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91.
92.
References linking genes to complex human traits, such as personality type or disease susceptibility, abound in the news media and popular culture. In his book The God Gene: How Faith is Hardwired into Our Genes, Dean Hamer argues that a variation in the VMAT2 gene plays a role in one's openness to spiritual experiences. In a nonmajors class, we read and discussed The God Gene and conducted on a small scale an extension of the study it describes. Students used polymerase chain reaction to replicate a portion of their VMAT2 genes, and they analyzed three polymorphic sites in the sequence of these products. Associations between particular VMAT2 alleles and scores on a personality test were assessed by t test. The course, of which this project was a major part, stimulated student learning; scores on a test covering basic genetic concepts, causation/correlation, and laboratory methodology improved after completion of the course. In a survey, students reported the laboratory project aided their learning, especially in the areas of statistics and the linking of genes to behaviors. They reported high levels of engagement with the project, citing in particular its personal nature as motivating their interest.  相似文献   
93.
The goal of this article is to clarify how current dominant understandings of community-engaged scholarship (CES) can be strengthened to incorporate lessons from critical theory and to focus on justice more explicitly. A prior analysis of how CES is defined across multiple disciplinary literatures revealed that scholars define CES as partnerships between universities and communities that collaboratively develop and apply knowledge to address public issues. Six components of CES were frequently recommended for practice within this scholarship as well. However, neither the goal of CES—to support the “public good”—nor the six recommended CES components consistently included an explicit focus on justice and critical theory. By explicitly naming and defining the goal of justice—as opposed to the “public good” —I aim to highlight the importance of conducting routine analyses in CES of whose interests motivate conceptions of the public good and how dominant cultural structures, values, and traditions negatively impact minoritized community members' lives. Thus, this article employs teachings from critical theory—such as race-conscious analyses, asset-based understandings of community, and privileging subaltern experiences—to envision how critical CES could support university and community partnerships in producing knowledge that more effectively dismantles systemic sources of racial and social injustice.  相似文献   
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60CO-γ射线对枳种子辐射生物学效应的探讨   总被引:3,自引:0,他引:3       下载免费PDF全文
本文研究了^60Co-γ射线对枳种子的辐射生物学效应,结果表明:^60Co-γ射线对枳的发芽、出苗和生长的抑制随着剂量的加大而增强,相对电导率也随剂量的加大而增加,各处理都能不同程度地诱导白化苗、畸形苗等变异性状的产生。辐射半致死剂量(LD50)为9KR左右,临界剂量(LD40)在7KR附近.  相似文献   
96.
There is an overall perception of increased interdisciplinarity in science, but this is difficult to confirm quantitatively owing to the lack of adequate methods to evaluate subjective phenomena. This is no different from the difficulties in establishing quantitative relationships in human and social sciences. In this paper we quantified the interdisciplinarity of scientific journals and science fields by using an entropy measurement based on the diversity of the subject categories of journals citing a specific journal. The methodology consisted in building citation networks using the Journal Citation Reports® database, in which the nodes were journals and edges were established based on citations among journals. The overall network for the 11-year period (1999–2009) studied was small-world and followed a power-law with exponential cutoff distribution with regard to the in-strength. Upon visualizing the network topology an overall structure of the various science fields could be inferred, especially their interconnections. We confirmed quantitatively that science fields are becoming increasingly interdisciplinary, with the degree of interdisplinarity (i.e. entropy) correlating strongly with the in-strength of journals and with the impact factor.  相似文献   
97.
In this work, in order to model network traffic processes, an efficient multifractal model is proposed based on fewer parameters than other models present in the literature, called 2PEMV. The 2PEMV model (2-Parameter Exponential Modeling for Multipliers’ Variance) is based on a multiplicative cascade in the wavelet domain capable of synthesizing communication network traffic traces which present characteristics such as self-similarity and wide Multifractal Spectrum Width (MSW). For such a purpose, in the 2PEMV model, the energy decay of the wavelet coefficients is captured by means of an exponential modeling for the multipliers’ variance along the cascade scales. The performance of the 2PEMV model to represent the network traffic characteristics is evaluated in comparison to other models present in the literature through simulations that are carried out using real communication network traffic traces.  相似文献   
98.
This essay responds to Professor Aguirre’s article in this issue that explores through personal narrative the trials and tribulations of being a faculty member with an expertise in Chicana/o Studies. The author joins his exploration by introducing the structural disadvantages that Chicana/o Studies suffers as a field. She then expounds on what we have gained by developing a new field with an explicitly political focus that includes putting student interests at the center of its development while fighting for economic and social justice as an integral part of its intellectual agenda. Her conclusion explores the challenges that the field of Chicana/o Studies faces as we confront changing demographic and societal conditions.  相似文献   
99.
The main purpose of this study was to compare the effect of the constant load and self-paced exercise with similar total work on autonomic control after endurance exercise. Ten physically active men were submitted to (i) a maximal incremental exercise test, (ii) a 4-km cycling time trial (4-km TT), and (iii) a constant workload test with identical total external work performed at 4-km TT. Gas exchange was measured throughout the tests, while blood lactate, heart rate, and heart rate variability (HRV) were measured during the passive recovery. Power output measured at the last lap (i.e. 3600–4000?m) of 4-km TT (316?±?89?W) was statistically higher than power output measured at the end of the constant workload exercise (211?±?42?W). The 4-km TT produced higher values of blood lactate concentration (8.8?±?2.1?mmol?L?1) than the constant workload test (7.8?±?2.1?mmol?L?1). The heart rate recovery measured at 60?s (constant workload: 37?±?7?bpm; 4-km TT: 30?±?6) and 120?s (constant workload: 57?±?9?bpm; 4-km TT: 51?±?9?bpm) were higher in the constant workload than in the self-paced exercise. The HRV (i.e. RMSSD30s) was statistically higher in the constant load exercise measured at 120, 420, 450, 480, 540, and 570?s than the self-paced exercise. These findings suggest that the autonomic control responses were dependent of the endurance exercise modalities, with parasympathetic activity being delayed after self-paced exercise, as evidenced by post-exercise heart rate indices.  相似文献   
100.
The present study aimed to determine the effects of physical training performed by parents on mice offspring adiposity. Male and female parents underwent an aerobic training protocol for 7 weeks. The trained and sedentary parents were allowed to mate and the resultant offspring divided in: S (Offspring from Sedentary Parents), T (Offspring from Trained Parents), ST (Offspring from Sedentary Father and Trained Mother) and TS (Offspring from Trained Father and Sedentary Mother). After weaning, offspring was euthanized, blood collected and samples of mesenteric and inguinal fat pads used to isolate adipocytes for morphologic and histological analyses. Lee index, mesenteric fat pad, sum of visceral fat and total fat weight of female T was reduced in comparison to the other groups (p < 0.05). Periepididymal and sum of visceral fat in male T group was also reduced when compared to the other groups (p < 0.05). The diameter of mesenteric and inguinal adipocytes of T group was smaller compared to all groups comparisons for both sexes (p < 0.05). In summary, exercise training performed by parents reduced visceral offspring adiposity, the diameter of subcutaneous adipocytes and improved metabolic parameters associated to metabolic syndrome.  相似文献   
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