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101.
Adenosine diphosphate(ADP)-ribosylation is a unique post-translational modification that regulates many biological processes,such as DNA damage repair.During DNA repair,ADP-ribosylation needs to be reversed by ADP-ribosylhydrolases.A group of ADP-ribosylhydrolases have a catalytic domain,namely the macrodomain,which is conserved in evolution from prokaryotes to humans.Not all macrodomains remove ADP-ribosylation.One set of macrodomains loses enzymatic activity and only binds to ADP-ribose(ADPR).Here,we summarize the biological functions of these macrodomains in DNA damage repair and compare the structure of enzymatically active and inactive macrodomains.Moreover,small molecular inhibitors have been developed that target macrodomains to suppress DNA damage repair and tumor growth.Macrodomain proteins are also expressed in pathogens,such as severe acute respiratory syndrome coronavirus 2(SARS-CoV-2).However,these domains may not be directly involved in DNA damage repair in the hosts or pathogens.Instead,they play key roles in pathogen replication.Thus,by targeting macrodomains it may be possible to treat pathogen-induced diseases,such as coronavirus disease 2019(COVID-19).  相似文献   
102.
Stress is one of the basic factors in the aetiology of a number of diseases such as atherosclerosis, coronary heart disease, aging, liver disease etc. Hence this work was designed to study the effect of stress in the form of forced immobilisation stress on lipid peroxidation and lipid profile in rabbits. The study was conducted in 25 healthy rabbits of either sex. Rabbits were subjected to forced immobilisation for two hours everyday for consecutive seven days. Blood samples were collected on day 1, 3 and 7 after immobilisation period. Malondialdehyde (MDA), a marker of lipid peroxidation was estimated by TBA assay method. Lipid profile was analysed by multichannel autoanalyser. There was statistically significant increase in MDA, total cholesterol, LDL, VLDL and triglycerides with immobilisation. These findings indicate that stress in the form of forced immobilisation increases lipid peroxidation and alter lipid profile, which may be responsible for pathophysiology of various diseases.  相似文献   
103.
In a theoretical examination of the structures of liquid crystal phases, Robert B. Meyer in 1975 creatively utilized symmetry arguments to predict that tilted, layered liquid crystal phases of chiral molecules are ferroelectric. He then engaged the help of organic chemists to synthesize a compound that might possess such a phase, and once the material was in his hands, Meyer not only verified its ferroelectricity, but also suggested how such a phase could be used for extremely fast displays. This discovery of ferroelectricity in a fluid system with the possibility for unique applications surprised the entire condensed matter research community and quickly paved the way for both increased scientific understanding and significant technological advancement. For this creative synthesis of theory and experiment, Meyer was awarded the 2004 Benjamin Franklin Medal in Physics.  相似文献   
104.
A trie represented by a double-array enables us to search a key fast with a small space. However, the double-array uses extra space to be updated dynamically. This paper presents a compact structure for a static double-array. The new structure keeps character codes instead of indices in order to compress elements of the double-array. In addition, the new structure unifies common suffixes and consists of less elements than the old structure. Experimental results for English keys show that the new structure reduces space usage of the double-array up to 40%.  相似文献   
105.
In this paper we argue that the processes of collaborative creativity are just as important within the sociocultural context of PhD supervisory practice, as they are in other organizational and educational settings. In order to test this claim a series of interviews with supervisors and students were undertaken to uncover the pedagogic processes used to encourage and support creativity within supervision sessions. The findings from this small-scale study suggest that whilst the more formal instruction and monitoring processes that lead to the acquisition of transferrable research skills are both usefully and necessary aspects of doctoral training, the more open-ended and creative developments required at this level of study should be given equal weight. There needs to be space, time and encouragement for the types of interactions identified here (e.g. informal reflection, relationship building with peers and supervisor, playful exploration and risk taking) as well as mandatory skills development.  相似文献   
106.
107.
This qualitative study focuses on what contributes to making a music information-seeking experience satisfying in the context of everyday life. Data were collected through in-depth interviews conducted with 15 younger adults (18 to 29 years old). The analysis revealed that satisfaction could depend on both hedonic (i.e., experiencing pleasure) and utilitarian outcomes. It was found that two types of utilitarian outcomes contributed to satisfaction: (1) the acquisition of music, and (2) the acquisition of information about music. Information about music was gathered to (1) enrich the listening experience, (2) increase one's music knowledge, and/or (3) optimize future acquisition. This study contributes to a better understanding of music information-seeking behavior in recreational contexts. It also has implications for music information retrieval systems design: results suggest that these systems should be engaging, include a wealth of extra-musical information, allow users to navigate among music items, and encourage serendipitous encountering of music.  相似文献   
108.
This paper addresses a new case for the convergent regulatory institution for broadcasting and telecommunications in Korea. This paper emphasizes that, when considering a convergent regulatory body, Korea's main principle to establish is a reflection of the paradigm shift of convergence and IT industry. The proposal of the Korean Communications Commission addresses that as a prior factor. This paper deals with three characteristics in establishing the KCC: accommodating policy making and regulation together within a single institution; choosing a commission model as a new organizational type, which inherits a broadcasting legacy to ensure diversity and independence; combining content and network sector together. This paper attempts to show that the Korean model gives a power to the convergent regulatory institution to make the country remain one of the leading countries in information and communication sector as well as implement convergence of broadcasting and telecommunications successfully.  相似文献   
109.
This article addresses the widely debated question of whether online communication through the Internet will fulfill its potential to enhance democratic processes in society. The paper reports the findings of a survey of groups engaged in some form of civic activity, in both online and offline groups. Comparisons are drawn between the responses of those engaged in both types of group to determine whether the motivations, behavior, and satisfaction of participants differ because of the medium of communication. Contrary to some expectations in the literature, the findings suggest that participants in online groups are marginally less satisfied with their participation in their group. The findings have implications for politicians, policy makers, and groups engaged in civil society when using online channels of communication for democratic discourse.  相似文献   
110.
Governments worldwide are encouraging public agencies to join e-Government initiatives in order to provide better services to their citizens and businesses; hence, methods of evaluating the readiness of individual public agencies to execute specific e-Government programs and directives are a key ingredient in the successful expansion of e-Government. To satisfy this need, a model called the eGovernment Maturity Model (eGov-MM) was developed, integrating the assessment of technological, organizational, operational, and human capital capabilities, under a multi-dimensional, holistic, and evolutionary approach. The model is strongly supported by international best practices, and provides tuning mechanisms to enable its alignment with nation-wide directives on e-Government. This article describes how the model was conceived, designed, developed, field tested by expert public officials from several government agencies, and finally applied to a selection of 30 public agencies in Chile, generating the first formal measurements, assessments, and rankings of their readiness for e-Government. The implementation of the model also provided several recommendations to policymakers at the national and agency levels.  相似文献   
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