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Strengthening Access Control Encryption [chapter]

Christian Badertscher, Christian Matt, Ueli Maurer
<span title="">2017</span> <i title="Springer International Publishing"> <a target="_blank" rel="noopener" href="https://fatcat.wiki/container/2w3awgokqne6te4nvlofavy5a4" style="color: black;">Lecture Notes in Computer Science</a> </i> &nbsp;
Access control encryption (ACE) was proposed by Damgård et al. to enable the control of information flow between several parties according to a given policy specifying which parties are, or are not, allowed to communicate. By involving a special party, called the sanitizer, policy-compliant communication is enabled while policy-violating communication is prevented, even if sender and receiver are dishonest. To allow outsourcing of the sanitizer, the secrecy of the message contents and the
more &raquo; ... ity of the involved communication partners is guaranteed. This paper shows that in order to be resilient against realistic attacks, the security definition of ACE must be considerably strengthened in several ways. A new, substantially stronger security definition is proposed, and an ACE scheme is constructed which provably satisfies the strong definition under standard assumptions. Three aspects in which the security of ACE is strengthened are as follows. First, CCA security (rather than only CPA security) is guaranteed, which is important since senders can be dishonest in the considered setting. Second, the revealing of an (unsanitized) ciphertext (e.g., by a faulty sanitizer) cannot be exploited to communicate more in a policyviolating manner than the information contained in the ciphertext. We illustrate that this is not only a definitional subtlety by showing how in known ACE schemes, a single leaked unsanitized ciphertext allows for an arbitrary amount of policy-violating communication. Third, it is enforced that parties specified to receive a message according to the policy cannot be excluded from receiving it, even by a dishonest sender. Definition 2.1. An access control encryption (ACE) scheme E consists of the following five PPT algorithms: Setup: The algorithm Setup on input a security parameter 1 κ and a policy P : outputs a master secret key msk and sanitizer parameters sp. We implicitly assume that all keys include the finite message space M and the ciphertext spaces C, C . Key Generation: The algorithm Gen is deterministic and on input a master secret key msk , a role i ∈ [n], and the type sen, outputs an encryption key ek i ; on input msk , j ∈ [n], and the type rec, outputs a decryption key dk j . Encrypt: The algorithm Enc on input an encryption key ek i and a message m ∈ M, outputs a ciphertext c ∈ C. Sanitizer: The algorithm San on input sanitizer parameters sp and a ciphertext c ∈ C, outputs a sanitized ciphertext c ∈ C ∪ {⊥}. Decrypt: The algorithm Dec on input a decryption key dk j and a sanitized ciphertext c ∈ C , outputs a message m ∈ M ∪ {⊥}; on input dk j and ⊥, it outputs ⊥. For a probabilistic algorithm A, consider the experiment Exp ACE-corr E,A that given a security parameter 1 κ and a policy P , executes (sp, msk ) ← Setup(1 κ , P ), (m, i, j) ← A Gen(msk ,·,·) (sp), ek i ← Gen(msk , i, sen), and dk j ← Gen(msk , j, rec). We define the correctness advantage of A (for security parameter κ and policy P ) as Adv ACE-corr E,A := Pr P (i, j) = 1 ∧ Dec dk j , San(sp, Enc(ek i , m)) = m , where the probability is over the randomness in Exp ACE-corr E,A and the random coins of Enc, San, and Dec. 1 Remark. Correctness of an encryption scheme is typically not defined via a game with an adversary, but by requiring that decryption of an encryption of m yields m with probability 1. This perfect correctness requirement is difficult to achieve for ACE schemes and not necessary for applications because it is sufficient if a decryption error only occurs with negligible probability in 1 The scheme E can be called correct if Adv ACE-corr E,A is negligible for all efficient A. As mentioned in Section 2.2 , we do not state this as part of the definition since we follow a concrete security treatment.
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Composable and Robust Outsourced Storage [chapter]

Christian Badertscher, Ueli Maurer
<span title="">2018</span> <i title="Springer International Publishing"> <a target="_blank" rel="noopener" href="https://fatcat.wiki/container/2w3awgokqne6te4nvlofavy5a4" style="color: black;">Lecture Notes in Computer Science</a> </i> &nbsp;
The security of data outsourcing mechanisms has become a crucial aspect of today's IT infrastructures. Security goals range from ensuring storage integrity, condentiality, and access pattern hiding, to proofs of storage, proofs of ownership, and secure deduplication techniques. Despite sharing a common setting, previous security analyses of these tasks are often performed in dierent models and in a stand-alone fashion, which makes it hard to assess the overall security of a protocol or
more &raquo; ... on involving several security schemes. In this work, we ll this gap and provide a composable model to capture the above security goals. We instantiate the basic client-server setting in this model, where the goal of the honest client is to retain security in the presence of a malicious server. Three specic contributions of the paper, which may be of independent interest, are: 1. We present a novel and composable denition for secure and robust outsourcing schemes. Our denition is stronger than previous denitions for oblivious RAM or software protection, and assures strong security guarantees against active attacks. It not only assures that an attacker cannot learn the access pattern, but moreover assures resilience to errors and the prevention of targeted attacks to specic locations. We provide a protocol based on the well-known Path ORAM scheme achieving this strong security goal. We justify the need for such a strong notion in practice and show that several existing schemes cannot achieve this level of security. 2. We present a novel and composable denition for proofs of retrievability capturing the guarantee that a successful audit implies that the current server state allows the client to retrieve his data. As part of our study, we develop an audit mechanism, based on secure and robust outsourcing schemes, that is similar to the construction by Cash et al. (Eurocrpyt 2013), but is universally composable and fault-tolerant. 3. We assess the security of the standard challenge-response audit mechanism, in which the server has to compute a hash H(F ||c) on the le F concatenated with a uniformly random challenge c chosen by the client. Being concerned with composable security, we prove that this audit mechanism is not secure, even in the random oracle model, without assuming additional restrictions on the server behavior. The security of this basic audit scheme was implicitly assumed in Ristenpart et al. (Eurocrypt 2011). To complete the picture, we state the additional assumptions for this audit mechanism to be provably secure and investigate the (in)applicability of hash-function constructions in this setting.
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On Composable Security for Digital Signatures [chapter]

Christian Badertscher, Ueli Maurer, Björn Tackmann
<span title="">2018</span> <i title="Springer International Publishing"> <a target="_blank" rel="noopener" href="https://fatcat.wiki/container/2w3awgokqne6te4nvlofavy5a4" style="color: black;">Lecture Notes in Computer Science</a> </i> &nbsp;
A digital signature scheme (DSS), which consists of a keygeneration, a signing, and a verification algorithm, is an invaluable tool in cryptography. The first and still most widely used security definition for a DSS, existential unforgeability under chosen-message attack, was introduced by Goldwasser, Micali, and Rivest in 1988. As DSSs serve as a building block in numerous complex cryptographic protocols, a security definition that specifies the guarantees of a DSS under composition is needed.
more &raquo; ... Canetti (FOCS 2001, CSFW 2004 as well as Backes, Pfitzmann, and Waidner (CCS 2003) have described ideal functionalities for signatures in their respective composable-security frameworks. While several variants of these functionalities exist, they all share that the verification key and signature values appear explicitly. In this paper, we describe digital signature schemes from a different, more abstract perspective. Instead of modeling all aspects of a DSS in a monolithic ideal functionality, our approach characterizes a DSS as a construction of a repository for authentically reading values written by a certain party from certain assumed repositories, e.g., for transmitting verification key and signature values. This approach resolves several technical complications of previous simulation-based approaches, captures the security of signature schemes in an abstract way, and allows for modular proofs. We show that our definition is equivalent to existential unforgeability. We then model two example applications: (1) the certification of values via a signature from a specific entity, which with public keys as values is the core functionality of public-key infrastructures, and (2) the authentication of a session between a client and a server with the help of a digitally signed assertion from an identity provider. Single-sign-on mechanisms such as SAML rely on the soundness of the latter approach.
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Robust Authenticated Encryption and the Limits of Symmetric Cryptography [chapter]

Christian Badertscher, Christian Matt, Ueli Maurer, Phillip Rogaway, Björn Tackmann
<span title="">2015</span> <i title="Springer International Publishing"> <a target="_blank" rel="noopener" href="https://fatcat.wiki/container/2w3awgokqne6te4nvlofavy5a4" style="color: black;">Lecture Notes in Computer Science</a> </i> &nbsp;
Robust authenticated encryption (RAE) is a primitive for symmetric encryption that allows to flexibly specify the ciphertext expansion, i.e., how much longer the ciphertext is compared to the plaintext. For every ciphertext expansion, RAE aims at providing the best-possible authenticity and confidentiality. To investigate whether this is actually achieved, we characterize exactly the guarantees symmetric cryptography can provide for any given ciphertext expansion. Our characterization reveals
more &raquo; ... t only that RAE reaches the claimed goal, but also, contrary to prior belief, that one cannot achieve full confidentiality without ciphertext expansion. This provides new insights into the limits of symmetric cryptography. Moreover, we provide a rigorous treatment of two previously only informally stated additional features of RAE; namely, we show how redundancy in the message space can be exploited to improve the security and we analyze the exact security loss if multiple messages are encrypted with the same nonce.
<span class="external-identifiers"> <a target="_blank" rel="external noopener noreferrer" href="https://doi.org/10.1007/978-3-319-27239-9_7">doi:10.1007/978-3-319-27239-9_7</a> <a target="_blank" rel="external noopener" href="https://fatcat.wiki/release/n3ev654wa5hclooamdsv3u4nga">fatcat:n3ev654wa5hclooamdsv3u4nga</a> </span>
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Security Limitations of Classical-Client Delegated Quantum Computing [article]

Christian Badertscher, Alexandru Cojocaru, Léo Colisson, Elham Kashefi, Dominik Leichtle, Atul Mantri, Petros Wallden
<span title="2020-07-03">2020</span> <i > arXiv </i> &nbsp; <span class="release-stage" >pre-print</span>
Secure delegated quantum computing allows a computationally weak client to outsource an arbitrary quantum computation to an untrusted quantum server in a privacy-preserving manner. One of the promising candidates to achieve classical delegation of quantum computation is classical-client remote state preparation (RSP_CC), where a client remotely prepares a quantum state using a classical channel. However, the privacy loss incurred by employing RSP_CC as a sub-module is unclear. In this work, we
more &raquo; ... nvestigate this question using the Constructive Cryptography framework by Maurer and Renner (ICS'11). We first identify the goal of RSP_CC as the construction of ideal RSP resources from classical channels and then reveal the security limitations of using RSP_CC. First, we uncover a fundamental relationship between constructing ideal RSP resources (from classical channels) and the task of cloning quantum states. Any classically constructed ideal RSP resource must leak to the server the full classical description (possibly in an encoded form) of the generated quantum state, even if we target computational security only. As a consequence, we find that the realization of common RSP resources, without weakening their guarantees drastically, is impossible due to the no-cloning theorem. Second, the above result does not rule out that a specific RSP_CC protocol can replace the quantum channel at least in some contexts, such as the Universal Blind Quantum Computing (UBQC) protocol of Broadbent et al. (FOCS '09). However, we show that the resulting UBQC protocol cannot maintain its proven composable security as soon as RSP_CC is used as a subroutine. Third, we show that replacing the quantum channel of the above UBQC protocol by the RSP_CC protocol QFactory of Cojocaru et al. (Asiacrypt '19), preserves the weaker, game-based, security of UBQC.
<span class="external-identifiers"> <a target="_blank" rel="external noopener" href="https://arxiv.org/abs/2007.01668v1">arXiv:2007.01668v1</a> <a target="_blank" rel="external noopener" href="https://fatcat.wiki/release/2gb5qmsqt5fn5mfwak4aotxe2u">fatcat:2gb5qmsqt5fn5mfwak4aotxe2u</a> </span>
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Thomas Nestelberger, Jasper Boeddinghaus, Patrick Badertscher, Raphael Twerenbold, Christian Mueller
<span title="">2018</span> <i title="Elsevier BV"> <a target="_blank" rel="noopener" href="https://fatcat.wiki/container/ssdz5shjvrai3ijjkutdhctqam" style="color: black;">Journal of the American College of Cardiology</a> </i> &nbsp;
Thomas Nestelberger, MD Jasper Boeddinghaus, MD Patrick Badertscher, MD Raphael Twerenbold, MD *Christian Mueller, MD *Cardiovascular Research Institute Basel (CRIB) and Department of Cardiology  ...  Published by Elsevier. 1 . 1 Nestelberger T, Boeddinghaus J, Badertscher P, et al. Effect of definition on incidence and prognosis of type 2 myocardial infarction.  ... 
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High-sensitivity Cardiac Troponin: A Novel Window to the Heart

Patrick Badertscher, Christian Mueller
<span title="2017-10-05">2017</span> <i title="American Association for Clinical Chemistry (AACC)"> <a target="_blank" rel="noopener" href="https://fatcat.wiki/container/b3kmrecbc5hnhkzfkc3zkbultm" style="color: black;">Clinical Chemistry</a> </i> &nbsp;
The TEAMSTA study 2 (1 ), reported on in this issue of Clinical Chemistry, investigated the effect of 2 different antihypertensive treatments on blood concentrations of high-sensitivity cardiac troponin (hs-cTn) 3 , as a quantitative marker of cardiomyocyte injury, and B-type natriuretic peptide (BNP), as a quantitative marker of hemodynamic cardiac stress, in a randomized controlled trial. After 6 months of treatment, blood pressure was reduced by about 10 mmHg with similar effects in both
more &raquo; ... ps. hs-cTnT concentrations were measurable in 26.2% of the study population, while hs-cTnI was detected in 98.3%. hs-cTnI concentrations were significantly reduced from 4.6 to 4.2 ng/L in the overall population, 4.7 to 4.4 ng/L in the group containing an angiotensinreceptor blocker and a diuretic, and 4.6 to 4.0 ng/L in the group containing an angiotensin-receptor blocker and a calcium antagonist (all P Ͻ 0.001). No significant changes of hs-cTnT were observed. BNP and N-terminal-proBNP (NT-proBNP) concentrations decreased from 15.0 to 12.4 ng/L (P Ͻ 0.001) and 64.8 to 53.3 ng/L (P Ͻ 0.001), respectively, after 6 months. The authors concluded that blood pressure reduction was associated with a decrease of hs-cTnI, BNP, and NT-proBNP concentrations, which might represent a cardiovascular risk reduction. The TEAMSTA study extends and corroborates other recent pilot studies highlighting the enormous potential of well-characterized cardiac biomarker assays, particularly hs-cTn, beyond their established and approved indication (1-13 ). The clinical introduction of hs-cTn assays has provided a novel and unique in-vivo window to the heart, quantifying cardiomyocyte injury. While previously thought to be a phenomenon exclusive to acute myocardial infarction, cardiomyocyte injury has also recently been found to be present, to a varying extent, in patients with chronic cardio-vascular disorders such as heart failure, valvular and rhythmogenic heart disease, cardiomyopathy, stable coronary artery disease, left ventricular hypertrophy, and even in patients with arterial hypertension without left ventricular hypertrophy as well as completely healthy individuals (1-14 ) . The pathophysiological processes, other than acute myocardial ischemia, leading to cardiomyocyte injury as quantified by hs-cTn concentrations are incompletely understood, but are likely multifactorial. Irrespective of the predominant mechanisms present in the individual patient, cardiomyocyte injury and therefore hs-cTn concentrations seem to have a continuous and possibly a near-linear association with major adverse clinical events occurring years or even decades later including cardiovascular death, incident heart failure, stroke, and possibly myocardial infarction. The current study investigated the two most widely used hs-cTn assays: hs-cTnT (Elecsys) and hs-cTnI (Architect). While both seem to provide comparable diagnostic accuracy in the early diagnosis of acute myocardial infarction (10 -12 ), the even higher analytical sensitivity and associated ability to reliably quantify hs-cTn and its changes in the low-normal range render hs-cTnI the preferred tool when assessing patients with only small degrees of cardiomyocyte injury as, e.g., seen in patients with arterial hypertension, patients investigated for the presence or absence of exercise-induced myocardial ischemia, and healthy individuals in general (5-10 ). It is unknown and a matter of ongoing research to what extent these discrepancies relate to differences in the nature of the analytes cTnT and cTnI, the antibody combination of the hs-cTn assay used, or the analytical sensitivity achieved. It is also unknown whether the subtle difference in the detected cardiomyocyte injury by the high precision of the hs-cTnI assay within 6 months, 0.4 ng/L in the overall population, is clinically meaningful. Assuming that a particular hs-cTn blood concentration reflects a certain amount of cardiomyocyte injury and turnover, and that a healthy human heart is composed of a given number of cardiomyocytes, and that although likely existing, the potential for renewal of cardiomyocytes is limited, it would very likely be preferable to be in the group of persons with lower hs-cTn concentrations (1-14 ) . Assessing changes in hs-cTn and/or BNP/NT-proBNP concentrations within randomized controlled clinical trial is an attractive, simple, and inexpensive approach to delineate the effects of medical, behavioral, or interventional treatment on relatively well-defined
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Augmented Secure Channels and the Goal of the TLS 1.3 Record Layer [chapter]

Christian Badertscher, Christian Matt, Ueli Maurer, Phillip Rogaway, Björn Tackmann
<span title="">2015</span> <i title="Springer International Publishing"> <a target="_blank" rel="noopener" href="https://fatcat.wiki/container/2w3awgokqne6te4nvlofavy5a4" style="color: black;">Lecture Notes in Computer Science</a> </i> &nbsp;
Motivated by the wide adoption of authenticated encryption and TLS, we suggest a basic channel abstraction, an augmented secure channel (ASC), that allows a sender to send a receiver messages consisting of two parts, where one is privacy-protected and both are authenticityprotected. Working in the tradition of constructive cryptography, we formalize this idea and provide a construction of this kind of channel using the lower-level tool authenticated-encryption. We look at recent proposals on
more &raquo; ... 1.3 and suggest that the criterion by which their security can be judged is quite simple: do they construct an ASC? Due to this precisely defined goal, we are able to give a natural construction that comes with a rigorous security proof and directly leads to a proposal on TLS 1.3 that is provably secure.
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Bitcoin as a Transaction Ledger: A Composable Treatment [chapter]

Christian Badertscher, Ueli Maurer, Daniel Tschudi, Vassilis Zikas
<span title="">2017</span> <i title="Springer International Publishing"> <a target="_blank" rel="noopener" href="https://fatcat.wiki/container/2w3awgokqne6te4nvlofavy5a4" style="color: black;">Lecture Notes in Computer Science</a> </i> &nbsp;
Bitcoin is one of the most prominent examples of a distributed cryptographic protocol that is extensively used in reality. Nonetheless, existing security proofs are property-based, and as such they do not support composition. In this work we put forth a universally composable treatment of the Bitcoin protocol. We specify the goal that Bitcoin aims to achieve as a ledger functionality in the (G)UC model of Canetti et al. [TCC'07]. Our ledger functionality is weaker than the one recently proposed
more &raquo; ... by Kiayias, Zhou, and Zikas [EUROCRYPT'16], but unlike the latter suggestion, which is arguably not implementable given the Bitcoin assumptions, we prove that the one proposed here is securely UC realized under standard assumptions by an appropriate abstraction of Bitcoin as a UC protocol. We further show how known property-based approaches can be cast as special instances of our treatment and how their underlying assumptions can be cast in (G)UC without restricting the environment or the adversary. This is an extended version of a paper that appeared at
<span class="external-identifiers"> <a target="_blank" rel="external noopener noreferrer" href="https://doi.org/10.1007/978-3-319-63688-7_11">doi:10.1007/978-3-319-63688-7_11</a> <a target="_blank" rel="external noopener" href="https://fatcat.wiki/release/vus3ynfb6vcjhezblssndeutii">fatcat:vus3ynfb6vcjhezblssndeutii</a> </span>
<a target="_blank" rel="noopener" href="https://web.archive.org/web/20190220210042/http://pdfs.semanticscholar.org/293a/0401a4b6d2af30e8a4420d28ae8441a58932.pdf" title="fulltext PDF download" data-goatcounter-click="serp-fulltext" data-goatcounter-title="serp-fulltext"> <button class="ui simple right pointing dropdown compact black labeled icon button serp-button"> <i class="icon ia-icon"></i> Web Archive [PDF] <div class="menu fulltext-thumbnail"> <img src="https://blobs.fatcat.wiki/thumbnail/pdf/29/3a/293a0401a4b6d2af30e8a4420d28ae8441a58932.180px.jpg" alt="fulltext thumbnail" loading="lazy"> </div> </button> </a> <a target="_blank" rel="external noopener noreferrer" href="https://doi.org/10.1007/978-3-319-63688-7_11"> <button class="ui left aligned compact blue labeled icon button serp-button"> <i class="external alternate icon"></i> springer.com </button> </a>

Ouroboros Genesis

Christian Badertscher, Peter Gaži, Aggelos Kiayias, Alexander Russell, Vassilis Zikas
<span title="">2018</span> <i title="ACM Press"> <a target="_blank" rel="noopener" href="https://fatcat.wiki/container/rau5643b7ncwvh74y6p64hntle" style="color: black;">Proceedings of the 2018 ACM SIGSAC Conference on Computer and Communications Security - CCS &#39;18</a> </i> &nbsp;
Recently, Badertscher et al. [3] put forth the first composable analysis of Bitcoin, by proving that it implements, in a universally composable (UC) manner, an immutable transaction ledger.  ... 
<span class="external-identifiers"> <a target="_blank" rel="external noopener noreferrer" href="https://doi.org/10.1145/3243734.3243848">doi:10.1145/3243734.3243848</a> <a target="_blank" rel="external noopener" href="https://dblp.org/rec/conf/ccs/BadertscherGKRZ18.html">dblp:conf/ccs/BadertscherGKRZ18</a> <a target="_blank" rel="external noopener" href="https://fatcat.wiki/release/26olav7vungppgwhf425dkyuee">fatcat:26olav7vungppgwhf425dkyuee</a> </span>
<a target="_blank" rel="noopener" href="https://web.archive.org/web/20190218001220/https://eprint.iacr.org/2018/378.pdf" title="fulltext PDF download" data-goatcounter-click="serp-fulltext" data-goatcounter-title="serp-fulltext"> <button class="ui simple right pointing dropdown compact black labeled icon button serp-button"> <i class="icon ia-icon"></i> Web Archive [PDF] <div class="menu fulltext-thumbnail"> <img src="https://blobs.fatcat.wiki/thumbnail/pdf/d3/2b/d32b5152a56277bb777185997fbede380156673d.180px.jpg" alt="fulltext thumbnail" loading="lazy"> </div> </button> </a> <a target="_blank" rel="external noopener noreferrer" href="https://doi.org/10.1145/3243734.3243848"> <button class="ui left aligned compact blue labeled icon button serp-button"> <i class="external alternate icon"></i> acm.org </button> </a>

Grafting of α-tocopherol upon γ-irradiation in UHMWPE probed by model hydrocarbons

Remo P. Badertscher, Reto Lerf, Daniel Delfosse, Christian Adlhart
<span title="">2012</span> <i title="Elsevier BV"> <a target="_blank" rel="noopener" href="https://fatcat.wiki/container/svig2w6n3zgsvb7gyqyrbd26we" style="color: black;">Polymer degradation and stability</a> </i> &nbsp;
Acknowledgements Financial support by Mathys Ltd through a BSc grant for Remo Badertscher is gratefully acknowledged. We also thank Dr. Ivana Kroslakova for acquiring the MALDI-MS spectra.  ... 
<span class="external-identifiers"> <a target="_blank" rel="external noopener noreferrer" href="https://doi.org/10.1016/j.polymdegradstab.2012.07.040">doi:10.1016/j.polymdegradstab.2012.07.040</a> <a target="_blank" rel="external noopener" href="https://fatcat.wiki/release/okyh5avgujbixek5uvikldfhqe">fatcat:okyh5avgujbixek5uvikldfhqe</a> </span>
<a target="_blank" rel="noopener" href="https://web.archive.org/web/20180721162240/https://digitalcollection.zhaw.ch/bitstream/11475/2079/1/2012_Adlhart_Grafting_of_Tocopherol_upon_Irradiation_Polymer_Degradation_and_Stability.pdf" title="fulltext PDF download" data-goatcounter-click="serp-fulltext" data-goatcounter-title="serp-fulltext"> <button class="ui simple right pointing dropdown compact black labeled icon button serp-button"> <i class="icon ia-icon"></i> Web Archive [PDF] <div class="menu fulltext-thumbnail"> <img src="https://blobs.fatcat.wiki/thumbnail/pdf/9a/f5/9af55f8fc5e57123ac4d8fffe630c20f9a44222f.180px.jpg" alt="fulltext thumbnail" loading="lazy"> </div> </button> </a> <a target="_blank" rel="external noopener noreferrer" href="https://doi.org/10.1016/j.polymdegradstab.2012.07.040"> <button class="ui left aligned compact blue labeled icon button serp-button"> <i class="external alternate icon"></i> elsevier.com </button> </a>

Cardiomyopathy in newborns and infants: a broad spectrum of aetiologies and poor prognosis

Andrea Badertscher, Urs Bauersfeld, Urs Arbenz, Matthias R. Baumgartner, Albert Schinzel, Christian Balmer
<span title="">2008</span> <i title="Wiley"> <a target="_blank" rel="noopener" href="https://fatcat.wiki/container/7y2itco5zrfz5izvnrel6oymgm" style="color: black;">Acta Paediatrica</a> </i> &nbsp;
Aim: This study set out to describe the initial clinical findings, morbidity, mortality and aetiology of infant cardiomyopathy focusing on potential risk factors for an adverse outcome. Methods: We retrospectively analysed clinical and laboratory findings of all patients diagnosed at our institution from 1995 to 2004 with cardiomyopathy within their first year of life. Results: Of the 35 patients, cardiomyopathy was classified as dilated in 18, hypertrophic in 14 and unclassified in 3. The
more &raquo; ... logies were genetic syndromes (8), metabolic diseases (5), familial isolated cardiomyopathy (3) and myopathy (1). During a median follow-up of 1.5 years (range 0-9 years), 13 patients died from progressive heart failure and two underwent heart transplants. Estimated survival and freedom from transplant was 69, 66, 58 and 50% after 0.5, 1, 2 and 6 years, respectively. Patients with severe heart failure symptoms within the first month of life had significantly worse outcomes than patients without heart failure symptoms. Conclusion: High morbidity and poor prognosis result through progressive heart failure. Aetiology and clinical course are especially heterogeneous in infants. The most commonly identified aetiologies are genetic syndromes and metabolic diseases. A multidisciplinary approach is recommended for defining the aetiology and developing individual treatment strategies.
<span class="external-identifiers"> <a target="_blank" rel="external noopener noreferrer" href="https://doi.org/10.1111/j.1651-2227.2008.00957.x">doi:10.1111/j.1651-2227.2008.00957.x</a> <a target="_blank" rel="external noopener" href="https://www.ncbi.nlm.nih.gov/pubmed/18652581">pmid:18652581</a> <a target="_blank" rel="external noopener" href="https://fatcat.wiki/release/4spp4ynhybff7hw6qpz4nvap3e">fatcat:4spp4ynhybff7hw6qpz4nvap3e</a> </span>
<a target="_blank" rel="noopener" href="https://web.archive.org/web/20170922115942/http://www.zora.uzh.ch/id/eprint/28623/2/DissBadertscher_V.pdf" title="fulltext PDF download" data-goatcounter-click="serp-fulltext" data-goatcounter-title="serp-fulltext"> <button class="ui simple right pointing dropdown compact black labeled icon button serp-button"> <i class="icon ia-icon"></i> Web Archive [PDF] <div class="menu fulltext-thumbnail"> <img src="https://blobs.fatcat.wiki/thumbnail/pdf/01/98/0198bb9383499a57f1de7e257e48f341f0efc458.180px.jpg" alt="fulltext thumbnail" loading="lazy"> </div> </button> </a> <a target="_blank" rel="external noopener noreferrer" href="https://doi.org/10.1111/j.1651-2227.2008.00957.x"> <button class="ui left aligned compact blue labeled icon button serp-button"> <i class="external alternate icon"></i> Publisher / doi.org </button> </a>

Case report: electrical storm during induced hypothermia in a patient with early repolarization

Patrick Badertscher, Michael Kuehne, Beat Schaer, Christian Sticherling, Stefan Osswald, Tobias Reichlin
<span title="2017-11-15">2017</span> <i title="Springer Nature"> <a target="_blank" rel="noopener" href="https://fatcat.wiki/container/talwtajcjnc6phipdic6watona" style="color: black;">BMC Cardiovascular Disorders</a> </i> &nbsp;
Population based studies showed an association of early repolarization in the electrocardiogram (ECG) and a higher rate of sudden cardiac death presumably due to ventricular fibrillation. The triggers for ventricular fibrillation in patients with early repolarization are not fully understood. Case presentation: We describe the case of a young patient with a survived ventricular fibrillation arrest while asleep followed by multiple episodes of recurrent ventricular fibrillation. The admission
more &raquo; ... showed an early repolarization pattern with substantial J-point elevation in most of the ECG-leads. After initiation of a hypothermia protocol, the patient developed an electrical storm with multiple ventricular fibrillation episodes requiring multiple cardioversions. Intravenous isoproterenol infusion successfully suppressed the malignant arrhythmia. Conclusion: Hypothermia appears proarrhythmic in patients with early repolarization and may trigger ventricular fibrillation. This knowledge is particularly important when initiating temperature management protocols in patients after a survived cardiac arrest. During the acute phase of an early repolarization associated electrical storm, isoproterenol is the most effective treatment suppressing the ventricular fibrillation-inducing premature ventricular complexes at higher heart rates.
<span class="external-identifiers"> <a target="_blank" rel="external noopener noreferrer" href="https://doi.org/10.1186/s12872-017-0711-2">doi:10.1186/s12872-017-0711-2</a> <a target="_blank" rel="external noopener" href="https://www.ncbi.nlm.nih.gov/pubmed/29141592">pmid:29141592</a> <a target="_blank" rel="external noopener" href="https://pubmed.ncbi.nlm.nih.gov/PMC5688722/">pmcid:PMC5688722</a> <a target="_blank" rel="external noopener" href="https://fatcat.wiki/release/aa5dar4crje23mpvt4vdl2x7qa">fatcat:aa5dar4crje23mpvt4vdl2x7qa</a> </span>
<a target="_blank" rel="noopener" href="https://web.archive.org/web/20180721055224/https://bmccardiovascdisord.biomedcentral.com/track/pdf/10.1186/s12872-017-0711-2?site=bmccardiovascdisord.biomedcentral.com" title="fulltext PDF download" data-goatcounter-click="serp-fulltext" data-goatcounter-title="serp-fulltext"> <button class="ui simple right pointing dropdown compact black labeled icon button serp-button"> <i class="icon ia-icon"></i> Web Archive [PDF] <div class="menu fulltext-thumbnail"> <img src="https://blobs.fatcat.wiki/thumbnail/pdf/1f/8c/1f8c7b4b755115b659766d68285d7d1f15c7c658.180px.jpg" alt="fulltext thumbnail" loading="lazy"> </div> </button> </a> <a target="_blank" rel="external noopener noreferrer" href="https://doi.org/10.1186/s12872-017-0711-2"> <button class="ui left aligned compact blue labeled icon button serp-button"> <i class="unlock alternate icon" style="background-color: #fb971f;"></i> springer.com </button> </a> <a target="_blank" rel="external noopener" href="https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5688722" title="pubmed link"> <button class="ui compact blue labeled icon button serp-button"> <i class="file alternate outline icon"></i> pubmed.gov </button> </a>

The beta-isoform of the BRCA2 and CDKN1A(p21)-interacting protein (BCCIP) stabilizes nuclear RPL23/uL14

Emanuel Wyler, Franziska Wandrey, Lukas Badertscher, Christian Montellese, Daniel Alper, Ulrike Kutay
<span title="2014-08-19">2014</span> <i title="Wiley"> <a target="_blank" rel="noopener" href="https://fatcat.wiki/container/kn6dhptylrb77b5atyiom5ysjm" style="color: black;">FEBS Letters</a> </i> &nbsp;
Edited by Felix Wieland Keywords: BCCIP Ribosome biogenesis Eukaryotic initiation factor 6 (eIF6) Ribosomal protein RPL23/uL14 a b s t r a c t BRCA2 and CDKN1A(p21,CIP1)-interacting protein (BCCIP) is an evolutionary conserved protein implicated in maintenance of genome stability and cell cycle progression. Two isoforms of BCCIP with distinct C-terminal domains exist in humans. We show that mammalian BCCIPb, but not BCCIPa, forms a ternary complex with the ribosomal protein RPL23/uL14 and the
more &raquo; ... e-60S transacting factor eIF6. Complex formation is dependent on an intact C-terminal domain of BCCIPb. Depletion of BCCIPb reduces the pool of free RPL23, and decreases eIF6 levels in nucleoli. Overexpression of BCCIPb leads to nucleoplasmic accumulation of extra-ribosomal RPL23 and stabilizes overexpressed RPL23, suggesting that BCCIPb functions as nuclear chaperone for RPL23.
<span class="external-identifiers"> <a target="_blank" rel="external noopener noreferrer" href="https://doi.org/10.1016/j.febslet.2014.08.013">doi:10.1016/j.febslet.2014.08.013</a> <a target="_blank" rel="external noopener" href="https://www.ncbi.nlm.nih.gov/pubmed/25150171">pmid:25150171</a> <a target="_blank" rel="external noopener" href="https://fatcat.wiki/release/m74galhwxzfldgww62qcltnhoa">fatcat:m74galhwxzfldgww62qcltnhoa</a> </span>
<a target="_blank" rel="noopener" href="https://web.archive.org/web/20170927133432/http://publisher-connector.core.ac.uk/resourcesync/data/elsevier/pdf/53a/aHR0cDovL2FwaS5lbHNldmllci5jb20vY29udGVudC9hcnRpY2xlL3BpaS9zMDAxNDU3OTMxNDAwNjE0MA%3D%3D.pdf" title="fulltext PDF download" data-goatcounter-click="serp-fulltext" data-goatcounter-title="serp-fulltext"> <button class="ui simple right pointing dropdown compact black labeled icon button serp-button"> <i class="icon ia-icon"></i> Web Archive [PDF] <div class="menu fulltext-thumbnail"> <img src="https://blobs.fatcat.wiki/thumbnail/pdf/bc/7c/bc7c696e678a1709eee67b1e9db1010b9f315374.180px.jpg" alt="fulltext thumbnail" loading="lazy"> </div> </button> </a> <a target="_blank" rel="external noopener noreferrer" href="https://doi.org/10.1016/j.febslet.2014.08.013"> <button class="ui left aligned compact blue labeled icon button serp-button"> <i class="external alternate icon"></i> Publisher / doi.org </button> </a>

Clinical Use of High-Sensitivity Cardiac Troponin in Patients With Suspected Myocardial Infarction

Raphael Twerenbold, Jasper Boeddinghaus, Thomas Nestelberger, Karin Wildi, Maria Rubini Gimenez, Patrick Badertscher, Christian Mueller
<span title="">2017</span> <i title="Elsevier BV"> <a target="_blank" rel="noopener" href="https://fatcat.wiki/container/ssdz5shjvrai3ijjkutdhctqam" style="color: black;">Journal of the American College of Cardiology</a> </i> &nbsp;
High-sensitivity cardiac troponin (hs-cTn) assays have been used clinically by thousands of physicians in many countries throughout the world since their clinical introduction 7 years ago. In the early diagnosis of myocardial infarction (MI), beyond doubt, the most important indication of hs-cTn assays, these simple, inexpensive, and highly reproducible tools complement detailed clinical assessment including chest pain characteristics and the electrocardiogram. Hs-cTn assays for the first time
more &raquo; ... llowed the precise quantification of cardiomyocyte injury around the 99th percentile and thereby substantially increased the accuracy of MI detection from blood obtained at presentation to the emergency department (ED). Higher accuracy at ED presentation enabled the development and extensive validation of early hs-cTn-based diagnostic algorithms, which substantially reduced the time required for the safe rule-out or rule-in of MI. This review summarizes key principles underlying the safe and effective use of hs-cTn in the ED in patients with suspected MI. (J Am Coll Cardiol 2017;70:996-1012)
<span class="external-identifiers"> <a target="_blank" rel="external noopener noreferrer" href="https://doi.org/10.1016/j.jacc.2017.07.718">doi:10.1016/j.jacc.2017.07.718</a> <a target="_blank" rel="external noopener" href="https://www.ncbi.nlm.nih.gov/pubmed/28818210">pmid:28818210</a> <a target="_blank" rel="external noopener" href="https://fatcat.wiki/release/xvavo23g2zahjaxmrkqtdkmj74">fatcat:xvavo23g2zahjaxmrkqtdkmj74</a> </span>
<a target="_blank" rel="noopener" href="https://web.archive.org/web/20190214062650/http://www.onlinejacc.org:80/content/accj/70/8/996.full.pdf" title="fulltext PDF download" data-goatcounter-click="serp-fulltext" data-goatcounter-title="serp-fulltext"> <button class="ui simple right pointing dropdown compact black labeled icon button serp-button"> <i class="icon ia-icon"></i> Web Archive [PDF] <div class="menu fulltext-thumbnail"> <img src="https://blobs.fatcat.wiki/thumbnail/pdf/de/0c/de0c4fc7f65fccbcb36eb71197f01412fb668b48.180px.jpg" alt="fulltext thumbnail" loading="lazy"> </div> </button> </a> <a target="_blank" rel="external noopener noreferrer" href="https://doi.org/10.1016/j.jacc.2017.07.718"> <button class="ui left aligned compact blue labeled icon button serp-button"> <i class="external alternate icon"></i> elsevier.com </button> </a>
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