Summary: The polymorphisms in poly(hexamethylene terephthalate) (PHT), along with their associated melting and spherulite morphologies, were examined by differential scanning calorimetry (DSC), wide‐angle X‐ray diffraction (WAXD), and polarized‐light microscopy (PLM). The morphology and crystal cells were dependent on the temperature of crystallization. When melt‐crystallized at low temperatures (90–135 °C), PHT showed at least five melting peaks and two re‐crystallization peaks upon DSC scanning, and the samples displayed various fractions of both α and β crystals. However, only a single melting peak was obtained in PHT melt‐crystallized at 140 °C or above, which displayed a single type of β crystal. In addition, two different forms of spherulites were identified in melt‐crystallized PHT, with one being a typical Maltese‐cross spherulite containing the α crystal, and the other being a dendrite‐type packed mainly with the β crystal. This study provides timely evidence for a critical interpretation of the relationship between multiple melting and polymorphisms (unit cells and spherulites) in polymers, including semi‐crystalline polyesters.

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As the coronavirus disease of 2019 (COVID-19) pandemic disrupted all aspects of life, parents have been subjected to more household and caregiving responsibilities and stressors. The purpose of this study is to investigate how hope, self-compassion, and perception of COVID-19 health risks influence parenting stress. In this cross-sectional study, a total of 362 parents living in the United States completed an online survey in July 2020. Multiple regression analyses revealed that higher levels of hope are related to lower levels of parenting stress. On the other hand, lower levels of self-compassion as indicated by higher scores on the subscales of isolation, self-judgment, and overidentification are related to higher levels of parenting stress. Further, testing positive for the coronavirus is positively related to parenting stress, whereas the belief that COVID-19 is a serious disease is negatively related to parenting stress. Findings also revealed the significant role of hope in moderating the relation between self-compassion and parenting stress. This study highlights the importance of nurturing and drawing from one’s own psychological resources to mitigate parenting stress, particularly in the context of a chronic source of stress like a pandemic. Implications for the counseling profession are discussed.

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