Mitochondria play a crucial role in cellular energy production, signaling and homeostasis. Respiratory supercomplexes represent evolutionary well-conserved, stable associations between membrane complexes and molecules...
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Mitochondria play a crucial role in cellular energy production, signaling and homeostasis. Respiratory supercomplexes represent evolutionary well-conserved, stable associations between membrane complexes and molecules, including proteins and lipids, within the inner mitochondrial membrane. They dynamically respond to metabolic demands and enhance the electron transfer rate, thereby reducing the production of ROS. Recent research has unveiled cytochrome c , a mobile electron carrier between complexes III and IV, as a potential key player in orchestrating the formation of these supra-associations. This study centers on elucidating the role of cytochrome c in modulating the assembly of supercomplexes, using the Saccharomyces cerevisiae yeast as a model system for mitochondrial metabolism. BN-PAGE and mass spectrometry-based proteomic analysis were employed to examine supercomplex organization in yeast strains expressing different cytochrome c isoforms, grown under fermentative and respiratory conditions. Our results demonstrate that both isoforms of cytochrome ccontribute to supercomplex assembly, with isoform-2 significantly improving electron transfer and lowering ROS levels. We propose a model in which cytochrome c acts as a scaffold for the recruitment of assembly factors, facilitating the formation of higher order supercomplexes such as III 2 IV 2 . This model highlights cytochrome c 's role beyond electron transfer, as it regulates supercomplex assembly and mitochondrial homeostasis.
This paper deals with multiobjective programming problems with support functions under(G, c, ρ)-convexity assumptions. Not only sufficient but also necessary optimality conditions for this kind of multiobjective prog...
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This paper deals with multiobjective programming problems with support functions under(G, c, ρ)-convexity assumptions. Not only sufficient but also necessary optimality conditions for this kind of multiobjective programming problems are established from a viewpoint of(G, c, ρ)-*** the sufficient conditions are utilized, the corresponding duality theorems are derived for general Mond-Weir type dual program.
In this work, the life prediction of c/Siccomposites subjected to stochastic load spectra with hold cycles is investigated using a damage-based micromechanical model. Relationships between the fiber's architectur...
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In this work, the life prediction of c/Siccomposites subjected to stochastic load spectra with hold cycles is investigated using a damage-based micromechanical model. Relationships between the fiber's architecture (i.e., 1D unidirectional, 2D crossply and plain-woven, 2.5D woven, and 3D braided), stochastic load spectra, hold cycles, fiber-fragmentation probability (FFP), and composite fatigue-life degradation rate (FFDR) are established. Experimental FFDR and FFP in different c/Siccomposites are predicted. Under the low fatigue peak stress, the FFDR is the highest during increasing stochastic stress for 1D and 3D c/Sic and is the highest during decreasing stochastic stress for 2D and 2.5D c/Sic. Under the high fatigue peak stress, the FFDR is the highest during decreasing stochastic stress for 1D, 2D, 2.5D and 3D c/Sic. The FFDR at the constant stochastic stress level is the lowest under the low or high fatigue peak stress.
A set of general routines for three-dimensional computer graphics, including removal of hidden lines and surfaces, shading, and antialiasing, are described. Problems encountered in their implementation are discussed. ...
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A set of general routines for three-dimensional computer graphics, including removal of hidden lines and surfaces, shading, and antialiasing, are described. Problems encountered in their implementation are discussed. The routines are written in c, display arbitrarily complex objects, and are optimized to produce high-quality images on personal computers of the IBM Pc, AT, and PS/2 families equipped with VGA graphic interfaces. A few applications of these techniques to the geosciences are suggested.
The c Programming Language is known for being an efficient language that can be compiled on almost any architecture and operating system. However the absence of dynamic safety checks and a relatively weak type system ...
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The c Programming Language is known for being an efficient language that can be compiled on almost any architecture and operating system. However the absence of dynamic safety checks and a relatively weak type system allows programmer oversights that are hard to spot. In this paper, we present RTc, a runtime monitoring tool that instruments unsafe code and monitors the program execution. RTc is built on top of the ROSE compiler infrastructure. RTc finds memory bugs and arithmetic overflows and underfiows, and run-time type violations. Most of the instrumentations are directly added to the source file and only require a minimal runtime system. As a result, the instrumented code remains portable. In tests against known error detection benchmarks, RTc found 98% of all memory related bugs and had zero false positives. In performance tests conducted with well known algorithms, such as binary search and MD5, we determined that our tool has an average run-time overhead rate of 9.7 x and memory overhead rate of 3.5 x. (c) 2016 Elsevier Ltd. All rights reserved.
c++ [1, 2] extends a modern, general purpose programming language into the object-oriented programming paradigm. The language ameliorates disadvatanges of c while introducing new problems. Advantages and disadvantages...
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c++ [1, 2] extends a modern, general purpose programming language into the object-oriented programming paradigm. The language ameliorates disadvatanges of c while introducing new problems. Advantages and disadvantages of traditional c [3, 4] have been discussed in [5]. This paper assesses c++, examining why it is better general purpose programming langauge. Since c++ is “object-oriented” we consider how well it implements that metaphor. In this paper we assume the reader has a working knowledge of the c programming language. Section 1 briefly enumerates advantages and disadvantages of c to provide a context for assessing c++. In Section 2 we describe new c++ features and discuss ways they ameliorate shortcomings of c. Section 3 describes philosophical and practical problems with c++. The last section assesses c++ as a successor to c.
Systems code is almost universally written in the c programming language or a variant. c has a very low level of type and memory abstraction and formal reasoning about c systems code requires a memory model that is ab...
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Systems code is almost universally written in the c programming language or a variant. c has a very low level of type and memory abstraction and formal reasoning about c systems code requires a memory model that is able to capture the semantics of c pointers and types. At the same time, proof-based verification demands abstraction, in particular from the aliasing and frame problems. In this paper we present a study in the mechanisation of two proof abstractions for pointer program verification in the Isabelle/HOL theorem prover, based on a low-level memory model for c. The language's type system presents challenges for the multiple independent typed heaps (Burstall-Bornat) and separation logic proof techniques. In addition to issues arising from explicit value size/alignment, padding, type-unsafe casts and pointer address arithmetic, structured types such as c's arrays and structs are problematic due to the non-monotonic nature of pointer and lvalue validity in the presence of the unary &-operator. For example, type-safe updates through pointers to fields of a struct break the independence of updates across typed heaps or a (*)-conjuncts. We provide models and rules that are able to cope with these language features and types, eschewing common over-simplifications and utilising expressive shallow embeddings in higher-order logic. Two case studies are provided that demonstrate the applicability of the mechanised models to real-world systems code;a working of the standard in-place list reversal example and an overview of the verification of the L4 microkernel's memory allocator.
OpencL is an open standard for parallel programming of heterogeneous compute devices, such as GPUs, cPUs, DSPs or FPGAs. However, the verbosity of its c host API can hinder application development. In this paper we pr...
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OpencL is an open standard for parallel programming of heterogeneous compute devices, such as GPUs, cPUs, DSPs or FPGAs. However, the verbosity of its c host API can hinder application development. In this paper we present cf4ocl, a software library for rapid development of OpencL programs in pure c. It aims to reduce the verbosity of the OpencL API, offering straightforward memory management, integrated profiling of events (e.g., kernel execution and data transfers), simple but extensible device selection mechanism and user-friendly error management. We compare two versions of a conceptual application example, one based on cf4ocl, the other developed directly with the OpencL host API. Results show that the former is simpler to implement and offers more features, at the cost of an effectively negligible computational overhead. Additionally, the tools provided with cf4ocl allowed for a quick analysis on how to optimize the application. (c) 2017 Elsevier B.V. All rights reserved.
We address the problem of estimating the carrier-to-noise ratio (c/N-0) in weak signal conditions. There are several environments, such as forested areas, indoor buildings and urban canyons, where high-sensitivity glo...
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We address the problem of estimating the carrier-to-noise ratio (c/N-0) in weak signal conditions. There are several environments, such as forested areas, indoor buildings and urban canyons, where high-sensitivity global navigation satellite system (HS-GNSS) receivers are expected to work under these reception conditions. The acquisition of weak signals from the satellites requires the use of post-detection integration (PDI) techniques to accumulate enough energy to detect them. However, due to the attenuation suffered by these signals, estimating their c/N-0 becomes a challenge. Measurements of c/N-0 are important in many applications of HS-GNSS receivers such as the determination of a detection threshold or the mitigation of near-far problems. For this reason, different techniques have been proposed in the literature to estimate the c/N-0, but they only work properly in the high c/N-0 region where the coherent integration is enough to acquire the satellites. We derive four c/N-0 estimators that are specially designed for HS-GNSS snapshot receivers and only use the output of a PDI technique to perform the estimation. We consider four PDI techniques, namely non-coherent PDI, non-quadratic non-coherent PDI, differential PDI and truncated generalized PDI and we obtain the corresponding c/N-0 estimator for each of them. Our performance analysis shows a significant advantage of the proposed estimators with respect to other c/N-0 estimators available in the literature in terms of estimation accuracy and computational resources.
A significant correlation between the in-plane (IP) and out-of-plane (OOP) damage propagation of masonry infills (MIs) is frequently observed after strong earthquakes, posing a serious problem as regards vulnerability...
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A significant correlation between the in-plane (IP) and out-of-plane (OOP) damage propagation of masonry infills (MIs) is frequently observed after strong earthquakes, posing a serious problem as regards vulnerability of public buildings such as schools. The present work is aimed at identifying the effects of different IP and OOP modelling assumptions of MIs on their seismic damage. To this end, the state secondary school De Gasperi-Battaglia in Norcia (Italy), object of monitoring by the Department of civil Protection since 2000, is investigated for the heterogeneity of infill typologies. The school is composed of a basement and three storeys above ground level, with a reinforced concrete (r.c.) framed structure having a long-shaped rectangular plan. Two typologies can be identified in terms of transverse layout of MIs: (i) double-leaf interior partitions, made of hollow clay bricks;(ii) double-leaf exterior infill walls, constituted by facade solid bricks paired with hollow clay bricks. In addition, partial height infills in the longitudinal direction, due to classroom windows, make the columns susceptible to short column effects. MIs are represented by a five-element macro-model predicting both in-plane (IP) and out-of-plane (OOP) behaviour through a horizontal nonlinear truss and four diagonal nonlinear beam elements, respectively. Stiffness and strength values in the OOP direction are also reduced considering the evolution of the IP damage. Three assumptions are investigated for the behaviour of structural MIs: i.e. elastic both IP and OOP;inelastic IP and elastic OOP;inelastic both IP and OOP. Bare and infilled test structures are subjected to biaxial spectrum-compatible accelerograms, to evaluate the IP and OOP damage levels and effectiveness of the OOP simplified verification proposed by seismiccodes.
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