bluuebunny/crossref_metadata_2025 huggingface dataset:
Combined effects of local habitat, anthropogenic stress, and dispersal on stream ecosystems: a mesocosm experiment
Authors: Turunen Jarno , Louhi Pauliina , Mykrä Heikki , Aroviita Jukka , Putkonen Emmi , Huusko Ari , Muotka Timo
Published: June 2018

The effects of anthropogenic stressors on community structure and ecosystem functioning can be strongly influenced by local habitat structure and dispersal from source communities. Catchment land uses increase the input of fine sediments into stream channels, clogging the interstitial spaces of benthic habitats. Aquatic macrophytes enhance habitat heterogeneity and mediate important ecosystem functions, being thus a key component of habitat structure in many streams. Therefore, the recovery of macrophytes following in‐stream habitat modification may be prerequisite for successful stream restoration. Restoration success is also affected by dispersal of organisms from the source community, with potentially the strongest responses in relatively isolated headwater sites that receive a limited amount of dispersing individuals. We used a factorial design in a set of stream mesocosms to study the independent and combined effects of an anthropogenic stressor (sand sedimentation), local habitat (macrophytes, i.e., moss transplants), and enhanced dispersal (two levels: high vs. low) on organic matter retention, algal accrual rate, leaf decomposition, and macroinvertebrate community structure. Overall, all responses were simple additive effects with no interactions between treatments. Sand reduced algal accumulation, total invertebrate density, and density of a few individual taxa. Mosses reduced algal accrual rate and algae‐grazing invertebrates, but enhanced organic matter retention and the number of detritus and filter feeders. Mosses also reduced macroinvertebrate diversity by increasing the dominance by a few taxa. Mosses reduced leaf mass loss, possibly because the organic matter retained by mosses provided an additional food source for leaf‐shredding invertebrates and thus reduced shredder aggregation into leaf packs. The effect of mosses on macroinvertebrate communities and ecosystem functioning was distinct irrespective of the level of dispersal, suggesting strong environmental control of community structure. The strong environmental control of macroinvertebrate community composition even under enhanced dispersal suggests that re‐establishing key habitat features, such as natural stream vegetation, could aid ecosystem recovery in boreal streams.
Half‐Sandwich Metal Complexes with β‐Diketone‐Like Ligands and Their Anticancer Activity
Authors: Pettinari Riccardo , Marchetti Fabio , Di Nicola Corrado , Pettinari Claudio
Published: June 2018

Half‐sandwich organometal complexes of RuII, OsII, RhIII and IrIII with β‐diketone‐like ligands have been extensively explored as potential prodrugs in anticancer therapy in recent years. Here a minireview of this class of compounds is provided. A discussion of the basic structural features of the metal complexes is given, together with their in vitro anticancer activity.
Quantification of Phorbol Esters in Jatropha curcas by HPLC‐UV and HPLC‐ToF‐MS with Standard Addition Method
Authors: Neu Philipp M. , Schober Sigurd , Mittelbach Martin
Published: June 2018

Established analytic methods for the quantification of phorbol esters (PE), which are some toxic components in Jatropha curcas L., include HPLC with UV‐detection with the commercially available phorbol myristate acetate (PMA) as internal standard or HPLC coupled with MS detection with an external calibration, mostly also with PMA. The differences in the fatty acid side chains and connection to the base structure of PMA compared to PE leads to different UV absorption and MS ionization effects and cause problems for exact quantitative measurements. In this paper, a method is presented which combines both detection types and shows differences between both results. For this purpose, an extraction routine is performed on a PE‐containing seed oil to get a PE standard in high purity, which was used for a standard addition method on two real J. curcas oil samples, derived from Ghana and Mexico. Furthermore, a detection window of ±10 ppm for the high accurate ToF‐MS detection is set to eliminate isobaric interferences from co‐eluting material. Method evaluation of inter‐ and intra‐day variance as well as the recovery rate are performed and determined. With this method a limit of detection of 62 ng mL−1 (UV) and 11 ng mL−1 (MS) can be achieved.

Practical Applications: Due to the good biological and technical properties of Jatropha curcas L., its seed oil seems perfect for the application as biodiesel feedstock. The toxicity on the other hand could cause problems when converting side products from the oil production to products of higher value. With the here described method an accurate and precise analysis procedure for the quantification of the toxic compounds namely, phorbol esters, could be applied for toxicity studies or routine checks in industry which is converting plant material from J. curcas, so that no toxic material is used for example as animal feed.

In this paper, an exact and robust analysis method is described for the quantification of phorbol esters (PE) in Jatropha curcas L. seed oil. This method procedure includes the extraction of PE in methanol, chromatographic separation on a reverse phase C18 HPLC column and the quantification by standard addition method. For the standard addition method a highly pure PE standard is used, which is extracted and purified by semi preparative HPLC right before the measurements. The used detector for identification and quantification is UV set at 280 nm and ESI‐ToF‐MS with a ±10 ppm mass difference of the deprotonated and formate adduct pseudo molecular ion of PE.
Identification of Phytyl Vaccinate as a Major Component of Wax Ester Fraction of Extra Virgin Olive Oil
Authors: Mariani Carlo , Lucci Paolo , Conte Lanfranco
Published: June 2018

Despite the great efforts devoted to the study of the chemical composition of olive oil, the identification of minor components is still incomplete. Within this context, the characterization of esters of fatty alcohols with fatty acids is far from complete. The objective of this study is to investigate phytyl wax esters profile of extra‐virgin olive oils, in order to provide an update on the current knowledge of the chemical composition of this fraction. Extra‐virgin olive oil waxes are transesterificated with HCl/isobutanol and isobutyl esters are analyzed by GC‐FID and GC‐MS using two capillary columns with different polarity. A comparison of the GC retention times with analytical standards together with the acquired mass spectra allow to identify and confirm, for the first time, phytyl vaccinate as the relevant unknown peak detected in the wax esters fraction of extra‐virgin olive oils. Additionally, the analysis of the composition of aliphatic alcohols obtained by hydrolysis of waxes reveals that the preponderant compound is C24 alcohol derived from lignoceryl palmitate, which is practically the only wax really present, while the low level of C28 alcohol confirms that extra‐virgin olive oils of good quality contain negligible amounts of long‐chain waxes which are derived from C28 alcohol.

Practical Applications: Phytil vaccinate has been shown for the first time as a relevant component of apolar olive oil fraction, highlighting the importance of studying the biosynthesis of the esterified apolar fraction of extra virgin olive oils since acids esterified with diterpenes are quantitatively different from those found in triglycerides. From a nutritional point of view, the identification and characterization of the diterpenic esters profiles of the apolar fraction of extra virgin olive oils is of particular interest, especially considering that these compounds contribute to the reduction of blood cholesterol levels.

This study has demonstrates, for the first time, the presence of phytyl vaccinate as a relevant component of apolar olive oil fraction.
An Intramolecular C(sp2)–H Amidation Using N‐Iodosuccinimide
Authors: Alam Md Toufique , Maiti Saikat , Mal Prasenjit
Published: June 2018

An N‐iodosuccinimide (NIS) mediated intramolecular dehydrogenative C(sp2)–H amidation is reported for easy and convenient access to 1,2‐disubstituted benzimidazoles. The nonprefunctionalized C(sp2)–H and N(sp3)–H bonds were directly coupled using NIS in trifluoroethanol, which proved to be mild alternative to strong oxidative iodine(III) reagents. The reaction worked at room temperature, under an air atmosphere, and in the absence of any base additive.
Reaction of 1,2‐Anhydrosugars with Arynes: An Approach to 1,2‐Dihydrobenzofuran‐Fused C‐Aryl Glycosides and C2‐O‐Phenolic Glycals
Authors: Dubbu Sateesh , Vankar Yashwant D.
Published: June 2018

A one‐step method for the synthesis of 1,2‐dihydrobenzofuran‐fused C‐aryl glycosides and C2‐O‐phenolic glycals from the reaction of 1,2‐anhydrosugars with in situ generated arynes has been developed. The glucal‐ and galactal‐derived 1,2‐anhydrosugars smoothly underwent the reaction to give the products in good yields. The C2‐O‐phenolic glycals could serve as new synthons in carbohydrate chemistry.
Game theoretic frequency reuse approach in OFDMA femtocell networks
Authors: Ghosh Joydev , Jayakody Dushantha Nalin K.
Published: June 2018

In this paper, we initially dealt with the issue of spectrum allocation among macro (or “licensed”) and femto (or “unlicensed”) users in an orthogonal frequency division multiple access femtocell network of noncooperative game theoretic frequency reuse approach. We formulate the difficulty based on spectrum bidding. Here, individual secondary users (SUs) create an auction for the amount of bandwidth and every primary user can share the frequency band among SUs by itself according to the intelligence from SUs without lowering its own performance. Here, we consider that the bidding is a noncooperative game and one of its solutions is a Nash equilibrium. The femto base stations are grouped into different cluster for mitigating the undesired interference among them. The game theoretical method deals with the intercluster frequency clashes. We exemplified a link between utility function and the number of players by noncooperative game theoretic approach to guide the spectrum sharing decision at the cell edges. The convergence of the development mechanism is rigorously scrutinized and extensive numerical outcomes are presented to illustrate their potential merits.
Patatin‐like phospholipase domain containing 3 variants differentially impact metabolic traits in individuals at high risk for cardiovascular events
Authors: Rüschenbaum Sabrina , Schwarzkopf Katharina , Friedrich‐Rust Mireen , Seeger Florian , Schoelzel Fabian , Martinez Yolanda , Zeuzem Stefan , Bojunga Jörg , Lange Christian M.
Published: June 2018

Single nucleotide polymorphism (SNP) rs738409 C>G in the patatin‐like phospholipase domain containing 3 (PNPLA3) gene results in an amino acid exchange from isoleucin to methionine at position I148M of PNPLA3. The expression of this loss‐of‐function mutation leads to impaired hepatocellular triglyceride hydrolysis and is associated with the development of liver steatosis, fibrosis, and hepatocellular carcinoma. In contrast to these well‐established associations, the relationship of the PNPLA3 rs738409 variant with other metabolic traits is incompletely understood. We therefore assessed the association of the PNPLA3 rs738409 genotype with relevant metabolic traits in a prospective study of patients at high risk for cardiovascular events, i.e., patients undergoing coronary angiography. In a total of 270 patients, known associations of the PNPLA3 rs738409 GG genotype with nonalcoholic steatohepatitis and liver fibrosis were confirmed. In addition, we found an association of the PNPLA3 rs738409 G allele with the presence of diabetes (22% versus 28% versus 58% for CC versus CG versus GG genotype, respectively; P = 0.02). In contrast to its association with nonalcoholic fatty liver disease, liver fibrosis, and diabetes, the minor G allele of PNPLA3 rs738409 was inversely associated with total serum cholesterol and low‐density lipoprotein serum levels (P = 0.003 and P = 0.02, respectively). Finally, there was a trend toward an inverse association between the presence of the PNPLA3 rs738409 G allele and significant coronary heart disease. Comparable trends were observed for the transmembrane 6 superfamily member 2 (TM6SF2) 167 K variant, but the sample size was too small to evaluate this rarer variant. Conclusion: The PNPLA3 rs738409 G allele is associated with liver disease but also with a relatively benign cardiovascular risk profile. (Hepatology Communications 2018;2:798‐806)
Anatomical subsite can modify the association between meat and meat compounds and risk of colorectal adenocarcinoma: Findings from three large US cohorts
Authors: Etemadi Arash , Abnet Christian C. , Graubard Barry I. , Beane‐Freeman Laura , Freedman Neal D. , Liao Linda , Dawsey Sanford M. , Sinha Rashmi
Published: June 2018

Distal and proximal colon tumors have distinct incidence trends and embryonic origins; whether these sub‐sites have distinct susceptibilities to known risk factors is unclear. We used pooled data from 407,270 participants in three US‐based studies, with overall median follow‐up of 13.8 years. We used adjusted Cox models to analyze the association between dietary intakes (from diet history questionnaire) of total, processed and unprocessed red meat; total white meat, poultry and fish and meat‐related compounds: heme iron, nitrate, nitrite, the heterocyclic amines (HCAs) and benzo(a)pyrene (B(a)P) and incidence of colorectal cancer subsites. The risk of colorectal cancer (n = 6,640) increased by 35% for each 50 g/1,000 kcal higher daily intake of total red meat, with a significant right‐to‐left trend from proximal colon (HR: 1.24; 95% CI: 1.09–1.39) to distal colon (HR: 1.34; 95% CI: 1.13–1.55) and rectum (HR: 1.53; 95% CI: 1.28–1.79). Only unprocessed red meat showed a significant right‐to‐left trend. Each 50 g/1,000 kcal increase in white meat intake was associated with a 26% reduction in total colorectal cancer risk (HR: 0.74; 95% CI: 0.68–0.80), with a significant inverse right‐to‐left trend. The highest quintile of heme iron was associated with increased cancer risk only in the distal colon (HR: 1.20; 95% CI: 1.02–1.42) and rectum (HR: 1.27; 95% CI: 1.07–1.52). The highest quintile of HCAs, and nitrate/nitrite were associated with increased risk of total colorectal cancer, but these associations did not vary across anatomical subsites. In summary, right and left subsites of the colon may have distinct susceptibilities to meat and possibly other dietary risk factors, suggesting that the causes of colorectal cancer may vary across anatomical subsites.
Low tumor infiltrating mast cell density confers prognostic benefit and reflects immunoactivation in colorectal cancer
Authors: Mao Yihao , Feng Qingyang , Zheng Peng , Yang Liangliang , Zhu Dexiang , Chang Wenju , Ji Meiling , He Guodong , Xu Jianmin
Published: June 2018

The role of mast cells (MCs) in colorectal cancer (CRC) progression was controversial. Thus, our study was designed to evaluate the prognostic value of MCs as well as their correlation with immune microenvironment. A retrospective cohort of CRC patients of stages I–IV was enrolled in our study. Consecutive patients (854) were divided into training set (427 patients) and validation set (427 patients) randomly. The findings were further validated in a GEO cohort, GSE39582 (556 patients). The mast cell density (MCD) was measured by immunohistochemical staining of tryptase or by CIBERSORT algorithm. Low MCD predicted prolonged overall survival (OS) in training and validation set. Moreover, MCD was identified as an independent prognostic indicator in both sets. Better stratification for CRC prognosis can be achieved by building a MCD based nomogram. The prognostic role of MCD was further validated in GSE39582. In addition, MCD predicted improved survival in stages II and III CRC patients receiving adjuvant chemotherapy (ACT). Multiple immune pathways were enriched in low MCD group while cytokines/chemokines promoting anti‐tumor immunity were highly expressed in such group. Furthermore, MCD was negatively correlated with CD8+ T cells infiltration. In conclusion, MCD was identified as an independent prognostic factor, as well as a potential biomarker for ACT benefit in stages II and III CRC. Better stratification of CRC prognosis could be achieved by building a MCD based nomogram. Moreover, immunoactivation in low MCD tumors may contributed to improved prognosis.
Dynamic factor model with infinite‐dimensional factor space: Forecasting
Authors: Forni Mario , Giovannelli Alessandro , Lippi Marco , Soccorsi Stefano
Published: June 2018

The paper compares the pseudo real‐time forecasting performance of three dynamic factor models: (i) the standard principal component model introduced by Stock and Watson in 2002; (ii) the model based on generalized principal components, introduced by Forni, Hallin, Lippi, and Reichlin in 2005; (iii) the model recently proposed by Forni, Hallin, Lippi, and Zaffaroni in 2015. We employ a large monthly dataset of macroeconomic and financial time series for the US economy, which includes the Great Moderation, the Great Recession and the subsequent recovery (an update of the so‐called Stock and Watson dataset). Using a rolling window for estimation and prediction, we find that model (iii) significantly outperforms models (i) and (ii) in the Great Moderation period for both industrial production and inflation, and that model (iii) is also the best method for inflation over the full sample. However, model (iii) is outperformed by models (ii) and (i) over the full sample for industrial production.
Hearing and quality of life in older adults
Authors: Hyams Adriana V. , Hay‐McCutcheon Marcia , Scogin Forrest
Published: June 2018

Objectives

We assessed quality of life (QoL) in older adults with and without hearing loss (HL) and studied how hearing aids were associated with QoL. We hypothesized participants with normal hearing would have significantly better QoL than participants with HL and hearing aids, and participants with HL but no aids would have the worst QoL.

Method

At the University of Alabama and rural public health departments in surrounding counties, we tested 100 males and females aged 60–87 using pure‐tone audiometry. They completed Short Form‐36 and Medical Outcome Study assessments. We analyzed data with MANCOVA (covariate income).

Results

Participants without hearing aids had significantly poorer QoL than participants with normal hearing, who did not significantly differ from participants with aids. General health drove the difference.

Conclusions

Hearing aids are associated with better QoL than having HL and going without aids. Clinical psychologists can improve coping among those with HL and motivate hearing aid use.
Population Pharmacokinetic Modeling With Enterohepatic Circulation for AZD3241 in Healthy Subjects and Patients With Multiple System Atrophy
Authors: Tong Xiao , Zhou Diansong , Savage Alicia , Mullen Jamie A. , Li Yan , Taylor Wendy , Li Jianguo , Al‐Huniti Nidal , Xu Hongmei
Published: June 2018

AZD3241 is a potent and selective myeloperoxidase inhibitor potentially for the treatment of a number of neurodegenerative disorders, including multiple system atrophy (MSA). The objectives of this work were to develop a population pharmacokinetic (PopPK) model for AZD3241 and to investigate the correlation between AZD3241 exposure and myeloperoxidase inhibition. The PopPK model was developed using AZD3241 data from one phase 1 study in healthy subjects and one phase 2 study in patients with MSA. A one‐compartment model incorporating a gallbladder compartment for enterohepatic circulation, sequential zero‐first order absorption, and first‐order elimination adequately described the AZD3241 concentration profiles. The apparent clearance and central volume of distribution were 63.1 L/h (interindividual variability: 34.8%) and 121.9 L (interindividual variability: 44.0%), respectively. The enterohepatic circulation model reasonably captured the second peak of AZD3241, and high‐fat food increased the absorption rate by 69%. A linear regression model was applied to describe the relationship between AZD3241 exposure and percentage change from baseline in myeloperoxidase‐specific activity. The developed PopPK model was consistent with known pharmacokinetic characteristics of AZD3241. This model can be used to estimate AZD3241 exposure in patients with MSA and could be applied to future pharmacokinetic‐pharmacodynamic analyses of AZD3241 in clinical development.
Is obesity rather than the dietary supplement used for weight reduction the cause of liver injury?
Authors: Teschke Rolf , Wolff Albrecht , Eickhoff Axel , Danan Gaby
Published: June 2018

Acute liver injury has been attributed to dietary supplements (DS) used for weight loss, but their causal role was much questioned, and obesity as an alternative cause of the liver injury remained unclear. A comprehensive search of the Medline database was conducted with terms that included “DS,” “liver injury,” “obesity,” “obesity‐related liver diseases,” and “nonalcoholic steatohepatitis.” For each term, we focused on the first 50 publications. We undertook a manual search to identify additional reports. Underlying liver diseases and other health issues are common in patients taking DS for weight reduction. These include obesity or morbid obesity, as well as complex metabolic disorders complicated by excess morbidity and mortality due to associated liver diseases. Among these are nonalcoholic fatty liver disease with potential progression to nonalcoholic steatohepatitis and cirrhosis, often classified as cryptogenic with a rare risk of hepatocellular carcinoma. With the exception of hepatocellular carcinoma, these obesity‐related liver diseases were observed to varying degrees in patients, and some even required a liver transplant. This raises the question whether the liver injury that occurred in these patients is due to DS consumed for weight loss or to the underlying obesity‐related liver diseases. This analysis showed that, in many instances, the causal role of obesity has been neglected. Obesity‐associated liver diseases should be considered as differential diagnosis of liver injury in obese patients using DS.
Synthesis and Anti‐inflammatory Activity of Some New 1,2,3‐Benzotriazine Derivatives Using 2‐(4‐Oxo‐6‐phenylbenzo[d][1,2,3]triazin‐3(4H)‐yl)acetohydrazide as a Starting Material
Authors: Selim Yasser A. , Abd El‐Azim Mohamed H. M. , El‐Farargy Ahmed F.
Published: June 2018

In continuation to our search for new heterocyclic system‐based anti‐inflammatory activity, a series of novel 1,2,3‐benzotriazine derivatives were synthesized. The pharmacological screening showed that many of these compounds have good anti‐inflammatory activity. The structure assignments of the new synthesized compounds are based on spectroscopic data, and pharmacological properties are reported.
Regioselective Synthesis of Polyfluoroalkyl Substituted 6,7‐Dihydrobenzisoxazolones
Authors: Khlebnicova Tatyana S. , Piven' Yurii A. , Isakova Veronica G. , Baranovsky Alexander V. , Lakhvich Fedor A. , Sorochinsky Alexander E. , Gerus Igor I.
Published: June 2018

Regioselective methods for synthesis of hitherto unreported both 6,7‐dihydro‐1,2‐benzisoxazol‐4(5H)‐ones and 6,7‐dihydro‐2,1‐benzisoxazol‐4(5H)‐ones with perfluoroalkyl or halogenodifluoromethyl substituents have been developed. 3‐Polyfluoroalkyl‐6,7‐dihydro‐1,2‐benzisoxazol‐4(5H)‐ones were prepared by the cyclocondensation of 2‐polyfluoroalkanoylcyclohexane‐1,3‐diones with hydroxylamine. The regioisomeric 3‐polyfluoroalkyl‐6,7‐dihydro‐2,1‐benzisoxazol‐4(5H)‐ones were synthesized by the transformation of 2‐polyfluoroalkanoylcyclohexane‐1,3‐diones into their vinylogous chlorides, followed by the interaction of obtained crude 3‐chloro‐2‐polyfluoroalkanoyl‐2‐cyclohexen‐1‐ones with sodium azide in dimethylformamide.
Evidence of synergistic relationships between HIV and Human Papillomavirus (HPV): systematic reviews and meta‐analyses of longitudinal studies of HPV acquisition and clearance by HIV status, and of HIV acquisition by HPV status
Authors: Looker Katharine J , Rönn Minttu M , Brock Patrick M , Brisson Marc , Drolet Melanie , Mayaud Philippe , Boily Marie‐Claude
Published: June 2018

Introduction

Observational studies suggest HIV and human papillomavirus (HPV) infections may have multiple interactions. We reviewed the strength of the evidence for the influence of HIV on HPV acquisition and clearance, and the influence of HPV on HIV acquisition.

Methods

We performed meta‐analytic systematic reviews of longitudinal studies of HPV incidence and clearance rate by HIV status (review 1) and of HIV incidence by HPV status (review 2). We pooled relative risk (RR) estimates across studies using random‐effect models. I2 statistics and subgroup analyses were used to quantify heterogeneity across estimates and explore the influence of participant and study characteristics including study quality. Publication bias was examined quantitatively with funnel plots and subgroup analysis, as well as qualitatively.

Results and Discussion

In review 1, 37 publications (25 independent studies) were included in the meta‐analysis. HPV incidence (pooled RR = 1.55, 95% CI: 1.29 to 1.88; heterosexual males: pooled RR = 1.95, 95% CI: 1.62, 2.34; females: pooled RR = 1.63, 95% CI: 1.26 to 2.11; men who have sex with men: pooled RR = 1.36, 95% CI: 1.01 to 1.82) and high‐risk HPV incidence (pooled RR = 2.20, 95% CI: 1.90 to 2.54) was approximately doubled among people living with HIV (PLHIV) whereas HPV clearance rate (pooled RR = 0.53, 95% CI: 0.42 to 0.67) was approximately halved. In review 2, 14 publications (11 independent studies) were included in the meta‐analysis. HIV incidence was almost doubled (pooled RR = 1.91, 95% CI 1.38 to 2.65) in the presence of prevalent HPV infection. There was more evidence of publication bias in review 2, and somewhat greater risk of confounding in studies included in review 1. There was some evidence that adjustment for key confounders strengthened the associations for review 2. Misclassification bias by HIV/HPV exposure status could also have biased estimates toward the null.

Conclusions

These results provide evidence for synergistic HIV and HPV interactions of clinical and public health relevance. HPV vaccination may directly benefit PLHIV, and help control both HPV and HIV at the population level in high prevalence settings. Our estimates of association are useful for mathematical modelling. Although observational studies can never perfectly control for residual confounding, the evidence presented here lends further support for the presence of biological interactions between HIV and HPV that have a strong plausibility.
Decoding the chemotactic signal
Authors: Thomas Monica A , Kleist Andrew B , Volkman Brian F
Published: June 2018

From an individual bacterium to the cells that compose the human immune system, cellular chemotaxis plays a fundamental role in allowing cells to navigate, interpret, and respond to their environments. While many features of cellular chemotaxis are shared among systems as diverse as bacteria and human immune cells, the machinery that guides the migration of these model organisms varies widely. In this article, we review current literature on the diversity of chemoattractant ligands, the cell surface receptors that detect and process chemotactic gradients, and the link between signal recognition and the regulation of cellular machinery that allow for efficient directed cellular movement. These facets of cellular chemotaxis are compared among E. coli, Dictyostelium discoideum, and mammalian neutrophils to derive organizational principles by which diverse cell systems sense and respond to chemotactic gradients to initiate cellular migration.

We review the signal recognition process in mammalian neutrophils in order to derive general principles by which diverse cell systems sense and respond to chemotactic gradients to initiate cellular migration.
De novo transcriptome sequencing of Flammulina velutipes uncover candidate genes associated with cold‐induced fruiting
Authors: Wu Tuheng , Ye Zhiwei , Guo Liqiong , Yang Xueqin , Lin Junfang
Published: June 2018

To understand molecular mechanism of cold‐induced fruiting in Flammulina velutipes, which is one of most popular edible fungi in east Asia, de novo assembly of the F. velutipes transcriptome was carried out. There were 26,888,494 and 26,275,146 clean reads obtained from mycelium and primordia of F. velutipes, respectively. A total of 20,157 unigenes were de novo assembled and 15,058 of them were annotated. Moreover, 7935 unigenes were differentially expressed between mycelium and primordia, 4025 of them were up‐regulated and 3910 were down‐regulated. GO and KEGG pathway analysis of the differentially expressed unigenes indicated that functional groups associated with two‐component signaling pathway, calcium signaling, mitogen‐actived protein kinase pathway, molecular chaperones, cell wall and membrane system, play an important role in cold‐induced fruiting of F. velutipes. In this work 643 EST‐SSRs were identified in 20,157 unigenes and 1560 EST‐SSRs primers pairs were designed. Moreover, 5548 and 5955 SNPs were detected in mycelium and primordia, respectively. Consequently, results of this work can serve as a valuable resource for functional genomics study of cold‐induced fruiting in F. velutipes.
Long‐term evaluation (20 years) of the outcomes of subepithelial connective tissue graft plus coronally advanced flap in the treatment of maxillary single recession‐type defects
Authors: Pini Prato Giovan Paolo , Franceschi Debora , Cortellini Pierpaolo , Chambrone Leandro
Published: June 2018

Background

Subepithelial connective tissue graft with coronally advanced flap (SCTG + CAF) has been considered the best and most predictable root coverage procedure. Thus, the aims of this study are two‐fold: 1) to evaluate the long‐term outcomes following SCTG + CAF in the treatment of gingival recessions (GR) and 2) to explore the influence of several tooth/patient‐related factors on the stability of gingival margin at 1 year and at 5,10, 15, and 20 years after surgery.

Methods

Forty‐five patients with 45 maxillary GR (Miller's Class I or III) were treated with SCTG + CAF in a private practice between 1990 and 1997. Recession depth (RD), probing depth (PD), keratinized tissue (KT) width and patient/tooth‐associated variables were recorded for each GR at baseline, 1, 5, 10, 15, and 20 years after surgery. Parametric, non‐parametric, and logistic regression statistics were used throughout the study.

Results

A total of 21 Class I (44.67%) and 24 Class III (53.33%) GR were treated. Considering all the 45 GR, statistically significant improvements were found for RD in all evaluations (P < 0.05) compared with baseline data. Over the course of the study, mean root coverage (MRC) decreased from 74.23% (1 year) to 67.69% (20 years). Within maxillary Class I defects, complete root coverage (CRC) at 1‐year follow‐up was 57.14% (n = 12) and 47.62% (n = 10) at the end of study period, whereas MRC decreased from 82.37% to 77.62%, respectively. Within maxillary Class III recessions, CRC of 20.83% (n = 5) was found at both the 1‐year and the 20‐year follow‐ups. On the other hand, MRC decreased from 66.55% to 58.18%, respectively. The results of logistic regression analysis showed that the achievement of CRC was associated with sites not presenting interdental tissue loss (i.e., Class I, odds ratio: 5.031, P = 0.024), whereas GR recurrence appeared associated with sites with attached KT < 2 mm (i.e., 5‐, 10‐, 15‐ and 20‐year follow‐ups), to teeth presenting root steps (i.e., 10‐ and 20‐year follow‐ups), and smoking (i.e., 15‐year follow‐up).

Conclusions

Positive RD reduction and KT improvements achieved by SCTG + CAF at short‐term may be preserved long‐term with the majority of the treated sites not displaying relapse of the gingival margin. Teeth lacking a minimal 2‐mm width of attached KT and presenting non‐carious cervical lesions were more prone to develop an apical shift of the gingival margin during a 20‐year follow‐up period.
The correlation between visual fatigue and duration of viewing as assessed by brain monitoring
Authors: Yue Kang , Wang Danli , Hu Haichen , Fang Sun
Published: June 2018

Duration of viewing was considered as one of the most important factors of 3D visual fatigue. However, their relationship was not well studied. We proposed to use brain monitoring techniques to reveal more details about the variety of brain activity while watching three‐dimensional (3D) content. We investigated the spectral patterns in the electroencephalogram related to various duration of viewing and showed the power spectral density varied significantly along with the development of fatigue over occipital lobe, parietal lobe, and right frontal lobe. Moreover, we first described the trend of brain activity during 3D content viewing and revealed the location of significant components related to 3D visual fatigue. We believe that the absolute power describes more information and may be a better indicator of 3D visual fatigue assessment compared with relative power. We also first revealed the cortex location that is related to 3D visual fatigue. Our findings may help to define appropriate electroencephalogram features for online 3D visual fatigue detection while participants viewing 3D content.
Reactivity of cis‐platinum(II) complexes with 2‐(4‐substituted)phenylthiomethyl)quinoline nonleaving ligands toward thiourea nucleophiles
Authors: Mthiyane Wakhiwe M. , Mambanda Allen , Jaganyi Deogratius
Published: June 2018

The sequential substitution of aqua ligands from [Pt{2‐(phenylthiomethyl)quinoline}(H2O)2]CF3SO3, Pt(L1), [Pt{2‐(4‐tert‐butylphenylthiomethyl)quinoline}(H2O)2]CF3SO3 Pt(L2), and [Pt{2‐(4‐fluorophenylthiomethyl) quinoline}(H2O)2]CF3SO3 Pt(L3) by thiourea nucleophiles (Nu) was studied under pseudo–first‐order conditions as a function of concentration and temperature using stopped‐flow and UV‐visible spectrophotometric techniques. The observed pseudo–first‐order rate constants for the substitutions can be described by the rate law: kobs(1/2) = k2(1/2)[Nu], where the subscript denotes the consecutive substitution steps. The first aqua ligand was substituted opposite to the strong σ‐trans‐directing thioether followed by the aqua ligand opposite to the quinoline or pyridine moieties. Second‐order rate constants, k2(1st), for the substitution of the first aqua ligand by thiourea nucleophiles ranged between 9 and 22 M−1 s−1 for Pt(L1), 86 and 326 M−1 s−1 for Pt(L2), and 58 –287 M−1 s−1 for Pt(L3). The ranges of the second‐order rate constant, k2(2nd), were always lower than the k2(1st)’s and are 0.3‐9 M−1 s‐1 for Pt(L1), 2‐20 M−1 s−1 for Pt(L2), and 0.3‐5 M−1 s−1 for Pt(L3). Aqua substitution from Pt(L2) is slower for both steps than from Pt4, its pyridyl derivative from our previous study. A Job's method of continuous variation plot suggests a species with a metal‐to‐nucleophile ratio of 1:3 as the ultimate product of the chloride substitution from the Pt(II) complexes by the incoming thiourea nucleophiles. The high and negative activation entropy and low and positive activation enthalpy values support an associative mechanism of activation, characteristic of substitution reactions occurring in square‐planar complexes.
Kinetics and quantification of the electrophilic reactivities of substituted thiophenes and structure‐reactivity relationships
Authors: Souissi Salma , Gabsi Wahiba , Echaieb Abderraouf , Boubaker Taoufik
Published: June 2018

Second‐order rate constants (k1) have been measured spectrophotometrically for reactions of 2‐methoxy‐3‐X‐5‐nitrothiophene 1a‐c (X = NO2, CN, and COCH3) with secondary cyclic amines (pyrrolidine 2a, piperidine 2b, and morpholine 2c) in CH3CN and 91:9 (v/v) CH3OH/CH3CN at 20°C. The experimental data show that the rate constants (k1) values exhibit good correlation with the parameters of nucphilicity (N) of the amines 2a‐c and are consistent with the Mayr's relationship log k (20°C) = s(E + N). We have shown that the electrophilicity parameters E derived for 1a–c and those reported previously for the thiophenes 1d‐g (X = SO2CH3, CO2CH3, CONH2, and H) are linearly related to the pKa values for their gem‐dimethoxy complexes in methanol. Using this correlation, we successfully evaluated the electrophilicity E values of 12 structurally diverse electrophiles in methanol for the first time. In addition, a satisfactory linear correlation (r2 = 0.9726) between the experimental (log kexp) and the calculated (log kcalcd) values for the σ‐complexation reactions of these 12 electrophiles with methoxide ion in methanol has been observed and discussed.
Evaluating the impact of Uber on London's taxi service: A critical review of the literature
Authors: Skok Walter , Baker Samantha
Published: June 2018

Uber is a very well‐funded operation that has made innovative use of smartphone technology in the highly regulated and bureaucratic market of international taxi cab operations. The company has often adopted an aggressive approach when entering the marketplace in a given city, so the question arises as to how should the incumbent taxi trade react to such fierce competition that is popular with the public.

This paper describes a literature review related to the taxi and private hire industry in London that provides a foundation to answer this question. A second paper will present recommendations to help organisations prepare a response to the new competition.

From the collated journals, various themes emerged, and their reference lists were analysed to review recurring authors. The literature was organised into a thematic analysis grid to critique the content and analyse the implications for a project to evaluate the possible way forward for the taxi trade in response to Uber's aggressive approach. Six key themes were identified: disruptive innovation, sharing economy, business model, historical context, regulations, and labour.

The literature review was extended to include studies of the same area in the United States. Caution was exercised, as the U.S. market operates different ground transportation services and regulations. Nonetheless, comparisons were drawn regarding factors that were similar.

The identification of the six key themes will aid the taxi trade as well as researchers who wish to investigate the impact of Uber as and when it moves into new international markets.
Identification of the most limiting factor for rice yield using soil data collected before planting and during the reproductive stage
Authors: Wang Ming‐Ming , Rengasamy Pichu , Wang Zhi‐Chun , Yang Fu , Ma Hong‐Yuan , Huang Li‐Hua , Liu Miao , Yang Hao‐Yu , Li Jing‐Peng , An Feng‐Hua , Li Yang‐Yang , Liu Xiao‐Long , Liang Zheng‐Wei
Published: June 2018

Soil parameters, measured before crop planting, are typically used to quantify the relationship between soil properties and crop yield and to identify factors limiting crop yield. However, soil properties during sensitive stages of crop growth may have a greater effect on crop yield than the initial values. We determined if inclusion of soil properties, measured during the reproductive stage, could improve the accuracy of crop yield prediction. Classification and regression trees were used to determine the explanatory power of different soil and rice variables for predicting rice yield in alkaline salt‐affected paddy fields in northeast China. The traditional method explained 77.5% of the rice yield variation and identified soil CO32− in the 0‐ to 10‐cm soil layer, with single explanatory power of 53.4%, as the most important predictor. The whole explanatory power of the methods including soil variables during the reproductive stage and yield components, with/without soil variables before planting, increased to 81.3%. The residual sodium carbonate, measured in the 0‐ to 10‐cm soil layer during the reproductive stage, was identified as the most limiting factor due to its single maximum explanatory power of 60.5%. We conclude that inclusion of soil properties, measured during the reproductive stage, has potential for improving the rice yield prediction accuracy by enhancing the explanatory power in identification of the most limiting factor. These results encourage further investigation of the role of soil properties during sensitive stages of crop growth in crop yield prediction under different soil and climatic conditions.
Polyimide Fibers with High Strength and High Modulus: Preparation, Structures, Properties, and Applications
Authors: Zhang Mengying , Niu Hongqing , Wu Dezhen
Published: June 2018

High strength and high modulus polyimide (HSHMPI) fibers are a type of novel high‐performance organic fiber with an initial modulus higher than 90 GPa and extremely high tensile strength over 2.5 GPa realizing broad applications in the fields of electronic, engineering, aerospace, and atomic energy industries. There are currently two synthetic pathways, i.e., one‐step and two‐step methods, developed for the manufacture of HSHMPI fibers. An integrated fabrication process involving wet‐spinning followed by thermal imidization is accepted as a typical two‐step synthetic route for industrialization of HSHMPI fibers. In this article, the classification, synthetic method and technology, molecular structure, morphology, microstructures, and properties of HSHMPI fibers are summarized extensively. The effects of molecular structure and synthetic technology on the microstructures and overall performance of HSHMPI fibers are discussed. In addition, the trend in development and the application prospect of HSHMPI fibers are analyzed accordingly.
Genetic variation in the Hippo pathway and breast cancer risk in women of African ancestry
Authors: Wang Shengfeng , Huo Dezheng , Ogundiran Temidayo O. , Ojengbede Oladosu , Zheng Wei , Nathanson Katherine L. , Nemesure Barbara , Ambs Stefan , Olopade Olufunmilayo I. , Zheng Yonglan
Published: June 2018

Gene expression changes within the Hippo pathway were found to be associated with large tumor size and metastasis in breast cancer. The combined effect of genetic variants in genes of this pathway may have a causal role in breast cancer development. We examined 7086 SNPs that were not highly correlated (r2 < 0.8) in 35 Hippo pathway genes using data from the genome‐wide association study of breast cancer from the Root Consortium, which includes 3686 participants of African ancestry from Nigeria, United States of America, and Barbados: 1657 cases (403 estrogen receptor‐positive [ER+], 374 ER−) and 2029 controls. Gene‐level analyses were conducted using improved AdaJoint test for large‐scale genetic association studies adjusting for age, study site and the first four eigenvectors from the principal component analysis. SNP‐level analyses were conducted with logistic regression. The Hippo pathway was significantly associated with risk of ER+ breast cancer (pathway‐level P = 0.019), with WWC1 (Padj = 0.04) being the leading gene. The pathway‐level significance was lost without WWC1 (P = 0.12). rs147106204 in the WWC1 gene was the most statistically significant SNP after gene‐level adjustment for multiple comparisons (OR = 0.53, 95%CI = 0.41–0.70, Padj = 0.025). We found evidence of an association between genetic variations in the Hippo pathway and ER+ breast cancer. Moreover, WWC1 was identified as the most important genetic susceptibility locus highlighting the importance of genetic epidemiology studies of breast cancer in understudied populations.
EWS‐FLI1 reprograms the metabolism of Ewing sarcoma cells via positive regulation of glutamine import and serine‐glycine biosynthesis
Authors: Sen Nirmalya , Cross Allison M. , Lorenzi Philip L. , Khan Javed , Gryder Berkley E. , Kim Suntae , Caplen Natasha J.
Published: June 2018

Ewing sarcoma (EWS) is a soft tissue and bone tumor that occurs primarily in adolescents and young adults. In most cases of EWS, the chimeric transcription factor, EWS‐FLI1 is the primary oncogenic driver. The epigenome of EWS cells reflects EWS‐FLI1 binding and activation or repression of transcription. Here, we demonstrate that EWS‐FLI1 positively regulates the expression of proteins required for serine‐glycine biosynthesis and uptake of the alternative nutrient source glutamine. Specifically, we show that EWS‐FLI1 activates expression of PHGDH, PSAT1, PSPH, and SHMT2. Using cell‐based studies, we also establish that EWS cells are dependent on glutamine for cell survival and that EWS‐FLI1 positively regulates expression of the glutamine transporter, SLC1A5 and two enzymes involved in the one‐carbon cycle, MTHFD2 and MTHFD1L. Inhibition of serine‐glycine biosynthesis in EWS cells impacts their redox state leading to an accumulation of reactive oxygen species, DNA damage, and apoptosis. Importantly, analysis of EWS primary tumor transcriptome data confirmed that the aforementioned genes we identified as regulated by EWS‐FLI1 exhibit increased expression compared with normal tissues. Furthermore, retrospective analysis of an independent data set generated a significant stratification of the overall survival of EWS patients into low‐ and high‐risk groups based on the expression of PHGDH, PSAT1, PSPH, SHMT2, SLC1A5, MTHFD2, and MTHFD1L. In summary, our study demonstrates that EWS‐FLI1 reprograms the metabolism of EWS cells and that serine‐glycine metabolism or glutamine uptake are potential targetable vulnerabilities in this tumor type.
Numerical treatment of two‐parameter singularly perturbed parabolic convection diffusion problems with non‐smooth data
Authors: Chandru M. , Das P. , Ramos H.
Published: June 2018

In the present work, we consider a parabolic convection‐diffusion‐reaction problem where the diffusion and convection terms are multiplied by two small parameters, respectively. In addition, we assume that the convection coefficient and the source term of the partial differential equation have a jump discontinuity. The presence of perturbation parameters leads to the boundary and interior layers phenomena whose appropriate numerical approximation is the main goal of this paper. We have developed a uniform numerical method, which converges almost linearly in space and time on a piecewise uniform space adaptive Shishkin‐type mesh and uniform mesh in time. Error tables based on several examples show the convergence of the numerical solutions. In addition, several numerical simulations are presented to show the effectiveness of resolving layer behavior and their locations.
Rhinoceros (Stephanorhinus hemitoechus) exploitation in Level F at the Caune de l'Arago (Tautavel, Pyrénéés‐Orientales, France) during MIS 12
Authors: Chen Xi , Moigne Anne‐Marie
Published: June 2018

Caune de l'Arago is a Middle Pleistocene site in Southern France, where Acheulean artefacts and hominin fossils were excavated. Rhinoceros (Stephanorhinus hemitoechus) remains from Level F (MIS 12) were studied from a zooarchaeological and taphonomic perspective to investigate the potential human exploitation of this large taxon. The well‐represented butchering marks, as well as scarce carnivore marks, indicate primary access to rhinoceros carcasses by hominins. The juvenile‐dominated mortality profile further suggests aggressive scavenging or occasional opportunistic hunting. Furthermore, differential skeletal representation shows that humans selectively transported the nutrient‐rich body sections. In addition, thorough processing of the carcasses for consumption inside the cave is highlighted by the frequent cut marks, intensive fragmentation, and regular spatial distribution. The analyses of the Arago Level F rhinoceros confirm the rhinoceros exploitation by humans during the Lower Palaeolithic; however, the rhinoceros mortality profile differs from that of large mammals such as equids, argali, and all other game species of this archaeological layer. Caune de l'Arago is the earliest hominin site where the systematic exploitation of rhinoceros has been documented.