Skull base imaging, anatomy, pathology and protocols

The skull base is the major bony and soft tissue interface for the intracranial and extracranial compartments. Its anatomy is complex, containing multiple traversing foramina that act as conduits for various neurovascular structures. The optimum imaging modality depends on the specific diagnostic question and area of interest; both CT and MR have complementary roles. This article focuses on the applied compartmental anatomy of the skull base and specific imaging protocols, and discusses the range of pathologies that neurologists will encounter.

PRELIMINARY STUDIES OF ANALYZING MISCONCEPTION AND SCIENTIFIC ARGUMENTATION USING DIAGNOSTIC QUESTION CLUSTERS (DQCS) OF MOLECULAR GENETICS CONCEPT

This study aimed to analyze the misconceptions and argumentation ability Biology educationstudents using diagnostic question clusters on the concept of molecular genetics. In addition,this study aims to look at the pattern of misconceptions tendencies and scientificargumentation ability of students accompanied by the factors supporting the occurrence ofmisconceptions and arguments student achievement levels. As this study focused on theconcept of molecular genetics which includes the concept of genes, chromosomes, DNA, andprotein synthesis. This research was conducted with the descriptive research method and thesample using purposive sampling techniques. The subjects were biology education students ofIslamic University of Sunan Gunung Djati Bandung who attended the lectures of genetics inthe academic year 2014/2015. The instrument used is a matter of diagnostic question clusters(DQCs) which covers a combined essay and multiple choice questions, learning observationsheet, and interview guidelines used to determine the factors that cause the occurrence ofmisconceptions and what degree of scientific argumentation ability students. The ability of thescientific arguments that will be analyzed is the ability to claim, warrant, backing, andrebutal (Toulmin, 1984).

Developing, evaluating, and refining an automatic generator of diagnostic multiple choice cloze questions to assess children's comprehension while reading

We describe the development, pilot-testing, refinement, and four evaluations of Diagnostic Question Generator (DQGen), which automatically generates multiple choice cloze (fill-in-the-blank) questions to test children's comprehension while reading a given text. Unlike previous methods, DQGen tests comprehension not only of an individual sentence but of the context preceding it. To test different aspects of comprehension, DQGen generates three types of distractors: ungrammatical distractors test syntax; nonsensical distractors test semantics; and locally plausible distractors test inter-sentential processing.(1)A pilot study of DQGen 2012 evaluated its overall questions and individual distractors, guiding its refinement into DQGen 2014.(2)Twenty-four elementary students generated 200 responses to multiple choice cloze questions that DQGen 2014 generated from forty-eight stories. In 130 of the responses, the child chose the correct answer. We define thedistractivenessof a distractor as the frequency with which students choose it over the correct answer. The incorrect responses were consistent with expected distractiveness: twenty-seven were plausible, twenty-two were nonsensical, fourteen were ungrammatical, and seven were null.(3)To compare DQGen 2014 against DQGen 2012, five human judges categorized candidate choices without knowing their intended type or whether they were the correct answer or a distractor generated by DQGen 2012 or DQGen 2014. The percentage of distractors categorized as their intended type was significantly higher for DQGen 2014.(4)We evaluated DQGen 2014 against human performance based on 1,486 similarly blind categorizations by twenty-seven judges of sixteen correct answers, forty-eight distractors generated by DQGen 2014, and 504 distractors authored by twenty-one humans. Surprisingly, DQGen 2014 did significantly better than humans at generating ungrammatical distractors and marginally better than humans at generating nonsensical distractors, albeit slightly worse at generating plausible distractors. Moreover, vetting DQGen 2014's output and writing distractors only when necessary would halve the time to write them all, and produce higher quality distractors.

The bias of the question posed: a diagnostic “invisible gorilla”

Posing a question can introduce a powerful bias into the diagnostic process. A clinical case is presented to demonstrate how a colleague’s diagnostic question can focus the clinicians’ attention on one detail, distracting and blinding them even to the most obvious and important clinical findings. This “inattentional blindness” is similar to the phenomenon demonstrated by Simons in the famous “invisible gorilla” psychological experiment. As much as practical, clinicians should attempt to assess referred patients independently before considering previous clinical information; including the question/s they were asked.

Exploring Undergraduates' Understanding of Photosynthesis Using Diagnostic Question Clusters

We present a diagnostic question cluster (DQC) that assesses undergraduates' thinking about photosynthesis. This assessment tool is not designed to identify individual misconceptions. Rather, it is focused on students' abilities to apply basic concepts about photosynthesis by reasoning with a coordinated set of practices based on a few scientific principles: conservation of matter, conservation of energy, and the hierarchical nature of biological systems. Data on students' responses to the cluster items and uses of some of the questions in multiple-choice, multiple-true/false, and essay formats are compared. A cross-over study indicates that the multiple-true/false format shows promise as a machine-gradable format that identifies students who have a mixture of accurate and inaccurate ideas. In addition, interviews with students about their choices on three multiple-choice questions reveal the fragility of students' understanding. Collectively, the data show that many undergraduates lack both a basic understanding of the role of photosynthesis in plant metabolism and the ability to reason with scientific principles when learning new content. Implications for instruction are discussed.

Using Targeted Active-Learning Exercises and Diagnostic Question Clusters to Improve Students' Understanding of Carbon Cycling in Ecosystems

In this study, we used targeted active-learning activities to help students improve their ways of reasoning about carbon flow in ecosystems. The results of a validated ecology conceptual inventory (diagnostic question clusters [DQCs]) provided us with information about students' understanding of and reasoning about transformation of inorganic and organic carbon-containing compounds in biological systems. These results helped us identify specific active-learning exercises that would be responsive to students' existing knowledge. The effects of the active-learning interventions were then examined through analysis of students' pre- and postinstruction responses on the DQCs. The biology and non–biology majors participating in this study attended a range of institutions and the instructors varied in their use of active learning; one lecture-only comparison class was included. Changes in pre- to postinstruction scores on the DQCs showed that an instructor's teaching method had a highly significant effect on student reasoning following course instruction, especially for questions pertaining to cellular-level, carbon-transforming processes. We conclude that using targeted in-class activities had a beneficial effect on student learning regardless of major or class size, and argue that using diagnostic questions to identify effective learning activities is a valuable strategy for promoting learning, as gains from lecture-only classes were minimal.

Percutaneous Minidose Metrizamide Endomyelographic Computed Tomography in Syringomyelia

Two patients presented with syringomyelia, each unusual. After neuroradiographic diagnosis with delayed metrizamide computed tomography (CT) or magnetic resonance imaging (MRI), an interesting diagnostic question arose. A percutaneous minidose metrizamide endomyelographic CT (PMDMECT) study clarified each situation and directly affected the neurosurgical approaches. The features of each case, the technique of PMDMECT, and postoperative follow-up data are reported.