bluuebunny/crossref_metadata_2025 huggingface dataset:
Descending necrotizing mediastinitis: 5 years of published data in Japan
Authors: Sumi Yuka
Published: June 2014

Descending necrotizing mediastinitis implies infection originating from the neck, most commonly an oropharyngeal or odontogenic focus, that spreads in the cervical fascial spaces and descends into the mediastinum. Early diagnosis is essential because descending necrotizing mediastinitis can rapidly progress to septic shock and organ failure. A comprehensive review of the current data of descending necrotizing mediastinitis in Japan was carried out using PubMed and ICHUSHI from the last 5 years. The symptoms, origins, comorbid conditions, treatment modalities, complications, and survival rates were analyzed. Tonsillar and pharyngeal origin was more identified compared to odontogenic origin. More than one‐third of patients were diabetic and 28% of them were not identified as having any comorbidity. Streptococcus sp. and anaerobes were most isolated, reflecting the microflora of the oral cavity. Of the broad antibiotics, carbapenem was the most used as treatment, and clindamycin was the most co‐given. Mediastinal drainage approach varied widely and the optimal approach is controversial. Twenty‐one patients were treated with video‐assisted thoracic surgical drainage and 15 cases by percutaneous catheter drainage, whereas transcervical approach was applied in 25 patients and thoracotomy was carried out in 21 patients. The overall mortality was 5.6%. Many authors advocated that the most effective management tool is a high degree of clinical suspicion followed by prompt and adequate drainage with intensive care including hemodynamic and nutritional support and repeat computer tomographic monitoring.
Cotton fibers reinforcement of HNBR: Control of fiber alignment and its influence on properties of HNBR vulcanizates
Authors: Sanprasert Pimsaruta , Sombatsompop Narongrit , Sae‐oui Pongdhorn , Sirisinha Chakrit
Published: June 2014

This article focuses on the reinforcement of hydrogenated acrylonitrile butadiene rubber (HNBR) by cotton fiber as natural reinforcing filler. The effect of fiber alignment on the properties of HNBR compounds and vulcanizates is investigated. Properties of interest include rheological behavior, cure, tensile, abrasion, and dynamic mechanical properties which are correlated to the magnitudes of state‐of‐mix, bound rubber content, crosslink density and fiber alignment. Results obtained reveal that mechanical properties of rubber composites are improved dramatically by the addition of cotton fiber due to the enhanced hydrodynamic effect in association with crosslink density. Furthermore, the degree of fiber alignment is found to depend strongly on shear strain. The results demonstrate the importance of fiber alignment controlled efficiently by shear strain. © 2014 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2014, 131, 41090.
Design of cyanate ester/azomethine/ZrO2 nanocomposites high‐k dielectric materials by single step sol–gel approach
Authors: Ariraman Mathivathanan , kumar Ramachandran Sasi , Alagar Muthukaruppan
Published: June 2014

In this article we designed a cyanate ester based novel hybrid nanocomposites by sol–gel approach with different weight percentages of Zirconium dioxide (ZrO2). The synthesized monomer and polymer nanocomposites were characterized by Fourier‐transform infrared, 1H, and 13C nuclear magnetic resonance (NMR) spectra. Optical and thermal properties reveals the excellent optical transparency and good thermal stability of hybrid nanocomposites. Scanning electron microscope and high resolution transmission electron microscope analysis confirm the homogeneous dispersion of ZrO2 in the nanocomposites. Interestingly 7% ZrO2 nanocomposite exhibit highest k value of 9.21 which may be due to the well dispersion of ZrO2 and their strong interfacial polarization in the organic–inorganic hybrid nanocomposites. © 2014 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2014, 131, 41097.
Evaluation of photovoltaic efficiency of dye‐sensitized solar cells fabricated with electrospun PVDF‐PAN‐Fe2O3 composite membrane
Authors: Sethupathy Malaisamy , Pandey Priyanka , Manisankar Paramasivam
Published: June 2014

Poly(vinylidene fluoride)‐polyacrylonitrile‐based membranes containing Fe2O3 nanoparticles were prepared by electrospinning technique and characterized by HR‐SEM, FTIR, and XRD analysis. The effect of electrolyte in the electrospun nanofibers on electrolyte uptake, ionic conductivity and porosity were studied. The electrospun membranes containing Fe2O3 showed an enhanced ionic conductivity than that of without Fe2O3. Among the prepared membranes, the membrane with 7 wt % Fe2O3 has the highest liquid electrolyte uptake of 562% and ionic conductivity of 6.81 × 10−2 S cm−1. The photovoltaic performance for open circuit voltage (Voc), Short‐circuit current density (Jsc), Fill factor (FF), and η of the DSSC fabricated with 7 wt % Fe2O3 are 0.77 V, 10.4 mA/cm2, 0.62 and 4.9%, respectively. © 2014 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2014, 131, 41107.
Cetacean occurrence, habitat preferences and potential for cetacean–fishery interactions in Iberian Atlantic waters: results from cooperative research involving local stakeholders
Authors: Goetz Sabine , Read Fiona L. , Ferreira Marisa , Portela Julio Martínez , Santos Maria Begoña , Vingada José , Siebert Ursula , Marçalo Ana , Santos Jorge , Araújo Hélder , Monteiro Silvia , Caldas Mara , Riera Marcos , Pierce Graham J.
Published: June 2014

Iberian Atlantic waters are heavily exploited by Spanish and Portuguese fisheries. Overlaps between fishery target species and cetacean diet, and between fishing grounds and cetacean foraging areas, can lead to cetacean–fishery interactions including bycatch mortality of cetaceans.

The present study assesses cetacean distribution, habitat preferences and hotspots for cetacean–fishery interactions by using a cooperative research approach with stakeholder participation (fishers, fisheries observers, fisheries authorities, scientists), as well as the combination of different opportunistic data sources (interviews, on‐board observations). The usefulness of each data type is evaluated. The implications of results for the monitoring and mitigation of cetacean–fishery interactions are discussed.

Generalized linear models and GIS maps were used to relate cetacean occurrence patterns to environmental variables (geographic area, water depth, coastal morphology) and to fishing activities (fishing grounds, fisheries target species).

Common and bottlenose dolphins were the most frequently sighted species, the former in waters >50 m, frequently from purse seiners and trawlers, and the latter particularly inside the south Galician rías and close to vessels operating further offshore in Portuguese waters. Harbour porpoises were seen over the whole continental shelf, often next to beach seines, while long‐finned pilot whales and striped dolphins were mostly seen from vessels fishing offshore.

Results suggest that cetacean occurrence is linked to prey distribution and that interactions with fisheries are most likely for common dolphins (with coastal purse seines and offshore trawls), bottlenose dolphins and harbour porpoises (coastal nets). The different data sources were complementary and provided results broadly consistent with previous studies on cetacean occurrence in the same area, although sightings frequency for some cetacean species was biased by survey method. Opportunistic sampling has certain restrictions concerning reliability, but can cover a wide area at comparatively low cost and make use of local ecological knowledge to yield information required for cetacean conservation.

Copyright © 2014 John Wiley & Sons, Ltd.
Decadal trends of global precipitation in the recent 30 years
Authors: Li Xiaofan , Zhai Guoqing , Gao Shouting , Shen Xinyong
Published: June 2014

Decadal trends of global precipitation are examined using the Climate Prediction Center (CPC) Merged Analysis of Precipitation (CMAP), Global Precipitation Climatology Project (GPCP), and National Centers for Environmental Prediction (NCEP)/National Center for Atmospheric Research (NCAR) reanalysis data. The decadal trends of global precipitation average diverge a decreasing trend for the CMAP data, a flat trend for the GPCP data, and an increasing trend for the reanalysis data. The decreasing trend for the CMAP data is associated with the reduction in high precipitation. The flat trend for the GPCP data is related to the offset between the increase in high precipitation and the decrease in low precipitation. The increasing trend for the reanalysis data corresponds to the increase in high precipitation.
Randomized clinical trial of isolated Roux-en-Y versus conventional reconstruction after pancreaticoduodenectomy
Authors: Tani M , Kawai M , Hirono S , Okada K-I , Miyazawa M , Shimizu A , Kitahata Y , Yamaue H
Published: June 2014

Background

Pancreaticoduodenectomy (PD) is associated with a high incidence of postoperative complications including pancreatic fistula. This randomized clinical trial compared the incidence of pancreatic fistula between the isolated Roux-en-Y (IsoRY) and conventional reconstruction (CR) methods.

Methods

Patients admitted for PD between June 2009 and September 2012 in a single centre were assigned randomly to CR or IsoRY. The primary endpoint was the incidence of pancreatic fistula (grade A–C) defined according to the International Study Group on Pancreatic Fistula. Secondary endpoints were complication rates, mortality and hospital stay. Multiple logistic regression analysis was performed to identify factors associated with pancreatic fistula.

Results

Some 153 patients were randomized, 76 to CR and 77 to IsoRY; two patients from the IsoRY group were excluded after randomization. Pancreatic fistula occurred in 26 patients (34 per cent) in the CR group and 25 (33 per cent) in the IsoRY group (P = 0·909). The number of patients with a clinically relevant pancreatic fistula (grade B or C) was similar in the two groups (10 and 11 patients respectively; P = 0·789), as were complication rates (42 versus 40 per cent; P = 0·793) and mortality (none in either group; P = 0·999). Soft pancreas was the only independent risk factor for pancreatic fistula (odds ratio 4·42, 95 per cent confidence interval 1·85 to 10·53; P <0·001).

Conclusion

This study showed that IsoRY reconstruction does not reduce the incidence of pancreatic fistula compared with CR. Registration number: NCT00915863 (http://www.clinicaltrials.gov/) and UMIN000001967 (http://www.umin.ac.jp/).
Withholding and canceling a response in ADHD adolescents
Authors: Bhaijiwala Mehereen , Chevrier Andre , Schachar Russell
Published: June 2014

Background

Deficient response inhibition in situations involving a trade‐off between response execution and response stopping is a hallmark of attention deficit hyperactive disorder (ADHD). There are two key components of response inhibition; reactive inhibition where one attempts to cancel an ongoing response and prospective inhibition is when one withholds a response pending a signal to stop. Prospective inhibition comes into play prior to the presentation of the stop signal and reactive inhibition follows the presentation of a signal to stop a particular action. The aim of this study is to investigate the neural activity evoked by prospective and reactive inhibition in adolescents with and without ADHD.

Methods

Twelve adolescents with ADHD and 12 age‐matched healthy controls (age range 9–18) were imaged while performing the stop signal task (SST).

Results

Reactive inhibition activated right inferior frontal gyrus (IFG) in both groups. ADHD subjects activated IFG bilaterally. In controls, prospective inhibition invoked preactivation of the same part of right IFG that activated during reactive inhibition. In ADHD subjects, prospective inhibition was associated with deactivation in this region. Controls also deactivated the medial prefrontal cortex (MPFC) during prospective inhibition, whereas ADHD subjects activated the same area.

Discussion

This pattern of activity changes in the same structures, but in opposite directions, was also evident across all phases of the task in various task‐specific areas like the superior and middle temporal gyrus and other frontal areas.

Conclusion

Differences between ADHD and control participants in task‐specific and default mode structures (IFG and MPFC) were evident during prospective, but not during reactive inhibition.
Iron(II)‐Derived Lewis Acid/Surfactant Combined Catalysis for the Enantioselective Mukaiyama Aldol Reaction in Pure Water
Authors: Lafantaisie Mathieu , Mirabaud Anaïs , Plancq Baptiste , Ollevier Thierry
Published: June 2014

The catalytic asymmetric Mukaiyama aldol reaction in pure water was performed by using a combination of iron(II) dodecyl sulfate, a chiral bipyridine ligand, and benzoic acid. By using the obtained iron(II)‐derived Lewis acid/surfactant combined catalyst, the desired products were afforded in good yields with high diastereo‐ and enantioselectivities.
Super‐Efficient Platinum Catalyst Derived from a Semiconducting, DMF Solvate: Structural, Spectroscopic, Electrochemical, and Catalytic Characterization
Authors: Lu Jinzhen , Abrahams Brendan F. , Winther‐Jensen Bjorn , Martin Lisandra L. , Bond Alan M.
Published: June 2014

The reaction of [(NH3)4Pt](NO3)2with LiTCNQF4(TCNQF4=2,3,5,6‐tetrafluoro‐7,7,8,8‐tetracyanoquinodimethane) in dimethylformamide gives the product [(NH3)4Pt](TCNQF4)2⋅(DMF)4(1). Subtle changes in the solvent conditions, however, result in a different product, [(NH3)4Pt](TCNQF4)2⋅Et2O⋅(CH3OH)4/3(2). Both1and2have been characterized by X‐ray crystallography, vibrational (FTIR, Raman) and UV/vis spectroscopy, thermogravimetric analysis and electrochemistry. Single crystals of1indicate the presence of 3 D networks supported by hydrogen bonding, whereas the structural analysis of2indicates a 2 D layered network, which consists of alternating TCNQF4−and [(NH3)4Pt]2+layers. The conductivity of a single crystal of1at room temperature lies in the semiconducting range (≈2.5×10−6 S cm−1). Unexpectedly,1was found to exhibit an exceptionally high catalytic activity for the electron transfer reaction between ferricyanide and thiosulfate ions in aqueous media. Our analysis indicates that the DMF solvates were removed prior to the catalytic reaction, but no other changes that occur in the chemical composition were found. Thus, the active catalyst is [(NH3)4Pt](TCNQF4)2(3) rather than the starting material1.
Mechanistic Study of CO Titration on CuxO/Cu(1 1 1) (x≤2) Surfaces
Authors: An Wei , Baber Ashleigh E. , Xu Fang , Soldemo Markus , Weissenrieder Jonas , Stacchiola Dario , Liu Ping
Published: June 2014

The reducibility of metal oxides is of great importance to their catalytic behavior. Herein, we combined ambient‐pressure scanning tunneling microscopy (AP–STM), X‐ray photoemission spectroscopy (AP–XPS), and DFT calculations to study the CO titration of CuxO thin films supported on Cu(1 1 1) (CuxO/Cu(1 1 1)) aiming to gain a better understanding of the roles that the Cu(1 1 1) support and surface defects play in tuning catalytic performances. Different conformations have been observed during the reduction, namely, the 44 structure and a recently identified (5–7–7–5) Stone–Wales defects (5–7 structure). The DFT calculations revealed that the Cu(1 1 1) support is important to the reducibility of supported CuxO thin films. Compared with the case for the Cu2O(1 1 1) bulk surface, at the initial stage CO titration is less favorable on both the 44 and 5–7 structures. The strong CuxO↔Cu interaction accompanied with the charge transfer from Cu to CuxO is able to stabilize the oxide film and hinder the removal of O. However, with the formation of more oxygen vacancies, the binding between CuxO and Cu(1 1 1) is weakened and the oxide film is destabilized, and Cu2O(1 1 1) is likely to become the most stable system under the reaction conditions. In addition, the surface defects also play an essential role. With the proceeding of the CO titration reaction, the 5–7 structure displays the highest activity among all three systems. Stone–Wales defects on the surface of the 5–7 structure exhibit a large difference from the 44 structure and Cu2O(1 1 1) in CO binding energy, stability of lattice oxygen, and, therefore, the reduction activity. The DFT results agree well with the experimental measurements, demonstrating that by adopting the unique conformation, the 5–7 structure is the active phase of CuxO, which is able to facilitate the redox reaction and the Cu2O/Cu(1 1 1)↔Cu transition.
Direct Reductive Amination of Ketones: Structure and Activity of S‐Selective Imine Reductases from Streptomyces
Authors: Huber Tobias , Schneider Lisa , Präg Andreas , Gerhardt Stefan , Einsle Oliver , Müller Michael
Published: June 2014

The importance and structural diversity of chiral amines is well‐demonstrated by the myriad nonenzymatic methods for their chemical production. In nature, the production of amines is performed by transamination rather than by reduction of an imine precursor derived from the corresponding ketone. Imine reductases, however, show great potential in the reduction of cyclic imines that are stable towards hydrolysis in aqueous reaction media. Here, we report the catalytic activity of two S‐selective imine reductases towards 3,4‐dihydroisoquinolines and 3,4‐dihydro‐β‐carbolines and their activity in the direct reductive amination of ketone substrates. The crystal structures of the enzyme from Streptomyces sp. GF3546 in complex with the cofactor NADPH and from Streptomyces aurantiacus in native form have been solved and refined to a resolution of 1.9 Å.
A Soluble Ladder‐Conjugated Star‐Shaped Oligomer Composed of Four Perylene Diimide Branches and a Fluorene Core: Synthesis and Properties
Authors: Zhang Youdi , Chen Lingcheng , Zhang Kaichen , Wang Helin , Xiao Yi
Published: June 2014

A new ladder‐conjugated star‐shaped oligomer electron‐transporting material TetraPDI‐PF, with four perylene diimide (PDI) branches and a fluorene core, was efficiently synthesized. The oligomer is highly soluble in dichlorobenzene with a solubility of 155 mg mL−1, which is higher than those of PDI (35 mg mL−1) and PDI‐Phen (70 mg mL−1). Demonstrated by thermogravimetric analysis (TGA), the oligomer exhibits excellent thermal stability with the decomposition temperature (Td) of 291.2 °C, which is 65 °C higher than that of PDI. Cyclic voltammetry (CV) and differential pulse voltammetry (DPV) were employed to investigate the electrochemical properties. Although the CV curves of TetraPDI‐PF are successively scanned for 15 cycles, they still remain invariable reduction potentials. The oligomer also shows outstanding photostability, even better than PDI, which maintains 99 % fluorescence intensity after irradiation for 10 min using maximum laser intensity. In the steady‐state space‐charge‐limited current (SCLC) devices, TetraPDI‐PF exhibits higher intrinsic electron mobility of 2.22×10−5 cm2 V−1 s−1, three orders of magnitude over that of PDI (3.52×10−8 cm2 V−1 s−1). The bulk heterojunction (BHJ) organic solar cells (OSCs) using TetraPDI‐PF as non‐fullerene acceptors and P3HT as donors give optimum power conversion efficiency (PCE) of 0.64 %, which is 64 times that of the PDI:P3HT BHJ cells.
A Valence Bond Model for Electron‐Rich Hypervalent Species: Application to SFn (n=1, 2, 4), PF5, and ClF3
Authors: Braida Benoit , Ribeyre Tristan , Hiberty Philippe C.
Published: June 2014

Some typical hypervalent molecules, SF4, PF5, and ClF3, as well as precursors SF (4Σ− state) and SF2 (3B1 state), are studied by means of the breathing‐orbital valence bond (BOVB) method, chosen for its capability of combining compactness with accuracy of energetics. A unique feature of this study is that for the first time, the method used to gain insight into the bonding modes is the same as that used to calculate the bonding energies, so as to guarantee that the qualitative picture obtained captures the essential physics of the bonding system. The 4Σ− state of SF is shown to be bonded by a three‐electron σ bond assisted by strong π back‐donation of dynamic nature. The linear 3B1 state of SF2, as well as the ground states of SF4, PF5 and ClF3, are described in terms of four VB structures that all have significant weights in the range 0.17–0.31, with exceptionally large resonance energies arising from their mixing. It is concluded that the bonding mode of these hypervalent species and isoelectronic ones complies with Coulson’s version of the Rundle–Pimentel model, but assisted by charge‐shift bonding. The conditions for hypervalence to occur are stated.
Probing the Rotational Dynamics of meso‐(2‐Substituted)aryl Substituents in A2B‐Type Subporphyrins
Authors: Yoshida Kota , Copley Graeme , Mori Hirotaka , Osuka Atsuhiro
Published: June 2014

A2B‐type B‐methoxy subporphyrins 3 a–g and B‐phenyl subporphyrins 7 a–c,e,g bearing meso‐(2‐substituted)aryl substituents are synthesized, and their rotational dynamics are examined through variable‐temperature (VT) 1H NMR spectroscopy. In these subporphyrins, the rotation of meso‐aryl substituents is hindered by a rationally installed 2‐substituent. The rotational barriers determined are considerably smaller than those reported previously for porphyrins. Comparison of the rotation activation parameters reveals a variable contribution of ΔH≠ and ΔS≠ in ΔG≠. 2‐Methyl and 2‐ethyl groups of the meso‐aryl substituents in subporphyrins 3 e, 3 f, and 7 e induce larger rotational barriers than 2‐alkoxyl substituents. The rotational barriers of 3 g and 7 g are reduced by the presence of the 4‐dibenzylamino group owing to its ability to stabilize the coplanar rotation transition state electronically. The smaller rotational barriers found for B‐phenyl subporphyrins than for B‐methoxy subporphyrins indicate a negligible contribution of SN1‐type heterolysis in the rotation of meso‐aryl substituents.
2‐Chloro‐Azaborolyl Anion: A Source of 1,2‐Azaborole Isosteric to Cyclopentadienylidene
Authors: Xie Liang , Zhang Jianying , Cui Chunming
Published: June 2014

Azaborolyl anions, the five‐membered BN heterocycles, have attracted a considerable attention due to their aromaticity and isoelectronic relationship with ubiquitous cyclopentadienyl ligands. Besides their syntheses and applications in the preparation of metal complexes, the other aspects of their chemistry have been virtually unexplored. Reduction of the azabutadienyl chelate boron dichloride [ArNC(R)CHC(R)]BCl2 (2, Ar=2,6‐Me2C6H3, R=tBu) with two equivalents of potassium yielded the novel 2‐chloro‐azaborolyl anion [ArNC(R)CHC(R)BCl]K(thf) (3) as a stable product in good yield. Reaction of 3 with 1,3,4,5‐tetramethylimidazol‐2‐ylidene (NHC) yielded the first NHC–azaborole adduct with the elimination of KCl. The salt elimination reaction was also observed in the reactions with H2O and the organic azide ArN3, leading to the formation of an oxo‐bridged 3H‐1,2‐diazaborole and an intramolecular donor‐stabilized iminoborane, demonstrating that 3 is a source of the unexplored 1,2‐azaborole isosteric to cyclopentadienylidene.
Large Spin‐Relaxation Barriers for the Low‐Symmetry Organolanthanide Complexes [Cp*2Ln(BPh4)] (Cp*=pentamethylcyclopentadienyl; Ln=Tb, Dy)
Authors: Demir Selvan , Zadrozny Joseph M. , Long Jeffrey R.
Published: June 2014

Single‐molecule magnets comprising one spin center represent a fundamental size limit for spin‐based information storage. Such an application hinges upon the realization of molecules possessing substantial barriers to spin inversion. Axially symmetric complexes of lanthanides hold the most promise for this due to their inherently high magnetic anisotropies and low tunneling probabilities. Herein, we demonstrate that strikingly large spin reversal barriers of 216 and 331 cm−1 can also be realized in low‐symmetry lanthanide tetraphenylborate complexes of the type [Cp*2Ln(BPh4)] (Cp*=pentamethylcyclopentadienyl; Ln=Tb (1) and Dy (2)). The dysprosium congener showed hysteretic magnetization data up to 5.3 K. Further studies of the magnetic relaxation processes of 1 and 2 under applied dc fields and upon dilution within a matrix of [Cp*2Y(BPh4)] revealed considerable suppression of the tunneling pathway, emphasizing the strong influence of dipolar interactions on the low‐temperature magnetization dynamics in these systems.
Lung parenchymal signal intensity in MRI: A technical review with educational aspirations regarding reversible versus irreversible transverse relaxation effects in common pulse sequences
Authors: Mulkern Robert , Haker Steven , Mamata Hatsuho , Lee Edward , Mitsouras Dimitrios , Oshio Koichi , Balasubramanian Mukund , Hatabu Hiroto
Published: June 2014

Lung parenchyma is challenging to image with proton MRI. The large air space results in ∼1/5th as many signal‐generating protons compared to other organs. Air/tissue magnetic susceptibility differences lead to strong magnetic field gradients throughout the lungs and to broad frequency distributions, much broader than within other organs. Such distributions have been the subject of experimental and theoretical analyses which may reveal aspects of lung microarchitecture useful for diagnosis. Their most immediate relevance to current imaging practice is to cause rapid signal decays, commonly discussed in terms of short T2* values of 1 ms or lower at typical imaging field strengths. Herein we provide a brief review of previous studies describing and interpreting proton lung spectra. We then link these broad frequency distributions to rapid signal decays, though not necessarily the exponential decays generally used to define T2* values. We examine how these decays influence observed signal intensities and spatial mapping features associated with the most prominent torso imaging sequences, including spoiled gradient and spin echo sequences. Effects of imperfect refocusing pulses on the multiple echo signal decays in single shot fast spin echo (SSFSE) sequences and effects of broad frequency distributions on balanced steady state free precession (bSSFP) sequence signal intensities are also provided. The theoretical analyses are based on the concept of explicitly separating the effects of reversible and irreversible transverse relaxation processes, thus providing a somewhat novel and more general framework from which to estimate lung signal intensity behavior in modern imaging practice. © 2014 Wiley Periodicals, Inc. Concepts Magn Reson Part A 43A: 29–53, 2014.
A chaotic map‐based anonymous multi‐server authenticated key agreement protocol using smart card
Authors: Tsai Jia‐Lun , Lo Nai‐Wei
Published: June 2014

Authenticated key agreement protocols play an important role for network‐connected servers to authenticate remote users in Internet environment. In recent years, several authenticated key agreement protocols for single‐server environment have been developed based on chaotic maps. In modern societies, people usually have to access multiple websites or enterprise servers to accomplish their daily personal matters or duties on work; therefore, how to increase user's convenience by offering multi‐server authentication protocol becomes a practical research topic. In this study, a novel chaotic map‐based anonymous multi‐server authenticated key agreement protocol using smart card is proposed. In this protocol, a legal user can access multiple servers using only a single secret key obtained from a trusted third party, known as the registration center. Security analysis shows this protocol is secure against well‐known attacks. In addition, protocol efficiency analysis is conducted by comparing the proposed protocol with two recently proposed schemes in terms of computational cost during one authentication session. We have shown that the proposed protocol is twice faster than the one proposed by Khan and He while preserving the same security properties as their protocol has. Copyright © 2014 John Wiley & Sons, Ltd.
Does imprint cytology improve the accuracy of transrectal prostate needle biopsy?
Authors: Sayar Hamide , Bulut Burak Besir , Bahar Abdulkadir Yasir , Bahar Mustafa Remzi , Seringec Nurten , Resim Sefa , Çıralık Harun
Published: June 2014

Objective

To evaluate the accuracy of imprint cytology of core needle biopsy specimens in the diagnosis of prostate cancer.

Methods

Between December 24, 2011 and May 9, 2013, patients with an abnormal DRE and/or serum PSA level of >2.5 ng/mL underwent transrectal prostate needle biopsy. Samples with positive imprint cytology but negative initial histologic exam underwent repeat sectioning and histological examination.

Results

1,262 transrectal prostate needle biopsy specimens were evaluated from 100 patients. Malignant imprint cytology was found in 236 specimens (18.7%), 197 (15.6%) of which were confirmed by histologic examination, giving an initial 3.1% (n = 39) rate of discrepant results by imprint cytology. Upon repeat sectioning and histologic examination of these 39 biopsy samples, 14 (1.1% of the original specimens) were then diagnosed as malignant, 3 (0.2%) as atypical small acinar proliferation (ASAP), and 5 (0.4%) as high‐grade prostatic intraepithelial neoplasia (HGPIN). Overall, 964 (76.4%) specimens were negative for malignancy by imprint cytology. Seven (0.6%) specimens were benign by cytology but malignant cells were found on histological evaluation. On imprint cytology examination, nonmalignant but abnormal findings were seen in 62 specimens (4.9%). These were all due to benign processes. After reexamination, the accuracy, sensitivity, specificity, positive predictive value, negative predictive value, false‐positive rate, false‐negative rate of imprint preparations were 98.1, 96.9, 98.4, 92.8, 99.3, 1.6, 3.1%, respectively.

Conclusion

Imprint cytology is valuable tool for evaluating TRUS‐guided core needle biopsy specimens from the prostate. Use of imprint cytology in combination with histopathology increases diagnostic accuracy when compared with histopathologic assessment alone. Diagn. Cytopathol. 2015;43:91–97. © 2014 Wiley Periodicals, Inc.
The immediate protective response to microbial challenge
Authors: González‐Navajas José M. , Corr Mary P. , Raz Eyal
Published: June 2014

The innate immune system detects infection and tissue injury through different families of pattern‐recognition receptors (PRRs), such as Toll‐like receptors. Most PRR‐mediated responses initiate elaborate processes of signaling, transcription, translation, and secretion of effector mediators, which together require time to achieve. Therefore, PRR‐mediated processes are not active in the early phases of infection. These considerations raise the question of how the host limits microbial replication and invasion during this critical period. Here, we examine the crucial defense mechanisms, such as antimicrobial peptides or extracellular traps, typically activated within minutes of the initial infection phase, which we term the “immediate protective response”. Deficiencies in different components of the immediate protective response are often associated with severe and recurrent infectious diseases in humans, highlighting their physiologic importance.
Cognate interactions: Extrafollicular IL‐4 drives germinal‐center reactions, a new role for an old cytokine
Authors: Toellner Kai‐Michael
Published: June 2014

Over the past 25 years it has become clear that B and T lymphocytes go through a range of interactions and migratory events when B cells differentiate to become high‐affinity, antibody‐secreting cells. This B‐cell differentiation is associated with multiple sequential cognate interactions. In this issue of the European Journal of Immunology, Turqueti‐Neves et al. [Eur. J. Immunol. 2014. 44: 2130–2138] show that IL‐4, a cytokine well known as a regulator of Ig class switch recombination, has another as‐yet‐unappreciated role. The authors show that IL‐4 produced by T‐helper cells outside germinal centers has a major effect on the early stages of germinal‐center B‐cell differentiation. This Commentary will summarize their findings and relate them to what we know on the sequence of cognate interactions and migratory events B cells undergo during T‐dependent immune responses.
Origins of the Ideas in Evaluating with Validity
Authors: House Ernest R.
Published: June 2014

The book Evaluating with Validity (House, ) broadened the evaluation field's conception of validity by contending that evaluations should be true, coherent, and just. Untrue, incoherent, and unjust evaluations are invalid. The working ideas were argument, coherence, and politics. Truth is the attainment of arguments soundly made, beauty is the attainment of coherence well wrought, and justice is the attainment of politics fairly done. For the truth criterion, it wasn't designs or correlations that determined validity, but rather the validity of the arguments that supported the use of the designs and correlations. The broader conception of validity grew from addressing problems encountered in conducting evaluations. This chapter traces the origins of the ideas and the social context from which they emerged. It contends that these criteria still apply, though the contents of the criteria have changed somewhat and the context has changed substantially.
Credible Judgment: Combining Truth, Beauty, and Justice
Authors: Hurteau Marthe , Williams David D.
Published: June 2014

The research summarized in this chapter provides descriptive evidence to support House's vision of validity by expanding connections with his theory to a wide variety of professions, in addition to professional evaluators. Perhaps these results and discussion of them and the emerging model will invite professionals to reflect upon ways to improve their own evaluative judgments. Case study interviews were conducted in Canada and the United States with 27 professionals from many helping professions, including law and law enforcement, social work, medicine, education, business, sports, and chaplaincy. Participants were asked to discuss examples of successful and less successful evaluative judgments they had made in their professional work. Citing patterns discovered through analysis of these contrasting examples, we linked their experiences to House's framework regarding truth, beauty, and justice as foundations for validity. This research thus generated a descriptive model of a process to produce credible evaluation judgments with six interacting elements: (1) credible judgments evolve through an iterative process; (2) frameworks, protocols, and methods may help professionals generate valid evidence, but they are often not sufficient; (3) stakeholders’ involvement is essential, and how they participate varies depending on the circumstances; (4) the path required to generate a credible judgment is rarely linear; (5) credible judgment is based on strong argumentation that is properly developed and aesthetically presented; (6) the production of credible judgments depends on special dispositions, orientations, or qualities of the professionals.
Negotiating Truth, Beauty, and Justice: A Politically Responsive Approach
Authors: Azzam Tarek , Levine Bret
Published: June 2014

Evaluation design and implementation are not technocratic exercises, but are processes that require negotiations with stakeholders and careful design. This chapter focuses on the nontechnical factors that affect these processes and discusses cases and studies to illustrate their influence. The chapter concludes by introducing the concept of politically responsive evaluation as an organizing frame to help evaluators consider some of the nontechnical issues that influence evaluations.
Justice Signposts in Evaluation Theory, Practice, and Policy
Authors: Hopson Rodney K.
Published: June 2014

This chapter, influenced by Ernest House's conceptions of justice from his Evaluating with Validity seminal book, offers two justice signposts in contemporary evaluation theory, practice, and policy. The justice turn in evaluation privileges issues of power, fairness, justice, and rights beyond practical and technical considerations. Cases and examples draw upon Housian notions of justice in advancing and making obvious how evaluation may contribute to more just practices, systems, and structures in our larger society.
Selective Synthesis of Quinolines and Indoles: Sulfur‐Assisted or Selenium‐Catalyzed Reaction of β‐(2‐Nitrophenyl)‐α,β‐unsaturated Ketones with Carbon Monoxide
Authors: Umeda Rui , Kouno Hiroshi , Kitagawa Takayuki , Okamoto Tomohiro , Kawashima Keisuke , Mashino Tsukasa , Nishiyama Yutaka
Published: June 2014

A simple and selective synthetic method of quinolines and indoles by the reaction of β‐(2‐nitrophenyl)‐α,β‐unsaturated ketones with carbon monoxide was developed. When β‐(2‐nitrophenyl)‐α,β‐unsaturated ketones were allowed to react with carbon monoxide and water in the presence of a stoichiometric amount of sulfur or a catalytic amount of selenium, the corresponding quinolines were produced in moderate‐to‐good yields. On the other hand, in the absence of water, the indoles were produced by the selenium‐catalyzed reaction of the β‐(2‐nitrophenyl)‐α,β‐unsaturated ketones with carbon monoxide.
Synthesis of the Mixed Alkyl Esters of Phenylphosphonic Acid by Two Variations of the Atherton–Todd Protocol
Authors: Ilia Gheorghe , Petric Mihaela , Bálint Erika , Keglevich György
Published: June 2014

Phenylphosphonates with mixed alkyl groups were synthesized from ethyl phenyl‐H‐phosphinate by two modified Atherton–Todd methods. Using aqueous sodium hydroxide under phase transfer catalytic conditions, the alkyl ethyl phosphonates were obtained in only moderate yields. However, applying 1‐methylimidazole as the base, the diesters could be prepared in yields of 76–85%. The imidazole hydrochloride formed as a by‐product acts as an ionic liquid phase in the reaction, from which the base can be regenerated.
Flood frequency under the influence of trends in the Pearl River basin, China: changing patterns, causes and implications
Authors: Zhang Qiang , Gu Xihui , Singh Vijay P. , Xiao Mingzhong , Xu Chong‐Yu
Published: June 2014

Using a nonstationary flood frequency model, this study investigates the impact of trends on the estimation of flood frequencies and flood magnification factors. Analysis of annual peak streamflow data from 28 hydrological stations across the Pearl River basin, China, shows that: (1) northeast parts of the West and the North River basins are dominated by increasing annual peak streamflow, whereas decreasing trends of annual peak streamflow are prevailing in other regions of the Pearl River basin; (2) trends significantly impact the estimation of flood frequencies. The changing frequency of the same flood magnitude is related to the changing magnitude or significance/insignificance of trends, larger increasing frequency can be detected for stations with significant increasing trends of annual peak streamflow and vice versa, and smaller increasing magnitude for stations with not significant increasing annual peak streamflow, pointing to the critical impact of trends on estimation of flood frequencies; (3) larger‐than‐1 flood magnification factors are observed mainly in the northeast parts of the West River basin and in the North River basin, implying magnifying flood processes in these regions and a higher flood risk in comparison with design flood‐control standards; and (4) changes in hydrological extremes result from the integrated influence of human activities and climate change. Generally, magnifying flood regimes in the northeast Pearl River basin and in the North River basin are mainly the result of intensifying precipitation regime; smaller‐than‐1 flood magnification factors along the mainstream of the West River basin and also in the East River basin are the result of hydrological regulations of water reservoirs. Copyright © 2014 John Wiley & Sons, Ltd.
Simulating Biomolecular Folding and Function by Native‐Structure‐Based/Go‐Type Models
Authors: Sinner Claude , Lutz Benjamin , John Shalini , Reinartz Ines , Verma Abhinav , Schug Alexander
Published: June 2014

The 2013 Nobel Prize in Chemistry highlights how crucial computer simulations have become for many scientific and engineering fields. Nowadays, scientific progress is not only driven by the interplay of new experimental measurements and increasingly sophisticated theoretical frameworks, but also by an incredible toolbox of complex computational models meeting ubiquitously available computing power and data storage facilities. Quantum mechanical (QM) calculations can be condensed into molecular mechanics (MM) force fields and coupled QM/MM calculations can derive atomic and molecular properties of biomolecular or materials science systems with high accuracy. Pure MM simulations driven by Monte Carlo or molecular dynamics algorithms are widely applied in biological chemistry/physics and can investigate large biomolecular systems, such as proteins, DNA, or RNA. One coarse‐grained class of these models, native‐structure‐based or Go models, are based on energy landscape theory and the principle of minimal frustration. Herein, an ensemble of converging pathways guide protein folding on a funnel‐like shape of the entire energy landscape towards the native state. Simulations based on these ideas have been tremendously successful in explaining protein folding and function. Their history and recent application highlights are reviewed.
An innovative three‐dimensional gelatin foam culture system for improved study of glioblastoma stem cell behavior
Authors: Yang Meng‐Yin , Chiao Ming‐Tsang , Lee Hsu‐Tung , Chen Chien‐Min , Yang Yi‐Chin , Shen Chiung‐Chyi , Ma Hsin‐I.
Published: June 2014

Three‐dimensional (3‐D) tissue engineered constructs provide a platform for examining how the local extracellular matrix contributes to the malignancy of various cancers, including human glioblastoma multiforme. Here, we describe a simple and innovative 3‐D culture environment and assess its potential for use with glioblastoma stem cells (GSCs) to examine the diversification inside the cell mass in the 3‐D culture system. The dissociated human GSCs were cultured using gelatin foam. These cells were subsequently identified by immunohistochemical staining, reverse transcriptase‐polymerase chain reaction, and Western blot assay. We demonstrate that the gelatin foam provides a suitable microenvironment, as a 3‐D culture system, for GSCs to maintain their stemness. The gelatin foam culture system contributes a simplified assessment of cell blocks for immunohistochemistry assay. We show that the significant transcription activity of hypoxia and the protein expression of inflammatory responses are detected at the inside of the cell mass in vitro, while robust expression of PROM1/CD133 and hypoxia‐induced factor‐1 alpha are detected at the xenografted tumor in vivo. We also examine the common clinical trials under this culture platform and characterized a significant difference of drug resistance. The 3‐D gelatin foam culture system can provide a more realistic microenvironment through which to study the in vivo behavior of GSCs to evaluate the role that biophysical factors play in the hypoxia, inflammatory responses and subsequent drug resistance. © 2014 Wiley Periodicals, Inc. J Biomed Mater Res Part B: Appl Biomater, 103B: 618–628, 2015.
Effect of oxide layer modification of CoCr stent alloys on blood activation and endothelial behavior
Authors: Milleret Vincent , Ziogas Algirdas , Buzzi Stefano , Heuberger Roman , Zucker Arik , Ehrbar Martin
Published: June 2014

CoCr alloys, in particular MP35N and L605, are extensively used in biomedical implants, for example for coronary stents. In practice, these alloys present a moderately hydrophobic surface which leads to significant platelet adhesion and consequently to risk of early thrombosis or in‐stent restenosis. Surface modification of biomedical implants is known to alter their biological performances. In this study we focused on the alteration of in vitro biological responses of human cells contacting CoCr surfaces with engineered oxide layers. XPS analysis was performed to determine the composition of the oxide layer of differently treated CoCr while the bulk properties were not modified. An extensive characterization of the surfaces was performed looking at surface roughness, wettability and charge. After static exposure to blood, strongly reduced platelet and increased polymorphonuclear neutrophil adhesion were observed on treated versus untreated surfaces. Comparisons of treated and untreated samples provide evidence for wettability being an important player for platelet adhesion, although multiple factors including surface oxide chemistry and charge might control polymorphonuclear neutrophil adhesion. The differently treated surfaces were shown to be equally suitable for endothelial cell proliferation. We herein present a novel approach to steer biological properties of CoCr alloys. By adjusting their oxide layer composition, substrates were generated which are suitable for endothelial cell growth and at the same time show an altered (reduced) blood contact activation. Such treatments are expected to lead to stents of highly reproducible quality with minimal thrombogenicity and in‐stent restenosis, while maintaining rapid re‐endothelialization after coronary angioplasty. © 2014 Wiley Periodicals, Inc. J Biomed Mater Res Part B: Appl Biomater, 103B: 629–640, 2015.
Biosimilar monoclonal antibodies: A Canadian regulatory perspective on the assessment of clinically relevant differences and indication extrapolation
Authors: Scott Bradley J. , Klein Agnes V. , Wang Jian
Published: June 2014

Monoclonal antibodies have become mainstays of treatment for many diseases. After more than a decade on the Canadian market, a number of authorized monoclonal antibody products are facing patent expiry. Given their success, most notably in the areas of oncology and autoimmune disease, pharmaceutical and biotechnology companies are eager to produce their own biosimilar versions and have begun manufacturing and testing for a variety of monoclonal antibody products. In October of 2013, the first biosimilar monoclonal antibody products were approved by the European Medicines Agency (Remsima™ and Inflectra™). These products were authorized by Health Canada shortly after; however, while the EMA allowed for extrapolation to all of the indications held by the reference product, Health Canada limited extrapolation to a subset of the indications held by the reference product, Remicade®. The purpose of this review is to discuss the Canadian regulatory framework for the authorization of biosimilar mAbs with specific discussion around the clinical requirements for establishing (bio)‐similarity and to present the principles that are used in the clinical assessment of New Drug Submissions for intended biosimilar monoclonal antibodies. Health Canada's current views regarding indication extrapolation, product interchangeability, and post‐market surveillance are discussed as well.