bluuebunny/crossref_metadata_2025 huggingface dataset:
Reliable Exclusion of Acute Coronary Syndrome Among Hospitalized Patients With Elevated Troponin
Authors: Davis Melinda B. , Shafton Asher , Desai Aken , Childers David , Bach David S.
Published: February 2014

Background

Elevated cardiac troponin I (cTnI) occurs in acute coronary syndrome (ACS) as well as various scenarios not associated with ACS.

Hypothesis

Simple clinical criteria can reliably exclude ACS among hospitalized patients with elevated cTnI.

Methods

Records for patients hospitalized from January to April 2011 with elevated cTnI (>0.29 ng/dL) and an available echocardiogram were retrospectively reviewed. Patients with ST‐segment elevation myocardial infarction were excluded. Based on available clinical data, patients were classified as having ACS or elevation of cTnI unrelated to ACS (non‐ACS). Median follow‐up was 365 days.

Results

Of 265 records meeting inclusion criteria, 82 (31%) had ACS and 183 (69%) had non‐ACS. In multivariable analysis, odds ratios for non‐ACS were 7.6 (95% confidence interval [CI]: 3.8‐15.3) for peak cTnI <2 ng/dL, 6.3 (95% CI: 3.1‐13.0) for absent wall‐motion abnormality, and 4.4 (95% CI: 2.2‐8.6) for no prior coronary artery disease history. The area under the receiver operating curve for a model using these 3 variables was 0.86, with a 98% negative predictive value for excluding ACS. Patients who met these 3 criteria had no ACS‐related deaths over 1‐year follow‐up.

Conclusions

Hospitalized patients with peak Tn level <2 ng/dL, no prior history of coronary artery disease, and no new echocardiographic wall‐motion abnormality appear to have a very low likelihood of ACS. Prospective validation of these results is needed to determine whether additional diagnostic testing could be safely avoided in hospitalized patients meeting these simple clinical criteria.
Towards Matched Pairs of Porphyrin–ReI/99mTcI Conjugates that Combine Photodynamic Activity with Fluorescence and Radio Imaging
Authors: Gianferrara Teresa , Spagnul Cinzia , Alberto Roger , Gasser Gilles , Ferrari Stefano , Pierroz Vanessa , Bergamo Alberta , Alessio Enzo
Published: February 2014

We recently prepared two novel water soluble porphyrins bearing a single peripheral chelator, either diethylenetriamine (1) or bipyridyl (2), tethered to one meso position. The preparation of their conjugates with a fac‐{99mTc(CO)3}+ fragment and the potential of these resulting conjugates as fluorescence and radio imaging tools were also described. In this work, we focused on the corresponding non‐radioactive analogues that bear the fac‐{Re(CO)3}+ fragment (diethylenetriamine 3 and bipyridyl 4). We report on the uptake, in vitro PDT activity, and cellular localization of ReI conjugates 3 and 4 in comparison to the parent porphyrins 1 and 2. Compounds 1–4 have modest or negligible cytotoxicity in the dark against HeLa human cervical cancer cells but become remarkably cytotoxic after exposure to moderate doses of red visible light (590–700 nm). This phototoxicity was found to be directly proportional to the total light dose. Although the four compounds show distinct uptake patterns, they have comparable PDT activity. Confocal fluorescence measurements showed that porphyrin 1 and its ReI conjugate 3 have different cellular localization patterns in HeLa cells.
Effects of the Tumor‐Vasculature‐Disrupting Agent Verubulin and Two Heteroaryl Analogues on Cancer Cells, Endothelial Cells, and Blood Vessels
Authors: Mahal Katharina , Resch Marcus , Ficner Ralf , Schobert Rainer , Biersack Bernhard , Mueller Thomas
Published: February 2014

Two analogues of the discontinued tumor vascular‐disrupting agent verubulin (Azixa®, MPC‐6827, 1) featuring benzo‐1,4‐dioxan‐6‐yl (compound 5 a) and N‐methylindol‐5‐yl (compound 10) residues instead of the para‐anisyl group on the 4‐(methylamino)‐2‐methylquinazoline pharmacophore, were prepared and found to exceed the antitumor efficacy of the lead compound. They were antiproliferative with single‐digit nanomolar IC50 values against a panel of nine tumor cell lines, while not affecting nonmalignant fibroblasts. Indole 10 surpassed verubulin in seven tumor cell lines including colon, breast, ovarian, and germ cell cancer cell lines. In line with docking studies indicating that compound 10 may bind the colchicine binding site of tubulin more tightly (Ebind=−9.8 kcal mol−1) than verubulin (Ebind=−8.3 kcal mol−1), 10 suppressed the formation of vessel‐like tubes in endothelial cells and destroyed the blood vessels in the chorioallantoic membrane of fertilized chicken eggs at nanomolar concentrations. When applied to nude mice bearing a highly vascularized 1411HP germ cell xenograft tumor, compound 10 displayed pronounced vascular‐disrupting effects that led to hemorrhages and extensive central necrosis in the tumor.
GluN2B‐Selective N‐Methyl‐d‐aspartate (NMDA) Receptor Antagonists Derived from 3‐Benzazepines: Synthesis and Pharmacological Evaluation of Benzo[7]annulen‐7‐amines
Authors: Benner Andre , Bonifazi Alessandro , Shirataki Chikako , Temme Louisa , Schepmann Dirk , Quaglia Wilma , Shoji Osami , Watanabe Yoshihito , Daniliuc Constantin , Wünsch Bernhard
Published: February 2014

Given their high neuroprotective potential, ligands that block GluN2B‐containing N‐methyl‐D‐aspartate (NMDA) receptors by interacting with the ifenprodil binding site located on the GluN2B subunit are of great interest for the treatment of various neuronal disorders. In this study, a novel class of GluN2B‐selective NMDA receptor antagonists with the benzo[7]annulene scaffold was prepared and pharmacologically evaluated. The key intermediate, N‐(2‐methoxy‐5‐oxo‐6,7,8,9‐tetrahydro‐5H‐benzo[7]annulen‐7‐yl)acetamide (11), was obtained by cyclization of 3‐acetamido‐5‐(3‐methoxyphenyl)pentanoic acid (10 b). The final reaction steps comprise hydrolysis of the amide, reduction of the ketone, and reductive alkylation, leading to cis‐ and trans‐configured 7‐(ω‐phenylalkylamino)benzo[7]annulen‐5‐ols. High GluN2B affinity was observed with cis‐configured γ‐amino alcohols substituted with a 3‐phenylpropyl moiety at the amino group. Removal of the benzylic hydroxy moiety led to the most potent GluN2B antagonists of this series: 2‐methoxy‐N‐(3‐phenylpropyl)‐6,7,8,9‐tetrahydro‐5H‐benzo[7]annulen‐7‐amine (20 a, Ki=10 nM) and 2‐methoxy‐N‐methyl‐N‐(3‐phenylpropyl)‐6,7,8,9‐tetrahydro‐5H‐benzo[7]annulen‐7‐amine (23 a, Ki=7.9 nM). The selectivity over related receptors (phencyclidine binding site of the NMDA receptor, σ1 and σ2 receptors) was recorded. In a functional assay measuring the cytoprotective activity of the benzo[7]annulenamines, all tested compounds showed potent NMDA receptor antagonistic activity. Cytotoxicity induced via GluN2A subunit‐containing NMDA receptors was not inhibited by the new ligands.
CMOS based Q‐switch for low‐power pulsed14N quadruple resonance
Authors: Aissani Sarra , Guendouz Laouès , Canet Daniel
Published: February 2014

In order to reduce the recovery time of the nuclear quadrupole resonance probe (which implies the insertion of a dead time between the end of the pulse and the beginning of signal acquisition), several strategies have been proposed in the case of high‐power radio frequency (rf) pulses. In fact, these strategies rely on a common principle, which is to lower, for an appropriate duration, the probe quality factor immediately after the transmit pulse. The quality factor is then restored for the receive period. In the case of a low‐power rf pulses, we propose a very simple circuit that can alleviate the ringing following the rf pulse just by controlling a rf complementary metal–oxide–semiconductor (CMOS) switch inside the probe circuit. Such a technology features a low insertion loss and a low consumption, the switch being driven by a single‐pin low voltage CMOS or transistor‐transistor logic (TTL) control input. These properties are quite suitable for portable applications. Moreover, we have found that, for simple one‐pulse experiments, this technology provides undistorted 14N quadrupole resonance spectra along with a significant improvement of the signal‐to‐noise ratio in the case of relatively broad lines involving a fine structure. © 2014 Wiley Periodicals, Inc. Concepts Magn Reson Part B (Magn Reson Engineering) 44B: 12–17, 2014
Analytical expressions for magnetic fields and field gradients of current‐carrying triangles
Authors: Forthmann Peter , Amthor Thomas
Published: February 2014

We present an analytical method for calculating magnetic field gradients generated by arbitrary triangulated surfaces. Our work builds upon the results published by Pissanetzky and Xiang, who presented formulas for calculating the magnetic field of current‐carrying faceted surfaces. We show that the analytical gradient expressions can be computed considerably faster than finite field value differences. We also find that the aforementioned published expressions for the magnetic field can be simplified and optimized substantially. Closer inspection of the algorithms, for both field and gradient, reveals a number pathological parameter constellations, which require special treatment. We present a detailed discussion on this. Our results can be directly applied in the optimization of complex magnetic field coils, such as magnetic resonance gradient coils. © 2014 Wiley Periodicals, Inc. Concepts Magn Reson Part B (Magn Reson Engineering) 44B: 18–25, 2014
Prognostic significance of cytoskeleton‐associated membrane protein 4 and its palmitoyl acyltransferase DHHC2 in hepatocellular carcinoma
Authors: Li Shuang‐Xi , Tang Gu‐Sheng , Zhou Dong‐Xun , Pan Yu‐Fei , Tan Ye‐Xiong , Zhang Jian , Zhang Bo , Ding Zhi‐Wen , Liu Li‐Juan , Jiang Tian‐Yi , Hu He‐Ping , Dong Li‐Wei , Wang Hong‐Yang
Published: February 2014

BACKGROUND

The functions of cytoskeleton‐associated membrane protein 4 (CKAP4), one kind of type II transmembrane protein, are associated with the palmitoyl acyltransferase DHHC2. The objective of the current study was to investigate CKAP4/DHHC2 expression and its prognostic significance in patients with hepatocellular carcinoma (HCC).

METHODS

Two independent cohorts of 416 patients with HCC were enrolled. All the patients included had defined clinicopathologic and follow‐up data. Using real‐time polymerase chain reaction and immunohistochemical assay, CKAP4 and DHHC2 expression were evaluated. The association between CKAP4/DHHC2 expression and HCC‐specific disease‐free survival and overall survival was analyzed by Kaplan‐Meier curves, the log‐rank test, and Multivariate Cox regression analyses.

RESULTS

The data documented that CKAP4 expression was much higher in HCC tumor tissues compared with adjacent normal tissues and its expression was significantly correlated with tumor size, intrahepatic metastases, portal venous invasion, and Barcelona Clinic Liver Cancer stage of disease in 2 cohorts of patients. On survival analysis, patients with high CKAP4 expression appeared to have a favorable overall survival and a longer disease‐free survival compared with those with low expression. DHHC2 expression was also examined in tissue microarray analysis by immunohistochemistry and the results demonstrated that 87.6% of the cases had low expression of DHHC2. Kaplan‐Meier analysis indicated that a high level of DHHC2 expression predicted favorable overall survival and disease‐free survival rates in both the training cohort and validation set. Furthermore, the combination of CKAP4 and DHHC2 was found to have a more powerful efficiency in prognosis prediction than either one alone.

CONCLUSIONS

To the best of our knowledge, the current study is the first to demonstrate that the expression of CKAP4 and its palmitoyl acyltransferase DHHC2 correlates with disease progression and metastasis in patients with HCC and may provide prognostic and therapeutic value. Cancer 2014;120:1520–1531. © 2014 American Cancer Society.
Reprocessing unsatisfactory ThinPrep Papanicolaou tests using a modified SurePath preparation technique
Authors: Randolph Melissa L. , Wu Howard H. , Crabtree William N.
Published: February 2014

BACKGROUND

The frequency of unsatisfactory gynecologic specimens has increased in the study laboratory over the last few years due to the advent of personal lubricants. Similarly, lysed blood, protein, and necrotic debris present a challenge in terms of negative cell transference caused by a clogged filter. In the current study, the authors evaluated the potential use of a modified SurePath reprocessing technique to decrease the frequency of unsatisfactory specimens.

METHODS

An aliquot for human papillomavirus testing was set aside and the remaining specimen in the ThinPrep vial was submitted for sedimentation. A methanol wash was performed using preservative that was added to the remaining sediment. The specimen was vortexed and a protein wash of Tris‐buffered deionized water was added before processing. The specimens were stained using the ThinPrep staining protocol. Both the original specimen and the reprocessed specimens were manually reviewed by 1 cytotechnologist and 2 pathologists to determine specimen adequacy.

RESULTS

A total of 1937 ThinPrep Papanicolaou tests were reprocessed and examined. Of these, 1093 (56%) specimens were satisfactory, 624 of which (57%) demonstrated evidence of a transformation zone component. Epithelial cell abnormalities were identified in 116 specimens (10.6%), including 11 high‐grade squamous intraepithelial lesion specimens (1.0%); 5 specimens with a classification of atypical squamous cells, cannot rule out a high‐grade lesion (0.5%); 21 low‐grade squamous intraepithelial lesion specimens (1.9%); and 79 specimens classified as atypical squamous cells of undetermined significance (7.2%).

CONCLUSIONS

The modified SurePath processing technique was adept at handling nearly all of the challenges that biological and environmental conditions (blood, protein, lubricant, etc) present in liquid‐based filter preparations. A total of 1093 (56%) of 1937 unsatisfactory ThinPrep Papanicolaou tests were converted to a satisfactory state, resulting in 116 abnormalities (10.6%) being diagnosed that otherwise would have gone undetected. Cancer (Cancer Cytopathol) 2014;122:343–348. © 2014 American Cancer Society.
Increased neuronal expression of neurokinin‐1 receptor and stimulus‐evoked internalization of the receptor in the rostral ventromedial medulla of the rat after peripheral inflammatory injury
Authors: Hamity Marta V. , Walder Roxanne Y. , Hammond Donna L.
Published: February 2014

This study examined possible mechanisms by which Substance P (Sub P) assumes a pronociceptive role in the rostral ventromedial medulla (RVM) under conditions of peripheral inflammatory injury, in this case produced by intraplantar (ipl) injection of complete Freund's adjuvant (CFA). In saline‐ and CFA‐treated rats, neurokinin‐1 receptor (NK1R) immunoreactivity was localized to neurons in the RVM. Four days after ipl injection of CFA, the number of NK1R‐immunoreactive neurons in the RVM was increased by 30%, and there was a concomitant increase in NK1R‐immunoreactive processes in CFA‐treated rats. Although NK1R immunoreactivity was increased, tachykinin‐1 receptor (Tacr1) mRNA was not increased in the RVM of CFA‐treated rats. To assess changes in Sub P release, the number of RVM neurons that exhibited NK1R internalization was examined in saline‐ and CFA‐treated rats following noxious heat stimulation of the hind paws. Only CFA‐treated rats that experienced noxious heat stimulation exhibited a significant increase in the number of neurons showing NK1R internalization. These data suggest that tonic Sub P release is not increased as a simple consequence of peripheral inflammation, but that phasic or evoked release of Sub P in the RVM is increased in response to noxious peripheral stimulation in a persistent inflammatory state. These data support the proposal that an upregulation of the NK1R in the RVM, as well as enhanced release of Sub P following noxious stimulation, underlie the pronociceptive role of Sub P under conditions of persistent inflammatory injury. J. Comp. Neurol. 522:3037–3051, 2014. © 2014 Wiley Periodicals, Inc.
Abnormal lateral geniculate nucleus and optic chiasm in human albinism
Authors: Mcketton Larissa , Kelly Krista R. , Schneider Keith A.
Published: February 2014

Our objective was to measure how the misrouting of retinal ganglion cell (RGC) fibers affects the organization of the optic chiasm and lateral geniculate nuclei (LGN) in human albinism. We compared the chiasmal structures and the LGN in both pigmented controls and patients with albinism by using high‐resolution structural magnetic resonance imaging (MRI). We studied 12 patients with oculocutaneous albinism and 12 age‐matched pigmented controls. Using a 3T MRI scanner, we acquired a T1‐weighted three‐dimensional magnetization‐prepared rapid gradient‐echo (MPRAGE) image of the whole brain, oriented so that the optic nerves, chiasm, and tracts were in the same plane. We acquired multiple proton density‐weighted images centered on the thalamus and midbrain, and averaged them to increase the signal, enabling precise manual tracing of the anatomical boundaries of the LGN. Albinism patients exhibited significantly smaller diameters of the optic nerves, chiasm and tracts, and optic chiasm and LGN volume compared with controls (P < 0.001 for all). The reductions in chiasmal diameters in the albinism compared with the control group can be attributed to the abnormal crossing of optic fibers and the reduction of RGCs in the central retina. The volume of the LGN devoted to the center of the visual field may be reduced in albinism due to fewer RGCs representing the area where the fovea would normally lie. Our data may be clinically useful in addressing how genetic deficits compromise proper structural and functional development in the brain. J. Comp. Neurol. 522:2680–2687, 2014. © 2014 Wiley Periodicals, Inc.
Slow‐pressor angiotensin II hypertension and concomitant dendritic NMDA receptor trafficking in estrogen receptor β–containing neurons of the mouse hypothalamic paraventricular nucleus are sex and age dependent
Authors: Marques‐Lopes Jose , Van Kempen Tracey , Waters Elizabeth M. , Pickel Virginia M. , Iadecola Costantino , Milner Teresa A.
Published: February 2014

The incidence of hypertension increases after menopause. Similar to humans, “slow‐pressor” doses of angiotensin II (AngII) increase blood pressure in young males, but not in young female mice. However, AngII increases blood pressure in aged female mice, paralleling reproductive hormonal changes. These changes could influence receptor trafficking in central cardiovascular circuits and contribute to hypertension. Increased postsynaptic N‐methyl‐D‐aspartate (NMDA) receptor activity in the hypothalamic paraventricular nucleus (PVN) is crucial for the sympathoexcitation driving AngII hypertension. Estrogen receptors β (ERβs) are present in PVN neurons. We tested the hypothesis that changes in ovarian hormones with age promote susceptibility to AngII hypertension, and influence NMDA receptor NR1 subunit trafficking in ERβ‐containing PVN neurons. Transgenic mice expressing enhanced green fluorescent protein (EGFP) in ERβ‐containing cells were implanted with osmotic minipumps delivering AngII (600 ng/kg/min) or saline for 2 weeks. AngII increased blood pressure in 2‐month‐old males and 18‐month‐old females, but not in 2‐month‐old females. By electron microscopy, NR1‐silver–intensified immunogold (SIG) was mainly in ERβ‐EGFP dendrites. At baseline, NR1‐SIG density was greater in 2‐month‐old females than in 2‐month‐old males or 18‐month‐old females. After AngII infusion, NR1‐SIG density was decreased in 2‐month‐old females, but increased in 2‐month‐old males and 18‐month‐old females. These findings suggest that, in young female mice, NR1 density is decreased in ERβ‐PVN dendrites thus reducing NMDA receptor activity and preventing hypertension. Conversely, in young males and aged females, NR1 density is upregulated in ERβ‐PVN dendrites and ultimately leads to the neurohumoral dysfunction driving hypertension. J. Comp. Neurol. 522:3075–3090, 2014. © 2014 Wiley Periodicals, Inc.
Quantum Conversion Enhancement with TiOx Compact Layers for ITO‐Plastic‐Film‐Based Low‐Temperature‐Processed Dye‐Sensitized Photoelectrodes
Authors: Morita Saori , Ikegami Masashi , Wei Tzu‐Chien , Miyasaka Tsutomu
Published: February 2014

A plastic substrate‐based dye‐sensitized photoelectrode was fabricated with a thin mesoporous titania film prepared on a TiOx‐coated indium tin oxide‐polyethylene naphthalate (ITO‐PEN) substrate by a low‐temperature process. The 3.5 μm‐thick titania film sensitized with an indoline dye (D205) yielded a power conversion efficiency of 5.2 %, with the internal quantum efficiency reaching 100 %.
How Many Molecules are Required to Obtain a Steady Faradaic Current from Mediated Electron Transfer at a Single Nanoparticle on a Supporting Surface?
Authors: Kätelhön Enno , Krause Kay J. , Wolfrum Bernhard , Compton Richard G.
Published: February 2014

We investigate the chronoamperometric noise characteristics of electron‐transfer reactions occurring on single nanoparticles (NPs) and assemblies of well‐separated NPs on a supporting surface. To this end, we combine a formerly described expression for the steady‐state current of a single particle with the shot‐noise model and derive an expression for the signal‐to‐noise ratio as a function of bulk concentration and particle radius. Our findings are supported by random‐walk simulations, which closely match the analytical results.
Controllable Synthesis and Peculiar Optical Properties of Lanthanide‐Doped Fluoride Nanocrystals
Authors: Dong Guoping , He Huilin , Pan Qiwen , Chen Gengxu , Xie Junhua , Ma Zhijun , Peng Mingying
Published: February 2014

Yb3+/Tm3+‐codoped NaYF4 nanocrystals with different phases (cubic α and hexagonal β) and morphologies (nanoparticles, nanorods, nanoplates) have been controllably fabricated by a convenient hydrothermal synthesis technique. Up‐conversion emission peaks were observed at λ=450, 475, 645, and 700 nm, which were assigned to the 1D2–3F4, 1G4–3H6, 1G4–3F4, and 3F2–3H6 transitions of Tm3+ ions, respectively. By using a homemade detection system, the anisotropic polarized emission properties of individual NaYF4:Yb, Tm nanorods and nanoplates were investigated. The results indicated that the polarization emission ratio, ρ, of the 1G4–3F4 emission of individual NaYF4:Yb,Tm nanorods was 0.18, whereas the anisotropic polarization emission of individual NaYF4:Yb,Tm nanoplates could be neglected; this indicated that the size and morphology of the nanocrystal played an important role in the polarized emission properties. Investigation into the mechanism indicated that the dielectric mismatch was not the predominant mechanism for the polarized emission of individual NaYF4:Yb,Tm nanorods. The as‐prepared NaYF4:Yb,Tm nanocrystals, with controllable morphology and anisotropic polarized emission properties, are expected to be widely applied as polarized light resources, bio‐labels, photodetectors, and so forth.
Chirality Transfer in Magnetic Coordination Complexes Monitored by Vibrational and Electronic Circular Dichroism
Authors: Wu Tao , Zhang Xiao‐Peng , You Xiao‐Zeng , Li Yi‐Zhi , Bouř Petr
Published: February 2014

Magnetic coordination complexes based on Schiff bases are promising new molecular materials for electronics. Two μ‐oxo FeIII dimeric complexes of enantiomers of Schiff base ligands (N,N′‐(1R,2R)‐1,2‐diphenylethylenebis(salicylideneimine) (H2salphen‐R, 1 a) and N,N′‐(1S,2S)‐1,2‐diphenylethylenebis(salicylideneimine) (H2salphen‐S, 1 b)) were synthesized; further reaction with 4‐salicylideneamino‐1,2,4‐triazole (Hsaltrz) led to enantiomers of two one‐dimensional (1D) FeIII coordination complexes. The structures of these complexes were determined by X‐ray diffraction. Magnetic susceptibility measurements revealed that μ‐oxo dimeric complexes displayed strong antiferromagnetic coupling, whereas the 1D complexes exhibited paramagnetic behavior. The chirality of the Schiff bases transferred to macromolecular chirality of the complexes, which could be monitored by both vibrational and electronic circular dichroism (CD) spectroscopic methods. The macroscopic handedness was manifested in CD signals attributed to exciton coupling between the ligands. Thus, the chiral spectroscopies were useful to probe the chirality of the complexes, their structure, and the polymerization degree.
Crystallization of MIGe2(PO4)3 (MI – Na, K, Ag) from molten phosphate media
Authors: Terebilenko K. V. , Slobodyanik N. S. , Ogorodnyk I.V. , Baumer V. N.
Published: February 2014

A number of NASICON‐related MIGe2(PO4)3 (MI – Na, K, Ag) have been prepared using a high‐temperature solution method in the molten system MI‐Ge‐P‐O (MI – Na, K) based on the solubility data for GeO2 at 1123 K for the Na‐P‐O system and 1173 K for the K‐P‐O one. The single crystals of AgGe2(PO4)3 were obtained after crystallization of a melt with Ag/P = 1.4. It crystallizes in the trigonal system, space group R‐3, cell parameters a = 8.06340(1) Å, c = 21.8385(4) Å, Z = 6. The framework is built up from two GeO6 units that are isolated from each other by PO4 tetrahedra to form the main building block of the structure [Ge2(PO4)3]−. Two types of silver cations M1 and M2 are found to have different coordination requirements shown by the bond valence sum calculations.
Self‐assembly of a luminescent Zn(II) carboxylate with the diamondoid topology
Authors: Zhang Tian , Wang Gui‐Xia , Xue Li‐ping
Published: February 2014

A new coordination polymer [Zn(tdc)(bimb)]n (1) (H2tdc = 3,4‐thiophenedicarboxylic acid, bimb = 1,4‐bis(imidazol‐1ˊ‐yl)butane) has been synthesized under hydrothermal condition. X‐ray single‐crystal diffraction determination reveals that 1 crystallizes in the space group P212121 of orthorhombic crystal system: a = 10.517(2), b = 10.889(2), c = 15.206(3) Å. This compound features a 3D network which can be rationalized as a 4‐connected diamondoid net. Moreover, thermal and photoluminescent properties for 1 have also been investigated.
Gas Separation Performance of Carbon Molecular Sieve Membranes Based on 6FDA‐mPDA/DABA (3:2) Polyimide
Authors: Qiu Wulin , Zhang Kuang , Li Fuyue Stephanie , Zhang Ke , Koros William J.
Published: February 2014

6FDA‐mPDA/DABA (3:2) polyimide was synthesized and characterized for uncross‐linked, thermally crosslinked, and carbon molecular sieve (CMS) membranes. The membranes were characterized with thermogravimetric analysis, FTIR spectroscopy, wide‐angle X‐ray diffraction, and gas permeation tests. Variations in the d spacing, the formation of pore structures, and changes in the pore sizes of the CMS membranes were discussed in relation to pyrolysis protocols. The uncross‐linked polymer membranes showed high CO2/CH4 selectivity, whereas thermally crosslinked membranes exhibited significantly improved CO2 permeability and excellent CO2 plasticization resistance. The CMS membranes showed even higher CO2 permeability and CO2/CH4 selectivity. An increase in the pyrolysis temperature resulted in CMS membranes with lower gas permeability but higher selectivity. The 550 °C pyrolyzed CMS membranes showed CO2 permeability as high as 14 750 Barrer with CO2/CH4 selectivity of approximately 52. Even 800 °C pyrolyzed CMS membranes still showed high CO2 permeability of 2610 Barrer with high CO2/CH4 selectivity of approximately 118. Both polymer membranes and the CMS membranes are very attractive in aggressive natural gas purification applications.
Sustainable Production of Green Feed from Carbon Dioxide and Hydrogen
Authors: Landau Miron V. , Vidruk Roxana , Herskowitz Moti
Published: February 2014

Carbon dioxide hydrogenation to form hydrocarbons was conducted on two iron‐based catalysts, prepared according to procedures described in the literature, and on a new iron spinel catalyst. The CO2 conversion measured in a packed‐bed reactor was limited to about 60 % because of excessive amounts of water produced in this process. Switching to a system of three packed‐bed reactors in series with interim removal of water and condensed hydrocarbons increased CO2 conversion to as much as 89 %. The pure spinel catalyst displayed a significantly higher activity and selectivity than those of the other iron catalysts. This process produces a product called green feed, which is similar in composition to the product of a high‐temperature, iron‐based Fischer–Tropsch process from syngas. The green feed can be readily converted into renewable fuels by well‐established technologies.
Combinatorial Atmospheric Pressure CVD of a Composite TiO2/SnO2 Thin Film
Authors: Sathasivam Sanjayan , Kafizas Andreas , Ponja Sapna , Chadwick Nicholas , Bhachu Davinder S. , Bawaked Salem M. , Obaid Abdullah Y. , Al‐Thabaiti Shaeel , Basahel Sulaiman N. , Carmalt Claire J. , Parkin Ivan P.
Published: February 2014

Combinatorial atmospheric pressure (cAP)CVD is used to deposit a film of graded composition from mainly TiO2 to TiO2/SnO2 to mainly SnO2. This is the first cAPCVD study of a TiO2/SnO2 system. The thin film is characterized using a range of techniques such as X‐ray diffraction (XRD), wavelength dispersive X‐ray (WDX) spectroscopy, X‐ray photoelectron spectroscopy (XPS), scanning electron microscopy (SEM), and ultra violet‐visible (UV‐vis) spectroscopy. It is found that, at various positions on the film, there are intimate compositions of TiO2 and SnO2. The photocatalytic activity is examined via the degradation of a Resazurin‐based ‘intelligent ink’ under 365 nm wavelength irradiation. The change in the concentration of the dye can be monitored by digital imaging alone. The results show how TiO2‐rich regions are photocatalytically active, producing a maximum formal quantum yield of 3.32 × 10−4 molecules per absorbed photon. The sheet resistance is determined using a four‐point probe via the van der Pauw method. The conductivity is highest in the SnO2‐rich and thicker regions of the film, however some of the intimate composite regions of TiO2/SnO2 show both conductivity and photocatalytic activity.
Aluminizing of Nickel Alloys by CVD. The Effect of HCl Flow
Authors: Wierzba Bartek , Tkacz‐Śmiech Katarzyna , Nowotnik Andrzej , Dychtoń Kamil
Published: February 2014

The solid‐state diffusion in binary and ternary systems is overall treated and modeled using the bi‐velocity method. The mathematical formulation is given, and the boundary conditions discussed. The model allows the calculation of concentration profiles, spatial distribution of the entropy production rate, and diffusion path. The last two can be used to identify the phases present in the diffusion zone of the ternary system, and determine the thicknesses of the respective layers. The model is applied for the first time to simulate diffusion during aluminization of nickel and its super‐alloys, MAR‐M200 + Hf and CMSX‐4, and the predictions are compared with the results of the experiments performed by the authors. The results give a new quantitative explanation of the high‐active and low‐active regimes of aluminization. It is, in particular, confirmed that the high‐active and low‐active regimes of nickel aluminization can be carried out by a variation of the HCl/H2 flow ratio. The most important, and a brand new, result concerns the entropy production rate. It is shown that its maxima coincidence with the two‐phase zone boundaries in real space, which gives new insight into the modeling of the diffusion in ternary systems.
Combining network coding and compressed sensing for error correction in wireless sensor networks
Authors: Chen Siguang , Wu Meng , Wang Kun , Sun Zhixin , Lu Weifeng
Published: February 2014

As the spatial and temporal correlations of sensor readings are common in wireless sensor networks, motivated by these features and the drawbacks of network coding (NC), we introduce compressed sensing (CS) into NC scheme and construct a cooperating coding mechanism, which performs over different data fields with a compatible transformation measure for the combination of NC and CS. This cooperating coding scheme can reduce the amount of redundant information transmission significantly, because the temporal and spatial correlations are explored fully. Meanwhile, the erasures and errors are considered simultaneously in relay transmission process; a NC decoding for error control is proposed to correct the erasures and errors. Although the decoding error of NC is existent, this error can be further reduced by the reconstruction process of CS; as a result, the relative recovery error is small enough in the sink. Finally, the reliability and performance analyses confirm that the proposed cooperating coding scheme obtains considerable compression gain as compared with conventional coding scheme of NC and transmits information reliably with high recovery precision. Copyright © 2014 John Wiley & Sons, Ltd.
Placentophagia in weanling female laboratory rats
Authors: Harding Kaitlyn M. , Lonstein Joseph S.
Published: February 2014

Placentophagia is common in parturient mammals and offers physiological and behavioral advantages for mothers. In natural environments, weanlings are often present during the birth of younger siblings, but it is unknown if weanling rats are placentophagic or prefer placenta over other substances. To examine this, primiparous rats were remated during the postpartum estrus and their weanling daughters remained in the natal nest during their mother's next parturition. Continuous observation revealed that 58% of weanlings were placentophagic. To determine if this placentophagia occurs away from parturient mothers, weanling females still living in their natal nest were offered placenta, liver, or cake frosting in a novel chamber. They ingested more placenta and liver than frosting. Thus, many weanling female laboratory rats are placentophagic during the birth of younger siblings but do not selectively prefer placenta when tested outside their natal nest. Consequences of placentophagia by weanling female rats are unknown, but it may promote their alloparenting or later postpartum mothering. © 2014 Wiley Periodicals, Inc. Dev Psychobiol 56: 1290–1299, 2014.
Human‐aided admixture may fuel ecosystem transformation during biological invasions: theoretical and experimental evidence
Authors: Molofsky Jane , Keller Stephen R. , Lavergne Sébastien , Kaproth Matthew A. , Eppinga Maarten B.
Published: February 2014

Biological invasions can transform our understanding of how the interplay of historical isolation and contemporary (human‐aided) dispersal affects the structure of intraspecific diversity in functional traits, and in turn, how changes in functional traits affect other scales of biological organization such as communities and ecosystems. Because biological invasions frequently involve the admixture of previously isolated lineages as a result of human‐aided dispersal, studies of invasive populations can reveal how admixture results in novel genotypes and shifts in functional trait variation within populations. Further, because invasive species can be ecosystem engineers within invaded ecosystems, admixture‐induced shifts in the functional traits of invaders can affect the composition of native biodiversity and alter the flow of resources through the system. Thus, invasions represent promising yet under‐investigated examples of how the effects of short‐term evolutionary changes can cascade across biological scales of diversity. Here, we propose a conceptual framework that admixture between divergent source populations during biological invasions can reorganize the genetic variation underlying key functional traits, leading to shifts in the mean and variance of functional traits within invasive populations. Changes in the mean or variance of key traits can initiate new ecological feedback mechanisms that result in a critical transition from a native ecosystem to a novel invasive ecosystem. We illustrate the application of this framework with reference to a well‐studied plant model system in invasion biology and show how a combination of quantitative genetic experiments, functional trait studies, whole ecosystem field studies and modeling can be used to explore the dynamics predicted to trigger these critical transitions.
Guidelines for a priori grouping of species in hierarchical community models
Authors: Pacifici Krishna , Zipkin Elise F. , Collazo Jaime A. , Irizarry Julissa I. , DeWan Amielle
Published: February 2014

Recent methodological advances permit the estimation of species richness and occurrences for rare species by linking species‐level occurrence models at the community level. The value of such methods is underscored by the ability to examine the influence of landscape heterogeneity on species assemblages at large spatial scales. A salient advantage of community‐level approaches is that parameter estimates for data‐poor species are more precise as the estimation process “borrows” from data‐rich species. However, this analytical benefit raises a question about the degree to which inferences are dependent on the implicit assumption of relatedness among species. Here, we assess the sensitivity of community/group‐level metrics, and individual‐level species inferences given various classification schemes for grouping species assemblages using multispecies occurrence models. We explore the implications of these groupings on parameter estimates for avian communities in two ecosystems: tropical forests in Puerto Rico and temperate forests in northeastern United States. We report on the classification performance and extent of variability in occurrence probabilities and species richness estimates that can be observed depending on the classification scheme used. We found estimates of species richness to be most precise and to have the best predictive performance when all of the data were grouped at a single community level. Community/group‐level parameters appear to be heavily influenced by the grouping criteria, but were not driven strictly by total number of detections for species. We found different grouping schemes can provide an opportunity to identify unique assemblage responses that would not have been found if all of the species were analyzed together. We suggest three guidelines: (1) classification schemes should be determined based on study objectives; (2) model selection should be used to quantitatively compare different classification approaches; and (3) sensitivity of results to different classification approaches should be assessed. These guidelines should help researchers apply hierarchical community models in the most effective manner.
Divergent warning patterns contribute to assortative mating between incipient Heliconius species
Authors: Merrill Richard M. , Chia Audrey , Nadeau Nicola J.
Published: February 2014

Theoretical models suggest that traits under divergent ecological selection, which also contribute to assortative mating, will facilitate speciation with gene flow. Evidence for these so‐called “magic traits” now exists across a range of taxa. However, their importance during speciation will depend on the extent to which they contribute to reproductive isolation. Addressing this requires experiments to determine the exact cues involved as well as estimates of assortative mating in the wild. Heliconius butterflies are well known for their diversity of bright warning color patterns, and their amenability to experimental manipulation has provided an excellent opportunity to test their role in reproductive isolation. Here, we reveal that divergent color patterns contribute to mate recognition between the incipient species Heliconius himera and H. erato, a taxon pair for which assortative mating by color pattern has been demonstrated among wild individuals: First, we demonstrate that males are more likely to attempt to mate conspecific females; second, we show that males are more likely to approach pinned females that share their own warning pattern. These data are valuable as these taxa likely represent the early stages of speciation, but unusually also allow comparisons with rates of interbreeding between divergent ecologically relevant phenotypes measured in the wild.
ESC Working Group on Myocardial Function Position Paper: how to study the right ventricle in experimental models
Authors: Leite‐Moreira Adelino F. , Lourenço André P. , Balligand Jean‐Luc , Bauersachs Johann , Clerk Angela , De Windt Leon J. , Heymans Stephane , Hilfiker‐Kleiner Denise , Hirsch Emilio , Iaccarino Guido , Kaminski Karol A. , Knöll Ralph , Mayr Manuel , Tarone Guido , Thum Thomas , Tocchetti Carlo G.
Published: February 2014

The right ventricle has become an increasing focus in cardiovascular research. In this position paper, we give a brief overview of the specific pathophysiological features of the right ventricle, with particular emphasis on functional and molecular modifications as well as therapeutic strategies in chronic overload, highlighting the differences from the left ventricle. Importantly, we put together recommendations on promising topics of research in the field, experimental study design, and functional evaluation of the right ventricle in experimental models, from non‐invasive methodologies to haemodynamic evaluation and ex vivo set‐ups.
Sex‐specific cardiovascular structure and function in heart failure with preserved ejection fraction
Authors: Gori Mauro , Lam Carolyn S. P. , Gupta Deepak K. , Santos Angela B. S. , Cheng Susan , Shah Amil M. , Claggett Brian , Zile Michael R. , Kraigher‐Krainer Elisabeth , Pieske Burkert , Voors Adriaan A. , Packer Milton , Bransford Toni , Lefkowitz Martin , McMurray John J. V. , Solomon Scott D. ,   for the PARAMOUNT Investigators
Published: February 2014

Aims

Women are more likely to develop heart failure with preserved ejection fraction (HFpEF) than men. We studied the relationship between sex and cardiovascular structure and function in patients with HFpEF.

Methods and results

The study included 279 participants from the PARAMOUNT study (57% women) with analysable baseline echocardiograms (mean age 71 years, 94% hypertensive, 38% diabetic). We assessed sex‐based differences in baseline clinical characteristics and measures of cardiovascular structure/function. Coronary artery disease was less common in women than in men. Women were more obese and symptomatic, and less likely to have albuminuria. Women had higher indexed left ventricular (LV) wall thicknesses, worse diastolic function (lower E′, P = 0.002; higher E/E′, P < 0.001), while LV mass and LV volumes indexed for height2.7 were similar. Nonetheless, female sex was associated with a trend towards higher prevalence of abnormal LV geometry (defined as concentric hypertrophy, or eccentric hypertrophy, or concentric remodelling) at baseline (unadjusted P = 0.028, adjusted P = 0.056) and 12 weeks' follow up (unadjusted P = 0.001, adjusted P = 0.006), but not at 36 weeks' follow up (unadjusted P = 0.81, adjusted P = 0.99). Despite higher LV ejection fraction in women, global LV strain was similar between the sexes, while Tissue Doppler Imaging S′ mitral velocity was lower in women. Both LV diastolic and systolic stiffness were higher in women than men (P < 0.001), even adjusting for LV concentricity and clinical covariates. We observed no sex differences in systolic arterial–LV coupling, as women also had higher absolute arterial elastance compared with men, although this difference was not significant after adjusting for height2.7.

Conclusion

More pronounced diastolic dysfunction may contribute to the greater predisposition for HFpEF in women compared with men.
Rational Design of Ligand Precursors to Prepare Abnormal (Mesoionic) and Normal Carbene Complexes and Zwitterionic CX‐Type Palladacycles (X = C, N)
Authors: Chen Shih‐Ji , Lin Yuan‐Deng , Chiang Yen‐Hsin , Lee Hon Man
Published: February 2014

The preparation of a series of ligand precursors that feature imidazo[1,2‐a]pyridine and amido functional groups is reported. The reactions between the new ligand precursors, pyridine, and palladium acetate in DMF afforded monodentate PdII abnormal (mesoionic) carbene complexes. An isomeric PdII normal carbene complex with a formally identical steric environment to that of the abnormal carbene counterpart was also prepared. The isomeric pairs were characterized by X‐ray structural studies. Under different complexation conditions, in which PdCl2 was employed as metal precursor, a zwitterionic CC‐type palladacycle formed by the C–H activation at the ortho‐N‐phenyl and methylene carbon atoms was obtained. The use of a similar ligand precursor with an NH instead of an NMe group produced a zwitterionic palladalactam complex. In contrast to the previous work in the literature, owing to the rigidity of the fused heterocyclic ring, the palladalactam complex did not undergo intramolecular proton transfer through the coordinated N atom. Overall, we demonstrated that proper modification of the structures of ligand precursors and complexation conditions allowed us to obtain a full range of intriguing PdII complexes including normal and abnormal carbene complexes, and zwitterionic palladalactam and CC‐type palladacycles by means of A–H bond (A = N, C) activations.
Bridging the Gap: Attractive 3c–4e Interactions in peri‐Substituted Acenaphthylenes
Authors: Diamond Louise M. , Knight Fergus R. , Athukorala Arachchige Kasun S. , Randall Rebecca A. M. , Bühl Michael , Slawin Alexandra M. Z. , Woollins J. Derek
Published: February 2014

A series of peri‐substituted acenaphthylenes that contain mixed halogen–chalcogen functionalities at the 5,6‐positions in 1–6 [Acenapyl[X](EPh) (Acenapyl = acenaphthylene‐5,6‐diyl; X = Br, I; E = S, Se, Te)] and chalcogen–chalcogen moieties in 7–11 [Acenap(EPh)(E′Ph) (Acenap = acenaphthene‐5,6‐diyl; E/E′ = S, Se, Te)] have been prepared from their corresponding acenaphthene analogues A1–A11 by utilising 2,3‐dichloro‐5,6‐dicyano‐1,4‐benzoquinone (DDQ) for the dehydrogenation of the ethane backbone. The related dihalide compounds 13 and 14 Acenapyl[XX′] (XX′ = BrBr, II) have also been prepared by following a similar procedure, and 1,2,5,6‐tetrabromo‐1,2‐dihydroacenaphthylene A0 was prepared as an intermediate by following an alternative route to 13. The series of acenaphthylene compounds have remarkably similar molecular structures to their acenaphthene counterparts; they exhibit an expected increase in peri separation as heavier congeners occupy the close peri positions. The presence of the ethene bridge, however, naturally compresses the nearest bay angle as it increases the splay of the exocyclic peri atoms, thereby resulting in a minor increase in separation relative to equivalent acenaphthenes. The structures of 1–11, 13 and 14 are discussed and compared with previously reported analogous naphthalene and acenaphthene compounds. Similar to acenaphthene derivatives, aromatic ring conformations and the location of p‐type lone pairs influences the geometry of the peri region. Under appropriate geometric conditions, quasi‐linear three‐body CPh–E···Z (E = Te, Se, S; Z = Br/E) fragments provide an attractive component for the E···Z interaction. DFT studies confirm the onset of formation of three‐center, four‐electron bonding, similar in extent to that observed in analogous acenaphthenes, despite an increase in the peri distances.
Baker's‐Yeast‐Mediated Reduction of Sulfur‐Containing Compounds
Authors: Deasy Rebecca E. , Maguire Anita R.
Published: February 2014

Both the efficiency and the stereoselectivity in baker's‐yeast‐mediated reduction of ketones are strongly influenced by both the presence and the position of sulfur substituents, or indeed by the use of sulfur‐containing additives. Interestingly the oxidation level of the sulfur substituent has a powerful impact on the outcome of the yeast reduction. It is apparent that use of the sulfone moiety as a substituent to influence the efficiency and stereoselectivity in ketone reduction is substantially more effective than use of the analogous sulfide and sulfoxide moieties.