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1.
Intended learning outcomes (ILOs) indicate what learners will be able to achieve after they are taught. Traditionally, ILOs are expressed as plain text or unstructured documents. What if all ILOs of a specific course of study can be conceptualized through a structured diagrammatic technique? It was hypothesized that learners can benefit from this conceptualization in learning, especially in self‐regulated learning. The aim of this study was to investigate whether the ILOs represented in unstructured or structured formats can facilitate learners to identify learning paths. The results revealed that the mean ratings of all learning paths were statistically significantly higher with structured ILOs.  相似文献   
2.
Tumor suppressor genes such as p53 contribute to the oncogenic process via loss-of-function mechanisms such as genetic mutation or complex formation with other cellular or viral proteins. p53 is mutated in approximately 50% of human tumors and has an important role in the genesis or progression of both colorectal and hepatocellular cancers. Colorectal cancer is leading cause of cancer mortality in the United States, whereas hepatocellular cancer is the leading worldwide cause of cancer death; the liver is a primary site of morbidity in both diseases. Because systemic tumor suppressor gene therapy is currently not feasible, we have chosen to develop a regional form of such therapy directed at primary or metastatic liver neoplasms. Gene replacement therapy with p53 is a promising new strategy to treat advanced human cancers.  相似文献   
3.
Being perceptive is a trait highly valued in scientific and engineering professions. What a scientist or engineer notices while considering a problem, evaluating alternatives, or interpreting data has a profound impact on how a problem is viewed and solved. This paper focuses on processes we believe underlie being perceptive: firstly, preparation—becoming attuned to salient or important features; secondly, assimilation-detection and exploration of patterns (invariants) as well as anomalies; and thirdly, strategic control-heuristic strategies for exploring the implications of what has been observed. These processes play an integral role in characteristic activities within creative design, including problem reformulation, the emergence of properties and constraints on the solution, and the ability to incorporate into the design experimental feedback from the environment and from experiences with prototypes and previous designs. The paper presents a computational model incorporating these ideas, implemented in a system called IMPROVISER.  相似文献   
4.
While mitochondrial sequences can be used to probe the time and place of the mitochondrial 'Eve,' nuclear genes can be used to ask a slightly different question: when did humans (members of the genus Homo) or their hominid precursors (the hominids) first leave Africa and fan out over Asia and Europe? If they did so recently, it seems likely that there was a recent African origin of our species, Homo sapiens, rather than multiple origins in various parts of the Old World. A recent paper uses minisatellite data to make the argument that the departure from Africa happened very recently indeed. An alternative explanation for the data is that there was no single and irreversible departure from Africa, but that some peoples migrated back and forth between Africa and the rest of the Old World over the last few tens of thousands of years. For this and other reasons, putting a single date on the farewell to Africa remains problematical.  相似文献   
5.
A multilayer background modeling technique is presented for video surveillance. Rather than simply classifying all features in a scene as either dynamically moving foreground or long-lasting, stationary background, a temporal model is used to place each scene object in time relative to each other. Foreground objects that become stationary are registered as layers on top of the background layer. In this process of layer formation, the algorithm deals with ”fake objects” created by moved background, and noise created by dynamic background and moving foreground objects. Objects that leave the scene are removed based on the occlusion reasoning among layers. The technique allows us to understand and visualize a scene with multiple objects entering, leaving, and occluding each other at different points in time. This scene understanding leads to a richer representation of temporal scene events than traditional foreground/background segmentation. The technique builds on a low-cost background modeling technique that makes it suitable for embedded, real-time platforms.  相似文献   
6.
The days ahead     
Noseworthy E  Gladding M  Wills J  Tindall C  Placides D  Sanford T  Sims L  Marshall D  Jones RM  Bayne D 《Food management》1991,26(7):118-20, 122, 124 passim
How are government controls affecting healthcare foodservices?Are growing elderly & outpatient populations changing foodservices' missions. What are the hottest trends? As members of the American Society for Hospital Food Service Administrators prepared for their annual meeting in Orlando, FM queried 11 Southeastern directors to learn their most pressing concerns & how they are positioning their departments for the future.  相似文献   
7.
Real-time underwater visualization has been extremely slow to develop within the offshore industry and has generally been limited to 2D representations of vessel positions on digital charts. Only recently have marine industries realized the potential of 3D real-time virtual environments and visualization systems for effective management planning and real-time situation awareness. We describe a real-time visualization of the clean-up of a former US Naval Submarine Base, located in Holy Loch, Scotland. Our Whole-Field Modeling System has provided an accurate real-time visualization of numerous varying parameters such as remotely operated vehicles (ROVs), cranes, barges, grabs, magnets, and detailed seabed topography. The system improved the field staffs' spatial and temporal awareness and facilitated decision making within the complex offshore working environment. A side bar discusses another application, offshore diamond mining  相似文献   
8.
Ion beam extraction from two different ion sources with single aperture triode extraction columns was simulated with the particle beam transport codes PBGUNS and IGUN. For each ion source, the simulation results are compared to experimental data generated on well-equipped test stands. Both codes reproduced the qualitative behavior of the extracted ion beams to incremental and scaled changes to the extraction electrode geometry observed on the test stands. Numerical values of optimum beam currents and beam emittance generated by the simulations also agree well with test stand data.  相似文献   
9.
Saudi universities have at their disposal a huge number of low cost IT resources to aid in teaching, research and learning. By migrating to cloud services, Saudi universities will be moving data and programs from local servers to the internet, thereby providing users with the ability to access and share information at any time from multiple devices. The migration to cloud-based IT resources is not yet widespread in Saudi universities due to several challenges including security, legal policies and implementation. At present, there is lack of research and guidance for Saudi universities on how to overcome these challenges and how contextual factors can influence the successful migration to the educational clouds.This research presents a framework for the successful migration to cloud technology in the Saudi Arabian universities. In this research, a set of key critical success factors (CSFs) were identified by synthesizing components from studies concerned with the migration of cloud for higher education and factors identified from the successful implementation of WBL (Web Based Learning) and ERP (Enterprise Resource Planning) on higher education in Saudi Arabia. Based on this knowledge, the proposed framework was evaluated via expert review and a survey by IT specialists from the Saudi universities. The initial CSFs were updated based on the expert reviews and the results were analysed. Based on the findings at this stage, additional CSFs were added to the framework as suggested by the experts. Subsequently, in order to confirm the reviewed CSFs, additional investigation via a structured online questionnaire was conducted and the outcome was analysed via one-sample t-test with the data integrity analysed via Cronbach’s alpha. The outcome indicated the majority of CSFs to be statistically significant except the Physical Location CSF. Potential future study and contributions are discussed.  相似文献   
10.
The role of aminoacyl-tRNA synthetases (aaRS) in the emergence and evolution of genetic coding poses challenging questions concerning their provenance. We seek evidence about their ancestry from curated structure-based multiple sequence alignments of a structurally invariant “scaffold” shared by all 10 canonical Class I aaRS. Three uncorrelated phylogenetic metrics—mutation frequency, its uniformity, and row-by-row cladistic congruence—imply that the Class I scaffold is a mosaic assembled from successive genetic sources. Metrics for different modules vary in accordance with their presumed functionality. Sequences derived from the ATP– and amino acid– binding sites exhibit specific two-way coupling to those derived from Connecting Peptide 1, a third module whose metrics suggest later acquisition. The data help validate: (i) experimental fragmentations of the canonical Class I structure into three partitions that retain catalytic activities in proportion to their length; and (ii) evidence that the ancestral Class I aaRS gene also encoded a Class II ancestor in frame on the opposite strand. A 46-residue Class I “protozyme” roots the Class I tree prior to the adaptive radiation of the Rossmann dinucleotide binding fold that refined substrate discrimination. Such rooting implies near simultaneous emergence of genetic coding and the origin of the proteome, resolving a conundrum posed by previous inferences that Class I aaRS evolved after the genetic code had been implemented in an RNA world. Further, pinpointing discontinuous enhancements of aaRS fidelity establishes a timeline for the growth of coding from a binary amino acid alphabet.  相似文献   
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