bluuebunny/crossref_metadata_2025 huggingface dataset:
Identification of biologic agents to neutralize the bicomponent leukocidins of
Staphylococcus aureus
Authors: Chan Rita , Buckley Peter T. , O’Malley Aidan , Sause William E. , Alonzo Francis , Lubkin Ashira , Boguslawski Kristina M. , Payne Angela , Fernandez Jeffrey , Strohl William R. , Whitaker Brian , Lynch Anthony Simon , Torres Victor J.
Published: January 2019

Small protein biologics called centyrins can be engineered to combat the toxicity caused by systemic
Staphylococcus aureus
infection.
Improved Performance of a Rapid Immunochromatographic Assay for Detection of PBP2a in Non-Staphylococcus aureus Staphylococcal Species
Authors: Canver Matthew C. , Gonzalez Mark D. , Ford Bradley A. , Arnold Amanda R. , Lawhon Sara D. , Burnham Carey-Ann D. , Jenkins Stephen G. , Burd Eileen M. , Westblade Lars F.
Published: January 2019

Non-
Staphylococcus aureus
staphylococcal species (non-SASS) are important pathogens in both animal and human populations. The development of β-lactam resistance in non-SASS through acquisition and expression of penicillin-binding protein 2a (PBP2a) represents a significant clinical and public health threat.
Vaccination of Icelandic Children with the 10-Valent Pneumococcal Vaccine Leads to a Significant Herd Effect among Adults in Iceland
Authors: Quirk Sigríður J. , Haraldsson Gunnsteinn , Hjálmarsdóttir Martha Á. , van Tonder Andries J. , Hrafnkelsson Birgir , Bentley Stephen D. , Haraldsson Ásgeir , Erlendsdóttir Helga , Brueggemann Angela B. , Kristinsson Karl G.
Published: January 2019

The introduction of pneumococcal conjugate vaccines (PCVs) into childhood vaccination programs has reduced carriage of vaccine serotypes and pneumococcal disease. The 10-valent PCV was introduced in Iceland in 2011.
Paediatrician’s guide to epigenetics
Authors: Byrne Lauren , Drake Amanda Jane
Published: January 2019

Epigenetic regulation of gene expression is critical for normal development. Dysregulation of the epigenome can lead to the development and progression of a number of diseases relevant to paediatricians, including disorders of genomic imprinting and malignancies. It has long been recognised that early life events have implications for future disease risk, and epigenetic modifications may play a role in this, although further high-quality research is needed to better understand the underlying mechanisms. Research in the field of epigenetics will contribute to a greater understanding of growth, development and disease; however, paediatricians need to be able to interpret such research critically, in order to use the potential advances brought about through epigenetic studies while appreciating their limitations.
Global health security and universal health coverage: from a marriage of convenience to a strategic, effective partnership
Authors: Wenham Clare , Katz Rebecca , Birungi Charles , Boden Lisa , Eccleston-Turner Mark , Gostin Lawrence , Guinto Renzo , Hellowell Mark , Onarheim Kristine Husøy , Hutton Joshua , Kapilashrami Anuj , Mendenhall Emily , Phelan Alexandra , Tichenor Marlee , Sridhar Devi
Published: January 2019

Global health security and universal health coverage have been frequently considered as “two sides of the same coin”. Yet, greater analysis is required as to whether and where these two ideals converge, and what important differences exist. A consequence of ignoring their individual characteristics is to distort global and local health priorities in an effort to streamline policymaking and funding activities. This paper examines the areas of convergence and divergence between global health security and universal health coverage, both conceptually and empirically. We consider analytical concepts of risk and human rights as fundamental to both goals, but also identify differences in priorities between the two ideals. We support the argument that the process of health system strengthening provides the most promising mechanism of benefiting both goals.
Cell therapy for ARDS: efficacy of endobronchial versus intravenous administration and biodistribution of MAPCs in a large animal model
Authors: Cardenes Nayra , Aranda-Valderrama Paola , Carney Jonathan P , Sellares Torres Jacobo , Alvarez Diana , Kocyildirim Ergin , Wolfram Smith Julie A , Ting Antony E , Lagazzi Luigi , Yu Zheming , Mason Scott , Santos Ernesto , Lopresti Brian J , Rojas Mauricio
Published: January 2019

Introduction

Bone marrow-derived multipotent adult progenitor cells (MAPCs) are adult allogeneic adherent stem cells currently investigated clinically for use in acute respiratory distress syndrome (ARDS). To date, there is no agreement on which is the best method for stem cells delivery in ARDS. Here, we compared the efficacy of two different methods of administration and biodistribution of MAPC for the treatment of ARDS in a sheep model.

Methods

MAPC were labelled with [18F] fluoro-29-deoxy-D-glucose and delivered by endobronchial (EB) or intravenous route 1 hour after lipopolysaccharide infusion in sheep mechanically ventilated. PET/CT images were acquired to determine the biodistribution and retention of the cells at 1 and 5 hours of administration.

Results

The distribution and retention of the MAPC was dependent on the method of cell administration. By EB route, PET images showed that MAPC remained at the site of administration and no changes were observed after 5 hours, whereas with intravenous route, the cells had broad biodistribution to different organs, being the lung the main organ of retention at 1 and 5 hours. MAPC demonstrated an equal effect on arterial oxygenation recovery by either route of administration.

Conclusion

The EB or intravenous routes of administration of MAPC are both effective for the treatment of ARDS in an acute sheep model, and the effect of MAPC therapy is not dependent of parenchymal integration or systemic biodistribution.
Which parameters to use for sleep quality monitoring in team sport athletes? A systematic review and meta-analysis
Authors: Claudino João Gustavo , J Gabbett Tim , de Sá Souza Helton , Simim Mário , Fowler Peter , de Alcantara Borba Diego , Melo Marco , Bottino Altamiro , Loturco Irineu , D’Almeida Vânia , Carlos Amadio Alberto , Cerca Serrão Julio , P Nassis George
Published: January 2019

Background

Sleep quality is an essential component of athlete’s recovery. However, a better understanding of the parameters to adequately quantify sleep quality in team sport athletes is clearly warranted.

Objective

To identify which parameters to use for sleep quality monitoring in team sport athletes.

Methods

Systematic searches for articles reporting the qualitative markers related to sleep in team sport athletes were conducted in PubMed, Scopus, SPORTDiscus and Web of Science online databases. The systematic review followed the Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines. For the meta-analysis, effect sizes with 95% CI were calculated and heterogeneity was assessed using a random-effects model. The coefficient of variation (CV) with 95% CI was also calculated to assess the level of instability of each parameter.

Results

In general, 30 measuring instruments were used for monitoring sleep quality. A meta-analysis was undertaken on 15 of these parameters. Four objective parameters inferred by actigraphy had significant results (sleep efficiency with small CV and sleep latency, wake episodes and total wake episode duration with large CV). Six subjective parameters obtained from questionnaires and scales also had meaningful results (Pittsburgh Sleep Quality Index (sleep efficiency), Likert scale (Hooper), Likert scale (no reference), Liverpool Jet-Lag Questionnaire, Liverpool Jet-Lag Questionnaire (sleep rating) and RESTQ (sleep quality)).

Conclusions

These data suggest that sleep efficiency using actigraphy, Pittsburgh Sleep Quality Index, Likert scale, Liverpool Jet-Lag Questionnaire and RESTQ are indicated to monitor sleep quality in team sport athletes.

PROSPERO registration number

CRD42018083941.
Accuracy of a point-of-care test for quantifying human chorionic gonadotrophin (hCG) in the management of pregnancy of unknown location in an abortion service
Authors: Reynolds-Wright John Joseph , Main Peter , Cameron Sharon T
Published: January 2019

Introduction

Women may seek abortion at gestations when there is no visible intrauterine pregnancy on ultrasound scanning. Clinical protocols for pregnancy of unknown location (PUL) require measurement of serum human chorionic gonadotrophin (hCG), with the National Institute for Health and Care Excellence recommending that values above 1500 IU/L be further investigated to exclude ectopic pregnancy. Our aim was to determine whether a point-of-care test (POCT) could be used instead of laboratory serum hCG measurement.

Methods

Over 12 months, women who presented to an abortion service with a PUL had a POCT for blood or urine hCG and laboratory serum hCG measurement. The POCT machine used provides a discrete hCG value below 1000 IU/L and above this gives results as a range. The sensitivity and specificity of the POCT in identifying cases where laboratory serum hCG results were above 1500 IU/L were calculated.

Results

A total of 118 women presented with a PUL, of whom 70 had a POCT on blood (n=49) or urine (n=21) and a corresponding laboratory serum hCG. The sensitivity of the blood POCT was 0.67 (95% CI 0.38 to 0.87) and the specificity was 0.97 (95% CI 0.83 to 0.99). The sensitivity of the urine POCT was 0.25 (CI 0.01 to 0.78) and the specificity was 0.94 (CI 0.69 to 0.99).

Conclusion

Although both the blood and urine POCTs had a high level of specificity, neither test was acceptably sensitive. While promising, this POCT for hCG is not sufficiently reliable to replace laboratory serum hCG testing in the management of women with PUL in an abortion service.
Update on eighth edition American Joint Committee on Cancer classification for Merkel cell carcinoma and histopathological parameters that determine prognosis
Authors: Trinidad Celestine M , Torres-Cabala Carlos A , Prieto Victor G , Aung Phyu P
Published: January 2019

Merkel cell carcinoma (MCC) is a rare primary cutaneous neuroendocrine carcinoma. The annual incidence of MCC is increasing in the USA. Timely diagnosis and proper staging of this tumour are crucial as MCC has high rates of regional recurrence and lymph node and distant metastasis. In this review, we outline the key differences between the tumor node metastasis (TNM) staging criteria for MCC in the seventh and eighth editions of theAJCC Cancer Staging Manual. We also discuss histopathological parameters that are not included in the eighth edition of the manual but have been shown in other studies to predict a worse prognosis in patients with MCC. Correct assessment and reporting of these clinically relevant histopathological parameters is of utmost importance for practising pathologists as management differs according to the stage of the tumour. This review aims to increase awareness of all these parameters, and proper recognition would guide the treating clinicians towards the most appropriate treatment options that can be given to patients.
Comparison of fingolimod, dimethyl fumarate and teriflunomide for multiple sclerosis
Authors: Kalincik Tomas , Kubala Havrdova Eva , Horakova Dana , Izquierdo Guillermo , Prat Alexandre , Girard Marc , Duquette Pierre , Grammond Pierre , Onofrj Marco , Lugaresi Alessandra , Ozakbas Serkan , Kappos Ludwig , Kuhle Jens , Terzi Murat , Lechner-Scott Jeannette , Boz Cavit , Grand'Maison Francois , Prevost Julie , Sola Patrizia , Ferraro Diana , Granella Franco , Trojano Maria , Bergamaschi Roberto , Pucci Eugenio , Turkoglu Recai , McCombe Pamela A , Pesch Vincent Van , Van Wijmeersch Bart , Solaro Claudio , Ramo-Tello Cristina , Slee Mark , Alroughani Raed , Yamout Bassem , Shaygannejad Vahid , Spitaleri Daniele , Sánchez-Menoyo José Luis , Ampapa Radek , Hodgkinson Suzanne , Karabudak Rana , Butler Ernest , Vucic Steve , Jokubaitis Vilija , Spelman Tim , Butzkueven Helmut
Published: January 2019

Objective

Oral immunotherapies have become a standard treatment in relapsing-remitting multiple sclerosis. Direct comparison of their effect on relapse and disability is needed.

Methods

We identified all patients with relapsing-remitting multiple sclerosis treated with teriflunomide, dimethyl fumarate or fingolimod, with minimum 3-month treatment persistence and disability follow-up in the global MSBase cohort study. Patients were matched using propensity scores. Three pairwise analyses compared annualised relapse rates and hazards of disability accumulation, disability improvement and treatment discontinuation (analysed with negative binomial models and weighted conditional survival models, with pairwise censoring).

Results

The eligible cohorts consisted of 614 (teriflunomide), 782 (dimethyl fumarate) or 2332 (fingolimod) patients, followed over the median of 2.5 years. Annualised relapse rates were lower on fingolimod compared with teriflunomide (0.18 vs 0.24; p=0.05) and dimethyl fumarate (0.20 vs 0.26; p=0.01) and similar on dimethyl fumarate and teriflunomide (0.19 vs 0.22; p=0.55). No differences in disability accumulation (p≥0.59) or improvement (p≥0.14) were found between the therapies. In patients with ≥3-month treatment persistence, subsequent discontinuations were less likely on fingolimod than teriflunomide and dimethyl fumarate (p<0.001). Discontinuation rates on teriflunomide and dimethyl fumarate were similar (p=0.68).

Conclusion

The effect of fingolimod on relapse frequency was superior to teriflunomide and dimethyl fumarate. The effect of the three oral therapies on disability outcomes was similar during the initial 2.5 years on treatment. Persistence on fingolimod was superior to the two comparator drugs.
Validation studies of virtual reality simulation performance metrics for mechanical thrombectomy in ischemic stroke
Authors: Crossley Robert , Liebig Thomas , Holtmannspoetter Markus , Lindkvist Johan , Henn Pat , Lonn Lars , Gallagher Anthony Gerald
Published: January 2019

Introduction

Mechanical thrombectomy (MT) has transformed the treatment of ischemic stroke. However, patient access to MT may be limited due to a shortage of doctors specifically trained to perform MT. The studies reported here were done to (1) develop, operationally define, and seek consensus from procedure experts on the metrics which best characterize a reference procedure for the performance of an MT for ischemic stroke and (2) evaluate their construct validity when implemented in a virtual reality (VR) simulation.

Methods

In study 1, the metrics for a reference approach to an MT procedure for ischemic stroke of 10 phases, 46 steps, and 56 errors and critical errors, were presented to an international Delphi panel of 21 consultant level interventional neuroradiologists (INRs). In study 2, the metrics were used to assess 8 expert and 10 novice INRs performing a VR simulated routine MT procedure.

Results

In study 1, the Delphi panel reached consensus on the appropriateness of the procedure metrics for a reference approach to MT in ischemic stroke. Group differences in median scores in study 2 demonstrated that experienced INRs performed the case 19% faster (P=0.029), completed 40% more procedure phases (P=0.009), 20% more steps (P=0.012), and made 42% fewer errors (P=0.016) than the novice group.

Conclusions

The international Delphi panel agreed metrics implemented in a VR simulation of MT distinguished between the computer scored procedure performance of INR experts and novices. The studies reported here support the demonstration of face, content, and construct validity of the MT metrics.
Lead intoxication mimicking idiopathic epilepsy in a young dog
Authors: Liatis Theophanes , Monti Paola , Latre Ariadna Ribas , Mantis Panagiotis , Cherubini Giunio Bruto
Published: January 2019

An 11‐month‐old neutered female cocker spaniel was referred for two generalised tonic‐clonic epileptic seizures with a one‐week interval of mild depression. On admission, physical and neurological examinations were unremarkable. Neurolocalisation was forebrain. Haematology, biochemistry, serology for infectious diseases, urinalysis and urine culture were unremarkable. Cerebral MRI revealed T1‐weighted hyperintensity in the lentiform nuclei. Cerebrospinal fluid analysis was unremarkable. Idiopathic epilepsy was mistakenly diagnosed and phenobarbital was started. A delayed blood film examination revealed metarubricytosis, polychromasia and basophilic stippling, raising the suspicion of lead intoxication. Abdominal radiography revealed a metallic lead foreign body (lead curtain weight), which removed endoscopically. Treatment with CaEDTA, thiamine and D‐penicillamine was started. This report highlights the importance of including haematology, blood smear examination, biochemistry and urinalysis in the diagnostic workup of acute epileptic seizures particularly in young dogs. Lead intoxication should be included in the differential diagnosis in these patients, as modern lead sources still exist in our environment.
Dispersive property of the quantum vacuum and the speed of light
Authors: Razmi H. , Baramzadeh N. , Baramzadeh H.
Published: January 2019

We want to study the influence of the quantum vacuum on light propagation. At first, by working in the standard linear quantum theory of the electromagnetic fields, it is shown that the electric permittivity and the magnetic permeability of the vacuum medium are changed; but, the resulting speed of light is not modified. Then, taking into account nonlinear effects by considering the Euler–Heisenberg Lagrangian, the corresponding zero point (vacuum) energy and the resulting modification of the speed of light are found up to the first nonvanishing correction.
Energy critical Schrödinger equation with weighted exponential nonlinearity: Local and global well-posedness
Authors: Bensouilah Abdelwahab , Draouil Dhouha , Majdoub Mohamed
Published: January 2019

We investigate the initial value problem for a defocusing nonlinear Schrödinger equation with weighted exponential nonlinearity [Formula: see text] where [Formula: see text] and [Formula: see text]. We establish local and global well-posedness in the subcritical and critical regimes.
Assessing mineral fertility and bias in sedimentary provenance studies: examples from the Barents Shelf
Authors: Flowerdew Michael J. , Fleming Edward J. , Morton Andrew C. , Frei Dirk , Chew David M. , Daly J. Stephen
Published: January 2019

The development of laser ablation techniques using inductively coupled plasma mass spectrometry has enabled the routine and fast acquisition of
in situ
U–Pb and Pb–Pb isotope ratio data from single detrital grains or parts of grains. Detrital zircon dating is a technique that is increasingly applied to sedimentary provenance studies. However, sand routing information using zircon analysis alone may be obscured by repeated sedimentary reworking cycles and mineral fertility variations. These biases are illustrated by two clear case studies from the Triassic–Jurassic of the Barents Shelf where the use of U–Pb geochronology on apatite and rutile and Pb–Pb isotopic data from K-feldspar is highly beneficial for provenance interpretations. In the first case study, U–Pb apatite ages from the (Induan – Norian) Havert, Kobbe and Snadd formations indicate an evolving provenance and identify possible episodes of storage within foreland basins prior to delivery onto the Barents Shelf. In the second case study, U–Pb rutile and Pb isotopic analyses of K-feldspar from the Norian–Pliensbachian Realgrunnen Subgroup provide a clear distinction between north Norwegian Caledonides and Fennoscandian Shield sources and suggest that a similar approach may be used to test competing models for sand dispersal for this Subgroup in regions farther north than this study.
Bootstrapped Graph Diffusions
Authors: Buchnik Eliav , Cohen Edith
Published: January 2019

Graph-based semi-supervised learning (SSL) algorithms predict labels for all nodes based on provided labels of a small set of seed nodes. Classic methods capture the graph structure through some underlying diffusion process that propagates through the graph edges. Spectral diffusion, which includes personalized page rank and label propagation, propagates through random walks. Social diffusion propagates through shortest paths. These diffusions are linear in the sense of not distinguishing between contributions of few "strong" relations or many "weak'' relations. Recent methods such as node embeddings and graph convolutional networks (GCN) attained significant gains in quality for SSL tasks. These methods vary on how the graph structure, seed label information, and other features are used, but do share a common thread of nonlinearity that suppresses weak relations and re-enforces stronger ones. Aiming for quality gain with more scalable methods, we revisit classic linear diffusion methods and place them in a self-training framework. The resulting bootstrapped diffusions are nonlinear in that they re-enforce stronger relations, as with the more complex methods. Surprisingly, we observe that SSL with bootstrapped diffusions not only significantly improves over the respective non-bootstrapped baselines but also outperform state-of-the-art SSL methods. Moreover, since the self-training wrapper retains the scalability of the base method, we obtain both higher quality and better scalability.
SOAP
Authors: Scully Ziv , Harchol-Balter Mor , Scheller-Wolf Alan
Published: January 2019

We consider an extremely broad class of M/G/1 scheduling policies called SOAP: Schedule Ordered by Age-based Priority. The SOAP policies include almost all scheduling policies in the literature as well as an infinite number of variants which have never been analyzed, or maybe not even conceived. SOAP policies range from classic policies, like first-come, first-serve (FCFS), foreground-background (FB), class-based priority, and shortest remaining processing time (SRPT); to much more complicated scheduling rules, such as the famously complex Gittins index policy and other policies in which a job's priority changes arbitrarily with its age. While the response time of policies in the former category is well understood, policies in the latter category have resisted response time analysis. We present a universal analysis of all SOAP policies, deriving the mean and Laplace-Stieltjes transform of response time. The full version of this work appears in POMACS [Scully et al., 2018].
Hound
Authors: Zheng Pengfei , Lee Benjamin C.
Published: January 2019

Stragglers are exceptionally slow tasks within a job that delay its completion. Stragglers, which are uncommon within a single job, are pervasive in datacenters with many jobs. We present Hound, a statistical machine learning framework that infers the causes of stragglers from traces of datacenter-scale jobs. Hound is designed to achieve several objectives: datacenter-scale diagnosis, unbiased inference, interpretable models, and computational efficiency. We demonstrate Hound's capabilities for a production trace from Google's warehouse-scale datacenters and two Spark traces from Amazon EC2 clusters.
On Non-Preemptive VM Scheduling in the Cloud
Authors: Psychas Konstantinos , Ghaderi Javad
Published: January 2019

We study the problem of scheduling VMs (Virtual Machines) in a distributed server platform, motivated by cloud computing applications. The VMs arrive dynamically over time to the system, and require a certain amount of resources (e.g. memory, CPU, etc) for the duration of their service. To avoid costly preemptions, we consider non-preemptive scheduling: Each VM has to be assigned to a server which has enough residual capacity to accommodate it, and once a VM is assigned to a server, its service cannot be disrupted (preempted). Prior approaches to this problem either have high complexity, require synchronization among the servers, or yield queue sizes/delays which are excessively large. We propose a non-preemptive scheduling algorithm that resolves these issues. In general, given an approximation algorithm to Knapsack with approximation ratio r , our scheduling algorithm can provide rβ fraction of the throughput region for β < r. In the special case of a greedy approximation algorithm to Knapsack, we further show that this condition can be relaxed to β<1. The parameters β and r can be tuned to provide a tradeoff between achievable throughput, delay, and computational complexity of the scheduling algorithm. Finally extensive simulation results using both synthetic and real traffic traces are presented to verify the performance of our algorithm.
Network Resilience and the Length-Bounded Multicut Problem
Authors: Kuhnle Alan , Crawford Victoria G. , Thai My T.
Published: January 2019

Motivated by networked systems in which the functionality of the network depends on vertices in the network being within a bounded distance T of each other, we study the length-bounded multicut problem: given a set of pairs, find a minimum-size set of edges whose removal ensures the distance between each pair exceeds T . We introduce the first algorithms for this problem capable of scaling to massive networks with billions of edges and nodes: three highly scalable algorithms with worst-case performance ratios. Furthermore, one of our algorithms is fully dynamic, capable of updating its solution upon incremental vertex / edge additions or removals from the network while maintaining its performance ratio. Finally, we show that unless NP ⊆ BPP, there is no polynomial-time, approximation algorithm with performance ratio better than Omega (T), which matches the ratio of our dynamic algorithm up to a constant factor.
Neural Network Meets DCN
Authors: Wang Mowei , Cui Yong , Xiao Shihan , Wang Xin , Yang Dan , Chen Kai , Zhu Jun
Published: January 2019

The emerging optical/wireless topology reconfiguration technologies have shown great potential in improving the performance of data center networks. However, it also poses a big challenge on how to find the best topology configurations to support the dynamic traffic demands. In this work, we present xWeaver, a traffic-driven deep learning solution to infer the high-performance network topology online. xWeaver supports a powerful network model that enables the topology optimization over different performance metrics and network architectures. With the design of properly-structured neural networks, it can automatically derive the critical traffic patterns from data traces and learn the underlying mapping between the traffic patterns and topology configurations specific to the target data center. After offline training, xWeaver generates the optimized (or near-optimal) topology configuration online, and can also smoothly update its model parameters for new traffic patterns. The experiment results show the significant performance gain of xWeaver in supporting smaller flow completion time.
The CSI Framework for Compiler-Inserted Program Instrumentation
Authors: Schardl Tao B. , Denniston Tyler , Doucet Damon , Kuszmaul Bradley C. , Lee I-Ting Angelina , Leiserson Charles E.
Published: January 2019

The CSI framework provides comprehensive static instrumentation that a compiler can insert into a program-under-test so that dynamic-analysis tools - memory checkers, race detectors, cache simulators, performance profilers, code-coverage analyzers, etc. - can observe and investigate runtime behavior. Heretofore, tools based on compiler instrumentation would each separately modify the compiler to insert their own instrumentation. In contrast, CSI inserts a standard collection of instrumentation hooks into the program-under-test. Each CSI-tool is implemented as a library that defines relevant hooks, and the remaining hooks are "nulled" out and elided during either compile-time or link-time optimization, resulting in instrumented runtimes on par with custom instrumentation. CSI allows many compiler-based tools to be written as simple libraries without modifying the compiler, lowering the bar for the development of dynamic-analysis tools. We have defined a standard API for CSI and modified LLVM to insert CSI hooks into the compiler's internal representation (IR) of the program. The API organizes IR objects - such as functions, basic blocks, and memory accesses - into flat and compact ID spaces, which not only simplifies the building of tools, but surprisingly enables faster maintenance of IR-object data than do traditional hash tables. CSI hooks contain a "property" parameter that allows tools to customize behavior based on static information without introducing overhead. CSI provides "forensic" tables that tools can use to associate IR objects with source-code locations and to relate IR objects to each other. To evaluate the efficacy of CSI, we implemented six demonstration CSI-tools. One of our studies shows that compiling with CSI and linking with the "null" CSI-tool produces a tool-instrumented executable that is as fast as the original uninstrumented code. Another study, using a CSI port of Google's ThreadSanitizer, shows that the CSI-tool rivals the performance of Google's custom compiler-based implementation. All other demonstration CSI tools slow down the execution of the program-under-test by less than 70%.
A Refined Mean Field Approximation
Authors: Gast Nicolas , Van Houdt Benny
Published: January 2019

Stochastic models have been used to assess the performance of computer (and other) systems for many decades. As a direct analysis of large and complex stochastic models is often prohibitive, approximations methods to study their behavior have been devised. One very popular approximation method relies on mean field theory. Its widespread use can be explained by the relative ease involved to define and solve a mean field model in combination with its high accuracy for large systems.
REACT to Cyber-Physical Attacks on Power grids (Extended Abstract)
Authors: Soltan Saleh , Yannakakis Mihalis , Zussman Gil
Published: January 2019

We study cyber attacks on power grids that affect both the physical infrastructure and the data at the control center? which therefore are cyber-physical in nature. In particular, we assume that an adversary attacks an area by: (i) remotely disconnecting some lines within the attacked area, and (ii) modifying the information received from the attacked area to mask the line failures and hide the attacked area from the control center. For the latter, we consider two types of attacks: (i) data distortion: which distorts the data by adding powerful noise to the actual data, and (ii) data replay: which replays a locally consistent old data instead of the actual data. We use the DC power flow model and prove that the problem of finding the set of line failures given the phase angles of the nodes outside of the attacked area is strongly NP-hard, even when the attacked area is known. However, we introduce the polynomial time REcurrent Attack Containment and deTection (REACT) Algorithm to approximately detect the attacked area and line failures after a cyber-physical attack.
Adaptive Strategic Cyber Defense for Advanced Persistent Threats in Critical Infrastructure Networks
Authors: Huang Linan , Zhu Quanyan
Published: January 2019

Advanced Persistent Threats (APTs) have created new security challenges for critical infrastructures due to their stealthy, dynamic, and adaptive natures. In this work, we aim to lay a game-theoretic foundation by establishing a multi-stage Bayesian game framework to capture incomplete information of deceptive APTs and their multistage multi-phase movement. The analysis of the perfect Bayesian Nash equilibrium (PBNE) enables a prediction of attacker's behaviors and a design of defensive strategies that can deter the adversaries and mitigate the security risks. A conjugate-prior method allows online computation of the belief and reduces Bayesian update into an iterative parameter update. The forwardly updated parameters are assimilated into the backward dynamic programming computation to characterize a computationally tractable and timeconsistent equilibrium solution based on the expanded state space. The Tennessee Eastman (TE) process control problem is used as a case study to demonstrate the dynamic game under the information asymmetry and show that APTs tend to be stealthy and deceptive during their transitions in the cyber layer and behave aggressively when reaching the targeted physical plant. The online update of the belief allows the defender to learn the behavior of the attacker and choose strategic defensive actions that can thwart adversarial behaviors and mitigate APTs. Numerical results illustrate the defender's tradeoff between the immediate reward and the future expectation as well as the attacker's goal to reach an advantageous system state while making the defender form a positive belief.
Evaluating Local Disaster Recovery Strategies
Authors: Oostenbrink Jorik , Kuipers Fernando A. , Heegaard Poul E. , Helvik Bjarne E.
Published: January 2019

It is of vital importance to maintain at least some network functionality after a disaster, for example by temporarily replacing damaged nodes by emergency nodes. We propose a framework to evaluate different node replacement strategies, based on a large set of representative disasters.

We prove that computing the optimal choice of nodes to replace is an NP-hard problem and propose several simple strategies. We evaluate these strategies on two U.S. topologies and show that a simple greedy strategy can perform close to optimal.
Special Issue on the Work-in-Progress (WIP) session at the ACM SIGMETRICS 2018 Conference
Authors: Liu Zhenhua , Ananthanarayanan Ganesh
Published: January 2019

The ACM SIGMETRICS 2018 conference was held in Irvine, CA, USA. For the first time, we organized the Work-in-Progress (WIP) session. This session provided a great opportunity to present earlystage research to receive valuable feedback from the community through a dedicated poster session.

Topics fell within the purview of the SIGMETRICS main conference. Within these topics, we particularly encouraged (but were not limited to) submissions that are pursuing new, perhaps controversial, directions. We also welcomed submissions of posters corresponding to results presented at the SIGMETRICS-affiliated workshops.

Anewcategory of posterswe introduced, unlike poster sessions at other conferences, is about systems published at related conference venues (such as SOSP, SIGCOMM, NSDI) that could benefit froma thorough analytical modeling. Thework in conferences like SOSP, SIGCOMM and NSDI tend to focus on the systemic architecture but often do not do a thorough job of analytically grounding their solutions. For submissions in this category, we asked the authors to clearly explain why the poster is relevant to the SIGMETRICS community.

Submissions were judged based on their novelty as well as the potential to generate discussions. Eleven submissionswere accepted with attendance from USA and Asia. Topics range from cloud computing, power systems, security, to vehicular caching.
Convex Prophet Inequalities
Authors: Qin Junjie , Rajagopal Ram , Vardi Shai , Wierman Adam
Published: January 2019

We introduce a new class of prophet inequalities-convex prophet inequalities-where a gambler observes a sequence of convex cost functions ci (xi ) and is required to assign some fraction 0 ≤ xi ≤ 1 to each, such that the sum of assigned values is exactly 1. The goal of the gambler is to minimize the sum of the costs. We provide an optimal algorithm for this problem, a dynamic program, and show that it can be implemented in polynomial time when the cost functions are polynomial. We also precisely characterize the competitive ratio of the optimal algorithm in the case where the gambler has an outside option and there are polynomial costs, showing that it grows as !(np-1/ζ), where n is the number of stages, p is the degree of the polynomial costs and the coefficients of the cost functions are bounded by [`,u].
HappyFeet
Authors: Md Faridee Abu Zaher , Ramamurthy Sreenivasan Ramasamy , Roy Nirmalya
Published: January 2019

In this paper, we discuss our experience in building an automated dance assessment tool with IMU and IoT devices and highlight the major challenges of such an endeavor. In a typical dance classroom scenario, where the students frequently outnumber their instructors, such a system can add an immense value to both parties by providing systematic breakdown of the dance moves, comparing the dance moves between the students and the instructors, and pinpointing the places for improvement in an autonomous way. Along that direction, our prototypical work, HappyFeet [1], showcases our initial attempts of developing such an intelligent Dance Activity Recognition (DAR) system. Our CNN based Body Sensor Network proves more effective (by ≈7% margin at 94.20%) at accurately recognizing the micro-steps of the dance activities than traditional feature engineering approaches. These metrics are derived by purposely evaluating the setup on a dance form known for its gentle, smooth and subtle limb movements. In this paper, we articulate how our proposed DAR framework will be generalizable for diverse dance styles involving very pronounced movements, human body kinematics and energy profiles.
Research on ARM TrustZone
Authors: Li Wenhao , Xia Yubin , Chen Haibo
Published: January 2019

ARM TrustZone [1] is a hardware-based security feature that can provide software with a high-privilege and isolated execution environment. Such isolation is ensured by hardware, which is usually considered as more trustworthy than software. Thus the execution environment is also known as trusted execution environment (TEE). TrustZone technology was proposed in 2002, but did not get widely used until 2009, when Apple released iPhone 5s. In iPhone 5s, Apple leveraged TrustZone to protect its Touch ID, which ensures that even if the iOS is fully compromised, the user's fingerprint data can still be safe. In 2017, Google made TEE a mandatory requirement on any Android devices with a fingerprint scanner. Nowadays, almost all mobile phones and tablets have TEE deployed. Meanwhile, ARM integrates TrustZone in ARM64 and ARMv8-M to support a broader range of platforms including servers and IoT devices.
Ultra-Low-Power Gaze Tracking for Virtual Reality
Authors: Li Tianxing , Liu Qiang , Zhou Xia
Published: January 2019

LiGaze is a low-cost, low-power approach to gaze tracking tailored to virtual reality (VR). It relies on a few low-cost photodiodes, eliminating the need for cameras and active infrared emitters. Reusing light from the VR screen, LiGaze leverages photodiodes around a VR lens to measure reflected screen light in different directions. It then infers gaze direction by exploiting the pupil's light absorption property. The core of LiGaze is to deal with screen light dynamics and extract changes in reflected light related to pupil movement. LiGaze infers a 3D gaze vector on the fly using a lightweight regression algorithm. Compared to the eye tracker of an existing VR headset (FOVE), LiGaze achieves 6.3° and 10.1° mean within-user and cross-user accuracy. Its sensing and computation consume 791 W in total and thus can be completely powered by a credit card-size solar cell harvesting energy from indoor lighting. LiGaze's simplicity and ultra-low power make it applicable in a wide range of VR headsets to better unleash VR's potential.
LiveTag
Authors: Gao Chuhan , Li Yilong , Zhang Xinyu
Published: January 2019

Information about the objects a person touches is an essential input to many applications in ubiquitous computing. The ability to sense touch in the physical world can form the basis of the tangible user interface [1], which allows humans to use omnipresent objects as a command-and-control interface to the digital world. On the other hand, the sequence of objects used can enable inference of human activities. Post-processing of this information can support many activity-aware applications, such as stroke rehabilitation assessment in homes, consumer analytics for retail stores, etc.
ACM SIGIR Annual Business Meeting 2018
Authors: Yilmaz Emine
Published: January 2019

The 2018 ACM SIGIR Annual Business Meeting took place on Wednesday July 11, 2018, at the SIGIR'18 Conference in Ann Arbor, Michigan, USA. The meeting was held between 13:00-14:30 and was led by the chair of SIGIR Executive Committee, Diane Kelly.

The meeting started with an introduction to the executive committee, which involves Diane Kelly (University of Tennessee) as the chair, Jaap Kamps (University of Amsterdam) as the vice chair, Emine Yilmaz (University College London) as the secretary, Ben Carterette (University of Delaware) as the treasurer and Charles Clarke (University of Waterloo) as the past chair. Apart from the executive committee, volunteers play an important role in running SIGIR. Diane introduced and thanked the volunteers for 2017-2018. The volunteers for this period were Nattiya Kanhabua & Guido Zuccon (Information Directors), Jaime Arguello (Student Travel Awards Chair), Craig Macdonald (June Forum Editor), Claudia Hauff (December Forum editor), Falk Scholer (Awards Chair), Laura Dietz (Student Affairs Chair), Yoelle Maarek (Industy Liaison), Jimmy Lin (CIKM Conference Liaison), Sue Dumais (WSDM Conference Liaison) and Edie Rasmussen (JCDL Conference Liaison).

The upcoming year is an election year for the SIGIR Executive Committee. As part of this, new elections will be done for the chair, vice chair, secretary and treasurer positions. This year the committee also introduces a new volunteer position, the Diversity, Equity and Inclusion Chair whose role will be to increase diversity and inclusion at SIGIR. This position will also be filled for the upcoming year. Alistair Moffat will be leading the election process as the Election Official.
Autumn School for Information Retrieval and Information Foraging (ASIRF 2017)
Authors: Dodson Samuel , Zimmerman Steven
Published: January 2019

The Autumn School for Information Retrieval and Information Foraging (ASIRF) was held October 1-6, 2017 in Wadern, Germany. The school provided students with a review of topics in information retrieval and information behavior through lectures, student presentations, and a student project. ASIRF attracted thirty-one participants, from Asia, Europe, and North and South America.
Building Community
Authors: Fails Jerry Alan , Pera Maria Soledad , Kucirkova Natalia
Published: January 2019

We discuss the outcomes of the 2nd Workshop of the International and Interdisciplinary Perspectives on Children & Recommender Systems (KidRec 2018), co-located with the 2018 ACM Interaction Design and Children (IDC) Conference, which took place June 19-22 in Trondheim, Norway. The goal for this workshop was to explore research and industry efforts focused directly on or facilitating the algorithmic recommendation process for children. The diversity of attendees including K-12 teachers, educators, researchers in various areas of computer science, and industry participants-made it possible to continue to build community around this important topic and further discuss and outline the salient research questions and the next steps to promote more research in this area.
Report on the Eighth International Workshop on Location and the Web (LocWeb 2018)
Authors: Ahlers Dirk , Wilde Erik , Schifanella Rossano , Alowibdi Jalal S.
Published: January 2019

LocWeb 2018 continued the LocWeb workshop series at the intersection of location-based services and Web architecture and was held at The Web Conference, WWW 2018. It focused on Web-scale services and systems facilitating location-aware information access as well as on Spatial Social Behavior Analytics on the Web as part of social computing. The LocWeb 2018 workshop had contributions ranging from location data analysis over tourism and virtual reality up to societal engagement. This report briefly presents the theme, contributions, and discussions of the workshop.
Acute and chronic changes in the control of breathing in a rat model of bronchopulmonary dysplasia
Authors: Mouradian Gary C. , Alvarez-Argote Santiago , Gorzek Ryan , Thuku Gabriel , Michkalkiewicz Teresa , Wong-Riley Margaret T. T. , Konduri Girija Ganesh , Hodges Matthew R.
Published: January 2019

Infants born very prematurely (<28 wk gestation) have immature lungs and often require supplemental oxygen. However, long-term hyperoxia exposure can arrest lung development, leading to bronchopulmonary dysplasia (BPD), which increases acute and long-term respiratory morbidity and mortality. The neural mechanisms controlling breathing are highly plastic during development. Whether the ventilatory control system adapts to pulmonary disease associated with hyperoxia exposure in infancy remains unclear. Here, we assessed potential age-dependent adaptations in the control of breathing in an established rat model of BPD associated with hyperoxia. Hyperoxia exposure ([Formula: see text]; 0.9 from 0 to 10 days of life) led to a BPD-like lung phenotype, including sustained reductions in alveolar surface area and counts, and modest increases in airway resistance. Hyperoxia exposure also led to chronic increases in room air and acute hypoxic minute ventilation (V̇e) and age-dependent changes in breath-to-breath variability. Hyperoxia-exposed rats had normal oxygen saturation ([Formula: see text]) in room air but greater reductions in [Formula: see text] during acute hypoxia (12% O2) that were likely due to lung injury. Moreover, acute ventilatory sensitivity was reduced at P12 to P14. Perinatal hyperoxia led to greater glial fibrillary acidic protein expression and an increase in neuron counts within six of eight or one of eight key brainstem regions, respectively, controlling breathing, suggesting astrocytic expansion. In conclusion, perinatal hyperoxia in rats induced a BPD-like phenotype and age-dependent adaptations in V̇e that may be mediated through changes to the neural architecture of the ventilatory control system. Our results suggest chronically altered ventilatory control in BPD.
Three classical papers in respiratory physiology by Christian Bohr (1855–1911) whose work is frequently cited but seldom read
Authors: West John B.
Published: January 2019

History has been kind to Christian Bohr (1855–1911). His name is attached eponymously to three different areas of respiratory physiology. The first is the Bohr dead space, which refers to the portion of the tidal volume that does not undergo gas exchange. The second is the increase in oxygen affinity of hemoglobin caused by the addition of carbon dioxide to the blood. This is known as the Bohr effect and is a very important feature of gas exchange, both in the lung and in peripheral tissues. Both of these contributions by Bohr are familiar to most students. Bohr’s third contribution refers to the calculation of the changes in the Po2 of blood as oxygen is loaded in the pulmonary capillary, the so-called Bohr integration. This contribution is less well known now, partly because of the advent of digital computing, but it was important in its day. The analysis is challenging because the very nonlinear shape of the oxygen dissociation curve means that the Po2 difference between the alveolar gas and the capillary blood, which is the driving pressure for diffusion, changes in a complicated way. All three papers are in German, and two of them are long and tedious to read. English translations are available, but few people read the papers, despite the fact that the first two articles are very frequently cited. In the present article, Bohr’s contributions are reviewed, and some parts of the articles that are particularly difficult to understand are clarified.