Miracle-dz/UniFAR-FTUs huggingface dataset:
Exponential Recency Weighted Average Branching Heuristic for SAT Solvers

Modern conflict-driven clause-learning SAT solvers routinely solve large real-world instances with millions of clauses and variables in them. Their success crucially depends on effective branching heuristics. In this paper, we propose a new branching heuristic inspired by the exponential recency weighted average algorithm used to solve the bandit problem. The branching heuristic, we call CHB, learns online which variables to branch on by leveraging the feedback received from conflict analysis. We evaluated CHB on 1200 instances from the SAT Competition 2013 and 2014 instances, and showed that CHB solves significantly more instances than VSIDS, currently the most effective branching heuristic in widespread use. More precisely, we implemented CHB as part of the MiniSat and Glucose solvers, and performed an apple-to-apple comparison with their VSIDS-based variants. CHB-based MiniSat (resp. CHB-based Glucose) solved approximately 16.1% (resp. 5.6%) more instances than their VSIDS-based variants. Additionally, CHB-based solvers are much more efficient at constructing first preimage attacks on step-reduced SHA-1 and MD5 cryptographic hash functions, than their VSIDS-based counterparts. To the best of our knowledge, CHB is the first branching heuristic to solve significantly more instances than VSIDS on a large, diverse benchmark of real-world instances.
A safe multiple access-rates transmission (SMART) scheme for IEEE 802.11 wireless networks

The IEEE 802.11 standard and enhanced amendments have defined fourteen transmission rates (1/2/5.5/6/9/11/12/18/22/24/33/36/48/54 Mbit/s) for mobile stations to transmit and receive data frames. With the characteristic of modulation schemes, a higher level modulation scheme requires a higher signal-to-noise ratio (SNR) and, consequently, the data rate is inversely proportional with the transmission distance. Using a higher level modulation scheme, a higher network throughput can be expected; however, the frame error probability will also become higher. Doubtlessly, it is an open issue of selecting a proper modulation scheme for a pair of mobile stations in a time-varying indoor environment. This paper proposes a safe multiple access-rates transmission (SMART) scheme for enhancing the reliability of data transmission in the IEEE 802.11 multi-rate infrastructure wireless networks. The SMART scheme provides reliable transmission by reserving a retransmission period, which immediately follows the transmitted frame and is estimated from a lower transmission rate, for each transmitted frame. If any error occurs on the transmitted frame, the sender will retransmit it right away by using a lower transmission rate to make sure of successful retransmission. Otherwise, the reserved period will be taken by the access point (AP), which often has the longest waiting queue and is the bottleneck in infrastructure wireless networks. The efficiency of the proposed SMART scheme is evaluated by simulation. Simulation results show that the derived performance of the SMART scheme is significantly better than standard under the real environment with asymmetric traffic load.
Evolution of the Chaperone/Usher Assembly Pathway: Fimbrial Classification Goes Greek

SUMMARY Many Proteobacteria use the chaperone/usher pathway to assemble proteinaceous filaments on the bacterial surface. These filaments can curl into fimbrial or nonfimbrial surface structures (e.g., a capsule or spore coat). This article reviews the phylogeny of operons belonging to the chaperone/usher assembly class to explore the utility of establishing a scheme for subdividing them into clades of phylogenetically related gene clusters. Based on usher amino acid sequence comparisons, our analysis shows that the chaperone/usher assembly class is subdivided into six major phylogenetic clades, which we have termed α-, β-, γ-, κ-, π-, and σ-fimbriae. Members of each clade share related operon structures and encode fimbrial subunits with similar protein domains. The proposed classification system offers a simple and convenient method for assigning newly discovered chaperone/usher systems to one of the six major phylogenetic groups.
Verifying event-driven programs using ramified frame properties

Interactive programs, such as GUIs or spreadsheets, often maintain dependency information over dynamically-created networks of objects. That is, each imperative object tracks not only the objects its own invariant depends on, but also all of the objects which depend upon it, in order to notify them when it changes. These bidirectional linkages pose a serious challenge to verification, because their correctness relies upon a global invariant over the object graph. We show how to modularly verify programs written using dynamically-generated bidirectional dependency information. The critical idea is to distinguish between the footprint of a command, and the state whose invariants depends upon the footprint. To do so, we define an application-specific semantics of updates, and introduce the concept of a ramification operator to explain how local changes can alter our knowledge of the rest of the heap. We illustrate the applicability of this style of proof with a case study from functional reactive programming, and formally justify reasoning about an extremely imperative implementation as if it were pure.
Acute vagal stimulation attenuates cardiac metabolic response to β‐adrenergic stress

• Whereas the effects of catecholamines on myocardial metabolism are well characterized, the potential role of the parasympathetic system is generally considered minor or absent. • We tested the hypothesis that acute stimulation of the right vagus nerve alters the balance between cardiac free fatty acid and carbohydrate oxidation and opposes the metabolic effects of beta‐adrenergic stimulation. • Using a clinical‐type selective stimulator of the vagal efferent fibers in dogs, we found that vagal stimulation did not significantly affect baseline cardiac performance, haemodynamics and myocardial metabolism. • During dobutamine stress, vagal stimulation attenuated the increase in left ventricular mechanical performance, cardiac oxygen consumption and myocardial glucose oxidation, while free fatty acid oxidation was affected only at low catecholamine dose. • Our results elucidate a previously unexplored parasympathetic function, indicating that selective vagal efferent stimulation antagonizes the effects of beta‐adrenergic activation on myocardial metabolism.
Drug delivery from engineered organisms and nanocarriers as monitored by multimodal imaging technologies

In recent years, while the research budget and development times increased for different phases of drug development, the number of clinically approved new medicines declined. In fact, many promising drug candidates failed to demonstrate their full therapeutic potential in vivo. Reasons for unfavorable outcome include some intrinsic properties of drugs, like biodegradation, solubility, and systemic toxicity, as well as the ways in which they are administered or the time elapsed until therapeutic efficiency is demonstrated. Therefore, to develop the full therapeutic potential of drug candidates in vivo, there is a need for advanced drug delivery systems that would carry the drug specifically to the target and release it there at desired concentrations. In addition, there is a requirement for non-invasive biomedical imaging technologies allowing for rapid and sensitive evaluations of drug performance in vivo. This review will present recent developments in bioengineered drug delivery systems, highlighting the biomedical imaging tools needed to evaluate the success of drug delivery strategies.
Targeting AGGF1 (angiogenic factor with G patch and FHA domains 1) for Blocking Neointimal Formation After Vascular Injury

Background Despite recent improvements in angioplasty and placement of drug‐eluting stents in treatment of atherosclerosis, restenosis and in‐stent thrombosis impede treatment efficacy and cause numerous deaths. Research efforts are needed to identify new molecular targets for blocking restenosis. We aim to establish angiogenic factor AGGF1 (angiogenic factor with G patch and FHA domains 1) as a novel target for blocking neointimal formation and restenosis after vascular injury. Methods and Results AGGF1 shows strong expression in carotid arteries; however, its expression is markedly decreased in arteries after vascular injury. AGGF1+/− mice show increased neointimal formation accompanied with increased proliferation of vascular smooth muscle cells (VSMCs) in carotid arteries after vascular injury. Importantly, AGGF1 protein therapy blocks neointimal formation after vascular injury by inhibiting the proliferation and promoting phenotypic switching of VSMCs to the contractile phenotype in mice in vivo. In vitro, AGGF1 significantly inhibits VSMCs proliferation and decreases the cell numbers at the S phase. AGGF1 also blocks platelet‐derived growth factor‐BB–induced proliferation, migration of VSMCs, increases expression of cyclin D, and decreases expression of p21 and p27. AGGF1 inhibits phenotypic switching of VSMCs to the synthetic phenotype by countering the inhibitory effect of platelet‐derived growth factor‐BB on SRF expression and the formation of the myocardin/SRF/CArG‐box complex involved in activation of VSMCs markers. Finally, we show that AGGF1 inhibits platelet‐derived growth factor‐BB–induced phosphorylation of MEK1/2, ERK1/2, and Elk phosphorylation involved in the phenotypic switching of VSMCs, and that overexpression of Elk abolishes the effect of AGGF1. Conclusions AGGF1 protein therapy is effective in blocking neointimal formation after vascular injury by regulating a novel AGGF1‐MEK1/2‐ERK1/2‐Elk‐myocardin‐SRF/p27 signaling pathway.
In Search of Better Spermatogonial Preservation by Supplementation of Cryopreserved Human Immature Testicular Tissue Xenografts with N-acetylcysteine and Testosterone

Controlled slow-freezing is the procedure currently applied for immature testicular tissue (ITT) cryobanking in clinical practice. Vitrification has been proposed as a promising alternative, with a view to better preserve the spermatogonial stem cells for future fertility restoration by autografting in young boys suffering from cancer. It appears that besides the potential influence of the cryopreservation technique used, the transplantation procedure itself has a significant impact on spermatogonial loss observed in ITT xenografts. Eighteen ITT pieces issued from 6 patients aged 2–15 years were used. Fragments of fresh tissue (serving as ungrafted controls), frozen-thawed tissue, frozen-thawed tissue supplemented with N-acetylcysteine (NAC), and frozen-thawed tissue supplemented with testosterone xenografted to nude mice for 5 days were compared. Upon graft removal, histological and immunohistochemical analyses were performed to evaluate spermatogonia, intratubular proliferation, and intrinsic and extrinsic apoptosis. A significant decrease in the integrity of intact seminiferous tubules was found in all three grafted groups. Spermatogonia were observed by immunohistochemistry in all grafted groups, with recovery rates of 67, 63, and 53%, respectively, for slow-frozen tissue, slow-frozen tissue supplemented with NAC, and slow-frozen tissue supplemented with testosterone. Apoptosis evidenced by active caspase-3 and terminal deoxynucleotidyl transferase-mediated dUTP nick end labeling was similar in all grafts. The study is limited by the low availability of ITT samples of human origin, and no clear impact of graft supplementation was found. The mouse xenotransplantation model needs to be refined to investigate human spermatogenesis in human ITT grafts.
Endoplasmic reticulum—shape and function in stress translation

The endoplasmic reticulum (ER) is a very versatile organelle. Besides its major role as the gateway to the secretory pathway the ER is central to adaptation against abiotic and biotic stress. Here, we summarize the current knowledge on ER dynamics and architecture, the association and interaction of the ER with other organelles as well as its role in stress translation and adaptation (Figure 1).
The Flask Security Architecture: System Support for Diverse Security Policies

Operating systems must be flexible in their support for security policies, providing sufficient mechanisms for supporting the wide variety of real-world security policies. Such flexibility requires controlling the propagation of access rights, enforcing fine-grained access rights and supporting the revocation of previously granted access rights. Previous systems are lacking in at least one of these areas. In this paper we present an operating system security architecture that solves these problems. Control over propagation is provided by ensuring that the security policy is consulted for every security decision. This control is achieved without significant performance degradation through the use of a security decision caching mechanism that ensures a consistent view of policy decisions. Both fine-grained access rights and revocation support are provided by mechanisms that are directly integrated into the service-providing components of the system. The architecture is described through its prototype implementation in the Flask microkernel-based operating system, and the policy flexibility of the prototype is evaluated. We present initial evidence that the architecture's impact on both performance and code complexity is modest. Moreover, our architecture is applicable to many other types of operating systems and environments.
TR-2011-016 A Bayesian approach to data assimilation for the incompressible Navier-Stokes equations with applications to hemodynamics

The reliable and effective assimilation of measurements and numerical simulations in engineering applications involving computational fluid dynamics is an emerging problem as soon as new devices provide more data. In this paper we are mainly driven by hemodynamics applications, a field where the progressive increment of measures and numerical tools makes this problem particularly upto-date. We adopt a Bayesian approach to the inclusion of noisy data in the incompressible steady Navier-Stokes equations (NSE). The purpose is the estimation of statistical features of velocity and flow related variables of interest, all treated as random variables. The method consists in the solution of an optimization problem where a weighted misfit between data and velocity is minimized under the constraint of the NSE. We derive point estimators (the maximum a posteriori MAP and the maximum likelihood ML estimators) and confidence regions for velocity and wall shear stress, a flow related variable of medical relevance. Numerical simulations in 2-dimensional and axisymmetric 3-dimensional domains show the gain in using statistical estimators versus deterministic ones. 1991 Mathematics Subject Classification. 76D06,76M10,62F15,60H30. The dates will be set by the publisher.
Mechanical behavior of flexible silicon devices curved in spherical configurations

Foldable, stretchable and flexible electronics is of constant increasing interest since the early 2000's. Its applications spread from OLED-based displays, bio-inspired detectors and “epidermal electronics”. Cylindrical curvature is largely studied through many 3 points and 4 points bending variations in electronic devices. However spherical curvature is poorly addressed, especially for monolithic approach. In this paper, a simulation and experiments of the elastic deformation of a thin silicon chip on a spherical holder are presented. The holder can have a concave or a convex shape. The chip is a square of 10 by 10 mm2. Its thickness is 50, 25 or 15 μm. The simulation is performed in 3 steps. First, the use of a shell model is validated by a convergence study and by a comparison with a 3D model and the literature. Then, the influence of the anisotropic elastic behavior (single crystal) is considered. In a given bulge test condition, isotropic and anisotropic silicon simulation gave similar deformations. At the end, the spherical forming is accomplished with a shell model and an anisotropic law. Experimental data is obtained by curving thin silicon plates of various thicknesses on different radii holders in a press. The comparison between experimental and computed results is realized. We found similar macroscopic deformations for both concave and convex shapes. The influence of chip thickness and applied pressure is studied on characteristic folds and flat part amplitudes. A heterogeneous stress distribution with hundreds of MPa variations can explain the difference observed between curved chips and perfect spherical holders. The stress level in electrical and optical active layers of thin curved silicon-based devices may affect their properties. A numerical example on a bolometer gives a stress-induced resistivity variation over 10%.
Micaceous mainwall insulation for high-voltage rotating machines

The mineral mica has found application in the mainwall insulation of high-voltage electric rotating machines for over a century, and remains intrinsic to achieving high machine reliability and lifetimes. This paper retraces the historical development of micaceous mainwall insulation, and examines the materials and construction of modern mica tapes in detail. In this context, we provide examples of the multitude of available mica tapes, and review various properties of mica tapes relevant to their manufacture, application, and performance, concluding with some observed trends.
Signal Processing Algorithm of Space Time Coded Waveforms for Coherent MIMO Radar: Overview on Target Localization

: Space-time coding (STC) has been shown to play a key role in the design of MIMO radars with closely spaced antennas. Multiple-input–multiple-output (MIMO) radar is emerging technology for target detection, parameter identification, and target classification due to diversity of waveform and perspective. First, it turns out that a joint waveform optimization problem can be decoupled into a set of individual waveform design problems. Second, a number of mono-static waveforms can be directly used in a MIMO radar system, which offers flexibility in waveform selection. We provide conditions for the elimination of waveform cross correlation. However, the mutual interference among the waveforms may lead to performance degradation in resolving spatially close returns. We consider the use of space–time coding (STC) to mitigate the waveform cross-correlation effects in MIMO radar. In addition, we also extend the model to partial waveform cross-correlation removal based on waveform set division. Numerical results demonstrate the effectiveness of STC in MIMO radar for waveform de-correlation. This paper introduces the signal processing issued for the coherent MIMO radar without and with STC waveforms and also studied signal processing algorithms of coherent MIMO radar with STC waveforms for improvement of target detection and recognition performance for real life scenario.
Facilitating the Practical Evaluation of Organizational Memories Using the Goal-Question-Metric Technique

It is an important industrial need to deliver high-quality knowledge-based systems and organizational memories (e.g., to support service management or knowledge management in general). Evaluation is required to ensure this high quality and guide the development and maintenance. We present an approach for facilitating practical evaluation of organizational memories that meets the requirements for good measurements in knowledge engineering. The base of this methodology is the GoalQuestion-Metric (GQM) technique, which is an industrial-strength technique for goaloriented measurement and evaluation from the field of software engineering. The practical benefit of GQM is demonstrated by a case study where GQM was applied to an existing case-based reasoning system/application.
Ideal Midline Detection Using Automated Processing of Brain CT Image

Brain ideal midline estimation is vital in medical image processing, especially in analyzing the severity of a brain injury in clinical environments. We propose an automated computer-aided ideal midline estimation system with a two-step process. First, a CT Slice Selection Algorithm (SSA) can automatically select an appropriate subset of slices from a large number of raw CT images using the skull’s anatomical features. Next, an ideal midline detection is implemented on the selected subset of slices. An exhaustive symmetric position search is performed based on the anatomical features in the detection. In order to enhance the accuracy of the detection, a global rotation assumption is applied to determine the ideal midline by fully considering the connection between slices. Experimental results of the multi-stage algorithm were assessed on 3313 CT slices of 70 patients. The accuracy of the proposed system is 96.9%, which makes it viable for use under clinical settings.
Nature of printer-generated ultrafine particles and their formation processes

Laser printers are a significant source of ultrafine particles (< 100 nm) in the indoor environment (He et al. 2007). These particles are of a secondary nature and may pose risks to human health (Ewers and Nowak, 2006). A number of materials and mechanisms may participate to the formation of these particles (Morawska et al. 2009). However, whilst the mixing state of these generated particles can help to indirectly validate the proposed particle formation mechanisms, no studies have been conducted to investigate this to date. This study aimed to improve the understanding of ultrafine particle formation processes according the mixing state of printer-generated particles, by examining their volatility and hygroscopicity.
Clonal analysis of isolated intestinal metaplastic glands of stomach using X linked polymorphism

Background—Monoclonal precancerous cells undergo successive biochemical and genetic changes during the multistep process of carcinogenesis in the gastrointestinal tract. Despite a high association with intestinal-type stomach cancer (differentiated adenocarcinoma of the stomach), the role of intestinal metaplasia is unclear in stomach carcinogenesis. Aims—To study the clonality of intestinal metaplasia. Methods—The clonality of 86 single intestinal metaplastic glands isolated by EDTA treatment from gastrectomy specimens from patients with cancer were investigated. The methylation sensitive restriction enzyme HpaII and polymerase chain reaction (PCR) were used to detect a polymorphic human androgen receptor gene locus linked to an inactive X chromosome. Results—Forty one (48%) intestinal metaplastic glands were heterotypic (mixed cells of different allelic methylation) and 45 (52%) were homotypic (cell population of the same allelic methylation), while almost all the single pyloric glands were homotypic. Eleven of 13 intestinal metaplastic mucosae that were 6 mm in diameter contained glands that had originated from different cells. There were no strong relationships between clonal type and location or histological type of intestinal metaplasia. Conclusion—Intestinal metaplasia in general is not a lesion that arises or proceeds monoclonally.