bluuebunny/crossref_metadata_2025 huggingface dataset:
A model‐based scatter artifacts correction for cone beam CT
Authors: Zhao Wei , Vernekohl Don , Zhu Jun , Wang Luyao , Xing Lei
Published: March 2016

Purpose:

Due to the increased axial coverage of multislice computed tomography (CT) and the introduction of flat detectors, the size of x‐ray illumination fields has grown dramatically, causing an increase in scatter radiation. For CT imaging, scatter is a significant issue that introduces shading artifact, streaks, as well as reduced contrast and Hounsfield Units (HU) accuracy. The purpose of this work is to provide a fast and accurate scatter artifacts correction algorithm for cone beam CT (CBCT) imaging.

Methods:

The method starts with an estimation of coarse scatter profiles for a set of CBCT data in either image domain or projection domain. A denoising algorithm designed specifically for Poisson signals is then applied to derive the final scatter distribution. Qualitative and quantitative evaluations using thorax and abdomen phantoms with Monte Carlo (MC) simulations, experimental Catphan phantom data, and in vivo human data acquired for a clinical image guided radiation therapy were performed. Scatter correction in both projection domain and image domain was conducted and the influences of segmentation method, mismatched attenuation coefficients, and spectrum model as well as parameter selection were also investigated.

Results:

Results show that the proposed algorithm can significantly reduce scatter artifacts and recover the correct HU in either projection domain or image domain. For the MC thorax phantom study, four‐components segmentation yields the best results, while the results of three‐components segmentation are still acceptable. The parameters (iteration number K and weight β) affect the accuracy of the scatter correction and the results get improved as K and β increase. It was found that variations in attenuation coefficient accuracies only slightly impact the performance of the proposed processing. For the Catphan phantom data, the mean value over all pixels in the residual image is reduced from −21.8 to −0.2 HU and 0.7 HU for projection domain and image domain, respectively. The contrast of the in vivo human images is greatly improved after correction.

Conclusions:

The software‐based technique has a number of advantages, such as high computational efficiency and accuracy, and the capability of performing scatter correction without modifying the clinical workflow (i.e., no extra scan/measurement data are needed) or modifying the imaging hardware. When implemented practically, this should improve the accuracy of CBCT image quantitation and significantly impact CBCT‐based interventional procedures and adaptive radiation therapy.
The nutrient sensor OGT in PVN neurons regulates feeding
Authors: Lagerlöf Olof , Slocomb Julia E. , Hong Ingie , Aponte Yeka , Blackshaw Seth , Hart Gerald W. , Huganir Richard L.
Published: March 2016

When enough isn't enough

Overeating and obesity are rapidly becoming worldwide problems. Normally, mice do not overeat—they balance their caloric intake with their caloric needs. Lagerlöf
et al.
deleted an enzyme called O-GlcNAc transferase (OGT) from a subset of neurons in the mouse hypothalamus (see the Perspective by Schwartz). After the loss of OGT, the animals began to overeat and rapidly gained weight. The animals ate more at meal times, rather than eating more often. Thus, OGT seems to regulate satiety and helps to couple caloric intake to caloric need.

Science
, this issue p.
1293
; see also p.
1268
Surface compositions across Pluto and Charon
Authors: Grundy W. M. , Binzel R. P. , Buratti B. J. , Cook J. C. , Cruikshank D. P. , Dalle Ore C. M. , Earle A. M. , Ennico K. , Howett C. J. A. , Lunsford A. W. , Olkin C. B. , Parker A. H. , Philippe S. , Protopapa S. , Quirico E. , Reuter D. C. , Schmitt B. , Singer K. N. , Verbiscer A. J. , Beyer R. A. , Buie M. W. , Cheng A. F. , Jennings D. E. , Linscott I. R. , Parker J. Wm. , Schenk P. M. , Spencer J. R. , Stansberry J. A. , Stern S. A. , Throop H. B. , Tsang C. C. C. , Weaver H. A. , Weigle G. E. , Young L. A. ,   and the New Horizons Science Team
Published: March 2016

New Horizons unveils the Pluto system

In July 2015, the New Horizons spacecraft flew through the Pluto system at high speed, humanity's first close look at this enigmatic system on the outskirts of our solar system. In a series of papers, the New Horizons team present their analysis of the encounter data downloaded so far: Moore
et al.
present the complex surface features and geology of Pluto and its large moon Charon, including evidence of tectonics, glacial flow, and possible cryovolcanoes. Grundy
et al.
analyzed the colors and chemical compositions of their surfaces, with ices of H
2
O, CH
4
, CO, N
2
, and NH
3
and a reddish material which may be tholins. Gladstone
et al.
investigated the atmosphere of Pluto, which is colder and more compact than expected and hosts numerous extensive layers of haze. Weaver
et al.
examined the small moons Styx, Nix, Kerberos, and Hydra, which are irregularly shaped, fast-rotating, and have bright surfaces. Bagenal
et al.
report how Pluto modifies its space environment, including interactions with the solar wind and a lack of dust in the system. Together, these findings massively increase our understanding of the bodies in the outer solar system. They will underpin the analysis of New Horizons data, which will continue for years to come.

Science
, this issue pp.
1284
,
10.1126/science.aad9189
,
10.1126/science.aad8866
,
10.1126/science.aae0030
, &
10.1126/science.aad9045
Comment on “Unique in the shopping mall: On the reidentifiability of credit card metadata”
Authors: Sánchez David , Martínez Sergio , Domingo-Ferrer Josep
Published: March 2016

De Montjoyeet al. (Reports, 30 January 2015, p. 536) claimed that most individuals can be reidentified from a deidentified transaction database and that anonymization mechanisms are not effective against reidentification. We demonstrate that anonymization can be performed by techniques well established in the literature.
New mechanisms, new worries
Authors: Sprenger Marc , Fukuda Keiji
Published: March 2016

The increasing spread of colistin resistance is resulting in untreatable infections
SCS macrophages suppress melanoma by restricting tumor-derived vesicle–B cell interactions
Authors: Pucci Ferdinando , Garris Christopher , Lai Charles P. , Newton Andita , Pfirschke Christina , Engblom Camilla , Alvarez David , Sprachman Melissa , Evavold Charles , Magnuson Angela , von Andrian Ulrich H. , Glatz Katharina , Breakefield Xandra O. , Mempel Thorsten R. , Weissleder Ralph , Pittet Mikael J.
Published: March 2016

Macrophages block tumors' spread

Tumors constantly communicate with their surrounding tissue and the immune system. One way tumors likely do this is by secreting extracellular vesicles (tEVs), which can carry bits of the tumor to distant sites in the body. Pucci
et al.
tracked tEVs in tumor-bearing mice and people and studied how they affect cancer progression. They found that tEVs disseminate through lymph to nearby lymph nodes, where a specialized population of macrophages largely block any further travel. This barrier breaks down, however, as cancer progresses and also in the face of certain therapies. The tEVs can then penetrate lymph nodes, where they interact with B cells that promote further tumor growth.

Science
, this issue p.
242
Draft Genome Sequences of 10
Bacillus subtilis
Strains That Form Spores with High or Low Heat Resistance
Authors: Berendsen Erwin M. , Wells-Bennik Marjon H. J. , Krawczyk Antonina O. , de Jong Anne , van Heel Auke , Eijlander Robyn T. , Kuipers Oscar P.
Published: March 2016

Here, we report the draft genome sequences of 10 isolates of
Bacillus subtilis
, a spore forming Gram-positive bacterium. The strains were selected from food products and produced spores with either high or low heat resistance.
Epidemic potential ofEscherichia coliST131 andKlebsiella pneumoniaeST258: a systematic review and meta-analysis
Authors: Dautzenberg M J D , Haverkate M R , Bonten M J M , Bootsma M C J
Published: March 2016

Objectives

Observational studies have suggested thatEscherichia colisequence type (ST) 131 andKlebsiella pneumoniaeST258 have hyperendemic properties. This would be obvious from continuously high incidence and/or prevalence of carriage or infection with these bacteria in specific patient populations. Hyperendemicity could result from increased transmissibility, longer duration of infectiousness, and/or higher pathogenic potential as compared with other lineages of the same species. The aim of our research is to quantitatively estimate these critical parameters forE. coliST131 andK. pneumoniaeST258, in order to investigate whetherE. coliST131 andK. pneumoniaeST258 are truly hyperendemic clones.

Primary outcome measures

A systematic literature search was performed to assess the evidence of transmissibility, duration of infectiousness, and pathogenicity forE. coliST131 andK. pneumoniaeST258. Meta-regression was performed to quantify these characteristics.

Results

The systematic literature search yielded 639 articles, of which 19 data sources provided information on transmissibility (E. coliST131 n=9;K. pneumoniaeST258 n=10)), 2 on duration of infectiousness (E. coliST131 n=2), and 324 on pathogenicity (E. coliST131 n=285;K. pneumoniaeST258 n=39). Available data on duration of carriage and on transmissibility were insufficient for quantitative assessment. In multivariable meta-regressionE. coliisolates causing infection were associated with ST131, compared to isolates only causing colonisation, suggesting thatE. coliST131 can be considered more pathogenic than non-ST131 isolates. Date of isolation, location and resistance mechanism also influenced the prevalence of ST131.E. coliST131 was 3.2 (95% CI 2.0 to 5.0) times more pathogenic than non-ST131. ForK. pneumoniaeST258 there were not enough data for meta-regression assessing the influence of colonisation versus infection on ST258 prevalence.

Conclusions

With the currently available data, it cannot be confirmed nor rejected, thatE. coliST131 orK. pneumoniaeST258 are hyperendemic clones.
Smoke-free homes: what are the barriers, motivators and enablers? A qualitative systematic review and thematic synthesis
Authors: Passey Megan E , Longman Jo M , Robinson Jude , Wiggers John , Jones Laura L
Published: March 2016

Objective

To thematically synthesise primary qualitative studies of the barriers, motivators and enablers of smoke-free homes (SFHs).

Design

Systematic review and thematic synthesis.

Data sources

Searches of MEDLINE, EBM Reviews (Cochrane Database of Systematic Reviews), PsycINFO, Global Health, CINAHL, Web of Science, Informit and EMBASE, combining terms for families, households and vulnerable populations; SFH and secondhand smoke; and qualitative research, were supplemented by searches of PhD theses, key authors, specialist journals and reference lists.

Study selection

We included 22 articles, reporting on 18 studies, involving 646 participants. Inclusion criteria: peer-reviewed; English language; published from 1990 onwards (to week 3 of April 2014); used qualitative data collection methods; explored participants’ perspectives of home smoking behaviours; and the barriers, motivators and enablers to initiating and/or maintaining a SFH.

Data extraction

1 of 3 authors extracted data with checking by a second.

Data synthesis

A thematic synthesis was performed to develop 7 core analytic themes: (1) knowledge, awareness and risk perception; (2) agency and personal skills/attributes; (3) wider community norms and personal moral responsibilities; (4) social relationships and influence of others; (5) perceived benefits, preferences and priorities; (6) addiction and habit; (7) practicalities.

Conclusions

This synthesis highlights the complexity faced by many households in having a SFH, the practical, social, cultural and personal issues that need to be addressed and balanced by households, and that while some of these are common across study settings, specific social and cultural factors play a critical role in shaping household smoking behaviours. The findings can inform policy and practice and the development of interventions aimed at increasing SFHs.

Trial registration number

CRD42014014115.
Do patients hospitalised in high-minority hospitals experience more diversion and poorer outcomes? A retrospective multivariate analysis of Medicare patients in California
Authors: Shen Yu-Chu , Hsia Renee Y
Published: March 2016

Objective

We investigated the association between crowding as measured by ambulance diversion and differences in access, treatment and outcomes between black and white patients.

Design

Retrospective analysis.

Setting

We linked daily ambulance diversion logs from 26 California counties between 2001 and 2011 to Medicare patient records with acute myocardial infarction and categorised patients according to hours in diversion status for their nearest emergency departments on their day of admission: 0, <6, 6 to <12 and ≥12 h. We compared the amount of diversion time between hospitals serving high volume of black patients and other hospitals. We then use multivariate models to analyse changes in outcomes when patients faced different levels of diversion, and compared that change between black and white patients.

Participants

29 939 Medicare patients from 26 California counties between 2001 and 2011.

Main outcome measures

(1) Access to hospitals with cardiac technology; (2) treatment received; and (3) health outcomes (30-day, 90-day, and 1-year death and 30-day readmission).

Results

Hospitals serving high volume of black patients spent more hours in diversion status compared with other hospitals. Patients faced with the highest level of diversion had the lowest probability of being admitted to hospitals with cardiac technology compared with those facing no diversion, by 4.4% for cardiac care intensive unit, and 3.4% for catheterisation laboratory and coronary artery bypass graft facilities. Patients experiencing increased diversion also had a 4.3% decreased likelihood of receiving catheterisation and 9.6% higher 1-year mortality.

Conclusions

Hospitals serving high volume of black patients are more likely to be on diversion, and diversion is associated with poorer access to cardiac technology, lower probability of receiving revascularisation and worse long-term mortality outcomes.
Global issues put a new perspective on working life
Authors: Subirana Josep
Published: March 2016

Having worked in general practice, Josep Subirana decided to broaden his experience in animal welfare and get involved in international development. Since then, he has worked across the world helping charities, universities and organisations with animal welfare issues
Ten‐minute chat
Authors: Scudamore Cheryl
Published: March 2016

In her second year of vet school Cheryl Scudamore found she enjoyed pathology and biological research and decided that practice might not be for her. Now working in biomedical science as a pathologist she supports studies into the genetic basis of human diseases.
Separability of M-Equivalent Words by Morphisms
Authors: Teh Wen Chean
Published: March 2016

Two words are M-equivalent iff they are indistinguishable by Parikh matrices. Even for the ternary alphabet, an incontestable characterization of the M-equivalence relation is long overdue, ever since the introduction of Parikh matrices by Mateescu et al. in 2001. Recent works by Atanasiu attempted to distinguish M-equivalent words by the Parikh matrices of their images under some morphism. This paper addresses various aspects of this approach. In particular, it is shown that no morphism is capable of completely separating M-equivalent words over a given alphabet. However, if the class of words is restricted in length, then such morphism exists, whose codomain is connected to the notion of t-spectrum.
A Novel Approach to Optimize Fault-Tolerant Hybrid Wireless Network-on-Chip Architectures
Authors: Dehghani Abbas , Jamshidi Kamal
Published: March 2016

Wireless Network-on-Chip (WNoC) architectures have emerged as a promising interconnection infrastructure to address the performance limitations of traditional wire-based multihop NOCs. Nevertheless, the WNoC systems encounter high failure rates due to problems pertaining to integration and manufacturing of wireless interconnection in nano-domain technology. As a result, the permanent failures may lead to the formation of any shape of faulty regions in the interconnection network, which can break down the whole system. This issue is not investigated in previous studies on WNoC architectures. Our solution advocates the adoption of communication structures with both node and link on disjoint paths. On the other hand, the imposed costs of WNoC design must be reasonable. Hence, a novel approach to design an optimized fault-tolerant hybrid hierarchical WNoC architecture for enhancing performance as well as minimizing system costs is proposed. The experimental results indicate that the robustness of this newly proposed design is significantly enhanced in comparison with its the fault-tolerant wire-based counterparts in the presence of various faulty regions under both synthetic and application-specific traffic patterns.
An Integrated Exploration and Virtual Platform Framework for Many-Accelerator Heterogeneous Systems
Authors: Sotiriou-Xanthopoulos Efstathios , Xydis Sotirios , Siozios Kostas , Economakos George , Soudris Dimitrios
Published: March 2016

The recent advent of many-accelerator systems-on-chip (SoC), driven by the need for maximizing throughput and power efficiency, has led to an exponential increase in the hardware/software co-design complexity. The reason of this increase is that the designer has to explore a vast number of architectural parameter combinations for each single accelerator, as well as inter-accelerator configuration combinations under specific area, throughput, and power constraints, given that each accelerator has different computational requirements. In such a case, the design space size explodes. Thus, existing design space exploration (DSE) techniques give poor-quality solutions, as the design space cannot be adequately covered in a fair time. This problem is aggravated by the very long simulation time of the many-accelerator virtual platforms (VPs). This article addresses these design issues by (a) presenting a virtual prototyping solution that decreases the exploration time by enabling the evaluation of multiple configurations per VP simulation and (b) proposing a DSE methodology that efficiently explores the design space of many-accelerator systems. With the use of two fully developed use cases, namely an H.264 decoding server for multiple video streams and a parallelized denoising system for MRI scans, we show that the proposed DSE methodology either leads to Pareto points that dominate over those of a typical DSE scenario or finds new solutions that might not be found by the typical DSE. In addition, the proposed virtual prototyping solution leads to DSE runtime reduction reaching 10 × for H.264 and 5 × for Rician denoise.
Unified Medium Access Control Architecture for Resource-Constrained Machine-to-Machine Devices
Authors: Kim Eui-Jik , Kwon Jung-Hyok , Choi Ken , Shon Taeshik
Published: March 2016

In capillary machine-to-machine (M2M) communications, which is being considered as a feasible network solution for M2M applications, because of physical resource constraints and deployment conditions, an energy-efficient and scalable medium access control (MAC) protocol is crucial for numerous M2M devices to concurrently access wireless channels. Therefore, this paper presents a unified MAC layer architecture for resource-constrained M2M devices in capillary M2M networks [named as resource-constrained MAC architecture (RCMA)], which has a unified (monolithic) framework consisting of essential functional components to support MAC-related operations of M2M devices: multi-channel hybrid MAC (McHM), logical link control (LLC), time synchronizer (TS), and device on--off scheduler (DO2S). McHM provides a baseline MAC protocol for an entire capillary M2M system that combines the benefit of both contention-based carrier sense multiple access and schedule-based time division multiple access schemes, whereas the other three components help in the McHM operations. To demonstrate the effectiveness of the RCMA, we implement the whole stack using the QualNet simulator. Experimental results show that the RCMA outperforms the conventional ZigBee stack in terms of energy efficiency and scalability, even under heavy traffic conditions.
ENFrame
Authors: Olteanu Dan , Schaik Sebastiaan J. Van
Published: March 2016

This article introduces ENFrame, a framework for processing probabilistic data. Using ENFrame, users can write programs in a fragment of Python with constructs such as loops, list comprehension, aggregate operations on lists, and calls to external database engines. Programs are then interpreted probabilistically by ENFrame. We exemplify ENFrame on three clustering algorithms (
k
-means,
k
-medoids, and Markov clustering) and one classification algorithm (
k
-nearest-neighbour).

A key component of ENFrame is an event language to succinctly encode correlations, trace the computation of user programs, and allow for computation of discrete probability distributions for program variables. We propose a family of sequential and concurrent, exact, and approximate algorithms for computing the probability of interconnected events. Experiments with
k
-medoids clustering and
k
-nearest-neighbour show orders-of-magnitude improvements of exact processing using ENFrame over naïve processing in each possible world, of approximate over exact, and of concurrent over sequential processing.
The Rise of Computational Biology
Authors: Tichy Walter
Published: March 2016

In this wide-ranging interview, we will hear from a pioneer in computational biology on where the field stands and on where it is going. The topics stretch from gene sequencing and protein structure prediction, all the way to personalized medicine and cell regulation. We'll find out how bioinformatics uses a data-driven approach and why personal drugs may become affordable. We'll even discuss whether we will be able to download our brains into computers and live forever.
When Do Noisy Votes Reveal the Truth?
Authors: Caragiannis Ioannis , Procaccia Ariel D. , Shah Nisarg
Published: March 2016

A well-studied approach to the design of voting rules views them as maximum likelihood estimators; given votes that are seen as noisy estimates of a true ranking of the alternatives, the rule must reconstruct the most likely true ranking. We argue that this is too stringent a requirement and instead ask:how manyvotes does a voting rule need to reconstruct the true ranking? We define the family ofpairwise-majority consistentrules and show that for all rules in this family, the number of samples required from Mallows’s noise model is logarithmic in the number of alternatives, and that no rule can do asymptotically better (while some rules like plurality do much worse). Taking a more normative point of view, we consider voting rules that surely return the true ranking as the number of samples tends to infinity (we call this propertyaccuracy in the limit); this allows us to move to a higher level of abstraction. We study families of noise models that are parameterized by distance functions and find voting rules that are accurate in the limit for all noise models in such general families. We characterize the distance functions that induce noise models for which pairwise-majority consistent rules are accurate in the limit and provide a similar result for another novel family ofposition-dominance consistentrules. These characterizations capture three well-known distance functions.
Assets 2015
Authors: Yesilada Yeliz , Bigham Jeffrey
Published: March 2016

This year was the 17th edition of the ACM SIGACCESS International Conference on Computers and Accessibility (ASSETS 2015)
1
. ASSETS 2015 took place in Lisbon, which is the capital of Portugal and is known as the city of seven hills (A Cidade das Sete Colinas). The conference was very well attended around 170 participants from all over the world. There was one keynote speech by Jon Schull from Rochester Institute of Technology and e-NABLE. The best paper award went to "Understanding the Challenges Faced by Neurodiverse Software Engineering Employees: Towards a More Inclusive and Productive Technical Workforce" by Meredith Ringel Morris, Andrew Begel and Ben Weidermann. The best student paper award went to "Social Media Platforms for Low-Income Blind People in India" by Aditya Vashistha, Edward Cutrell, Nicola Dell, and Richard Anderson. The conference also had an excellent social program having drinks and nice food in the evenings, which was great to meet people and socialise with the accessibility community.
Digital and tactile drawing-system for blind users
Authors: Bornschein Jens
Published: March 2016

In my PhD-Task I want to allow blind users to create digital drawings on their own and, in particular, support tactile drawing by fingers. As the common mechanisms for creating tactile graphics by blind people are analog or text-based methods, editing graphics is a hard or nearly impossible task. I want to build a system that allows a blind user to create tactile graphics with intuitive interaction methods, such as drawing with the fingers, drawing with a pen as well as using stamps and tangibles. Technically this can be realized with a digitalization pen, a standard consumer time of flight (TOF) camera system for input and a two-dimensional touch-sensitive tactile pin-matrix device for output. With this system blind users will get for the first time the freedom of their own digital pictorial expression with all the benefits of digital drawing tools that visual users have for several decades.
Supporting inclusive and collaborative postsecondary education for adults with intellectual disabilities
Authors: Buehler Erin
Published: March 2016

Persons with disabilities face obstacles to education and employment that are both social and systemic. With rising demand for postsecondary degrees and technical skills for hourly and entry-level jobs, access to technology education is crucial. My previous and proposed research explores technology education for adults with intellectual disabilities in the context of 3D modeling and printing. Using the lens of this emergent technology, I have identified potential teaching and learning techniques that can be incorporated into an inclusive technology intervention for individualized instruction design.
Improving the senior wellbeing through telehealth support and integrated care
Authors: Rodolfo Inês
Published: March 2016

Along with aging, technological changes are felt as a way to assist, maintain and extend life. Assistive technology allows people to stay comfortable in their homes increasing their sense of confidence and security. The research reported here has the goal to empower seniors on their daily lives. We designed a proposal for an Integrated Personal Health Record for the improvement of a Nation-wide Patient Portal. We also involved the project stakeholders of the Portal on a user-centered design process to engage new users into the platform. Currently, we are exploring the design of an online channel for a recently launched National Telehealth Senior Program. Seniors have the potential of interacting with both systems and have an integrated view over their health; access their medical records and geriatric assessments; use online healthcare services e.g., scheduling appointments; finally, contribute with self-collected data such as observations of the daily living to monitor their health and provide more patient knowledge to healthcare providers.
Two desirable fairness concepts for allocation of indivisible objects under ordinal preferences
Authors: Aziz Haris , Gaspers Serge , Mackenzie Simon , Walsh Toby
Published: March 2016

Fair allocation of indivisible objects under ordinal preferences is an important problem. Unfortunately, a fairness notion like envy- freeness is both incompatible with Pareto optimality and is also NP-complete to achieve. To tackle this predicament, we consider a different notion of fairness, namely proportionality. We frame allocation of indivisible objects as randomized assignment but with integrality requirements. We then use the stochastic dominance relation to define two natural notions of proportionality. Since an assignment may not exist even for the weaker notion of proportionality, we propose relaxations of the concepts --- optimal weak proportionality and optimal proportionality. For both concepts, we propose algorithms to compute fair assignments under ordinal preferences. Both new fairness concepts appear to be desirable in view of the following: they are compatible with Pareto optimality, admit efficient algorithms to compute them, are based on proportionality, and are guaranteed to exist.
2016 travel grant program awards
Authors: Settle Amber
Published: March 2016

The SIGCSE Board is pleased to announce the recipients of the 2016 Travel Grant Program awards. The Travel Grant Program was created thanks to the generosity of Henry Walker and provides faculty and teachers who have not previously attended the Symposium with up to $500 in travel support to do so. This cycle there were twenty applications, from which six awards were given.
SIGCSE Symposium 2016 preview
Authors: Alphonce Carl , Tims Jodi
Published: March 2016

Memphis, Tennessee, home of Graceland, Sun Studios, the National Civil Rights Museum, and, of course, the Peabody ducks, sits on the banks of the Mississippi river. Like the mighty Mississippi, which combines the waters of hundreds of tributaries in one massive flow that nourishes countless souls with its rich waters, so the SIGCSE Technical Symposium gathers ideas, techniques, tools and more to engage, energize and empower computer science educators from far and wide. Just a few steps from the river of so many tales and songs, the 2016 SIGCSE Symposium promises to be an event to remember. Alongside the usual offering of papers, panels, special sessions, workshops, birds-of-a-feather (BOFs), posters, lightning talks and demos, there is an assortment of pre-symposium and affiliated events, including the student research competition and talks by our marvelous lineup of keynote and plenary speakers. Our exhibit hall will feature both familiar faces and newcomers and will provide valuable information and resources for computer science education.
Member spotlight
Authors: Kauchak David
Published: March 2016

In this feature of the Bulletin, we highlight members of the SIGCSE community. In this issue, Bulletin co-editor David Kauchak interviewed John Impagliazzo, Professor Emeritus at Hofstra University and former ACM Inroads editor.
Inhibition of pancreatic acinar mitochondrial thiamin pyrophosphate uptake by the cigarette smoke component 4-(methylnitrosamino)-1-(3-pyridyl)-1-butanone
Authors: Srinivasan Padmanabhan , Thrower Edwin C. , Gorelick Fred S. , Said Hamid M.
Published: March 2016

Thiamin is essential for normal metabolism in pancreatic acinar cells (PAC) and is obtained from their microenvironment through specific plasma-membrane transporters, converted to thiamin pyrophosphate (TPP) in the cytoplasm, followed by uptake of TPP by mitochondria through the mitochondrial TPP (MTPP) transporter (MTPPT; product of SLC25A19 gene). TPP is essential for normal mitochondrial function. We examined the effect of long-term/chronic exposure of PAC in vitro (pancreatic acinar 266-6 cells) and in vivo (wild-type or transgenic mice carrying the SLC25A19 promoter) of the cigarette smoke toxin, 4-(methylnitrosamino)-1-(3-pyridyl)-1-butanone (NNK), on the MTPP uptake process. Our in vitro and in vivo findings demonstrate that NNK negatively affects MTPP uptake and reduced expression of MTPPT protein, MTPPT mRNA, and heterogenous nuclear RNA, as well as SLC25A19 promoter activity. The effect of NNK on Slc25a19 transcription was neither mediated by changes in expression of transcriptional factor NFY-1 (known to drive SLC25A19 transcription), nor due to changes in methylation profile of the Slc25a19 promoter. Rather, it appears to be due to changes in histone modifications that involve significant decreases in histone H3K4-trimethylation and H3K9-acetylation (activation markers). The effect of NNK on MTPPT function is mediated through the nonneuronal α7-nicotinic acetylcholine receptor (α7-nAChR), as indicated by both in vitro (using the nAChR antagonist mecamylamine) and in vivo (using an α7-nAchR −/− mouse model) studies. These findings demonstrate that chronic exposure of PAC to NNK negatively impacts PAC MTPP uptake. This effect appears to be exerted at the level of Slc25a19 transcription, involve epigenetic mechanism(s), and is mediated through the α7-nAchR.
Combining Epigenetic and Immunotherapy to Combat Cancer
Authors: Chiappinelli Katherine B. , Zahnow Cynthia A. , Ahuja Nita , Baylin Stephen B.
Published: March 2016

The most exciting recent advance for achieving durable management of advanced human cancers is immunotherapy, especially the concept of immune checkpoint blockade. However, with the exception of melanoma, most patients do not respond to immunotherapy alone. A growing body of work has shown that epigenetic drugs, specifically DNA methyltransferase inhibitors, can upregulate immune signaling in epithelial cancer cells through demethylation of endogenous retroviruses and cancer testis antigens. These demethylating agents may induce T-cell attraction and enhance immune checkpoint inhibitor efficacy in mouse models. Current clinical trials are testing this combination therapy as a potent new cancer management strategy. Cancer Res; 76(7); 1683–9. ©2016 AACR.
CD70 Exacerbates Blood Pressure Elevation and Renal Damage in Response to Repeated Hypertensive Stimuli
Authors: Itani Hana A. , Xiao Liang , Saleh Mohamed A. , Wu Jing , Pilkinton Mark A. , Dale Bethany L. , Barbaro Natalia R. , Foss Jason D. , Kirabo Annet , Montaniel Kim R. , Norlander Allison E. , Chen Wei , Sato Ryosuke , Navar L. Gabriel , Mallal Simon A. , Madhur Meena S. , Bernstein Kenneth E. , Harrison David G.
Published: March 2016

Rationale:

Accumulating evidence supports a role of adaptive immunity and particularly T cells in the pathogenesis of hypertension. Formation of memory T cells, which requires the costimulatory molecule CD70 on antigen-presenting cells, is a cardinal feature of adaptive immunity.

Objective:

To test the hypothesis that CD70 and immunologic memory contribute to the blood pressure elevation and renal dysfunction mediated by repeated hypertensive challenges.

Methods and Results:

We imposed repeated hypertensive challenges using either
N
ω
-nitro-L-arginine methyl ester hydrochloride (L-NAME)/high salt or repeated angiotensin II stimulation in mice. During these challenges effector memory T cells (T

EM

) accumulated in the kidney and bone marrow. In the L-NAME/high-salt model, memory T cells of the kidney were predominant sources of interferon-γ and interleukin-17A, known to contribute to hypertension. L-NAME/high salt increased macrophage and dendritic cell surface expression of CD70 by 3- to 5-fold. Mice lacking CD70 did not accumulate T

EM

cells and did not develop hypertension to either high salt or the second angiotensin II challenge and were protected against renal damage. Bone marrow–residing T

EM

cells proliferated and redistributed to the kidney in response to repeated salt feeding. Adoptively transferred T

EM

cells from hypertensive mice homed to the bone marrow and spleen and expanded on salt feeding of the recipient mice.

Conclusions:

Our findings illustrate a previously undefined role of CD70 and long-lived T

EM

cells in the development of blood pressure elevation and end-organ damage that occur on delayed exposure to mild hypertensive stimuli. Interventions to prevent repeated hypertensive surges could attenuate formation of hypertension-specific T

EM

cells.
Cotton Micronaire Measurements Using Small Portable Near-Infrared (NIR) Analyzers
Authors: Zumba Jimmy , Rodgers James
Published: March 2016

A key quality and processing parameter for cotton fiber is micronaire, which is a function of the fiber's maturity and fineness. Near-infrared (NIR) spectroscopy has previously shown the ability to measure micronaire, primarily in the laboratory and using large, research-grade laboratory NIR instrumentation. International interest has been expressed by the industry in the measurement of fiber micronaire using small, portable NIR spectroscopy instruments for both laboratory and outside the laboratory (e.g., field or greenhouse) locations. New, very small NIR micro-spectrometers have been commercialized that offer the potential advantages of smaller size and lower weight, lower cost, and increased portability over current portable units. A program was implemented to determine the feasibility of a small NIR micro-spectrometer to measure fiber micronaire both in the laboratory and outside the laboratory, with initial emphasis on laboratory measurements prior to moving to field evaluations. In the laboratory, distinct spectral differences with increasing micronaire were observed. Optimal sampling and instrumental procedures and protocols for two units (different spectral wavelength capabilities) were established. Comparative evaluations established very good method micronaire agreement between the micro-spectrometer and a standard portable spectrometer, with high Regression (R) value, low residuals, and few outliers (less than 20%). The NIR micro-spectrometer measurements were fast (<1 min per sample), required no sample preparation, and were easy to perform. All end-state criteria were exceeded. The rapid and accurate laboratory measurement of fiber micronaire with a NIR micro-spectrometer was demonstrated.
Police supervisors' work-related attitudes in China
Authors: Liu Jianhong , Sun Ivan Y , Wu Yuning , Chang Yugang
Published: March 2016

While the past two decades have witnessed a fast growing of policing literature in China, officers' job-related attitudes remain severely under-researched. Using survey data collected from 212 police supervisors in a major Chinese city, this study examined the patterns of Chinese police officers' occupational attitudes toward selective enforcement, legal restrictions, community policing, and use of force, and factors that influence such attitudes. About half the respondents were in favor of legal restrictions, and the majority of officers supported the notions of selective enforcement, community policing, and use of force. Male, older officers, those who had no military experience, and officers who worked at field stations favored selective enforcement than their counterparts, whereas supervisor who were younger and worked at nonfield stations were more supportive for legal restrictions. Supervisors' role orientations toward law enforcement and order maintenance influenced their preference for community policing. Implications for future research and policy were discussed.
Using Complementary Learning Clusters in Studying Literature to Enhance Students' Medical Humanities Literacy, Critical Thinking, and English Proficiency
Authors: Liao Hung-Chang , Wang Ya-Huei
Published: March 2016

This study examined whether students studying literature in complementary learning clusters would show more improvement in medical humanities literacy, critical thinking skills, and English proficiency compared to those in conventional learning clusters. Ninety-three students participated in the study ( M age = 18.2 years, SD = 0.4; 36 men, 57 women). A quasi-experimental design was used over 16 weeks, with the control group ( n = 47) working in conventional learning clusters and the experimental group ( n = 46) working in complementary learning clusters. Complementary learning clusters were those in which individuals had complementary strengths enabling them to learn from and offer assistance to other cluster members, hypothetically facilitating the learning process. Measures included the Medical Humanities Literacy Scale, Critical Thinking Disposition Assessment, English proficiency tests, and Analytic Critical Thinking Scoring Rubric. The results showed that complementary learning clusters have the potential to improve students’ medical humanities literacy, critical thinking skills, and English proficiency.
Down by the Riverside
Authors: Anderson Celia Rousseau , Dixson Adrienne D.
Published: March 2016

In this article, the authors utilize core ideas from Critical Race Theory (CRT) to examine the nature of education reform in two river cities. Similar to other cases of education reform in urban districts, the reforms in the two focal cities reflect at least four characteristics in common: (1) a form of portfolio management; (2) the growth of human-capital organizations; (2) the active involvement of philanthropic organizations; and (4) the role of politics. The authors consider these conditions in light of concepts from CRT and argue that this analysis provides insight into the burden of reform in urban schools.
Contextualization is complicated: A case study of contextualized worship arts in Mozambique
Authors: Meyers Megan
Published: March 2016

The enormous demographic change of Christianity worldwide is forcing a reexamination of basic questions about Christian identity and the relation of local Christian communities to other Christian groups and traditions. Christianity has been both an agent and a product of the flattening and shrinking of the world. What are the implications of globalization for contextualized worship arts? Through an ethnographic study of 12 urban churches, conducted from 2012 to 2014 in Beira, Mozambique, this article explores the challenges of globalization for developing contextualized worship arts.
Effectively Working With Military Linguists
Authors: Hajjar Remi M.
Published: March 2016

This article examines the relationship between advisors and linguists in the contemporary military advising mission and applies an emergent postmodern military culture theoretical framework. This project’s multimethod collected data from Iraq, documents, and interviews. The study reveals an intriguing and nuanced story about the deployment of advisors and linguists in the advising mission. This article defines the military advising mission including the major actors. The article then introduces the postmodern military culture theoretical framework and method. The findings report many themes including linguist selection and hiring processes, the importance of advisor–linguist relationships, the relevance of linguists’ backgrounds, linguists as full advisory team members, and the building blocks of successful advising sessions. Effective advisors work with linguists to deploy a Swiss Army knife of cultural tools including peacekeeper diplomat, warrior, subject matter expert, innovator, and others to accomplish the mission, which divulge broader changes indicative of an emergent postmodern military and culture.
Effect of virtual reality exposure and aural stimuli on eye contact, directional focus, and focus of attention of novice wind band conductors
Authors: Orman Evelyn K.
Published: March 2016

This study examined the effects of virtual reality immersion with audio on eye contact, directional focus and focus of attention for novice wind band conductors. Participants ( N = 34) included a control group ( n = 12) and two virtual reality groups with ( n = 10) and without ( n = 12) head tracking. Participants completed conducting/score study sessions twice a week for four weeks. Individual videotaped conducting sessions of a live ensemble before and after treatment served as pre and posttest measures. No significant ( p > 0.05) changes due to virtual reality immersion were found. Further analyses with a larger dataset ( N = 68) showed those working with audio ( n = 34) significantly increased ( p < 0.05) eye contact for the fast portion of the musical selection. Findings indicate (a) a sense of reality is created during virtual reality immersion and (b) the use of sound during score study may be beneficial for increasing conductor eye contact.
Classification of spondylolytic clefts in patients with spondylolysis or isthmic spondylolisthesis using positional MRI
Authors: Niggemann Pascal , Kuchta Johannes , Hadizadeh Dariusch , Pieper Claus Christian , Schild Hans Heinz
Published: March 2016

Background

Posterior instability is a pathologic movement occurring in the spondylolytic cleft.

Purpose

To present a new classification system for the evaluation of spondylolytic cleft by positional magnetic resonance imaging (MRI) and determine the prevalence of the different types.

Material and Methods

A total of 176 segments of the lumbar spine with spondylolysis or isthmic spondylolisthesis were examined using positional MRI. Scans were obtained in neutral sitting, flexion, and extension positions. No visible movement in the cleft was defined as type A, fluid displaced into the cleft as type BI, displacement of the flava ligaments at the level of the cleft as type BII, and intraspinal cysts arising from the spondylolytic cleft as type BIII. The movements were characterized by a radiologist and a neurosurgeon experienced in positional MRI. Clinical findings were correlated with the different types of instability.

Results

A high agreement was found between the two observers. In total, 131 segments were characterized as type A, six as type BI, 24 as type BII, and 10 as type BIII. In five segments, the type differed between the right and the left side. Two patients had a mixed type BI/II, another two patients had a mixed type BII/III, and one patient had a mixed type BI/III. Patients with type BII and BIII instabilities suffered more often from radicular symptoms compared to patients without any instability.

Conclusion

The presented classification might help to better understand and study changes encountered in the spondylolytic cleft in patients with spondylolysis and isthmic spondylolisthesis using positional MRI.
Impact on Hip Fracture Mortality After the Establishment of an Orthogeriatric Care Program in a Colombian Hospital
Authors: Suarez Sebastian , Pesantez Rodrigo Fernando , Diaz Mario Enrique , Sanchez Daniela , Tristancho Lady Johana , Vanegas Maria Victoria , Olarte Carlos Mario
Published: March 2016

Objective: The aim of this study is to evaluate mortality and survival rates of patients aged 65 years or older who sustained a hip fracture and were treated at a hospital in Bogotá, Colombia, after the establishment of an Orthogeriatric Program. Method: In total, 298 patients were treated according to the program’s protocol. The primary outcome was 1-year mortality. Mortality predictors were estimated using Cox proportional hazards model, and survival was measured with Kaplan–Meier analysis. Results: The annual survival rate increased from 80% to 89% ( p = .039) 4 years after its implementation. There was a significant decrease in mortality risk (Hazard Ratio = 0.54, p = .049). Arrhythmia, valvular heart disease, history of myocardial infarction, and age greater than 85 years were predictors of mortality. Discussion: This is the first study in Latin America to show decreased mortality rates 1 year after the implementation of an Orthogeriatric Program. Our rates were lower than developed countries, suggesting the existence of additional factors that influence long-term outcomes.