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1.
While “Mendel's Laws” are generally taught as natural facts, they are actually pedagogical constructions, which originated in a series of lectures at Princeton in 1916. What accounts for their popularity?  相似文献   

2.
Butterfly assemblages were monitored by transect counts in a riverine area along Tamagawa River (RIV), a residential area on the plain (RES1), a residential area on the hill (RES2), the core area of the city (COR), the Tama Experimental Station of Forestry and Forest Products Research Institute (TES) and Tokyo Metropolitan Sakuragaoka Park (MSP) in Tama City, Tokyo, in 2005. The butterfly assemblages in forest‐dominated TES and MSP were more species‐rich than those in the other areas. The assemblage in the grassland‐dominated RIV was characterized by the highest abundance of individuals. Species richness and abundance were lowest in COR. Ordination of the areas by detrended correspondence analysis placed RIV, MSP and TES in increasing order of scores along axis 1, and RES1, RES2 and COR had higher scores along axis 2 than RIV, TES and MSP. In axis 1, grassland species had low scores and forest species high scores; the two groups were generally separated, coinciding with Tanaka's classification. However, the scores for two “forest species”, Papilio xuthus and Ypthima argus, were low and those for two “grassland species”, Potanthus flavus and Anthocharis scolymus, were high, challenging the validity of the classification. Most species recorded in this study were “seminatural type”, with relatively few “natural type” species, according to Sunose's classification. Most “urban type” species occurred in several different habitats and were not specific to highly human‐dominated RES1, RES2 and COR.  相似文献   

3.
The inter-individual differences of human time-of-day preferences could divide population into “morning”, “intermediate” and “evening” types. This variety of sleep patterns is accompanied by differences in the timing of peak cognitive performance. The morningness–eveningness trait, also known as chronotype, is distributed on a continuum, with unequivocal early morning and night owl types at the opposite extremes of the distribution while most of the population shows an intermediate or neither type weak sleep pattern. Obviously, the discrepancy between biological and the social clocks has a distinct impact on physiological processes in humans with different chronotype. It is known that natural light regime in circumpolar regions influences human performance. Most work focused on the relationship between academic achievement and chronotype in students from middle latitudes. The primary aim of our study is to investigate the relationship between chronotype and academic achievement in schoolchildren (6th–11th grade) from north-west Russia (Russian Karelia). The Munich chronotype questionnaire was used in the study, and all participants were required to answer a question about their school achievement. Early midpoint of sleep and longer average sleep duration were associated with better grades. Large social jetlag was associated with worse grades. In a linear regression, gender was the most important predictor of grades, followed by midpoint of sleep and age. This is the first study that has been carried out among school pupils from Russian Karelia, and it shows that evening orientation linked with poorer academic grades at this high latitude.  相似文献   

4.
5.
ABSTRACT

This study presents a new technique, the “Which plant am I?” game, which helps to increase pupils’ plant knowledge, while motivate them to become familiar with more plants. On the other hand pupils’ plant knowledge was tested in Serbia.

The “Which Plant Am I?“ game was tested with two groups of pupils (in average 11 years old). Pupils in the experimental group took part in outdoor classes and played the ”Which plant am I?” game. Pupils of the control group observed plants only in the classroom. This technique can deliver significant improvement in pupils’ knowledge about plants and motivate them through an active and playful learning process. This technique can be one possible solution of plant blindness.  相似文献   

6.
What has the past reaction to the COVID-19 pandemic taught us? We have seen that many low and middle-income countries (LMICs) still lack access to vaccines, and it seems little progress has been made in the last few months and year. This article discusses whether the current strategies, most notably, vaccine donations by the international community and the COVID-19 global access facility COVAX, offer meaningful solutions to tackle the problem. At the centre of our analysis, we compare the concepts of “donations” and “charity” with “vaccine equity” and the “empowerment” of poorer countries. We suggest that the achievement of fair global vaccine production requires that our global approach is supportive of the idea of empowerment. We, therefore, need structural reforms, which would most importantly include capacity building, to positively impact this goal and to take the interests of the global poor seriously.  相似文献   

7.
Thoughts about animal intelligence To give a short and clear definition of what means “animal intelligence” it's necessary to find the connection between different methods of “learning” processes: Habituation, trial and error resp. classical and instrumental conditioning, play behavior, imitation, insight learning and imprinting. Some examples try to explain animal intelligence by human mind, and to find out the difference between “ability” as a genetic tool and intelligent behavior far from genetic influence (pressure?). Animals are able to behave independent without any manipulation – they act by fun, they act as free ranging animals.  相似文献   

8.
Genus Atractylodes (Fam. Compositae) is the main source of two important Chinese traditional drugs, “Baizhu”and “Cangzhu”, both being long used as a stomachic. After a general survey and taxonomical study, it has been found that “Baizhu” was only derived from A. macrocephala Koidz. (A. ovata auct. Fl. Orient. Asiat. non A. P. DC.), while “Cangzhu” were mainly from A. lancea (Thunb.) DC. and A. lancea DC. var. chinensis Kitam. Comparison of the components in the rhizomes of Chinese Atractylodes has been made by TLC and GLC. The results have shown to be in accordance with their morphological features and pharmaceutical merits. “Baizhu”, A. macrocephala, with its leave pinnately incised, is characterized by the presence of rich atractylon and absence or lack of atractylodin. As for “Cangzhu”, A. lancea and A. lancea var. chinensis with their leave not incised or only lobed, are characterized by high contents of atractylodin, β-eudesmol and hinesol, but poor in atractylon. The above conclusion may be of value to both the classification and utilization of this group of Chinese medicinal plants.  相似文献   

9.
Within the methodology of phylogenetic systematics four hierarchic levels are distinguished: the “Central Claim” (to reconstruct phylogeny), methodoloical postulate (to conclude analysis with a purely dichotomous cladogram if ever possible), method (search for sister-group relationships by character analysis), and “Taxonomic Principle” (establishment of a classification reflecting merely the recognized genealoy). Certain limits of applicability and reliability of traditional phylogenetic systematics are specified: genealogy can only be analysed among taxa with perceptible evolutionary novelties; reticulated genealogy is not yet regarded; events other than cladogenetic ones cannot be recognised. Phylogenetic systematics is an independent method which has not been absorbed by any type of “pattern” or “transformed” cladism. Phylogenetic systematics relies on the theory of evolution, which does not lead into circularity, since phylogenetic systematics does not claim to prove or to explain evolution whatsoever.  相似文献   

10.
Over several decades, ethics and law have been applied to medical education and practice in a way that reflects the continuation during the twentieth century of the strong distinction between facts and values. We explain the development of applied ethics and applied medical law and report selected results that reflect this applied model from an empirical project examining doctors’ decisions on withdrawing/withholding treatment from patients who lack decision-making capacity. The model is critiqued, and an alternative “constitutive” model is supported on the basis that medicine, medical law, and medical ethics exemplify the inevitable entanglement of facts and values. The model requires that ethics and law be taught across the medical education curriculum and integrated with the basic and clinical sciences and that they be perceived as an integral component of medical evidence and practice. Law, in particular, would rank as equal in normative authority to the relevant clinical scientific “facts” of the case, with graduating doctors having as strong a basic command of each category as the other. The normalization of legal knowledge as part of the clinician’s evidence base to be utilized in practice may provide adequate consolation for clinicians who may initially resent further perceived incursions on their traditional independence and discretion.  相似文献   

11.
The Australian Weed Risk Assessment system (AWRA) is an effective pre-border weed-screening tool that has played an active role in preventing the introduction of alien weeds into Australia and has been utilized in several other countries worldwide. Here, we selected 131 species of naturalized exotic plants (including 76 species of given non-weeds and 55 species of given weeds) to evaluate the AWRA in China for the first time. The AWRA performed better for discriminating major weeds than non-weeds and minor weeds, as it correctly rejected 84% of major weeds and did not wrongly accept a major weed. Among non-weeds, 76% were correctly classified with the final outcome of “accept” and 7.9% were wrongly rejected by the AWRA. This system correctly rejected 56% of minor weeds but accepted only 2.8% of minor weeds. The remaining 23% of all alien plants tested were classified as “evaluate further” by the AWRA. The area under the ROC curve (AUC) was 0.944, suggesting that the AWRA would be highly efficient at discriminating alien plants in China. In addition, we compared the scores of seven attributes of the AWRA between prior plant categories and analyzed their correlation with weed status. The average score for each attribute differed significantly between the two prior categories (weed and non-weed), but the average scores of the attribute “undesirable traits” did not significantly differ between any two of the three categories (non-weeds, minor weeds, and major weeds). There was a significant positive correlation between the scores of each attribute of the AWRA and weed status. The correlation coefficient for “dispersal mechanisms” and weed status was the highest and that for “undesirable traits” was the lowest. We believe that the AWRA can serve as an important weed-screening tool for plant introduction management in China.  相似文献   

12.
Unwanted cats surrendered to nonhuman animal shelters are generally categorized as either “owned” or “stray.” This classification is misleading because “stray” cats may include many “semiowned” cats, for which people provide care but who are not perceived as being owned. This differentiation is important because effective strategies designed to reduce cat admissions to, and euthanasia rates in, shelters rely on accurate information about cat populations contributing to shelter intake; cat semiowners will likely respond to different strategies than people with no relationship with the cats they surrender. People surrendering cats to four Australian animal shelters were surveyed to identify factors associated with perception of ownership. Many self-classified nonowners had fed the cats they surrendered, often for a considerable period of time. The factor most strongly associated with ownership perception was an increasing association time with the cat. These findings confirm that enduring relationships between surrenderers and cats, consistent with cat semiownership, are common for cats surrendered to Australian animal shelters. This finding should be taken into account when planning education messages and cat population management strategies aimed at reducing cat admissions.  相似文献   

13.
The relationship between obesity and mental health was investigated, using data obtained from 1,660 persons selected as representative of 110,000 inhabitants of a residential area of New York City. In addition to confirming the previously noted relationship between obesity and age, preliminary analysis revealed a striking relationship between obesity and socioeconomic status of origin. The prevalence of obesity was 7 times higher among women reared in the lowest social class category as compared with those reared in the highest category. Scores made by the obese respondents on 9 mental health indices were compared with scores made by individuals of average weight. The obese respondents made more pathological scores on 8 of the 9 measures and on 3 of these the difference was statistically significant (“immaturity,” “rigidity,” and “suspiciousness”).  相似文献   

14.
15.
Abstract

In the model used in this study, father's occupation and education, the number of siblings, and the early intelligence level of the respondent are taken to be “predetermined” variables, with no assumption made as to causal order, with respect to later achieved status and to intelligence measured at maturity. Four successive dependent variables are educational attainment, intelligence at maturity, occupational achievement, and monetary earning. Results indicate that the ideal of equal educational opportunity is realized in the white population studied to the extent that progress through the school system is influenced at least as much by how bright you are as by “who” you are. However, the fact that the latter, indexed by measures of family size and status, does make a substantial difference in educational outcome, apart from its correlation with intelligence, is an indication that the ideal is far from being completely realized at this time.  相似文献   

16.
This study explored the prevalence of risk behaviors (excessive alcohol use, illegal drug use, heavy smoking, reduced sleep, overweight, underweight, sedentary behavior, high use of Internet/TV/videogames for reasons not related to school or work, and truancy), and their association with psychopathology and self‐destructive behaviors, in a sample of 12,395 adolescents recruited in randomly selected schools across 11 European countries. Latent class analysis identified three groups of adolescents: a low‐risk group (57.8%) including pupils with low or very low frequency of risk behaviors; a high‐risk group (13.2%) including pupils who scored high on all risk behaviors, and a third group (“invisible” risk, 29%) including pupils who were positive for high use of Internet/TV/videogames for reasons not related to school or work, sedentary behavior and reduced sleep. Pupils in the “invisible” risk group, compared with the high‐risk group, had a similar prevalence of suicidal thoughts (42.2% vs. 44%), anxiety (8% vs. 9.2%), subthreshold depression (33.2% vs. 34%) and depression (13.4% vs. 14.7%). The prevalence of suicide attempts was 5.9% in the “invisible” group, 10.1% in the high‐risk group and 1.7% in the low‐risk group. The prevalence of all risk behaviors increased with age and most of them were significantly more frequent among boys. Girls were significantly more likely to experience internalizing (emotional) psychiatric symptoms. The “invisible” group may represent an important new intervention target group for potentially reducing psychopathology and other untoward outcomes in adolescence, including suicidal behavior.  相似文献   

17.

Background  

Microarray experiments are becoming a powerful tool for clinical diagnosis, as they have the potential to discover gene expression patterns that are characteristic for a particular disease. To date, this problem has received most attention in the context of cancer research, especially in tumor classification. Various feature selection methods and classifier design strategies also have been generally used and compared. However, most published articles on tumor classification have applied a certain technique to a certain dataset, and recently several researchers compared these techniques based on several public datasets. But, it has been verified that differently selected features reflect different aspects of the dataset and some selected features can obtain better solutions on some certain problems. At the same time, faced with a large amount of microarray data with little knowledge, it is difficult to find the intrinsic characteristics using traditional methods. In this paper, we attempt to introduce a combinational feature selection method in conjunction with ensemble neural networks to generally improve the accuracy and robustness of sample classification.  相似文献   

18.
目的:探索传统教学模式结合网络云交互技术在外科实践教学中的应用效果。方法:于我校2011级五年制临床医学专业本科生中选取76人,随机平均分为两组,分别采取单纯传统大课教学模式、传统教学结合网络云交互技术教学模式;课程结束后进行闭卷理论考试和实践操作考试,综合两项成绩进行评定。同时向两组学员发放调查问卷,以此评价使用网络云交互技术辅助教学的效果。结果:采取传统教学结合网络云交互技术教学模式组的成绩优于采取单纯传统教学模式组,两组成绩差异具有统计学意义(P0.05)。结论:在传统教学模式的基础上添加网络云交互技术更能激发学生的学习兴趣,大大提高了学习效率,更有利于本科生外科实践的教学以及教学资源的整合及教学档案的建立。  相似文献   

19.
Abstract

Metaphors, such as those used in the title of this article, are often useful for the comprehension of specialised topics in plant biology. A brief attempt is made to elucidate one of these metaphors, plant “intelligence”, as it relates to the plastic responses of roots and root systems to their environment. Tropisms and nastic movements of root apices are two expressions of an inherent plasticity of form exhibited by roots. In soil, roots are exposed to multiple stimuli, many of which can potentially elicit such movements. Hence, a key question is how roots respond to and process the different stimuli which simultaneously reach their surfaces. Assuming that roots always use the same site along their length to express their movement responses, and that they also use an auxin‐based information‐transduction pathway, the most evident choices for the processing of stimuli are that roots either prioritise the various incoming stimuli and respond only to the strongest or they amalgamate stimuli and mount an averaged compromise response to all of them. The proposal that plants may be “intelligent”, especially in respect to their plastic growth responses, is one that draws upon knowledge of this faculty from animal biology. Also implied is that plants and animals are sufficiently similar to share usage of this term “intelligence”. But an alternative view is that plants and animals are sufficiently different and so intelligence is an unfitting term. Following the line of enquiry into creative evolution initiated by Henri Bergson, plants can be viewed differently to animals. The tendency of plants is towards instinctive behaviour rather than intelligent behaviour.  相似文献   

20.
Protein engineering experiments have recently yielded hyperstable variants of the thermolysin-like protease from Bacillus stearothermophilus (TLP-ste). These variants contain mutations suggested by comparison of TLP-ste with its more thermostable counterpart thermolysin, as well as rationally designed mutations. The key to the successful stabilization strategy was the identification of a “weak” region that is involved in early unfolding events (“unfolding region”). Mutations in this region had large effects on stability, whereas mutations in other parts of the protein generally had minor effects. The mutational strategies that were used as well as characteristics of the engineered hyperstable biocatalysts are reviewed below.  相似文献   

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