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This study aims to treat the development and application of sequence characterised amplified region (SCAR) markers for the detection of plant based adulterants (dried red beet pulp and powdered Ziziphus nummularia fruits) in traded ground chilli.

Adulterant‐specific DNA fragments (red beet pulp specific – “Beet 01” and Z. nummularia specific – “Ziz 01”) identified by random amplified polymorphic DNA polymerase chain reaction (RAPD‐PCR) analysis were cloned and sequenced for SCAR marker development. Red beet pulp specific SCAR primer pair, B1, and Z. nummularia specific SCAR primer pair, Z1, were designed from the corresponding RAPD marker sequences to amplify SCAR markers of 320 bp and 389 bp, respectively. The utility of the SCAR markers for adulterant detection was verified in model blends of chilli powder with the adulterants. Six commercial samples of ground chilli powder were analysed using the SCAR markers.

SCAR markers could detect the adulterants at a concentration as low as 10 g adulterant kg⁻¹ of blended sample. The Z. nummularia SCAR marker could detect the presence of Z. nummularia fruit adulteration in one of the commercial samples. All the market samples tested were free from red beet pulp adulteration.

The PCR‐based method developed in the study is simple, rapid, and sensitive and has the potential to be developed into a quantitative analytical method and for commercial PCR kits for the large‐scale screening of ground chilli to detect and prevent plant‐based adulterants. The work has public health significance too, as ground chilli is one of the major spices consumed worldwide.

The study is the first report on the development of SCAR markers for adulterant detection in ground chilli. This work has relevance, as adulteration is a major concern of the sanitary and phytosanitary issues of the World Trade Organization (WTO) agreement.

This paper aims to explore the experience of living with scars from self-injury; how people who self-injure (SI) make meaning of their scars and how these scars are a part of the identity construction process.

It is observed that 60 entries, from 25 online narrative blogs detailing the experience of living with self-injury scars, were analyzed using a contextualized thematic analysis informed by an embodied perspective.

The analysis generated two dominant themes: temporal aspects of identity; and social stigma and scars.

Far-reaching consequences of self-injury scars on the daily lives of people who SI was found. This included a person’s posture, clothing, choices of career, inclusion in family life, leisure activities and relationships; all of which have corollaries in emotional and psychological well-being. Scars were found to be self-narrative with particular salience given to how scars represented healing. Novel findings included the central role scars played in the resistance of self-injury stigma.

Assess and compare scarring effects of unemployment in Germany to other countries and to consider firm heterogeneity.

The author uses linked employer-employee data to analyze the effect of unemployment and its duration on future wages in Germany. Using administrative data on workers and firms in Germany and considering registered and unregistered unemployment episodes, the results show long-lasting wage losses caused by unemployment incidences. Furthermore, the estimations indicate that unemployment duration as well as selectivity into firms paying lower wages is of particular relevance for the explanation of wage penalties of re-employed workers.

Unemployment causes massive and persistent wage declines in the future, which depend on the unemployment duration. Furthermore, reduced options of unemployed workers and selectivity in firms contribute to a large part of unemployment scarring.

Findings are relevant for current debates on unemployment and can help design measures to avoid huge costs of unemployment.

This paper analyses long-term unemployment scarring by considering not only unemployment duration but also selectivity in firms and its effect on the scarring effect.

This paper aims to present an analysis of several 3 D texture parameters for the entire wear scars obtained in severe regime, on a four-ball tester. The aim of this analysis is to correlate the tribological parameter as wear scar diameter to texture parameters.

Tested lubricants were rapeseed oil, rapeseed oil additivated with 1% Wt nano TiO₂ and rapeseed oil additivated with 1%Wt nano ZnO. The severe regime was applied for 1400 rpm and for loads increasing in steps of 50 N, from 500 to 900 N. Several analyzed roughness parameters (height parameters and functional ones) could be related to the evolution of a wear parameter, the wear scar diameter. Comparing the values for neat rapeseed oil and additivated variants, the texture parameters allow for evaluating if the additives protect or not the worn surfaces.

Measurements pointed out two groups of roughness parameters: one that has an evolution depending on wear scar diameter (WSD) and load (Sa, St, functional parameters) and one including Ssk that has shown no dependence on load and WSD. Also, the functional parameters Spk and Svk follow in a similar manner the wear parameter, WSD, but Sk is the least dependent on load. For the highest load, amplitude parameters such as Sa and St are following the tendency of WSD. Each lubricant has its particular correlation between wear parameters and texture quality, expressed by the help of a set of roughness parameters.

Such studies help tribologists to rank lubricants based on a combined analysis with wear parameters and texture parameters.

The results allow for evaluating new formulated lubricants.

The study on the quality on worn surfaces introduces the original idea of analyzing the entire wear scar surface (approximated by an ellipse with the axes as those experimentally measured) by the help of a set of 3 D roughness parameters.

This paper aims to study the micro-structure evolution of friction layers to optimize the friction and wear behaviors of TiAl-based material. It further enlarges the scope of using TiAl alloys and increase in the service life of TiAl alloy-made mechanical components, especially under some extreme conditions.

To study the structure evolution of friction layers, the HT-1000 tribometer is used to study the friction and wear properties of as-prepared samples. With the assistance of field emission scanning electron microscopy and an electron probe micro-analyzer, the stratified structures in cross-sections and a surface morphology of the wear scars are well characterized. A ST400 surface profiler helps in better understanding of the three-dimensional texture profiles of wear scars. X-ray diffractometer (XRD) is also used to analyze phases in the as-prepared samples.

An analysis method on the micro-structure evolution can provide better views to understand the influence of friction layers on the tribological behavior, at different wear stages. It finds that the micro-structure evolution of friction layers has an immediate effect on the friction coefficients and wear rates of TiAl-based material. It also proves to be a useful tool for evaluating the behaviors in friction and wear of TiAl-based material.

The findings of this paper provide better assistance to explore the effect of friction layers on the friction and wear behaviors of TiAl-based materials. The results help in deep understanding of the micro-structure evolution of friction layers. It also increases the service life of TiAl-based mechanical components.

The aim of this paper is to research grease and additives' influence on fretting wear of mild steel.

Experiments were performed on a laboratory stand with contact conditions cylinder on flat. The mild steel couples were tested under dry conditions and lubricated with mineral and synthetic greases containing as additives: graphite, molybdenum disulphide, ZDDP and molybdenum dithiocarbamate in different concentrations.

The results revealed a significant influence of grease consistency and its welding load on the fretting wear of steel couples. Graphite and molybdenum disulphide were effective in a 10 percent concentration. ZDDP additive in a more than 1 percent concentration increased fretting wear. Molybdenum dithiocarbamate was not more effective than molybdenum disulphide powder. Grease lubrication of the fretted couple changed significantly the wear mechanism observed on SEM photographs of fretting scars.

The paper presents some indications of proper selection of grease for fretting prevention.

The influence of the main features of grease on fretting wear was confirmed on the basis of extensive investigation.

It is increasingly important to study labour market outcomes for people who are not in employment, education, or training (NEET). Where most studies focus solely on young people, the purpose of this paper is to include both younger and older NEETs to find out if there is any long-term scarring effect, and if the effect is different between these two groups.

This study uses a twin-based estimation method for the first time to measure the long-term effect of economic inactivity on income. The analysis is based on biological twins, in order to control for individuals’ unobservable heterogeneity. It is assumed that twins are similar to each other and the only unobservable heterogeneity is at the family level. Register-based data from Statistics Sweden is used.

The result indicates a significant negative income effect for those who have been in NEET, and is larger for those who have been in NEET for several consecutive periods of time. Individuals who were in NEET during 2001-2003 had on average 62 per cent lower income compared with their twin in 2011. The corresponding number for individuals who were in NEET for just one period was 33 per cent. Hence, time in NEET reduces income. The results show that the long-term scarring effect is not affected by age.

This study utilises for the first time a twin-based estimation method to measure the long-term effect of inactivity. Most studies focus solely on young people, but the authors also include an older group of people.

Periodic economic instabilities and structural changes in the labour market have given rise to a variety of forms of job insecurity. This article compares the scarring effects of different forms of job insecurity on future employment chances, and how they vary across education groups.

Using a sample of real vacancies and data collected in a vignette experiment with employers in Switzerland, a country with a strongly developed vocational education and training (VET) system, this article investigates how employers evaluate a period of unemployment, job hopping and work experience in deskilling jobs when hiring candidates.

The findings reveal that work in deskilling jobs is by far more scarring than unemployment or job hopping. The study also demonstrates that applicants with upper secondary vocational education are impacted the greatest by all three forms of job insecurity.

The study makes use of real vacancies. While experiments have the strength of high internal validity, most experimental studies in recruitment research rely on students as respondents. As this study works with real employers hiring for positions it benefits from high external validity.

The purpose of this study is to investigate the microstructure of fretting wear behavior in 6061-T6 aluminum alloy. The fretting wear of blind riveted lap joints of 6061-T6 aluminum alloy plates, which are widely used in aircraft construction, was investigated. Fretting damages were investigated between the contact surface of the plates and between the plate and the rivet contact surface.

Experiments were carried out using a computer controlled Instron testing machine with 200 kN static and 100 kN dynamic load capacity. Max package computer program was used for the control of the experiments. Fretting scars, width of wear scars, microstructure was investigated by metallographic techniques and scanning electron microscopy.

It was found that fretting damages were occurred between the plates contacting surface and between the plate and rivet contact surface. As load and cycles increased, fretting scars increased. Fretting wear initially begins with metal-to-metal contact. Then, the formed metallic wear particles are hardened by oxidation. These hard particles spread between surfaces, causing three-body fretting wear. Fretting wear surface width increases with increasing load and number of cycles.

The useful life of many tribological joints is limited by wear or deterioration of the fretting components due to fretting by oscillating relative displacements of the friction surfaces. Such displacements are caused by vibrations, reciprocating motion, periodic bending or twisting of the mating component, etc. Fretting also tangibly reduces the surface layer quality and produces increased surface roughness, micropits, subsurface microphone.