bluuebunny/crossref_metadata_2025 huggingface dataset:
Immittance Data Validation by Kramers‐Kronig Relations – Derivation and Implications
Authors: Malkow T.
Published: August 2017

Explicitly based on causality, linearity (superposition) and stability (time invariance) and implicit on continuity (consistency), finiteness (convergence) and uniqueness (single valuedness) in the time domain, Kramers‐Kronig (KK) integral transform (KKT) relations for immittances are derived as pure mathematical constructs in the complex frequency domain using the two‐sided (bilateral) Laplace integral transform (LT) reduced to the Fourier domain for sufficiently rapid exponential decaying, bounded immittances. Novel anti KK relations are also derived to distinguish LTI (linear, time invariant) systems from non‐linear, unstable and acausal systems. All relations can be used to test KK transformability on the LTI principles of linearity, stability and causality of measured and model data by Fourier transform (FT) in immittance spectroscopy (IS). Also, integral transform relations are provided to estimate (conjugate) immittances at zero and infinite frequency particularly useful to normalise data and compare data. Also, important implications for IS are presented and suggestions for consistent data analysis are made which generally apply likewise to complex valued quantities in many fields of engineering and natural sciences.
Selective Ion Exchange and Photocatalysis by Zeolite‐Like Semiconducting Chalcogenide
Authors: Chen Xitong , Bu Xianhui , Lin Qipu , Mao Chengyu , Zhai Quan‐Guo , Wang Yuan , Feng Pingyun
Published: August 2017

The development of novel photocatalysts usually centers on features such as band structures, various nano‐, micro‐, or macro‐forms, and composites in efforts to tune their light absorption and charge separation efficiency. In comparison, the selectivity of photocatalysts with respect to features of reactants such as size and charge has received much less attention, in part due to the difficulty in designing semiconducting photocatalysts with uniform pore size. Here, we use crystalline porous chalcogenides as a platform to probe reactant selectivity in photocatalytic processes. The 3‐in‐1 integration of high surface area, uniform porosity, and favorable band structures in such chalcogenides makes them excellent candidates for efficient and selective photocatalytic processes. We show that their photocatalytic activity and selectivity are closely related to their differing affinity and selectivity for different guest species. In particular, unlike common solid‐state photocatalysts with neutral framework, the anionic nature of the porous chalcogenide framework used here endows them with a high degree of selectivity for cationic species in both guest exchange and closely coupled photocatalytic transformation of such guests. Another interesting discovery is the observation of an unusual ion exchange process involving a transient state of over‐saturation of exchanged ions, which can be explained by a transition from an initially kinetically controlled process to a subsequent thermodynamically controlled one. This work is part of ongoing efforts to contribute to the development of a new generation of crystalline porous photocatalysts with custom‐designed selectivity for various reactants or products.
Effects of Fluorophore Attachment on Protein Conformation and Dynamics Studied by spFRET and NMR Spectroscopy
Authors: Sánchez‐Rico Carolina , Voith von Voithenberg Lena , Warner Lisa , Lamb Don C. , Sattler Michael
Published: August 2017

Fluorescence‐based techniques are widely used to study biomolecular conformations, intra‐ and intermolecular interactions, and conformational dynamics of macromolecules. Especially for fluorescence‐based single‐molecule experiments, the choice of the fluorophore and labeling position are highly important. In this work, we studied the biophysical and structural effects that are associated with the conjugation of fluorophores to cysteines in the splicing factor U2AF65 by using single pair Förster resonance energy transfer (FRET) and nuclear magnetic resonance (NMR) spectroscopy. It is shown that certain acceptor fluorophores are advantageous depending on the experiments performed. The effects of dye attachment on the protein conformation were characterized using heteronuclear NMR experiments. The presence of hydrophobic and aromatic moieties in the fluorophores can significantly affect the conformation of the conjugated protein, presumably by transient interactions with the protein surface. Guidelines are provided for carefully choosing fluorophores, considering their photophysical properties and chemical features for the design of FRET experiments, and for minimizing artifacts.
Allenols versus Allenones: Rhodium‐Catalyzed Regiodivergent and Tunable Allene Reactivity with Triazoles
Authors: Alcaide Benito , Almendros Pedro , Cembellín Sara , Martínez del Campo Teresa , Palop Guillermo
Published: August 2017

2‐Pyrrolines and 6‐oxo‐hexa‐2,4‐dienals have been prepared through the divergent reactions of 1‐benzenesulfonyl‐4‐aryl‐1,2,3‐triazoles with functionalized allenes. The rhodium‐catalyzed reactions between allenols and 1‐benzenesulfonyl‐4‐aryl‐1,2,3‐triazoles yielded 2‐pyrrolines. This transformation is compatible with the presence of aliphatic, aromatic, heterocyclic, amide, and halogen functional groups. Interestingly, a reactivity switch took place when the allene‐tethered alcohol substrate was replaced by its ketone counterpart. When the rhodium‐catalyzed reaction of 1‐benzenesulfonyl‐4‐phenyl‐1,2,3‐triazole was performed with allenones, acyclic 6‐oxo‐hexa‐2,4‐dienals were stereoselectively formed as (2Z,4E) isomers.
Preparation of Supported Palladium Catalysts using Deep Eutectic Solvents
Authors: Iwanow Melanie , Finkelmeyer Jasmin , Söldner Anika , Kaiser Manuela , Gärtner Tobias , Sieber Volker , König Burkhard
Published: August 2017

Deep eutectic solvents (DESs) dissolve metal salts or oxides and are used as solvent and carbon source for the preparation of supported palladium catalysts. After dissolving of the palladium salt in the DES, the pyrolysis of the mixture under nitrogen atmosphere yields catalytically active palladium on supporting material composed of carbon, nitrogen and oxygen (CNO) by a simple single step preparation method without further activation. The catalysts were characterized by scanning electron microscopy (SEM) and X‐ray photoelectron spectroscopy (XPS), X‐ray diffraction (XRD), Brunauer–Emmett–Teller (BET) and CHNS/O elementary analysis. The amount of functional groups on the surface of the supporting material was determined by Boehm titrations. Moreover, the activity of the prepared catalysts was evaluated in the hydrogenation of linear alkenes and compared with a commercial Pd/C catalyst.
Copper‐Containing Nitrite Reductase Employing Proton‐Coupled Spin‐Exchanged Electron‐Transfer and Multiproton Synchronized Transfer to Reduce Nitrite
Authors: Qin Xin , Deng Li , Hu Caihong , Li Li , Chen Xiaohua
Published: August 2017

The possible catalytic mechanism of the reduction of nitrite by copper‐containing nitrite reductases (CuNiRs) is examined by using the M06 function according to two copper models, which include type‐one copper (T1Cu) and type‐two copper (T2Cu) sites. Examinations confirm that the protonation of two residues, His255 and Asp98, near the T2Cu site, can modulate the redox states of T1Cu and T2Cu, but cannot directly cause electron transfer from T1Cu to T2Cu. The electron hole remains at the T2Cu site when only one residue, His255 or Asp98, is protonated. However, the hole resides at the T1Cu site when both His255 and Asp98 are protonated. Then, the first protonation of nitrite takes place through indirect proton transfer from protonated His255 through the bridging H2O and Asp98 with three protons moving together, which cannot cause the cleavage of the HO−NO bond. Subsequently, the substrate is required to obtain another proton from reprotonated His255 through the bridging H2O. The reprotonation of nitrite induces the generation of nitric oxide (NO) and H2O at the T2Cu site through a special double‐proton‐coupled spin‐exchanged electron‐transfer mechanism with indirect proton transfer from His255 to the substrate, a beta‐electron of T2CuI shift to the NO cation, and the remaining alpha‐electron changing spin direction at the same time. These results may provide useful information to better understand detailed proton‐/electron‐transfer reactions for the catalytic processes of CuNiR.
A Recyclable Metal–Organic Framework as a Dual Detector and Adsorbent for Ammonia
Authors: Gładysiak Andrzej , Nguyen Tu N. , Navarro Jorge A. R. , Rosseinsky Matthew J. , Stylianou Kyriakos C.
Published: August 2017

Recyclable materials for simultaneous detection and uptake of ammonia (NH3) are of great interest due to the hazardous nature of NH3. The structural versatility and porous nature of metal–organic frameworks (MOFs) make them ideal candidates for NH3 capture. Herein, the synthesis of a water‐stable and porous 3‐dimensional CuII‐based MOF (SION‐10) displaying a ship‐in‐a‐bottle structure is reported; the pores of the host SION‐10 framework accommodate mononuclear CuII‐complexes. SION‐10 spontaneously uptakes NH3 as a result of two concurrent mechanisms: chemisorption due to the presence of active CuII sites and physisorption (bulk permanent porosity). The color of the material changes from green to blue upon NH3 capture, with the shifts of the UV/Vis absorption bands clearly seen at NH3 concentrations as low as 300 ppm. SION‐10 can be recovered upon immersion of SION‐10⊃NH3 in water and can be further reused for NH3 capture for at least three cycles.
Ultrathin Layers of PdPX (X=S, Se): Two Dimensional Semiconductors for Photocatalytic Water Splitting
Authors: Jing Yu , Ma Yandong , Wang Yu , Li Yafei , Heine Thomas
Published: August 2017

On grounds of first principles calculations we propose two‐dimensional semiconductors, ultrathin mono‐, bi‐ and trilayers of PdPX (X=S, Se), as photocatalysts with band gaps suitable for harvesting the visible part of the solar spectrum and band edge energies matching the electrochemical potentials required for water splitting reaction. Layered bulk palladium phosphochalcogenides, among them the title compounds, have been known since 1971. The cleavage energy of ≈0.6 J m−2 suggests that single and few layer PdPX can be produced by exfoliation from the bulk phase. PdPX monolayer possesses a moderate band gap of 2.12 (1.97) eV for PdPS (PdPSe) and shows high, albeit anisotropic, carrier motilities. Bandgap (and edge) engineering is possible by applying strain (in the range of 1.5∼2.3 eV), and by varying the number of layers, that is, to 1.95(1.80) eV for the bi‐ and 1.75 (1.62) eV for the trilayer, to 1.70 (1.43) eV in the bulk.
Three‐year cytohistological correlation of salivary gland FNA cytology at a tertiary center with the application of the Milan system for risk stratification
Authors: Rohilla Manish , Singh Priya , Rajwanshi Arvind , Gupta Nalini , Srinivasan Radhika , Dey Pranab , Vashishta Rakesh K.
Published: August 2017

BACKGROUND

Fine‐needle aspiration (FNA) cytology of salivary glands is a well‐established technique that plays a critical role in the preoperative diagnosis of lesions. A risk stratification of FNA diagnostic categories has been recently proposed to be useful in reporting. The aims of this study were to evaluate the diagnostic accuracy of salivary gland FNA and to apply the proposed Milan system for reporting salivary gland lesions.

METHODS

A retrospective audit of FNA specimens of salivary gland lesions reported from 2014 to 2016 was performed. A correlation with the follow‐up histopathology, wherever it was available, was performed. The aspirates were then categorized according to the Milan system as follows: nondiagnostic, nonneoplastic, atypical, benign neoplasm, neoplasm of uncertain malignant potential (NUMP), suspicious for malignancy, or positive for malignancy. Furthermore, the risk of malignancy and the risk of high‐grade malignancy were calculated for all diagnostic categories.

RESULTS

A total of 631 salivary gland aspirates were evaluated: 2.2% were nondiagnostic, 55.8% indicated nonneoplastic lesions, and 40.4% indicated neoplastic lesions. Histopathology was available for 94 cases (14.9%). FNA had a sensitivity of 79.4% and a specificity of 98.3% with an overall diagnostic accuracy of 91.4% for differentiating malignant tumors from benign tumors. The overall risk of malignancy was 17.4% for the nonneoplastic category, 100% for the atypical category, 7.3% for the benign neoplasm category, 50% for the NUMP category, and 96% for the positive‐for‐malignancy category.

CONCLUSIONS

Salivary gland FNA continues to have high diagnostic accuracy and is thus helpful for guiding management. Neoplasms with classic cytomorphology are easily diagnosed; however, in difficult cases showing overlapping features, the use of the Milan system could be beneficial. Cancer Cytopathol 2017;125:767‐75. © 2017 American Cancer Society.
Excitation Power Modulates Energy‐Transfer Dynamics in a Supramolecular RuII‐FeII‐RuII Triad
Authors: Kübel Joachim , Wächtler Maria , Dietzek Benjamin
Published: August 2017

Multichromophoric arrays are key to light harvesting in natural and artificial photosynthesis. A trinuclear, symmetric RuII‐FeII‐RuII triad may resemble a light‐harvesting model system in which excitation energy from donor units (Ru‐terpyridine fragments) is efficiently transferred to the acceptor (the Fe‐terpyridine fragment). The photoinduced dynamics after simultaneous excitation of more than a single chromophoric unit (donor/acceptor) at varying excitation fluence is investigated in this contribution. Data suggests that energy transfer is decelerated if the acceptor states (on the FeII unit) are not depopulated fast enough. As a consequence, the lifetime of a high‐lying excited state (centered on either of the RuII units) is prolonged. A kinetic model is suggested to account for this effect. Although the proposed model is specifically adopted to account for the experimental data reported here, it might be generalized to other situations in which multiple energy or electron donors are covalently linked to a single acceptor site, a situation of interest in contemporary artificial photosynthesis.
A Zinc(II) Porous Metal–Organic Framework and Its Morphologically Controlled Catalytic Properties in the Knoevenagel Condensation Reaction
Authors: Wang Jiajia , Wang Xiaoxiao , Xu Haitao , Zhao Xi , Zheng Zhizhong , Xu Zhen‐liang
Published: August 2017

A new metal–organic framework (MOF), {Zn(oba)(3‐bpdh)0.5}∝⋅2 H2O (1 Zn; oba=4,4′‐oxybis(benzoic acid), 3‐bpdh=N,N′‐bis(1‐pyridine‐3‐yl‐ethylidene)hydrazine), was successfully assembled in a solvothermal system. The Zn2+ ion center located in a five‐coordinate environment combined with oba to produce a layer‐like structure, which is again linked with 3‐bpdh to yield a 3D channel framework. MOF 1 Zn microcrystals with different morphologies were synthesized through coordination modulation and solvent‐dependent methods. The effects of the concentration of the modulator, the reaction temperature, and the volume ratio of mixed solvents have been investigated. Furthermore, the catalytic performance in Knoevenagel condensation was studied for different morphologies of 1 Zn microcrystals; this revealed that the MOF microcrystals exhibited excellent and morphology‐dependent catalytic properties.
Dehydrogenase‐Catalyzed Oxidation of Furanics: Exploitation of Hemoglobin Catalytic Promiscuity
Authors: Jia Hao‐Yu , Zong Min‐Hua , Yu Hui‐Lei , Li Ning
Published: August 2017

The catalytic promiscuity of hemoglobin (Hb) was explored for regenerating oxidized nicotinamide cofactors [NAD(P)+]. With H2O2 as oxidant, Hb efficiently oxidized NAD(P)H into NAD(P)+ within 30 min. The new NAD(P)+ regeneration system was coupled with horse liver alcohol dehydrogenase (HLADH) for the oxidation of bio‐based furanics such as furfural and 5‐hydroxymethylfurfural (HMF). The target acids (e.g., 2,5‐furandicarboxylic acid, FDCA) were prepared with moderate‐to‐good yields. The enzymatic regeneration method was applied in l‐glutamic dehydrogenase (DH)‐mediated oxidative deamination of lglutamate and for l‐lactic‐DH‐mediated oxidation of l‐lactate, which furnished α‐ketoglutarate and pyruvate in yields of 97 % and 81 %, respectively. A total turnover number (TTON) of up to approximately 5000 for cofactor and an E factor of less than 110 were obtained in the bi‐enzymatic cascade synthesis of α‐ketoglutarate. Overall, a proof‐of‐concept based on catalytic promiscuity of Hb was provided for in situ regeneration of NAD(P)+ in DH‐catalyzed oxidation reactions.
Insights into the Hydrothermal Stability of Triamine‐Functionalized SBA‐15 Silica for CO2 Adsorption
Authors: Jahandar Lashaki Masoud , Ziaei‐Azad Hessam , Sayari Abdelhamid
Published: August 2017

The hydrothermal stability of triamine‐grafted, large‐pore SBA‐15 CO2 adsorbents was studied by using steam stripping. Following two 3 h cycles of steam regeneration, lower CO2 uptakes, lower CO2/N ratios, and slower adsorption kinetics were observed relative to fresh samples, particularly at the lowest adsorption temperature (25 °C). CO2 adsorption measurements for a selected sample exposed to 48 h of steam stripping depicted that after the initial loss during the first exposure to steam (3–6 h), the adsorptive properties stabilized. For higher adsorption temperatures (i.e., 50 and 75 °C), however, all adsorptive properties remained almost unchanged after steaming, indicating the significance of diffusional limitations. Thermogravimetric analysis and FTIR spectroscopy on grafted samples before and after steam stripping showed no amine leaching and no change in the chemical nature of the amine groups, respectively. Also, a six‐cycle CO2 adsorption/desorption experiment under dry conditions showed no thermal degradation. However, N2 adsorption measurement at 77 K showed significant reductions in the BET surface area of the grafted samples following steaming. Based on the pore size distribution of calcined, grafted samples before and after steaming, it is proposed that exposure to steam restructured the grafted materials, causing mass transfer resistance. It is inferred that triamine‐grafted, large‐pore SBA‐15 adsorbents are potential candidates for CO2 capture at relatively high temperatures (50–75 °C; for example, flue gas) combined with steam regeneration.
The analysis of nitrogen rotational and vibrational bands in a helium microhollow gas discharge
Authors: Majstorović G.Lj. , Jovović J. , Šišović N.M.
Published: August 2017

Emission spectroscopy is applied to measure the gas temperature T
g and the vibrational distribution of N2
(C
3Πu) and N2
+(B
2Σu
+) excited states from a helium microhollow gas discharge (MHGD) at atmospheric pressure. The rotational temperature T
rot of N2
+ is determined from relative intensity of the R‐branch lines of the N2
+(B
2Σu
+–X
2Σg
+) bands at 427.81 and 419.91 nm and the well‐known Boltzmann plot (BP). Using the same diagnostic technique, the rotationally resolved N2(C
3Πu–B
3Πg) band at 380.49 nm is used to measure T
rot. Under our experimental conditions, T
g is equal to T
rot = 550–650 K for nitrogen molecules and shows a slight increase with the discharge current in the current range 3–10 mA. From the intensity ratio of two consecutive vibrational bands of the same sequence, the N2(C
3Πu) and N2
+(B
2Σu
+) vibrational temperature T
vib = 3,700–4,000 K is determined. It has been found that N2
+(B
2Σu
+) ions have non‐Boltzmann distribution in the helium MHGD, while N2(C
3Πu) molecules are populated according to the Boltzmann distribution. Following the Franck–Condon principle, the vibrational distribution of the ground state of N2(X
1Σg
+) molecules has been determined from the N2(C
3Πu) distribution using the inversion matrix of elements q
XC(ν,ν′).
Oral pemphigus vulgaris: Liquid‐based cytological findings and pitfalls
Authors: Kondo Seiji , Kawashima Jiro , Kobata Katsumi , Ohgawara Toshihiro , Tanaka Shiho , Nabeshima Kazuki , Kikuta Toshihiro
Published: August 2017

Pemphigus vulgaris (PV) is a chronic autoimmune bullous disease characterized by the formation of suprabasal cleavage and acantholysis. As this disease almost always affects the oral mucosa, conventional cytological smears of oral lesions can be used for the initial diagnosis of PV. We report two cases of PV that were initially diagnosed based on cytological smears of an oral sample. As atypical squamous cells were present even in the liquid‐based cytological (LBC) smears of the oral lesion in these two cases, this ultimately led to the misinterpretation of squamous cell carcinoma. These findings demonstrate that cytological mimicry of oral PV can occur in malignant cases when there is an absence of appropriate clinical information.
Complexes of {W6I8}4+ Clusters with Carboxylates: Preparation, Electrochemistry, and Luminescence
Authors: Sokolov Maxim N. , Brylev Konstantin A. , Abramov Pavel A. , Gallyamov Marsel R. , Novozhilov Igor N. , Kitamura N. , Mikhaylov Maxim A.
Published: August 2017

The reactions between (Bu4N)2[{W6I8}I6] (1) and silver carboxylates RCOOAg in CH2Cl2 afforded new luminescent carboxylate complexes (Bu4N)2[{W6I8}(RCOO)6] [R = CH3 (2), C6H5 (3), C2F5 (4), C3F7 (5), C6F5 (6)]. The complexes were characterized by single‐crystal X‐ray diffraction, elemental analysis, cyclic voltammetry, and IR and NMR spectroscopy. Complexes 1–6 all exhibit intense and long‐lived photoluminescence. The carboxylate complexes undergo reversible electrochemical oxidation in two consecutive one‐electron steps.
One‐Step Synthesis of 2,5‐Bis(chloromethyl)‐1,4‐dioxane from Epichlorohydrin Using ZIF‐8, Taking Advantage of Structural Defects
Authors: Mousavi Bibimaryam , Luo Zhixiong , Phatanasri Suphot , Su Wei , Wang Tingting , Chaemchuen Somboon , Verpoort Francis
Published: August 2017

We demonstrate herein the ZIF‐8‐only‐mediated catalysis of the cyclodimerization of epichlorohydrin to 2,5‐bis(chloromethyl)‐1,4‐dioxane in the absence of co‐catalyst and solvent. The easy handling and economic aspects of ZIF‐8, in addition to the one‐step reaction to produce the cyclodimer, make this catalyst attractive even for industry. It has been clearly illustrated that the nature of the method used to synthesize ZIF‐8 affected the yields of the cyclodimers. Specifically, the method employed to produce ZIF‐8 directly influences the amount of crystal structural defects, which in turn impacts their performance as catalysts. To emphasize the role of defects, other physical properties, such as surface area and particle size, were controlled during the synthesis of the ZIF‐8 catalysts. Remarkably, the amount of structural defects was quantified by temperature program desorption analysis.
Synthesis and Investigation of Macrocyclic CrIII Bis(alkynyl) Complexes: Structural and Spectroscopic Properties
Authors: Judkins Eileen C. , Tyler Sarah F. , Zeller Matthias , Fanwick Phillip E. , Ren Tong
Published: August 2017

The synthesis and characterization of four new CrIII–bis(alkynyl) complexes bearing the macrocyclic tetraaza ligand DMC (DMC = 5,12‐dimethyl‐1,4,8,11‐tetraazacyclotetradecane) are reported. Complexes trans‐[Cr(DMC)(C2R)2]X (R = Ph ([1]X), Fc ([2]X), X = Cl, ClO4. C2H ([3]X′); X′ = ClO4, BPh4) and cis‐[Cr(DMC)(C4TMS)2]Cl ([4]Cl) were studied using UV/Vis and FTIR spectroscopy, and their identities were verified with ESI‐MS and elemental analysis. The three trans complexes, [1]Cl, [2](ClO4), and [3](BPh4), were structurally characterized using single‐crystal X‐ray diffraction, which revealed a pseudo‐octahedral geometry around the Cr center with the nitrogen atoms occupying the equatorial plane and the alkynyl ligands residing in the apical positions. Spectroscopic analysis of [1]Cl, [3](BPh4) and [4]Cl shows highly structured d–d bands between 320 and 500 nm. All CrIII complexes reported herein are emissive, and detailed studies were performed for [1]Cl, [3](BPh4), and [4]Cl, yielding phosphorescence lifetimes (77 K) of 380, 358, and 160 µs, respectively, and room temperature quantum yields of 0.01 % for complex [1]Cl and 0.15 % for complex [4]Cl. Voltammetric studies of complex [2](ClO4) indicate a weak but discernible coupling between two ferrocenyl groups across the C2–Cr–C2 bridge.
Dialkyl Dicyanofumarates as Oxidizing Reagents for the Conversion of Thiols into Disulfides and Selenols into Diselenides
Authors: Mlostoń Grzegorz , Capperucci Antonella , Tanini Damiano , Hamera‐Fałdyga Róża , Heimgartner Heinz
Published: August 2017

Aliphatic and aromatic thiols react smoothly with dialkyl dicyanofumarates in CH2Cl2 at room temperature to give the corresponding disulfides in excellent yields. Aliphatic 1,2‐, 1,3‐, and 1,4‐dithiols afford cyclic disulfides. Analogous reaction courses were observed for selenols, and the required diselenides also formed in nearly quantitative yields. In all of the reactions, dialkyl dicyanosuccinates formed as 1:1 mixtures of diastereoisomers as the only other product. Cysteamine (2‐mercaptoethylamine) behaved differently; the Michael addition of the primary amine group led to the complete consumption of the dicyanofumarate, and the formation of the disulfide containing an enamine moiety occurred without the formation of dicyanosuccinate.
Is the tier-1 effect assessment for herbicides protective for aquatic algae and vascular plant communities?
Authors: van Wijngaarden René P.A. , Arts Gertie H.P.
Published: August 2017

In the aquatic tier-1 effect assessment for plant protection products with an herbicidal mode of action in Europe, it is usually algae and/or vascular plants that determine the environmental risks. This tier includes tests with at least 2 algae and 1 macrophyte (Lemna). Although such tests are considered to be of a chronic nature (based on the duration of the test in relation to the life cycle of the organism), the measurement endpoints derived from the laboratory tests with plants (including algae) and used in the first-tier effect assessment for herbicides are acute effect concentrations affecting 50% of the test organisms (EC50 values) and not no-observed-effect concentrations (NOECs) or effect concentrations affecting 10% of the test organisms (EC10) values. Other European legislative frameworks (e.g., the Water Framework Directive) use EC10 values. The present study contributes to a validation of the tiered herbicide risk assessment approach by comparing the standard first-tier effect assessment with results of microcosm and mesocosm studies. We evaluated EC50 and EC10 values for standard test algae and macrophytes based on either the growth rate endpoint (ErC50) or the lowest available endpoint for growth rate or biomass/yield (Er/EyC50). These values were compared with the regulatory acceptable concentrations for the threshold option as derived from microcosm and mesocosm studies. For these studies, protection is maintained if growth rate is taken as the regulatory endpoint instead of the lowest value of either growth rate or biomass/yield in conjunction with the standard assessment factor of 10. Based on a limited data set of 14 herbicides, we did not identify a need to change the current practice. Environ Toxicol Chem 2018;37:175–183. © 2017 SETAC
Enantiomer-specific measurements of current-use pesticides in aquatic systems
Authors: Ulrich Elin M. , TenBrook Patti L. , McMillan Larry M. , Wang Qianheng , Lao Wenjian
Published: August 2017

Some current-use pesticides are chiral and have nonsuperimposable mirror images called enantiomers that exhibit identical physical–chemical properties but can behave differently when in contact with other chiral molecules (e.g., regarding degradation and uptake). These differences can result in variations in enantiomer presence in the environment and potentially change the toxicity of pesticide residues. Several current-use chiral pesticides are applied in urban and agricultural areas, with increased potential to enter watersheds and adversely affect aquatic organisms. The present study describes a stereoselective analytical method for the current-use pesticides fipronil, cis-bifenthrin, cis-permethrin, cypermethrin, and cyfluthrin. We show use of the method by characterizing enantiomer fractions in environmental sample extracts (sediment and water), and laboratory-dosed fish and concrete extracts previously collected by California organizations. Enantiomer fractions for most environmental samples are the same as racemic standards (equal amounts of enantiomers, enantiomer fraction = 0.5) and therefore are not expected to differ in toxicity from racemic mixtures typically tested. In laboratory-derived samples, enantiomer fractions are more frequently nonracemic and favor the less toxic enantiomer; permethrin enantiomer fractions range from 0.094 to 0.391 in one type of concrete runoff and enantiomer fractions of bifenthrin in dosed fish range from 0.378 to 0.499. We use enantiomer fractions as a screening tool to understand environmental exposure and explore ways this uncommon measurement could be used to better understand toxicity and risk. Environ Toxicol Chem 2018;37:99–106. Published 2017 Wiley Periodicals Inc. on behalf of SETAC. This article is a US government work and, as such, is in the public domain in the United States of America.

Abstract

Permethrin enantiomer fractions (EFs) measured in water runoff from concrete (red) show differences in applied pesticide formulation. Bifenthrin enantiomer fractions measured in dosed fish over 3 d show a strong nonracemic signature, typical of biological processes.
Radio resource allocation in heterogeneous cellular networks based on effective capacity maximization: Perspective mobile data offloading
Authors: Gholami Mohamad Hassan , Azmi Paeiz , Mokari Nader , Forouzesh Moslem
Published: August 2017

In this paper, a new radio resource allocation approach for mobile data offloading, by means of a local access point (LAP) in the heterogeneous cellular networks is proposed. We consider the uplink path in a single‐carrier frequency‐division multiple access–based multiuser system in a 2‐tier cellular network with a macro base station (BS) and set of LAPs. We assume that there is no internetwork interference between macro BS and LAPs due to the use of 2 different sets of frequencies. Our aim is to allocate resources to determine the best strategy for providing the required quality of service with the criterion of minimum delay in terms of effective capacity maximization. The basis of this work is optimization for the strategy selection. In other words, the selection of the best station and power allocation for offloading in a single‐carrier frequency‐division multiple access multiuser system and solving the problems using the nonlinear optimization with the mesh adaptive direct algorithm solver and the dual decomposition method, respectively. The numerical results validate our analytical outcomes. For example, system delay decreases approximately 10 times if the traffic load of macro BS is decreased by 50%. In addition, we present a comparison of the impact of traffic reduction and consumed bandwidth due to offloading by means of LAPs on the cellular network, which confirms the efficiency of the proposed approach.
Study of the relationship between thermal insulation behavior and microstructure of a fire‐resistant gel containing silica during heating
Authors: Liu Wei , Ge Xinguo , Zhang Zejiang
Published: August 2017

Adding a transparent gel containing silica between 2 sheets of glass could improve the fire resistance of laminated glazing by its thermal intumescent behavior at high temperature. In this study, a custom fire test shows that the glazing reaches the highest thermal insulation rating of 40 minutes when the molar ratio of SiO2 and Na2O in the gel is 4.0, but above this ratio, the thermal insulation rating of the glazing decreases with the increasing silica content. Thermal and scanning electron microscopic analyses have been used to investigate the thermal behavior and microstructure of the residual layer, respectively. The results indicate that, although the high silica content is responsible for the high amount of residue that is essential in the formation of a protection barrier between fire‐exposed and unexposed sides of the glass, it is not the only factor that resulted in the improved thermal insulation of the glazing.
Flexible transparent flame‐retardant membrane based on a novel UV‐curable phosphorus‐containing acrylate
Authors: Wang Xiaomeng , Liu Xueqing , Peng Sha , Peng Panrui , Zou Liyong , Chen Jia , Liu Jiyan
Published: August 2017

A novel phosphorus‐containing acrylate monomer (AOPA) was synthesized starting from 2‐methy‐2,5‐dioxo‐1,2‐oxaphospholane and hydroxyethyl acrylate. The structure of AOPA was characterized with FTIR and 1H NMR. AOPA shows good compatibility with polyethylene glycol diacrylate (PEGDA) and can polymerize with PEGDA under UV light irradiation at different mass ratios to form membranes with high transparency (above 88.9% of light transmittance in the range of 400‐800 nm) and flexibility. Incorporating 20 wt% of AOPA in PEGDA reduced the total heat release and peak rate by 50.3% and 38.4%, respectively, as measured by micro combustion calorimeter. The membrane containing 40 wt% of AOPA with 0.4 mm thickness can pass the UL94 V0 rating, and limiting oxygen index reaches 33.4%. TG‐FTIR and SEM‐EDX analysis show that the presence of AOPA depresses the thermal degradation and promotes the char formation.
Geochronology, geochemistry, and zircon Hf isotopes of the Mo‐bearing granitoids in the eastern Jilin‐Heilongjiang provinces, NE China: Petrogenesis and tectonic implications
Authors: Hou Xue‐Gang , Sun De‐You , Gou Jun , Yang Dong‐Guang
Published: August 2017

In order to investigate their precise geochronological framework, petrogenesis, and tectonic implications, whole‐rock major and trace elements, together with zircon U–Pb and Hf isotope data, are reported for the Mo‐bearing granitoids from the eastern Jilin‐Heilongjiang provinces in the eastern segment of the Central Asian Orogenic Belt. Zircon U–Pb dating by LA–ICP–MS yields crystallization ages for the Liushengdian monzogranite porphyry (252.2 ± 1.6 Ma), the Luming monzogranite porphyry (197.1 ± 1.6 Ma), and the Baoshan granodiorite (164.4 ± 1.9 Ma) and quartz diorite (165.2 ± 1.7 Ma), respectively. This zircon U–Pb data, combined with previous ages, indicate that the eastern Jilin‐Heilongjiang provinces is dominated by 2 stages of ore‐related granitic magmatism and associated Mo mineralization, that is, Late Permian (259–252 Ma) and Early‐Middle Jurassic (200–165 Ma). Geochemically, these Mo‐bearing granitoids have high SiO2 (60.78–74.67 wt.%) and K2O (2.85–6.23 wt.%), low MgO (0.17–2.85 wt.%) and CaO (0.66–4.38 wt.%) contents, with A/NCK and δEu values of 0.87–1.08 and 0.19–1.07, respectively; we infer that they belong to high‐K calc‐alkaline series and are metaluminous to peraluminous in nature. They are characterized by enrichment in large ion lithophile elements and light rare earth elements, and weak depletion in high field strength elements and heavy rare earth elements, consistent with the geochemical signatures of subduction‐related genesis. In addition, in situ Hf isotopic analyses of zircons from 4 dated samples reveal that they have εHf(t) values of −0.4 to +10.3, with 2‐stage model ages varying from 551 to 1,261 Ma, indicating that they probably originated from the partial melting of a dominantly Mesoproterozoic–Neoproterozoic crustal source. On the basis of the geochemical data and regional geological investigations, we propose that the formation of the Late Permian Mo‐bearing granite was related to the subduction of the Paleo‐Asian Ocean plate, whereas the generation of the Early‐Middle Jurassic Mo‐bearing granitoids was associated with the subduction of the Paleo‐Pacific Plate beneath the Eurasian continent.
Quaternary tectonostratigraphic evolution of the Vlora Basin, south‐western Albania
Authors: Palladino Giuseppe , Giannandrea Paolo , Siniscalchi Agata , Magri' Cosimo , Loiacono Francesco
Published: August 2017

The Vlora Bay is a roughly north‐west–south‐east‐oriented tectonic depression located at the collision zone between the Apulian Foreland and the Albano‐Hellenic Chain in south‐western Albania. The bay exhibits a triangular‐shaped geometry, which is the result of different tectonic phases that occurred mostly between the end of the Neogene and the Quaternary. The bay consists of two distinct physiographic sections: a shallow water marine offshore area and a recently emerged onshore sector. Along the onshore sector, Pleistocene clastic sediments filling the Pleistocene Vlora Basin crop out due to the recent uplift phases. The sedimentological and stratigraphic organization of the Vlora Basin deposits and the role played by Quaternary tectonic structures in their deposition are the main topics of this paper. A detailed field survey, supported by a geoelectrical survey, reveals a series of unconformity‐bounded stratigraphic units deposited in two north‐west–south‐east‐oriented subbasins. The two subbasins are separated by an intrabasinal, fault‐bounded, pre‐Quaternary morpho‐structural high and are mainly filled by shallow marine to continental deposits. A detailed structural analysis shows different tectonic phases affecting the area during the Pleistocene. Additionally, the geophysical survey facilitates the reconstruction of the deep structure of the basin and provides a better definition of the basin margins. Based on both geological and geophysical data, a tectonostratigraphic evolutionary model is proposed for the Vlora Basin Pleistocene sedimentary infill. This model consists of three phases of sedimentation that were essentially controlled by fault activity and by the progressive uplift of the area.
IL17A and IL23R gene polymorphisms affect the clinical features and prognosis of patients with multiple myeloma
Authors: Kasamatsu Tetsuhiro , Kimoto Mari , Takahashi Noriyuki , Minato Yusuke , Gotoh Nanami , Takizawa Makiko , Matsumoto Morio , Sawamura Morio , Yokohama Akihiko , Handa Hiroshi , Tsukamoto Norifumi , Saitoh Takayuki , Murakami Hirokazu
Published: August 2017

Single nucleotide polymorphisms (SNPs) in interleukin 17 (IL17A) and IL‐23 receptor (IL23R) are involved in the pathogenesis of many cancers and autoimmune diseases. We investigated the influence of IL17A and IL23R SNPs on the risk of developing multiple myeloma (MM) and its clinical features. We obtained genomic DNA from 120 patients with MM and 201 healthy controls and detected IL17A −197 G/A (rs2275913) and IL23R H3Q (rs1884444) genotypes using the polymerase chain reaction‐restriction fragment length polymorphism method. There were no significant differences in the genotype and allele frequencies of IL17A −197 G/A and IL23R H3Q between the controls and patients with MM. Compared with the GG and GA genotypes, the IL17A AA genotype was significantly associated with lower hemoglobin levels. The IL23R HH genotype was significantly associated with higher frequency of bone lesions and plasmacytoma than the HQ and QQ genotypes. We observed significant differences in overall survival (OS) between patients treated with thalidomide and/or bortezomib and those treated conventionally. Therefore, we also examined the effect of IL17A and IL23R polymorphisms on the clinical variables and OS in patients treated with thalidomide and/or bortezomib. We observed that the IL23R HH genotype was significantly associated with poor survival compared with the QH and HH genotypes in these patients. Our findings indicate that IL17A −197 G/A and IL23R H3Q are not associated with susceptibility to MM. However, IL‐17 and IL‐23R polymorphisms may affect severity, bone lesions, and extra‐medullary disease in patients with MM. Moreover, IL23R polymorphisms may contribute to poor prognosis in patients with MM treated with thalidomide and/or bortezomib.
Does an upper limit to river water temperature apply in all places?
Authors: Shaw Stephen B.
Published: August 2017

There remains continued use of non‐linear, logistic regression models for predicting water temperature from air temperature. A dominant feature of these non‐linear models is an upper bound on river water temperature. This upper bound is often attributed to a large increase in evaporative cooling at high air temperatures, but the exact conditions under which such an increase may occur have not been thoroughly explored. To better understand the appropriateness of the non‐linear model for predicting river water temperatures, it is essential to understand the physical basis for the upper bound and when it should and should not be included in the statistical model. This paper applies and validates an energy balance model against 8 river systems spread across different climate regions of the United States. The energy balance model is then used to develop a diagram relating vapour pressure deficit and air temperature to water temperature. With knowledge of present or future vapour pressure deficit (difference between saturation and actual vapour content in the atmosphere) conditions in a given climate, the diagram can be used to predict the likelihood of an upper bound in the air–water temperature relationship. This investigation offers a fundamental physical explanation of the most appropriate form of statistical models that should be used for predicting future water temperature from air temperature in different geographic regions with different climate conditions. In general, climatic regions that have only a slight increase in vapour pressure deficit with increasing air temperature (typically humid regions) would not be expected to have an upper bound. Conversely, climatic regions in which vapour pressure deficit sharply increases with increasing air temperature (typically arid regions) would be expected to have an upper bound.
Predicting dry‐season flows with a monthly rainfall–runoff model: Performance for gauged and ungauged catchments
Authors: Hamel Perrine , Guswa Andrew J. , Sahl Jake , Zhang Lu
Published: August 2017

Hydrologic models are useful to understand the effects of climate and land‐use changes on dry‐season flows. In practice, there is often a trade‐off between simplicity and accuracy, especially when resources for catchment management are scarce. Here, we evaluated the performance of a monthly rainfall–runoff model (dynamic water balance model, DWBM) for dry‐season flow prediction under climate and land‐use change. Using different methods with decreasing amounts of catchment information to set the four model parameters, we predicted dry‐season flow for 89 Australian catchments and verified model performance with an independent dataset of 641 catchments in the United States. For the Australian catchments, model performance without catchment information (other than climate forcing) was fair; it increased significantly as the information to infer the four model parameters increased. Regressions to infer model parameters from catchment characteristics did not hold for catchments in the United States, meaning that a new calibration effort was needed to increase model performance there. Recognizing the interest in relative change for practical applications, we also examined how DWBM could be used to simulate a change in dry‐season flow following land‐use change. We compared results with and without calibration data and showed that predictions of changes in dry‐season flow were robust with respect to uncertainty in model parameters. Our analyses confirm that climate is a strong driver of dry‐season flow and that parsimonious models such as DWBM have useful management applications: predicting seasonal flow under various climate forcings when calibration data are available and providing estimates of the relative effect of land use on seasonal flow for ungauged catchments.
Sequentially testing polynomial model hypotheses using power transforms of regressors
Authors: Cho Jin Seo , Phillips Peter C. B.
Published: August 2017

We provide a methodology for testing a polynomial model hypothesis by generalizing the approach and results of Baek, Cho, and Phillips (Journal of Econometrics, 2015,187, 376–384; BCP), which test for neglected nonlinearity using power transforms of regressors against arbitrary nonlinearity. We use the BCP quasi‐likelihood ratio test and deal with the new multifold identification problem that arises under the null of the polynomial model. The approach leads to convenient asymptotic theory for inference, has omnibus power against general nonlinear alternatives, and allows estimation of an unknown polynomial degree in a model by way of sequential testing, a technique that is useful in the application of sieve approximations. Simulations show good performance in the sequential test procedure in both identifying and estimating unknown polynomial order. The approach, which can be used empirically to test for misspecification, is applied to a Mincer (Journal of Political Economy, 1958,66, 281–302;Schooling, Experience and Earnings, Columbia University Press, 1974) equation using data from Card (in Christofides, Grant, and Swidinsky (Eds.),Aspects of Labour Market Behaviour: Essays in Honour of John Vanderkamp, University of Toronto Press, 1995, 201‐222) and Bierens and Ginther (Empirical Economics, 2001,26, 307–324). The results confirm that the standard Mincer log earnings equation is readily shown to be misspecified. The applications consider different datasets and examine the impact of nonlinear effects of experience and schooling on earnings, allowing for flexibility in the respective polynomial representations.
Identifying contagion
Authors: Dungey Mardi , Renault Eric
Published: August 2017

Identifying contagion effects during periods of financial crisis is known to be complicated by the changing volatility of asset returns during periods of stress. To untangle this we propose a GARCH (generalized autoregressive conditional heteroskedasticity) common features approach, where systemic risk emerges from a common factor source (or indeed multiple factor sources) with contagion evident through possible changes in the factor loadings relating to the common factor(s). Within a portfolio mimicking factor framework this can be identified using moment conditions. We use this framework to identify contagion in three illustrations involving both single and multiple factor specifications: to the Asian currency markets in 1997–1998, to US sectoral equity indices in 2007–2009 and to the CDS (credit default swap) market during the European sovereign debt crisis of 2010–2013. The results reveal the extent to which contagion effects may be masked by not accounting for the sources of changed volatility apparent in simple measures such as correlation.
Review of the effects of manufactured nanoparticles on mammalian target organs
Authors: Wu Tianshu , Tang Meng
Published: August 2017

Nanotechnology had matured significantly during the last two decades as it has transitioned from bench top science to applied technology. Even though the issue of safety of nanotechnology has been raised nearly one decade ago, the rapid progress in development and use of nanomaterials has not yet been matched by toxicological investigations. Many recent studies have simply outlined the toxic effects of nanoparticles (NPs), but few have systematically addressed their potentially adverse biological effects on target organs. Some animal models have shown that NPs could be accumulated in various organs. These accumulations can access the vasculature and target other organs, resulting in a potential health risks. After the brief description of current knowledge on the wide applications of several common NPs, their applications and the toxicokinetics, this review focused on effects of NPs on organ functions and mammal health after acute or chronic exposure, and potential mechanisms of action. Due to their physical properties, the liver, kidneys and lung are the main target organs of NPs. Most of NPs show slight toxicity when exposed to animals, while certain toxic effects like oxidative stress generation, inflammation and DNA damage are commonly observed. The severity of NPs toxicity is dependent upon several factors, including exposure dose and administration, NPs chemistry, size, shape, agglomeration state, and electromagnetic properties, which could provide useful information necessary to control the toxicity of NPs. Finally, the safety evaluation of nanotoxicity was addressed.