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991.
This paper is an introduction to the following five articles, that have been conceived together as one chapter on habitability consideration for outer space habitations. Those contributions are made from authors in different fields, cultures and countries working with the Extreme-Design.eu research group. Projects, theories and requirements are referred to the context of outer space habitats, where for the love of knowledge, human beings are living under extreme condition. The group purpose is to apply holistic approach (using both scientific and humanity discipines) towards space habitat design to support human cultural experience and improve technical reliability. Space Anthropology, Space Design, Space Art and Space Psychology are the established disciplines here considered to have a bearing on astronaut reliability. With multidisciplinary contributions, natural design philosophy- and human-centred design, these papers aim of collecting a range of solutions and innovative ideas on how to increase habitability in space.  相似文献   
992.
The present study focuses on the design and development of an instructional approach to develop oral presentation skills. The theoretical base builds on the social cognitive perspective, and self-regulated learning. The aim of the study is to investigate whether the design of a multimedia-based instructional format - comprising of a standardised multimedia instruction, practical activities and feedback - will enhance oral presentation skills. In the study, the differential effect of three ‘modes of feedback’ on performance has been researched. The results reveal that oral presentation skills did improve significantly after the instruction. The multimedia nature of the design was favoured by all participants. In contrast, no significant impact of feedback was found. Nevertheless, feedback proved to be a useful process that was highly welcomed by participants.  相似文献   
993.
As the micro technology field expands, the need of simple and standardized procedures to precisely evaluate device functionality, realibility and quality of micro electro mechanical systems devices increases. In this paper the application of two empirical methods suitable for the static and the dynamic characterization of micrometersized structures is proposed. The first methodology is based on capacitance measurements and finds simple application in case of comb-finger actuated devices. The second one is based on the Doppler phenomenon combined with laser optical interferometry allowing the characterization of a wide range of structures. The methodologies are applied to a reliability test structure specifically designed at STMicroelectronics for studying the fatigue behaviour of the structural material involved in the fabrication of their commercial products. This case of study highlights how the techniques may be coupled to usual design approaches for completing and verifying the information given by theory and simulations; thus improving the entire development cycle.  相似文献   
994.
995.
Ant queen pheromones (QPs) have long been known to affect colony functioning. In many species, QPs affect important reproductive functions such as diploid larvae sexualization and egg-laying by workers, unmated queens (gynes), or other queens. Until the 1990s, these effects were generally viewed to be the result of queen manipulation through the use of coercive or dishonest signals. However, in their seminal 1993 paper, Keller and Nonacs challenged this idea, suggesting that QPs had evolved as honest signals that informed workers and other colony members of the queen’s presence and reproductive state. This paper has greatly influenced the study of ant QPs and inspired numerous attempts to identify fertility-related compounds and test their physiological and behavioral effects. In the present article, we review the literature on ant QPs in various contexts and pay special attention to the role of cuticular hydrocarbons (CHCs). Although the controversy generated by Keller and Nonacs’ (Anim Behav 45:787–794, 1993) paper is currently less intensively debated, there is still no clear evidence which allows the rejection of the queen control hypothesis in favor of the queen signal hypothesis. We argue that important questions remain regarding the mode of action of QPs, and their targets which may help understanding their evolution.  相似文献   
996.
Recently published data suggest that the assessment of LDL subfraction profiles may contribute to the determination of the cardiovascular risk. In this study, we tested the ability of various metabolic parameters to estimate the presence or the preponderance of small, dense LDL particles (sdLDL). One hundred and fifty individuals attending the Outpatient Clinics of the University Hospital of Ioannina for suspected metabolic abnormalities were included in the study. Individuals were excluded if they were found to be diabetic or if they had a history of cardiovascular disease. Patients with thyroid dysfunction, liver or kidney diseases as well as those receiving drugs that may interfere with lipids or glucose metabolism were also excluded from the study. The ability of the various parameters to identify individuals with pattern B LDL phenotype or, alternatively, with measurable quantities of sdLDL particles was tested with the calculation of the areas under the ROC curves. The ratio of triglycerides to HDL-C was the best predictor of the presence of the pattern B LDL phenotype. Nevertheless, when the variable of interest was the presence of measurable quantities of sdLDL subfractions, the ratio of apoB to apoAI had the best predictive ability. In conclusion the ratios of apoB to apoAI and of triglycerides to HDL-C can reliably predict the presence of measurable quantities of sdLDL particles and of the pattern B LDL phenotype, respectively. However, since the quantitative determination of sdLDL concentrations may contribute to the determination of the cardiovascular risk, whereas the role of the LDL particle size remains controversial, apoB to apoAI ratio could provide more valuable information compared to markers that simply predict the presence of the pattern B LDL phenotype.  相似文献   
997.
The aims were to compare the mucoadhesivity, controlled release properties, and release mechanisms of several polymeric systems of propranolol buccal tablets and to propose polymer(s) for formulation optimization. Mucoadhesivity differences in the polymer ranking between compacts and tablets were found. Mathematical models that best described the matrices were power law or a combination of the power law and Hopfenberg models. Poly acrylic acid (PAA), carboxymethyl cellulose (CMC), and poly ethylene glycol (PEG) in combination, were identified as suitable polymers for formulation optimization of a multipolymeric propranolol buccal tablet. Artificial neural networks were employed as a confirmatory approach to explicate that the selected polymers, in particular PAA, produced the most significant effect on the mean dissolution time and mucoadhesivity.  相似文献   
998.
Titanium nitride (TiN) coating has been proposed as an adjunctive surface treatment aimed to increase the physico-mechanical and aesthetic properties of dental implants. In this study we investigated the biological response of primary human bone marrow stromal cells (BMSC) to TiN-coated sandblasted (TiN-SB) compared to uncoated sandblasted (SB) surfaces. SB and TiN-SB disks were qualitatively and quantitatively analyzed by atomic force microscopy. BMSC were obtained from healthy donors and their adhesion and proliferation on the titanium disks were evaluated by scanning electron microscopy and viability assay. The osteoblastic differentiation, in terms of alkaline phosphatase activity, osteocalcin synthesis, and extracellular mineralization, was assessed by specific immunoenzymatic or spectrophotometric assays. No difference (P > 0.05) between TiN-SB and SB disks was found in terms of any of the investigated parameters. TiN-coating showed to maintain the topographical characteristics of sandblasted titanium surfaces and their biological affinity toward bone precursors.  相似文献   
999.
Oligophenylenevinylene (OPV) units containing a hydroxyl polar head group and different dendritic poly(benzyl ether) branches bearing aliphatic chains (n-propyl and n-dodecyl) have been synthesized. The obtained dendrimers were characterized by 1H and 13C NMR, FTIR and absorption spectroscopies. Optical properties of the dendrimers have been studied in toluene and dichloromethane solutions. Changes in the maximum absorption wavelength were observed for the dendrimers OPV core. Increasing the dendron branches generation gave rise to a hypsochromic shift of the maximum absorption band of the OPV core. The ability of all dendrimers to form Langmuir films at the air-water interface was also investigated; the obtained films were characterized by surface pressure versus molecular area isotherms, and by compression-expansion cycles (hysteresis curves). All dendrimers were able to form stable Langmuir monolayers in the air-water interface, and exhibited a good reversible behavior upon successive compression/expansion cycles. The terminal alkyl chains length of the dendritic branches has a remarkable influence on the packing of highest generation dendrimers in the monolayers. These dendrimers can be promising prospects for the preparation of Langmuir-Blodgett films, in view of optical and electronic potential applications.  相似文献   
1000.
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