Photonic Structures in Biology: A Possible Blueprint for Nanotechnology

Nature has had millions of years to optimize photonic crystals - an endeavour mankind only really began in the 1980s. Often, we attempt to mimic and expand upon nature’s designs in creating photonic structures that meet our technology-driven needs. While this strategy can be fruitful in fabricating novel architectures, one has to keep in mind that nature designed and optimized these structures for specific applications (e.g., colouration, camouflaging, signalling), but certainly not for use in photonic chips and optical circuits. To take full advantage of biological structures as blueprints for nanotechnology, it is important to understand the purpose and development of natural structural colours. In this review, we will discuss important aspects of the design, formation and evolution of the structures embedded in beetle exoskeletons that are responsible for their striking colouration. In particular, we will focus on the purpose of structural colours for camouflaging, mimicry and signalling. We will discuss their evolutionary and ecological development and compare the development of beetles with and without structural colours. Examples of non-colour-related structural functionalities will also be introduced and briefly discussed. Finally, a brief overview of nature’s synthesis strategies for these highly evolved structures will be given, with particular focus on membrane assembly

The effect of ratio and interval training on Pavlovian-instrumental transfer in mice.

Conditional stimuli (CS) that are paired with reward can be used to motivate instrumental responses. This process is called Pavlovian-instrumental transfer (PIT). A recent study in rats suggested that habitual responses are particularly sensitive to the motivational effects of reward cues. The current experiments examined this idea using ratio and interval training in mice. Two groups of animals were trained to lever press for food pellets that were delivered on random ratio or random interval schedules. Devaluation tests revealed that interval training led to habitual responding while ratio training produced goal-directed actions. The presentation of CSs paired with reward led to positive transfer in both groups, however, the size of this effect was much larger in mice that were trained on interval schedules. This result suggests that habitual responses are more sensitive to the motivational influence of reward cues than goal-directed actions. The implications for neurobiological models of motivation and drug seeking behaviors are discussed

Influence of Restaurant Reviews Upon Consumers

It is generally believed that restaurant reviews can influence consumers\u27 decisions in choosing a restaurant. A survey administered to a sample of 420 college faculty and staff members suggests that while most restaurant patrons may read reviews, they are not used as the sole selection criterion. Recommendations of friends, the restaurant\u27s current reputation, and perceived value may have greater influence upon the choice than does a re- view. The authors discuss the implications of both favorable and unfavorable reviews

Standardized patient outcomes trial (SPOT) in neurology

Background: The neurologic examination is a challenging component of the physical examination for medical students. In response, primarily based on expert consensus, medical schools have supplemented their curricula with standardized patient (SP) sessions that are focused on the neurologic examination. Hypothesis-driven quantitative data are needed to justify the further use of this resource-intensive educational modality, specifically regarding whether using SPs to teach the neurological examination effects a long-term benefit on the application of neurological examination skills. Methods: This study is a cross-sectional analysis of prospectively collected data from medical students at Weill Cornell Medical College. The control group (n=129) received the standard curriculum. The intervention group (n=58) received the standard curriculum and an additional SP session focused on the neurologic examination during the second year of medical school. Student performance on the neurologic examination was assessed in the control and intervention groups via an OSCE administered during the fourth year of medical school. A Neurologic Physical Exam (NPE) score of 0.0 to 6.0 was calculated for each student based on a neurologic examination checklist completed by the SPs during the OSCE. Composite NPE scores in the control and intervention groups were compared with the unpaired t-test. Results: In the fourth year OSCE, composite NPE scores in the intervention group (3.5±1.1) were statistically significantly greater than those in the control group (2.2±1.1) (p<0.0001). Conclusions: SP sessions are an effective tool for teaching the neurologic examination. We determined that a single, structured SP session conducted as an adjunct to our traditional lectures and small groups is associated with a statistically significant improvement in student performance measured 2 years after the session

Case Report Acanthosis Nigricans Associated with an Adrenocortical Tumor in a Pediatric Patient

Malignant acanthosis nigricans (AN) is a rare paraneoplastic syndrome seen primarily in adults with an underlying diagnosis of gastrointestinal adenocarcinoma. Malignant AN is characterized by hyperpigmentation and velvety hyperplasia of the epidermis. This condition is generally not associated with tumors in pediatric populations or in the adrenal gland. We present a case of malignant AN in a pediatric patient with a nonmalignant, functional adrenocortical tumor

Quantitative estimate of the paleo-Agulhas leakage

The Indian-Atlantic water exchange south of Africa (Agulhas leakage) is a key component of the global ocean circulation. No quantitative estimation of the paleo-Agulhas leakage exists. We quantify the variability in interocean exchange over the past 640,000 years, using planktic foraminiferal assemblage data from two marine sediment records to define an Agulhas leakage efficiency index. We confirm the validity of our new approach with a numerical ocean model that realistically simulates the modern Agulhas leakage changes. Our results suggest that, during the past several glacial-interglacial cycles, the Agulhas leakage varied by ~10 sverdrup and more during major climatic transitions. This lends strong credence to the hypothesis that modifications in the leakage played a key role in changing the overturning circulation to full strength mode. Our results are instrumental for validating and quantifying the contribution of the Indian-Atlantic water leakage to the global climate changes

Computer-supported collaborative learning with digital video cases in teacher education: the impact of teaching experience on knowledge convergence

Case-based learning is ascribed high potential with respect to the education of pre-service teachers as well as the further education of experienced in-service teachers, as it can provide opportunities for the application of professional knowledge to authentic classroom situations. In addition to the application and acquisition of knowledge, the aspect of knowledge convergence (i.e., increasing similarity of collaborative learners with respect to their knowledge) should be taken into account when homogeneous benefits are desired for all participants of a case-based training. A field study with 29 pre-service teachers and 24 in-service teachers from adult education was conducted to examine effects of different levels of teaching experience on knowledge application, knowledge acquisition, and knowledge convergence in a computer-supported collaborative case-based learning environment. An innovative approach to measuring knowledge convergence was introduced, using the positions of annotations (i.e., flags placed on the timeline of the case video) made by learners during their case analyses as an indicator of their shared focus of attention. This measure was found to positively correlate with the application and acquisition of professional knowledge. Teaching experience affected both processes and outcomes of case-based learning, suggesting different means of instructional support for pre-service and in-service teachers

A Study of Vocational Education in a Comprehensive High School with Recommendations for Vocational Education and Educational Specifications for Industrial Education at East High School, Salt Lake City, Utah

This study resulted from the selection of East High School in Salt Lake City to participate in a State Sponsored comprehensive high school project entitled Project Success. The primary emphasis of the project was to encourage the development of vocational education as part of the high school curriculum. The purpose of this study was to assist the Salt Lake City School District and East High School in the planning of vocational education programs and facilities by providing a rationale for vocational education within a comprehensive high school, making specific recommendations for vocational education programs, and by writing educational specifications for the programs recommended for Industrial Education. Data were gathered through a review of the literature, an opinionnaire mailed to graduates of East High School, a survey of local employers, and conferences with District planners and East High School personnel. The recommendations resulting from this study were present ed in the form of nine mandates for a comprehensive high school, followed by fourteen criteria for the vocational education programs at East High School. A major recommendation was that East High School establish a Center for Bifocal Vocational Education, having vocational education programs that give as much emphasis on developing the personal traits and attitudes of the students as they do on developing specific job skills. The phrase bifocal vocational education was coined to stress this dual focus or dual emphasis. A Department of Personal Development was suggested that would be primarily concerned with developing the employability traits and attitudes that are deemed as important as the specific job skills. Specific occupational clusters were suggest en as a basis for the recommended vocational education. These are Industrial Occupations , Business Occupations, and Home and Service Occupations. A further recommendation was for expansion of the vocational education to include the entire Salt Lake City area through cooperative work experience and work study programs. Educational specifications For the recommended industrial education programs were written and presented to the district for use as guide to planning additional facilities