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In the early 1920s, the continental displacement theory of Wegener, latitude studies of Koppen and Wegener, and Argand's ideas on mountain building led to the first mobilistic paleogeography. In the 1930s and 1940s, many factors c...
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In the early 1920s, the continental displacement theory of Wegener, latitude studies of Koppen and Wegener, and Argand's ideas on mountain building led to the first mobilistic paleogeography. In the 1930s and 1940s, many factors caused its general abandonment. Mobilism was revived in the 1950s and 1960s by measurements of long-term displacement of crustal blocks relative to each other (tectonic displacement) and to Earth's geographic pole (latitudinal displacement). Also, short-term or current displacements can now be measured. I briefly outline the categories of tectonic and current displacement and focus on latitudinal displacement. Integration of tectonic and latitudinal displacement in the early 1970s completed the new mobilistic paleogeography, in which the transformation of rock magnetization directions into paleopoles and latitudes and the finite rotation of spherical plates about pivot points play complementary roles; this new synthesis now provides a quantitative basis for studying long-term evolution of Earth's surface features and climate, the changing environments in which life evolves.
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Actin dynamics is fundamental for neurite development; monomer depolymerization from pointed ends is rate-limiting in actin treadmilling. Tropomodulins (Tmod) make up a family of actin pointed end-capping proteins. Of the four kno...
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Actin dynamics is fundamental for neurite development; monomer depolymerization from pointed ends is rate-limiting in actin treadmilling. Tropomodulins (Tmod) make up a family of actin pointed end-capping proteins. Of the four known isoforms, Tmod1?Tmod3 are expressed in brain cells. We investigated the role of Tmod’s C-terminal (LRR) domain in the formation of neurite-like processes by overexpressing Tmod1 and Tmod2 with deleted or mutated LRR domains in PC12 cells, a model system used to study neuritogenesis. Tmod1 overexpression results in a normal quantity and a normal length of processes, while Tmod2 overexpression reduces both measures. The Tmod2 overexpression phenotype is mimicked by overexpression of Tmod1 with the LRR domain removed or with three point mutations in the LRR domain that disrupt exposed clusters of conserved residues. Removal of Tmod2’s LRR domain does not significantly alter the outgrowth of neurite-like processes compared to that of Tmod2. Overexpression of chimeras with the N-terminal and C-terminal domains switched between Tmod1 and Tmod2 reinforces the idea that Tmod1’s LRR domain counteracts the reductive effect of the Tmod N-terminal domain upon formation of processes while Tmod2’s LRR domain does not. We suggest that the TM-dependent actin capping ability of both Tmods inhibits the formation of processes, but in Tmod1, this inhibition can be controlled via its LRR domain. Circular dichroism, limited proteolysis, and molecular dynamics demonstrate structural differences in the C-terminal region of the LRR domains of Tmod1, Tmod2, and the Tmod1 mutant.
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Cowpea, also known as black-eyed pea, is one of the most promising foods for nutritional improvement for many African countries. Cowpea—including its seeds, young pods, and leaves—supplies essential nutrients, such as high-quali...
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Cowpea, also known as black-eyed pea, is one of the most promising foods for nutritional improvement for many African countries. Cowpea—including its seeds, young pods, and leaves—supplies essential nutrients, such as high-quality protein. It is also of vital importance to the livelihood of many people in West Africa as a cash crop. In August 2018, we conducted a survey on 206 households in rural villages in Yako and Po, located in northern and southern Burkina Faso, respectively. We compared the cowpea production at the family plot and women’s plot levels, and the usages of cowpea seeds, leaves and pods between these two climatically and culturally different regions. Cowpea production in family plots is quite popular in both regions, suggesting that cowpea should no longer be considered just a “women’s crop.” Different varieties of crops are sold in the south, whereas cowpea is a major cash crop in the north. Regarding cowpea usage, all households in the north consume not only cowpea seeds but also the young pods and leaves, whereas some households in the south only consume the seeds. No households in the north use cowpea as a baby food, despite its nutritious content when properly prepared. These findings suggest the need to promote further utilization of cowpea in different forms in order to maximize its potential.
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C1s is the modular serine protease responsible for cleavage of C4 and C2, the protein substrates of the first component of C (C1). Its catalytic domain comprises two complement control protein (CCP) modules connected by a four-res...
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C1s is the modular serine protease responsible for cleavage of C4 and C2, the protein substrates of the first component of C (C1). Its catalytic domain comprises two complement control protein (CCP) modules connected by a four-residue linker Gln(340)-Pro-Val-Asp(343) and a serine protease domain. To assess the functional role of the linker, a series of mutations were performed at positions 340-343 of human C1s, and the resulting mutants were produced using a baculovirus-mediated expression system and characterized functionally. All mutants were secreted in a proenzyme form and had a mass of 77,203-77,716 Da comparable to that of wild-type C1s, except Q340E, which had a mass of 82,008 Da, due to overglycosylation at Asn(391). None of the mutations significantly altered C1s ability to assemble with C1r and C1q within C1. Whereas the other mutations had no effect on C1s activation, the Q340E mutant was totally resistant to C1r-mediated activation, both in the fluid phase and within the C1 complex. Once activated, all mutants cleaved C2 with an efficiency comparable to that of wild-type C1s. In contrast, most of the mutations resulted in a decreased C4-cleaving activity, with particularly pronounced inhibitory effects for point mutants Q340K, P341I, V342K, and D343N. Comparable effects were observed when the C4-cleaving activity of the mutants was measured inside C1. Thus, flexibility of the C1s CCP(1)-CCP(2) linker plays no significant role in C1 assembly or C1s activation by C1r inside C1 but plays a critical role in C4 cleavage by adjusting positioning of this substrate for optimal cleavage by the C1s active site.
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This study aims to find out the parents’ involvement on their children’s’ educational attainment in mathematics from the teachers’ perspective ? in particular. The qualitative approach was actively employed. Besides, a sample ...
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This study aims to find out the parents’ involvement on their children’s’ educational attainment in mathematics from the teachers’ perspective ? in particular. The qualitative approach was actively employed. Besides, a sample of experienced teachers and educators was taken. The sample consists of 13 male and female teachers with whom the notion of parents’ involvement was discussed, challenges of parents’ involvement, to what extent it might be effective, the purpose of parents’ involvement and how parents could be helpful to the academic staff throughout the educational process, and the impact of such involvement on the value system. In accordance with the research results; all teachers were in favour of parents’ involvement. Parents’ involvement, according to the interviewed teachers, is vital for the success of the educational process. Some teachers, however, viewed? parents’ involvement as a threat to the school staff, i.e. they prefer a controlled level of involvement that does not preach the teacher’s own work space and freedom. Some teachers expressed the problem with parents’ involvement in the fact that some parents lack the necessary level of awareness. Based on the research findings; I recommend a broader parents’ involvement. The prior is in favour of children’s educational attainment. Besides, specialized courses for parents should be seriously considered in order to raise their awareness. In the Negev region, for instance, parents’ involvement is extremely limited due to polygamy, work burden and other social problems.
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In contrast to accounts that explain increases in women’s political representation by reference to structural and institutional factors, this article draws attention to the agency of women candidates. The number of women elected ...
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In contrast to accounts that explain increases in women’s political representation by reference to structural and institutional factors, this article draws attention to the agency of women candidates. The number of women elected in the Eastern Indonesian province of East Nusa Tenggara ( Nusa Tenggara Timur, NTT) increased markedly in 2019. To explain this increase, this article highlights the remarkable persistence of women candidates, many of whom succeeded in 2019 only after competing in multiple prior elections, slowly building their personal political skills and reputations. The article also draws attention to the effects of positive female role models – showing how a female candidate in a gubernatorial race inspired other women politicians – and the positive effects that can arise from co-operation among women candidates. It shows that, despite the emphasis on male dominance and dynastic power in much of the literature on Indonesian politics, there are still pathways to power for women with origins in the grassroots.
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Although research supports the stigma and labeling perspective, empirical evidence also indicates that a social safety net remains intact for those with mental illness, recalling the classic "sick role" concept. Here, insights fro...
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Although research supports the stigma and labeling perspective, empirical evidence also indicates that a social safety net remains intact for those with mental illness, recalling the classic "sick role" concept. Here, insights from social networks theory are offered as explanation for these discrepant findings. Using data from individuals experiencing their first contact with the mental health treatment system, the effects of diagnosis and symptoms on social networks and stigma experiences are examined. The findings suggest that relative to those with less severe affective disorders, individuals with severe diagnoses and more visible symptoms of mental illness have larger, more broadly functional networks, as well as more supporters who are aware of and sympathetic toward the illness situation. However, those with more severe diagnoses are also vulnerable to rejection and discrimination by acquaintances and strangers. These findings suggest that being formally labeled with a mental illness may present a paradox, simultaneously initiating beneficial social processes within core networks and detrimental ones among peripheral ties.
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As global populations age, it is imperative that nurses have a knowledge base on the topic of elder abuse. Elder abuse can occur in any environment, but is most prevalent in the community setting. Older people may experience eithe...
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As global populations age, it is imperative that nurses have a knowledge base on the topic of elder abuse. Elder abuse can occur in any environment, but is most prevalent in the community setting. Older people may experience either a single type of abuse or several forms of abuse concurrently. It is also important that abuse at an institutional and societal level is recognized and addressed. Nurses have a responsibility to identify when abuse may be perpetrated and to assess the context, ensuring appropriate responses are undertaken. A knowledge of barriers to disclosure is also essential, as well as ensuring that the voice of the older person is prioritized in case management. In doing so, nurses have the ability to both prevent and provide early intervention to safeguard older people.
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A remarkable contribution of Professor Cyril Stanley Smith was the translation of metallurgical classics into English from several languages -both ancient and modern.
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The present study was designed to investigate the influence of children’s books in promoting nontraditional career aspirations of primary school girls in Zimbabwe. Children who used specially written readers that contained biogra...
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The present study was designed to investigate the influence of children’s books in promoting nontraditional career aspirations of primary school girls in Zimbabwe. Children who used specially written readers that contained biographic sketches of women role models in nontraditional careers comprised the treatment group; the control group consisted of non-user children. Survey data were collected from these subgroups using multiple data collection techniques. Analysis indicates that career preferences of the treatment group were not conditional on background characteristics. As expected, analysis of post-treatment perceptions showed that girls had significantly greater interest in the careers of role models than did boys. Finally, the former also expressed more interest in nontraditional occupations during post-test analysis than the control group did.
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