bluuebunny/crossref_metadata_2025 huggingface dataset:
Effect of Potassium and Zinc on Soil Properties and Fraction of Potassium and Zinc in Soil
Authors: Chauhan Ankit H. , Shinde R. D. , Kumar Deelip , Parmar P. M.
Published: September 2024

A field experiment was carried out on Agronomy Farm, B. A. College of Agriculture, Anand Agricultural University, Anand during rabi season of the year 2020-21. The experiment comprising nine treatment combinations consisted of three levels of potassium (0, 20 and 40 kg/ha) and three levels of zinc (0, 2.5 and 5.0 kg/ha). These treatments were evaluated in Randomized Block Design (factorial) with four replications. The soil of the experimental plot was loamy sand in texture, alkaline in reaction, low in organic carbon and available nitrogen, medium in available phosphorus, potassium and zinc. Results of the experiment revealed that the available K2O in soil was significantly increased due to application of 40 kg K2O/ha (K2) and was found to be at par with application of 20 kg K2O/ha (K1). All other chemical properties of soil (pH, EC, organic carbon, available N, P2O5, S, Fe, Mn, Zn and Cu) were not differ significantly due to application of different levels of potassium. Levels of zinc also failed to produce its significant effect on chemical properties of soil except available Zn in soil as it was significantly increased with the treatment of Z2 (5.0 kg Zn/ha) than control but was found to be at par with treatment Z1 (2.5 kg Zn/ha). Moreover, no any chemical property of soil differ due to the interaction of different levels of potassium and zinc. The water soluble K and exchangeable K fractions in soil significantly increased with the treatment of K2 (40 kg K2O/ha) otherwise non-exchangeable K, total K and different zinc fractions in soil did not differ significantly by the different levels of potassium. Different potassium fractions and total Zn fraction in soil were found to be non-significant under the different zinc levels but all the zinc fractions in soil (water soluble plus exchangeable Zn, carbonate bound Zn, Fe/Mn oxide bound Zn, organically bound Zn and residual Zn) significantly increased with the treatment of Z2 (5.0 kg Zn/ha) and was remained at par with treatment Z1 (2.5 kg Zn/ha). The interaction between potassium and zinc failed to influence significantly on potassium and zinc factions in soil.
Comparison of Stool Antigen and PCR-Based Diagnostics for Helicobacter pylori Infection and Associated Gut Dysbiosis in Wad-Medani City, Sudan
Authors: Shashoug Weam S. , Bushra Mohammed , Musa Mohammed B. , Mohamed Nahla , Soud Salma , Nour Bakri Y. M.
Published: September 2024

Background: The development of stomach illnesses has been linked, in part, to Helicobacter pylori (H. pylori) infection; in clinical practice, accurate identification of Helicobacter pylori infection is crucial, H. pylori infection was associated with a decrease in microbial diversity and an increase in pathogenic taxa, indicating its role in gut dysbiosis.
Objectives: We tested a noninvasive method using immunochromatography to detect the presence of the H. pylori antigen in stool specimens. PCR was used to validate the presence of H. pylori by identifying the bacteria's ureC gene in the DNA extracted from stool specimens. Additionally, gut microbiome changes were assessed, understanding the link between H. pylori infection and gut dysbiosis is vital for public health interventions.
Method: A total of 100 stool samples obtained from dyspeptic patients (46 men and 54 women, average age 46.1) were assessed using these methods. The results were then compared between the PCR-based technique and the SAT technique.
Results: The results showed that 35 (35%) out of 100 samples were positive by the PCR-based technique, compared to 33 (33%) positive by the SAT technique and The PCR method demonstrated a sensitivity of 95% and specificity of 92% in detecting H. pylori. Beta diversity was assessed using Bray-Curtis dissimilarity, revealing significant variations in microbial composition among samples.
Conclusion: These data suggest that the techniques used in this study are valuable for studying the molecular epidemiology of H. pylori infection in dyspeptic patients. Stool, as a non-invasive sample, has the potential to be a good replacement for the detection of H. pylori. Additionally, we found that infection with this bacterium contributes to gastric microbial dysbiosis,  while no statistically significant differences were observed.
Investigation on the Hydrothermal Condition in Synthesis of Active Matrix from Metakaolin: Physicochemical Properties and Intrinsic Cracking Activities
Authors: Hudaya Farhansyah Yusuf Putra , Anggaswara Rezky Oktaviandy , Gunawan Melia Laniwati , Kadja Grandprix Thomryes Marth , Makertihartha I. G. B. N.
Published: September 2024

The current trends in research and development of FCC catalyst is focused on the formulation of active matrices that serve as pre-crackers, with the objective of reducing the diffusional resistance of the longer chain hydrocarbon molecule in the feed. In this study, an aluminosilicate active matrix was synthesised from metakaolin using hydrothermal method. The experimental variables that were varied were hydrothermal temperature, in the range of 80 to 110 °C, and hydrothermal time, in the range of 12 to 72 hours, to investigate the best conditions for synthesising the active matrix. Subsequently, the active matrix was subjected to a series of analyses, including X-ray fluorescence, X-ray diffraction, N2 physisorption, NH3-temperature programmed desorption, Fourier transform infrared spectroscopy, scanning electron microscopy and thermogravimetry, with the objective of determining its composition, crystal characteristics, surface characteristics, acidity, functional groups, material structure, and thermal characteristics. Additionally, the active matrix was tested for its intrinsic cracking activity using the micro activity test (MAT). The results indicate that the best temperature for hydrothermal synthesis of the active matrix is 80 °C. The active matrix synthesised with a heating time of 24 hours demonstrated the highest light cycle oil yield, reaching 38.9 wt%. Meanwhile, the active matrix synthesised at 48 hours exhibited the most favourable characteristics, with a specific surface area of 144.23 m2/g and a pore volume of 0.9933 cm3/g, as well as the highest cracking conversion of 70.0 wt%. Copyright © 2024 by Authors, Published by BCREC Publishing Group. This is an open access article under the CC BY-SA License (https://creativecommons.org/licenses/by-sa/4.0).
Oxygen ion response to proton bursty bulk flows
Authors: Nilsson Hans , Hamrin Maria , Pitkänen Timo , Karlsson Tomas , Slapak Rikard , Andersson Laila , Gunell Herbert , Schillings Audrey , Vaivads Andris
Published: July 2016

We have used Cluster spacecraft data from the years 2001 to 2005 to study how oxygen ions respond to bursty bulk flows (BBFs) as identified from proton data. We here define bursty bulk flows as periods of proton perpendicular velocities more than 100 km/s and a peak perpendicular velocity in the structure of more than 200 km/s, observed in a region with plasma beta above 1 in the near‐Earth central tail region. We find that during proton BBFs only a minor increase in the O+ velocity is seen. The different behavior of the two ion species is further shown by statistics of H+ and O+ flow also outside BBFs: For perpendicular earthward velocities of H+ above about 100 km/s, the O+ perpendicular velocity is consistently lower, most commonly being a few tens of kilometers per second earthward. In summary, O+ ions in the plasma sheet experience less acceleration than H+ ions and are not fully frozen in to the magnetic field. Therefore, H+ and O+ motion is decoupled, and O+ ions have a slower earthward motion. This is particularly clear during BBFs. This may add further to the increased relative abundance of O+ ions in the plasma sheet during magnetic storms. The data indicate that O+ is typically less accelerated in association with plasma sheet X lines as compared to H+.
Statistics of auroral hiss and relationship to auroral boundaries and upward current regions
Authors: Spasojevic M.
Published: July 2016

An 8 year database of VLF auroral hiss observations from South Pole station (invariant latitude of −74° with magnetic local time (MLT) = UT −3.5 h) is analyzed. There are three peaks in hiss occurrence as a function of MLT in the evening sector (19–23 MLT), afternoon sector (13–17 MLT), and morning sector (7–11 MLT). The geomagnetic and interplanetary magnetic field (IMF) drivers of hiss are examined in the three MLT sectors, and the results are interpreted using an empirical model of auroral boundaries and an empirical model of field‐aligned current patterns. Auroral hiss on the dayside occurs when the auroral oval is centered near the latitude of the station, and in the afternoon sector higher disturbance levels are required. The afternoon sector favors positive By when Bz is positive and negative By when Bz is strongly negative, while the morning sector favors the complementary conditions. In each case the preference for hiss occurrence follows the pattern of upward field‐aligned currents, and hiss is more likely in the configuration where the peak in the upward current is closer to the latitude of the station. IMF By does not play a role on the nightside where hiss is most likely to occur during moderately weak driving conditions as higher disturbance levels are expected to move the auroral oval and upward current systems to latitudes well equatorward of South Pole.
Multilevel Models
Authors: Goldstein Harvey , Browne William J.
Published: July 2016

Multilevel models, also often known as
random effects
or
mixed models
, are now a well‐established statistical technique with applications in many disciplinary areas, most notably the social and medical sciences. In this article, we provide a basic introduction to these models and discuss extensions that deal with data structures of increasing complexity.
Improved Morphology and Efficiency of Polymer Solar Cells by Processing Donor–Acceptor Copolymer Additives
Authors: Fan Baobing , Sun Chen , Jiang Xiao‐Fang , Zhang Guichuan , Chen Zhiming , Ying Lei , Huang Fei , Cao Yong
Published: July 2016

A novel wide‐bandgap conjugated polymer PBTA‐FPh based on benzodithiophene‐alt‐benzo[1,2,3]triazole as the main chain and a polar pentafluorothiophenyl (FPh) group in the side chain has been designed and synthesized. In comparison to the pristine polymer PBTA‐BO that consists of nonpolar alkyl side chains, the resulting PBTA‐FPh exhibits less pronounced aggregation while possessing analogous optical and electrochemical bandgaps. Contact angle measurements demonstrate that the surface energy can be enhanced by incorporating FPh moiety, leading to a better miscibility of PBTA‐BO with PC71BM in the presence of a certain amount of PBTA‐FPh. The photoactive layer of PBTA‐BO:PC71BM:PBTA‐FPh with weight ratio of 1:1.2:0.02% exhibits a percolated network with the fibrous features, as revealed by transmission electron microscopy measurements. Of particular interest is the significantly improved photovoltaic performances of polymer solar cell devices for which the power conversion efficiency is enhanced from 6.46% for the control device to 7.91% for device processed with PBTA‐FPh as the polymeric additive. These observations indicate that introducing donor–acceptor type of polymeric additive comprising of polar groups in the side chain can be a promising strategy for the fabrication of high‐performance polymer solar cells.
Maternal height and its relationship to offspring birth weight and adiposity in 6‐ to 10‐year‐old Maya children from poor neighborhoods in Merida, Yucatan
Authors: Azcorra Hugo , Dickinson Federico , Datta Banik Sudip
Published: July 2016

Objective

To analyze the relationship between maternal height, offspring birth weight, and adiposity at 6–10 years of age in a sample of 197 mother–child dyads from Merida, Mexico.

Materials and methods

During 2008–2009 and 2011–2013, measurements were taken of maternal height and weight; and height, waist circumference (WC), and skinfolds (triceps, subscapular, and suprailiac) of their children. Participant body composition was estimated using a bioelectrical impedance analyzer. A questionnaire was applied to document household socioeconomic conditions. Multiple linear regression models were used to study the association between maternal height, offspring birth weight and fat mass index (FMI), WC, and sum of skinfolds (SumSkfZ) in boys and girls, separately.

Results

After adjusting for child age and household socioeconomic conditions, maternal height was identified to be significantly associated (p < .05) with FMI, WC, and SumSkf only in boys. In all models, child adiposity was inversely related to maternal height. Offspring birth weight was not associated with any adiposity parameter.

Discussion

The results suggest that maternal nutritional history as reflected in short maternal stature is associated with higher body fat in children, and that male offspring are more vulnerable to intergenerational influences.
Synthesis and Macrodomain Binding of Mono‐ADP‐Ribosylated Peptides
Authors: Kistemaker Hans A. V. , Nardozza Aurelio Pio , Overkleeft Herman S. , van der Marel Gijs A. , Ladurner Andreas G. , Filippov Dmitri V.
Published: July 2016

Mono‐ADP‐ribosylation is a dynamic posttranslational modification (PTM) with important roles in signaling. Mammalian proteins that recognize or hydrolyze mono‐ADP‐ribosylated proteins have been described. We report the synthesis of ADP‐ribosylated peptides from the proteins histone H2B, RhoA and, HNP‐1. An innovative procedure was applied that makes use of pre‐phosphorylated amino acid building blocks. Binding assays revealed that the macrodomains of human MacroD2 and TARG1 exhibit distinct specificities for the different ADP‐ribosylated peptides, thus showing that the sequence surrounding ADP‐ribosylated residues affects the substrate selectivity of macrodomains.
Resin‐supported palladium nanoparticles as recyclable catalyst for the hydrodechlorination of chloroarenes and polychlorinated biphenyls
Authors: Shabbir Saira , Hong Myengchan , Rhee Hakjune
Published: July 2016

This study focuses on the hydrodechlorination of chlorinated arenes as well as polychlorinated biphenyls (PCBs) utilizing a resin‐supported Pd(0) catalyst. Bearing in mind the dangers associated with toxic PCBs, treatment of the remnants of industrial wastes containing PCB congeners is indispensable. One such method is reductive hydrodechlorination. Instead of utilizing traditional sources of hydrogen, ammonium formate is used for in situ hydrogen generation. Moreover, palladium nanoparticles are supported on an anionic exchange resin which makes the process recyclable with a negligible change of yield after recycling experiments. The catalyst is demonstrated in the hydrodechlorination of a wide range of chlorinated compounds and PCB congeners including aroclors 1242, 1248 and 1254. Copyright © 2016 John Wiley & Sons, Ltd.
Ni(II) and Cu(II) complexes with ONNO asymmetric tetradentate Schiff base ligand: synthesis, spectroscopic characterization, theoretical calculations, DNA interaction and antimicrobial studies
Authors: Abdel‐Rahman Laila H. , Abu‐Dief Ahmed M. , Moustafa H. , Hamdan Samar Kamel
Published: July 2016

A novel Schiff base, namely Z‐3‐((2‐((E)‐(2‐hydroxynaphthyl)methylene)amino)‐5‐nitrophenylimino)‐1,3‐dihydroindin‐2‐one, was synthesized from the condensation of 2‐hydroxy‐1‐naphthaldehyde and isatin with 4‐nitro‐o‐phenylenediamine. It was structurally characterized on the basis of 1H NMR, 13C NMR and infrared spectra and elemental analyses. In addition, Ni(II) and Cu(II) complexes of the Schiff base ligand were prepared. The nature of bonding and the stereochemistry of the investigated complexes were elucidated using several techniques, including elemental analysis (C, H, N), Fourier transform infrared and electronic spectroscopies and molar conductivity. The thermal behaviours of the complexes were studied and kinetic–thermodynamic parameters were determined using the Coats–Redfern method. Density functional theory calculations at the B3LYP/6‐311G++ (d, p) level of theory were carried out to explain the equilibrium geometry of the ligand. The optimized geometry parameters of the complexes were evaluated using LANL2DZ basis set. The total energy of highest occupied and lowest unoccupied molecular orbitals, Mullikan atomic charges, dipole moment and orientation are discussed. Moreover, the interaction of the metal complexes with calf thymus DNA (CT‐DNA) was explored using electronic spectra, viscosity measurements and gel electrophoresis. The experimental evidence indicated that the two complexes could strongly bind to CT‐DNA via an intercalation mechanism. The intrinsic binding constants of the investigated Ni(II) and Cu(II) complexes with CT‐DNA were 1.02 × 106 and 2.15 × 106 M−1, respectively, which are higher than that of the standard ethidium bromide. Furthermore, the bio‐efficacy of the ligand and its complexes was examined in vitro against the growth of bacteria and fungi to evaluate the antimicrobial potential. Based on the obtained results, the prepared complexes have promise for use as drugs. Copyright © 2016 John Wiley & Sons, Ltd.
Testing unit roots, structural breaks and linearity in the inflation rates of the G7 countries with fractional dependence techniques
Authors: Gil‐Alana Luis A. , Yaya OlaOluwa S. , Solademi Enitan A.
Published: July 2016

In this paper, we have examined the inflation rates in the Group of Seven countries, investigating issues such as the existence of unit roots, structural breaks, fractional integration and potential non‐linearities using a fractional dependence (FD) approach based on Chebyshev polynomials in time. This robust FD approach allows one to test for persistence as well as non‐linearity of the series. We first tested for stationarity and structural breaks using classical approaches and observed inconclusive results with regard to the stationarity levels of the series. Using Bai–Perron tests, we actually confirmed significant structural breaks, even up to five, in each of the inflation series. However, noting that structural breaks are significantly related to fractional differentiation, this latter approach was also conducted. Here, we observed that the estimates of the differencing parameter were quite stable across time, and evidence of unit roots was found in the cases of the UK, Canada, France, Japan and the USA; for Germany, we found some evidence of mean reversion, while estimates of d above 1 were found in the case of Italy. On the other hand, non‐linear deterministic trends were clearly rejected in all cases. Copyright © 2016 John Wiley & Sons, Ltd.
Quantification of 1‐(propan‐2‐ylamino)‐4‐propoxy‐9H‐thioxanthen‐9‐one (TX5), a newly synthetized P‐glycoprotein inducer/activator, in biological samples: method development and validation
Authors: Ferreira Ana Filipa , Ponte Filipa , Silva Renata , Rocha‐Pereira Carolina , Sousa Emília , Pinto Madalena , Bastos Maria de Lourdes , Remião Fernando
Published: July 2016

A simple, rapid and economical method was developed and validated for the analysis and quantification of 1‐(propan‐2‐ylamino)‐4‐propoxy‐9H‐thioxanthen‐9‐one (TX5), a P‐glycoprotein inducer/activator, in biological samples, using reverse‐phase high‐performance liquid chromatography (HPLC). A C18 column and a mobile phase composed of methanol–water (90/10, v/v) with 1% (v/v) triethylamine, at a flow rate of 1 mL/min, were used for chromatographic separation. TX5 standards (0.5–150 μm) were prepared in human serum. Methanol was used for TX5 extraction and serum protein precipitation. After filtration, samples were injected into the HPLC apparatus and TX5 was quantified by a conventional UV detector at 255 nm. The TX5 retention time was 13 min in this isocratic system. The method was validated according to ICH guidelines for specificity/selectivity, linearity, accuracy, precision, limits of detection and quantification (LOD and LOQ) and recovery. The method was proved to be selective, as there were no interferences of endogenous compounds with the same retention time of TX5. Also, the developed method was linear (r2 ≥ 0.99) for TX5 concentrations between 0.5 and 150 μm and the LOD and LOQ were 0.08 and 0.23 μm, respectively. The results indicated that the reported method could meet the requirements for TX5 analysis in the trace amounts expected to be present in biological samples.
Dominant hemisphere functional networks compensate for structural connectivity loss to preserve phonological retrieval with aging
Authors: Agarwal Smriti , Stamatakis Emmanuel A. , Geva Sharon , Warburton Elizabeth A.
Published: July 2016

Introduction

Loss of hemispheric asymmetry during cognitive tasks has been previously demonstrated in the literature. In the context of language, increased right hemisphere activation is observed with aging. Whether this relates to compensation to preserve cognitive function or dedifferentiation implying loss of hemispheric specificity without functional consequence, remains unclear.

Methods

With a multifaceted approach, integrating structural and functional imaging data during a word retrieval task, in a group of younger and older adults with equivalent cognitive performance, we aimed to establish whether interactions between hemispheres or reorganization of dominant hemisphere networks preserve function. We examined functional and structural connectivity on data from our previously published functional activation study. Functional connectivity was measured using psychophysiological interactions analysis from the left inferior frontal gyrus (LIFG) and the left insula (LINS), based on published literature, and the right inferior frontal gyrus (RIFG) based on our previous study.

Results

Although RIFG showed increased activation, its connectivity decreased with age. Meanwhile, LIFG and LINS connected more bilaterally in the older adults. White matter integrity, measured by fractional anisotropy (FA) from diffusion tensor imaging, decreased significantly in the older group. Importantly, LINS functional connectivity to LIFG correlated inversely with FA.

Conclusions

We demonstrate that left hemispheric language areas show higher functional connectivity in older adults with intact behavioral performance, and thus, may have a role in preserving function. The inverse correlation of functional and structural connectivity with age is in keeping with emerging literature and merits further investigation with tractography studies and in other cognitive domains.
miR‐302b regulates cell cycles by targeting CDK2 via ERK signaling pathway in gastric cancer
Authors: Liu Fu‐Yun , Wang Li‐Ping , Wang Qin , Han Ping , Zhuang Wen‐Ping , Li Mu‐Juan , Yuan Hua
Published: July 2016

To investigate the molecular mechanism of miR‐302b in the regulation of cell proliferation and cell cycle regulation in gastric cancer. Samples of tumor and adjacent normal tissues were collected from 30 gastric cancer patients. Bioinformatics and the dual luciferase report were used for verification of the relationship between miR‐302b expression and cyclin‐dependent kinase 2 (CDK2). RT‐PCR and western blot were used to examine CDK2 mRNA and protein levels. The impacts of miR‐302b on CDK2 expression and extracellular signal‐regulated kinase (ERK) signaling pathway were assessed in cells transfected with miR‐302b analogs and CDK2 overexpression carrier, respectively. We used 3‐(4,5‐dimethylthiazol‐2‐yl)‐2, 5‐diphenyltetrazolium bromide (MTT) to assay gastric cancer cell growth after transfection, flow cytometry to analyze cell cycle. Compared with normal tissues, miR‐302b expression was significantly lower in gastric cancer tissues, which was significantly related to lymph node metastasis, metastasis distance, and TNM staging. miR‐302b expression was increased in miR‐302b mimics transfected cells and was significantly decreased in miR‐302b inhibitors transfected cells. CDK2 is a target gene of miR‐302b. Decreased miR‐302b and increased CDK2 expressions can significantly promote proliferation and G1/S phase transformation in gastric cancer. miR‐302b promoted the proliferation of gastric cancer cells through upregulation of CDK2, thereby inhibiting ERK pathway, which can in turn inhibit the promoting ability of miR‐302b on proliferation. The upregulation of miR‐302b reduced the expression of CDK2, and inhibited ERK signaling pathway, thereby inhibiting cell proliferation and G1/S phase conversion rate. Therefore, miR‐302b provides new perspectives for research of cell regulation and proliferation in gastric cancer, and new targets for gastric cancer diagnosis and treatment.
Angiographic severity does not correlate with fractional flow reserve in heavily calcified coronary arteries
Authors: Johnson Paul M. , Madamanchi Chaitanya , Sharalaya Zarina M. , Iqbal Zahra , Gehi Anil K. , Kaul Prashant , Stouffer George A.
Published: July 2016

Objectives

To determine the relationship between severity of stenosis and hemodynamic significance in calcified coronary arteries.

Background

Severity of stenosis is widely used to determine the need for revascularization but the effect of lesion calcification on hemodynamic significance is not well understood.

Methods

Two hundred consecutive patients undergoing fractional flow reserve (FFR) testing of an intermediate coronary lesion with a pressure wire and intravenous infusion of adenosine were studied. Coronary calcium was quantified based upon radiopacities at the site of the stenosis on cineangiography using the method of Mintz et al. (0 = none or mild calcium, 1 = moderate calcium, 2 = severe calcium).

Results

Mean age was 61 ± 11 years, 66% were males, 87.5% had hypertension, 44.5% had diabetes, and 20.5% were current smokers. The mean coronary stenosis by quantitative coronary angiography was 60 ± 12% and the mean FFR was 0.83 ± 0.08. There were 109, 45, and 46 patients classified as Calcium Score of 0, 1, or 2, respectively. Compared to those with no/mild or moderate calcification, patients with severe coronary calcium were older and more likely to have chronic kidney disease and pulmonary disease. The correlation between angiographic severity and FFR decreased as lesion calcification increased [calcium score = 0 (R2 = 0.25, P < 0.005); calcium score = 1 (R2 = 0.11, P < 0.005); calcium score = 2 (R2 = 0.02, P = 0.35)].

Conclusions

In patients with heavily calcified coronary lesions, there was no association between angiographic stenosis and hemodynamic significance and FFR is needed to determine hemodynamic significance of intermediate lesions. © 2016 Wiley Periodicals, Inc.
Optic nerve astrocytoma in a dog
Authors: Rozov Orr , Piñeyro Pablo E. , Zimmerman Kurt L. , Herring Ian P. , Matusow Rachel , Rossmeisl John H. , Jortner Bernard S. , Dreyfus Jennifer
Published: July 2016

Key Clinical Message

Intracranial astrocytomas are relatively uncommon in dogs and optic nerve astrocytomas even more so. This neoplasm should be considered as differential in canine patients with vision loss, retinal detachment, ocular mass, and histopathologic findings of infiltrative fusiform to polygonal glial cells possibly associated with glomeruloid vascular proliferation.
Catalytic Hydroxylation of Benzene to Phenol by Dioxygen with an NADH Analogue
Authors: Hirose Kensaku , Ohkubo Kei , Fukuzumi Shunichi
Published: July 2016

Hydroxylation of benzene by molecular oxygen (O2) occurs efficiently with 10‐methyl‐9,10‐dihydroacridine (AcrH2) as an NADH analogue in the presence of a catalytic amount of Fe(ClO4)3 or Fe(ClO4)2 with excess trifluoroacetic acid in a solvent mixture of benzene and acetonitrile (1:1 v/v) to produce phenol, 10‐methylacridinium ion and hydrogen peroxide (H2O2) at 298 K. The catalytic oxidation of benzene by O2 with AcrH2 in the presence of a catalytic amount of Fe(ClO4)3 is started by the formation of H2O2 from AcrH2, O2, and H+. Hydroperoxyl radical (HO2.) is produced from H2O2 with the redox pair of Fe3+/Fe2+ by a Fenton type reaction. The rate‐determining step in the initiation is the proton‐coupled electron transfer from Fe2+ to H2O2 to produce HO. and H2O. HO. abstracts hydrogen rapidly from H2O2 to produce HO2. and H2O. The Fe3+ produced was reduced back to Fe2+ by H2O2. HO2. reacts with benzene to produce the radical adduct, which abstracts hydrogen from AcrH2 to give the corresponding hydroperoxide, accompanied by generation of acridinyl radical (AcrH.) to constitute the radical chain reaction. Hydroperoxyl radical (HO2.), which was detected by using the spin trap method with EPR analysis, acts as a chain carrier for the two radical chain pathways: one is the benzene hydroxylation with O2 and the second is oxidation of an NADH analogue with O2 to produce H2O2.
2‐Anilino‐3‐Aroylquinolines as Potent Tubulin Polymerization Inhibitors
Authors: Srikanth P. S. , Nayak V. Lakshma , Suresh Babu Korrapati , Kumar G. Bharath , Ravikumar A. , Kamal Ahmed
Published: July 2016

Several 2‐anilino‐3‐aroylquinolines were designed, synthesized, and screened for their cytotoxic activity against five human cancer cell lines: HeLa, DU‐145, A549, MDA‐MB‐231, and MCF‐7. Their IC50 values ranged from 0.77 to 23.6 μm. Among the series, compounds 7 f [(4‐fluorophenyl)(2‐((4‐fluorophenyl)amino)quinolin‐3‐yl)methanone] and 7 g [(4‐chlorophenyl)(2‐((4‐fluorophenyl)amino)quinolin‐3‐yl)methanone] showed remarkable antiproliferative activity against human lung cancer and prostate cancer cell lines. The IC50 values for inhibiting tubulin polymerization were 2.24 and 2.10 μm for compounds 7 f and 7 g, respectively, and were much lower than that of the reference compound E7010 [N‐(2‐(4‐hydroxyphenylamino)pyridin‐3‐yl)‐4‐methoxybenzenesulfonamide]. Furthermore, flow cytometric analysis revealed that these compounds arrest the cell cycle at the G2/M phase, leading to apoptosis. Apoptosis was also confirmed by mitochondrial membrane potential, Annexin V–FITC assay, and intracellular ROS generation. Immunohistochemistry, western blot, and tubulin polymerization assays showed that these compounds disrupt tubulin polymerization. Molecular docking studies revealed that these compounds bind efficiently to β‐tubulin at the colchicine binding site.
Finite‐time stability of fractional‐order stochastic singular systems with time delay and white noise
Authors: Mathiyalagan Kalidass , Balachandran Krishnan
Published: July 2016

In this article, the finite‐time stochastic stability of fractional‐order singular systems with time delay and white noise is investigated. First the existence and uniqueness of solution for the considered system is derived using the basic fractional calculus theory. Then based on the Gronwall's approach and stochastic analysis technique, the sufficient condition for the finite‐time stability criterion is developed. Finally, a numerical example is presented to verify the obtained theory. © 2016 Wiley Periodicals, Inc. Complexity 21: 370–379, 2016
Homogeneous Catalyzed Reactions of Levulinic Acid: To γ‐Valerolactone and Beyond
Authors: Omoruyi Uwaila , Page Samuel , Hallett Jason , Miller Philip W.
Published: July 2016

Platform chemicals derived from lignocellulosic plant biomass are viewed as a sustainable replacement for crude oil‐based feedstocks. Levulinic acid (LA) is one such biomass‐derived chemical that has been widely studied for further catalytic transformation to γ‐valerolactone (GVL), an important ‘green’ fuel additive, solvent, and fine chemical intermediate. Although the transformation of LA to GVL can be achieved using heterogeneous catalysis, homogeneous catalytic systems that operate under milder reactions, give higher selectivities and can be recycled continuously are attracting considerable attention. A range of new homogeneous catalysts have now been demonstrated to efficiently convert LA to GVL and to transform LA directly to other value‐added chemicals such as 1,4‐pentanediol (1,4‐PDO) and 2‐methyltetrahydrofuran (2‐MTHF). This Minireview covers recent advances in the area of homogeneous catalysis for the conversion of levulinic acid and levulinic ester derivatives to GVL and chemicals beyond GVL.
Fine‐needle aspiration of cervical lymph nodes yields adequate materials for accurate HPV testing in metastatic head and neck squamous cell carcinomas
Authors: Hou Yanjun , Chaudhary Shweta , Shen Rulong , Li Zaibo
Published: July 2016

Background

High‐risk Human papillomavirus (HR‐HPV)‐associated head and neck squamous cell carcinoma (HNSCC) is a distinct epidemiologic and pathologic disease. The data of HR‐HPV testing on fine‐needle aspiration (FNA) materials of cervical lymph nodes in patients with metastatic HNSCC are limited.

Methods

We retrospectively reviewed metastatic HNSCC cases with cervical lymph node FNAs which were tested for p16 immunohistochemistry (IHC) and HR‐HPV DNA in situ hybridization (ISH).

Results

Of the 87 cases studied, the overall adequacy rate of cell block material was 86% for HR‐HPV ISH, 93% for p16 IHC, 84% for both and 95% for either one. Pathologist‐performed FNAs showed significantly higher percentage of satisfactory specimens for p16 and HR‐HPV tests than clinician‐performed FNAs. Of the 73 cases adequate for both p16 IHC and HR‐HPV ISH, the concordant rate between p16 and HR‐HPV results was 78%. P16 positivity had sensitivity of 90% and specificity of 75% to predict primary oropharyngeal HNSCC, while HR‐HPV test showed a similar high sensitivity (91%) but a better specificity (94%).

Conclusion

FNAs of cervical lymph nodes yield adequate materials for reliable HR‐HPV testing in metastatic HNSCCs and should be incorporated into routine pathologic evaluation for these patients. The high concordance between p16 IHC and HR‐HPV ISH suggests p16 IHC may serve as a surrogate for HR‐HPV ISH in metastatic HNSCC cases with oropharyngeal origin and is helpful to pinpoint primary tumor site. Diagn. Cytopathol. 2016;44:792–798. © 2016 Wiley Periodicals, Inc.
Robust calling performance in frogs infected by a deadly fungal pathogen
Authors: Greenspan Sasha E. , Roznik Elizabeth A. , Schwarzkopf Lin , Alford Ross A. , Pike David A.
Published: July 2016

Reproduction is an energetically costly behavior for many organisms, including species with mating systems in which males call to attract females. In these species, calling males can often attract more females by displaying more often, with higher intensity, or at certain frequencies. Male frogs attract females almost exclusively by calling, and we know little about how pathogens, including the globally devastating fungus, Batrachochytrium dendrobatidis, influence calling effort and call traits. A previous study demonstrated that the nightly probability of calling by male treefrogs, Litoria rheocola, is elevated when they are in good body condition and are infected by B. dendrobatidis. This suggests that infections may cause males to increase their present investment in mate attraction to compensate for potential decreases in future reproduction. However, if infection by B. dendrobatidis decreases the attractiveness of their calls, infected males might experience decreased reproductive success despite increases in calling effort. We examined whether calls emitted by L. rheocola infected by B. dendrobatidis differed from those of uninfected individuals in duration, pulse rate, dominant frequency, call rate, or intercall interval, the attributes commonly linked to mate choice. We found no effects of fungal infection status or infection intensity on any call attribute. Our results indicate that infected males produce calls similar in all the qualities we measured to those of uninfected males. It is therefore likely that the calls of infected and uninfected males should be equally attractive to females. The increased nightly probability of calling previously demonstrated for infected males in good condition may therefore lead to greater reproductive success than that of uninfected males. This could reduce the effectiveness of natural selection for resistance to infection, but could increase the effectiveness of selection for infection tolerance, the ability to limit the harm caused by infection, such as reductions in body condition.
Mapping and understanding dry season soil water drawdown by California montane vegetation
Authors: Fellows A. W. , Goulden M. L.
Published: July 2016

The ability of soil to supply plant available water during dry periods is a poorly understood but critically important ecosystem property that affects vegetation health and regional hydrology. We estimated and analyzed the cumulative dry season drawdown of soil water across montane California using a spatially resolved water balance model that combined field, meteorological, and remote sensing observations. Dry season soil water drawdown varied markedly with elevation, increasing from <200 mm/yr below 500 m, to ~425 mm/yr at 1000 to 2000 m, before decreasing to <200 mm/yr above ~3000 m. Soil water drawdown was comparatively low at drier (mean annual precipitation < 1000 mm/yr) or colder (mean annual temperature < 4°C) locations; soil water drawdown was greater at wetter and warmer locations, including conifer forests. The reduced soil water drawdown at low‐elevation dry locations may reflect inadequate precipitation to recharge the soil; the reduced water drawdown at high, cold locations presumably reflects limited storage capacity or sparse vegetation development. Soil water drawdown was reduced at locations that were glaciated during the Pleistocene and was only weakly related to rock type. The amount of soil water drawdown implies that many California ecosystems are deeply rooted, with conifer forest rooting to at least 3.6 m. Deep rooting allows many California ecosystems to limit current summer moisture limitation and suggests some of these ecosystems may be able to also limit future increased moisture stress with climate warming if they are able to support increased evaporative demand by further tapping belowground moisture.
The genetic Allee effect: a unified framework for the genetics and demography of small populations
Authors: Luque Gloria M. , Vayssade Chloé , Facon Benoît , Guillemaud Thomas , Courchamp Franck , Fauvergue Xavier
Published: July 2016

The Allee effect is a theoretical model predicting low growth rates and the possible extinction of small populations. Historically, studies of the Allee effect have focused on demography. As a result, underlying processes other than the direct effect of population density on fitness components are not generally taken into account. There has been heated debate about the potential of genetic processes to drive small populations to extinction, but recent studies have shown that such processes clearly impact small populations over short time scales, and some may generate Allee effects. However, as opposed to the ecological Allee effect, which is underpinned by cooperative interactions between individuals, genetically driven Allee effects require a change in genetic structure to link the decline in population size with a decrease in fitness components. We therefore define the genetic Allee effect as a two‐step process whereby a decrease in population size leads to a change in population genetic structure and, in turn, to a decrease in individual fitness. We describe potential underlying mechanisms and review the evidence for this original type of component Allee effect, using published examples from both plants and animals. The possibility of considering demogenetic feedback in light of genetic Allee effects clarifies the analysis and interpretation of demographic and genetic processes, and the interplay between them, in small populations.
Silica uptake and release in live and decaying biomass in a northern hardwood forest
Authors: Clymans Wim , Conley Daniel J. , Battles John J. , Frings Patrick J. , Koppers Mary Margaret , Likens Gene E. , Johnson Chris E.
Published: July 2016

In terrestrial ecosystems, a large portion (20–80%) of the dissolved Si (DSi) in soil solution has passed through vegetation. While the importance of this “terrestrial Si filter” is generally accepted, few data exist on the pools and fluxes of Si in forest vegetation and the rate of release of Si from decomposing plant tissues. We quantified the pools and fluxes of Si through vegetation and coarse woody debris (CWD) in a northern hardwood forest ecosystem (Watershed 6, W6) at the Hubbard Brook Experimental Forest (HBEF) in New Hampshire,USA. Previous work suggested that the decomposition ofCWDmay have significantly contributed to an excess ofDSi reported in stream‐waters following experimental deforestation of Watershed 2 (W2) at theHBEF. We found that woody biomass (wood + bark) and foliage account for approximately 65% and 31%, respectively, of the total Si in biomass at theHBEF. During the decay of American beech (Fagus grandifolia) boles, Si loss tracked the whole‐bole mass loss, while yellow birch (Betula alleghaniensis) and sugar maple (Acer saccharum) decomposition resulted in a preferential Si retention of up to 30% after 16 yr. A power‐law model for the changes in wood and bark Si concentrations during decomposition, in combination with an exponential model for whole‐bole mass loss, successfully reproduced Si dynamics in decaying boles. Our data suggest that a minimum of 50% of theDSi annually produced in the soil of a biogeochemical reference watershed (W6) derives from biogenic Si (BSi) dissolution. The major source is fresh litter, whereas only ~2% comes from the decay ofCWD. Decay of tree boles could only account for 9% of the excessDSi release observed following the experimental deforestation of W2. Therefore, elevatedDSi concentrations after forest disturbance are largely derived from other sources (e.g., dissolution ofBSi from forest floor soils and/or mineral weathering).
Contacts with large, active individuals intensify the predation risk of small conspecifics
Authors: Yamaguchi Aya , Takatsu Kunio , Kishida Osamu
Published: July 2016

Size variation within a population can influence the structure of ecosystem interactions, because ecological performance differs between individuals of different sizes. Although the impact of size variation in a predator species on the structure of interactions is well understood, our knowledge about how size variation in a prey species might modify the interactions between predators and prey is very limited. Here, by examining the interactions between predatory Hynobius retardatus salamander larvae and their prey, Rana pirica frog tadpoles, we investigated how large prey individuals affect the predation mortality of small prey conspecifics. First, in an experiment conducted in a field pond in which we manipulated the presence of salamanders and large tadpoles (i.e., large enough to protect them against salamander predation) with small tadpoles, we showed that in the presence of large tadpoles the mortality of small tadpoles from salamander predation was increased. On the basis of our observations of the activity of individuals, we hypothesized that active large tadpoles caused physical disturbances, which in turn caused the small tadpoles to move, and thus increased their encounter frequency with the predatory salamanders. To test this hypothesis, we conducted a laboratory experiment in small tanks with three players (i.e., one salamander as predator, one small tadpole as focal prey, and either a small or a large tadpole as the prospective movement inducer). In each tank, we manipulated the presence or absence of a movement inducer, and, when present, its size (large or small) and access (caged or uncaged) to the focal prey. In the presence of a large, uncaged movement inducer, the focal prey was more active and suffered from higher predation mortality compared with the other treatments, because the large movement inducer (unlike a small movement inducer) moved actively and, when uncaged, could stimulate movement of the focal prey through direct contact. The results indicated that high activity of large prey individuals and the resulting behavioral interactions with small conspecifics via direct contact indirectly increased the mortality of the small prey.
Current multiple sclerosis treatments have improved our understanding of MS autoimmune pathogenesis
Authors: Martin Roland , Sospedra Mireia , Rosito Maria , Engelhardt Britta
Published: July 2016

Multiple sclerosis (MS) is the most common inflammatory disorder of the central nervous system (CNS) in young adults. When MS is not treated, it leads to irreversible and severe disability. The etiology of MS and its pathogenesis are not fully understood. The recent discovery that MS‐associated genetic variants code for molecules related to the function of specific immune cell subsets is consistent with the concept of MS as a prototypic, T‐cell‐mediated autoimmune disease targeting the CNS. While the therapeutic efficacy of the currently available immunomodulatory therapies further strengthen this concept, differences observed in responses to MS treatment as well as additional clinical and imaging observations have also shown that the autoimmune pathogenesis underlying MS is much more complex than previously thought. There is therefore an unmet need for continued detailed phenotypic and functional analysis of disease‐relevant adaptive immune cells and tissues directly derived from MS patients to unravel the immune etiology of MS in its entire complexity. In this review, we will discuss the currently available MS treatment options and approved drugs, including how they have contributed to the understanding of the immune pathology of this autoimmune disease.
Nano‐Nonanuclear Mixed‐Lanthanide Clusters [Eu9–xTbx] Featuring Tunable Dual Luminescence Properties
Authors: Guettas Djamila , Balogh Cristina M. , Sonneville Camille , Malicet Ylane , Lepoivre Florian , Onal Emel , Fateeva Alexandra , Reber Christian , Luneau Dominique , Maury Olivier , Pilet Guillaume
Published: July 2016

Five Tb3+/Eu3+ mixed nonanuclear clusters with the general formula [Eu9–xTbx(acac)16(µ3‐OH)8(µ4‐O)(µ4‐OH)] ([Eu9–xTbx], x = 0.9–8.1, acac = acetylacetonate) were synthesized. Characterization by powder X‐ray diffraction (PXRD), energy‐dispersive X‐ray spectroscopy (EDS) and inductively coupled plasma optical emission spectroscopy (ICP‐OES) highlight a near‐perfect match between the amounts of Tb3+ and Eu3+ ions input in the reaction mixture and the amounts in the clusters. The luminescence properties of these [Eu9–xTbx] clusters were investigated thoroughly in the solid state, and a strong energy transfer from the Tb3+ to Eu3+ emitters was evidenced. Thus, these nano‐nonanuclear 4f clusters, which can be viewed as square pyramids that share one top, exhibit dual luminescence that can be adjusted by controlling the ratio of the lanthanide ions within the crystal architecture.