Academic literature on the topic 'MAC hash function'
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Journal articles on the topic "MAC hash function"
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Konorski, Jerzy, and Maciej Kurant. "Application of a hash function to discourage MAC-layer misbehaviour in wireless LANs." Journal of Telecommunications and Information Technology, no. 2 (June 30, 2004): 38–46. http://dx.doi.org/10.26636/jtit.2004.2.242.
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Contention-based MAC protocols for wireless ad hoc LANs rely on random deferment of packet transmissions to avoid collisions. By selfishly modifying the probabilities of deferments greedy stations can grab more bandwidth than regular stations that apply standard-prescribed probabilities. To discourage such misbehaviour we propose a protocol called RT-hash whereby the winner of a contention is determined using a public hash function of the channel feedback. RT-hash is effective in a full hearability topology, assuming that improper timing of control frames is detectable and that greedy stations do not resort to malicious actions. Simulation experiments show that RT-hash protects regular stations` bandwidth share against various sophisticated greedy strategies of deferment selection; as such it may contribute to MAC-layer network security.
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Muraharirao, Siva Charan, and Manik Lal Das. "Digital Image Protection using Keyed Hash Function." International Journal of Computer Vision and Image Processing 2, no. 2 (2012): 36–47. http://dx.doi.org/10.4018/ijcvip.2012040103.
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Digital image authentication is an essential attribute for protecting digital image from piracy and copyright violator. Anti-piracy, digital watermarking, and ownership verification are some mechanisms evolving over the years for achieving digital image authentication. Cryptographic primitives, such as hash function, digital signature, and message authentication codes are being used in several applications including digital image authentication. Use of Least Significant Bit (LSB) is one of the classical approaches for digital image authentication. Although LSB approach is efficient, it does not provide adequate security services. On the other hand, digital signature-based image authentication provides better security, but with added computational cost in comparison with LSB approach. Furthermore, digital signature-based authentication approach requires managing public key infrastructure. Considering security weakness of LSB-based approach and cost overhead of public key based approach, the authors present a digital image authentication scheme using LSB and message authentication codes (MAC). The MAC-based approach for authenticating digital image is secure and efficient approach without public key management overhead. The authors also provide experimental results of the proposed scheme using MATLAB. The experimental results show that the proposed scheme is efficient and secure in comparisons with other schemes.
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Rechberger, Christian, and Vincent Rijmen. "New Results on NMAC/HMAC when Instantiated with Popular Hash Functions." JUCS - Journal of Universal Computer Science 14, no. (3) (2008): 347–76. https://doi.org/10.3217/jucs-014-03-0347.
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Message Authentication Code (MAC) algorithms can provide cryptographically secure authentication services. One of the most popular algorithms in commercial applications is HMAC based on the hash functions MD5 or SHA-1. In the light of new collision search methods for members of the MD4 family including SHA-1, the security of HMAC based on these hash functions is reconsidered. We present a new method to recover both the inner- and the outer key used in HMAC when instantiated with a concrete hash function by observing text/MAC pairs. In addition to collisions, also other non-random properties of the hash function are used in this new attack. Among the examples of the proposed method, the first theoretical full key recovery attack on NMAC-MD5 is presented. Other examples are distinguishing, forgery and partial or full key recovery attacks on NMAC/HMAC-SHA-1 with a reduced number of steps (up to 62 out of 80). This information about the new, reduced security margin serves as an input to the selection of algorithms for authentication purposes.
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Ichwan, M., Milda Gustian, and Novan Rizky Nurjaman. "Implementasi Keyed-Hash Message Authentatication Code Pada Sistem Keamanan Rumah." MIND Journal 1, no. 1 (2018): 9. http://dx.doi.org/10.26760/mindjournal.v1i1.9.
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Keyed-Hash Message Authentication Code (HMAC) adalah algoritma untuk menghitung nilai MAC (Message Authentication Code) yang menggunakan Fungsi Hash dikombinasikan dengan sebuah kunci rahasia, Fungsi Hash yang digunakan dalam penelitian ini adalah Secure Ha sh Algorithm 256 (SHA256). Nilai MAC digunakan sebagai otentikasi untuk menjamin integritas data dan keaslian pesan. Algoritma ini di implementasikan pada sistem keamanan rumah, dimana pertukaran pesan antara user dan sistem keamanan di otentikasi dengan menggunakan HMAC. Keamanan algoritma HMAC ini dibuktikan dengan hasil pengujian Avalanche effect yang mencapai 87.5% pada fungsi Hash yang digunakan ,dan dibutuhkan waktu sampai 84 tahun untuk serangan Brute force berhasil pada kunci dengan panjang 8 karakter. Kata kunci: keyed-Hash Message Authentication Code, Hash function, Avalanche effect, Brute force attack
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Kiryukhin, Vitaly A., and Andrey M. Sergeev. "“Sandwich”-like keyed algorithm based on the “Streebog” hash function." Prikladnaya Diskretnaya Matematika, no. 63 (2024): 24–48. http://dx.doi.org/10.17223/20710410/63/2.
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We propose a keyed cryptographic algorithm based on the “Streebog” hash function. We do not make any structural changes to the hash function itself, but only introduce a special type of padding. As a result, the key appears on both sides of the message in so-called “sandwich” manner - hence the name Streebog-S for our construction. “Sandwich” properties make it possible to simplify defenses against side-channel attacks while maintaining their effectiveness. We prove that Streebog-S and other algorithms based on “Streebog”, HMAC-Streebog and Streebog-K, remain secure as pseudorandom functions (PRF) and message authentication codes (MAC) even when almost all internal states are leaked to the adversary. This leakage resistance requires additional properties from the underlying compression function, namely collision- and preimage-resistance.
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Rogi, Yuki, Manami Hagizaki, Tatsuya Oyama, et al. "Hash-Based Message Authentication Code with a Reverse Fuzzy Extractor for a CMOS Image Sensor." Electronics 14, no. 10 (2025): 1971. https://doi.org/10.3390/electronics14101971.
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The MIPI (Mobile Industry Processor Interface) Alliance provides a security framework for in-vehicle network connections between sensors and processing electronic control units (ECUs). One approach within this framework is data integrity verification for sensors with limited hardware resources. In this paper, the security risks associated with image sensor data are described. Adversarial examples (AEs) targeting the MIPI interface can induce misclassification, making image data integrity verification essential. A CMOS image sensor with a message authentication code (CIS-MAC) is then proposed as a defense mechanism starting from the image sensor to protect image data from malicious manipulations, such as AE attacks. Evaluation results of the physically unclonable function (PUF) response and random number, which are utilized for generating the cryptographic key and MAC tag, are presented using a 2 Mpixel CMOS image sensor. The area of the CIS-MAC circuit is estimated based on a Verilog HDL design and synthesis using a 0.18 μm CMOS process. Various hash topologies are evaluated to select a hash function suitable for key generation and MAC tag generation within the CMOS image sensor. The estimated area of the CIS-MAC circuit is 67 kGE and 0.86mm2, demonstrating feasibility for implementation in a CMOS image sensor typically fabricated using analog process technology.
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Bariant, Augustin, Jules Baudrin, Gaëtan Leurent, Clara Pernot, Léo Perrin, and Thomas Peyrin. "Fast AES-Based Universal Hash Functions and MACs." IACR Transactions on Symmetric Cryptology 2024, no. 2 (2024): 35–67. http://dx.doi.org/10.46586/tosc.v2024.i2.35-67.
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Ultra-fast AES round-based software cryptographic authentication/encryption primitives have recently seen important developments, fuelled by the authenticated encryption competition CAESAR and the prospect of future high-profile applications such as post-5G telecommunication technology security standards. In particular, Universal Hash Functions (UHF) are crucial primitives used as core components in many popular modes of operation for various use-cases, such as Message Authentication Codes (MACs), authenticated encryption, wide block ciphers, etc. In this paper, we extend and improve upon existing design approaches and present a general framework for the construction of UHFs, relying only on the AES round function and 128-bit word-wide XORs. This framework, drawing inspiration from tweakable block ciphers design, allows both strong security arguments and extremely high throughput. The security with regards to differential cryptanalysis is guaranteed thanks to an optimized MILP modelling strategy, while performances are pushed to their limits with a deep study of the details of AES-NI software implementations. In particular, our framework not only takes into account the number of AES-round calls per message block, but also the very important role of XOR operations and the overall scheduling of the computations.We instantiate our findings with two concrete UHF candidates, both requiring only 2 AES rounds per 128-bit message block, and each used to construct two MACs. First, LeMac, a large-state primitive that is the fastest MAC as of today on modern Intel processors, reaching performances of 0.068 c/B on Intel Ice Lake (an improvement of 60% in throughput compared to the state-of-the-art). The second MAC construction, PetitMac, provides an interesting memory/throughput tradeoff, allowing good performances on many platforms.
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Mennink, Bart. "Keying Merkle-Damgård at the Suffix." IACR Transactions on Symmetric Cryptology 2025, no. 1 (2025): 70–96. https://doi.org/10.46586/tosc.v2025.i1.70-96.
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A classical way to turn a cryptographic hash function into a MAC (message authentication code) function is by concatenating key and message and interpreting the result as a tag. For the Merkle-Damgård hash function construction, the approach to prepend the key to the message is known to be insecure, as it is vulnerable to the length extension attack. This observation eventually resulted in the introduction of the HMAC construction. The alternative approach to append the key to the message, even though it already dates back to a work of Tsudik from 1992, has never been investigated in detail. In this work, we perform an in-depth treatment on the possibilities to design a MAC function from the Merkle-Damgård hash function construction by processing the key at the suffix. We formalize two constructions: the suffix keyed Merkle-Damgård construction that simply appends key to message, and the suffix blinded Merkle-Damgård construction that blinds the state before compressing the last message, much like the suffix keyed sponge construction (SuKS). We subsequently prove that both constructions are secure in the standard model under reasonable assumptions on the underlying compression function. We finally investigate the security of these constructions in the leaky setting, and demonstrate that the suffix keyed Merkle-Damgård construction is not leakage resilient, but the suffix blinded Merkle-Damgård construction is leakage resilient as long as an appropriate padding rule is adopted and as long as the underlying building blocks are processing secret data in a leakage resilient manner.
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Jolin, J. S., A. Theophilus, and A. Kathirvel. "Two-factor Mutual Authentication with Fingerprint and MAC Address Validation." International Journal of Computer Network and Information Security 16, no. 6 (2024): 56–68. https://doi.org/10.5815/ijcnis.2024.06.05.
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Mobile Ad hoc NETworks (MANET), unlike typical wireless networks, may be used spontaneously without the need for centralized management or network environment. Mobile nodes act as mediators to help multi-hop communications in such networks, and most instances, they are responsible for all connectivity tasks. MANET is a challenging endeavor because these systems can be attacked, which can harm the network. As a result, security concerns become a primary factor for these types of networks. This article aims to present an efficient two-factor smart card-based passcode authentication technique for securing legitimate users on an unprotected network. This scheme enables the password resetting feature. A secured mechanism for sharing keys is offered by using the hash function. We present a new two-factor mutual authentication technique based on an entirely new mechanism called the virtual smart card. Compared to authentication, the proposed method has fewer computation processes but is more time efficient since it is based on a hash function. Additionally, this approach is resistant to most attacker behaviors, such as Mutual authentication, Gateway node bypassing attacks, DoS attacks, replay attacks, Man in the middle attacks, and stolen smart device attacks. Experimental results validate the efficiency of this scheme, and its security is also analyzed.
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A., H. Poursoltan Mohammadi, Chehel Amirani M., and Faghihi F. "Presentation of an Algorithm for Secure Data Transmission based on Optimal Route Selection during Electromagnetic Interference Occurrence." International Journal of Electrical and Computer Engineering (IJECE) 8, no. 1 (2018): 259–70. https://doi.org/10.11591/ijece.v8i1.pp259-270.
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This paper proposes a comprehensive algorithm for secure data transmission via communication conductors considering route optimization, shielding and data authentication. Using of appropriate coding method causes more efficiency for suggested algorithm during electromagnetic field attack occurrence. In this paper, MOM simulation via FIKO software is done for field distribution. Due to critical situation of malfunctioning of data transferring, appropriate shield is designed and examined by shielding effectiveness (SE) criterion resulted of MOM simulation; finally to achieve reliability of data security, MAC hash function is used for space with field attack probability, turbo code is employed.
Dissertations / Theses on the topic "MAC hash function"
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Tomaz, Antonio Emerson Barros. "Resgate de autoria em esquemas de assinatura em anel." reponame:Repositório Institucional da UFC, 2014. http://www.repositorio.ufc.br/handle/riufc/10842.
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TOMAZ. A. E. B. Resgate de autoria em esquemas de assinatura em anel. 2014. 67 f. Dissertação (Mestrado em Engenharia de Teleinformática) - Centro de Tecnologia, Universidade Federal do Ceará, Fortaleza, 2014.<br>Submitted by Marlene Sousa (mmarlene@ufc.br) on 2015-02-27T18:29:04Z
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Previous issue date: 2014-05-23<br>The proposal presented in this thesis represents an expansion of the original concept of ring signature. A ring signature scheme allows a member of a group to publish a message anonymously, so that each member of the group can be considered the author of the message. The main idea of a ring signature is to guarantee the anonymity of the subscriber also ensure the authenticity of information, showing that the message came from one of the members of that group. This thesis presents a signature scheme based on (RIVEST et al., 2001), where the subscriber can later revoke anonymity presenting secret values that prove that he would only be able to generate such a signature. This property will be referred to here as rescue of authorship. The main difference to the proposal of Rivest et al. (2001) is presented before we even begin signature generation. The values used as input to the trapdoor function are message authentication codes - MACs generated by the HMAC algorithm, an algorithm for message authentication based on hash function collision resistant. This simple modification will allow, in the future, the subscriber to reveal itself as the true author of the message by showing the secret values to generate those MACs.<br>A proposta apresentada nesta dissertação representa uma expansão do conceito original de assinatura em anel. Um esquema de assinatura em anel permite que um membro de um grupo divulgue uma mensagem anonimamente, de tal forma que cada um dos membros do grupo seja considerado o possível autor da mensagem. A ideia principal de uma assinatura em anel é garantir o anonimato do assinante e ainda garantir a autenticidade da informação, mostrando que a mensagem partiu de um dos membros do referido grupo. Esta dissertação apresenta um esquema de assinatura em anel baseado no esquema de Rivest et al. (2001), em que o assinante pode, mais tarde, revogar seu anonimato apresentando valores secretos que provam que somente ele seria capaz de gerar tal assinatura. Esta propriedade será chamada aqui de resgate de autoria. A principal diferença em relação ao trabalho de Rivest et al. (2001) é apresentada antes mesmo de começar a geração da assinatura. Os valores utilizados como entrada para a função trapdoor serão códigos de autenticação de mensagem - MACs gerados pelo algoritmo HMAC, um algoritmo de autenticação de mensagem baseado em função hash resistente à colisão. Essa modificação simples permitirá que, no futuro, o assinante revele-se como o verdadeiro autor da mensagem apresentando os valores secretos que geraram os MACs.
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Marček, Ján. "Odposlech moderních šifrovaných protokolů." Master's thesis, Vysoké učení technické v Brně. Fakulta informačních technologií, 2012. http://www.nusl.cz/ntk/nusl-236427.
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This thesis deals with the introduction to the security mechanism.The procedure explains the basic concepts, principles of cryptography and security of modern protocols and basic principles that are used for information transmission network. The work also describes the most common types of attacks targeting the eavesdropping of communication. The result is a design of the eavesdropping and the implementation of an attack on the secure communication of the SSL protocol..The attacker uses a false certificate and attacks based on poisoning the ARP and DNS tables for this purpose. The thesis discusses the principles of the SSL protocol and methodology of attacks on the ARP and DNS tables.
Books on the topic "MAC hash function"
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Martin, Keith M. Data Integrity. Oxford University Press, 2017. http://dx.doi.org/10.1093/oso/9780198788003.003.0006.
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This chapter discusses cryptographic mechanisms for providing data integrity. We begin by identifying different levels of data integrity that can be provided. We then look in detail at hash functions, explaining the different security properties that they have, as well as presenting several different applications of a hash function. We then look at hash function design and illustrate this by discussing the hash function SHA-3. Next, we discuss message authentication codes (MACs), presenting a basic model and discussing basic properties. We compare two different MAC constructions, CBC-MAC and HMAC. Finally, we consider different ways of using MACs together with encryption. We focus on authenticated encryption modes, and illustrate these by describing Galois Counter mode.
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McManus, Alison M., and Neil Armstrong. Pulmonary function. Edited by Neil Armstrong and Willem van Mechelen. Oxford University Press, 2017. http://dx.doi.org/10.1093/med/9780198757672.003.0010.
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The principles of pulmonary ventilation are the same for children and adults. Ventilation adjusts to alterations in metabolic demand in the child; but for a given exercise intensity there is a greater ventilation when expressed relative to body mass and a higher energetic cost of breathing in the child compared to the adult. Limited evidence suggests child-adult differences may be a result of immature chemoreception, a greater drive to breathe, differences in airway dimensions, and the mechanical work of breathing. There are few studies investigating the dynamic ventilatory response to moderate intensity exercise and none to heavy or very heavy intensity exercise in the child. Little attention has been devoted to the developmental pattern of ventilatory control, although there is evidence of altered chemoreceptive modulation of breathing in the child. Considerable research will be necessary before we have a full appreciation of pulmonary function during exercise in the child.
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Burton, Derek, and Margaret Burton. Conservation and fish function. Oxford University Press, 2017. http://dx.doi.org/10.1093/oso/9780198785552.003.0016.
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The future for fish is a matter of concern. Individual fish may need specific conditions and are increasingly constrained by habitat changes and destruction, such as the reduction of wetlands. Pollution and temperature change affect fish negatively. It has recently been suggested that extinction rates for freshwater fish are very high. Generally, the wild fishery has no owner, ‘the tragedy of the commons’ may apply with nobody taking adequate responsibility. Increasing awareness is promoting conservation and conservation physiology. This can involve aquaculture, reducing the wild fisheries and captive breeding to rehabilitate stocks. Problems arise with overoptimistic views of bony fish reproductive capacity, a proportion may omit gametogenesis dependent on nutrition or temperature conditions. Conservation measures include establishing ‘marine protected areas’ which help recovery of fish populations. Support for conservation depends on education and knowledge-based decisions rather than inappropriate political compromises, particularly when international groups discuss the problems.
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Hurt, Teresa D., and Gordon Rakita. Style and Function. Praeger, 2000. http://dx.doi.org/10.5040/9798216020905.
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The topics of style and function within evolutionary archaeology have been the subject of great debate in the field of archaeology in general over the past two decades. Evolutionary archaeologists have a unique perspective on these concepts-one that has sometimes been misunderstood by archaeologists working within other theoretical perspectives. The dichotomy between style and function was first formulated in the late 1970s by Robert Dunnell and remains axiomatic within the theoretical perspective of evolutionary archaeology. The original definitions of style and function were grounded in biological evolutionary concepts regarding neutral variation versus variation that is subject to natural selection. Several chapters expand upon these concepts, and explore how Darwinian evolutionary theory may be used to understand the archaeological record. Other chapters demonstrate this application through empirical case studies. Dunnell provides a foreword introducing and re-examining his original thesis. This volume is the only text devoted to the topic of style and function within the literature of evolutionary archaeology. It provides not only theoretical discussions and augmentation, but also significant historical background regarding the development of the style/function distinction within archaeology. Moreover, it presents several case studies that provide examples of how evolutionary style and function may be applied to the prehistoric record.
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Powell, Jenny. Normal skin function. Edited by Patrick Davey and David Sprigings. Oxford University Press, 2018. http://dx.doi.org/10.1093/med/9780199568741.003.0243.
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In simplest terms, our skin is a layer that separates and protects us from the external environment. This assumes the skin is a passive covering to keep the insides safe and the outside out, and overlooks its enormous complexity. The skin is our largest organ and is constantly regenerating, but how efficiently it does so depends on a number of factors, some known, others unknown. It is an efficient mechanical barrier (designed for wear and repair), and a complex immunological membrane. It has a generous vascular, lymphatic, and nervous supply, all covering a considerable area. It has specialist structural and functional properties relating to specific areas, but also specialist cells within the layers of the skin. Most importantly, skin is the organ of display, an important part of social and sexual behaviour, immediately accessible to all, and often regarded as a barometer of the general state of health. Permanent scars inflicted on the skin may be a cause of great distress to the patient. Skin consists of a superficial layer, ‘the epidermis’ (concerned with producing protective keratin and a pigment called melanin), which adheres closely to the deeper layer, ‘the dermis’ (which provides the strength of the skin and houses the appendages), via the basement membrane. Loose connective tissue and fat underlie the dermis.
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Esler, Karen J., Anna L. Jacobsen, and R. Brandon Pratt. Form and Function of Mediterranean Shrublands. Oxford University Press, 2018. http://dx.doi.org/10.1093/oso/9780198739135.003.0006.
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The archetypal shrub type that dominates most of the regions that experience mediterranean-type climate (MTC) is an evergreen shrub with thick and leathery leaves (sclerophyllous). The occurrence of large stands of such shrubs in all MTC regions led early biogeographers to hypothesize that the MTC selects for this growth form and leaf type and that this had led to convergent evolution (see Chapters 1 and 2). This hypothesis has received considerable research interest and continues to be examined. In this chapter we consider the structure and physiology of these archetypal MTC region shrub species and examine evidence for convergent evolution in their structure and function. We also assess the key adaptive traits that enable the shrub species that compose mediterranean-type vegetation (MTV) communities to thrive in MTC regions.
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Aguilar-Torres, Río. Assessment of left atrial function. Oxford University Press, 2011. http://dx.doi.org/10.1093/med/9780199599639.003.0010.
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The left atrium (LA) plays an important role in cardiovascular performance, not only as a mechanical contributor, elastic reservoir, and a primer for left ventricular filling, but also as a participant in the regulation of intravascular volume through the production of atrial natriuretic peptide.Although LA diameter in the parasternal long-axis view has been routinely employed, LA volume is a more robust marker for predicting events than LA areas or diameters. The assessment of LA performance based on two-dimensional volumetrics, Doppler evaluation of mitral, pulmonary vein flow, and annular tissue Doppler, as well as deformation imaging techniques, may provide incremental information for prognostic purposes and for the evaluation of severity and duration of conditions associated with LA overload.The aims of this chapter are to explain the basics of LA function, and to describe the role of Doppler echocardiography techniques, and how to implement them, for the non-invasive evaluation of LA in clinical practice.
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Badano, Luigi P., and Denisa Muraru. Assessment of right heart function and haemodynamics. Oxford University Press, 2011. http://dx.doi.org/10.1093/med/9780199599639.003.0011.
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Assessment of right ventricular (RV) size, function, and haemodynamics has been challenging because of its unique cavity geometry. Conventional two-dimensional assessment of RV function is often qualitative. Doppler methods involving tricuspid inflow and pulmonary artery flow velocities, which are influenced by changes in pre- and afterload conditions, may not provide robust prognostic information for clinical decision making. Recent advances in echocardiographic assessment of the RV include tissue Doppler imaging, speckle-tracking imaging, and volumetric three-dimensional imaging, but they need specific training, expensive dedicated equipment, and extensive clinical validation. However, assessment of RV function is crucial, especially in patients with signs of right-sided failure and those with congenital or mitral valve diseases. This chapter aims to address the role of the various echocardiographic modalities used to assess RV and pulmonary vascular bed function. Special emphasis has been placed on technical considerations, limitations, and pitfalls of image acquisition and analysis.
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Voilliot, Damien, Jaroslaw D. Kasprzak, and Eduardo Bossone. Diseases with a main influence on right ventricular function. Oxford University Press, 2016. http://dx.doi.org/10.1093/med/9780198726012.003.0060.
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As an important and independent predictive factor of morbidity and mortality, right ventricular (RV) function should be carefully assessed in patients with chronic obstructive lung disease, lung fibrosis, liver cirrhosis, or obesity. RV assessment requires a complete study of the ‘RV-pulmonary circulation unit’ with estimation of RV preload, RV intrinsic contractility, and RV afterload. Therefore, estimation of pulmonary arterial pressure, pulmonary vascular resistance, and left ventricular systolic and diastolic function should be included in this evaluation, in addition to conventional RV systolic function assessment. Three-dimensional echocardiography has emerged as an interesting tool in RV assessment and exercise echocardiography may be interesting in the risk stratification of patients.
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Hinks, Anne, and Wendy Thomson. Genetics of juvenile rheumatic diseases. Oxford University Press, 2013. http://dx.doi.org/10.1093/med/9780199642489.003.0043.
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Juvenile rheumatic diseases are heterogeneous, complex genetic diseases; to date only juvenile idiopathic arthritis (JIA) has been extensively studied in terms of identifying genetic risk factors. The MHC region is a well-established risk factor but in the last few years candidate gene and genome-wide association studies have been utilized in the search for non-HLA risk factors. There are now an additional 12 JIA susceptibility loci with evidence for association in more than one study. In addition, some subtype-specific associations are emerging. These risk loci now need to be investigated further using fine-mapping strategies and then appropriate functional studies to show how the variant alters the gene function. This knowledge will not only lead to a better understanding of disease pathogenesis for juvenile rheumatic diseases but may also aid in the classification of these heterogeneous diseases. It may identify new pathways for potential therapeutic targets and help in the prediction of disease outcome and response to treatment.
Book chapters on the topic "MAC hash function"
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Shin, Sang Uk, Kyung Hyune Rhee, Dae Hyun Ryu, and Sang Jin Lee. "A new hash function based on MDx-family and its application to MAC." In Public Key Cryptography. Springer Berlin Heidelberg, 1998. http://dx.doi.org/10.1007/bfb0054028.
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Preneel, Bart, and Paul C. van Oorschot. "MDx-MAC and Building Fast MACs from Hash Functions." In Advances in Cryptology — CRYPT0’ 95. Springer Berlin Heidelberg, 1995. http://dx.doi.org/10.1007/3-540-44750-4_1.
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Wagner, Urs, and Thomas Lugrin. "Hash Functions." In Trends in Data Protection and Encryption Technologies. Springer Nature Switzerland, 2023. http://dx.doi.org/10.1007/978-3-031-33386-6_5.
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AbstractHash functions are one-way functions that map arbitrary-length input to fixed-length output. Moreover, they have many cryptographic applications, such as integrity checks, password storage, and signatures. Cryptographic hash functions have some additional properties that can be formulated as hard problems: pre-image resistance, second pre-image resistance, and collision resistance. A significant technological development in this area is unlikely. Standardized hash functions are considered secure, and open-source implementations can be used at no cost. To conclude, the security properties required from hash functions depend on the intended purpose.
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Duval, Sébastien, and Gaëtan Leurent. "Lightweight MACs from Universal Hash Functions." In Smart Card Research and Advanced Applications. Springer International Publishing, 2020. http://dx.doi.org/10.1007/978-3-030-42068-0_12.
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Preneel, B. "Hash functions and MAC algorithms based on block ciphers." In Crytography and Coding. Springer Berlin Heidelberg, 1997. http://dx.doi.org/10.1007/bfb0024473.
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Shin, Sang Uk, Kyung Hyune Rhee, and Jae Woo Yoon. "Hash Functions and the MAC Using All-or-Nothing Property." In Public Key Cryptography. Springer Berlin Heidelberg, 1999. http://dx.doi.org/10.1007/3-540-49162-7_21.
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Sheen, Raymond L. "Applying Value Engineering Function Analysis to the Process for Building Disassembly and the Recovery of Wood and Timber for Construction." In Lecture Notes in Civil Engineering. Springer Nature Switzerland, 2025. https://doi.org/10.1007/978-3-031-69626-8_153.
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AbstractThe United Nations published a report in May 2023 that highlighted circularity concepts in wood construction. They noted a problem of resistance to deconstruction with the intention of reusing wood elements. That resistance is partly due to the perception of the value, or rather lack of value, within the deconstruction process. However, if deconstruction can disassemble a building and recover the wood elements, it has created a valuable commodity. Value engineering principles can be used to analyze a process or service to maximize value. Value engineering has been applied in the construction industry but not to evaluate the deconstruction process. In this study, the value engineering functional analysis is applied to the process of disassembling a building and the recovery of wood and timber for reuse in the construction industry. The Function Analysis System Technique (FAST), a core element of value engineering, is used to identify primary and secondary functions. These functions are mapped onto the typical process used in building disassembly and recovery of wood and timber elements. The result is a process map that shows the contribution of the value-added steps in the process and identifies the non-value-added steps in the process. These results can be used to improve the design of disassembly and recovery processes to ensure the focus of the deconstruction process is on the value-added effort and that resources allocated to non-value-added efforts are minimized.
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Reich, Sebastian. "Particle-Based Algorithm for Stochastic Optimal Control." In Mathematics of Planet Earth. Springer Nature Switzerland, 2024. http://dx.doi.org/10.1007/978-3-031-70660-8_11.
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AbstractThe solution to a stochastic optimal control problem can be determined by computing the value function from a discretization of the associated Hamilton–Jacobi–Bellman equation. Alternatively, the problem can be reformulated in terms of a pair of forward-backward SDEs, which makes Monte–Carlo techniques applicable. More recently, the problem has also been viewed from the perspective of forward and reverse time SDEs and their associated Fokker–Planck equations. This approach is closely related to techniques used in diffusion-based generative models. Forward and reverse time formulations express the value function as the ratio of two probability density functions; one stemming from a forward McKean–Vlasov SDE and another one from a reverse McKean–Vlasov SDE. In this chapter, we extend this approach to a more general class of stochastic optimal control problems and combine it with ensemble Kalman filter type and diffusion map approximation techniques in order to obtain efficient and robust particle-based algorithms.
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Mani, Varghese. "Orthognathic Surgery for Mandible." In Oral and Maxillofacial Surgery for the Clinician. Springer Singapore, 2021. http://dx.doi.org/10.1007/978-981-15-1346-6_68.
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AbstractMandible, a horseshoe shaped bone of the facial skeleton, is one of the sturdy bones in humans. Prominent chin is a unique feature of anatomically modern man in comparison with his anthropological ancestors. The simian shelf has reduced to two genial tubercles to which two muscles are attached. The neck of the condyle has narrowed and acts as a buffer to budge by fracture if there is a severe force on the prominent chin. These evolutionary changes facilitated increased space for the tongue as men started articulation. It articulates with the temporal bone by two inter-dependent Temporo-mandibular joints. Mandible is important in both function and aesthetics.Mandible can be cut into multiple pieces and re-arranged and fixed to achieve aesthetic and functional changes. Facial bones have a tremendous capacity to regenerate and heal provided proper blood supply is ensured to the cut segments. Ostoetomies of the mandible can be done on ramus, body, chin, dento-alveolar region, inferior border, etc. Most of these procedures are done intraorally. Technological advancements have aided orthognathic surgery at large. This chapter envisages to elaborate different techniques of osteotomy of mandible.
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Laurent, Théo, Meven Lennon-Bertrand, and Kenji Maillard. "Definitional Functoriality for Dependent (Sub)Types." In Programming Languages and Systems. Springer Nature Switzerland, 2024. http://dx.doi.org/10.1007/978-3-031-57262-3_13.
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AbstractDependently typed proof assistant rely crucially on definitional equality, which relates types and terms that are automatically identified in the underlying type theory. This paper extends type theory with definitional functor laws, equations satisfied propositionally by a large class of container-like type constructors $$F : {\text {Type}}\rightarrow {\text {Type}}$$ F : Type → Type , equipped with a $$\textrm{map}_{F} {{\,\mathrm{:}\,}}(A \rightarrow B) \rightarrow F\,A \rightarrow F\,B$$ map F : ( A → B ) → F A → F B , such as lists or trees. Promoting these equations to definitional ones strengthens the theory, enabling slicker proofs and more automation for functorial type constructors. This extension is used to modularly justify a structural form of coercive subtyping, propagating subtyping through type formers in a map-like fashion. We show that the resulting notion of coercive subtyping, thanks to the extra definitional equations, is equivalent to a natural and implicit form of subsumptive subtyping. The key result of decidability of type-checking in a dependent type system with functor laws for lists has been entirely mechanized in Coq.
Conference papers on the topic "MAC hash function"
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Benmbarak, Omessead, Anis Naanaa, and Sadok Elasmi. "Security Evaluation of a Novel MAC Based on Hash Functions and 6D Chaotic Maps." In 2024 IEEE Eleventh International Conference on Communications and Networking (ComNet). IEEE, 2024. https://doi.org/10.1109/comnet64071.2024.10987255.
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Jones, R. H., C. H. Henager, C. A. Lewinsohn, and E. P. Simonen. "Measurement and Modeling of Environmentally Assisted Cracking of High-Temperature SiC/SiC Composites." In CORROSION 2002. NACE International, 2002. https://doi.org/10.5006/c2002-02419.
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Abstract The subcritical crack growth process that controls cracking of SiC/SiC composites at elevated temperatures is a function of temperature, stress, environment, loading mode and time. These processes include oxidation embrittlement (OE) that dominates in high oxygen environments, interphase removal (IR) that dominates in intermediate environments, viscous sliding (VS) that dominates at high temperatures and oxygen concentrations, fiber relaxation (FR) that dominates in low oxygen environments, and fiber-stress rupture (SR) that dominates a high temperatures. In nuclear environments, other processes become active such as irradiation enhanced creep that extends the FR regime to temperatures substantially below that for thermally activated creep. A crack growth mechanism map depicting the temperature, oxygen concentration and time regimes over which these processes dominate has been developed and will be described. The development of this map required that the crack growth mechanism first be determined and modeled and then the rules governing the boundary between these regimes defined.
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Sihite, Alfonso Brolin, and Muhammad Salman. "E-Voting and e-Recap Verification and Validation Schemes for Indonesia Utilizing Cryptographic Hash Function Message Authentication Codes (MAC) and Public Key Infrastructure (PKI)." In 2019 International Conference on Informatics, Multimedia, Cyber and Information System (ICIMCIS). IEEE, 2019. http://dx.doi.org/10.1109/icimcis48181.2019.8985212.
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Yixue Zhao. "Ad Hoc Networks key cluster management solution based on the hash function." In 2012 International Conference on Measurement, Information and Control (MIC). IEEE, 2012. http://dx.doi.org/10.1109/mic.2012.6273283.
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Varga, Domonkos, and Tamas Sziranyi. "Fast content-based image retrieval using convolutional neural network and hash function." In 2016 IEEE International Conference on Systems, Man, and Cybernetics (SMC). IEEE, 2016. http://dx.doi.org/10.1109/smc.2016.7844637.
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Hsieh, Shang-Lin, Chuan-Ren Chen, and Chun-Che Chen. "A duplicate image detection scheme using hash functions for database retrieval." In 2010 IEEE International Conference on Systems, Man and Cybernetics - SMC. IEEE, 2010. http://dx.doi.org/10.1109/icsmc.2010.5642432.
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Tyler, Christopher W., and Russell D. Hamer. "Photokinetic Analysis of Primate Cone Responses Implies Qualitative Differences from Rod Transduction." In Vision Science and its Applications. Optica Publishing Group, 1995. http://dx.doi.org/10.1364/vsia.1995.ma1.
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Diagnosis of functional disorders of the human retina is based on indirect measures of retinal function, such as psychophysical response functions and electroretinography. Interpretation of the data obtained by such measures requires an accurate model of the processes underlying the retinal responses. Recent progress in this regard has been made by Hood and Birch (1993) and others for rod function, but a comprehensive model for the nonlinear behavior of human cone responses has not been attempted.
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Wang, Sen, Donghai Jin, Xingmin Gui, and Xiaoheng Liu. "The Formula of Discharge Coefficient of the Cooling Hole in the Combustion Chamber for a Uniform Penetration Boundary Method." In ASME Turbo Expo 2020: Turbomachinery Technical Conference and Exposition. American Society of Mechanical Engineers, 2020. http://dx.doi.org/10.1115/gt2020-14567.
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Abstract At present, researches on the discharge coefficient of the combustion chamber cooling holes are mostly based on the experimental study of the porous plates considering various geometric structures under different flow conditions. In this method, the average discharge coefficients of multiple holes are obtained. Since the discharge coefficient will be applied to the numerical simulation, it is important to obtain an accurate formula for each cooling hole. Therefore, the discharge coefficient will be associated with some local aerodynamic parameters around the cooling holes and geometric parameters of the cooling holes. In this paper, the geometric parameters consist of length-to-diameter ratio (L/d) and inclination angle (α). The aerodynamic parameters cover the Mach number of cooling flow and mainstream (Mac, Mam), characterizing the flow feature, and the pressure ratio (π) which associates the cooling flow with the mainstream. The purpose of this paper is to study the discharge coefficient of a single circular hole with variable geometries under a cold condition of a combustion chamber, which has low crossflow and low-pressure ratio on both sides of the hole. In this environment, according to the research results, the discharge coefficient is sensitive to the cooling flow Mach number, length-to-diameter ratio and pressure ratio (π ≈ 1.05). Discharge coefficient decreases with L/d linearly, conforms the quadratic function with Mac and changes complexly at π ≈ 1.05. Other parameters have little effect on the discharge coefficient. The data for discharge coefficient of the cylindrical hole considering different parameters is obtained through numerical simulation and the correlations summarized by these data are valid for the following ranges: L/d = 3∼12, α = 20°∼45°, Mac = 0.05∼0.15, Mam = 0∼0.1, π = 1.05∼1.15. Compared with the CFD data, the prediction formula has a maximum error of less than 3% and a mean absolute error of 0.78%.
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Jude, JA, C. Johnson, J. Solway, TF Walseth, and MS Kannan. "Elevated CD38 Expression and Function in Asthmatic Human Airway Smooth Muscle (HASM) Cells." In American Thoracic Society 2009 International Conference, May 15-20, 2009 • San Diego, California. American Thoracic Society, 2009. http://dx.doi.org/10.1164/ajrccm-conference.2009.179.1_meetingabstracts.a3893.
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Mead, Carver. "Potential and Limitations of VLSI." In Optical Computing. Optica Publishing Group, 1985. http://dx.doi.org/10.1364/optcomp.1985.ma2.
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The VLSI Technology, as we know it, has the potential of creating systems with 1010 interconnected active devices on a single silicon wafer. Each device can evaluate an interesting function every 10−10 seconds. The awesome functional capability of such an arrangement is not matched by a corresponding communication bandwidth. Even at present complexity, designs are severely restricted by wiring congestion and delays due to wiring capacitance. The technology is complementary to optical systems, in which communication is fast and abundant, but non-linear functions are slower and more costly. A hybrid technology organized to take advantage of the strengths of both VLSI and optics could have a revolutionary impact on system design.
Reports on the topic "MAC hash function"
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Matthews, Lisa, Guanming Wu, Robin Haw, et al. Illuminating Dark Proteins using Reactome Pathways. Reactome, 2022. http://dx.doi.org/10.3180/poster/20221027matthews.
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Diseases are often the consequence of proteins or protein complexes that are non-functional or that function improperly. An active area of research has focused on the identification of molecules that can interact with defective proteins and restore their function. While 22% percent of human proteins are estimated to be druggable, less than fifteen percent are targeted by FDA-approved drugs, and the vast majority of untargeted proteins are understudied or so-called "dark" proteins. Elucidation of the function of these dark proteins, particularly those in commonly drug-targeted protein families, may offer therapeutic opportunities for many diseases. Reactome is the most comprehensive, open-access pathway knowledgebase covering 2585 pathways and including 14246 reactions, 11088 proteins, 13984 complexes, and 1093 drugs. Placing dark proteins in the context of Reactome pathways provides a framework of reference for these proteins facilitating the generation of hypotheses for experimental biologists to develop targeted experiments, unravel the potential functions of these proteins, and then design drugs to manipulate them. To this end, we have trained a random forest with 106 protein/gene pairwise features collected from multiple resources to predict functional interactions between dark proteins and proteins annotated in Reactome and then developed three scores to measure the interactions between dark proteins and Reactome pathways based on enrichment analysis and fuzzy logic simulations. Literature evidence via manual checking and systematic NLP-based analysis support predicted interacting pathways for dark proteins. To visualize dark proteins in the context of Reactome pathways, we have also developed a new website, idg.reactome.org, by extending the Reactome web application with new features illustrating these proteins together with tissue-specific protein and gene expression levels and drug interactions.
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Filiz, Ibrahim, Jan René Judek, Marco Lorenz, and Markus Spiwoks. Einhorn, Yeti, Nessie und der neoklassische Markt – Legenden und empirische Evidenz. Sonderforschungsgruppe Institutionenanalyse, 2022. http://dx.doi.org/10.46850/sofia.9783947850020.
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The neoclassical market model still has a decisive influence on important economic policy decisions today. A central role in this model is played by the formation of equilibrium prices, where aggregate supply functions and aggregate demand functions meet. We examine whether equilibrium prices are actually formed. For this purpose, we analyse 2,217 prices for homogeneous products that were collected by students between October 2020 and May 2022 in stationary and online retail. In 143 of 146 cases, no equilibrium price is found. The percentage price range is regularly over 100%. The presumed steering function of an equilibrium price does not materialise. The establishment of market mechanisms for the efficient solution of economic problems must therefore be questioned.
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Ziesemer, Thomas. Endogenous R&D elasticities of productivity functions and BERD bias: Explorations of functional coefficient regressions. UNU-MERIT, 2025. https://doi.org/10.53330/hgya6809.
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Macroeconomic productivity is modelled as a Cobb-Douglas function of private and public R&D stocks in recent literature. The slope parameters of a growth rate version may change over time and with circumstances. Using the method of functional-coefficient regression, we show that human capital, GDP (per worker), services and defence R&D (both % GDP), lags of domestic and foreign private and public R&D, and lagged labour-augmenting technical change, all in growth rates, change the elasticities of productivity. The result is a panel data set of regression coefficients representing elasticities of productivity. Eventually, the panel average of the productivity elasticities of domestic and foreign private R&D goes to constant values; elasticities of public R&D go down slightly. This may contribute to an explanation of the productivity slowdown and why private R&D has been expanded relative to public R&D in recent years.
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Lers, Amnon, and Pamela J. Green. LX Senescence-Induced Ribonuclease in Tomato: Function and Regulation. United States Department of Agriculture, 2003. http://dx.doi.org/10.32747/2003.7586455.bard.
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Natural leaf senescence, which occurs even when growth conditions are near optimal, has a negative influence on yield. Postharvest induced senescence contributes to the losses of quality in flowers, foliage, and vegetables. Strategies designed to control the senescence process in crop plants could therefore have great applied significance. However, the successful design of such strategies requires a better insight into the senescence machinery and control in higher plants. A main feature of senescence is the hydrolysis of macromolecules by hydrolases of various types such as ribonucleases (RNases) and proteases. Previously we had identified and characterized the tomato LX RNase gene demonstrating its transcript to be highly and specifically induced during senescence. This reported study was focused on LX but also had broadened our research to other senescence-associated nucleic acids degrading enzymes to learn about their function and the regulation of their encoding genes. Beside tomato we used parsley and Arabidopsis for the study of: the bi-functional nuclease which has a role in senescence. The study of different senescence- associated nucleases in few plant systems will allow a more general view on function and regulation of these enzymes in senescence. The specific original proposed objectives included: 1. Study the consequences of alterations in LX RNase level on tomato leaf senescence and general development; 2. Analyze stimuli which may participate in senescence-specific activation of the LX gene; 3. Clone the senescence-associated BFNI nuclease gene homologue from tomato. 4. Further characterize the sequences required for senescence-specific gene expression. Homozygous transgenic plants in which LX gene was either inhibited or over-expressed were generated. In both of these LX mutated plants no major phenotypic consequences were observed, which may suggests that LX is not essential for plant growth under optimal growth conditions. Lack of any abnormalities in the LX over-expressing lines suggests that special system exist to allow function of the RNase only when needed. Detailed analyses of growth under stress and consequences to RNA metabolism are underway. We have analyzed LX expression on the protein level demonstrating that it is involved also in petal senescing. Our results suggest that LX is responding to complex regulation involving developmental, organ dependent factors and responds differently to hormonal or environmental stimuli in the different plant organs. The cloned 1.4 kb promoter was cloned and its analysis revealed that probably not all required elements for senescence induction are included. Biochemical analysis of senescence-associated be-functional nucleases in the different plants, tomato, parsley and Arabidopsis, suggests they belong to a sub-class within the type I plant nucleases. The parsley PcNUC1/2 nuclease protein was purified from senescing leaves its and activity was studied in vitro revealing endo-, double strand, nucleolytic activity and exo-nucleolytic activity. Its encoding gene was cloned and found to be induced on the mRNA level. The promoter of the related Arabidopsis BFNI nuclease was shown in both tomato and Arabidopsis to be able and direct senescence-specific expression suggesting that, at least part, the gene is regulated on the transcriptional level and that the mechanism for this senescence-specific regulation is conserved between different plants. Few plants in which the BFNI gene is mutated were identified which are subjected now to detailed analysis. Our results suggest that the senescence-related nucleic acid degrading enzymes share similarities in both function and regulation between different plants and possibly have important functions in processes un-related to senescence. Still, the function of these enzymes, at least in some cases is not essential to plant development under optimal growth conditions. We are now at the stage which permits in depth investigation of the specific functions and mode of molecular regulation of senescence-associated nucleases with the aid of the research tools developed. The isolated senescence-specific promoter, shown to be active in heterologous plant system, could be utilized in agricultural-related biotechnological applications for retardation of senescence.
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Gutierrez-Arias, Ruvistay, Camila González-Mondaca, Vinka Marinkovic-Riffo, Marietta Ortiz-Puebla, Fernanda Paillán-Reyes, and Pamela Seron. Considerations for ensuring safety during telerehabilitation of people with stroke. A protocol for a scoping review. INPLASY - International Platform of Registered Systematic Review and Meta-analysis Protocols, 2022. http://dx.doi.org/10.37766/inplasy2022.9.0104.
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Review question / Objective: To summarise measures or aspects targeted at reducing the incidence of adverse events during the delivery of exercise interventions through telerehabilitation in patients after stroke. Background: The sequelae in people with stroke are diverse. Regarding physical function post-stroke, functional impairment of the upper and lower extremities is common, which may be due to weakness or paralysis, sensory loss, spasticity, and abnormal motor synergies. In addition, a near 15% prevalence of sarcopenia has been found in people with stroke. Gait impairment has been observed in a high percentage of people with stroke, a dysfunction that may persist despite rehabilitation. More than 50% of people with stroke may experience limitations in activities such as shopping, housework, and difficulty reintegrating into community life within 6 months. These restrictions can result in a diminished health-related quality of life.
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Küsters, Ralf, and Alex Borgida. What's in an Attribute? Consequences for the Least Common Subsumer. Aachen University of Technology, 1999. http://dx.doi.org/10.25368/2022.102.
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Functional relationships between objects, called 'attributes', are of considerable importance in knowledge representation languages, including Description Logics (DLs). A study of the literature indicates that papers have made, often implicity, different assumptions about the nature of attributes: whether they are always required to have a value, or whether they can be partial functions. The work presented here is the first explicit study of this difference for (sub-)classes of the CLASSIC DL, involving the same-as concept constructor. It is shown that although determining subsumption between concept descriptions has the same complexity (though requiring different algorithms), the story is different in the case of determining the least common subsumer (lcs). For attributes interpreted as partial functions, the lcs exists and can be computed relatively easily; even in this case our results correct and extend three previous papers about the lcs of DLs. In the case where attributes must have a value, the lcs may not exist, and even if it exists it may be of exponential size. Interestingly, it is possible to decide in polynomial time if the lcs exists.
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Levy, Maggie, Raymond Zielinski, and Anireddy S. Reddy. IQD1 Function in Defense Responses. United States Department of Agriculture, 2012. http://dx.doi.org/10.32747/2012.7699842.bard.
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The main objective of the proposed research was to study IQD1's mechanism of action and elucidate its role in plant protection. Preliminary experiments suggest that IQD1 binds CaM in a Ca²⁺-dependent manner and functions in general defense responses. We propose to identify proteins and genes that interact with IQD1, which may provide some clues to its mechanism of action. We also plan to dissect IQD1's integration in defense pathways and to study and modulate its binding affinity to CaM in order to enhance crop resistance. Our specific objectives were: (1) Analysis of IQD1's CaM-binding properties; (2) Identification of IQD1 targets;(3) Dissection of IQD1 integration into defense signaling pathways. Analysis of IQD1's CaM-binding properties defined four potential classes of sequences that should affect CaM binding: one is predicted to raise the affinity for Ca²⁺-dependent interaction but have no effect on Ca²⁺-independent binding; a second is predicted to act like the first mutation but eliminate Ca²⁺-independent binding; a third has no predicted effect on Ca²⁺-dependent binding but eliminates Ca²⁺-independent binding; and the fourth is predicted to eliminate or greatly reduce both Ca²⁺-dependent and Ca²⁺-independent binding. Following yeast two hybrid analysis we found that IQD1 interact with AtSR1 (Arabidopsis thalianaSIGNALRESPONSIVE1), a calcium/calmodulin-binding transcription factor, which has been shown to play an important role in biotic and abiotic stresses. We tested IQD1 interaction with both N-terminal or C-terminal half of SR1. These studies have uncovered that only the N-terminal half of the SR1 interacts with the IQD1. Since IQD1 has an important role in herbivory, its interaction with SR1 suggests that it might also be involved in plant responses to insect herbivory. Since AtSR1, like IQD1, is a calmodulin-binding protein and the mutant showed increased sensitivity to a herbivore, we analyzed WT, Atsr1 and the complemented line for the levels of GS to determine if the increased susceptibility of Atsr1 plants to T. ni feeding is associated with altered GS content. In general, Atsr1 showed a significant reduction in both aliphatic and aromatic GS levels as compared to WT. In order to study IQD1's molecular basis integration into hormone-signaling pathways we tested the epistatic relationships between IQD1 and hormone-signaling mutants. For that purpose we construct double mutants between IQD1ᴼXᴾ and mutants defective in plant-hormone signaling and GS accumulation. Epitasis with SA mutant NahG and npr1-1 and JA mutant jar1-1 suggested IQD1 function is dependent on both JA and SA as indicated by B. cinerea infection assays. We also verified the glucosinolate content in the crosses siblings and found that aliphatic GSL content is reduced in the double transgenic plants NahG:IQD1ᴼXᴾ as compare to parental lines while the aliphatic GSL content in the npr1-1:IQD1ᴼXᴾ and jar1-1: IQD1ᴼXᴾ double mutants was intimidated to the parental lines. This suggests that GSL content dependency on SA is downstream to IQD1. As a whole, this project should contribute to the development of new defense strategies that will improve crop protection and reduce yield losses and the amount of pesticides required; these will genuinely benefit farmers, consumers and the environment.
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Sonmez Turan, Meltem. Ascon-Based Lightweight Cryptography Standards for Constrained Devices. National Institute of Standards and Technology, 2025. https://doi.org/10.6028/nist.sp.800-232.
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In 2023, the National Institute of Standards and Technology (NIST) announced the selection of the Ascon family of algorithms designed by Dobraunig, Eichlseder, Mendel, and Schläffer to provide efficient cryptographic solutions for resource-constrained devices. This decision emerged from a rigorous, multi-round lightweight cryptography standardization process. The Ascon family includes a suite of cryptographic primitives that provide Authenticated Encryption with Associated Data (AEAD), hash function, and eXtendable Output Function (XOF) capabilities. The Ascon family is characterized by lightweight, permutation-based primitives and provides robust security, efficiency, and flexibility, making it ideal for resource-constrained environments, such as Internet of Things (IoT) devices, embedded systems, and low-power sensors. The family is developed to offer a viable alternative when the Advanced Encryption Standard (AES) may not perform optimally. This standard outlines the technical specifications and security properties of Ascon-AEAD128, Ascon-Hash256, Ascon-XOF128, and Ascon-CXOF128.
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Chamovitz, Daniel, and Albrecht Von Arnim. Translational regulation and light signal transduction in plants: the link between eIF3 and the COP9 signalosome. United States Department of Agriculture, 2006. http://dx.doi.org/10.32747/2006.7696515.bard.
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The COP9 signalosome (CSN) is an eight-subunit protein complex that is highly conserved among eukaryotes. Genetic analysis of the signalosome in the plant model species Arabidopsis thaliana has shown that the signalosome is a repressor of light dependent seedling development as mutant Arabidopsis seedlings that lack this complex develop in complete darkness as if exposed to light. These mutant plants die following the seedling stage, even when exposed to light, indicating that the COP9 signalosome also has a central role in the regulation of normal photomorphogenic development. The biochemical mode of action of the signalosome and its position in eukaryotic cell signaling pathways is a matter of controversy and ongoing investigation, and recent results place the CSN at the juncture of kinase signaling pathways and ubiquitin-mediated protein degradation. We have shown that one of the many CSN functions may relate to the regulation of translation through the interaction of the CSN with its related complex, eukaryotic initiation factor (eIF3). While we have established a physical connection between eIF3 subunits and CSN subunits, the physiological and developmental significance of this interaction is still unknown. In an effort to understand the biochemical activity of the signalosome, and its role in regulating translation, we originally proposed to dissect the contribution of "h" subunit of eIF3 (eIF3h) along the following specific aims: (i) Isolation and phenotypic characterization of an Arabidopsis loss-of-function allele for eIF3h from insertional mutagenesis libraries; (ii) Creation of designed gain and loss of function alleles for eIF3h on the basis of its nucleocytoplasmic distribution and its yeast-two-hybrid interactions with other eIF3 and signalosome partner proteins; (iii) Determining the contribution of eIF3h and its interaction with the signalosome by expressing specific mutants of eIF3h in the eIF3h- loss-of function background. During the course of the research, these goals were modified to include examining the genetic interaction between csn and eif3h mutations. More importantly, we extended our effort toward the genetic analysis of mutations in the eIF3e subunit, which also interacts with the CSN. Through the course of this research program we have made several critical scientific discoveries, all concerned with the apparent diametrically opposed roles of eIF3h and eIF3e. We showed that: 1) While eIF3e is essential for growth and development, eIF3h is not essential for growth or basal translation; 2) While eIF3e has a negative role in translational regulation, eIF3h is positively required for efficient translation of transcripts with complex 5' UTR sequences; 3) Over-accumulation of eIF3e and loss-of-function of eIF3h both lead to cop phenotypes in dark-grown seedlings. These results were published in one publication (Kim et al., Plant Cell 2004) and in a second manuscript currently in revision for Embo J. Are results have led to a paradigm shift in translation research – eIF3 is now viewed in all systems as a dynamic entity that contains regulatory subuits that affect translational efficiency. In the long-term agronomic outlook, the proposed research has implications that may be far reaching. Many important plant processes, including developmental and physiological responses to light, abiotic stress, photosynthate, and hormones operate in part by modulating protein translation [23, 24, 40, 75]. Translational regulation is slowly coming of age as a mechanism for regulating foreign gene expression in plants, beginning with translational enhancers [84, 85] and more recently, coordinating the expression of multiple transgenes using internal ribosome entry sites. Our contribution to understanding the molecular mode of action of a protein complex as fundamental as eIF3 is likely to lead to advances that will be applicable in the foreseeable future.
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Pell, Eva J., Sarah M. Assmann, Amnon Schwartz, and Hava Steinberger. Ozone Altered Stomatal/Guard Cell Function: Whole Plant and Single Cell Analysis. United States Department of Agriculture, 2000. http://dx.doi.org/10.32747/2000.7573082.bard.
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Original objectives (revisions from original proposal are highlighted) 1. Elucidate the direct effects O3 and H2O2 on guard cell function, utilizing assays of stomatal response in isolated epidermal peels and whole cell gas exchange. 2. Determine the mechanistic basis of O3 and H2O2 effects on the plasma membrane through application of the electrophysiological technique of patch clamping to isolated guard cells. 3. Determine the relative sensitivity of Israeli cultivars of economically important crops to O3 and determine whether differential leaf conductance responses to O3 can explain relative sensitivity to the air pollutant: transfer of technological expertise to Israel. Background to the topic For a long time O3 has been known to reduce gas exchange in plants; it has however been unclear if O3 can affect the stomatal complex directly. Ion channels are essential in stomatal regulation, but O3 has never before been shown to affect these directly. Major conclusions, solution, achievements 1. Ozone inhibits light-induced stomatal opening in epidermal peels isolated from Vicia faba, Arabidopsis thaliana and Nicotiana tabacum in V. faba plants this leads to reduced assimilation without a direct effect on the photosynthetic apparatus. Stomatal opening is more sensitive to O3 than stomatal closure. 2. Ozone causes inhibition of inward K+ channels (involved in stomatal opening) while no detectable effect is observed o the outward K+ channels (stomatal closure). 3. Hydrogen peroxide inhibits stomatal opening and induces stomatal closure in epidermal peels isolated from Vicia faba. 4. Hydrogen peroxide enhances stomatal closure by increasing K+ efflux from guard cells via outward rectifying K+ channels. 5. Based on epidermal peel experiments we have indirectly shown that Ca2+ may play a role in the guard cell response to O3. However, direct measurement of the guard cell [Ca2+]cyt did not show a response to O3. 6. Three Israeli cultivars of zucchini, Clarita, Yarden and Bareqet, were shown to be relatively sensitive to O3 (0.12 ml1-1 ). 7. Two environmentally important Israeli pine species are adversely affected by O3, even at 0.050 ml1-1 , a level frequently exceeded under local tropospheric conditions. P. brutia may be better equipped than P. halepensis to tolerate O3 stress. 8. Ozone directly affects pigment biosynthesis in pine seedlings, as well as the metabolism of O5 precursors, thus affecting the allocation of resources among various metabolic pathways. 9. Ozone induces activity of antioxidant enzymes, and of ascorbate content i the mesophyll and epidermis cells of Commelina communis L. Implications, both scientific and agricultural We have improved the understanding of how O3 and H2O2 do affect guard cell and stomatal function. We have shown that economical important Israeli species like zucchini and pine are relatively sensitive to O3.