Reconciling measurement and modelling studies of the sources and fate of perfluorinated carboxylates

Environmental contextFive years ago a well-cited review of the sources and fate of perfluorinated carboxylates was published. The findings of that review are revisited here in light of recently published measurement and modelling studies of the sources and fate of these compounds, and an attempt is made to reconcile the many seemingly disparate findings reported. This review also aims to provide a road map for future research on the sources and fate of perfluorinated carboxylates and related compounds. AbstractThis study critically evaluates the recently published measurement and modelling studies of the sources and fate of perfluorinated carboxylates (PFCAs). It is concluded that modelling studies provide support to the ‘direct hypothesis’ for PFOA and PFNA (i.e. the global dominance of direct sources (mainly from fluoropolymer manufacturing)). Empirical evidence for the importance of direct sources of PFOA and PFNA is provided by PFNA : PFOA ratios and isomer profiles of PFOA in ocean water. However, homologue patterns of long-chain PFCAs in biota from remote regions suggest that indirect sources (mainly from precursor degradation) are proportionally more important for PFCAs with more than 10 carbons. Temporal data in biotic and abiotic media are reviewed and an increasing trend to 2000 is observed for all PFCAs, with discrepancies in time trends reported after that period. Some studies on temporal patterns report a levelling off or decline in the latter part of the 2000s for PFOA and PFNA, whereas others show a continual increase throughout the study period. Differences in temporal patterns result from the fact that some environments respond faster to emission changes than others and may thus be useful to elucidate the importance of direct and indirect sources to different regions.

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Three-Dimensional Thematic Map Imaging of the Yacht Port on the Example of the Polish National Sailing Centre Marina in Gdańsk

Applied Sciences ◽

10.3390/app11157016 ◽

2021 ◽

Vol 11 (15) ◽

pp. 7016

Author(s):

Pawel S. Dabrowski ◽

Cezary Specht ◽

Mariusz Specht ◽

Artur Makar

Keyword(s):

Spatial Data ◽

Convex Surface ◽

Dimensional Space ◽

Three Dimensional ◽

Future Research ◽

Two Dimensional ◽

Thematic Maps ◽

Research Directions ◽

Future Research Directions ◽

The Many

The theory of cartographic projections is a tool which can present the convex surface of the Earth on the plane. Of the many types of maps, thematic maps perform an important function due to the wide possibilities of adapting their content to current needs. The limitation of classic maps is their two-dimensional nature. In the era of rapidly growing methods of mass acquisition of spatial data, the use of flat images is often not enough to reveal the level of complexity of certain objects. In this case, it is necessary to use visualization in three-dimensional space. The motivation to conduct the study was the use of cartographic projections methods, spatial transformations, and the possibilities offered by thematic maps to create thematic three-dimensional map imaging (T3DMI). The authors presented a practical verification of the adopted methodology to create a T3DMI visualization of the marina of the National Sailing Centre of the Gdańsk University of Physical Education and Sport (Poland). The profiled characteristics of the object were used to emphasize the key elements of its function. The results confirmed the increase in the interpretative capabilities of the T3DMI method, relative to classic two-dimensional maps. Additionally, the study suggested future research directions of the presented solution.

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Thermoplastic Pultrusion: A Review

Polymers ◽

10.3390/polym13020180 ◽

2021 ◽

Vol 13 (2) ◽

pp. 180

Author(s):

Kirill Minchenkov ◽

Alexander Vedernikov ◽

Alexander Safonov ◽

Iskander Akhatov

Keyword(s):

Composite Structures ◽

Raw Materials ◽

Thermoplastic Composites ◽

Future Research ◽

Transportation Industry ◽

Architectural Engineering ◽

Simulation Techniques ◽

New Perspective ◽

The Many ◽

Lower Production

Pultrusion is one of the most efficient methods of producing polymer composite structures with a constant cross-section. Pultruded profiles are widely used in bridge construction, transportation industry, energy sector, and civil and architectural engineering. However, in spite of the many advantages thermoplastic composites have over the thermoset ones, the thermoplastic pultrusion market demonstrates significantly lower production volumes as compared to those of the thermoset one. Examining the thermoplastic pultrusion processes, raw materials, mechanical properties of thermoplastic composites, process simulation techniques, patents, and applications of thermoplastic pultrusion, this overview aims to analyze the existing gap between thermoset and thermoplastic pultrusions in order to promote the development of the latter one. Therefore, observing thermoplastic pultrusion from a new perspective, we intend to identify current shortcomings and issues, and to propose future research and application directions.

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Designing of Nanomaterials-Based Enzymatic Biosensors: Synthesis, Properties, and Applications

Electrochem ◽

10.3390/electrochem2010012 ◽

2021 ◽

Vol 2 (1) ◽

pp. 149-184

Author(s):

Francisco T. T. Cavalcante ◽

Italo R. R. de A. Falcão ◽

José E. da S. Souza ◽

Thales G. Rocha ◽

Isamayra G. de Sousa ◽

...

Keyword(s):

Enzyme Immobilization ◽

State Of The Art ◽

Volume Ratio ◽

The State ◽

Future Research ◽

Synthesis Properties ◽

Signal Response ◽

Enzymatic Biosensors ◽

The Many ◽

Biological Entities

Among the many biological entities employed in the development of biosensors, enzymes have attracted the most attention. Nanotechnology has been fostering excellent prospects in the development of enzymatic biosensors, since enzyme immobilization onto conductive nanostructures can improve characteristics that are crucial in biosensor transduction, such as surface-to-volume ratio, signal response, selectivity, sensitivity, conductivity, and biocatalytic activity, among others. These and other advantages of nanomaterial-based enzymatic biosensors are discussed in this work via the compilation of several reports on their applications in different industrial segments. To provide detailed insights into the state of the art of this technology, all the relevant concepts around the topic are discussed, including the properties of enzymes, the mechanisms involved in their immobilization, and the application of different enzyme-derived biosensors and nanomaterials. Finally, there is a discussion around the pressing challenges in this technology, which will be useful for guiding the development of future research in the area.

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The many faces of suzhi in the Chinese organization and society

Journal of Chinese Human Resource Management ◽

10.1108/jchrm-01-2014-0004 ◽

2014 ◽

Vol 5 (1) ◽

pp. 51-61 ◽

Cited By ~ 2

Author(s):

Sean Upton-McLaughlin

Keyword(s):

Chinese Culture ◽

Mainland China ◽

Future Research ◽

Chinese Society ◽

Content Type ◽

Mainland Chinese ◽

Foreign Companies ◽

Expatriate Managers ◽

The Many ◽

Practical Implications

Purpose – The purpose of this paper was to explore the Chinese concept of suzhi and how it relates to behavioral standards within mainland Chinese society and the workplace. The article provides a general discussion of suzhi and its inherent elements to act as a foundation for the education of expatriate managers and executives and for future research by Chinese human resource management (HRM) scholars. Design/methodology/approach – This paper draws on the author's first-hand experience and observations from five years of living and working abroad in mainland China with Chinese companies and executives. Findings – The concept of suzhi in China is a reflection of multiple behavioral standards throughout China. And while suzhi's roots are in ancient Chinese culture and Confucianism, it is also subject to influence and change. Practical implications – The paper may serve as a foundation both for expatriate managers seeking to improve HRM practices in foreign companies in China and future scholars who wish to conduct further research on suzhi and Chinese behavioral standards as they can be applied to the workplace. Originality/value – This is an attempt to enlighten expatriate managers and executives in China on the concept of suzhi and its implication for HRM in China.

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Social Norms Sustaining Intimate Partner Violence: A Systematic Review of Methodologies for Proxy Measures

Trauma Violence & Abuse ◽

10.1177/15248380211013141 ◽

2021 ◽

pp. 152483802110131

Author(s):

Ilana Seff

Keyword(s):

Systematic Review ◽

Intimate Partner Violence ◽

Social Norms ◽

Partner Violence ◽

Evidence Base ◽

Intimate Partner ◽

Future Research ◽

Data Sets ◽

Boolean Search ◽

The Many

In light of the many robust quantitative data sets that include information on attitudes and behaviors related to intimate partner violence (IPV), and in an effort to expand the evidence base around social norms and IPV, many researchers construct proxy measures of norms within and across groups embedded in the data. While this strategy has become increasingly popular, there is no standardized approach for assessing and constructing these norm proxies, and no review of these approaches has been undertaken to date. This study presents the results of a systematic review of methods used to construct quantitative proxy measures for social norms related to IPV. PubMed, Embase, Popline, and Scopus, and PsycINFO were searched using Boolean search techniques. Inclusion criteria comprised studies published since 2000 in English that either (i) examined a norm proxy related to gender or IPV or (ii) analyzed the relationship between a norm proxy and perpetration of, experiences of, or attitudes toward IPV. Studies that employed qualitative methods or that elicited direct measures of descriptive or injunctive norms were not included. Twenty-six studies were eligible for review. Evidence from this review highlights inconsistencies in how proxies are constructed, how they are assessed to ensure valid representation of norms, and how researchers acknowledge their respective method’s limitations. Key processes and reflections employed by some of the studies are identified and recommended for future research inquiries.

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Are We Loving Our National Parks to Death? A Call for Research on Crime and Law Enforcement in the U.S. National Park System

Criminal Justice Review ◽

10.1177/07340168211015726 ◽

2021 ◽

pp. 073401682110157

Author(s):

William Andrew Stadler ◽

Cheryl Lero Jonson ◽

Brooke Miller Gialopsos

Keyword(s):

Law Enforcement ◽

National Parks ◽

National Park ◽

Future Research ◽

Road Map ◽

Current State ◽

Park Service ◽

Service Data ◽

National Park System ◽

The U.S

Despite a recent surge of visitation and frequent media accounts of lawlessness in America’s national parks, little empirical research has been dedicated to crime and law enforcement in the U.S. national park system. The absence of systematic crime and justice research within these protected spaces should raise concern, as recent park service data and intra-agency reports suggest visitor growth, funding and personnel declines, operational shortcomings, and technology constraints may endanger the capacity of the National Park Service (NPS) to adequately address anticipated crime threats in the 21st century. This call for research aims to raise awareness of the contemporary law enforcement challenges facing this federal agency and encourage the study of crime and justice issues within the U.S. national park system. We briefly examine the evolution and current state of NPS law enforcement and its associated challenges and conclude with a conceptual road map for future research occurring in these protected spaces.

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Control of flexible manipulators: A survey

Robotica ◽

10.1017/s0263574703005642 ◽

2004 ◽

Vol 22 (5) ◽

pp. 533-545 ◽

Cited By ~ 237

Author(s):

M. Benosman ◽

G. Le Vey

Keyword(s):

Linear Models ◽

Control Strategies ◽

Research Area ◽

Future Research ◽

Complex Nature ◽

Open Problems ◽

Complex Models ◽

The Many ◽

The One ◽

Flexible Arms

A survey of the field of control for flexible multi-link robots is presented. This research area has drawn great attention during the last two decades, and seems to be somewhat less “attractive” now, due to the many satisfactory results already obtained, but also because of the complex nature of the remaining open problems. Thus it seems that the time has come to try to deliver a sort of “state of the art” on this subject, although an exhaustive one is out of scope here, because of the great amount of publications. Instead, we survey the most salient progresses – in our opinion – approximately during the last decade, that are representative of the essential different ideas in the field. We proceed along with the exposition of material coming from about 119 included references. We do not pretend to deeply present each of the methods quoted hereafter; however, our goal is to briefly introduce most of the existing methods and to refer the interested reader to more detailed presentations for each scheme. To begin with, a now well-established classification of the flexible arms control goals is given. It is followed by a presentation of different control strategies, indicating in each case whether the approach deals with the one-link case, which can be successfully treated via linear models, or with the multi-link case which necessitates nonlinear, more complex, models. Some possible issues for future research are given in conclusion.

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A general Cluster data and global MHD simulation comparison

Annales Geophysicae ◽

10.5194/angeo-26-3411-2008 ◽

2008 ◽

Vol 26 (11) ◽

pp. 3411-3428 ◽

Cited By ~ 3

Author(s):

P. Daum ◽

M. H. Denton ◽

J. A. Wild ◽

M. G. G. T. Taylor ◽

J. Šafránková ◽

...

Keyword(s):

Large Scale ◽

Numerical Models ◽

Mhd Simulation ◽

Global Context ◽

Cluster Data ◽

Verification Methods ◽

Modelling Studies ◽

Global Mhd Simulation ◽

The Many

Abstract. Among the many challenges facing the space weather modelling community today, is the need for validation and verification methods of the numerical models available describing the complex nonlinear Sun-Earth system. Magnetohydrodynamic (MHD) models represent the latest numerical models of this environment and have the unique ability to span the enormous distances present in the magnetosphere, from several hundred kilometres to several thousand kilometres above the Earth's surface. This makes it especially difficult to develop verification and validation methods which posses the same range spans as the models. In this paper we present a first general large-scale comparison between four years (2001–2004) worth of in situ Cluster plasma observations and the corresponding simulated predictions from the coupled Block-Adaptive-Tree-Solarwind-Roe-Upwind-Scheme (BATS-R-US) MHD code. The comparison between the in situ measurements and the model predictions reveals that by systematically constraining the MHD model inflow boundary conditions a good correlation between the in situ observations and the modeled data can be found. These results have an implication for modelling studies addressing also smaller scale features of the magnetosphere. The global MHD simulation can therefore be used to place localised satellite and/or ground-based observations into a global context and fill the gaps left by measurements.

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