Synthesis method comparison of compositionally complex rare earth-based Ruddlesden–Popper n = 1 T′-type cuprates

The multicomponent approach has been successfully expanded to the Ruddlesden–Popper structure with the synthesis of two different high-entropy cuprate compositions: (La_0.2Nd_0.2Gd_0.2Tb_0.2Dy_0.2)₂CuO₄ and (La_0.2Pr_0.2Nd_0.2Sm_0.2Eu_0.2)₂CuO₄. The effect of synthesis method is explored using both solid-state reaction and polymeric steric entrapment (PSE) methods. It is found that PSE leads to more randomly distributed cation species, providing an advantageous method of synthesis for the growing field of high entropy oxides. In situ high-temperature x-ray diffraction tracks the amorphous to crystalline phase transformation in (La_0.2Nd_0.2Gd_0.2Tb_0.2Dy_0.2)₂CuO₄ powder, synthesized using the PSE method. Using the High-Temperature XRD data, a method for gaining information on the kinetic behavior is also applied. Magnetometry of both compositions indicates ferrimagnetic behavior at low temperatures.     

Remotely sensed surface water extent as an indicator of short-term changes in ecohydrological processes in sub-Saharan Western Africa

The highly variable rainfall in the arid and semi-arid regions of sub-Saharan Western Africa drives both surface water availability and vegetation cover. Recent studies have established linkages between rainfall and vegetation cover at local to regional scales, but no study related yet remote sensing derived rainfall and vegetation cover to the available surface water. A new dataset based on SPOT VEGETATION (VGT) represents surface water bodies (SWB) in the arid and semi-arid regions of sub-Saharan Western Africa. Water bodies represent the integrated hydrological response of a catchment, and changes in their spatial extent involve complex interactions at the catchment scale. We analyzed time series of remotely sensed vegetation cover, rainfall and surface water extent for the period 1999–2008, and could detect and statistically demonstrate the links between these biophysical variables. Our findings for two regions in Mali and Burkina Faso suggest that vegetation cover is positively related to the amount of available surface water for those catchments that are mainly covered by annual plants. The observed relationships between remotely sensed variables allow developing ecological indicators that can indicate short-term changes in arid and semi-arid ecosystems at local to regional scales.     

Staining of white marble

White marbles have been a popular building material since Greek and Roman times. Recently, the long-term aesthetical aspect of white marbles has been questioned. In this paper, the results of our research on the development of stains on different types of white marbles (seven Italian and one Greek marble) are presented. The staining of white marbles has been studied by using different microscopic techniques and staining methods. In addition, a new optimised staining technique is proposed for artificially staining of white Carrara marble. An objective normalised measuring method is also developed for quantifying the discolouration of natural materials. Although the inclusions of organic material in crystals in marbles are often suggested to be responsible for staining, this investigation illustrated that they have little or no influence on the discolouration of the natural stones. Systematic investigation showed that the presence of pyrite and hematite crystals plays a dominant role for the development of discolouration.     

Effect of transfer on droplet size in liquid-liquid dispersions

Mean droplet diameter of the dispersed phase in pulsed plate extraction columns was measured for binary and ternary systems. A change in the droplet size in the presence of solute, dependent on such factors as the direction of mass transfer, droplet size in the binary system, radio of diffusion coefficients, viscosity of the continuous phase, interfacial tension and driving force for extraction was observed. Two new empirical correlations of mean droplet sizes in mass transfer conditions are proposed. These correlations have been successfully applied to other extraction columns.     

Eye-tracking Analysis in Landscape Perception Research: Influence of Photograph Properties and Landscape Characteristics

Abstract

The European Landscape Convention emphasises the need for public participation in landscape planning and management. This demands understanding of how people perceive and observe landscapes. This can objectively be measured using eye tracking, a system recording eye movements and fixations while observing images. In this study, 23 participants were asked to observe 90 landscape photographs, representing 18 landscape character types in Flanders (Belgium) differing in degree of openness and heterogeneity. For each landscape, five types of photographs were shown, varying in view angle. This experiment design allowed testing the effect of the landscape characteristics and photograph types on the observation pattern, measured by Eye-tracking Metrics (ETM). The results show that panoramic and detail photographs are observed differently than the other types. The degree of openness and heterogeneity also seems to exert a significant influence on the observation of the landscape.     

On the Relation between Morphology and FET Mobility of Poly(3‐alkylthiophene)s at the Polymer/SiO2 and Polymer/Air Interface

The influence of the interface of the dielectric SiO₂ on the performance of bottom‐contact, bottom‐gate poly(3‐alkylthiophene) (P3AT) field‐effect transistors (FETs) is investigated. In particular, the operation of transistors where the active polythiophene layer is directly spin‐coated from chlorobenzene (CB) onto the bare SiO₂ dielectric is compared to those where the active layer is first spin‐coated then laminated via a wet transfer process such that the film/air interface of this film contacts the SiO₂ surface. While an apparent alkyl side‐chain length dependent mobility is observed for films directly spin‐coated onto the SiO₂ dielectric (with mobilities of ≈10^?3 cm² V^?1 s^?1 or less) for laminated films mobilities of 0.14 ± 0.03 cm² V^?1 s^?1 independent of alkyl chain length are recorded. Surface‐sensitive near edge X‐ray absorption fine structure (NEXAFS) spectroscopy measurements indicate a strong out‐of‐plane orientation of the polymer backbone at the original air/film interface while much lower average tilt angles of the polymer backbone are observed at the SiO₂/film interface. A comparison with NEXAFS on crystalline P3AT nanofibers, as well as molecular mechanics and electronic structure calculations on ideal P3AT crystals suggest a close to crystalline polymer organization at the P3AT/air interface of films from CB. These results emphasize the negative influence of wrongly oriented polymer on charge carrier mobility and highlight the potential of the polymer/air interface in achieving excellent “out‐of‐plane” orientation and high FET mobilities.     

Clinical evaluation and psychological aspects of temporomandibular joint disorders]

Establishing the patient's clinical diagnosis depends on gathering as much information of the patient and his or her signs and symptoms as possible. This information can be gathered from history, physical and psychological examination, diagnostic analysis. It is also important to look upon pain as a disorder and to consider the relationship between pain and psychological factors. The differential diagnosis is constructed through a biopsychological model of illness rather than through a more traditional biomedical model of disease. To arrive at a consistently accurate clinical diagnosis in patients with TMJ and craniofacial pain, the technique of clinical diagnosis must be well defined, reliable and include examination of the head and the neck, cranial nerves and the stomatognathic system. The craniomandibular index provides a standardized examination of the stomatognathic system that has been tested on validity and reliability. This chapter focuses on the techniques of history taking clinical and psychological examination and diagnostic criteria for temporomandibular joint disorders and muscle pain.     

Indecisiveness and high school students' career decision-making process: Longitudinal associations and the mediational role of anxiety.

This study examined how indecisiveness relates to adolescents' process of choosing a study in higher education, using a longitudinal design. A sample of 281 students participated at the beginning, middle, and end of Grade 12. Findings show that indecisiveness was a risk factor for future levels of coping with the career decisional tasks of broad and in-depth environmental exploration (amount of information and exploratory behavior), amount of self-information, decisional status, and commitment. However, indecisiveness did not relate to the degree of change in decisional tasks during Grade 12. Moreover, results suggest that the linkage of indecisiveness with the amount of in-depth environmental information, the amount of self-information, decisional status, and commitment was mediated by adolescents' career choice anxiety. Finally, stability data provided support for the conceptualization of indecisiveness as a trait. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Influence of material handling devices on the physical load during the end assembly of cars

The effect of using a mechanical device on physical load was analysed during the end assembly of cars. Five tasks, further sub-divided into lifting and positioning, were performed by someone experienced in working with and without the mechanical tool. A practical methodology was used: the subjective walk and talk through method, the NIOSH equation (1991), a three-dimensional goniometer (Back Tracker) and surface electromyography (EMG) of the relevant muscle groups. According to the NIOSH equation, 8 out of 10 of the tasks should only be performed by trained workers and preferably with tools. The Back Tracker revealed that the mechanical tools reduced posture angles significantly (p0.05) for installing the windows, but not for left lateroflexion during pre-assembly of windows. It was clear from the EMG analysis that using tools did not always decrease muscular activity significantly. In general, the appropriateness of each tool needs to be evaluated separately taking the subjective criteria into account.

Relevance to industry

In this study, the relevance of using a mechanical device to reduce the physical load during car assembly, is evaluated. As the tools are expensive, it is important to the industry whether they are being used and how efficient they are.     

Road to Metastasis: The TWEAK Pathway as a Discriminant between Metastasizing and Non-Metastasizing Thick Melanomas

Cutaneous melanoma (CM) is the most aggressive form of skin cancer, and its worldwide incidence is rapidly increasing. Early stages can be successfully treated by surgery, but once metastasis has occurred, the prognosis is poor. However, some 5–10% of thick (≥2 mm) melanomas do not follow this scenario and run an unpredictable course. Little is known about the factors that contribute to metastasis in some patient with thick melanomas and the lack thereof in thick melanoma patients who never develop metastatic disease. We were therefore interested to study differential gene expression and pathway analysis and compare non-metastatic and metastatic thick melanomas. We found that the TNF-like weak inducer of apoptosis (TWEAK) pathway was upregulated in thick non-metastasizing melanomas. MAP3K14 (NIK1), BIRC2 (cIAP1), RIPK1, CASP7, CASP8, and TNF play an important role in inhibiting proliferation and invasion of tumor cells via the activation of the non-canonical NF-κB signaling pathway. In particular, this pathway sensitizes melanoma cells to TNF-alpha and activates the apoptosis module of the TWEAK pathway in thick non-metastasizing melanomas. Hence, our study suggests a potential role of the TWEAK pathway in inhibiting thick melanoma from metastasis. Exploitation of these genes and the pathway they control may open future therapeutic avenues.