Abstract Fensham (2002) proposes that we modify the composition of those involved in the political power struggle ('educo‐politics') over who determines the science curriculum. He suggests that ‘societal experts’ are better situated than academic scientists to decide what knowledge is worth having, although his plan for curriculum development includes academic scientists deciding what science content supports the issues initially identified by societal experts. However, Fensham's proposal lacks the educo‐politics needed to counter the customary devious educo‐politics we have come to expect from those who support the status quo—particularly some academic scientists. Fensham's proposal gives academic scientists unnecessary political advantage. School science for an informed citizenry will continue to be marginalized if its supporters do not win at educo‐politics. Curriculum developers have few universal principles of action to follow other than Sgt. Jablonski's (of Hill Street Blues) ’Do it to them before they do it to you.’ This article clarifies some of these Jablonskian counter‐educo‐politics. 相似文献
Self-efficacy is an individual’s belief about her ability to perform well in a given situation. Because self-efficacious students are effective learners, endowing intelligent tutoring systems with the ability to diagnose self-efficacy could lead to improved pedagogy. Self-efficacy is influenced by (and influences) affective state. Thus, physiological data might be used to predict a student’s level of self-efficacy. This article investigates an inductive approach to automatically constructing models of self-efficacy that can be used at runtime to inform pedagogical decisions. It reports on two complementary empirical studies. In the first study, two families of self-efficacy models were induced: a static self-efficacy model, learned solely from pre-test (non-intrusively collected) data, and a dynamic self-efficacy model, learned from both pre-test data as well as runtime physiological data collected with a biofeedback apparatus. In the second empirical study, a similar experimental design was applied to an interactive narrative-centered learning environment. Self-efficacy models were induced from combinations of static and dynamic information, including pre-test data, physiological data, and observations of student behavior in the learning environment. The highest performing induced naïve Bayes models correctly classified 85.2% of instances in the first empirical study and 82.1% of instances in the second empirical study. The highest performing decision tree models correctly classified 86.9% of instances in the first study and 87.3% of instances in the second study. 相似文献
A total of 436 Staphylococcus aureus bacteremia strains isolated between 1959 and 1990 were tested for the production of toxic shock syndrome toxin-1 (TSST-1) by a semiquantitative reversed passive latex agglutination test. TSST-1 production was found in 147/260 (57%) of phage group I strains, excluding the "80" complex, and in 17/176 (10%) of non-group I strains. Strains of the 52, 52A, 80, 81 complex ("80" complex), constituting a subgroup of group I, did not have the same high frequency of TSST-1 production as the rest of group I strains (4% versus 57%). The "80" complex has almost disappeared in Denmark. TSST-1 production was found with the same high frequency among group I strains from the beginning (1959) and throughout the observation period. The TSST-1 production was associated with the phages 29 and/or 52, which in turn lysed 95% of group I strains. The TSST-1 production was quantitatively greater in the phage group I strains than in the non-group I strains. TSST-1 production of the bacteremia strains was not correlated to the clinical parameters: mortality, age, gender, bacterial focus, underlying diseases, or whether the infection was hospital or community acquired. 相似文献
Malunions of the hand present a challenging problem to the orthopaedic surgeon. Angular and rotational deformities, and shortening and articular incongruity, can lead to significant functional impairment or dysesthetic appearance. The prevention of malunion should remain a primary goal. When displaced fractures of the metacarpals or phalanges present within the first or second weeks, properly performed closed or open reduction with percutaneous pinning or internal fixation are excellent options with predictable results. Malaligned fractures that present later frequently cannot be readily reduced. Once fully united, treatment options have included corrective osteotomy if function is significantly impaired or if appearance is objectionable; for patients who are not suitable for surgery for medical or other reasons, or for whom appearance is acceptable, intensive occupational therapy to maximize function may yield sufficiently serviceable clinical results. During the past several years, the senior author (BL) has chosen to be more proactive in the prevention of malunions of the hand. In the authors' experience, results of aggressive surgical treatment of subacute, malaligned fractures in selected patients have produced results comparable with or superior to those reported for later reconstructive procedures. With the proliferation of managed care, there has been an increasing frequency of delayed referral patterns for fracture treatment by hand specialists. Definitive treatment of these "impending malunions" is preferable to passive treatment delay and secondary reconstructive procedures, offering both earlier correction of alignment and earlier opportunity for return of function. 相似文献
Man-mounted miniature recording equipment has been used to measure the electroacoustic conditions obtaining in cockpits of aircraft and at the pilot's ear during operational sorties in the Royal Air Force. Although this paper considers the measurements taken that relate to the total noise exposure (noise dose) received by aircrew, the results apply equally to anyone who is exposed to high noise and requires communications.
Comparison of the noise at the ear with the cockpit noise gave a measure of headgear attenuation which was used to adjust a 1/3-octave filter. Playing cockpit noise tapes through this filter to a noise dose meter gave the noise dose that would have been experienced had there been no communications signals. The results showed that the communications signals at the ear, averaging 40% of the sortie time, are a major contributor to the total dose, and, without the signals, the dose averaged about 6 dB less. In view of the Health and Safety at Work Act, 1974, employers should be aware of the additional dose to which employees are exposed because of communications.
A method for the prediction of noise dose is proposed where communication takes place in a noisy environment. 相似文献
The impact of HIV-related parental death on 414 adolescents was examined over a period of 6 years. The adjustment of bereaved adolescents was compared over 4 time periods relative to parental death and was also compared with the adjustment of nonbereaved adolescents. Bereaved adolescents had significantly more emotional distress, negative life events, and contact with the criminal justice system than nonbereaved youths; these behaviors did not remain significantly higher after parental death. Depressive symptoms and passive problem solving increased soon after parental death, as compared with nonbereaved adolescents. One year subsequent to parental death, depression and passive problem solving were similar to the levels of nonbereaved peers. Only sexual risk behaviors increased following parental death. These results suggest the importance of early family intervention soon after parental HIV diagnosis, prior to parental death, and sustained over time. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
An enzyme-linked immunosorbent assay (ELISA) for Neospora caninum antibodies was automated with a robotic workstation, the Beckman Coulter Biomek 2000, to screen 200 bovine sera. Comparing these results with manually run ELISA data, a 95.92% agreement (K = 0.9592) between the two assays was obtained. The automated assay was specific and sensitive with excellent positive and negative predictive values. The results were repeatable and reproducible. The automation flexibility was high and the operation complexity was minimal. High-throughput screening (HTS) for bovine antibodies to Neospora caninum was achieved. The assay was developed according to the internationally recognized ISO17025 standard requirements. 相似文献
This paper proposes an ultrasonic measurement model that can predict the pulse-echo signals from a flat-bottom hole in an isotropic, homogeneous solid specimen immersed in water in a computationally efficient manner. To develop such a model, a measurement model approach is adopted based on two important assumptions: the paraxial approximation for the transducer beam and the small flaw assumption for the flat-bottom hole. The modular model that results from these two assumptions contains three terms: a diffraction correction term, a far-field scattering amplitude term and a system efficiency factor term. The diffraction correction is defined based on a multi-Gaussian beam model which allows the rapid evaluation of the wave field incident on the hole. The far-field scattering amplitude of the flat-bottom hole is obtained using the Kirchhoff approximation together with the small flaw assumption. The system efficiency factor is determined by deconvolution of an experimental front surface reflection signal by a reference reflector model. Here, the contribution of each of these three terms to the overall measurement model are described in detail and the accuracy of the proposed model is verified by the comparison of the model-based predictions to experiments. 相似文献
During the 1989 Loma Prieta earthquake the Pajaro River levees near Watsonville, Calif., spread laterally at multiple locations. Four of these locations are discussed in this paper. At one location, an industrial facility was also damaged and a dispute arose as to whether lateral spreading of the adjacent levee was the cause. Stability analyses were made of the industrial site for conditions before, during, and after the earthquake. To confirm the findings, analyses were also made of three other nearby locations where the actual deformation was documented and the subsurface conditions are well defined. The calculated levee deformations at the four locations are quite consistent with the observed movements (up to 60 cm). This experience provides increased confidence in the methods of analysis described, for the characterized subsurface conditions, and the range of ground motions experienced. Additional analyses made using the more recently developed multilinear regression lateral-spreading model (e.g., Youd et al. in 1999) yielded inconsistent results. 相似文献
Lipid structural diversity strongly affects biomembrane chemico-physical and structural properties in addition to membrane-associated events. At high concentrations, cholesterol increases membrane order and rigidity, while polyunsaturated lipids are reported to increase disorder and flexibility. How these different tendencies balance in composite bilayers is still controversial. In this study, electron paramagnetic resonance spectroscopy, small angle neutron scattering, and neutron reflectivity were used to investigate the structural properties of cholesterol-containing lipid bilayers in the fluid state with increasing amounts of polyunsaturated omega-3 lipids. Either the hybrid 1-stearoyl-2-docosahexaenoyl-sn-glycero-3-phosphocholine or the symmetric 1,2-docosahexaenoyl-sn-glycero-3-phosphocholine were added to the mixture of the naturally abundant 1-palmitoyl-2-oleyl-sn-glycero-3-phosphocholine and cholesterol. Our results indicate that the hybrid and the symmetric omega-3 phospholipids affect the microscopic organization of lipid bilayers differently. Cholesterol does not segregate from polyunsaturated phospholipids and, through interactions with them, is able to suppress the formation of non-lamellar structures induced by the symmetric polyunsaturated lipid. However, this order/disorder balance leads to a bilayer whose structural organization cannot be ascribed to either a liquid ordered or to a canonical liquid disordered phase, in that it displays a very loose packing of the intermediate segments of lipid chains. 相似文献