bluuebunny/crossref_metadata_2025 huggingface dataset:
Asymmetry of the group context effect on delay discounting
Authors: Yi Richard , Lee Juhan , Bettis Jama
Published: August 2019

Binary choice delay discounting tasks require participants to indicate preference between smaller, immediate, and larger, delayed rewards. Previous research indicates that when the delayed reward is shared with others, the delayed outcome is preferred compared with when the outcomes are for the self only, resulting in lower rates of delay discounting. The present series of studies sought to replicate and extend this finding. Study 1 compared delay discounting on a standard task in which both immediate and delayed outcomes are for the self and a group context task where the delayed outcome was shared with one other person. Replicating previous results, group context resulted in lower rates of delay discounting, and this effect was independent of how the shared outcome was presented. Study 2 compared delay discounting on a standard task and a group context task where the immediate outcome was shared. In contrast to Study 1, group context resulted in higher rates of delay discounting, suggesting that preference in intertemporal choice tracks the shared outcome. Moreover, this effect was not independent of how the shared outcome was presented. This is the first study to reveal that group context, when applied to the immediate outcome, can result in higher rates of delay discounting.
What Is and Isn't in a Name
Authors: Frumer Yulia
Published: August 2019

Although I remain sympathetic to the narrative behind the notion of “History of Knowledge,” I argue against redrawing the disciplinary boundaries around “knowledge,” as opposed to retaining the term “science.” This is not because I think there is no place for a “history of knowledge,” and not because I am concerned that such a redrawing of disciplinary boundaries would open the floodgates of “anything goes.” Rather, I am doubtful that problems of demarcation and exclusion can be resolved solely by changing a name. I draw on my personal experience as an East Asianist to suggest that the challenges I faced trying to fit into the community of historians of science and technology would not have been solved by renaming the discipline. At the same time, I also argue that changes can and do happen without a change of name. And finally, I maintain that the word “science” has important connotations that we do not want to give up.
Adult height, body mass index change, and body shape change in relation to esophageal squamous cell carcinoma risk: A population‐based case‐control study in China
Authors: Yang Xiaorong , Zhang Tongchao , Yin Xiaolin , Yuan Ziyu , Chen Hui , Plymoth Amelie , Jin Li , Chen Xingdong , Lu Ming , Ye Weimin
Published: August 2019

The relationship between risk of esophageal squamous cell carcinoma (ESCC) and adult height, changes in individual body mass index (BMI) and body shape is not established. We performed a large population‐based case‐control study, which enrolled a total of 1414 ESCC cases and 1989 controls in a high‐incidence area in China. Using face‐to‐face interview with a structured questionnaire, information on participants' heights, weights, and perceived body shapes at 20 years of age was collected. Additionally, data on weight and perceived body shape among the same participants 10 years prior to ascertainment were collected using the same method. Odd ratios (ORs) of ESCC risk in relation to BMI and body shape were estimated using unconditional logistic regression models. The adjusted results indicated that ESCC risk in adults rapidly rose as height increased, plateauing at 170 cm among men and 157 cm among women. Among participants who were underweight, normal weight, or thinner than body shape 4, body weight loss was associated with increased risk of ESCC, and body weight gain was associated with decreased incidence of ESCC (ORs ranging from 0.40 to 0.76). Notably, however, changes in body weight did not significantly affect ESCC risk among participants who were overweight, obese, or larger than body shape 3. Maintaining a fit body shape and a reasonable BMI is advisable and of vital importance to reduce the risk of ESCC, especially in high‐risk areas.
The piloting of a brief relational psychodynamic protocol (psychodynamic addiction model) for problem gambling and other compulsive addictions: A retrospective analysis
Authors: Mooney Angela , Roberts Amanda , Bayston Andrew , Bowden‐Jones Henrietta
Published: August 2019

The paper describes a treatment pilot for gambling and compulsive addiction within an NHS problem gambling clinic. The pilot study used a brief relational psychodynamic treatment protocol specifically designed to meet the needs of a group of patients who had not responded to CBT and who had other addictions or co‐morbidities. Seventy‐two (n = 72) patients were offered 12 sessions of therapy by four psychodynamic counsellors. Results were assessed using scores from a pre‐ and post‐treatment patient health questionnaire, the generalised anxiety disorder—7 (GAD‐7) and the Problem Gambling Severity Index (PGSI). Weekly feedback and supervision from counsellors and patients were used to assess the treatment model. The results highlighted that the psychodynamic addiction model was associated with reduced depression (Mean = 14.9; SD: 6.7), anxiety (Mean = 11.5; SD: 5.9), and gambling severity (p < .001), suggesting that a relational psychodynamic treatment is needed for complex patients with compulsive addiction, where CBT had not been successful. These results also highlight the importance of the therapeutic relationship as a critical factor in the treatment of patients with compulsive addiction problems.
Subtle forms of racism in strategy documents concerning Roma inclusion
Authors: Popoviciu Salomea , Tileagă Cristian
Published: August 2019

This paper explores the ways in which national governments address the social inclusion of disadvantaged and disenfranchised groups in official strategy documents of the state. Data for this study come from a corpus of four key government strategy papers concerning Roma inclusion published by the Romanian Government between 2001 and 2015. This paper specifically looks at the ways in which strategy documents frame the problem of “crime” in the context of Roma inclusion. Texts were analysed using a critical frame analysis approach complemented by insights from discursive research. The findings highlight that although generally government policy on the Roma adopts and promotes a progressive/liberal agenda that aligns with EU strategic goals, pronounced ambivalence towards Roma people and subtle forms of racism are still present and persist.
Graphostromols A–K, Eleven New Chained Polyketides from the Deep‐Sea‐Derived Graphostroma sp
Authors: Niu Siwen , Xie Chun‐Lan , Xia Jin‐Mei , Zhong Tianhua , Luo Zhuhua , Shao Zongze , Yang Xian‐Wen
Published: August 2019

Chromatographic separation of the AcOEt extract of the fermented cultures of the deep‐sea‐derived fungus Graphostroma sp. resulted in the isolation of 11 new chained polyketides, namely graphostromols A–K (1–11). The structures of the new compounds were established by the extensive analyses of their NMR and HR‐ESI‐MS data. The absolute configuration at C‐11 in 1 was determined on the basis of the modified Mosher's method. Compounds 1–5, bearing a 2,2,10,10‐tetramethyldodecane skeleton, were discovered for the first time from nature. All isolates were evaluated for their cytotoxicities against five different cancer cell lines (HeLa, Eca‐109, Biu‐87, Bel‐7402, and PANC‐1). However, none showed positive effects.
Different properties between spontaneous and volume‐activated chloride currents in human nasopharyngeal carcinoma and its normal counterpart cells
Authors: Tang Xinwei , Feng Jiezhu , Peng Zihan , Hou Xiuying , Zuo Wanhong , Chen Lixin , Wang Liwei , Zhu Linyan
Published: August 2019

Although the spontaneous chloride currents (SCC) have been well studied in the normal cells, its properties and roles in neoplasms cells are still unknown. Here, we found that the SCC was manifested in the poorly differentiated human nasopharyngeal carcinoma CNE‐2Z cells, with some differences such as lower occurrence and bigger current density than those of the volume‐activated chloride currents (VACC). NPPB, a chloride channel blocker, inhibited the SCC much stronger than the VACC. Down‐regulation of chloride channel ‐3 (ClC‐3), a volume and mechanically dependent ion channel, could significantly decrease the VACC, but not in SCC. The occurrence, latency, and mean density of the SCC were much lower in the normal nasopharyngeal NP69‐SV40T cells than those in CNE‐2Z cells. Our results demonstrated that the spontaneous electrical reactivity of neoplasm cells is higher than that of normal cells, which probably relates to their high physiological activity of neoplasm cells.

Significance of the study

Spontaneous chloride currents (SCC) are well known in excitable tissues and regulate a variety of physiological and pathophysiological processes. During our researching on the volume‐activated chloride currents (VACC) in human nasopharyngeal carcinoma CNE‐2Z cells, SCC could be also observed with different properties from VACC. Meanwhile, the occurrence, latency, and mean density of the SCC were much higher in CNE‐2Z cells than those in normal nasopharyngeal NP69‐SV40T cells. Our results revealed the expression and characteristics of SCC in carcinoma cells and provided a preliminary experimental basis for further exploring the function of SCC in tumour cell biology.
Electrochemical Activity Determination of Catechol‐O‐methyl Transferase by Selective Dopamine Detection
Authors: Göbel Gero , Talke Anja , Ahnert Uwe , Lisdat Fred
Published: August 2019

For the treatment of Parkinson's disease, as one of the most frequent diseases of the central nervous system, several key enzymes for dopamine metabolism [e. g. catechol‐O‐methyl transferase (COMT)] are drug targets. For an efficient and long‐lasting treatment, the activity of this enzyme should be monitored. In this study, an electrochemical approach using differential pulse voltammetry (DPV) is introduced for the activity determination. The applied electrode material, fluorine‐doped tin oxide (FTO), is characterized by a clear discrimination between substrate and product of COMT, a high stability of the dopamine signal during consecutive measurements, and a linear dependency on the dopamine concentration in the range of the maximum reaction rate of COMT. Despite these advantageous results, dopamine detection in the complete activity assay is influenced by each of the added essential assay components, even though none of the added components reveal a current signal at the FTO electrode itself. After adjusting the potential range and the assay composition, these effects can be circumvented. By following the dopamine concentrations during COMT action, it can be shown that the activity of COMT can be detected by using differential pulse voltammetry (DPV) at an FTO electrode and, by analyzing different COMT amounts, quantification can be demonstrated.
Electrodeposited Cu2O Films on Gas Diffusion Layers for Selective CO2 Electroreduction to Ethylene in an Alkaline Flow Electrolyzer
Authors: Anastasiadou Dimitra , Schellekens Maarten , de Heer Michiel , Verma Sumit , Negro Emanuela
Published: August 2019

Novel electrodes for the electroreduction of CO2 were prepared by the electrodeposition of copper (I) oxide (Cu2O) catalytic films on a gas diffusion layer. Different electrodes were prepared by varying the deposition time, corresponding to catalyst loadings of 0.37, 0.74, 2.22, 3.70 mg cm−2 and a total charge density of 0.5, 1, 3, and 5 C cm−2, respectively. The electrodes were characterized with SEM, XRD, and UPD. The effect of catalyst loading on the selectivity towards ethylene was investigated in an alkaline flow electrolyzer under ambient conditions. The electrodes were found to be highly selective (>60 %) towards ethylene. The 1 C cm−2 electrode reached Faradaic efficiency values as high as 67 % at industrially relevant current densities of 183 mA cm−2, −0.8 V cathode overpotential and 36 % cell energy efficiency. This performance was attributed to the interplaying role of applied potential, local pH, availability of active sites, and reduced CO2 mass transport limitations.
Stereoselective Thioconjugation by Photoinduced Thiol‐ene Coupling Reactions of Hexo‐ and Pentopyranosyl d‐ and l‐Glycals at Low‐Temperature—Reactivity and Stereoselectivity Study
Authors: Kelemen Viktor , Bege Miklós , Eszenyi Dániel , Debreczeni Nóra , Bényei Attila , Stürzer Tobias , Herczegh Pál , Borbás Anikó
Published: August 2019

A comprehensive optimization and mechanistic study on the photoinduced hydrothiolation of different d‐ and l‐ hexo‐ and pentoglycals with various thiols was performed, at the temperature range of RT to −120 °C. Addition of thiols onto 2‐substituted hexoglycals proceeded with complete 1,2‐cis‐α‐stereoselectivity in all cases. Hydrothiolation of 2‐substituted pentoglycals resulted in mixtures of 1,2‐cis‐α‐ and ‐β‐thioglycosides of varying ratio depending on the configuration of the reactants. Hydrothiolation of unsubstituted glycals at −80 °C proceeded with excellent yields and, except for galactal, provided the axially C2‐S‐linked isomers with high selectivity. Cooling was always beneficial to the efficacy, increased the yields and in most cases significantly raised the stereoselectivity. The suggested mechanism explains the different conformational preferences of the intermediate carbon‐centered radicals, which is a crucial factor in the stereoselectivity of the reactions.
Simultaneous determination of guaifenesin enantiomers and ambroxol HCl using 50‐mm chiral column for a negligible environmental impact
Authors: Tantawy Mahmoud A. , Yehia Ali M. , Aboul‐Enein Hassan Y.
Published: August 2019

Chiral stationary phases are conveniently used for enantiomeric separation of drugs by liquid chromatography. Consumption of large volumes of hazardous solvents is considered as a common challenge for the sustainability of this technique. To this end, a columnar chromatography has been adopted using 50‐mm‐length stationary phases. The study comprised five Phenomenex Lux cellulose‐ and amylose‐based columns for the separation of guaifenesin (GUA) enantiomers. In addition, an experimental design was used to optimize the gradient profile for the separation of racemic GUA and ambroxol HCl (AMB) binary mixture. The chromatographic method was achieved using Lux Cellulose‐1 (50 × 4.6 mm) as a chiral stationary phase and ethanol/water as a mobile phase with linear gradient elution of 20% to 70% ethanol in 6 minutes at a flow rate of 1.0 mL min−1and UV detection at 270 nm. Linearity ranges were found to be 50 to 1000 μg mL−1and 15 to 450 μg mL−1for each GUA enantiomer and AMB, respectively. Environmental, health and safety tool was used to assess and compare greenness of the proposed and reported methods. Short column indeed reduces the environmental impact by decreasing waste by about 60% and utilizing only 1‐mL ethanol in the mobile phase. The proposed method is a safer alternative for the simultaneous determination of drugs in their combined pharmaceutical formulation. The method has been validated and compared favorably with a reported one.
Essentielle Spurenelemente und toxische Metallverbindungen
Authors: Hufnagel Matthias , Niemand Rebecca K. , Strauch Bettina M. , Hartwig Andrea
Published: August 2019

Metallverbindungen sind ubiquitär in der Erdkruste vorhanden und unverzichtbar für viele technische Anwendungen. Auch Spurenelemente sind in biologischen Systemen essentiell. Allerdings sind einige Metallverbindungen toxisch und sogar krebserzeugend, und auch bei Spurenelementen kommt der zellulären Homöostase eine entscheidende Rolle zu. Ein wichtiger Aspekt ist die Rolle von Metallionen bei der Aufrechterhaltung der Stabilität des Genoms. Während Spurenelemente beispielsweise als Bestandteile von Zink‐bindenden Domänen entscheidend zum korrekten Ablauf von DNA‐Reparaturprozessen und Tumorsuppressorfunktionen beitragen, sind es genau diese Strukturen, die besonders empfindliche Angriffspunkte für toxische Metallionen darstellen können. Aber auch Spurenelemente können toxisch sein, wenn die bei ausgewogener Ernährung gut regulierten intrazellulären Gehalte beispielsweise durch zu hohe Aufnahmemengen oder durch nicht physiologische Aufnahmewege deutlich überschritten werden. Einen vielversprechenden Ansatz zur Aufklärung von Wirkungsmechanismen bietet eine kürzlich etablierte High‐Throughput‐RT qPCR‐Methode, die es ermöglicht, den Einfluss auf 95 ausgewählte Gene, die eine wichtige Rolle bei der Aufrechterhaltung der genomischen Stabilität spielen, in 96 Proben parallel zu untersuchen. Neben der Erstellung toxikologischer „Fingerprints“ ermöglicht dieses System die Betrachtung von Dosis‐Wirkungs‐Beziehungen, vergleichende Untersuchungen unterschiedlicher Metallspezies sowie detaillierte mechanistische Analysen beispielsweise metallhaltiger Nanopartikel. Alle diese Aspekte sind wichtige Voraussetzungen für eine wissenschaftlich basierte Nutzen‐Risiko‐Bewertung.
Hypertriglyceridemia is associated with an increased risk of peripheral arterial revascularization in high‐risk statin‐treated patients: A large administrative retrospective analysis
Authors: Toth Peter P. , Philip Sephy , Hull Michael , Granowitz Craig
Published: August 2019

Background

Peripheral artery disease (PAD) is common, and although it is associated with cardiovascular (CV) morbidity, mortality, reduced quality of life, and increased health care burden, PAD data are relatively scarce. Elevated triglycerides (TG) are associated with and are a risk factor for PAD.

Hypothesis

Large administrative retrospective data may provide further insight into the relationship between hypertriglyceridemia and peripheral arterial revascularization in high‐risk statin‐treated patients.

Methods

This retrospective administrative claims analysis of the Optum Research Database included statin‐treated patients aged ≥45 years with diabetes and/or atherosclerotic CV disease enrolled in 2010 and followed for ≥6 months. Patients with TG ≥150 mg/dL were propensity score‐matched to a comparator cohort with TG <150 mg/dL and high‐density lipoprotein cholesterol >40 mg/dL (n = 23 181 in each cohort). A sub‐analysis was conducted in patients with TG 200‐499 mg/dL and a matched comparator cohort (n = 10 990). Clustered P‐values were calculated using a Cox proportional hazard model with cohort as the independent variable (α, 0.05).

Results

Multivariate analysis showed a 37% higher rate of peripheral arterial revascularization in the elevated‐TG cohort vs the comparator cohort (hazard ratio [HR] 1.370, 95% confidence interval [CI] 1.263‐1.486; P < .001). Results in the high‐TG sub‐cohort were similar, with a 49% higher rate of revascularization vs the comparator cohort (HR 1.489; 95% CI, 1.348‐1.644; P < .001).

Conclusions

This large administrative retrospective analysis of high‐risk statin‐treated patients showed that elevated TG (≥150 mg/dL) and high TG (200‐499 mg/dL) were significant predictors of peripheral arterial revascularization; this warrants further study.
Anatomically based simulation of hepatic perfusion in the human liver
Authors: Ma Renfei , Hunter Peter , Cousins Will , Ho Harvey , Bartlett Adam , Safaei Soroush
Published: August 2019

Liver structures of a healthy subject are digitised and segmented from computed tomography (CT) images, and hepatic perfusion is modelled in the hepatic artery and portal vein of the healthy subject with structured tree‐based outflow boundary conditions. This self‐similar structured tree is widely used in the literature, eg, blood flow simulation in larger systemic arteries and cerebral circulation, and is used in this study to model the effect of the smaller hepatic arteries and arterioles, as well as the smaller hepatic portal veins and portal venules. Physiologically reasonable results are obtained. Since the structured tree terminates at the size of the microvasculature system in liver lobules, the structured tree boundary condition will enable the proposed organ‐level model of hepatic arterial flow to be easily connected to tissue‐level models of liver lobules. Blood flow in the hepatic vein is also modelled in this subject with three‐element Windkessel model as outflow boundary conditions. The benefit of integrating the perfusion in all hepatic vascular vessels is that it helps us analyse some complicated clinical phenomenon more efficiently, eg, one possible application is to obtain the portal pressure gradient (PPG) to help examine the reliability of hepatic venous pressure gradient (HVPG) as an indirect measure of portal pressure. Moreover, since four to six generations of hepatic vessels, which are sufficient for liver classification analysis, were employed in the model, this study is setting the computational foundation of a potentially handy surgical tool.
Perceptions of the “anorexic voice”: A qualitative study of health care professionals
Authors: Graham Meghan R. , Tierney Stephanie , Chisholm Amy , Fox John R.E.
Published: August 2019

People with anorexia nervosa (AN) often report experiencing a highly critical inner voice (AV) focused on their eating, shape, and weight. There are promising preliminary findings for its role in the treatment of AN, and the support of staff is vital for the AV to be embedded in treatment, but their views remain unknown. The aims of this study were to undertake a qualitative exploration of the perceptions of the AV among health care professionals (HCPs) in specialist eating disorder services. A thematic analysis was applied to interviews with 15 HCPs, including nurses, therapists, psychiatrists, health care assistants, psychologists, and dietitians. Two overarching themes were identified: “The AV is a vehicle for increasing compassion” and “It's not a one‐size‐fits‐all.” The AV was seen as a means of developing and sustaining compassion, but participants noted that it does not resonate for all clients. All HCPs in this study believed that there was potential benefit in utilizing the AV in their work with people with AN, and it is likely that doing so would help to reduce burnout and frustration within clinical teams.
Corporate social responsibility “glocalisation”: Evidence from the international construction business
Authors: Ye Meng , Lu Weisheng , Flanagan Roger , Chau Kwong Wing
Published: August 2019

This paper aims (a) to enrich the corporate social responsibility (CSR) globalisation–localisation dyad (called “glocalisation”) by positioning it amid relevant theoretical discourses and (b) to map out CSR glocalisation patterns by focusing on international construction as a revealing business sector. It does so by triangulating field studies with content analyses of 68 international construction companies' (ICCs) CSR reports over 7 years (2011–2017) assisted by a text mining approach. By examining how categories of CSR issue are valued in different host countries, the research positions CSR glocalisation in a four‐quadrant grid model to illustrate their relationships. It is found that ICCs adopt glocalisation to strike a balance between CSR globalisation/standardisation and localisation/contextualisation to enhance the consistency and efficiency of their CSR strategies while maintaining responsiveness to the local environment. Demystification of the concept of CSR glocalisation will encourage further theoretical debate and practical applications of CSR and sustainable development in the international construction business.
Electrohydrogenation of Carbon Dioxide using a Ternary Pd/Cu2O–Cu Catalyst
Authors: Li Jing , Guo Si‐Xuan , Li Feng , Li Fengwang , Zhang Xiaolong , Ma Jiantai , MacFarlane Douglas R. , Bond Alan M. , Zhang Jie
Published: August 2019

A simple one‐pot method has been developed to synthesize a palladium/cuprous oxide‐copper (Pd/Cu2O–Cu) material with a well‐defined structure, by modification of Cu2O–Cu with Pd through a galvanic replacement reaction. Compared with the well‐known copper/cuprous oxide (Cu/Cu2O) catalysts, the Pd/Cu2O–Cu material can catalyze the electroreduction of CO2 into C1 products with much higher faradaic efficiencies at lower overpotentials in a CO2‐saturated 0.5 m NaHCO3 solution. In particular, the highest faradaic efficiencies of 92 % for formate and 30 % for methane were achieved at −0.25 and −0.65 V (vs. the reversible hydrogen electrode), respectively. The improvement is suggested to be the result of a synergistic effect between PdH and the catalytically active copper sites during electrochemical CO2 reduction.
Hierarchically Porous Co−N−C Cathode Catalyst Layers for Anion Exchange Membrane Fuel Cells
Authors: Zhang Junfeng , Zhu Weikang , Pei Yabiao , Liu Yang , Qin Yanzhou , Zhang Xiangwen , Wang Qingfa , Yin Yan , Guiver Michael D.
Published: August 2019

As a new class of metal–nitrogen–carbon (M−N−C) material with 3 D microstructure, zeolitic imidazolate frameworks (ZIFs) are used to synthesize highly active electrocatalysts for the oxygen reduction reaction, as substitutes for commercial Pt/C in anion exchange membrane fuel cells. However, to form an effective catalyst layer (CL), the relationship between the microstructure of the ZIF‐derived catalyst and the fuel cell performance must be investigated. In this work, a hierarchically porous CL based on the carbon black (CB)‐controlled synthesis of a Co‐based ZIF (denoted as ZIF‐CB‐700) is constructed to optimize the triple‐phase boundary (TPB) and mass transfer. The power density at 40 °C of ZIF‐CB‐700 (95.4 mW cm−2) as cathode catalyst is about 4 times higher than that of the catalyst synthesized in the absence of CB and is comparable to that of the commercial 60 % Pt/C catalyst (112.0 mW cm−2). Both online and offline measurements suggest that the morphology and microstructure of the CL is crucial to form an active TPB region, dominating the fuel cell performance rather than only the high catalyst activity.
Polymer‐Anchored Bifunctional Pincer Catalysts for Chemoselective Transfer Hydrogenation and Related Reactions
Authors: Mujahed Shrouq , Valentini Federica , Cohen Shirel , Vaccaro Luigi , Gelman Dmitri
Published: August 2019

A series of polymer‐supported cooperative PC(sp3)P pincer catalysts was synthesized and characterized. Their catalytic activity in the acceptorless dehydrogenative coupling of alcohols and the transfer hydrogenation of aldehydes with formic acid as a hydrogen source was investigated. This comparative study, examining homogeneous and polymer‐tethered species, proved that carefully designing a link between the support and the catalytic moiety, which takes into consideration the mechanism underlying the target transformation, might lead to superior heterogeneous catalysis.
Understanding the Oxygen Reduction Reaction Activity and Oxidative Stability of Pt Supported on Nb‐Doped TiO2
Authors: He Cheng , Sankarasubramanian Shrihari , Matanovic Ivana , Atanassov Plamen , Ramani Vijay
Published: August 2019

Invited for this month′s cover are the groups of Prof. Vijay Ramani at Washington University in St. Louis and Prof. Plamen Atanassov at the University of New Mexico (presently the University of California, Irvine). The image represents a fuel cell‐powered car with a highly durable and active catalyst. The Full Paper itself is available at 10.1002/cssc.201900499.
Ant diversity patterns across tropical elevation gradients: effects of sampling method and subcommunity
Authors: Longino John T. , Branstetter Michael G. , Ward Philip S.
Published: August 2019

Local diversity may be influenced by niche assembly processes involving competition for limited resources, or by niche conservatism and the length of time clades have had to diversify. Mid‐elevation peaks in ant diversity on wet forest elevational gradients are most consistent with niche conservatism effects. However, it is possible that subsets of the ant community vary in the degree to which niche assembly processes are important, and this may be revealed by sampling methods that bias toward particular subsets. A previous study of ant‐elevation patterns in Middle American wet forest relied on Winkler sampling, a method that samples much of the ant community that occurs in leaf litter and rotten wood on the forest floor. Here, we evaluate richness patterns at the same sites as the previous study, using two alternative methods: baiting and beating. Baiting attracts ants to a concentrated resource and might be expected to attract a community more shaped by competitive interactions. Diversity patterns at baits were nearly identical to patterns from Winkler samples, for all ants combined and for the genus Pheidole, which are abundant omnivorous ants that are among the most common at baits. There was no evidence that stronger competitive effects influenced the shape of the diversity curve. Beating samples capture ants that forage on low vegetation, a distinct arboreal community with lower phylogenetic diversity than litter ants and inhabiting a more variable microclimate. Arboreal ants differed from litter ants in having a less distinct mid‐elevation peak, with less of a decline from 500 m to sea level. The lowland decline in litter ant diversity may be caused by the recent upslope shift in temperature associated with the current interglacial period. Arboreal ants may be buffered from this effect by adaptation to canopy life, tolerating broader extremes of temperature, or by high rates of dispersal from warmer regions.
A roadmap for exploring the thematic content of ecology journals
Authors: Knott Jonathan , LaRue Elizabeth , Ward Samuel , McCallen Emily , Ordonez Kimberly , Wagner Franklin , Jo Insu , Elliott Jessica , Fei Songlin
Published: August 2019

Ecologists—especially those new to the field—are tasked with finding relevant literature matching their research interests and deciding upon a suitable venue for the publication of their work. To provide a roadmap for early career researchers to identify journals aligned with their interests, we analyzed major research themes found across the top 30 ecology journals and three high‐impact multi‐disciplinary journals (Nature, PNAS, and Science), utilizing an automated content analysis (ACA) of 84,841 article abstracts, titles, and author keywords published over the last four decades. Journals clustered into 10 distinct groups based on 46 research themes identified by ACA. We examined the frequency of ecological themes in each of these journal groups to identify the journals most associated with each theme. We found three themes (anthropogenic impacts, disease, and traits) that occurred at a high frequency in the high‐impact multi‐disciplinary journal group containing Nature, PNAS, and Science. Themes that increased in frequency over the last four decades, such as climate change, traits, anthropogenic, and cellular biology, were found more often in journals with higher impact factors, indicating that emerging research themes in ecology will likely become of interest to a broader readership over time. Our study provides a thematic review as a potential roadmap for junior ecologists to browse and publish journal articles.
If a tree falls in a forest: implications of forest structure persistence for the Pacific marten (Martes caurina)
Authors: Delheimer Matthew S. , Moriarty Katie M. , Linnell Mark A. , Woodruff Bryce V.
Published: August 2019

A global decline in large trees, largely driven by anthropogenic influences, has potentially dire consequences for cavity‐dependent wildlife. For several species of conservation concern in western North America, including Pacific martens (Martes caurina), fishers (Pekania pennanti), and spotted owls (Strix occidentalis), large live and dead trees (snags) with cavities are forest structural elements that are requisite to fulfilling life history requirements. More than a century may be necessary for trees to develop cavities of a suitable size for use by martens, fishers, and owls, yet the relative amount of time that such trees persist as usable prior to senescence is largely unknown, despite the implications for how forests are managed as habitat for these wildlife species. To address this uncertainty, in 2016, we re‐located 44 live trees and snags identified as marten rest structures between 2009 and 2012 in the Lassen National Forest, California. Upon re‐location, we assessed structure persistence by determining whether structures had changed type (e.g., a live tree that died and transitioned to a snag) or usability (any structure that was degraded to a point where it was no longer usable by a marten). After 5–7 yr, 25% (n = 11) of marten rest structures changed type and 16% (n = 7) appeared to be unusable—a stark contrast compared to a similar study investigating persistence of fisher rest structures, which documented one‐third of the change in structure type and no change in usability over roughly twice the return interval (8–12 yr). Our results emphasize the vast disparity between the lengthy period required for trees to become suitable for marten use and the potentially short period for which they may remain usable. We suggest that forest managers consider the importance of these fine‐scale forest structural elements when developing broad‐scale strategies to reduce fire risk and improve resilience in western North American forests.
Factors influencing blue carbon accumulation across a 32‐year chronosequence of created coastal marshes
Authors: Abbott Katherine M. , Elsey‐Quirk Tracy , DeLaune Ronald D.
Published: August 2019

Saline coastal marshes are blue carbon ecosystems with relatively high soil carbon (C) stocks and high rates of soil C accumulation. Loss of saline wetlands due to relative sea‐level rise, land‐use change, and hydrologic alterations liberates previously stored C and reduces the capacity for future C sequestration. Widespread wetland loss has prompted marsh restoration and creation projects around the world; however, little is known about the timescale and capacity for created marshes to function as blue C sinks and the role of environmental conditions in mediating soil C accumulation in restoration sites. Using a chronosequence of five created saline marshes ranging in age from 5 to 32 yr and two adjacent natural reference marshes in southwest Louisiana, USA, short‐ and longer‐term C accumulation rates (SCAR and LCAR, respectively) were determined using feldspar marker horizons and peat depth in cores at six locations in each marsh. Created marshes ranged in elevation from −12 to 41 cm (NAVD88) and supported assorted plant community compositions driven by local environmental conditions. SCAR ranged from 75 to 430 g C·m−2·yr−1, which were comparable in the two youngest and two oldest marshes. Longer‐term CAR ranged from 18 to 99 g C·m−2·yr−1 but did not significantly differ among marshes of different ages. Our findings indicate that LCAR in these created marshes were influenced by site‐specific environmental conditions (i.e., stem density and mineral sediment) rather than marsh age. Results suggest that conditions appropriate for the establishment of vegetation with high stem densities, such as Distichlis spicata and Spartina patens, may facilitate higher LCAR in created marshes, which may be useful for restoration project planning and mitigation of climate change.
The Scope of Application of Macrocyclic Polyamines Beyond Metal Chelation
Authors: Lejault Pauline , Duskova Katerina , Bernhard Claire , Valverde Ibai E. , Romieu Anthony , Monchaud David
Published: August 2019

Recent advances in the use of radiometals for both imaging and therapy has spurred on the development of an original chemistry that endows radionuclide‐chelating molecular cages with ever sharper physicochemical properties. Macrocyclic polyamines (MPAs) such as cyclen and DOTA are among the most frequently encountered cages for the design of new radiotracers, owing to their versatile chemistry that makes them customizable molecular tools. The idea of using MPAs for alternative purposes has recently emerged, with an eye towards benefiting from their unique topology, versatility, symmetry and water‐solubility. This review summarizes strategies that have been recently implemented in which MPAs are used as multivalent molecular platforms for constructing sophisticated suprastructures that found applications in various fields, from materials chemistry to chemical biology. These original approaches are invaluable in that they successfully expand the scope of applications of MPAs far beyond their restricted roles of metal chelating appendages.
Production of polycaprolactone nanoparticles with hydrodynamic diameters below 100 nm
Authors: Witt Sandra , Scheper Thomas , Walter Johanna‐Gabriela
Published: August 2019

Cancer is a worldwide increasing burden and its therapy is often challenging and causes severe side effects in healthy tissue. If drugs are loaded into nanoparticles, side effects can be reduced, and efficiency can be increased via the enhanced permeability and retention effect. This effect is based on the fact that nanoparticles with sizes from 10 to 200 nm can accumulate in tumor tissue due to their leaky vasculature. In this work, we produced polycaprolactone (PCL) in the sizes 1.8, 5.4, and 13.6 kDa and were able to produce spherical shaped nanoparticles with mean diameters of 64 ± 19 nm out of the PCL5.4 and 45 ± 8 nm out of the PCL13.6 reproducibly. By encapsulation of paclitaxel the diameter of that nanoparticles did not increase, and we were able to encapsulate 73 ± 7 fmol paclitaxel per 1000 particles in the PCL5.4‐nanoparticles and 35 ± 8 fmol PTX per 1000 PCL13.6‐nanoparticles. Furthermore, we coupled the aptamer S15 to preformed PCL5.4‐nanoparticles resulting in particles with a hydrodynamic diameter of 153 nm. This offers the opportunity to use these nanoparticles for targeted drug delivery.
Locally weighted classifiers for detection of neighbor discovery protocol distributed denial‐of‐service and replayed attacks
Authors: Alsadhan Abeer , Hussain Abir , Liatsis Panos , Alani Mohammed , Tawfik Hissam , Kendrick Phillip , Francis Hulya
Published: August 2019

The Internet of things requires more internet protocol (IP) addresses than IP version 4 (IPv4) can offer. To solve this problem, IP version 6 (IPv6) was developed to expand the availability of address spaces. Moreover, it supports hierarchical address allocation methods, which can facilitate route aggregation, thus limiting expansion of routing tables. An important feature of the IPv6 suites is the neighbor discovery protocol (NDP), which is geared towards substitution of the address resolution protocol in router discovery and function redirection in IPv4. However, NDP is vulnerable to denial‐of‐service (DoS) attacks. In this contribution, we present a novel detection method for distributed DoS (DDoS) attacks, launched using NDP in IPv6. The proposed system uses flow‐based network representation, instead of a packet‐based one. It exploits the advantages of locally weighted learning techniques, with three different machine learning models as its base learners. Simulation studies demonstrate that the intrusion detection method does not suffer from overfitting issues and offers lower computation costs and complexity, while exhibiting high accuracy rates. In summary, the proposed system uses six features, extracted from our bespoke dataset and is capable of detecting DDoS attacks with 99% accuracy and replayed attacks with an accuracy of 91.17%, offering a marked improvement in detection performance over state‐of‐the‐art approaches.
Node selection and utility maximization for mobile edge computing–driven IoT
Authors: Riaz Nida , Qaisar Saad , Ali Mudassar , Naeem Muhammad
Published: August 2019

Optimal user association and resource utilization entails a challenging problem of high latency in mobile edge computing (MEC)–driven Internet of Things (IoT) applications. Increased power consumption is another aspect that requires attention, specifically for the systems that involve huge number of users (IoT nodes) and computing devices (cloudlets/MEC nodes/fog nodes). Though MEC/fog networks are designed for low latency and low transmit power connections, yet the substantial increase in IoT devices signify the need to redesign it for future demands. In this article, we formulate an optimization problem related to quality of service–driven node selection and utility maximization subject to power and workload constraints for applications that require very low latency. Outer approximation algorithm is a proven technique in the field of optimization theory and is scalable with number of nodes. A distributed self‐converging algorithm based on the outer approximation algorithm is presented in this work, which proved to be efficient for the problem formulated. Extensive simulations are done to validate the numerical results. This work concludes by comparing results of outer approximation method with matching theory to validate its effectiveness.
Review on safrole: identity shift of the ‘candy shop’ aroma to a carcinogen and deforester
Authors: Kemprai Phirose , Protim Mahanta Bhaskar , Sut Dristi , Barman Rubi , Banik Dipanwita , Lal Mohan , Proteem Saikia Siddhartha , Haldar Saikat
Published: August 2019

Safrole, a phenylpropene with a ‘candy shop’ aroma, is abundant in nature among diverse plant genera such as Sassafras, Ocotea, Cinnamomum, Myristica, and Piper. Sassafras oil has been used extensively for a long time, first by Native Americans and later by European settlers in traditional medicine and as a flavouring agent. Until 1960 the consumption of safrole by the western population, as a flavouring agent in beer, meat, and soft drinks, was unregulated. Later, the recognition of this phytochemical as a weak hepatocarcinogen with demonstrated genotoxicity in rodents led to strict restrictions on its use in food by various regulatory bodies globally. Moreover, in Asian countries oral carcinogenesis has been linked to safrole through the habit of chewing betel quid. As a separate issue, safrole is an inexpensive synthetic precursor to the illicit recreational drug Ecstasy. Accelerating demand for this party drug during the last few decades has encouraged the unscientific harvesting, illegal production, and trading of safrole‐rich oils, leading to massive deforestation. Recently, many government authorities have enforced laws to restrict the production and harvesting of safrole‐bearing plants. Thus, the identity of safrole has altered with time from a pleasant flavouring agent to a hepatocarcinogen, and more recently as a driver of the destruction of biodiversity. Law enforcement has not only hampered its availability but has also extensively affected industrial use. Our review describes the research progress (1960–2018) on its natural distribution, carcinogenicity, usage as a natural synthon, and the regulations imposed on safrole and safrole‐rich oils worldwide. Finally, we draw our readers’ attention to the sustainable use of this phytochemical for a better future.
The effects of extruded corn flour on rheological properties of wheat‐based composite dough and the bread quality
Authors: Sun Huaxing , Ju Qian , Ma Jie , Chen Jincheng , Li Yaoxi , Yuan Yanqiu , Hu Yayun , Fujita Kaori , Luan Guangzhong
Published: August 2019

The effects of extruded corn flour (ECF) on the rheological properties of the wheat‐based composite dough and quality of the bread were investigated. The RVA results of the composite flour with ECF showed weak thermal viscosity and resistance to starch retrogradation. Mixolab tests revealed that the water absorption capacity increased with the increasing amount of ECF, while dough development time (DT) and dough stability (ST) showed a downward trend, and the composite dough became more resistant to retrogradation. The microstructure of the composite dough showed that the presence of both ECF and unextruded corn flour (UECF) resulted in a more broken gluten matrix. The breads made from the composite flour with ECF had significantly softer texture, lower hardening percentage with storage time, darker crust color, larger specific volume, and higher sensory scores than the UECF ones. It is concluded that the extrusion of corn flour is an effective way to improve the quality of the composite bread and retard staling during storage.
Transcriptional networks in acute myeloid leukemia
Authors: Thoms Julie A. I. , Beck Dominik , Pimanda John E.
Published: August 2019

Acute myeloid leukemia (AML) is a complex disease characterized by a diverse range of recurrent molecular aberrations that occur in many different combinations. Components of transcriptional networks are a common target of these aberrations, leading to network‐wide changes and deployment of novel or developmentally inappropriate transcriptional programs. Genome‐wide techniques are beginning to reveal the full complexity of normal hematopoietic stem cell transcriptional networks and the extent to which they are deregulated in AML, and new understandings of the mechanisms by which AML cells maintain self‐renewal and block differentiation are starting to emerge. The hope is that increased understanding of the network architecture in AML will lead to identification of key oncogenic dependencies that are downstream of multiple network aberrations, and that this knowledge will be translated into new therapies that target these dependencies. Here, we review the current state of knowledge of network perturbation in AML with a focus on major mechanisms of transcription factor dysregulation, including mutation, translocation, and transcriptional dysregulation, and discuss how these perturbations propagate across transcriptional networks. We will also review emerging mechanisms of network disruption, and briefly discuss how increased knowledge of network disruption is already being used to develop new therapies.
Steifigkeit des Salzburger Seetons – Vergleich von Ergebnissen aus Drucksondierungen und Laborversuchen
Authors: Ausweger Georg M. , Havinga Michael , Lüftenegger Roland , Marte Roman , Oberhollenzer Simon
Published: August 2019

Cone penetration tests are a good option for in situ tests in case of soft, fine‐grained soils. Thus, they are often used for subsoil investigations in the Salzburger Becken, which mainly consists of silty, fine‐sandy sediments. Unfortunately, empirical correlations for the determination of soil parameters from cone penetration tests in case of silty, fine‐sandy soils are very rare in literature. This contribution should help to evaluate the known correlations and correlation factors for the determination of soil stiffness based on cone penetration tests regarding their applicability for the Salzburger Seeton. This is done by the comparison of cone penetration test results with results from laboratory tests.
Vergleichende Bewertung der Bodeneigenschaften durch CPT und DMT
Authors: Maček Matej , Logar Janko , Pulko Boštjan
Published: August 2019

The piezocone penetration test (CPT) and flat dilatometer test (DMT) are routinely used in geotechnical practice and are often considered adequate for detailing of soil profile and determination of soil properties. This paper presents comparison of results of ground characterization and evaluation of soil properties based on the combined use of CPT and DMT at four different locations, each with different ground composition. Evaluation of both tests in terms of soil type, undrained shear strength, constrained modulus and friction angle is presented and results are compared. In some cases the results are also compared with laboratory data. The main objective is to show that companion sets of CPT and DMT at a given site could be used to better define the geotechnical ground model and to increase confidence in the evaluation of soil properties.