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121.
To investigate why men offer sperm donation via the internet, a questionnaire was disseminated via 39 Dutch-language websites thought to be visited by potential sperm donors. Nine internet donors completed the survey, men who typically knew the women they were donating to. Their responses were compared with those of a control group of 35 general sperm bank donors who were recruited using flyers in Dutch sperm banks, and who were typically unaware of the identity of the eventual recipients. The findings shed light on the motives and attitudes of internet donors. Both groups of donors indicated that their primary motivation for donating was altruism (>80% of all respondents). However, internet donors had a more pronounced desire to procreate than sperm bank donors (6 out of 9, i.e. 66 vs. 22%, respectively) and more often felt that they had good genes they wished to pass on (5 out of 9, i.e. 55 vs. 31%, respectively). The main reason internet donors gave for donating via the internet was that they wanted to know the prospective parents and be kept up to date on the progress of the offspring conceived from their donations. This distinguishes them significantly from sperm bank donors. A further finding was that they were not prompted to avoid the formal donation circuit for which, by law in the Netherlands, pregnancies resulting from donations have to be registered in a central database. This study is subject to several, in some cases inevitable, limitations, but it provides an interesting starting point that future studies can seek to confirm and extend. 相似文献
122.
von Keyserlingk Luise Rubach Charlott Lee Hye Rin Eccles Jacquelynne S. Heckhausen Jutta 《Motivation and emotion》2022,46(5):601-620
Motivation and Emotion - In college, students often encounter situations in which they struggle to meet their academic goals in difficult courses. We integrate the Motivational Theory of Life-Span... 相似文献
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Ohne ZusammenfassungHerrn Prof. Dr. Wolfgang Metzger zum 65. Geburtstag gewidmet. 相似文献
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This paper investigates how individuals deal with demands of social and economic change in the domains of work and family
when opportunities for their mastery are unfavorable. Theoretical considerations and empirical research suggest that with
unattainable goals and unmanageable demands motivational disengagement and self-protective cognitions bring about superior
outcomes than continued goal striving. Building on research on developmental deadlines, this paper introduces the concept
of developmental barriers to address socioeconomic conditions of severely constrained opportunities in certain geographical
regions. Mixed-effects methods were used to model cross-level interactions between individual-level compensatory secondary
control and regional-level opportunity structures in terms of social indicators for the economic prosperity and family friendliness.
Results showed that disengagement was positively associated with general life satisfaction in regions that were economically
devastated and has less than average services for families. In regions that were economically well off and family-friendly,
the association was negative. Similar results were found for self-protection concerning domain-specific satisfaction with
life. These findings suggest that compensatory secondary control can be an adaptive way of mastering a demand when primary
control is not possible. 相似文献
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This is a purely conceptual paper. It aims at presenting and putting into perspective the idea of a proof-theoretic semantics
of the logical operations. The first section briefly surveys various semantic paradigms, and Section 2 focuses on one particular
paradigm, namely the proof-theoretic semantics of the logical operations.
This revised version was published online in June 2006 with corrections to the Cover Date. 相似文献
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We formulate a Hilbert-style axiomatic system and a tableau calculus for the STIT-based logic of imagination recently proposed in Wansing (2015). Completeness of the axiom system is shown by the method of canonical models; completeness of the tableau system is also shown by using standard methods. 相似文献