bluuebunny/crossref_metadata_2025_split huggingface dataset:
Virtual ghost
Authors: Criswell John , Dautenhahn Nathan , Adve Vikram 
Published: April 2020

Applications that process sensitive data can be carefully designed and validated to be difficult to attack, but they are usually run on monolithic, commodity operating systems, which may be less secure. An OS compromise gives the attacker complete access to all of an application's data, regardless of how well the application is built. We propose a new system, Virtual Ghost, that protects applications from a compromised or even hostile OS. Virtual Ghost is the first system to do so by combining compiler instrumentation and run-time checks on operating system code, which it uses to create ghost memory that the operating system cannot read or write. Virtual Ghost interposes a thin hardware abstraction layer between the kernel and the hardware that provides a set of operations that the kernel must use to manipulate hardware, and provides a few trusted services for secure applications such as ghost memory management, encryption and signing services, and key management. Unlike previous solutions, Virtual Ghost does not use a higher privilege level than the kernel.
Virtual Ghost performs well compared to previous approaches; it outperforms InkTag on five out of seven of the LMBench microbenchmarks with improvements between 1.3x and 14.3x. For network downloads, Virtual Ghost experiences a 45% reduction in bandwidth at most for small files and nearly no reduction in bandwidth for large files and web traffic. An application we modified to use ghost memory shows a maximum additional overhead of 5% due to the Virtual Ghost protections. We also demonstrate Virtual Ghost's efficacy by showing how it defeats sophisticated rootkit attacks.
Resolved
Authors: Wood David A. 
Published: April 2020

The field of computing has struggled since its inception with the tension between specialization and generalization. Specialized architectures, programming languages, and system software promise better performance (across many metrics, including efficiency, productivity, etc.) for workloads that match their specialization objective. General-purpose architectures, languages, and system software sacrifice extremes of performance for specific workloads, seeking acceptable performance across a much wider range. While specialized alternatives have always had their place, general-purpose architectures, languages, and system software have dominated main-stream computing systems for the past several decades. But with Dennard scaling already gone and the end of Moore's Law looming, some have argued that general-purpose computing platforms must naturally give way to specialization.
In this debate, two teams of highly-opinionated experts will debate the proposition that specialized architectures, languages, and system software should largely supplant general-purpose alternatives within the next decade. Arguments in favor of specialization include energy efficiency in the post-Dennard scaling era, performance scaling in the post-Moore's law era, and improvements in programmer productivity. Arguments against include the large investment needed to create specialized hardware and software components, lack of tools and interfaces to create reusable components, the semantic gap from overspecialization, and security vulnerabilities and general correctness issues due to interoperation of specialized components.
Secure and Durable (SEDURA)
Authors: Liu Chen , Yang Chengmo 
Published: April 2020

Phase changing memory (PCM) is considered a promising candidate for next-generation main-memory. Despite its advantages of lower power and high density, PCM faces critical security challenges due to its non-volatility: data are still accessible by the attacker even if the device is detached from a power supply. While encryption has been widely adopted as the solution to protect data, it not only creates additional performance and energy overhead during data encryption/decryption, but also hurts PCM lifetime by introducing more writes to PCM cells.
In this paper, we propose a framework that integrates encryption and wear-leveling so as to mitigate the adverse impact of encryption on PCM performance and lifetime. Moreover, by randomizing the address space during wear-leveling, an extra level of protection is provided to the data in memory. We propose two algorithms that respectively prioritize data security and memory lifetime, allowing designers to trade-off between these two factors based on their needs. Compared to previous encryption techniques, the proposed SEDURA framework is able to deliver both more randomness to protect data and more balanced PCM writes, thus effectively balancing the three aspects of data security, application performance, and device lifetime.
TrilobiteG
Authors: Woithe Hans Christian , Kremer Ulrich 
Published: April 2020

Programming autonomous systems can be challenging because many programming decisions must be made in real time and under stressful conditions, such as on a battle field, during a short communication window, or during a storm at sea. As such, new programming designs are needed to reflect these specific and extreme challenges.
TrilobiteG is a programming architecture for buoyancy-driven autonomous underwater vehicles (AUVs), called gliders. Gliders are designed to spend weeks to months in the ocean, where they operate fully autonomously while submerged and can only communicate via satellite during their limited time at the surface. Based on the experience gained from a seven year long collaboration with two oceanographic institutes, the TrilobiteG architecture has been developed with the main goal of enabling users to run more effective missions. The TrilobiteG programming environment consists of a domain-specific language called ALGAE, a lower level service layer, and a set of real-time and faster-than-real-time simulators. The system has been used to program novel and robust glider behaviors, as well as to find software problems that otherwise may have remained undetected, with potentially catastrophic results. We believe that TrilobiteG can serve as a blueprint for other autonomous systems as well, and that TrilobiteG will motivate and enable a broader scientific community to work on extreme, real-world problems by using the simulation infrastructure.
Characterizing Output Bottlenecks of a Production Supercomputer
Authors: Xie Bing , Oral Sarp , Zimmer Christopher , Choi Jong Youl , Dillow David , Klasky Scott , Lofstead Jay , Podhorszki Norbert , Chase Jeffrey S. 
Published: April 2020

This article studies the I/O write behaviors of the Titan supercomputer and its Lustre parallel file stores under production load. The results can inform the design, deployment, and configuration of file systems along with the design of I/O software in the application, operating system, and adaptive I/O libraries.
We propose a statistical benchmarking methodology to measure write performance across I/O configurations, hardware settings, and system conditions. Moreover, we introduce two relative measures to quantify the write-performance behaviors of hardware components under production load. In addition to designing experiments and benchmarking on Titan, we verify the experimental results on one real application and one real application I/O kernel, XGC and HACC IO, respectively. These two are representative and widely used to address the typical I/O behaviors of applications.
In summary, we find that Titan’s I/O system is variable across the machine at fine time scales. This variability has two major implications. First, stragglers lessen the benefit of coupled I/O parallelism (striping). Peak median output bandwidths are obtained with parallel writes to many independent files, with no striping or write sharing of files across clients (compute nodes). I/O parallelism is most effective when the application—or its I/O libraries—distributes the I/O load so that each target stores files for multiple clients and each client writes files on multiple targets in a balanced way with minimal contention. Second, our results suggest that the potential benefit of dynamic adaptation is limited. In particular, it is not fruitful to attempt to identify “good locations” in the machine or in the file system: component performance is driven by transient load conditions and past performance is not a useful predictor of future performance. For example, we do not observe diurnal load patterns that are predictable.
A Formal Approach to Physics-based Attacks in Cyber-physical Systems
Authors: Lanotte Ruggero , Merro Massimo , Munteanu Andrei , Viganò Luca 
Published: April 2020

We apply formal methods to lay and streamline theoretical foundations to reason about Cyber-Physical Systems (CPSs) and physics-based attacks, i.e., attacks targeting physical devices. We focus on a formal treatment of both integrity and denial of service attacks to sensors and actuators of CPSs, and on the timing aspects of these attacks. Our contributions are fourfold. (1) We define a hybrid process calculus to model both CPSs and physics-based attacks. (2) We formalise a threat model that specifies MITM attacks that can manipulate sensor readings or control commands to drive a CPS into an undesired state; we group these attacks into classes and provide the means to assess attack tolerance/vulnerability with respect to a given class of attacks, based on a proper notion of most powerful physics-based attack. (3) We formalise how to estimate the impact of a successful attack on a CPS and investigate possible quantifications of the success chances of an attack. (4) We illustrate our definitions and results by formalising a non-trivial running example in U
PPAAL
SMC, the statistical extension of the U
PPAAL
model checker; we use U
PPAAL
SMC as an automatic tool for carrying out a static security analysis of our running example in isolation and when exposed to three different physics-based attacks with different impacts.
Discriminative Power of Typing Features on Desktops, Tablets, and Phones for User Identification
Authors: Belman Amith K. , Phoha Vir V. 
Published: April 2020

Research in Keystroke-Dynamics (KD) has customarily focused on temporal features without considering context to generate user templates that are used in authentication. Additionally, work on KD in hand-held devices such as smart-phones and tablets have shown that these features alone do not perform satisfactorily for authentication. In this work, we analyze the discriminatory power of the most-used conventional features found in the literature, propose a set of context-sensitive or word-specific features, and analyze the discriminatory power of proposed features using their classification results. To perform these tasks, we use the keystroke data consisting of over 650K keystrokes, collected from 20 unique users during different activities on desktops, tablets, and phones, over a span of two months. On an average, each user made 12.5K, 9K, and 10K keystrokes on desktop, tablet, and phone, respectively.
We find that the conventional features are not highly discriminatory on desktops and are only marginally better on hand-held devices for user identification. By using information of the context, a subset (derived after analysis) of our proposed word-specific features offers superior discrimination among users on all devices. We find that a majority of the classifiers, built using these features, perform user identification well with accuracies in the range of 90% to 97%, average precision and recall values of 0.914 and 0.901, respectively, on balanced test samples in 10-fold cross validation. We also find that proposed features work best on hand-held devices. This work calls for a shift from using conventional KD features to a set of context-sensitive or word-specific KD features that take advantage of known information such as context.
Stress‐Induced Cyclin C Translocation Regulates Cardiac Mitochondrial Dynamics
Authors: Ponce Jessica M. , Coen Grace , Spitler Kathryn M. , Dragisic Nikola , Martins Ines , Hinton Antentor , Mungai Margaret , Tadinada Satya Murthy , Zhang Hao , Oudit Gavin Y. , Song Long‐Sheng , Li Na , Sicinski Peter , Strack Stefan , Abel E. Dale , Mitchell Colleen , Hall Duane D. , Grueter Chad E. 
Published: April 2020

Background
Nuclear‐to‐mitochondrial communication regulating gene expression and mitochondrial function is a critical process following cardiac ischemic injury. In this study, we determined that cyclin C, a component of the Mediator complex, regulates cardiac and mitochondrial function in part by modifying mitochondrial fission. We tested the hypothesis that cyclin C functions as a transcriptional cofactor in the nucleus and a signaling molecule stimulating mitochondrial fission in response to stimuli such as cardiac ischemia.

Methods and Results

We utilized gain‐ and loss‐of‐function mouse models in which the
CCNC
(cyclin C) gene was constitutively expressed (transgenic, CycC cTg) or deleted (knockout, CycC cKO) in cardiomyocytes. The knockout and transgenic mice exhibited decreased cardiac function and altered mitochondria morphology. The hearts of knockout mice had enlarged mitochondria with increased length and area, whereas mitochondria from the hearts of transgenic mice were significantly smaller, demonstrating a role for cyclin C in regulating mitochondrial dynamics in vivo. Hearts from knockout mice displayed altered gene transcription and metabolic function, suggesting that cyclin C is essential for maintaining normal cardiac function. In vitro and in vivo studies revealed that cyclin C translocates to the cytoplasm, enhancing mitochondria fission following stress. We demonstrated that cyclin C interacts with Cdk1 (cyclin‐dependent kinase 1) in vivo following ischemia/reperfusion injury and that, consequently, pretreatment with a Cdk1 inhibitor results in reduced mitochondrial fission. This finding suggests a potential therapeutic target to regulate mitochondrial dynamics in response to stress.

Conclusions
Our study revealed that cyclin C acts as a nuclear‐to‐mitochondrial signaling factor that regulates both cardiac hypertrophic gene expression and mitochondrial fission. This finding provides new insights into the regulation of cardiac energy metabolism following acute ischemic injury.
Exploring Associations Between Cardiac Structure and Retinal Vascular Geometry
Authors: Huang Lihua , Aris Izzuddin M. , Teo Louis L. Y. , Wong Tien Yin , Chen Wei‐Qing , Koh Angela S. , Li Ling‐Jun 
Published: April 2020

Background
Retinal arteriolar narrowing and venular widening has been widely suggested to be associated with subclinical changes in cardiac structure. The novel retinal vascular geometric indices might reflect more comprehensive information on microvasculature other than vascular caliber alone. However, the association between suboptimal retinal vascular geometry and cardiac structural alteration has not been studied.

Methods and Results

We recruited 50 participants without cardiovascular disease from the Cardiac Aging Study conducted between 2014 and 2016. We performed transthoracic echocardiography imaging to measure cardiac structure indices such as left ventricular internal diameter end diastole index, left ventricular internal diameter end systole index, left ventricular mass index, and left atrial volume index, and retinal imaging to measure retinal vascular geometric indices including branching angle, curvature tortuosity, and fractal dimension. We applied multiple linear regressions to examine associations between indices of cardiac structure and retinal vascular geometry, adjusting for age, sex, body mass index, mean blood pressure, and comorbidity. The average age of all participants was 62.54 years old and slightly more than half were male (27; 54%). Each unit increase in a set of cardiac structure indices was associated with larger retinal arteriolar branching angle (β and 95%
CI
: for left ventricular internal diameter end systole index, 26.93°; 6.00–47.86; for left ventricular internal diameter end diastole index, 17.86°; 1.61–34.11; for left ventricular mass index, 0.39°; 0.10–0.67; for left atrial volume index, 0.91°; 0.24–1.58).

Conclusions
Adverse retinal arteriolar geometric morphology mirrored suboptimal cardiac structural alteration.
Impact of the Commercial Introduction of Transcatheter Mitral Valve Repair on Mitral Surgical Practice
Authors: Niikura Hiroki , Gössl Mario , Bae Richard , Sun Benjamin , Askew Judah , Harris Kevin , Mudy Karol , Strauss Craig , Stanberry Larissa , Sweeney Andrea , Sorajja Paul 
Published: April 2020

Background
There has been uncertainty regarding the effect of transcatheter mitral valve repair (TMVr) with MitraClip on cardiac surgical practice. Our aim was to examine the impact of the commercial introduction of TMVr to a comprehensive mitral program.

Methods and Results

We evaluated 875 patients (aged 69±14 years; 58% men) who underwent transcatheter or mitral surgical procedures over a 6‐year period at our institution. Main outcomes were changes in surgical procedural volume after TMVr introduction and short‐term mortality for surgical and TMVr procedures. The numbers of patients treated with MitraClip, isolated mitral repair, and any mitral surgery were 249, 292, and 626 patients, respectively. Compared with surgery, patients with MitraClip were older (aged 82±8 versus 64±12 years;
P
<0.001) and had more severe morbidity. Following the introduction of MitraClip, surgical volumes steadily increased to a rate of 10 (95% CI, 3–7) procedures per year for isolated mitral procedures and 17 (95% CI, 13–20) procedures per year for all mitral surgeries. Both MitraClip and surgical volumes increased at the same rate (
P
=0.42). In‐hospital mortality was 3.2% for MitraClip and 2.1% for all mitral surgeries (
P
=0.33). At 30 days, survival free of all mortality (
P
=0.17) and freedom from heart failure rehospitalization (
P
=0.75) were similar for transcatheter and surgical procedures.

Conclusions
The commercial introduction of TMVr may be associated with growth in cardiac surgery, without detracting from other therapies, and favorable clinical outcomes for all treated mitral regurgitation patients. These findings demonstrate the potential benefits of complementary therapies in the treatment of patients with mitral regurgitation.
Metformin Improves Cardiac Metabolism and Function, and Prevents Left Ventricular Hypertrophy in Spontaneously Hypertensive Rats
Authors: Li Jie , Minćzuk Krzysztof , Massey James C. , Howell Nancy L. , Roy R. Jack , Paul Soumen , Patrie James T. , Kramer Christopher M. , Epstein Frederick H. , Carey Robert M. , Taegtmeyer Heinrich , Keller Susanna R. , Kundu Bijoy K. 
Published: April 2020

Background

In spontaneously hypertensive rats (
SHR
) we observed profound myocardial metabolic changes during early hypertension before development of cardiac dysfunction and left ventricular hypertrophy. In this study, we evaluated whether metformin improved myocardial metabolic abnormalities and simultaneously prevented contractile dysfunction and left ventricular hypertrophy in
SHR
.

Methods and Results

SHR
and control Wistar–Kyoto rats were treated with metformin from 2 to 5 months of age, when
SHR
hearts exhibit metabolic abnormalities and develop cardiac dysfunction and left ventricular hypertrophy. We evaluated the effect of metformin on myocardial glucose uptake rates with dynamic 2‐[
18
F] fluoro‐2‐deoxy‐D‐glucose positron emission tomography. We used cardiac
MRI
in vivo to assess the effect of metformin on ejection fraction, left ventricular mass, and end‐diastolic wall thickness, and also analyzed metabolites,
AMP
‐activated protein kinase and mammalian target‐of‐rapamycin activities, and mean arterial blood pressure. Metformin‐treated
SHR
had lower mean arterial blood pressure but remained hypertensive. Cardiac glucose uptake rates, left ventricular mass/tibia length, wall thickness, and circulating free fatty acid levels decreased to normal, and ejection fraction improved in treated
SHR
. Hearts of treated
SHR
exhibited increased
AMP
‐activated protein kinase phosphorylation and reduced mammalian target‐of‐rapamycin activity. Cardiac metabolite profiling demonstrated that metformin decreased fatty acyl carnitines and markers of oxidative stress in
SHR
.

Conclusions

Metformin reduced blood pressure, normalized myocardial glucose uptake, prevented left ventricular hypertrophy, and improved cardiac function in
SHR
. Metformin may exert its effects by normalizing myocardial
AMPK
and mammalian target‐of‐rapamycin activities, improving fatty acid oxidation, and reducing oxidative stress. Thus, metformin may be a new treatment to prevent or ameliorate chronic hypertension–induced left ventricular hypertrophy.
“All Necessary and Reasonable Measures” – The Bemba Case and the Threshold for Command Responsibility
Authors: Bradley Martha M. , de Beer Aniel 
Published: April 2020

On 21 March 2016 Trial Chamber iii of the International Criminal Court unanimously convicted the former Vice-President of the Democratic Republic of the Congo, Jean-Pierre Bemba Gombo, on the basis of the doctrine of command responsibility for crimes against humanity and war crimes committed by troops under his command in the Central African Republic from 2002 to 2003. On 8 June 2018 however, the Appeals Chamber reversed the judgment and acquitted Bemba of all charges. The Appeals Chamber held that the Trial Chamber erred in finding that Bemba failed to take all necessary and reasonable measures to prevent and repress crimes committed by his subordinates as contemplated in Article 28(a)(ii) of the Rome Statute. This article evaluates the meaning of “all necessary and reasonable measures” in the context of command responsibility and considers whether Bemba met this threshold in order to avoid incurring criminal responsibility under Article 28(a)(ii).
Religious Pluralism and Its Impacts on the Configuration of Secularism in Brazil
Authors: Montero Paula 
Published: April 2020

Abstract
Using Davis Buckley’s (2013) notion of “Benevolent Secularism” this article examines how the evangelical movement in Brazil, in particular, the neopentecostal movement, challenges the historical stability of relations between state and religion. Until very recently this relationship was based on cooperation between the Catholic Church and the State in the one hand and an inter-religious coalition led by Catholicism in the other. In this text, I will first discuss the concept of “benevolent secularism” and its theoretical-methodological implications. Then, I will present empiric examples to describe how Christian religions relate to politics in Brazil. Those examples will test the applicability of Buckley’s concept to represent Brazilian secularism. And, they will also demonstrate the heuristic virtues of this concept for the understanding of the impact of the evangelical modus operandi in the configuration of the secular in Brazilian society.