bluuebunny/crossref_metadata_2025 huggingface dataset:
A Carbene Catalysis Strategy for the Synthesis of Protoilludane Natural Products
Authors: Hovey M. Todd , Cohen Daniel T. , Walden Daniel M. , Cheong Paul H.‐Y. , Scheidt Karl A.
Published: June 2017

The Armillaria and Lactarius genera of fungi produce the antimicrobial and cytotoxic mellolide, protoilludane, and marasmane sesquiterpenoids. We report a unified synthetic strategy to access the protoilludane, mellolide, and marasmane families of natural products. The key features of these syntheses are 1) the organocatalytic, enantioselective construction of key chiral intermediates from a simple achiral precursor, 2) the utility of a key 1,2‐cyclobutanediol intermediate to serve as a precursor to each natural product class, and 3) a direct chemical conversion of a protoilludane to a marasmane through serendipitous ring contraction, which provides experimental support for their proposed biosynthetic relationships.
Catalyst‐Controlled, Enantioselective, and Diastereodivergent Conjugate Addition of Aldehydes to Electron‐Deficient Olefins
Authors: Kan S. B. Jennifer , Maruyama Hiroki , Akakura Matsujiro , Kano Taichi , Maruoka Keiji
Published: June 2017

A chiral‐amine‐catalyzed enantioselective and diastereodivergent method for aldehyde addition to electron‐deficient olefins is presented. Hydrogen bonding was used as a control element to achieve unusual anti selectivity, which was further elucidated through mechanistic and computational studies.
Room temperature and low temperature toughness improvement in SAN/ASA blends by blending with CPE, HNBR, and BR
Authors: Mao Zepeng , Zhang Jun
Published: June 2017

Styrene‐acrylonitrile copolymer (SAN)/acrylonitrile‐styrene‐acrylate terpolymer (ASA) blends (75/25, wt/wt) was toughened by blending with impact modifiers including chlorinated polyethylene (CPE), hydrogenated nitrile butadiene rubber (HNBR), and butadiene rubber (BR) and the impact property was tested at four temperatures (–30, −15, 0, and 25 °C). The combination of CPE and HNBR was imported to toughen the SAN/ASA blends, indicating that CPE and HNBR had similar toughening effect at room temperature but HNBR exhibited a better performance at low temperature. When a little HNBR was substituted by BR, the impact strength improved dramatically with the total content of impact modifiers keeping at 30 phr. After 15 phr CPE, 10 phr HNBR and 5 phr BR were employed into blends together, the impact strength reached to a peak of 14 kJ/m2 at −30 °C while the impact strength of the blends individually toughened by 30 phr CPE or 30 phr HNBR was 5 or 12 kJ/m2, respectively. The toughening mechanism showed that the low glass‐transition temperature (–108 °C) of BR and the compatibilization between BR and matrix accounted for the improvement of toughness. Simultaneously, scanning electron microscopy, dynamic mechanical analysis, flexural and tensile properties, heat distortion temperature, and Fourier transform infrared spectroscopy were measured. © 2017 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2017, 134, 45364.
Thermal, mechanical, and rheological properties of graphite‐ and graphene oxide‐filled biodegradable polylactide/poly(ɛ‐caprolactone) blend composites
Authors: Botlhoko Orebotse Joseph , Ramontja James , Ray Suprakas Sinha
Published: June 2017

The effect of graphite (G) and graphene oxide (GO) dispersions on the thermal, mechanical, rheological properties of biodegradable polylactide (PLA)/poly(ɛ‐caprolactone) (PCL) blend composites has been comparatively investigated. Surface morphology analysis indicates that the degree of morphological stability depends on not only the loading of the filler but also enthalpic interaction between the filler surface and the polymer blend. A significant improvement in the elongation at break (43.8%), with well‐balance of modulus and strength characteristics, is observed for the G‐filled (0.25 wt %) blend composite, whereas the GO‐filled (0.05 wt %) ternary composite shows a strong (∼19 °C) improvement in the thermal stability. Furthermore, the dynamic modulus of the blends increased after composite formation; however, the degree of improvement is greater for the G‐filled blend composites. On the basis of the obtained results, we propose a general description of how the morphology and structure of the blend composites are related to the final properties. © 2017 Wiley Periodicals, Inc. J. Appl. Polym. Sci.2017,134, 45373.
A novel Bayesian inference soft sensor for real‐time statistic learning modeling for industrial polypropylene melt index prediction
Authors: Sun Yuanmeng , Wang Yalin , Liu Xinggao , Yang Chunhua , Zhang Zeyin , Gui Weihua , Chen Xu , Zhu Bochao
Published: June 2017

A novel real‐time soft sensor based on a sparse Bayesian probabilistic inference framework is proposed for the prediction of melt index in industrial polypropylene process. The Bayesian framework consists of a relevance vector machine for predicting melt index and a particle filtering algorithm for soft sensor optimization. An online correcting strategy is also developed for improving the performance of real‐time melt index prediction. The method takes advantages of the probabilistic inference and using prior statistical knowledge of polymerization process. Developed soft sensors are validated with ten public databases from UCI machine learning repository and real data from industrial polypropylene process. Experimental results indicate the effectiveness of proposed method and show the improvement in both prediction precision and generalization capability compared with the reported models in literatures. © 2017 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2017, 134, 45384.
Measuring text difficulty using parse‐tree frequency
Authors: Kauchak David , Leroy Gondy , Hogue Alan
Published: June 2017

Text simplification often relies on dated, unproven readability formulas. As an alternative and motivated by the success of term familiarity, we test a complementary measure: grammar familiarity. Grammar familiarity is measured as the frequency of the 3rd level sentence parse tree and is useful for evaluating individual sentences. We created a database of 140K unique 3rd level parse structures by parsing and binning all 5.4M sentences in English Wikipedia. We then calculated the grammar frequencies across the corpus and created 11 frequency bins. We evaluate the measure with a user study and corpus analysis. For the user study, we selected 20 sentences randomly from each bin, controlling for sentence length and term frequency, and recruited 30 readers per sentence (N = 6,600) on Amazon Mechanical Turk. We measured actual difficulty (comprehension) using a Cloze test, perceived difficulty using a 5‐point Likert scale, and time taken. Sentences with more frequent grammatical structures, even with very different surface presentations, were easier to understand, perceived as easier, and took less time to read. Outcomes from readability formulas correlated with perceived but not with actual difficulty. Our corpus analysis shows how the metric can be used to understand grammar regularity in a broad range of corpora.
Metal‐Ion Induced In Situ Ligand Oxidation for Self‐Assembled Clusters: from Bis(5‐(2‐pyridine‐2‐yl)‐1,2,4‐triazole‐3‐yl)methane to Alcohol or Ketone
Authors: Lin Wei‐Quan , Peng Yuan‐Yuan , Tong Lang , Jia Jian‐Hua , Liu Jun‐Liang , Chen Yan‐Cong , Chen Wen‐Bin , Tong Ming‐Liang
Published: June 2017

Hydrothermal reactions of metal nitrates and ligand bis(5‐(pyridine‐2‐yl)‐1,2,4‐triazol‐3‐yl)methane (H2L1) gave three cluster compounds, {Cr2}, {Zn12} and {Fe8}. Notably, methylene group of H2L1 was in situ oxidized either to hydroxymethylated (L2‐O)3− in the metallo‐ring {Zn12} or to a rigid carbonylated (L3=O)2− in the screw‐type {Fe8}. In light of comparative experimental results, NO3− was deduced to be of a catalytic role in the ligand oxidation. Metal ion could be regarded as an “induced” tool for clusters generation in self‐assembly process.
Die neue Kienlesbergbrücke in Ulm – Herausforderungen der Objektplanung im komplexen Baukontext
Authors: Akkermann Jan , Vieth Heinz‐Josef , Halaczek Bartlomiej
Published: June 2017

Die 270 m lange Kienlesbergbrücke ist die Verbindung für die neue Straßenbahnlinie 2 sowie Fußgänger und Radfahrer zwischen der Ulmer Innenstadt und der nordwestlich gelegenen Wissenschaftsstadt. Die Brücke überquert einen dichten Verkehrsknotenpunkt der Deutschen Bahn in unmittelbarer Nähe zum Ulmer Hauptbahnhof, bei dem zeitgleich die Zufahrt zum Portal des Albabstiegtunnels der Neubaustrecke Stuttgart–Ulm realisiert wird. Die komplexen geometrischen und bauzeitlichen Zwangspunkte bedingten eine hochgradig ungleichförmige Bauwerksgestaltung, welcher der Brückenentwurf auch formal im Kontext der historischen Umgebung gerecht wird. Der wellenförmige, im Querschnitt asymmetrische Überbau folgt als orthotrope Platte ausgebildet dem sich aus der Geometrie ergebenden Kraftfluss. Aufgrund Restriktionen im Baufeld wurde der semi‐integrale Stahlüberbau im Längsverschub erstellt.
Carbazole–azine based fluorescence ‘off–on’ sensor for selective detection of Cu2+ and its live cell imaging
Authors: Christopher Leslee Denzil Britto , Karuppannan Sekar , Vengaian Karmegam Muthu , Gandhi Sivaraman , Subramanian Singaravadivel
Published: June 2017

A new carbazole–azine based fluorescent sensor was synthesized and characterized. The selectivity of the sensor for Cu2+ over other counter ions in a dimethyl sulfoxide/H2O mixture was shown through enhancement in fluorescence – an off to on transformation. The specificity of the probe towards Cu2+ was evident in ultraviolet/visible, fluorescence, Fourier transform infrared and mass studies. Application of the probe in the cell imaging and cytotoxicity of living cells is illustrated.
Minimally invasive surgery and its impact on 30-day postoperative complications, unplanned readmissions and mortality
Authors: Sood A , Meyer C P , Abdollah F , Sammon J D , Sun M , Lipsitz S R , Hollis M , Weissman J S , Menon M , Trinh Q-D
Published: June 2017

Background

A critical appraisal of the benefits of minimally invasive surgery (MIS) is needed, but is lacking. This study examined the associations between MIS and 30-day postoperative outcomes including complications graded according to the Clavien–Dindo classification, unplanned readmissions, hospital stay and mortality for five common surgical procedures.

Methods

Patients undergoing appendicectomy, colectomy, inguinal hernia repair, hysterectomy and prostatectomy were identified in the American College of Surgeons National Surgical Quality Improvement Program database. Non-parsimonious propensity score methods were used to construct procedure-specific matched-pair cohorts that reduced baseline differences between patients who underwent MIS and those who did not. Bonferroni correction for multiple comparisons was applied and P < 0·006 was considered significant.

Results

Of the 532 287 patients identified, 53·8 per cent underwent MIS. Propensity score matching yielded an overall sample of 327 736 patients (appendicectomy 46 688, colectomy 152 114, inguinal hernia repair 59 066, hysterectomy 59 066, prostatectomy 10 802). Within the procedure-specific matched pairs, MIS was associated with significantly lower odds of Clavien–Dindo grade I–II, III and IV complications (P ≤ 0·004), unplanned readmissions (P < 0·001) and reduced hospital stay (P < 0·001) in four of the five procedures studied, with the exception of inguinal hernia repair. The odds of death were lower in patients undergoing MIS colectomy (P < 0·001), hysterectomy (P = 0·002) and appendicectomy (P = 0·002).

Conclusion

MIS was associated with significantly fewer 30-day postoperative complications, unplanned readmissions and deaths, as well as shorter hospital stay, in patients undergoing colectomy, prostatectomy, hysterectomy or appendicectomy. No benefits were noted for inguinal hernia repair.
One-year results of the SCANDIV randomized clinical trial of laparoscopic lavage versus primary resection for acute perforated diverticulitis
Authors:   SCANDIV Study Group, Schultz J K , Wallon C , Blecic L , Forsmo H M , Folkesson J , Buchwald P , Kørner H , Dahl F A , Øresland T , Yaqub S , Papp A , Ersson U , Zittel T , Fagerström N , Gustafsson D , Dafnis G , Cornelius M , Egenvall M , Nyström P O , Syk I , Vilhjalmsson D , Arbman G , Chabok A , Helgeland M , Bondi J , Husby A , Helander R , Kjos A , Gregussen H , Talabani A J , Tranø G , Nygaard I H , Wiedswang G , Sjo O H , Desserud K F , Norderval S , Gran M V , Pettersen T , Sæther A
Published: June 2017

Background

Recent randomized trials demonstrated that laparoscopic lavage compared with resection for Hinchey III perforated diverticulitis was associated with similar mortality, less stoma formation but a higher rate of early reintervention. The aim of this study was to compare 1-year outcomes in patients who participated in the randomized Scandinavian Diverticulitis (SCANDIV) trial.

Methods

Between February 2010 and June 2014, patients from 21 hospitals in Norway and Sweden presenting with suspected perforated diverticulitis were enrolled in a multicentre RCT comparing laparoscopic lavage and sigmoid resection. All patients with perforated diverticulitis confirmed during surgery were included in a modified intention-to-treat analysis of 1-year results.

Results

Of 199 enrolled patients, 101 were assigned randomly to laparoscopic lavage and 98 to colonic resection. Perforated diverticulitis was confirmed at the time of surgery in 89 and 83 patients respectively. Within 1 year after surgery, neither severe complications (34 versus 27 per cent; P = 0·323) nor disease-related mortality (12 versus 11 per cent) differed significantly between the lavage and surgery groups. Among the 144 patients with purulent peritonitis, the rate of severe complications (27 per cent (20 of 74) versus 21 per cent (15 of 70) respectively; P = 0·445) and disease-related mortality (8 versus 9 per cent) were similar. Laparoscopic lavage was associated with more deep surgical-site infections (32 versus 13 per cent; P = 0·006) but fewer superficial surgical-site infections (1 versus 17 per cent; P = 0·001). More patients in the lavage group underwent unplanned reoperations (27 versus 10 per cent; P = 0·010). Including stoma reversals, a similar proportion of patients required a secondary operation (28 versus 29 per cent). The stoma rate at 1 year was lower in the lavage group (14 versus 42 per cent in the resection group; P < 0·001); however, the Cleveland Global Quality of Life score did not differ between groups.

Conclusion

The advantages of laparoscopic lavage should be weighed against the risk of secondary intervention (if sepsis is unresolved). Assessment to exclude malignancy (although uncommon) is advised. Registration number: NCT01047462 (http://www.clinicaltrials.gov).
Three‐dimensional orientation of the acetabulum
Authors: Suzuki Daisuke , Nagoya Satoshi , Takashima Hiroyuki , Tateda Kenji , Yamashita Toshihiko
Published: June 2017

This study was designed specifically to determine the normal acetabular orientation and femoral head covering, and whether these are affected by age or sex. Computed tomographic images of normal Japanese hip joints were used (males 60, females 60; mean age 48.3 years, range 15–79 years). Male and female age profiles were matched. The reconstructed 3‐D pelvic images were aligned in the anatomical pelvic coordinate system. The acetabular orientation angles and femoral covering angles were measured in the sagittal, coronal, and horizontal planes. In the sagittal plane, the acetabular orientation angle was operative anteversion (O‐av), and the femoral covering angles were the anterior and posterior center‐edge angles (ACE and PCE). In the coronal plane, they were the Sharp angle (SA) and the lateral center‐edge angle (LCE). In the horizontal plane, they were anatomical anteversion (A‐av) and the anterior and posterior sector angles (ASA and PSA). The O‐av, SA, and A‐av were smaller in the male than the female acetabulum (P < 0.01). SA in both males and females was inversely correlated with age (P < 0.01). Both male PCE and PSA were significantly smaller than those of females, while male ASA was larger than female ASA (P < 0.05). The male acetabulum is directed further outward and downward than the female one. However, this does not indicate that the male acetabulum covers the femoral head more, because there is no significant sex difference in the LCE. Femoral coverage is more posteriorly biased in females than in males owing to pelvic inclination. Clin. Anat. 30:753–760, 2017. © 2017Wiley Periodicals, Inc.
The Interaction Mode of Groove Binding Between Quercetin and Calf Thymus DNA Based on Spectrometry and Simulation
Authors: Sha Yijie , Chen Xu , Niu Bing , Chen Qin
Published: June 2017

Quercetin, a ubiquitous flavanoid, has numerous pharmacological effects, such as antioxidant and antitumor. Previous studies showed nucleic acids were the potential biological targets for antitumor medicine. For exploring the mechanism of DNA‐target medicine, the interaction between quercetin and calf thymus DNA was studied based on the method of spectrometry and simulation in our study. Firstly, the interaction between quercetin and calf thymus DNA was confirmed by fluorescence spectrometry. Furthermore, circular dichroism, fluorescence polarization, competitive displacement assay, and salt concentration dependence assay were applied to search the interaction mode of quercetin‐calf thymus DNA, which proved the existence of groove binding and electrostatic interaction. Meanwhile, quenching constant Ksv, binding constant Ka and the number of binding sites n was calculated, inferring that the fluorescence quenching occurred by static quenching process, and the main acting force was hydrogen bond. Finally, molecular docking was used to simulate and analyze the interaction between quercetin and calf thymus DNA.
SNAP‐Tag‐Based Subcellular Protein Labeling and Fluorescent Imaging with Naphthalimides
Authors: Wang Chao , Song Xinbo , Xiao Yi
Published: June 2017

Genetically encoded technologies provide methods for the specific labeling and imaging of proteins, which is essential to understand the subcellular localization of these proteins and their function. Herein, we employed naphthalimide, an efficient two‐photon fluorophore, to develop O6‐benzylguanine (BG) derivatives for specific labeling of subcellular proteins and fluorescent imaging through the SNAP‐tag. Three naphthalimide–BG derivatives, TNI‐BG, QNI‐BG, and ONI‐BG, were conveniently synthesized through modular “click chemistry” in high yields. All of them showed high labeling efficiency with SNAP‐tag in solution (≈1–2×103 s−1 m−1) and in bacteria. Among them, ONI‐BG showed high specificity to diffused, histone H2B and mitochondria COX8A targeted SNAP‐tag in mammalian cells. The protein‐labeled naphthalimides exhibited high two‐photon absorption cross‐sections, which indicated their potential application in protein‐specific two‐photon fluorescent imaging, such as two‐photon fluorescent lifetime imaging and two‐photon multicolor imaging. Therefore, ONI‐BG is a versatile tool that can be used to track subcellular proteins through multiple fluorescent techniques.
Tuning Sulfur Oxidation States on Thioether‐Bridged Peptide Macrocycles for Modulation of Protein Interactions
Authors: Perell Gabriella T. , Staebell Rachel Lynn , Hairani Mehrdad , Cembran Alessandro , Pomerantz William C. K.
Published: June 2017

Thioethers, sulfoxides, and sulfonium ions, despite diverse physicochemical properties, all engage in noncovalent interactions with proteins. Thioether‐containing macrocycles are also attracting attention as protein–protein interaction (PPI) inhibitors. Here, we used a model PPI between α‐helical mixed lineage leukemia (MLL) protein and kinase‐inducible domain interacting (KIX) domain to evaluate oxidation effects on sulfurcontaining macrocycle structure, stability, and protein affinity. Desolvation effects from various polarity states were evaluated computationally and experimentally at the side chain, amino acid, and peptide level. Sulfur‐containing side chains spanned polarity ranges between all‐hydrocarbon and lactam bridges for modulating solubility, cellular uptake, and affinity. Helical propensity studies showed that, although oxidized sulfur‐containing side chains could be tolerated, conformational effects were sequence‐dependent. In some cases, proteolytic stability, binding capacity with KIX, and increased helicity were obtained as first steps toward developing PPI inhibitors.
Modeling of HILIC retention behavior with theoretical models and new spline interpolation technique
Authors: Tumpa Anja , Mišković Stefan , Stanimirović Zorica , Jančić‐Stojanović Biljana , Medenica Mirjana
Published: June 2017

When it is taken into account that hydrophilic interaction liquid chromatography (HILIC) as an analytical method is relatively young compared with the other techniques, retention modeling could still bring scientifically valuable data to the field. Therefore, in this paper, olanzapine and its 8 impurities were selected as a test mixture, considering that they have never been analyzed in HILIC before. Their investigation on 4 different HILIC columns (bare silica, cyanopropyl, diol and zwitterionic) has been performed. The mixture of 9 structurally similar substances allows the examination of complex HILIC retention behavior depending on the chemical properties of the analytes, as well as of the stationary phase. To describe the nature of the relationship between the retention and the stronger eluent content in the mobile phase, we fitted experimentally obtained data to several theoretical (localized adsorption, nonlocalized partition, quadratic, and mixed) models. Results show that the best fit is the quadratic model with the highest R2 and cross‐validated coefficient of determination (Q2) values, but its usage has some drawbacks. With the aim to improve the possibility to predict retention behavior in HILIC, a new empirical model was proposed. For that purpose, a spline interpolation technique was performed, by dividing the experimental range into several subdivisions. This type of interpolation was performed for the first time in the chromatographic field. The estimation of the polynomial equations was performed using Q2 values. Obtained Q2 values pointed out the goodness of fit of the model, as well as its good predictive capabilities. In the end, the prediction capabilities were experimentally verified, under randomly chosen conditions from the experimental range. The errors in prediction were all under 10%, which is satisfying for HILIC.
Weighted time series fault diagnosis based on a stacked sparse autoencoder
Authors: Lv Feiya , Wen Chenglin , Liu Meiqin , Bao Zhejing
Published: June 2017

Most statistical analysis technologies use detection thresholds for fault diagnosis, which often cannot effectively characterize some specific faults in a statistical manner. However, the details and small changes in the faults can be exploited by deep learning‐based feature representation. In this paper, we present a weighted time series fault diagnosis method to learn the deep correlations of faults and reduce the loss of fault information. Our model includes 2 key novel properties: (1) It can learn high‐level abstract features of faults and the underlying fault patterns, which is particularly efficient for detecting incipient faults; (2) a mathematical framework of stacked sparse autoencoder‐based fault diagnosis, with capabilities of multiple nonlinear mapping and complex function approximation, is presented. The monitoring performance was compared with multivariate statistical methods and conventional artificial intelligence methods on the Tennessee Eastman process data set, which is a well‐known chemical industrial benchmark. The experimental results showed its performance gain over existing methods, especially for incipient faults that are difficult to detect with traditional technologies.
Conjunction of Pyrrole and Amide Moieties: Highly Anion‐Responsive π‐Electronic Molecules Forming Ion‐Free and Ion‐Pairing Assemblies
Authors: Kuno Atsuko , Tohnai Norimitsu , Yasuda Nobuhiro , Maeda Hiromitsu
Published: June 2017

Dipyrrolyldiketone BF2 complexes with amide units at pyrrole α‐positions were synthesized in modest yields and showed extremely high anion‐binding affinities because of multiple hydrogen‐bonding interactions. The phenyl‐amide‐substituted derivative formed solid‐state chiral helical structures, wherein π planes were oriented parallel to the helical directions. Examination of anion‐binding behavior using 1H NMR spectroscopy combined with theoretical studies suggested fast pyrrole inversions, particularly for the phenyl‐amide‐substituted derivative. The anion complexes behaved as building units of ion‐pairing assemblies in combination with planar and bulky cations.
Silver(I) Clusters with Carba‐closo‐dodecaboranylethynyl Ligands: Synthesis, Structure, and Phosphorescence
Authors: Hailmann Michael , Wolf Natalia , Renner Rebecca , Hupp Benjamin , Steffen Andreas , Finze Maik
Published: June 2017

Salts of anionic silver(I) clusters with the carba‐closo‐dodecaboranylethynyl ligand were obtained from {Ag2(12‐C≡C‐closo‐1‐CB11H11)}n, selected pyridines, and [Et4N]Cl or [Ph4P]Br. Salts of octahedral silver(I) clusters [Et4N]2[Ag6(12‐C≡C‐closo‐1‐CB11H11)4(4‐X‐C5H5N)x] were formed with pyridine (X=H, x=8), 4‐methylpyridine (X=Me, x=8), and 4‐cyanopyridine (X=CN, x=10). In contrast, 3,5‐lutidine (3,5‐Me2Py) did not result in salts of dianionic clusters, even in the presence of excess of [Et4N]Cl or [Ph4P]Br; instead salts of monoanionic AgI7 clusters, [Et4N][Ag7(12‐C≡C‐closo‐1‐CB11H11)4(3,5‐Me2Py)9] and [Ph4P][Ag7(12‐C≡C‐closo‐1‐CB11H11)4(3,5‐Me2Py)13] were obtained. The AgI7 cluster is pentagonal bipyramidal in the former, but is an edge‐capped octahedron in the latter. The 4‐methylpyridine and 3,5‐lutidine complexes show green phosphorescence at room temperature. Although argentophilic interactions give rise to sufficient spin–orbit coupling for intersystem crossing S1→Tn and moderate‐to‐high radiative rate constants, time‐resolved measurements indicate that the quantum yields are greatly influenced by the pyridine ligands, which mainly determine the non‐radiative rate constants. In addition, the crystal structures of [Ag16(12‐C≡C‐closo‐1‐CB11H11)8(Py)9.25(CH3CN)2(CH2Cl2)0.75]⋅CH2Cl2, [Ag8(12‐C≡C‐closo‐1‐CB11H11)4(Py)12], [Ag10(12‐C≡C‐closo‐1‐CB11H11)4(4‐MePy)10Br2], [Ag7(12‐C≡C‐closo‐1‐CB11H11)3(4‐tBuPy)11Cl]⋅(4‐tBuPy), and [Ag9(12‐C≡C‐closo‐1‐CB11H11)4(3,5‐Me2Py)11Cl] were elucidated.
A Photo‐Crosslinkable Biotin Derivative of the Phosphoantigen (E)‐4‐Hydroxy‐3‐Methylbut‐2‐Enyl Diphosphate (HMBPP) Activates Vγ9Vδ2 T Cells and Binds to the HMBPP Site of BTN3A1
Authors: Mattarei Andrea , Enzinger Monika , Gu Siyi , Karunakaran Mohindar Murugesh , Kimmel Brigitte , Berner Nicole , Adams Erin J. , Herrmann Thomas , Amslinger Sabine
Published: June 2017

Vγ9Vδ2 T cells play an important role in the cross talk of the innate and adaptive immune system. For their activation by phosphoantigens (PAgs), both cell surface receptors, the eponymous Vγ9Vδ2 T cell antigen receptors (Vγ9Vδ2 TCRs) on Vγ9Vδ2 T cells and butyrophilin 3A1 (BTN3A1) on the phosphoantigen‐“presenting” cell, are mandatory. To find yet undetected but further contributing proteins, a biotinylated, photo‐crosslinkable benzophenone probe BioBP‐HMBPP (2) was synthesized from a known allyl alcohol in nine steps and overall 16 % yield. 2 is based on the picomolar PAg (E)‐4‐hydroxy‐3‐methylbut‐2‐enyl diphosphate (HMBPP, 1). Laser irradiation of 2 at 308 nm initiated the photo‐crosslinking reaction with proteins. When the B30.2 domain of BTN3A1, which contains a positively charged PAg‐binding pocket, was exposed to increasing amounts of HMBPP (1), labeling by BioBP‐HMBPP (2) was reduced significantly. Because BSA labeling was not impaired, 2 clearly binds to the same site as natural ligand 1. Thus, BioBP‐HMBPP (2) is a suitable tool to identify co‐ligands or receptors involved in PAg‐mediated T cell activation.
Polar Intermetallics Pr5Co2Ge3 and Pr7Co2Ge4 with Planar Hydrocarbon‐Like Metal Clusters
Authors: Lin Qisheng , Aguirre Kaiser , Saunders Scott M. , Hackett Timothy A. , Liu Yong , Taufour Valentin , Paudyal Durga , Budko Sergey , Canfield Paul C. , Miller Gordon J.
Published: June 2017

Planar hydrocarbon‐like metal clusters may foster new insights linking organic molecules with conjugated π–π bonding interactions and inorganic structures in terms of their bonding characteristics. However, such clusters are uncommon in polar intermetallics. Herein, we report two polar intermetallic phases, Pr5Co2Ge3 and Pr7Co2Ge4, both of which feature such planar metal clusters, namely, ethylene‐like [Co2Ge4] clusters plus the concatenated forms and polyacene‐like [Co2Ge2]n ribbons in Pr5Co2Ge3, and 1,2,4,5‐tetramethylbenzene‐like [Co4Ge6] cluster in Pr7Co2Ge4. Just as in the related planar organic structures, these metal–metalloid species are dominated by covalent bonding interactions. Both compounds magnetically order at low temperature with net ferromagnetic components: Pr5Co2Ge3 through a series of transitions below 150 K and Pr7Co2Ge4 through a single ferromagnetic transition at 19 K. Spin‐polarized electronic structure calculations for Pr7Co2Ge4 reveal strong spin‐orbit coupling within Pr and considerable magnetic contributions from Co atoms. This work suggests that similar structural chemistry can emerge for other rare‐earth/late‐transition‐metal/main‐group systems.
Towards a multilayered permission‐based access control for extending Android security
Authors: Chang Rui , Jiang Liehui , Chen Wenzhi , He Hongqi , Yang Shuiqiao , Jiang Hang , Liu Wei , Liu Yong
Published: June 2017

This paper discusses security issues on the user equipment, which is the “last mile” of social networks. One of the main Achilles' heel of social networks is not the organization of networks themselves, but the user devices, typically Android ones. The existing system of privileges makes it easy to infiltrate the network via applications installed on users' devices. Conventional signature‐based and static analysis methods are vulnerable. Access to privacy‐ and security‐relevant parts of the application programming interface is controlled by the corresponding permission in a manifest file. While requesting access to permissions, it may offer opportunities to malicious codes, which will cause security issues. Few works among permission analysis, however, pay attention to the prevention of permission leakage on both hardware and software frameworks. In this paper we tackle the challenge of providing our multilayered permission‐based security extension scheme on Android platforms. We propose a usage and access control model and an effective method of preventing permission leakage based on ARM TrustZone security extension mechanism. In contrast to previous work, the proposed security architecture provides a permission‐based mandatory access control on Android middleware, Linux kernel, and hardware layers. The evaluation results demonstrate the effectiveness of the proposed scheme in mitigating permission leakage vulnerabilities.
A QoC‐based model for performance and QoE trade‐off in distributed systems
Authors: D'Amato André , Dantas Mario
Published: June 2017

This paper proposes a quality of context (QoC)–based model to enhance trade‐off between system performance and users quality of experience (QoE) in distributed systems. The QoE considers the users subjective perceptions of quality on technology services and depends on context attributes related to the users expectations. In addition, context information can be used to improve performance in context‐aware systems. Therefore, the QoC‐based model proposed in this paper aims to establish performance and QoE trade‐off for resource allocation in distributed systems. With the massive data growth over the past years, the demand for computing capacity has been notably growing in a proportional way. In view of that, the demand for distributed systems has also increased significantly due to the advantages of distributed computing such as cost‐benefit gains, large processing capacity, and an extensive capability for resources sharing. In this sense, the large‐scale utilization of distributed systems has generated problems concerning resource allocation because of the heterogeneous characteristics and continuous evolution of distributed computational devices, resulting in several challenges in terms of environment performance and users' satisfaction trade‐off. The model conceived in this paper provides for an experimental evaluation considering performance and QoE trade‐off by means of simulations. Simulations were performed in order to study complex distributed systems scenarios. Experimental results showed that the proposed QoC model policy has an enhanced performance in comparison with classical approaches.
CCHybrid: CPU co‐scheduling in virtualization environment
Authors: Yu Linchen
Published: June 2017

Virtualization is very important to build the emerging cloud infrastructure, and a VM (virtual machine) with many kinds of workloads can run on physical machines in cloud environment. The VMM (virtual machine manager) scheduling algorithm asynchronously schedules each VCPU (virtual CPU) of a VM and ensures the CPU time usage of each VM. This proportional share method is widely used, because it simplifies the implementation of VMM CPU scheduling algorithm and can provide near‐perfect performance for most ordinary workloads. However, when a VM runs with parallel workloads, the above method causes performance degradation because of the negative impact of virtualized systems. Therefore, in this paper, we propose an optimized scheduling system, called CCHybrid, for parallel program in the Xen. It uses weight‐based proportion share strategy to ensure the fairness. In order to resolve the impact of virtualization on synchronization, it uses a novel co‐scheduling strategy, which dynamically adjusts the size of co‐scheduling to remit CPU fragmentation and maintains the original asynchronous scheduling policy for non‐parallel applications. In this way, CCHybrid provides CPU resource allocation services for Xen and can decrease the negative impact of virtualized systems, while ensuring the fairness of VMs and the performance of non‐parallel workload. Experimental results show that in the case of multiple VMs, CCHybrid improves the performance of parallel workload from 15% to 50%, and the impact on non‐parallel workload is less than 5%, in comparison with the credit scheduling algorithm of Xen.
Chemical Communication between Molecules
Authors: Remón Patricia , Pischel Uwe
Published: June 2017

In this Minireview conceptual approaches towards the communication between (supra)molecular species are illustrated. The reviewed mechanisms include photophysical communication through energy transfer and communication mediated by chemical species that are released from precursors upon application of an external stimulus. The focus is on the stimulation by (reversible) photoreactions. Special attention has been given to supramolecular systems that illustrate the idea of chemical communication and information transfer in a very descriptive manner.
The IL–10/STAT3 axis: Contributions to immune tolerance by thymus and peripherally derived regulatory T‐cells
Authors: Schmetterer Klaus G. , Pickl Winfried F.
Published: June 2017

The signal transducer and activator of transcription (STAT) proteins are important mediators for the integration of extrinsic signals provided by cytokines and hormones and thereby adapt cellular processes to their surroundings. In the past decade, the involvement of STAT3 in the regulation of T‐cell responses has become a topic of increasing interest. STAT3 is activated in response to multiple cytokines, many of which have been shown to influence T‐cell responses. Interestingly, many of these factors have been described with apparent opposing roles, such as the highly pro–inflammatory potency of IL–6 and the anti–inflammatory properties of IL–10, thus raising the possibility that STAT3 signaling may fulfill diverse roles in CD4+ T‐cells. Here, we review the contribution of STAT3 to the induction and function of both peripherally induced as well as thymus‐derived regulatory T‐cells. Indeed, experimental approaches as well as studies of human patients suffering from e.g. Job's (hyper IgE) syndrome or inflammatory bowel disease (IBD) have now established a clear–cut role for the IL–10/STAT3 axis in immune tolerance; further understanding of these processes could lead to novel therapeutic approaches for autoimmune diseases.
Development of Albumin‐closo‐Dodecaborate Conjugates as Boron Carriers for Neutron‐Capture Therapy by Ru(bpy)3‐Photocatalyzed Modification of Tyrosine
Authors: Sato Shinichi , Ishii Satomu , Nakamura Hiroyuki
Published: June 2017

Serum albumin has attracted significant attention as a drug‐delivery carrier to tumor tissue. We previously reported boron neutron capture therapy (BNCT), an effective method that uses maleimide‐functionalized closo‐dodecaborate albumin conjugates (MID‐ACs). MID can form covalent bonds with the free thiol group of Cys34 and with lysine residues in albumin. In this study, we synthesized tyrosyl‐radical‐trapping‐moiety‐functionalized closo‐dodecaborates (TRT‐DBs), which were expected to form covalent bonds with tyrosine residues. N′‐Acetyl‐N,N‐dimethylphenylenediamine was chosen as the TRT moiety to bind to closo‐dodecaborate through an amide linker (TRT‐DB 1) and an ammonium linker (TRT‐DB 2). TRT‐DB 1 more efficiently conjugated to bovine serum albumin (BSA) than 2: approximately 2.4 molecules of 1 were bound to each BSA if BSA (10 µm) was treated with 1 (1 mm) in the presence of Ru(bpy)3 (1 mm; bpy = 2,2′‐bipyridyl) and ammonium persulfate (1 mm) under light irradiation for 1 min. Furthermore, double modification of BSA with 1 and MID increased the boron density in BSA for efficient boron delivery to tumors. Western blot analysis using the anti‐B12 cluster antibody revealed that closo‐dodecaborate‐conjugated BSAs were taken up by colon 26 cells.
Inherently Chiral Calix[4]arenes: A Chiral Sulfoxide as an Ortholithiation Director
Authors: Castell Dominic C. , Lesotho Ntlama , Nikolayenko Varvara I. , Arnott Gareth E.
Published: June 2017

In pursuit of nonracemic, inherently chiral calix[4]arenes, we describe herein the application of a chiral tert‐butyl sulfoxide in asymmetrically directing ortholithiation on a calix[4]arene. We demonstrate good diastereoselectivity (dr = 95:5) in the reaction, and also provide proof of the major diastereomer through single‐crystal X‐ray diffraction.
Palladium‐Catalyzed Carbonylative Synthesis of Amides from Aryltriazenes under Additive‐Free Conditions
Authors: Yin Zhiping , Wang Zechao , Wu Xiao‐Feng
Published: June 2017

An interesting palladium‐catalyzed carbonylative synthesis of amides from aryltriazenes was developed. By using Pd(MeCN2)Cl2 as the catalyst precursor under CO pressure through a N2 extrusion/CO insertion sequence, a broad range of aryltriazenes were transformed into the corresponding amides in good yields with excellent functional group tolerance. Remarkably, no additives such as acids or phosphine ligands were required.
Multivariate Calibration Transfer between two Potentiometric Multisensor Systems
Authors: Khaydukova Maria , Panchuk Vitaly , Kirsanov Dmitry , Legin Andrey
Published: June 2017

A multivariate calibration of multisensor systems is a very important stage in their application. Construction of reliable calibration model requires significant investment of time and money. Once established, calibration model can be applied normally only together with that particular multisensor system, which was employed for its’ construction – this can be a serious limitation for a wide adoption of multisensor systems in common laboratory practice. In order to address this issue we have studied the applicability of several calibration transfer techniques, such as direct standardization, single wavelength standardization and standardization with regularization coefficient for the data obtained from two potentiometric multisensor systems in analysis of complex lanthanide mixtures. It was found that mathematical correction of sensor array response using standardization with regularization coefficient allows for using the regression model derived for one sensor array together with the data obtained from another sensor array. The value of root mean squared error of prediction for total lanthanide concentration increased insignificantly (0.10 instead of 0.07 in log scale) compared with that provided by the first multisensor system.
Tools to minimize interlaboratory variability in vitellogenin gene expression monitoring programs
Authors: Jastrow Aaron , Gordon Denise A. , Auger Kasie M. , Punska Elizabeth C. , Arcaro Kathleen F. , Keteles Kristen , Winkelman Dana , Lattier David , Biales Adam , Lazorchak James M.
Published: June 2017

The egg yolk precursor protein vitellogenin is widely used as a biomarker of estrogen exposure in male fish. However, standardized methodology is lacking and little is known regarding the reproducibility of results among laboratories using different equipment, reagents, protocols, and data analysis programs. To address this data gap we tested the reproducibility across laboratories to evaluate vitellogenin gene (vtg) expression and assessed the value of using a freely available software data analysis program. Samples collected from studies of male fathead minnows (Pimephales promelas) exposed to 17α-ethinylestradiol (EE2) and minnows exposed to processed wastewater effluent were evaluated for vtg expression in 4 laboratories. Our results indicate reasonable consistency among laboratories if the free software for expression analysis LinRegPCR is used, with 3 of 4 laboratories detecting vtg in fish exposed to 5 ng/L EE2 (n = 5). All 4 laboratories detected significantly increased vtg levels in 15 male fish exposed to wastewater effluent compared with 15 male fish held in a control stream. Finally, we were able to determine that the source of high interlaboratory variability from complementary deoxyribonucleic acid (cDNA) to quantitative polymerase chain reaction (qPCR) analyses was the expression analysis software unique to each real-time qPCR machine. We successfully eliminated the interlaboratory variability by reanalyzing raw fluorescence data with independent freeware, which yielded cycle thresholds and polymerase chain reaction (PCR) efficiencies that calculated results independently of proprietary software. Our results suggest that laboratories engaged in monitoring programs should validate their PCR protocols and analyze their gene expression data following the guidelines established in the present study for all gene expression biomarkers. Environ Toxicol Chem 2017;36:3102–3107. Published 2017 Wiley Periodicals Inc. on behalf of SETAC. This article is a US government work and, as such, is in the public domain in the United States of America.
Natural variability of biochemical biomarkers in the macro-zoobenthos: Dependence on life stage and environmental factors
Authors: Scarduelli Lucia , Giacchini Roberto , Parenti Paolo , Migliorati Sonia , Di Brisco Agnese Maria , Vighi Marco
Published: June 2017

Biomarkers are widely used in ecotoxicology as indicators of exposure to toxicants. However, their ability to provide ecologically relevant information remains controversial. One of the major problems is understanding whether the measured responses are determined by stress factors or lie within the natural variability range. In a previous work, the natural variability of enzymatic levels in invertebrates sampled in pristine rivers was proven to be relevant across both space and time. In the present study, the experimental design was improved by considering different life stages of the selected taxa and by measuring more environmental parameters. The experimental design considered sampling sites in 2 different rivers, 8 sampling dates covering the whole seasonal cycle, 4 species from 3 different taxonomic groups (Plecoptera, Perla grandis; Ephemeroptera, Baetis alpinus and Epeorus alpicula; Tricoptera, Hydropsyche pellucidula), different life stages for each species, and 4 enzymes (acetylcholinesterase, glutathione S-transferase, alkaline phosphatase, and catalase). Biomarker levels were related to environmental (physicochemical) parameters to verify any kind of dependence. Data were statistically elaborated using hierarchical multilevel Bayesian models. Natural variability was found to be relevant across both space and time. The results of the present study proved that care should be paid when interpreting biomarker results. Further research is needed to better understand the dependence of the natural variability on environmental parameters. Environ Toxicol Chem 2017;36:3158–3167. © 2017 SETAC
Aging of zinc added to soils with a wide range of different properties: Factors and modeling
Authors: Zhang Xi , Jiang Bao , Ma Yibing
Published: June 2017

The aging of metals added to soil is significant in ecological risk assessment and the derivation of soil environmental quality criteria. Semimechanistic aging models have been developed for some metals, but not for zinc (Zn). In the present study, a published dataset detailing the changes in isotopic exchangeability with time, after water-soluble Zn was added to 23 soils and incubated for 813 d, was used to analyze the effect of soil properties on aging and develop empirical and mechanistic models. Aging was mainly controlled by soil pH, probably because of precipitation, and was linearly correlated with the square root of incubation time, probably as a result of diffusion. Based on precipitation, diffusion, and/or occlusion, semimechanistic aging models were developed using a Zn hydrolysis constant of 6.52 to 6.61, apparent diffusion rate coefficient (D/r2) of 1.41 × 10−5/d, and a root mean square error of less than 15%. The optimized models were accurately validated by 4 independent field-incubated soils, with different doses of Zn under different conditions (the differences between measured and predicted isotopically exchangeable Zn were less than 10%). This enabled an understanding of the long-term behavior of Zn added to soils, and the results can be used for environmental risk assessments and the normalization of ecotoxicity datasets in the derivation of soil environmental quality criteria. Environ Toxicol Chem 2017;36:2925–2933. © 2017 SETAC
Surveillance and early warning systems of infectious disease in China: From 2012 to 2014
Authors: Zhang Honglong , Wang Liping , Lai Shengjie , Li Zhongjie , Sun Qiao , Zhang Peng
Published: June 2017

Appropriate surveillance and early warning of infectious diseases have very useful roles in disease control and prevention. In 2004, China established the National Notifiable Infectious Disease Surveillance System and the Public Health Emergency Event Surveillance System to report disease surveillance and events on the basis of data sources from the National Notifiable Infectious Disease Surveillance System, China Infectious Disease Automated‐alert and Response System in this country. This study provided a descriptive summary and a data analysis, from 2012 to 2014, of these 3 key surveillance and early warning systems of infectious disease in China with the intent to provide suggestions for system improvement and perfection.