3 or NL2‐overexpressing neurons receive. The NL3 or NL2‐overexpressing neurons do not show increased innervation by parvalbumin‐containing GABAergic terminals or increased parvalbumin in the same terminals that show increased vGAT. These results indicate that the observed increase in vGAT and GAD65 is not due to increased GABAergic innervation but to increased expression of vGAT and GAD65 in the GABAergic contacts that NL3 or NL2‐overexpressing neurons receive. The majority of bright vGAT puncta contacting the NL3‐overexpressing neurons have no gephyrin juxtaposed to them, indicating that many of these contacts are nonsynaptic. This contrasts with the majority of the NL2‐overexpressing neurons, which show plenty of synaptic gephyrin clusters juxtaposed to vGAT. Besides having an effect on GABAergic contacts, overexpression of NL3 interferes with the neuronal radial migration, in the cerebral cortex, of the neurons overexpressing NL3. J. Comp. Neurol. 523:1359–1378, 2015. © 2015 Wiley Periodicals, Inc.
Side‐Chain‐Bulk Effects on the Molecular Packing and Photovoltaic Performance of Benzotrithiophene–Benzooxadiazole Conjugated Copolymers
Authors: Lan Shang‐Che , Chang Chiao‐Kai , Wang Yi‐Chien , Wei Kung‐Hwa
Published: January 2015

Two alternating donor–acceptor conjugated polymers, PBTTBO‐C13C11 and PBTTBO‐C13C8, comprising 5‐alkylbenzo[1,2‐b:3,4‐b′:5,6‐d′′]trithiophene (BTT) as the donor and 4,7‐bis(4‐dodecylthien‐2‐yl)benzo[1,2,5]oxadiazole (BO) as the acceptor, with different alkyl side‐chain architectures on their BTT units are synthesized, and their bulk heterojunction photovoltaic properties when blended with the fullerene PC71BM are characterized. Even a slight change in the length of the alkyl chain of the BTT units influences the steric bulk to such a degree that it substantially affects the molecular packing of the polymers and the performance of their photovoltaic devices. The bulkier side chains of the polymer PBTTBO‐C13C11 not only prevent its crystallization, but also suppress its light‐absorption coefficient relative to that of PBTTBO‐C13C8, as evidenced by X‐ray diffraction and UV/Vis absorption studies, presumably because of weakened intermolecular interactions. Moreover, the polymer bearing bulkier side chains, PBTTBO‐C13C11, is less miscible with PC71BM than PBTTBO‐C13C8, and this characteristic determines the morphology of their annealed blended films, as shown by TEM studies. The best efficiency is obtained with a device containing an annealed PBTTBO‐C13C8/PC71BM (1/2 w/w) active layer that was maintained at 120 °C for 10 min, which shows a power conversion efficiency of 6.2 %, an open‐circuit voltage of 0.75 V, a short‐circuit current density of 12.6 mA cm−2, and a fill factor of 66 %.
Luminescent Carbon Dots for Logic Operations in Two Phases
Authors: Sk Md Palashuddin , Sailapu Sunil Kumar , Chattopadhyay Arun
Published: January 2015

Basic and higher integrated logic operations have been achieved by using luminescent carbon dots through interactions with metal ions and organic molecules in liquid dispersions as well as in the solid phase. The biphasic simple and complex logic systems could be potentially used for various analytical applications as well as for the detection of important elements in diverse environments.
Graphene Oxide Modified with Mesogenic Groups and Its Effect in Broad‐Band Reflectors
Authors: Wang Xiaomei , Cao Hangchao , Zhang Li , Zhang Ruirui , Wang Dong , Yang Zhou , He Wangli , Cao Hui , Yang Huai
Published: January 2015

The NH2‐terminated mesogenic group 4‐(6‐amine‐hexyloxy)‐4*‐cyan‐biphenyl is chemically grafted onto the carboxylic groups of graphene oxide (GO) through an amidation reaction. The resultant mesogenic‐group‐modified GO sheets (GO‐LC) are redispersed easily in common organic solvents, facilitating the structure characterization and device fabrication by solution processing. Broad‐band reflectors are obtained by doping different contents of GO‐LC nanosheets into chiral nematic liquid crystalline (N*‐LCs) media with a photopolymerization process. The experimental results show that both the bandwidth of the reflection spectrum and the location of the reflection band of the GO‐LC‐doped composite films are better than those of the N*‐LCs sample without GO‐LC doping. The effects of polymerization temperature and amount of GO‐LC dopant on the broad‐band reflection of the N*‐LC composite films are investigated.
Crystallization and stability of different protein crystal modifications: A case study of lysozyme
Authors: Yu Xiaoxi , Ulrich Joachim , Wang Jingkang
Published: January 2015

The crystallization, including both the phase diagram and the phase transition of hen egg white lysozyme (HEWL) was investigated. A tetragonal modification and a needle modification were obtained during crystallization. The phase diagram and stability of two modifications in both acid and basic pH solutions (pH 4.5, 8.0 and 9.0) were determined. Besides in acid solutions, the well‐known tetragonal crystals can also be obtained in basic solutions at low temperature (7 °C) while the needle like modification can only crystallize in a basic solution. Based on the phase diagram, phase transfer behavior was found to exist between the two modifications. In basic solutions, tetragonal modification can transfer to needle shaped crystals. This process can be affected by a changing of pH and temperature. While in acid buffer, the needle shaped crystals dissolve and tetragonal crystals crystallize and remain in solution.
Fe3W3C/WC/Graphitic Carbon Ternary Nanojunction Hybrids for Dye‐Sensitized Solar Cells
Authors: Liao Yongping , Xie Ying , Pan Kai , Wang Guofeng , Pan Qingjiang , Zhou Wei , Wang Lei , Jiang Baojiang , Fu Honggang
Published: January 2015

Fe3W3C/WC/graphitic carbon (GC) ternary nanojunction hybrids are synthesized through a solid‐state pyrolysis process for dye‐sensitized solar cells (DSSCs). First‐principles calculations have been first employed to investigate the adsorption energy between I3− and Fe3W3C and WC nanoclusters. Scanning Kelvin probe images indicate that the work function changes greatly due to the formation of ternary nanojunctions, which favor fast photoelectron transfer. A photoelectrical conversion efficiency of 7.1 % is achieved based on Fe3W3C/WC/GC hybrid counter electrodes, which is much higher than those of pure GC (5.02 %) and WC/GC hybrids (6.11 %). It has been further revealed that Fe3W3C/WC/GC hybrid counter electrodes exhibit the best catalytic performances according to relevant electrochemical measurements, which can be attributed to fast photoelectron transfer due to the ternary junctions and the addition of Fe3W3C with more catalytic metallic atoms.