bluuebunny/crossref_metadata_2025 huggingface dataset:
Effect of Caffeine on UVB‐induced Carcinogenesis, Apoptosis, and the Elimination of UVB‐induced Patches of p53 Mutant Epidermal Cells in SKH‐1 Mice†
Authors: Conney Allan H. , Kramata Pavel , Lou You‐Rong , Lu Yao‐Ping
Published: March 2008

Oral administration of green tea or caffeine to SKH‐1 mice during UVB irradiation for several months inhibited the formation of skin cancer. Similar effects were observed when green tea or caffeine was given to tumor‐free UVB‐initiated mice with a high risk of developing skin tumors in the absence of further UVB irradiation (high risk mice). Mechanistic studies indicated that topical application of caffeine stimulated UVB‐induced apoptosis as well as apoptosis in UVB‐induced focal hyperplasia and tumors in tumor‐bearing mice. Oral or topical administration of caffeine enhanced the removal of patches of epidermal cells with a mutant form of p53 protein that appeared early during the course of UVB‐induced carcinogenesis, and oral administration of caffeine altered the profile of p53 mutations in the patches. In additional studies, topical application of caffeine was shown to have a sunscreen effect, and topical application of caffeine sodium benzoate was more active than caffeine as a sunscreen and for stimulating UVB‐induced apoptosis. Caffeine sodium benzoate was also highly active in inhibiting carcinogenesis in UVB‐pretreated high risk mice. Our studies indicate that caffeine and caffeine sodium benzoate may be useful as novel inhibitors of sunlight‐induced skin cancer.
Green Tea Phenol Extracts Reduce UVB‐induced DNA Damage in Human Cells via Interleukin‐12†
Authors: Schwarz Agatha , Maeda Akira , Gan David , Mammone Tom , Matsui Mary S. , Schwarz Thomas
Published: March 2008

Green tea chemoprevention has been a focus of recent research, as a polyphenolic fraction from green tea (GTP) has been suggested to prevent UV radiation‐induced skin cancer. Recently, it was demonstrated that GTP reduced the risk for skin cancer in a murine photocarcinogenesis model. This was accompanied by a reduction in UV‐induced DNA damage. These effects appeared to be mediated via interleukin (IL)‐12, which was previously shown to induce DNA repair. Therefore, we studied whether GTP induction of IL‐12 and DNA repair could also be observed in human cells. KB cells and normal human keratinocytes were exposed to GTP 5 h before and after UVB. UVB‐induced apoptosis was reduced in UVB‐exposed cells treated with GTP. GTP induced the secretion of IL‐12 in keratinocytes. The reduction in UV‐induced cell death by GTP was almost completely reversed upon addition of an anti‐IL‐12‐antibody, indicating that the reduction of UV‐induced cell death by GTP is mediated via IL‐12. The ability of IL‐12 to reduce DNA damage and sunburn cells was confirmed in “human living skin equivalent” models. Hence the previously reported UV‐protective effects of GTP appear to be mediated in human cells via IL‐12, most likely through induction of DNA repair.
The Immunosuppressive Effects of Phthalocyanine Photodynamic Therapy in Mice Are Mediated by CD4+ and CD8+ T Cells and Can Be Adoptively Transferred to Naive Recipients†
Authors: Yusuf Nabiha , Katiyar Santosh K. , Elmets Craig A.
Published: March 2008

Photodynamic therapy (PDT) is a promising treatment modality for malignant tumors but it is also immunosuppressive which may reduce its therapeutic efficacy. The purpose of our study was to elucidate the role of CD4+ and CD8+ T cells in PDT immunosuppression. Using silicon phthalocyanine 4 (Pc4) as photosensitizer, nontumor‐bearing CD4 knockout (CD4−/−) mice and their wild type (WT) counterparts were subjected to Pc4‐PDT in a manner identical to that used for tumor regression (1 cm spot size, 0.5 mg kg−1 Pc4, 110 J cm−2 light) to assess the effect of Pc4‐PDT on cell‐mediated immunity. There was a decrease in immunosuppression in CD4−/− mice compared with WT mice. We next examined the role of CD8+ T cells in Pc4–PDT‐induced immunosuppression using CD8−/− mice following the same treatment regimen used for CD4−/− mice. Similar to CD4−/− mice, CD8−/− mice exhibited less immunosuppression than WT mice. Pc4–PDT‐induced immunosuppression could be adoptively transferred with spleen cells from Pc4–PDT treated donor mice to syngenic naive recipients (P < 0.05) and was mediated primarily by T cells, although macrophages were also found to play a role. Procedures that limit PDT‐induced immunosuppression but do not affect PDT‐induced regression of tumors may prove superior to PDT alone in promoting long‐term antitumor responses.
Early Events in UV Carcinogenesis—DNA Damage, Target Cells and Mutant p53 Foci†
Authors: De Gruijl Frank R. , Rebel Heggert
Published: March 2008

Skin carcinomas are the most common cancers in fair‐skinned populations of North West European descent. The risk is closely related to sun (UV) exposure and susceptibility to sunburn. Induction of squamous cell carcinomas (SCCs) in the skin of hairless mice by daily UVB exposure appears to emulate the genesis of these tumors in humans quite well. The carcinomas, and the UVB signature mutations that they carry in their p53 genes, can be linked most specifically to the induction of cyclobutane pyrimidine dimers (CPDs). The wavelength dependence of the induction of carcinomas parallels that of CPD induction over the UVB and UVA2 spectral regions. Microscopic clusters of cells overexpressing p53 with UVB signature mutations (“p53 patches”) can be detected in the interfollicular epidermis long before the skin tumors arise. DNA repair—more precisely nucleotide excision repair—is a crucial line of defense against UV‐induced p53 patches and skin carcinomas. Although chemoprevention of UV carcinogenesis, e.g. with difluoromethylornithine, may be successful by inhibiting the outgrowth of tumors, it may be better to counter the initial steps in tumor development. As the p53 patches appear to be potential precursors of SCCs, regression of p53 patches in unexposed skin should lower subsequent development of SCCs. However, “holoclonal” p53 patches might persist. Ablation of the interfollicular epidermis would be expected to abrogate development of SCC, and negation of this expectation [Faurschou A. et al., Exp. Dermatol. 2007;16:485–489] would indicate that SCCs stem from deep‐seated cells in the hair follicles. Careful examination of archival material showed that although most small p53 patches arise interfollicularly, some may actually arise high up in a follicle, in the infundibulum.
Cumulating Evidence about the Social Animal: Meta‐Analysis in Social‐Personality Psychology
Authors: Johnson Blair T. , Boynton Marcella H.
Published: March 2008

Like most scientific fields, social‐personality psychology has experienced an explosion of research related to such central topics as aggression, attraction, gender, group processes, motivation, personality, and persuasion, to name a few. The proliferation of research can be a monster unless it is tamed with the scientific review strategy of meta‐analysis, literally analyses of past analyses that produce a quantitative and empirical history of research on a particular phenomenon. The purpose of this article is to outline the basic process and statistics of meta‐analysis, as they pertain to social‐personality psychology. Meta‐analysis involves: (i) defining the problem under review; (ii) gathering qualified reports and putting their findings and methods into a database, (iii) analyzing that database, and (iv) interpreting the results and reporting them. Use of meta‐analytic strategies has paralleled the knowledge explosion in social‐personality psychology, but must be used and consumed with careful discernment if the cumulated evidence about the social animal, Homo sapiens, is to have maximal value.
Schism in Groups: A Social Psychological Account
Authors: Sani Fabio
Published: March 2008

Far from being monoliths, groups tend to be internally subdivided into competing factions that, in some cases, may leave the parent group thereby causing a schism. Although schisms are complex phenomena, research has revealed the existence of specific social psychological patterns that different schisms seem to have in common. A schism is normally triggered by the perception that a change (i.e., either the adoption of a new norm or the revision of an old norm) endorsed by the group majority denies the group identity and constitutes a rupture with its historically sedimented essence. Members of the faction opposing the change may or may not decide to leave the group, depending on their perceived ‘voice’ within the group. Feeling marginalised and discriminated against, rather than valued and respected within, the group will increase chances of joining a schism.
Modeling genetic connectivity in sticklebacks as a guideline for river restoration
Authors: Raeymaekers Joost A. M. , Maes Gregory E. , Geldof Sarah , Hontis Ingrid , Nackaerts Kris , Volckaert Filip A. M.
Published: March 2008

Estimating genetic connectivity in disturbed riverine landscapes is of key importance for river restoration. However, few species of the disturbed riverine fauna may provide a detailed and basin‐wide picture of the human impact on the population genetics of riverine organisms. Here we used the most abundant native fish, the three‐spined stickleback (Gasterosteus aculeatusL.), to detect the geographical determinants of genetic connectivity in the eastern part of the Scheldt basin in Belgium. Anthropogenic structures came out as the strongest determinant of population structure, when evaluated against a geographically well‐documented baseline model accounting for natural effects. These barriers not only affected genetic diversity, but they also controlled the balance between gene flow and genetic drift, and therefore may crucially disrupt the population structure of sticklebacks. Landscape models explained a high percentage of variation (allelic richness: adjustedR2 = 0.78; pairwiseFST: adjustedR2 = 0.60), and likely apply to other species as well. River restoration and conservation genetics may highly benefit from riverine landscape genetics, including model building, the detection of outlier populations, and a specific test for the geographical factors controlling the balance between gene flow and genetic drift.
Small‐scale biocomplexity in coastal Atlantic cod supporting a Darwinian perspective on fisheries management
Authors: Olsen Esben Moland , Knutsen Halvor , Gjøsæter Jakob , Jorde Per Erik , Knutsen Jan Atle , Stenseth Nils Chr.
Published: March 2008

Harvesting of marine resources raises concerns about how to identify and preserve biocomplexity, including the diversity of life histories found within and among wild populations of a species. In order to fully accomplish this, there is a need to elucidate the underlying causes of phenotypic variation, and how this variation responds to environmental changes. In general, both evolutionary (genetic) and nonevolutionary (plastic) responses may occur. Plastic responses to environmental change are expected to shift the phenotype along a reaction norm, while an evolutionary response is expected to shift the reaction norm itself. Here, we assess the maturation patterns of coastal Atlantic cod (Gadus morhua) in Skagerrak, where studies using neutral markers have revealed genetically differentiated populations of this harvested fish within tens of kilometres of coastline. Our results suggest that physiological state prior to the spawning season, as well as juvenile growth, both influence the probability of completing sexual maturation at a given age. Furthermore, our results point towards a spatial structuring of this plasticity (i.e. the maturation reaction norms) comparable with population connectivity inferred from neutral markers. We argue that such fine‐scale biocomplexity calls for a Darwinian approach to fisheries management.
Indian Traditional Medical Systems: An Overview on Ayurveda
Authors: Saxena Mohanji , Srivastava Vandita , Nayak Amiya
Published: March 2008

This article discuss about the role of herbs in Ayurveda and some recent Scientific findings on the benefits of Ayurvedic herbs.
Interview with Michelle Hinn
Authors: Hinn Michelle
Published: March 2008

Michelle Hinn
is an instructor in the Department of Library and Information Sciences at the University of Illinois where she teaches the game design course, and is the academic advisor for the Women in Math, Science, and Engineering Living/Learning Community. She was recently named one of Next Generation Magazine's 100 Most Influential Women in Gaming based on her work as chair of the IDGA Game Accessibility Special Interest Group. In the video interview, you will hear her answers the following questions:

1. You are writing a new book entitled "Accessibility and Usability in Game Design," can you tell us more about it?

2. You coauthored a book chapter "Literacy in the information age: inquiries into meaning-making with new technologies," what do you mean by "meaning-making" in that interesting title?

3. You are the chair of the Game Accessibility Special Interest Group of the International Game Developers Association, what are your goals and activities at IGDA?

4. How do you see the future of computer games?

5. Do you see a big difference between games designed for girls versus games designed for boys?
Interview with Joseph Olin
Authors: Olin Joseph
Published: March 2008

Joseph Olin
is the President of the Academy of Interactive Arts and Sciences (AIAS). He oversees the annual DICE Conference and Interactive Achievement Awards. Prior to AIAS, he spearheaded the introduction of gaming's most famous heroine, Lara Croft. He also launched Mattel's Generation Girl Teen Dolls product and the first Barbie brand advertising campaign. In the video interview, you will hear his answers to the following questions:

1. How do true game enthusiasts influence causal gamers?

2. Do you see a big difference between games designed for girls versus games designed for boys?

3. What is your view on games for the whole family?

4. You are the president of the Academy of Interactive Arts and Sciences, what are some of your goals and activities?
A new method for path prediction in network games
Authors: Li Shaolong , Chen Changja , Li Lei
Published: March 2008

In almost all multiplayer network games, dead-reckoning (DR) is used to predict the movements of game players, who can then predict the future movements of other players via the DR vectors they received. DR vectors, referred to as network packages, generally contain the position and velocity of game roles controlled by a sender at sending time. To achieve more accurate prediction, some games include the timestamp and acceleration of game roles in DR vectors. However, DR does not work well under bad network conditions. In our previous work [Li and Chen 2006] we proposed a solution called the interest scheme (IS), which proved to be efficient when network latency was unsteady and package loss frequent. Thus, in order to achieve much more accurate prediction, we proposed a hybrid solution. IS assumes that the path prediction for a given player is related to nearby objects or players. That is, that the players' surroundings can affect their movements, and different players may behave differently under the same conditions. In IS, a given player's surroundings are taken into account, and in order to achieve more accuracy, his habitual preferences are also taken into consideration. Experience with network games indicates that the same player will almost always behave in the same way under the same circumstances---for example, use the same fighting style. Moreover, we consider that different prediction methods should be used for different network latencies. So we introduce a hybrid method, which is a combination of IS, DR, and personal preferences. We use a 2D tank game to experiment, and compare the results of our solution with those of traditional methods. To obtain information on the players' habitual movements, we observed each participant for 30 minutes of play. Simulation shows that our method achieves significant improvements in path prediction.
Massively multiplayer online role-playing games
Authors: Achterbosch Leigh , Pierce Robyn , Simmons Gregory
Published: March 2008

Massively multiplayer online role-playing games (MMORPGs) are emerging in the computer game industry as a very popular genre. These games have existed since the late 1990s, but in the last few years the market has become increasingly strong. This relatively new genre is attracting a widespread audience, bringing together those who previously enjoyed both pen and paper and computer role-playing games, as well as those who enjoy socializing with other players in a virtual environment. Game developers see MMORPGs as a potentially profitable business due to its widespread appeal, but the reality is that only a small percentage of MMORPGs that are released become a success [Kosak 2006].

This article attempts to determine the many aspects that make a successful MMORPG; it also attempts to ascertain what new and innovative features are expected by the users from the next generation of MMORPGs. This is achieved by looking at and discussing past literature and surveying the MMORPG community's perception of previous and current MMORPGs, as well as their expectations of the next generation.

An online survey attracted 122 participants to provide their perceptions of current and past MMORPGs. This article determines and outlines the respondents' preferences in the MMORPG genre, discussing what implications these could have on its future. The survey also gave insight into the respondents' expectations of the future of MMORPGs. We conclude this article with a discussion of aspects of current MMORPGs that the participants would like improved, as well as new features they would like incorporated into the next generation of games.
Game on
Authors: Davison Chris
Published: March 2008

Seamus Blackley is head of the Games Department at Creative Artists Agency (CAA), where his role is to define and execute CAA's global strategy for representing many of the world's most respected and successful game creators. Under Blackley's leadership, the Games Department specializes in securing and negotiating game production deals with publishers, financiers, film and television studios, and networks, as well as building and advising development companies to give game designers greater creative and financial control. I interviewed Seamus in December 2007 to discuss physics, social networking, in-game advertising and convergence.
Parallel unsymmetric-pattern multifrontal sparse LU with column preordering
Authors: Avron Haim , Shklarski Gil , Toledo Sivan
Published: March 2008

We present a new parallel sparse LU factorization algorithm and code. The algorithm uses a column-preordering partial-pivoting unsymmetric-pattern multifrontal approach. Our baseline sequential algorithm is based on UMFPACK 4, but is somewhat simpler and is often somewhat faster than UMFPACK version 4.0. Our parallel algorithm is designed for shared-memory machines with a small or moderate number of processors (we tested it on up to 32 processors). We experimentally compare our algorithm with SuperLU_MT, an existing shared-memory sparse LU factorization with partial pivoting. SuperLU_MT scales better than our new algorithm, but our algorithm is more reliable and is usually faster. More specifically, on matrices that are costly to factor, our algorithm is usually faster on up to 4 processors, and is usually faster on 8 and 16. We were not able to run SuperLU_MT on 32. The main contribution of this article is showing that the column-preordering partial-pivoting unsymmetric-pattern multifrontal approach, developed as a sequential algorithm by Davis in several recent versions of UMFPACK, can be effectively parallelized.
On the design of interfaces to sparse direct solvers
Authors: Sala Marzio , Stanley Kendall S. , Heroux Michael A.
Published: March 2008

We discuss the design of general, flexible, consistent, reusable, and efficient interfaces to software libraries for the direct solution of systems of linear equations on both serial and distributed memory architectures. We introduce a set of abstract classes to access the linear system matrix elements and their distribution, access vector elements, and control the solution of the linear system.

We describe a concrete implementation of the proposed interfaces, and report examples of applications and numerical results showing that the overhead induced by the object-oriented design is negligible under typical conditions of usage. We include examples of applications, and we comment on the advantages and limitations of the design.
Scalable parallelization of FLAME code via the workqueuing model
Authors: Zee Field G. Van , Bientinesi Paolo , Low Tze Meng , Geijn Robert A. van de
Published: March 2008

We discuss the OpenMP parallelization of linear algebra algorithms that are coded using the Formal Linear Algebra Methods Environment (FLAME) API. This API expresses algorithms at a higher level of abstraction, avoids the use loop and array indices, and represents these algorithms as they are formally derived and presented. We report on two implementations of the workqueuing model, neither of which requires the use of explicit indices to specify parallelism. The first implementation uses the experimental taskq pragma, which may influence the adoption of a similar construct into OpenMP 3.0. The second workqueuing implementation is domain-specific to FLAME but allows us to illustrate the benefits of sorting tasks according to their computational cost prior to parallel execution. In addition, we discuss how scalable parallelization of dense linear algebra algorithms via OpenMP will require a two-dimensional partitioning of operands much like a 2D data distribution is needed on distributed memory architectures. We illustrate the issues and solutions by discussing the parallelization of the symmetric rank-k update and report impressive performance on an SGI system with 14 Itanium2 processors.
The mystery of "b := (b = false)"
Authors: Reges Stuart
Published: March 2008

This paper describes some unusual patterns that emerged from a statistical analysis of the 1988 Advanced Placement Exam in Computer Science. Most multiple-choice questions on the exam had few significant correlations with other parts of the exam. But a small set of five questions had a nontrivial correlation with many parts of the test. One question in particular demonstrated such correlations. It asked about the effect of the assignment statement "b := (b = false)" for a boolean variable b. One interpretation of this data is that these questions are testing general programming aptitude. The paper presents the analysis along with a discussion of the possible implications.
A principled approach to teaching OO first
Authors: Gries David
Published: March 2008

There has been debate about whether OO should, or even can, be taught first in CS1 (using Java). We claim that OO can be taught successfully, provided certain principles are followed. These principles lead to the requirement of an appropriate model for classes and objects, which we provide.
Bantam
Authors: Corliss Marc L. , Lewis E. Christopher
Published: March 2008

This paper introduces the Bantam Java compiler project, a new language and compiler designed specifically for the classroom Bantam Java, the source programming language, is a small subset of the Java language, which is a commonly-used language in introductory programming courses. Because Bantam Java is similar to Java, it leverages the student's existing intuition and the student can automatically apply what they learn in the course directly to Java. The Bantam Java project is also customizable (it supports several tools and targets), which gives instructors flexibility in designing course assignments. Finally, the Bantam Java compiler project includes a free, comprehensive, student manual which can be used in conjunction with any compiler textbook.
Engaging constructions
Authors: Doyle Maureen , Kirby Kevin G. , Newell Gary
Published: March 2008

In this paper, we describe projects that engage Hispanic middle-school age students with computing, and cast these projects within the ECC ("Engagement, Capacity, Continuity") framework. Our projects were undertaken in the Midwestern United States, where recent heavy immigration from Latin America has caused rapid demographic shifts. We have conducted computing workshops that are cognizant of the cultural milieu of recent immigrants, in that they are family-based, are offered at familiar sites in the community, and give participants a chance to be constructors of technology rather than mere "end-users." We present these efforts as forces that generate a flow that carries immigrant youths up to the point of beginning an undergraduate major in computing.
A course in collaborative computing
Authors: Clear Tony , Kassabova Diana
Published: March 2008

Recent calls for a new discipline of 'web science' have proposed extending computer science to incorporate the social dimensions of computing. In this paper we outline a Masters course in Collaborative Computing, which employs a combination of collaborative pedagogy, collaborative technologies, and a corpus of research data from Global Virtual Teams to blend the technology and the social dimensions within a research linked course context. We review the effectiveness of this model of learning and the conduct of the course over the five years since its inception.
Improving pedagogical feedback and objective grading
Authors: Ahoniemi Tuukka , Lahtinen Essi , Reinikainen Tommi
Published: March 2008

It is important for learning that students receive enough of educational feedback of their work. To get the students to be seriously disposed to the feedback it has to be personal, objective and consistent. In large classes ensuring such feedback can be difficult. Grading rubrics are a solution to the objectivity and consistency.

ALOHA is an online grading tool based on rubrics which all the graders have to use. Particularly, ALOHA provides features that make the grading process more convenient for the graders and the teacher. By facilitating the graders work ALOHA allows them to focus more on feedback writing.

To test the effectiveness of ALOHA in objectivity and consistency we did a comparative statistical analysis on the distribution of grades. The results supported the assumptions showing improvement resulting in similar distribution of grades amongst different graders who used the tool.
APOGEE
Authors: Fu Xiang , Peltsverger Boris , Qian Kai , Tao Lixin , Liu Jigang
Published: March 2008

Providing consistent, instant, and detailed feedback to students has been a great challenge in teaching Web based computing. We present the prototype of an automated grading system called ProtoAPOGEE for enriching students' learning experience and elevating faculty productivity. Unlike other automated graders used in introductory programming classes, ProtoAPOGEE emphasizes the examination of quality attributes of student project submissions, in addition to the basic functionality requirements. The tool is able to generate step by step play-back guidance for failed test cases, hence providing informative feedback to help students make reflective and iterative improvements in learning.
Misunderstandings about object-oriented design
Authors: Turner Scott A. , Quintana-Castillo Ricardo , Pérez-Quiñones Manuel A. , Edwards Stephen H.
Published: March 2008

In this paper we present our experience using code reviews in a CS2 course. In particular, we highlight a series of misunderstandings of object-oriented (OO) concepts we observed as a by-product of the code review exercise. In our activity, we asked students to review code, rate it using a rubric, and to justify their explanation. The students were asked to review two solutions to a project from a previous year. Through examples of their explanations, we found that students had a number of basic misunderstandings of object-oriented principles. In this paper, we present our observations of the misunderstandings, and present some general observations of how code reviews can be used as an assessment tool in CS2.
Can students reengineer?
Authors: Leach Ronald J. , Burge Legand L. , Keeling Harry N.
Published: March 2008

A recent paper by David Lechner stated that for many long-lived systems, it is more efficient to reengineer portions of systems than to continually repair them. That paper made an implicit assumption about the ability of software engineers to determine precisely which software should be reengineered. We report the results of a study that addresses the readiness of graduates, who will soon be beginning software engineers, to make such an assessment, based on comprehension of reusable vs. reengineered software. We address this comprehension in the context of software engineering education.
Towards a top-down approach to teaching an undergraduate grid computing course
Authors: Wilkinson Barry , Ferner Clayton
Published: March 2008

Early undergraduate Grid computing courses generally took a bottom-up approach to Grid computing education starting with network protocols, client-server concepts, creating Web and Grid services, and then progressing through the underlying Grid computing middleware, security mechanisms and job submission all using a Linux command-line interface. We describe a new approach to teaching Grid computing beginning with a production-style Grid portal, registration process, and job submission, and then leading into infrastructure details. We incorporate seven assignments, several of which require students to install Grid computing software on their own computer or lab computers rather than using centralized servers. Students complete a "capstone" mini-project. Typical projects included creating a JSR 168 portlet user interface for an application. We describe our experiences using this new course structure.
Games, stories, or something more traditional
Authors: Cliburn Daniel C. , Miller Susan
Published: March 2008

In this paper, we describe a study designed to examine the types of projects college students prefer in an introductory programming course. For three assignments in a course, students were given a choice among three project types: a game, a "choose your own adventure" story, and a more traditional project (such as a problem from the text book). During the semester, 35 of 49 projects submitted by students were the game option (71.4%), with only two projects submitted that were stories. A statistical analysis revealed that student choices on assignments did not appear to be related to their overall performance in the course. On an end of term survey, students commented that they often chose projects that had all requirements clearly explained, and avoided assignments that were open-ended in nature.
Experience offering a course centered on cyberporn
Authors: Oldham Joseph D.
Published: March 2008

In Spring Semester 2007 our small liberal arts college offered a new course, Computer Science 150, Cyberporn: A Seminar in Computing and Society. I proposed and taught the course as a one-hour seminar style course with no prerequisite. This paper describes the course, including motivation and student response.
Debugging
Authors: Murphy Laurie , Lewandowski Gary , McCauley Renée , Simon Beth , Thomas Lynda , Zander Carol
Published: March 2008

A qualitative analysis of debugging strategies of novice Java programmers is presented. The study involved 21 CS2 students from seven universities in the U.S. and U.K. Subjects "warmed up" by coding a solution to a typical introductory problem. This was followed by an exercise debugging a syntactically correct version with logic errors. Many novices found and fixed bugs using strategies such as tracing, commenting out code, diagnostic print statements and methodical testing. Some competently used online resources and debuggers. Students also used pattern matching to detect errors in code that "just didn't look right". However, some used few strategies, applied them ineffectively, or engaged in other unproductive behaviors. This led to poor performance, frustration for some, and occasionally the introduction of new bugs. Pedagogical implications and suggestions for future research are discussed.
Compiler error messages
Authors: Nienaltowski Marie-Hélène , Pedroni Michela , Meyer Bertrand
Published: March 2008

Novices find it difficult to understand and use compiler error messages. It is useful to refine this observation and study the effect of different message styles on how well and quickly students identify errors in programs. For example, does an increased level of detail simplify the understanding of errors and their correction? We analyzed messages produced by a number of compilers for five programming languages, and grouped them into three style categories from their level of detail and presentation format, and correlated the level of experience and error type with performance and speed of response. The study involved two groups of students taking an introductory programming course at two different institutions; they used messages in these three styles to debug erroneous code. The results indicate that more detailed messages do not necessarily simplify the understanding of errors but that it matters more where information is placed and how it is structured.
Improving computer science diversity through summer camps
Authors: Groth Dennis P. , Hu Helen H. , Lauer Betty , Lee Hwajung
Published: March 2008

Summer camps offer a ripe opportunity for increasing computer science diversity. This panel provides several examples of summer camps that specifically recruit from traditionally underrepresented demographics. The panelists run camps at a community college, a private liberal-arts college, and public universities. The camps are residential and day camps, coed and all-female camps, ranging from three-days to two-weeks long, with campers from 10-years-olds to high school seniors. In addition to describing their camps, the panelists will provide information on securing funding, recruiting campers from underrepresented populations, measuring impact, and lessons learned along the way. Demonstrations of what campers accomplished will also be shown.
Implementation of threads as an operating systems project
Authors: Donaldson John L.
Published: March 2008

In this paper the author describes a two-part programming assignment that has been used in an undergraduate operating systems course. The assignment is to write a user-level thread library, similar to the POSIX pthreads library, for a Unix or linux system.
Innovation, design, and simplicity at google
Authors: Mayer Marissa
Published: March 2008

This talk will cover the philosophies of innovation and design at Google, complete with examples of how these philosophies have affected and produced various Google services. Other topics to be covered include: how Google approaches building products with simplicity, its pragmatic and experimental approach to launching products, and a discussion of the academic computer science skills that large, distributed, web-based systems like Google require.
Publishing in computing education
Authors: Tenenberg Josh , Fincher Sally , Impagliazzo John , Joyce Daniel
Published: March 2008

This panel is directed to members of the SIGCSE community who would like to learn more about the places to publish in computing education and how to get published there. This panel brings together conference, journal, and book-series editors to share their insights as "gatekeepers" of their respective publication venues.
Struggles of new college graduates in their first software development job
Authors: Begel Andrew , Simon Beth
Published: March 2008

How do new college graduates experience their first software development jobs? In what ways are they prepared by their educational experiences, and in what ways do they struggle to be productive in their new positions? We report on a "fly-on-the-wall" observational study of eight recent college graduates in their first six months of a software development position at Microsoft Corporation. After a total of 85 hours of on-the-job observation, we report on the common abilities evidenced by new software developers including how to program, how to write design specifications, and evidence of persistence strategies for problem-solving. We also classify some of the common ways new software developers were observed getting stuck: communication, collaboration, technical, cognition, and orientation. We report on some common misconceptions of new developers which often frustrate them and hinder them in their jobs, and conclude with recommendations to align Computer Science curricula with the observed needs of new professional developers.
Isn't it time you had an emulab?
Authors: Laverell W. David , Fei Zongming , Griffioen James N.
Published: March 2008

Emulabs, network testbeds on which experiments can be carried out through a web interface, are widely recognized as useful
research
environments. We believe that Emulabs are also excellent platforms for
teaching
courses in operating systems and networking. Moreover, equipment costs have fallen, and Emulab software has evolved, to the point where any school could conceivably afford their own. This raises the obvious question: "Should institutions build and operate their own Emulab?". To get a handle on this question, we describe our experiences building and operating
Edulabs
--Emulabs specifically designed for education--at Calvin College and the University of Kentucky. We argue that with the right technical support, owning and operating one's own Emulab is a worthwhile endeavor that has many benefits. We acknowledge, however, that in the absence of good technical support, deploying one's own Emulab can be a difficult enterprise. We also describe how we enhanced Emulab to improve its utility in an educational setting.
CS 0.5
Authors: Sloan Robert H. , Troy Patrick
Published: March 2008

There are often problems when students enter a course with widely different experience levels with key course topics. If the material is covered too slowly, those with greater experience get bored and lose interest. If the material is covered too quickly, those with less experience get lost and feel incompetent. This problem with incoming students of our Computer Science Major led us to create CS 0.5: an introductory Computer Science course to target those CS majors who have little or no background with programming. Our goal is to provide these students with an engaging curriculum and prepare them to keep pace in future courses with those students who enter with a stronger background.

Following the lead of Mark Guzdial's work on using media computation for non-majors at Georgia Tech, we use media computation as the tool to provide this engaging curriculum. We report here on our experience to date using the CS 0.5 approach with a media computation course.
Pre-programming analysis tutors help students learn basic programming concepts
Authors: Jin Wei
Published: March 2008

In this paper, we describe a scaffolding technique - pre-programming-analysis guided programming (PAGP) - developed to help students grasp basic programming concepts. Two different ways to implement the PAGP process in a classroom were developed and then compared: one for students to fill out an analysis form, and the other for students to interact with online cognitive tutors. Our results show that the PAGP process helps students learn better and faster, especially with the assistance of the online tutors.
A novel approach to K-12 CS education
Authors: Hart Mindy , Early James P. , Brylow Dennis
Published: March 2008

This paper describes a continuing series of summer workshops hosted by Purdue University entitled "Linking Mathematics and Computer Science." Each is designed to inform and inspire high school teachers of mathematics with an interest in computer science. Originally conceived as an extension of our existing K-12 outreach, our workshop aims to provide teachers with innovative activities and ideas that link their secondary school mathematics curriculum with computer science. By reaching out to high school math teachers, we hope to in turn reach a broader base of students outside of computer science classes. By fostering interest in this broader audience, we can increase the number of students entering undergraduate computer science programs, and reach a larger segment of underrepresented populations.
The game of life
Authors: Ladner Richard E. , VanDeGrift Tammy
Published: March 2008

In this hands-on special session, attendees will learn about and use a Game of Life cellular automata framework (Java) to assist with outreach activities. Using the framework, students with no prior programming experience can create interesting behaviors within thirty minutes. The special session leaders have successfully used this approach for thirteen years in a one-week summer workshop for disabled high school students. The SIGCSE special session will include an introduction to the framework and keys to its success as an outreach activity, followed by participants solving, programming, and proposing specific problems. Attendees will be equipped to guide Game of Life outreach activities at their own outreach events.
Defense against the dark arts
Authors: Bailey Mark W. , Coleman Clark L. , Davidson Jack W.
Published: March 2008

Computer science faculty must attract and retain students by offering innovative courses that spark student interest, yet still teach core, computer science concepts. These efforts have become particularly important as computer science enrollments have declined, thus increasing concerns for attracting and retaining students. We describe an innovative course that leverages students' interest in computer security issues to attract and retain technically-oriented students. Our initial vision was to offer a course covering computer viruses - a subject that even a novice computer user has some familiarity. To avoid the controversy associated with teaching students how to write malicious software, we focused the course on techniques for defending against viruses, so we named the course Defense Against the Dark Arts. In teaching the course, we have found the subject matter provides an engaging way to introduce and reinforce many important computer science concepts that other courses often cover, most particularly, the traditional compiler course. We have taught the course three times at two separate institutions, with a third school soon to follow. The course has been well received by students - completely filling each semester with enrollments that are four to five times greater than the compiler course. Furthermore, student surveys indicate that the course raises students' awareness of computer security while introducing students to important program translation and analysis concepts.
Moving beyond security tracks
Authors: Taylor Blair , Azadegan Shiva
Published: March 2008

In response to the national computer security crisis, colleges and universities have developed security tracks and specialized security courses. While security tracks are effective at producing security experts, they only reach a small subset of students and occur after students have established a foundation of coding techniques. Most undergraduate computing students learn programming and design with little regard to security issues.

To complement our security track and reach all computing students at the beginning of their studies, we piloted security integration across sections of CS0 and CS1, using a series of security laboratory modules. Preliminary results show increased security knowledge in the security-targeted sections. This paper describes the details and results of this pilot, which serves as a model for further integration throughout the CS curriculum.
Serious fun
Authors: Huss-Lederman Steven , Chinn Donald , Skrentny James
Published: March 2008

In this special session, participants will learn how to use Peer-Led Team Learning (PLTL) effectively in computer science courses. This technique has been successful in reducing drop rates and increasing satisfaction among students. Therefore, it holds promise as a way to boost sagging computer science enrollments in general, and to increase participation of under-represented groups in particular. The goal of the session is to give participants practical information and hands-on experience.
Evolving an integrated curriculum for object-oriented analysis and design
Authors: Ramnath Sarnath , Dathan Brahma
Published: March 2008

Object-Oriented Analysis and Design has established itself as an integral and critically vital part of the software development process. In this paper, we describe an integrated approach to teaching this subject so that it covers vital components of this vast field: analysis, object-oriented design principles such as the Liskov Substitution Principle, the design process, which shows how and where the rules are applied, modeling, design and architectural patterns, language features, and refactoring. The course has evolved over the past 10 years to one that revolves around three major case studies. This evolution has resulted in a course that covers all important aspects of OOAD in a manner that emphasizes their inter-relatedness and hence their relevance to overall design process. Feedback suggests that this approach has improved students' understanding of the OOAD concepts.
Socially relevant computing
Authors: Buckley Michael , Nordlinger John , Subramanian Devika
Published: March 2008

In this paper, we introduce socially relevant computing as a new way to reinvigorate interest in computer science. Socially relevant computing centers on the use of computation to solve problems that students are most passionate about. It draws on both the solipsistic and altruistic side of the current generation of students. It presents computer science as a cutting-edge technological discipline that empowers them to solve problems of personal interest (socially relevant with a little s), as well as problems that are important to society at large (socially relevant with a capital s). We believe that socially relevant computing offers a vision of computer science that has the potential to improve the quantity, quality and diversity of students in our discipline. We describe preliminary results from two on-going curricular experiments at SUNY Buffalo and at Rice University that implement our vision of socially relevant computing.
Forging connections between life and class using reading assignments
Authors: Sudol Leigh Ann
Published: March 2008

This paper describes an experiment involving incorporating reading assignments into an introductory programming class at the university level. Results indicate that assignments of this type help students make connections between the concepts they are studying, and computer science in general, with their everyday lives.
Programming by choice
Authors: Maloney John H. , Peppler Kylie , Kafai Yasmin , Resnick Mitchel , Rusk Natalie
Published: March 2008

This paper describes Scratch, a visual, block-based programming language designed to facilitate media manipulation for novice programmers. We report on the Scratch programming experiences of urban youth ages 8-18 at a Computer Clubhouse 'an after school center' over an 18-month period. Our analyses of 536 Scratch projects collected during this time documents the learning of key programming concepts even in the absence of instructional interventions or experienced mentors. We discuss the motivations of urban youth who choose to program in Scratch rather than using one of the many other software packages available to them and the implications for introducing programming at after school settings in underserved communities.
Cybercivics
Authors: Owens Jim , Matthews Jeanna
Published: March 2008

This paper describes CyberCivics, a novel approach to computer science outreach that integrates hands-on computing experiences with the study of contemporary social and political issues. We provide details of one such curriculum, focused on electronic voting, that we used with a high school AP Government course in Spring 2007. We describe our experience with this curriculum and how it enabled us to reach a larger, more diverse and more academically prepared group of students than prior outreach efforts targeted directly at computing courses. We also suggest a number of alternative approaches to outreach based on the CyberCivics idea.