首页 | 本学科首页   官方微博 | 高级检索  
相似文献
 共查询到20条相似文献,搜索用时 46 毫秒
1.
We model the cultural transmission of sign language when there is one-locus genetic variation for deafness and hearing. Our premises are that the deaf are more motivated to learn sign language than the hearing, and that a vertically transmitted sign language, unlike recessive hereditary deafness, cannot "jump a generation." Conditions are obtained for persistence (i.e. protection from loss) of signers. These conditions are more easily satisfied the greater the fraction of the hearing who also learn sign language and as the frequency of the recessive gene for deafness increases. Persistence is also facilitated by assortative mating for deafness, but not by assortment for signing. With vertical transmission only, it is necessary that one signer parent be able to transmit sign language with greater than one-half the efficiency of two. Under the assumption that the hearing do not learn sign language, the following additional results are obtained. Persistence is more likely with dominant as opposed to recessive inheritance. When recessive hereditary and acquired deafness co-occur, increasing the frequency of the latter has opposite effects depending on the degree of assortment. Opportunities for the deaf to learn sign language outside the family seem not to affect the conditions for persistence.  相似文献   

2.
Goodrich LV 《Neuron》2005,45(1):3-5
Our senses of hearing and balance rely on the function of specialized receptor neurons called "hair cells." In this issue of Neuron, Grant et al. report a series of elegant zebrafish experiments that reveal a previously unappreciated role for glia in the regulation of hair cell proliferation and differentiation. This work is a beautiful example of how zebrafish are particularly useful model systems for studying hair cell development and function.  相似文献   

3.
Two seemingly disparate areas of English language structure—the grammar of reported speech and of textual cohesion—are functionally related in that both entail a distinction between "wording" and "meaning." This is consistent with the Western ideological disjunction between language and reality, talk and action. Neither these language structures nor this linguistic ideology are found among the Ngarinyin people of northwestern Australia, suggesting a Whorfian hypothesis about their possible interrelationship.  相似文献   

4.
Happy Art     
This article looks at how arts integration can boost the language development of limited English proficient students in kindergarten through second grade. I first review existing research on how young children learn and describe the special challenges faced by children who must learn in an unfamiliar language. I then identify arts-based mechanisms that boost the language development of limited English proficient students and examine strategies used by a successful urban arts-and-literacy program to enhance the language development of English language learners in the primary grades.  相似文献   

5.
In an earlier "Forum" article in this journal, Brad Allenby outlined his views of a new approach to managing the unintended consequences of human activity, "earth systems engineering." He argues that we must develop the tools, institutions, and moral and ethical systems to allow us to "assume an active management role for most global systems." I believe this to be a significant departure from a core concept of industrial ecology: learning from ecosystems how the natural world operates to be able to more effectively design and manage coupled human-natural systems. Such lessons are more likely to lead away from tightly managed, centralized approaches, and favor approaches with as little intervention as feasible. More important, I believe that we are far less likely to learn how to implement earth systems engineering than simpler approaches, hence less likely to minimize environmental damage.  相似文献   

6.
When teaching and learning about alveolar ventilation with our class of 300 first-year medical students, we use four simple, inexpensive "models." The models, which encourage research-oriented learning and help our students to understand complex ideas, are distributed to the students before class. The students anticipate something new every day, and the models provide elements of surprise and physical examples and are designed to help students to understand 1) cohesive forces of the intrapleural space, 2) chest wall and lung dynamics, 3) alveolar volumes, and 4) regional differences in ventilation. Students are drawn into discussion by the power of learning that is associated with manipulating and thinking about objects. Specifically, the models encourage thinking about complex interactions, and the students appreciate manipulating objects and actually understanding how they work. Using models also allows us to show students how we think as well as what we know. Finally, students enjoy taking the models home to demonstrate to friends and family "how the body works" as well as use the models as future study aids.  相似文献   

7.
In the course of interviews with Israeli women who had recently been treated for breast cancer, we found that our informants tended to offer us "treatment narratives" rather than, or sometimes in addition to, the "illness narratives" made famous by Arthur Kleinman. For the women we interviewed, treatment narratives constitute verbal platforms on which to explore what it means to be human during a period in which one's body, spirit, and social identity are undergoing intense transformations. A central theme in these narratives is the Hebrew word yachas, loosely translated as "attitude," "attention," or "relationship." The women consistently contrasted the good yachas of medical staff who treated them "like humans" or like "real friends" with the bad yachas of staff who treated them like numbers, machines, or strangers. We argue that the women used language (in various contexts) as a means of resisting the medical culture's pattern of treating patients as "nonhumans."  相似文献   

8.
We all expect our students to learn facts and concepts, but more importantly, we want them to learn how to evaluate new information from an educated and skeptical perspective; that is, we want them to become critical thinkers. For many of us who are scientists and teachers, critical thought is either intuitive or we learned it so long ago that it is not at all obvious how to pass on the skills to our students. Explicitly discussing the logic that underlies the experimental basis of developmental biology is an easy and very successful way to teach critical thinking skills. Here, I describe some simple changes to a lecture course that turn the practice of critical thinking into the centerpiece of the learning process. My starting point is the "Evidence and Antibodies" sidelight in Gilbert's Developmental Biology (2000), which I use as an introduction to the ideas of correlation, necessity and sufficiency, and to the kinds of experiments required to gather each type of evidence: observation ("show it"), loss of function ("block it") and gain of function ("move it"). Thereafter, every experiment can be understood quickly by the class and discussed intelligently with a common vocabulary. Both verbal and written reinforcement of these ideas dramatically improve the students' ability to evaluate new information. In particular, they are able to evaluate claims about cause and effect; they become experts at distinguishing between correlation and causation. Because the intellectual techniques are so powerful and the logic so satisfying, the students come to view the critical assessment of knowledge as a fun puzzle and the rigorous thinking behind formulating a question as an exciting challenge.  相似文献   

9.
A survey carried out in Lake Tana in 2015 found that Hg levels in some fish species exceeded internationally accepted safe levels for fish consumption. The current study assesses human exposure to Hg through fish consumption around the Lake Tana. Of particular interest was that a dietary intake of fishes is currently a health risk for Bihar Dar residents and anglers. Hair samples were collected from three different groups: anglers, college students and teachers, and daily laborers. A questionary includes gender, age, weight, activity. Frequency of fish consumption and origin of the eaten fish were completed by each participant. Mercury concentrations in hair were significantly higher (P value <0.05) for anglers (mean?±?standard deviation 0.120?±?0.199 μg/g) than college students (mean?±?standard deviation 0.018?±?0.039 μg/g) or daily workers (mean?±?standard deviation 16?±?9.5 ng/g). Anglers consumed fish more often than daily workers and college group. Moreover, there was also a strong correlation (P value <0.05) between the logarithms of total mercury and age associated with mercury concentration in scalp hair. Mercury concentrations in the hair of men were on average twice the value of the women. Also, users of skin lightening soap on a daily basis had 2.5 times greater mercury in scalp hair than non-users. Despite the different sources of mercury exposure mentioned above, the mercury concentrations of the scalp hair of participants of this study were below levels deemed to pose a threat to health.  相似文献   

10.
Subjectivity, gender, and language are examined among contemporary Creek Indians of northeastern Oklahoma. Creek men are shown to define and shape social reproduction. Women's generality and unbounded "flow," such as that signified by menstruation, provide vitality and growth that force the separation of men from women and signal their definition as "separate(d) people." Creek language use is shown to be organized through these mutually interdependent principles of gendered subjectivity.  相似文献   

11.
The freedom of a doctor to treat an individual patient in the way he believes best has been markedly limited by the concept of evidence-based medicine. Clearly all would wish to practice according to the best available evidence, but it has become accepted that "evidence-based" means that which is derived from randomized, and preferably double-blind, clinical trials. The history of clinical trial development, which can be traced to the use of oranges and lemons for the treatment of scurvy in 1747, has reflected a progressive need to establish whether smaller and smaller effects of treatment are real. It has led to difficult concepts such as "equivalence" and aberrations such as "meta-analysis." An examination of evidence-based practice shows that it has usually been filtered through the opinions of experts and journal editors, and "opinion-based medicine" would be a more appropriate term. In the real world of individual patients with multiple diseases who are receiving a number of different drugs, the practice of evidence-based (or even opinion-based) medicine is extremely difficult. For each patient a judgment has to be made by the clinician of the likely balance of risks and benefits of any therapy. Good practice still requires clinical freedom for doctors.  相似文献   

12.
Functional Neuroanatomy is a course designed to help students learn the function and anatomy of the human nervous system. Historically, students have had difficulty with the spinal tract curricular unit and frequently resorted to memorization to "learn" the material. They performed poorly on exams and failed to demonstrate competence in the functional application of their knowledge. In an effort to improve learning and promote critical thinking in this course, the instructor revised the curriculum to include 1) shorter, less detailed lectures; 2) a set of practice problems that presented the spinal tracts in an applied context; and 3) a manipulative, which was composed of a magnetic bulletin board and a kit of magnets representing structures of the nervous system. Student learning, as assessed by summative exams, improved under the revised curriculum. Scores on knowledge, analytical, and synthesis questions were significantly higher than scores from previous classes using the traditional lecture curriculum (P < 0.05). This curricular protocol could potentially be applied to other topics where students resort to memorization and fail to comprehend concepts and processes.  相似文献   

13.
In this article, a linguistic anthropologist reviews the growing literature on the possibilities and problematics of understanding "native" anthropology and its implications for the construction of ethnographic knowledge. The author examines the centrality of language for "native" scholars in negotiating their legitimacy in the field. Confessions of failure by native scholars and their dilemmas with translation illuminate the dialogic and political nature of ethnographic inquiry, particularly when research is conducted in "home" communities. Moreover, native ethnographers' critical reflexivity regarding their subject positionings and "voice" may constitute a counterhegemonic rhetorical strategy for negotiating multiple accountabilities. Self-identification as a native scholar is seldom a means through which researchers "play the native card" via a noncritical privileging of their "insider" status. Instead, claiming native status may act tactically as both a normalizing and an exclusivizing endeavor, as well as a signif ier of the decolonization of anthropological thought and practice. The author considers these and other critical implications of native anthropological research in relation to her own multisited research on African American linguistic and cultural practices focused on hair care. [Keywords: "native" anthropology, language, representation, reflexivity, translation]  相似文献   

14.
A member of the cellulose synthase-like (subfamily D) gene family of Arabidopsis, AtCSLD3, has been identified by T-DNA tagging. The analysis of the corresponding mutant, csld3-1, showed that the AtCSLD3 gene plays a role in root hair growth in plants. Root hairs grow in phases: First a bulge is formed and then the root hair elongates by polarized growth, the so-called "tip growth." In the mutant, root hairs were initiated at the correct position and grew into a bulge, but their elongation was severely reduced. The tips of the csld3-1 root hairs easily leaked cytoplasm, indicating that the tensile strength of the cell wall had changed at the site of the tip. Based on the mutant phenotype and the functional conservation between CSLD3 and the genuine cellulose synthase proteins, we hypothesized that the CSLD3 protein is essential for the synthesis of polymers for the fast-growing primary cell wall at the root hair tip. The distinct mutant phenotype and the ubiquitous expression pattern indicate that the CSLD3 gene product is only limiting at the zone of the root hair tip, suggesting particular physical properties of the cell wall at this specific site of the root hair cell.  相似文献   

15.
The hair of 132 healthy subjects between 6 and 40 yr old living in the Veneto region in Italy was analyzed by means of HPLC method in order to determine the presence of zinc, copper, nickel, manganese, and lead. The collected samples were subdivided on the basis of age (6–11 and 19–40 yr), and sex and color (black, red, brown, and blond). From the data some evident differences were emphasized. In female hair the content of metals was higher than in male hair independently of color. Blond hair gave the lowest concentration values of the elements studied independently of sex. The maximum amount of the metals was found generally in black hair, followed by red and brown hair. Age seems to have a different influence, with the copper element decreasing appreciably in brown and blond female hair as the age of the subjects increased.  相似文献   

16.
Basque-versus Spanish-schooled students in San Sebastian, Spain, understand ethnic identity differently. The former are more likely to speak Basque and to consider the Basque language key to Basque identity. The latter are more likely to claim "biethnic" identities based on territory. The Basque case suggests that an understanding of educational efforts to reverse language shift require an examination of the language ideologies reigning in popular culture, the public sphere, and the home and school domains.  相似文献   

17.
Ethics should be an important component of physiological education. In this report, we examined to what extent teaching of ethics is formally being incorporated into the physiology curriculum. We carried out an e-mail survey in which we asked the e-mail recipients whether their institution offered a course or lecture on ethics as part of the physiology teaching process at their institution, using the following query: "We are now doing an online survey in which we would like to know whether you offer a course or a lecture on ethics as part of your physiology teaching curriculum." The response rate was 53.3%: we received 104 responses of a total of 195 sent out. Our responses came from 45 countries. While all of our responders confirmed that there was a need for ethics during medical education and scientific training, the degree of inclusion of formal ethics in the physiology curriculum varied widely. Our survey showed that, in most cases (69%), including at our Medical University of Graz, ethics in physiology is not incorporated into the physiology curriculum. Given this result, we suggest specific topics related to ethics and ethical considerations that could be integrated into the physiology curriculum. We present here a template example of a lecture "Teaching Ethics in Physiology" (structure, content, examples, and references), which was based on guidelines and case reports provided by experts in this area (e.g., Benos DJ. Ethics revisited. Adv Physiol Educ 25: 189-190, 2001). This lecture, which we are presently using in Graz, could be used as a base that could lead to greater awareness of important ethical issues in students at an early point in the educational process.  相似文献   

18.
Outreach efforts by faculty members are oftentimes limited in scope due to hectic schedules. We developed a program to enhance science literacy in elementary school children that allows experts to reach a tremendous audience while minimizing their time commitment. The foundation of the program is a television series entitled "Desert Survivors." The episodes air on local cable access television and are available to teachers on DVD. Each episode features a guest expert who spotlights a particular organism and how that organism overcomes the myriad of hardships inherent to desert survival. Local classrooms are visited to solicit questions from students regarding the organism of interest. These videotaped questions are integrated into Desert Survivors television production and provide the guest expert with the basis to discuss the ecology, physiology, and evolutionary biology of the organism. The program is bolstered through the use of an interactive website. Assessment strategies are in place to ensure program efficacy. Herein, we describe the development of the program as a model for innovative outreach opportunities.  相似文献   

19.
Pinschers affected by coat color dilution show a specific pigmentation phenotype. The dilute pigmentation phenotype leads to a silver-blue appearance of the eumelanin-containing fur and a pale sandy color of pheomelanin-containing fur. In Pinscher breeding, dilute black-and-tan dogs are called "blue," and dilute red or brown animals are termed "fawn" or "Isabella fawn." Coat color dilution in Pinschers is sometimes accompanied by hair loss and a recurrent infection of the hair follicles. In human and mice, several well-characterized genes are responsible for similar pigment variations. To investigate the genetic cause of the coat color dilution in Pinschers, we isolated BAC clones containing the canine ortholog of the known murine color dilution gene Mlph. RH mapping of the canine MLPH gene was performed using an STS marker derived from BAC sequences. Additionally, one MLPH BAC clone was used as probe for FISH mapping, and the canine MLPH gene was assigned to CFA25q24.  相似文献   

20.
Discussing the ethical issues involved in topics such as cloning and stem cell research in a large introductory biology course is often difficult. Teachers may be wary of presenting material biased by personal beliefs, and students often feel inhibited speaking about moral issues in a large group. Yet, to ignore what is happening "out there" beyond the textbooks and lab work is to do a disservice to students. This essay describes a semester-long project in which upperclass students presented some of the most complex and controversial ideas imaginable to introductory students by staging a mock debate and acting as members of the then newly appointed President's Council on Bioethics. Because the upperclass students were presenting the ideas of real people who play an important role in shaping national policy, no student's personal beliefs were put on the line, and many ideas were articulated. The introductory audience could accept or reject what they were hearing and learn information important for making up their own minds on these issues. This project is presented as an example of how current events can be used to put basic cell biology into context and of how exciting it can be when students teach students.  相似文献   

设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号