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The YK 1 shipwreck, found at Yenikapı, Istanbul, is one of 37 shipwrecks dating to the medieval era. This paper describes the studies and the processes which were conducted to conserve the YK 1. Firstly, the level of physical and chemical degradation of the wood from the YK 1 was examined, which revealed that the wood was highly degraded. Therefore, PEG 2000 was chosen for the impregnation process before vacuum freeze-drying. In addition, the ASE values confirmed that the PEG 2000 impregnation and vacuum freeze-drying method together were successful in conserving the YK 1, with values higher than PEG 2000 impregnation and vacuum freeze-drying methods alone. The concentration of the PEG solution in the tank was monitored throughout the impregnation process. Following this, samples taken from the wood cores were analysed using FTIR to evaluate the effectiveness of the impregnation process. Finally, SEM was used to examine the effectiveness of the PEG 2000 impregnation and vacuum freeze-drying method. The SEM images showed that the PEG 2000 was uniformly distributed, and the wood had no deformation after freeze-drying. [ABSTRACT FROM AUTHOR]

The Yenikapı (YK) 12 shipwreck is 1 of 37 shipwrecks found at Yenikapı, Istanbul. This merchantman has been dated to AD 672–876 by radiocarbon analyses. The conservation of YK 12, which was assembled with iron nails, was completed with the pre-impregnation of polyethylene glycol (PEG) and using vacuum freeze-drying processes. However, after conservation, dust formation was observed on some wooden parts of the shipwreck during storage. In this study, iron–sulfur-related problems detected in the woods of YK 12 were evaluated. We analysed samples taken from YK 12 to study the sulfur and iron content in woods from oak (Quercus), walnut (Juglans), and hornbeam (Carpinus), representing taxa with different wood properties. Fourier-transform infrared spectroscopy (FTIR) analyses, X-ray diffraction (XRD), and pH measurements were conducted on five samples. The results of these studies showed that the dust consisted of wood particles, PEG, and hydrated iron sulfates, such as FeSO4·4H2O and FeSO4·7H2O. Additionally, one sample included SiO2, whilst another exhibited a low pH value. These findings highlight the importance of optimum ambient conditions for the storage and display of these shipwrecks in order to prevent the irreversible degradation of YK 12 and other recovered shipwrecks. [ABSTRACT FROM AUTHOR]

As a fabric surface defect, pilling gives clothes an unpleasant appearance and is often characterized with small, complex clusters of fibers attaching to the surface of the garment caused by the fiber migration from yarns to the fabric surface as the fabric rubs against itself, another fabric, or even the skin. In this study, a Markov chain model was built based on the pilling propensity of wool fabrics, evaluated with a scale ranging from 1 (severe pilling) to 5 (non-pilling). These degrees were defined as the state space of Markov chain. The numerical values of the transition probability matrix related to the pilling degrees were obtained by maximum likelihood estimation (MLE). Based on the matrix, it was intended to model the changes in the pilling process of woven wool fabrics. Furthermore, given that the fabric will eventually be in state 1, 2 or 3, accepted as unpleasant appearance; the conditional mean first passage times for any transient state to enter any recurrent state for the first time were determined. [ABSTRACT FROM AUTHOR]

The present study combined dimensional and categorical approaches to emotion to develop normative ratings for a large set of Turkish words on two major dimensions of emotion: arousal and valence, as well as on five basic emotion categories of happiness, sadness, anger, fear, and disgust. A set of 2031 Turkish words obtained by translating Affective Norms for English Words to Turkish and pooling from the Turkish Word Norms were rated by a large sample of 1527 participants. This is the first comprehensive and standardized word set in Turkish offering discrete emotional ratings in addition to dimensional ratings along with concreteness judgments. Consistent with Affective Norms for English Words and word databases in several other languages, arousal increased as valence became more positive or more negative. As expected, negative emotions (anger, sadness, fear, and disgust) were positively correlated with each other, whereas the positive emotion, happiness, was negatively correlated with the negative emotion categories. Data further showed that the valence dimension was strongly correlated with happiness, and the arousal dimension was mostly correlated with fear. These findings show highly similar and consistent patterns with word sets provided in other languages in terms of the relationships between arousal and valence dimensions, relationships between dimensions and specific emotion categories, relationships among specific emotions, and further support the stability of the relationship between basic discrete emotions at the word level across different cultures. [ABSTRACT FROM AUTHOR]

Retrieval results in both costs and benefits to episodic memory. Output interference (OI) refers to the finding that episodic memory accuracy decreases with increasing test trials. Release from OI is the restoration of original accuracy at some point during the test. For example, a release from OI in recognition memory testing occurs when the semantic similarity between stimuli decreases midway through testing, suggesting that item representations stored on early trials cause interference on tests occurring on later trials to the extent that the earlier items share features with the latter items. In two recognition memory experiments, we demonstrate release from OI for words and faces. We also test whether release from OI is the result of interference or is due to a boost in attention caused by reorienting to a novel stimulus type. A test for the foils presented during the initial test list supports the interference account of OI. Implications for models of memory are discussed. [ABSTRACT FROM AUTHOR]

Performance in episodic memory is determined both by accurate retrieval from memory and by decision processes. A substantial body of literature suggests slightly poorer episodic memory accuracy for older than younger adults; however, age-related changes in the decision mechanisms in memory have received much less attention. Response bias, the willingness to endorse an item as remembered, is an important decision factor that contributes to episodic memory performance, and therefore understanding age-related changes in response bias is critical to theoretical development. We manipulate list strength in order to investigate two aspects of response bias. First, we evaluate whether criterion placement in episodic memory differs for older and younger adults. Second, we ask whether older adults have the same degree of flexibility to adjust the criterion in response to task demands as younger adults. Participants were tested on weakly and strongly encoded lists where word frequency (Experiment 1) or similarity between targets and foils (Experiment 2) was manipulated. Both older and younger adults had higher hit rates and lower false-alarm rates for strong lists than for weak lists (i.e., a strength-based mirror effect). Older adults were more conservative (less likely to endorse an item as studied) than younger adults, and we found no evidence that older and younger adults differ in their ability to flexibly adjust their criterion based on the demands of the task. [ABSTRACT FROM PUBLISHER]

Background/Study Context: Older adults exhibit an age-related deficit in item memory as a function of the length of the retention interval, but older adults and young adults usually show roughly equivalent benefits due to the spacing of item repetitions in continuous memory tasks. The current experiment investigates the seemingly paradoxical effects of retention interval and spacing in young and older adults using a continuous recognition memory procedure. Methods: Fifty young adults and 52 older adults gave memory confidence ratings to words that were presented once (P1), twice (P2), or three times (P3), and the effects of the lag length and retention interval were assessed at P2 and at P3, respectively. Results: Response times at P2 were disproportionately longer for older adults than for younger adults as a function of the number of items occurring between P1 and P2, suggestive of age-related loss in item memory. Ratings of confidence in memory responses revealed that older adults remembered fewer items at P2 with a high degree of certainty. Confidence ratings given at P3 suggested that young and older adults derived equivalent benefits from the spacing between P1 and P2. Conclusion: Findings of this study support theoretical accounts that suggest that recursive reminding and/or item retrieval difficulty promote item retention in older adults. [ABSTRACT FROM PUBLISHER]